High frequency electromechanical generator

Abstract

Claims

1. A HIGH FREQUENCY ELECTROMECHANICAL GENERATOR COMPRISING: A ROTOR MEMBER; AND AT LEAST ONE STATOR MEMBER POSITIONED TO DEFINE WITH SAID ROTOR MEMBER A PERMANENT MAGNETIC FLUX AIR GAP THEREBETWEEN, ONE OF SAID MEMBERS INCORPORATING AN INDUCTOR MULTIPOLAR STRUCTURE, SAID ROTOR MEMBER COMPRISING, ON THE AIRGAP FACE OF A MAGNETIC BASE PIECE, EVENLY DISTRIBUTED AND CONSTANT PITCH MAGNETIC TEETH AND SAID STATOR MEMBER COMPRISING, ON THE AIRGAP FACE OF A MAGNETIC BASE STRUCTURE, EVENLY DISTRIBUTED GROUPS OF CONSTANT PITCH MAGNETIC TEETH, SAID GROUPS BEING SPACED APRAT BY ONE PITCH PLUS A FRACTION OF SAID PITCH, AND AN EVENLY DEVELOPED WINDING AROUND SAID GROUPS OF TEETH.
1966 J. HENRY-BAUDOT HIGH FREQUENCY ELECTROMECHANICAL GENERATOR Filed April 15. 1960 ni----i FIG.4- United States Patent 3,230,406 HIGH FREQUENCY ELECTROMECHANICAL GENERATOR Jacques Henry-Baudot, Antony, France, assignor to Printed Motors Inc., New York, N.Y. Filed Apr. 15, 1960, Ser. No. 22,507 Claims priority, application France, May 12, 1959, 794,638, Patent 1,234,263 13 Claims. (Cl. 310-155) The present invention relates to improvements in high frequency electromechanical generators. An object of the invention is to devise a high frequency electromechanical generator operating on the principle of modulating a permanent magnetic multipolar field in a simple and eflicient structural arrangement of the rotor and stator members thereof. A further object of the invention is to so devise said high frequency electromechanical generator structure that it is readily adaptable to the so-called printed circuit techniques for making at least part of said generators. The invention is primarily concerned with axial airgap rotating machines though it may easily be adapted also to the design of radial airgap machines. Briefly summarized, a high frequency electromechanical generator according to the invention comprises a rotor member and at least one stator member for defining a magnetic airgap wherein a permanent magnetic flux is established as one of said members incorporates an inductor pole structure; the rotor member comprises 0n the airgap face of a magnetic base piece, evenly distributed constant pitch magnetic teeth. The stator member is provided on the airgap face of a magnetic base piece with first, evenly distributed groups of constant pitch magnetic teeth, said groups being spaced by intervals widened by a fraction of said pitch, and secondly with an evenly developed winding around said groups of teeth for collecting the high frequency current derived from the interaction of said permanent magnetic flux and said magnetic teeth arrangement. In an axial airgap machine, the rotor member is placed between two identically made and duly registering stator members so that the axial magnetic attractions are balanced out in the machine. When a true A.C. waveform is required for the collected high frequency current, the said fraction of pitch is made equal to one-half of said pitch in the intervals between the groups of stator teeth. The stator winding is preferably a printed circuit winding, i.e. of bare and flat conductors intimately adhering to an insulating structure and, preferably further, in such a case, the insulating surface is obtained by forming at least that part of the magnetic base piece facing the airgap of a magnetic and insulating material. These and further features will be more fully described with relation to the accompanying drawings, wherein: FIG. 1 shows a cross-section through a first illustrative embodiment of a machine according to the invention; FIG. 2 shows on a larger scale, part of a linear development of facing portions of the rotor and stator members of the machine; FIG. 3 shows a front view of one face of the rotor with the stator shown in dotted line and having the permanent magnet poles indicated thereon; FIG. 4 shows a front view of one face of the stator, facing the airgap; and FIG. 5 shows a cross-section through a modification of a machine according to FIG. 1. The difference between the embodiments of FIGS. 1 and 5 lies in the fact that, in FIG. 1, mechanically separated magnetic poles are included in the structural arrangement whereas in FIG. 5 said poles are considered as impressed by magnetic treatment into a highly coercive and remanent material. The examples concern axial airgap machines; consequently, the members are made discoidal. The transposition to radial airgap machines with cylindrical members is quite apparent. For the sake of clarity of the drawings, the number