US3234436A - Rotary electromagnetic actuator - Google Patents

Rotary electromagnetic actuator Download PDF

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Publication number
US3234436A
US3234436A US223164A US22316462A US3234436A US 3234436 A US3234436 A US 3234436A US 223164 A US223164 A US 223164A US 22316462 A US22316462 A US 22316462A US 3234436 A US3234436 A US 3234436A
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Prior art keywords
rotor
pole pieces
shaft
coil
stator
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US223164A
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Jacob J Bieger
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Daco Instrument Co Inc
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Daco Instrument Co Inc
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    • HELECTRICITY
    • H01BASIC ELECTRIC ELEMENTS
    • H01FMAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F7/00Magnets
    • H01F7/06Electromagnets; Actuators including electromagnets
    • H01F7/08Electromagnets; Actuators including electromagnets with armatures
    • H01F7/14Pivoting armatures
    • H01F7/145Rotary electromagnets with variable gap

Description

Feb. 8, 1966 J. J. BIEGER ROTARY ELECTROMAGNETIC ACTUATOR Mm QNQQN Q Q Q g Filed Sept. 12, 1962 Feb. 8, 1966 J. J. BIEGER 3,234,436
ROTARY ELECTROMAGNETIC ACTUATOR Filed Sept. 12, 1962 2 Sheets-Sheet Z INVENTOR. Jacoa ul' 3/5657? aymWw ATTORNEYS United States Patent- 3,23%;436 RQTARY ELECTROMAGNETIC ACTUATOR"- JaeobfL Bi'eger," Queen'srVillhggwNzYa; assignorpby; mesne assignmentst-r tow-"Dacoi Instrument Company; Inca, Brooklyn NzYt-qpa corporationmf New York- Filedasept 12 1962,: Ser.. No, 223,164
7 Claims. (Cl'.f317---197) This invention relates to rotary electromagnetic actu atoi'sf More particularlyfi this invention relates to sole noids having rotatable armatiifes which may be angularly displaced "to one of three"distinctpositions.
The typvof solenoid? to: which the *pres'entinventio'n pertainshas particularutilityas an indicatingdevice' in electricalcircuits. It isoftennecessary to give-a visual indi'c'ation to "showwhich'of a plurality of circuits has been energized? As "a specific example; it might bedesirable" to'indicate whichod two' circuits *is in anenergized state 'orgwhe'ther neither hasbeenenergized; For purp'oses'of simplicity and economy, such a visual -indication maybe readily given by. placing the coils oi'a rotary elec tro'rnagnetic actuator, or. solnoidfin the separate circuits whereby a visual indicator may be -rotated' in one of -two directions depending on which circuit is energized. If the indicator remains in its initial position this would 'mean that neither circuithas "been energized; Accortiirigly,' it is-an objctbf'this -invention to provide an improved three-position rotary solenoids Another object is to-provide a rotary solenoid which i's rugged'in design, simple in construction and economical to manufacturer.
The'objects of'tthe invention areraccom-plished by providing two oppositely disposed stator sections,-a rotor shaft extending therethrough', t and a pain of rotors rotatably displaced fromone. another and associated with respective stators, the rotors beingaindividually. operable to rotate thev shaft in a given direction when the coil of its=associated-statoris energized. A return means, which may comprise a pair ofpermanent magnetsioperative in conjunction with thefouter pole pieces ofthe'stators, biases the rotor shaft-to its center position; so that whenneither coil is energized the shaft will maintain its initial 'position.
The mannerin which these objects are 1 accomplished will i b'e furthet explained -with reference to "the following specification and drawingsywher'ein t FIG-1- lis an exploded view ofrtheithree-position actu, ator accordingntoi the: invention;
FIGJ 2 is'ia side view in section of the rotary actuator;
FIG 4 is aview'alongztheline le4 of FIG. 2; t FIG. Sis 'a-crossr sectional view-tof another embodiment of thetinvention;
FIG; 6-is -a cut-iawayttopsview of the embodiment of FIG 4; and
FIG. 7 is an exploded view of the rotor and jstoprmember of the second embodiment.
In FIGS. .1-to:3,1the' three-positionrotary solenoid is shown comprising first-and second statortsections 10 and 12, respectively. Statorsection'10includes a base 14, a cylindricalwall'-15press--fit thereover; and an' outwardly extending center'pole piece 16*ii'1tegrally formedwith base 14 lnadd-itiong stator-section '10 in'clu'des two oppositely disposed, outer pole/piecetrnembers lhand 18 integrally formed with wall 15. Stator section 12.. is constructed identically as stator 10'and includes .a' base 20,?a center pole piece 21, and .two outer pole pieces 22 and23extendingfrom ta;cylindrical wallpor-tiont24. The stators are made of a material which will provide suitable flux pathswhen -the solenoid is energized; i As shown-in FIG. 2, the stators of the assembled solenoid are arranged in end-to-end relationship with base 14 abutting against base 3,234,436 Patented Feb. 8, 1966 20; and pole pieces' 17 and ls' of stator- 10*alignted with pole pieces 22 and 2'3, respectively; of stator 12? The stators may 'be 'held 'in this relationship by-ineans is Wound-around *a' second spool -lik'e coil form -34 hav ing a central-bore"35 "into whichcenter polepiece 21 extends.--
