US3568008A - Electromagnetic switching device utilizing stray magnetic flux - Google Patents

Electromagnetic switching device utilizing stray magnetic flux Download PDF

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Publication number
US3568008A
US3568008A US819281A US3568008DA US3568008A US 3568008 A US3568008 A US 3568008A US 819281 A US819281 A US 819281A US 3568008D A US3568008D A US 3568008DA US 3568008 A US3568008 A US 3568008A
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United States
Prior art keywords
magnetic flux
winding
electromagnetic device
armature
switching means
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US819281A
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English (en)
Inventor
Shigeru Tanimura
Kenzo Kamei
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Omron Corp
Original Assignee
Omron Tateisi Electronics Co
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Omron Tateisi Electronics Co filed Critical Omron Tateisi Electronics Co
Application granted granted Critical
Publication of US3568008A publication Critical patent/US3568008A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H47/00—Circuit arrangements not adapted to a particular application of the relay and designed to obtain desired operating characteristics or to provide energising current
    • H01H47/02—Circuit arrangements not adapted to a particular application of the relay and designed to obtain desired operating characteristics or to provide energising current for modifying the operation of the relay
    • 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
    • H01F7/14—Pivoting armatures
    • 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
    • H01F7/1607—Armatures entering the winding
    • 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
    • H01F7/18—Circuit arrangements for obtaining desired operating characteristics, e.g. for slow operation, for sequential energisation of windings, for high-speed energisation of windings
    • H01F7/1805—Circuit arrangements for holding the operation of electromagnets or for holding the armature in attracted position with reduced energising current
    • H01F7/1833—Circuit arrangements for holding the operation of electromagnets or for holding the armature in attracted position with reduced energising current by changing number of parallel-connected turns or windings
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H43/00—Time or time-programme switches providing a choice of time-intervals for executing one or more switching actions and automatically terminating their operations after the programme is completed
    • H01H43/02—Details
    • H01H43/04—Means for time setting
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H50/00—Details of electromagnetic relays
    • H01H50/54—Contact arrangements
    • H01H50/541—Auxiliary contact devices
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H51/00—Electromagnetic relays
    • H01H51/28—Relays having both armature and contacts within a sealed casing outside which the operating coil is located, e.g. contact carried by a magnetic leaf spring or reed