of magnetic teeth, either in the rotor or the stator member is shown reduced with respect to actual practice reaching machines capable of delivering electrical A.C. currents of such high frequencies as 10,000 Hz. and higher ones. For instance, a machine according to the invention, having six permanent magnetic poles and twelve modulating poles, each of which comprises a group of 11 teeth, and the rotor comprising teeth, the frequency is 15,000 Hz. at a rotation speed equal to 6,000 r.p.m. The shown examples concern a six pole machine, each pole spanning an are 0 equal to 60, and twelve modulating poles, each one spanning an are 1) equal to 30, FIG. 4. The angular pitch of the rotor teeth, FIG. 3 is made equal to a certain value 2a and the same pitch is provided for the stator teeth, as shown in FIG. 4, within any one of the groups of teeth in the stator member. The figures show the half-pitch a so that in FIG. 4 it is easily seen that, between the groups of teeth, the pitch is increased by a. Said relation is also obvious from the plane development of FIG. 2. In the axial airgap machines illustrated, two stator members are provided, one on each side of the rotor. Such an arrangement seeks to eliminate the stray magnetic attraction of the rotor by each one of the stator members. It will be of no interest in coaxial arrangement of members. The rotor member 1 is made of a ring of a magnetic material, which is preferably also an insulating material such as certain ferrites, provided on both faces with evenly distributed radial and sectorial teeth 2, registering from one face to the other one. The rotor is mounted on a hub 3 secured by a pin 9 to a shaft 10. Said shaft may be supported by bearings 11 mounted in base plates 8, each in a non-magnetic and non-conducting material. Each stator member comprises a plurality of groups of teeth 5 and between said groups a winding of substantially sectorial turns is provided, the continuity of which forms at least one spiral winding 6 ending on terminals 12 and 13 on the member proper (external outputs are not shown). Said groups and said winding are applied over the polar face of a permanent magnet multipole structure. In FIG. 1, the machine includes six permanent magnets 4 carried by a magnetic yoke 7, for instance in a spiral of magnetic tape, mounted on a base plate 8. The polar pieces of the magnets 4, each in a material such as anisotropic coercive ferrite for instance, are shaped to be substantially contiguous over the airgap surface so that the interstices or yokes therebetween are quite narrow and easily filled by a resin for finally smoothing the said airgap facing surface and enabling the application thereon of the magnetic teeth and the winding associated with said groups of teeth. In FIG. 5, the structure is simplified in that the magnetic poles are directly formed by a conventional magnetisation treatment in a ring 14 made of an anisotropic coercive ferrite. As a modification to FIG. 5, the stator may not incorporate the magnetic poles but the rotor may incorpo rate said poles, as it does not make any difference to the operation of the machine that such permanent magnetic poles are on the rotor part or on the stator part of the structure. Of course, the rotor may be made with magnets but this would in most cases unduly load the rotating part of the machine. The operation may be summarized as follows: the rotation of an even distribution of magnetic teeth with respect to the groups of teeth making the modulating poles, ensures the modulation of the permanent magnetic flux at the frequency defined by the number of teeth, of groups of teeth and of poles in the machine, as also by the speed of rotation of the rotor. Said modulation induces an alternating current of corresponding frequency in the stator winding (or windings, such being serially connected). The relative height of the teeth is small, for instance of the order of twoor three-tenths of a millimetre. The thickness of the conductors of the winding is smaller, of the order of one-tenth of a millimetre for instance. Consequently, said winding will be preferably made through the use of a printed circuit technique for obtaining such a dimension and yet capable of carrying a current of suitable value. If possible, the magnetic teeth will be formed integrally with their supporting base piece and this may be done by machining or moulding. When machining or moulding is not possible, the magnetic teeth may be made by the application of a printed circuit technique, engraving in some Way a ring of magnetic and soft material applied