The center pole pie'ces are "slightly longer than their associated coil form'; so thatwheiithe "ends -of coi'l forms 30 and =32-rest against the tops spectively; the upper portions o protrude from the coil for msi A rotor shaft "38 extends through the center-' of c'oil forms 30- and 32 and is "suitablyjournaled in bearings 33 in center pole pieces 16 and- 21- of "statorsect-ions= 10 and 12, respectively. A first bow-shaped "rotor 40='includingan integrally formed hub me'mber' '42" is-secured to shaft 38 immediately above centerpole *piece' -16i Rotor 40 rnay -bemade of: solid magnetic material and includes a centerrecess 43 beneath hub 42'i into which the protruding end' of center-pole piece 16'extends. In a similar manner, a second -bow-shaped rotor 46' i'nclud ing an-- integralhub -member 47 f issecured 'to sha ft 38 opposite rotor 40. Rotor: 46 is also centrally recessed; so that the protruding end of center-pole piece 21iextends substantially into the :rotorr When! one of coils 28 and 32 is energized;=a magnetic flux is generated iinrits? associated stator wall andipole pieces. Th'e respectiver'rotorris attracted -by theimagneticlines of flux:"passingrtransversely through tthe air gap (betweenrthe' rotor'and 'outer' pole pieces) tothe rotorr. Theesalient'epoles of the "r'otortare attracted to the stator pole piecessoft opposite'ipolarity thus imparting a'rotary motiodtoithe rotor; By'utilizing recessedrotors and' mounting the mover respective center pole pieces of teach. stator, theetfectof :the magneticthrust which acts downwardly: on'vthetrotors, and thus-Lterids to lessen the torque developed during rotationfis minimized. As *shown in 'FIGS'. 3 and -4,' the'rotors are' rotatably -dis placedon shaft 38' with: respect to each'cothertso that energizationof coili28 x-will 'cause' "rotor 40 'to. rotate shaft 38 r'in'iazclockwise direction,'rwhi'le energization' iof coil-32 will cause rotor 46 rtot rotaterthe 'shaftt'in a counter-clock;
wise direction;
Rotor shaft 382 is: returned?! to its initial-* position by means :of a .pairofflat; annulartpermanent magnets. 48 and 50 which may be-'pressxfit ito hubmembers 42and 4-7", respectively; Magnets48 Sand 50 fliHVG magnetic :fields 'as illustrated :in FIGS.- 31 and-:+4; whichgexertiforcesrwith respect to their associated outer pole pieceswso that magnet' 48" tends s to rotatei shaft- 38 counterclockwise, while magnet SU-vtends to rotatev'theshaft in: a? clockwise direction-.1 Accordi'nglygxwhenathe solenoidis-deaenergized; the rotor. shaft maintains a position in :whichthe opposing magnetic forcesaret equal or 'balanced. I
The solenoidalso *includcswa; pair: ofrthin'a'nnular stop members 52 and- 54 press fitted': to' the" extremities of. hubs Y 42 and 1:47," respectively;v for limiting "the rotary movement'ofishaft38. Stopirme'mber SZ includes cars 55 and 56adapted to abut again'st-ou-terp'ole pieces -18 and 17, respectively; whenishaft38 is rotatedfclockwiser Stop member 54* includes ears 57" and r 58?" adapted to: abut against pole pieces 22 and 23,..respectivel-y; when-shaft 38 is-rotated in a counterclockwise;direction-.=
The/entire solenoid may becenclosed in a pair iof:cylin'- drical end caps 60 and 62. A small insulated tubex64 fits into aperture 65 of tube 60 to receive the leads of wise direction until the movement is arrested by abutment of the ears of stop member 52 against outer pole pieces 17 and 18. When the energization of coil 28 is removed, the unbalanced forces of the displaced magnets 48 and 50 return rotor shaft 38 to its original position at which point the :forces -of the two magnets are again balanced; Similarly, if current is passed through coil 32, rotor 46 rotates shaft 38 in a counterclockwise direction, and when the current is removed, the unbalanced magnetic fields of magnets 48 and 50 return the shaft to its initial position. An alternate embodiment of the invention, in which a return spring is employed, is illustrated in FIGS. -7. Only one stator section is illustrated, since the second section could be substantially identical, as discussed above with reference to FIGS. 1-4. In fact, since the individual stator sections would have utility by themselves in any situation wherein only two separate angular positions are necessary, this embodiment will be described as a single stator, two position, rotary solenoid.
The stator of the second embodiment includes a base 72 and a cylindrical wall 70 press fit thereover. A pair of integral, curved pole pieces 74 and 76 extend upwardly from wall 70 at opposite ends of a diameter. A center pole piece 78 is integrally formed with base 72 and includes a suitable bore for receiving a rotor shaft 82. A rotor 80 including hub member 81 (as shown in FIG. 7), is fixed to shaft 82 near the top thereof.
A spiral return spring 84 is wound around rotor-hub 81 immediately above rotor 80. One end of spring 84 is secured to hub member 81 while the other end is secured to pole piece. 76 through a slot 86 in the pole piece. Spring 84 exerts a force which tends to rotate rotor 80 in a clockwise direction.