Definitions

  • the electromagnetic device of the present invention comprises at least one winding for generating magnetic flux, one stator core magnetically coupled with the said winding, and a movable armature which is attracted to the core when the magnetic flux is generated; and is characterized in that at least one magnetically responsive switching means for controlling the said magnetic flux upon receiving stray magnetic flux is provided in a position where the said switching means receives the stray magnetic flux developed by existence of a gap or gaps between the armature and the stator core.
  • the electromagnetic device of the present invention can be made considerably smaller in size as well as requiring a smaller driving current than conventional devices, and has higher reliability. A delayed set operation is easily obtainable in the electromagnetic device of this invention.
  • This invention relates to an electromagnetic device for driving electric switches or various mechanical means such as a ratchet or a valve. More particularly, this invention relates to an electromagnetic device which takes larger current when driving its armature from its rest position to its set position and takes smaller current when keeping the armature in its set position.
  • an electromagnetic device requires a large number of ampere turns when driving its armature from rest position to a set positionand requires a smaller number of ampere turns to keep the armature in the set position. where the armature touches a core. Accordingly, conventional electromagnetic devices are so constituted that their ampere turns can be reduced to a'small value after the armature reaches the set position.'Such conventional devices require a pair of additional switch contacts which switch the circuit so that a current-restricting resistor is connected in series to the winding just after the setting of the device, or so that an auxiliary winding providedfor adding the necessary additional ampere turns to achieve the setting of the switch is disconnected after the setting of the device.
  • One object of the present invention is to provide an improved electromagnetic device excluding the above-mentioned shortcomings of conventional devices.
  • a further object of this invention is to provide an improved electromagnetic device capable of a delayed set operation.
  • the electromagnetic device of the present invention comprises at least one winding for generating magnetic flux, a stator core magnetically coupled with the said winding, and a movable armature which is attracted to the core when the magnetic flux is generated; and is characterizedin that at least a magnetically responsive switching means, for controlling the said magnetic flux upon receiving stray magnetic flux, is provided in a position where the said switching means receives the stray magnetic flux developed by existence of a gap or gaps between the armature and the stator core.
  • the said winding and the stator core form an electromagnet to attract the said movable armature to the core when the magnetic flux is generated by an exciting current in the winding.
  • Switch contacts of the circuit, or a mechanical means, such as a ratchet to be driven thereby can be linked to the said movable armature.
  • a reed switch, or a magnetically responsive semiconductor device can be employed as the said magnetically responsive switching means.
  • FIG. 1 is a top plan view of a relay constructed in accordance with one embodiment of the present invention
  • FIG. 2 is a side elevation view of the relay shown in FIG. 1;
  • FIG. 3 is a circuit diagram of an electromagnetic device embodying the present invention.
  • FIG. 4 is another circuit diagram of an electromagnetic device embodying the present invention.
  • FIG. 5 is a side sectional view of another relay constructed in accordance with another embodiment .of the present invention.
  • 1 FIG. 6 is a side sectional view of still another relay constructed in accordance with another embodiment of the present invention.
  • the electromagnet device shown in FIG. 1 and FIG. 2 relatesto a hinge-type relay.
  • an armature 1 made of iron is provided movably at a switch in this description denotes a magnetically responsive switching means comprising at least one pair of reed contacts of magnetic metal, of which at least one is resilient so as to enable it to be attracted by and contact and other reed contact when the magnetic flux surrounds them, and an airtight enclosure for enclosing the reed contacts.
  • the said magnetically responsive semiconductor device is a semiconductor device which performs a switching action in response to a change in the surrounding magnetic flux.
  • the magnetically responsive switching means responds to a decrease of the stray magnetic flux caused by touching of the armature to the core, and switches the electric circuit of the said winding to reduce the ampere turns of the winding to a low value just sufficient to hold the already attracted armature in its set position.
  • the supporter plate 3 is fixed upon the outer surface of a standing leg 4 of a yoke 5 made of iron, a cylindrical core 6 made of iron is fixed on the yoke 5, and a coil 7 is wound on a spool 8 enclosing the core 6.
  • a terminal board 9 bearing terminals 10 is fixed to another standing leg 11 of the yoke 5.
  • Arms 12 of thin elastic metal plate comprising contacts 13 and 13 on their moving ends, are fixed in aninsulated state upon the armature l.
  • a tension spring 14 is provided between a hook part 15 of the supporter plate 3 and a hook part 16 of the armature 1 in order to impart to the armature l a force to separate the armature from the core 6 by pivoting it about the supporting portion 2.
  • Fixed contacts 17 and 17 positioned to contact the contacts 13 and 13', respectively, are provided on the terminal board 9. Near a gap 19, which is formed between the armature 1 and the core 6 when they 'are apart, is provided a reed switch 18 for controlling the ampere turns of the coil.
  • the reed switch 18 can be located in any place where it will receive the stray magnetic flux which is formed during the period after the current has been fed to the coil 7 and before the armature l is attracted to the core 6.
  • the electrical configuration of the said relay can be provided in either way as shown in FIG. 3 or FIG. 4.
  • a first winding 71 and second winding 72 constitute the coil 7 referred to in FIG. 1 and FIG. 2.
  • the first winding 71 is connected directly across terminals 20 and 21 which lead to a DC power source 22 through a switch 23.