over the hard magnetic base piece. If for instance, the engraving comprises the use of an acid, photoetching process, which is able to attack the magnetic material for the etching of a magnetic material (for instance such a material as known in France under the commercial denomination of Anhyster D) and a further acid for attacking the conductor material of the Winding, for instance electrolytic copper (OFHC). The shown winding is made as a single spiral, it may be formed by a multiple spiral when the relative dimensions of the intervals between groups of teeth and of the width of the conductors permit such an arrangement. What I claim is: 1. A high frequency electromechanical generator comprising: a rotor member; and at least one stator member positioned to define with said rotor member a permanent magnetic flux airgap therebetween, one of said members incorporating an inductor multipolar structure, said rotor member comprising, on the airgap face of a magnetic base piece, evenly distributed and constant pitch magnetic teeth and said stator member comprising, on the airgap face of a magnetic base structure, evenly distributed groups of constant pitch magnetic teeth, said groups being spaced apart by one pitch plus a fraction of said pitch, and an evenly developed winding around said groups of teeth. 2. High frequency generator according to claim 1, wherein the machine is of the axial airgap type having a pair of stator members of identical design positioned on opposite sides of the rotor and in registering angular relationship with each other. 3. High frequency generator according to claim 1, wherein the said fraction of pitch is made equal to onehalf of the pitch of the teeth. 4. High frequency generator according to claim 1, wherein at least one of the magnetic base pieces is integral with the magnetic teeth it carries. 5. High frequency generator according to claim 1, wherein one at least of said base pieces comprises a single magnetic member having a magnetic plate overlying the airgap surface of said magnetic base piece, said plate having magnetic teeth formed integrally thereon. 6. High frequency generator according to claim 1, wherein the member incorporating the permanent poles comprises a unitary magnetic base piece in a highly coercive material wherein the said poles comprise magnetized areas of said material. 7. High frequency generator according to claim 1, wherein at least the magnetic base piece carrying said electrical winding comprises at least for the airgap surface thereof, a magnetic insulating material and said winding comprises bare and flat conductors intimately attached to the said insulating surface. 8. High frequency generator according to claim 1, wherein the member incorporating said permanent magnetic poles comprises a magnetic yoke plate, a plurality of permanent magnets equal in number to the number of poles, said magnets being provided with substantially contiguous pole faces. 9. High frequency generator according to claim 8, and including insulating resin moulded in' situ between said magnets and pole faces thereof. 10. High frequency generator according to claim 8, wherein said magnetic teeth are integral with said pole faces and comprise an insulating magnetic material. 11. High frequency generator according to claim 8, said magnetic teeth are integral with a soft magnetic plate secured to said pole face surface. 12. High frequency generator according to claim 1, wherein the thickness of said Winding conductors is made less than the thickness of said magnetic teeth. 13. High frequency generator according to claim 12, wherein said winding comprises at least one complete spiral of rectangular turns uniformly zigzaging between the said groups of teeth. References Cited by the Examiner UNITED STATES PATENTS 1,212,693 1/1917 Ruckgaber 310-268 2,303,293 11/1942 Thomas 310-254 X 2,550,571 4/1951 Litman 310-268 2,722,617 11/1955 Cluwen 310-154 2,734,140 2/1956 Parker 310-268 2,824,275 2/1958 Kober 310-268 2,970,238 l/1961 Swiggett 310-268 FOREIGN PATENTS 579,411 8/ 1946 Great Britain. 693,883 7/ 1940 Germany. ORIS L. RADER, Primary Examiner. MILTON O. HIRSHFIELD, DAVID X. SLINEY, Examiners.

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Patent Citations (9)

    Publication numberPublication dateAssigneeTitle
    DE-693883-CJuly 20, 1940Siemens AgHochfrequenzmaschine der Gleichpolbauart mit einericklung
    GB-579411-AAugust 02, 1946Arthur Mandl, Vickers Electrical Co LtdImprovements in dynamo electric machines
    US-1212693-AJanuary 16, 1917Albert RuckgaberSpeed-regulator for phonographs.