A stop member, comprising a circular disc 88, is secured to the top of hub 81 immediately above spring 84. Disc 88includes a pair of oppositely disposed ears 89 and 90 adapted to abut against edges 92 and 93 of pole pieces 74 and 76. The stopmember and rotor are slightly offset from one another so that when coil 79 is energized and the rotor is rotated counterclockwise from the deene'rgized 3. A rotary electromagnetic actuator comprising, a first stator having a first coil and a first rotor associated therewith, a second stator having a second coil and a second rotor associated therewith, said firs-t and second stators each including a central pole piece and a pair of oppositely disposed pole pieces, each of said central pole pieces extending into and being perpendicular to its respective rotor, a rotor shaft passing through said stators, said first and second rotors'bcing secured to said shaft and disposed relative to their respective pole pieces whereby energization of said first coil causes said first rotor to rotate said shaft to a first position, and energization of said second coil causes said second rotor to rotate said position indicated in FIG. 6, the cars 89 and 90 abut against edges 93 ofipole pieces 74 and 76. When excitation is removed, spring 84 rotatesithe rotor clockwise to its initial position as determined by abutment of cars 89 and 90 against'edges92 of the outer pole'pieces.
Although specific embodiments of the invention have been disclosed, manymodifications thereof will be obvious to one skilled in .the art and the invention is not to be limited except as defined in the following claims.
I claim:
1. A rotary electromagnetic actuator comprising a first 'coil and first pole pieces associated therewith, a second coil and second pole pieces associated therewith, a rotor :shaft passing through said coils, first andsecond rotors secured to said shaft and operativelyassociated with said first pole pieces and said second pole pieces, respectively, :said rotors being disposed relative to their respective pole pieces whereby energization of said first coil causessaid first rotor to rotate said shaft to a first position and energization of saidsecond coil causes said second rotor to rotate said shaft to a second position, and a means biasing said shaft to a third position intermediate, said first and second positions.
2. A rotary electromagnetic actuator as recited inclaim -1 wherein said biasing means include. a permanent magnet.
shaft to a second position, stop means for limiting the rotation of said shaft in either direction, and means for returning said shaft to an initial position intermediate to said first and second positions when neither of said coils is energized. i i
4. A rotary electromagnetic actuator according to claim 3 wherein said return means includes magnetic discs secured to said rotor shaft and operatively associated with said first and second stators, the magnetic forces of said discs being directed so as to bias said rotor shaftto said initial position. I
5. A rotary electromagnetic actuator according to claim 4 wherein said first and second stators are identical and include a cylindrical base integrally formed with its respective pole pieces, said stators being arranged in endto-end fashion, one of said rotors being displaced in a counterclockwisedirection with respect to its pole pieces, and the other rotor being displaced in a clockwise direction with respect to its pole pieces.
6. A rotary electromagnetic actuator according to claim 5 wherein said stop means includes a membersecured to said shaft and adapted to abut against the pole pieces of one of said stators.
7. A rotary electromagnetic actuator comprising a cylindrical stator having three elongated pole pieces arranged in spaced locations, two of said pole pieces com prising opposing portions of the cylindrical surface of said stator, the other pole'piece extending axially from the center of said stator, a rotor shaft rotatably' mounted in said central pole piece,- extending. through the central pole piece of said stator, and beyond the opposing pole pieces, a rotor secured to said shaft adjacent the free end of said central pole piece, said central pole piece extending into and being perpendicular to said rotor, said rotor having outer faces arranged to rotate past the inside faces of said opposing pole pieces, electromagnetic means sure rounding'said central pole for energizing said pole pieces to rotate said rotor in one direction, spring return means to rotate the rotor in the opposite direction when said electromagnetic means is not effective and, stop'means for limiting the rotation of the rotor, said stop means including a segmented disc-like member secured to said rotor having means to abut against one of said opposed pole pieces.
References Cited by the Examiner UNITED STATES PATENTS i Y 2,869,048 1/1959 Reed; 317491 2,950,424 8/1960 Smith et al. 317 6 5-X 3,039,027 6/1962 Cuches 317 1 97 V FOREIGN PATENTS 830,225 2/1952 Germany. I
102,130 8/1962 Holland.
BERNARD GILHEANY, Primary Examiner. 7 JOHN F. BURNS, LARAMIE E. ASKIN, Examiners

