CN1220038A - Rotor cover for electric motor - Google Patents

Rotor cover for electric motor Download PDF

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Publication number
CN1220038A
CN1220038A CN97195025.3A CN97195025A CN1220038A CN 1220038 A CN1220038 A CN 1220038A CN 97195025 A CN97195025 A CN 97195025A CN 1220038 A CN1220038 A CN 1220038A
Authority
CN
China
Prior art keywords
rotor
rotor case
rotor core
core
shell
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.)
Pending
Application number
CN97195025.3A
Other languages
Chinese (zh)
Inventor
马克斯·罗梅乌·默比乌斯
马克·杜蒂
埃里范·皮亚齐拉
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.)
Empresa Brasileira de Compressores SA
Original Assignee
Empresa Brasileira de Compressores SA
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 Empresa Brasileira de Compressores SA filed Critical Empresa Brasileira de Compressores SA
Publication of CN1220038A publication Critical patent/CN1220038A/en
Pending legal-status Critical Current

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Classifications

    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02K—DYNAMO-ELECTRIC MACHINES
    • H02K1/00—Details of the magnetic circuit
    • H02K1/06—Details of the magnetic circuit characterised by the shape, form or construction
    • H02K1/22—Rotating parts of the magnetic circuit
    • H02K1/27—Rotor cores with permanent magnets
    • H02K1/2706—Inner rotors
    • H02K1/272—Inner rotors the magnetisation axis of the magnets being perpendicular to the rotor axis
    • H02K1/274—Inner rotors the magnetisation axis of the magnets being perpendicular to the rotor axis the rotor consisting of two or more circumferentially positioned magnets
    • H02K1/2753—Inner rotors the magnetisation axis of the magnets being perpendicular to the rotor axis the rotor consisting of two or more circumferentially positioned magnets the rotor consisting of magnets or groups of magnets arranged with alternating polarity
    • H02K1/278—Surface mounted magnets; Inset magnets
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02K—DYNAMO-ELECTRIC MACHINES
    • H02K1/00—Details of the magnetic circuit
    • H02K1/06—Details of the magnetic circuit characterised by the shape, form or construction
    • H02K1/22—Rotating parts of the magnetic circuit
    • H02K1/27—Rotor cores with permanent magnets
    • H02K1/2706—Inner rotors
    • H02K1/272—Inner rotors the magnetisation axis of the magnets being perpendicular to the rotor axis
    • H02K1/2726—Inner rotors the magnetisation axis of the magnets being perpendicular to the rotor axis the rotor consisting of a single magnet or two or more axially juxtaposed single magnets

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Permanent Field Magnets Of Synchronous Machinery (AREA)

Abstract

A rotor cover for an electric motor, said rotor comprising a rotor core having a lateral surrounding surface and opposite end surfaces; and magnet elements (30) disposed around the rotor core (20) and retained thereon in position by said cover (10), said cover being molded in a single piece, so as to surround at least laterally the core and the faces of the magnet elements (30) which are distinct from those faces seated on the core (20), said cover being circumferentially locked in relation to the rotor core (20) by the interference between at least part of the inner surface of the rotor cover (10) and the outer surface of the rotor core (20).