    US-2303293-ANovember 24, 1942Gen ElectricDynamoelectric machine
    US-2550571-AApril 24, 1951Westinghouse Electric CorpAxial-gap motor
    US-2722617-ANovember 01, 1955Hartford Nat Bank & Trust CompMagnetic circuits and devices
    US-2734140-AFebruary 07, 1956parker
    US-2824275-AFebruary 18, 1958Kober WilliamElectric generator and regulator
    US-2970238-AJanuary 31, 1961Printed Motors IncPrinted circuit armature

NO-Patent Citations (0)

    Title

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    Publication numberPublication dateAssigneeTitle
    US-2007228853-A1October 04, 2007Magnetic Torque International, Ltd.Power generating systems
    US-3436571-AApril 01, 1969Trw IncDynamoelectric machine having corresponding ferromagnetic coils on alternating rotor and stator disks
    US-4639626-AJanuary 27, 1987Magnetics Research International CorporationPermanent magnet variable reluctance generator
    WO-2008032298-A1March 20, 2008Wind Concepts LimitedAn alternator
    US-5177392-AJanuary 05, 1993Westinghouse Electric Corp.High efficiency, low reactance disk-type machine including an improved rotor and stator
    US-6348751-B1February 19, 2002New Generation Motors CorporationElectric motor with active hysteresis-based control of winding currents and/or having an efficient stator winding arrangement and/or adjustable air gap
    US-3796039-AMarch 12, 1974P LucienElectric micromotor
    US-9225205-B2December 29, 2015Glassy Metal Technologies Ltd.Method of constructing core with tapered pole pieces and low-loss electrical rotating machine with said core
    US-4672347-AJune 09, 1987The Charles Stark Draper Laboratory, Inc.Multi-speed resolver using ferrite stator and rotor structures
    US-2013134825-A1May 30, 2013Glassy Metal Technologies Ltd.Method of constructing core with tapered pole pieces and low-loss electrical rotating machine with said core
    US-7687956-B2March 30, 2010Magnetic Torque International, Ltd.Drive motor system
    US-RE33628-EJuly 02, 1991Acr Electronics, Inc.Electro-mechanical machine with pie-shaped coils on disc rotor
    US-2007228854-A1October 04, 2007Magnetic Torque International, Ltd.Power generating systems
    US-6590312-B1July 08, 2003Denso CorporationRotary electric machine having a permanent magnet stator and permanent magnet rotor
    US-3869626-AMarch 04, 1975Emi LtdDynamo electric machines
    US-4755703-AJuly 05, 1988Aichi Tokei Denki Co., Ltd.Electric motor
    US-4360751-ANovember 23, 1982Kollmorgen Technologies CorporationFan with integral disc-shaped drive
    US-3777196-ADecember 04, 1973Sigma Instruments IncLow-inertia synchronous inductor motor
    US-7646178-B1January 12, 2010Fradella Richard BBroad-speed-range generator
    US-4143288-AMarch 06, 1979Olympus Optical Co., Ltd.Coreless motor
    US-5229677-AJuly 20, 1993Newport News Shipbuilding And Dry Dock CompanyElectric propulsion motor for marine vehicles
    US-4814654-AMarch 21, 1989Gerfast Sten RStator or rotor based on permanent magnet segments
    US-4757224-AJuly 12, 1988Magnetics Research International Corp.Full flux reversal variable reluctance machine
    US-4578610-AMarch 25, 1986General Electric CompanySynchronous disk motor with amorphous metal stator and permanent magnet rotor and flywheel
    US-2007236092-A1October 11, 2007Magnetic Torque International, Ltd.Power generating systems
    US-4109170-AAugust 22, 1978Hitachi, Ltd., Japan Servo Co., Ltd.Electric motor having frequency generator
    US-2006111191-A1May 25, 2006Magnetic Torque InternationalTorque transfer system and method of using the same
    US-2007262666-A1November 15, 2007Magnetic Torque International, Ltd.Power generating systems
    US-7342337-B2March 11, 2008Magnetic Torque International, Ltd.Power generating systems