  • the second winding 72 and the reed switch 18 are connected in series between the terminals 20 and 21.
  • the armature 1 is not yet attracted to the core 6, on account of the insufficiency of the magnetic flux, while the reed switch 18 operates and closes the circuit of the second winding 72, in response to the straymagnetic flux existing around the gap 19 between the armature l and the core 6, thereby closing a current path through the second winding 72.
  • the current in the second winding 72 together with the current in the first winding 71, generates a large magnetic flux, and consequently, the armature 1 is attracted to the core 6.
  • the reed switch 18 is opened, thus extinguishing the current through the second winding 72 and thereby reducing the magnetic flux to a low level just sufficient for keeping the armature l in'touch with the core 6.
  • the total current fed tothedevice is considerably decreased; thereby lowering the power consumption of the device.
  • FIG. 4 is a circuit diagramiexhibitin'g another example of a circuit connection applicable to the relay illustrated in FIG. 1
  • a .winding 73 constitutesthe coil 7 shown in FIG. 1 and FIG. 2.
  • the winding 73 and a currentrestricting resistor 24 areconnected in series between terminals and 2lwhich lead to-a DC power source 22 through a switch 23.
  • the reed switch 18 is connected in parallel with the resistor 24.
  • the relay having a construction as described referring to FIG. 1 and FIG/2 as well as a connection as described referring to FIG. 4 operates as follows:
  • the armature l is not yet attracted to the core 6, on account of the insufficiency tion of the resistor 24 in series to the winding 73 and reducing the magnetic flux to a low level just sufficient to keep the armature l in contact with the core'6.
  • the electromagnetic device shown in connection with FIG. 5 relates to an example of a plunger-type relay.
  • an E- shaped stator core 31 is fixed on the bottom of a box-type housing 32.
  • a coil 33 is wound on the spool 34 fixed around the center leg 35 of the core 31.
  • An E-shaped movable armature 36 is provided to face opposite the core 31, being supported by pressure springs 37 so as to impart to the armature 36 a force to separate it from the core 31.
  • a reed switch 48 is provided in a hollow 38 of the spool 34, located near the gap 49 between the core'31 and the armature 36.
  • the contact carrier 39 is-connected with the armature 36 by a connecting pin 40.
  • a transverse contact plate 41 bearing contacts 43 issupported in a hole 42 of the contact carrier 39, being biased by a pressure spring 44.
  • fixed contacts 47 are provided opposite the said contacts 43; t I
  • the electromagnetic device shown in connection with FIG. 6 relates to another example of a plunger-type relay.
  • a reed switch 51 is provided in a hollow 52 located in a sidewall of the housing and near the gap 49 which is formed between the core 31 and the armature 36.
  • the remaining part is constructed in the same manner as described with reference to FIG. 5.
  • the electrical constitution of this relay can be made in either way as shown in FIG. 3 or FIG. 4.
  • the reed switches of the above-mentioned examples may be delayed-setting-type reed switches tilled with viscous fluid.
  • the reed switch closes after a lapse of a specific delay period, and therefore, the setting of the device is delayed.
  • a delay time within several seconds in the setting operation is easily obtainable.
  • the electromagnetic device of the present invention can be constructed to have a smaller coil as compared with-conventional devices because contacts hitherto provided on the armature for controlling the current after setting of the device is replaced by a magnetic sensitive switching means, and therefore, the necessary force to attract the armature to the core can be reduced by the extent hitherto required to press the contacts to touch each other.
  • adjustment of the operation of the device can be easily accomplished by adjusting the location and slant of the reed switch.
  • the electromagnetic device of the present invention has a great reliability on account of the use of a reliable reed switch.
  • a relay embodying the present invention all of the contacts provided on its armature can be employed for a switching circuit which is independent from the circuit of this relay, because the circuit of this relay is not connected to any of the contacts provided on the armature. That is to say, the relay embodying the present invention can be made smaller than the conventional one possessing the same number of contacts. Thus, the relay embodying the present invention can be made to possess more contacts in comparison with a conventional relay having a similar size.
  • a delayed setting operation is obtainable by employing a delayed-setting-type reed switch in an electromagnetic device of the present invention.
  • An electromagnetic device comprising at least one winding for generating a magnetic flux in response to a current applied through a circuit from an energizing source thereto, a
  • movable armature which is attracted to the core when a maximum level of magnetic flux is generated and held in contact with said core when a minimum level of magnetic flux is generated, at least one magnetically responsive means connected with the circuit supplying current from said source to said winding and responsive to said magnetic flux for switchably controlling the current applied to said winding to adjust said magnetic flux from a minimum level to a maximum level, said switching means being positioned to receive the stray magnetic flux developed by existence of a gap between the armature and the stator core.
  • said magnetically responsive switching means is in series with said winding and comprises at least one pair of reed con-' tacts of magnetic metal, of which at least one is resilient so as to enable it to be attracted by and contact the other reed contact when a magnetic flux surrounds them, and an airtight enclosure for enclosing the reed contacts.
  • the stator core and the armature form a plunger-type electromagnetic device
  • the said magnetically responsive switching means is placed in a hollow formed in a wall of a housing which encloses the said core, said armature and said winding, said switching means being connected in series with said winding and comprising at least one pair of reed contacts of magnetic metal of which at least one is resilient so as to enable it to be attracted by and contact the other reed contact when a magnetic flux'surrounds them, and an airtight enclosure for enclosing the reed contacts.