Claims (1)

1. A ROTARY ELECTROMAGNETIC ACTUATOR COMPRISING A FIRST COIL AND FIRST POLE PIECES ASSOCIATED THEREWITH, A SECOND COIL AND SECOND POLE PIECES ASSOCIATED THEREWITH, A ROTOR SHAFT PASSING THROUGH SAID COILS, FIRST AND SECOND ROTORS SECURED TO SAID SHAFT AND OPERATIVELY ASSOCIATED WITH SAID FIRST POLE PIECES AND SAID SECOND POLE PIECES, RESPECTIVELY, SAID ROTORS BEING DISPOSED RELATIVE TO THEIR RESPECTIVE POLE PIECES WHEREBY ENERGIZATION OF SAID FIRST COIL CAUSES SAID
US223164A 1962-09-12 1962-09-12 Rotary electromagnetic actuator Expired - Lifetime US3234436A (en)

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US223164A US3234436A (en) 1962-09-12 1962-09-12 Rotary electromagnetic actuator
GB1511063A GB988819A (en) 1962-09-12 1963-04-17 Rotary electromagnetic actuators
DE19631464536 DE1464536A1 (en) 1962-09-12 1963-05-07 Rotary solenoid

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Cited By (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3430170A (en) * 1967-02-24 1969-02-25 Middlebury Mfg Co Inc Magnetic flag
US3435392A (en) * 1967-03-24 1969-03-25 Cons Electronics Ind Alternating current rotary solenoid having a rotor with permanent magnet poles
US4083024A (en) * 1976-10-07 1978-04-04 Datron Systems, Inc. Miniature relay
US4510403A (en) * 1984-02-13 1985-04-09 Pneumo Corporation Limited angle torque motor with magnetic centering and stops
US4525696A (en) * 1980-11-28 1985-06-25 Minnesota Mining & Manufacturing Company Driver for rotating a magnetic playback head
US4596970A (en) * 1984-12-21 1986-06-24 Pneumo Corporation Limited angle torque motor with high stiffness and natural frequency
US4600910A (en) * 1984-12-21 1986-07-15 Pneumo Corporation Limited angle torque motor with high torque output multiple coils and increased magnetic centering torque
US4612526A (en) * 1984-12-21 1986-09-16 Pneumo Corporation Torque motor with high torque poles and magnetic centering spring adjustment
WO1991003062A1 (en) * 1989-08-16 1991-03-07 Robert Bosch Gmbh Electromagnetic rotating actuator
WO1991003063A1 (en) * 1989-08-16 1991-03-07 Robert Bosch Gmbh Electromagnetic rotating actuator
US20050189825A1 (en) * 2004-01-29 2005-09-01 Philipp Brodt Bistable rotary solenoid
US20060220490A1 (en) * 2005-03-31 2006-10-05 Nobuaki Watanabe Electromagnetic actuator and camera blade driving device
US7794024B1 (en) 2009-03-31 2010-09-14 Tk Holdings Inc. Seat belt buckle
US20120261499A1 (en) * 2009-11-10 2012-10-18 Andrew Dames Solenoid actuator
US9991773B2 (en) 2015-02-06 2018-06-05 William R. Benner, Jr. Low cost limited rotation rotary actuator
US10720824B2 (en) 2015-02-06 2020-07-21 William R. Benner, Jr. Low cost limited rotation rotary actuator

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2573859Y2 (en) * 1991-11-21 1998-06-04 株式会社ハーモニック・ドライブ・システムズ Home position return mechanism for electromagnetic finite rotary motor