    US-2007046117-A1March 01, 2007Magnetic Torque International, Ltd.Torque converter and system using the same
    US-4180296-ADecember 25, 1979Societe Europeenne De PropulsionAxial electromagnetic bearing for a shaft rotating at high speed
    US-7608961-B2October 27, 2009Magnetic Torque International, LtdTorque converter and system using the same
    US-4187441-AFebruary 05, 1980General Electric CompanyHigh power density brushless dc motor
    US-6037696-AMarch 14, 2000Samot Engineering (1992) Ltd.Permanent magnet axial air gap electric machine
    US-5111098-AMay 05, 1992Rockwell International CorporationUnitary rotational speed sensor
    US-4883981-ANovember 28, 1989Gerfast Sten RDynamoelectric machine having ironless stator coil
    US-3525008-AAugust 18, 1970Robert P BurrElectrical wire wound axial air-gap machines
    US-2005258692-A1November 24, 2005Magnetic Torque International, Ltd.Torque converter and system using the same
    US-7808142-B2October 05, 2010E3 Solutions, LlcMultivariable generator and method of using the same
    US-2007216246-A1September 20, 2007Magnetic Torque International, Ltd.Power generating systems
    US-3564313-AFebruary 16, 1971Trans Sonics IncSelf-compensating tachometer generator
    US-2008220882-A1September 11, 2008Magnetic Torque International, Ltd.Torque Converter
    US-5982074-ANovember 09, 1999Advanced Technologies Int., Ltd.Axial field motor/generator
    US-3992641-ANovember 16, 1976Westinghouse Electric CorporationPolyphase disc reluctance motor
    US-3479967-ANovember 25, 1969George CromptonElectric locomotive
    US-2006226725-A1October 12, 2006Magnetic Torque International Ltd.Multivariable generator and method of using the same
    US-7312548-B2December 25, 2007Magnetic Torque International, Ltd.Torque converter and system using the same
    US-7268454-B2September 11, 2007Magnetic Torque International, Ltd.Power generating systems
    US-7279818-B1October 09, 2007Magnetic Torque International Ltd.Power generating systems
    US-4082971-AApril 04, 1978Nihon Radiator Co., Ltd. (Nihon Rajieeta Kabushiki Kaisha)Printed motor
    US-4605873-AAugust 12, 1986David H. RushElectromechanical machine
    US-7336011-B2February 26, 2008Magnetic Torque International Ltd.Power generating systems
    US-3707638-ADecember 26, 1972Alumina Ferrite CorpElectric motor utilizing a ferrite stator of low coerciveness, ferrite rotor of high coerciveness, and photo-electric commutation
    US-7329974-B2February 12, 2008Magnetic Torque International, Ltd.Power generating systems
    US-2010001533-A1January 07, 2010John Leslie JeffersonAlternator
    US-7336010-B2February 26, 2008Magnetic Torque International, Ltd.Power generating systems
    US-3999092-ADecember 21, 1976Canadian General Electric Company LimitedPermanent magnet synchronous dynamoelectric machine
    US-7233088-B2June 19, 2007Magnetic Torque International, Ltd.Torque converter and system using the same
    US-2005099081-A1May 12, 2005Louis ObidniakDisk alternator
    US-2008290750-A1November 27, 2008Magnetic Torque International, Ltd.Drive Motor System
    US-2007024144-A1February 01, 2007Tecobim Inc.Disk alternator
    US-4709180-ANovember 24, 1987The Garrett CorporationToothless stator construction for electrical machines
    US-7279819-B2October 09, 2007Magnetic Torque International, Ltd.Power generating systems
    US-7285888-B1October 23, 2007Magnetic Torque International, Ltd.Power generating systems
    US-2007007835-A1January 11, 2007Magnetic Torque International, Ltd.Power generating systems
    US-B526289-I5February 24, 1976
    WO-9518484-A1July 06, 1995Samot Engineering (1992) Ltd., Friedman, Mark, M.Permanent magnet axial air gap electric machine