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  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Electromagnets (AREA)
US819281A 1968-04-25 1969-04-25 Electromagnetic switching device utilizing stray magnetic flux Expired - Lifetime US3568008A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2809668 1968-04-25

Publications (1)

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US3568008A true US3568008A (en) 1971-03-02

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Application Number Title Priority Date Filing Date
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US (1) US3568008A (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html)
DE (1) DE1921232A1 (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html)
FR (1) FR2006888A1 (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html)
GB (1) GB1213924A (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html)

Cited By (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3916264A (en) * 1974-07-01 1975-10-28 Texas Instruments Inc Time delay apparatus
US3979705A (en) * 1974-05-13 1976-09-07 Trw Inc. Automotive relay of the hold-in type
US4004258A (en) * 1974-11-20 1977-01-18 Valcor Engineering Corporation Position indicating pulse latching solenoid
US4038626A (en) * 1975-06-11 1977-07-26 I-T-E Imperial Corporation High voltage contactor
US4242004A (en) * 1979-03-21 1980-12-30 Extel Corporation Dot matrix printhead driver
GB2156156A (en) * 1984-03-15 1985-10-02 Hager Electro Gmbh & Co Electromagnetic switch arrangement
US4603370A (en) * 1984-10-03 1986-07-29 General Research Of Electronics, Inc. Power-saving relay circuit
US5113308A (en) * 1990-01-08 1992-05-12 Uchiya Thermostat Co. Actuator with a built-in reed switch
US5363270A (en) * 1992-09-18 1994-11-08 General Motors Corporation Rapid response dual coil electromagnetic actuator with capacitor
US5377068A (en) * 1992-10-19 1994-12-27 Predator Systems Inc. Electromagnet with holding control
US5450276A (en) * 1993-03-17 1995-09-12 Telemecanique Electromagnetic switch device
US20020163409A1 (en) * 2001-05-04 2002-11-07 Alcatel Telecommunication relay array for DSL network configuration
US20030011453A1 (en) * 2000-12-22 2003-01-16 Volker Nadenau Electromagnet
CN102693876A (zh) * 2011-03-24 2012-09-26 崔万恒 一种直流高压继电器
US8896402B2 (en) * 2011-08-31 2014-11-25 Siemens Aktiengesellschaft Apparatus for supporting a hinged armature
US20140361858A1 (en) * 2013-06-05 2014-12-11 Hitachi, Ltd. Actuator for contactor
DE102016101501A1 (de) * 2016-01-28 2017-08-03 Phoenix Contact Gmbh & Co. Kg Elektromechanisches Relais und Vorrichtung zum Erkennen des Schaltzustandes eines elektromechanischen Relais
AT518231A3 (de) * 2016-01-28 2020-05-15 Phoenix Contact Gmbh & Co Gepoltes elektromechanisches Relais mit steuerbarer Leistungsaufnahme
CN114695020A (zh) * 2022-04-06 2022-07-01 浙江英洛华新能源科技有限公司 用于检测主触点工作状态的继电器及主触点工作状态判断方法