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
NL102130C (en) * 1956-03-09
DE830225C (en) * 1948-10-25 1952-02-04 Siemens Ag Noiseless, non-scattering relay
US2869048A (en) * 1952-05-22 1959-01-13 Ultra Electric Inc Electromagnetic device
US2950424A (en) * 1957-07-03 1960-08-23 Genevieve I Magnuson Solenoid and rotatable shaft device
US3039027A (en) * 1959-02-19 1962-06-12 Daco Instr Company Rotary actuator

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE830225C (en) * 1948-10-25 1952-02-04 Siemens Ag Noiseless, non-scattering relay
US2869048A (en) * 1952-05-22 1959-01-13 Ultra Electric Inc Electromagnetic device
NL102130C (en) * 1956-03-09
US2950424A (en) * 1957-07-03 1960-08-23 Genevieve I Magnuson Solenoid and rotatable shaft device
US3039027A (en) * 1959-02-19 1962-06-12 Daco Instr Company Rotary actuator

Cited By (27)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3430170A (en) * 1967-02-24 1969-02-25 Middlebury Mfg Co Inc Magnetic flag
US3435392A (en) * 1967-03-24 1969-03-25 Cons Electronics Ind Alternating current rotary solenoid having a rotor with permanent magnet poles
US4083024A (en) * 1976-10-07 1978-04-04 Datron Systems, Inc. Miniature relay
US4525696A (en) * 1980-11-28 1985-06-25 Minnesota Mining & Manufacturing Company Driver for rotating a magnetic playback head
US4510403A (en) * 1984-02-13 1985-04-09 Pneumo Corporation Limited angle torque motor with magnetic centering and stops
US4600910A (en) * 1984-12-21 1986-07-15 Pneumo Corporation Limited angle torque motor with high torque output multiple coils and increased magnetic centering torque
EP0186501A2 (en) * 1984-12-21 1986-07-02 Pneumo Abex Corporation Limited angle torque motor with high stiffness and natural frequency
US4596970A (en) * 1984-12-21 1986-06-24 Pneumo Corporation Limited angle torque motor with high stiffness and natural frequency
US4612526A (en) * 1984-12-21 1986-09-16 Pneumo Corporation Torque motor with high torque poles and magnetic centering spring adjustment
EP0186501A3 (en) * 1984-12-21 1987-01-14 Pneumo Corporation Limited angle torque motor with high stiffness and natural frequency
WO1991003062A1 (en) * 1989-08-16 1991-03-07 Robert Bosch Gmbh Electromagnetic rotating actuator
WO1991003063A1 (en) * 1989-08-16 1991-03-07 Robert Bosch Gmbh Electromagnetic rotating actuator
AU638266B2 (en) * 1989-08-16 1993-06-24 Robert Bosch Gmbh Electromagnetic rotating actuator
US5402022A (en) * 1989-08-16 1995-03-28 Robert Bosch Gmbh Electromagnetic rotary actuator
AU648461B2 (en) * 1989-08-16 1994-04-21 Robert Bosch Gmbh Electromagnetic rotating actuator
US20050189825A1 (en) * 2004-01-29 2005-09-01 Philipp Brodt Bistable rotary solenoid
US20060220490A1 (en) * 2005-03-31 2006-10-05 Nobuaki Watanabe Electromagnetic actuator and camera blade driving device
US7649300B2 (en) * 2005-03-31 2010-01-19 Nidec Copal Corporation Electromagnetic actuator and camera blade driving device
US7794024B1 (en) 2009-03-31 2010-09-14 Tk Holdings Inc. Seat belt buckle
US20100244424A1 (en) * 2009-03-31 2010-09-30 Tk Holdings Inc. Seat belt buckle
US20100325845A1 (en) * 2009-03-31 2010-12-30 Tk Holdings Inc. Seat belt buckle
US7963614B2 (en) 2009-03-31 2011-06-21 Tk Holdings Inc. Seat belt buckle
US20120261499A1 (en) * 2009-11-10 2012-10-18 Andrew Dames Solenoid actuator
US9530551B2 (en) * 2009-11-10 2016-12-27 Sentec Ltd Solenoid actuator
US9991773B2 (en) 2015-02-06 2018-06-05 William R. Benner, Jr. Low cost limited rotation rotary actuator
US10305358B2 (en) 2015-02-06 2019-05-28 William R. Benner, Jr. Low cost limited rotation rotary actuator
US10720824B2 (en) 2015-02-06 2020-07-21 William R. Benner, Jr. Low cost limited rotation rotary actuator

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GB988819A (en) 1965-04-14
DE1464536A1 (en) 1969-04-10

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