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
IT209349Z2 (it) * 1985-10-15 1988-10-05 Elettrocondutture Struttura di attuatore elettromagnetico polarizzato.
FR2677806B1 (fr) * 1991-06-17 1994-05-06 Telemecanique Dispositif interrupteur auxiliaire pour appareil interrupteur principal.
DE59501605D1 (de) 1995-02-09 1998-04-16 Rockwell Automation Ag Einrichtung zur Steuerung eines Elektromagneten
WO2001013397A1 (de) * 1999-08-12 2001-02-22 Siemens Aktiengesellschaft Elektromagnetisches schaltgerät

Cited By (24)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3979705A (en) * 1974-05-13 1976-09-07 Trw Inc. Automotive relay of the hold-in type
US3916264A (en) * 1974-07-01 1975-10-28 Texas Instruments Inc Time delay apparatus
US4004258A (en) * 1974-11-20 1977-01-18 Valcor Engineering Corporation Position indicating pulse latching solenoid
US4038626A (en) * 1975-06-11 1977-07-26 I-T-E Imperial Corporation High voltage contactor
US4242004A (en) * 1979-03-21 1980-12-30 Extel Corporation Dot matrix printhead driver
GB2156156A (en) * 1984-03-15 1985-10-02 Hager Electro Gmbh & Co Electromagnetic switch arrangement
US4603370A (en) * 1984-10-03 1986-07-29 General Research Of Electronics, Inc. Power-saving relay circuit
US5113308A (en) * 1990-01-08 1992-05-12 Uchiya Thermostat Co. Actuator with a built-in reed switch
AU637634B2 (en) * 1990-01-08 1993-06-03 Uchiya Thermostat Co., Ltd Actuator with a built-in reed switch
US5363270A (en) * 1992-09-18 1994-11-08 General Motors Corporation Rapid response dual coil electromagnetic actuator with capacitor
US5377068A (en) * 1992-10-19 1994-12-27 Predator Systems Inc. Electromagnet with holding control
US5450276A (en) * 1993-03-17 1995-09-12 Telemecanique Electromagnetic switch device
US6724287B2 (en) * 2000-12-22 2004-04-20 Robert Bosch Gmbh Electromagnet
US20030011453A1 (en) * 2000-12-22 2003-01-16 Volker Nadenau Electromagnet
US20020163409A1 (en) * 2001-05-04 2002-11-07 Alcatel Telecommunication relay array for DSL network configuration
CN102693876A (zh) * 2011-03-24 2012-09-26 崔万恒 一种直流高压继电器
US8896402B2 (en) * 2011-08-31 2014-11-25 Siemens Aktiengesellschaft Apparatus for supporting a hinged armature
US20140361858A1 (en) * 2013-06-05 2014-12-11 Hitachi, Ltd. Actuator for contactor
US9142371B2 (en) * 2013-06-05 2015-09-22 Hitachi, Ltd. Actuator for contactor
DE102016101501A1 (de) * 2016-01-28 2017-08-03 Phoenix Contact Gmbh & Co. Kg Elektromechanisches Relais und Vorrichtung zum Erkennen des Schaltzustandes eines elektromechanischen Relais
DE102016101501B4 (de) 2016-01-28 2018-12-27 Phoenix Contact Gmbh & Co. Kg Elektromechanisches Relais und Vorrichtung zum Erkennen des Schaltzustandes eines elektromechanischen Relais
AT518231A3 (de) * 2016-01-28 2020-05-15 Phoenix Contact Gmbh & Co Gepoltes elektromechanisches Relais mit steuerbarer Leistungsaufnahme
AT518231B1 (de) * 2016-01-28 2020-07-15 Phoenix Contact Gmbh & Co Gepoltes elektromechanisches Relais mit steuerbarer Leistungsaufnahme
CN114695020A (zh) * 2022-04-06 2022-07-01 浙江英洛华新能源科技有限公司 用于检测主触点工作状态的继电器及主触点工作状态判断方法

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Publication number Publication date
GB1213924A (en) 1970-11-25
DE1921232A1 (de) 1969-11-20
FR2006888A1 (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html) 1970-01-02

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