Description

The rotor case of motor
Invention field
The present invention relates to the rotor case of employed electronic type in the hermetic compressor of refrigerating system.
Background of invention
Motor rotor with permanent magnet, comprise that many being co-axially mounted on reaches the axial magnet of motor on the rotor core, and the rotor case that is configured in described magnet outside, so that make magnet near described iron core, avoid the motor run duration to be subjected to making it from the centrifugal force of rotor core and instantaneous (shearings) the masterpiece time spent that is subjected to making the magnet around the rotor core that tangential skew takes place when magnet, generation is relative between described parts radially reaches tangential skew.Except making magnet near this function of iron core, as mentioned above, rotor case can also be avoided gathering that magnetic patch causes by the effect of thereon power and separate.
In the middle of a known solutions, rotor case is the tubular metal around magnet-core assembly.Though this scheme can make magnet remain on the iron core, the disadvantage of this scheme is induced current to occur, and this induced current will bring electrical loss and resultant motor efficiency to descend.
A kind of scheme that reduces these induced current effects is to utilize the thin outer crust that is obtained by thin corrosion resistant plate.Can make described shell not produce great electrical loss but thickness is reduced to, then except that the structure function that has weakened shell, also be difficult to processing during the manufacture process.
Other some shell schemes also are known, as utilize Kevlar (kevlar), glass fibre, carbon fiber and adhesive or pre-stretching fiber and other material, put on the spot by suitable technology ring and are fixed on the iron core resulting shell of magnet on every side.Therefore and reduce useful life though these schemes have solved magnet is remained on problem on the iron core, these schemes all have some disadvantages, as have provided a kind of shell of fragile structure, and this shell; Perhaps need accurate and/or expensive manufacturing process and very expensive.
Summary of the invention
Therefore, the object of the present invention is to provide a kind of motor rotor shell, this rotor case can also avoid the contingent separation of magnetic patch facing to motor interior, and this rotor case has industrial usability except the long close iron core of useful life period chien shih magnet.
These and other purpose, can realize by a kind of motor rotor shell, described rotor comprises the rotor core with a side ring surface and opposing end faces, and be configured in around the rotor core and remain on magnet device on the iron core appropriate location by housing, described shell forms by one-piece molded, so that be fixed in surperficial different surface on the iron core with it on side direction wound core and the magnet device at least; Described shell tangentially locks with respect to rotor core by the interference fit (interference) between at least a portion inner surface of outer cover and the rotor core outer surface.
The accompanying drawing summary
Present invention is described below with reference to accompanying drawings, wherein:
Fig. 1 and 1a schematically illustrate according in the rotor case scheme of the present invention with the form of profile, around the rotor case of magnet iron pieces different around the rotor core;
Fig. 2 and 2a schematically illustrate in the rotor case scheme according to Fig. 1, around the rotor case of magnet iron pieces different around the rotor core with the form of sectional arrangement drawing;
Fig. 3 and 3a schematically illustrate the rotor case of another program according to the present invention respectively with the form of profile and sectional arrangement drawing, this rotor case comprises magnet device, and be installed in rotor core around;
Fig. 4,4a, 4b and 4c schematically illustrate the shape that is configured in rotor core magnet on every side in rotor case scheme of the present invention with the form of sectional arrangement drawing; And
Fig. 5 schematically illustrates according to of the present invention around the magnet around the rotor core and be provided with the rotor case of lock tab with the form of profile.
Realize best mode of the present invention
The present invention relates to rotor case 10, this rotor case 10 is used to have rotor core 20 such motor rotors, rotor core 20 assembles around the part of motor reel at least and it is fixed with magnet device 30 on every side, magnet device 30 is under the effect of rotor case 10, and is usually along the circumferential direction spaced-apart and remain on rotor core 20 lateral surfaces 21 with the form of magnetic patch.
Shell of the present invention obtains by molded (injection molding or casting), comprises magnet (Fig. 1-2 and 4-5), contains magnet (Fig. 3 and 3a) or limited by magnet when magnet casts in around the iron core.In in the end a kind of situation following time,, shell is to obtain a magnet ring in the mould by directly magnetic material being cast in around the iron core or being molded into, and utilizes bonding, interference fit or other suitable technology that this magnet ring is fixed on afterwards and obtains around the rotor core.By injection molding obtain rotor case can be directly around rotor core or realize in a mould that in advance afterwards that this shell utilization is suitable technology is fixed on the rotor.
In the structure chart shown in Fig. 3 and the 3a, rotor case 10 comprises with granular magnetic material, the best magnet device 30 that exists with the magnetic form, granular magnetic material preferably magnetic is included in the adhesives piece, this adhesives piece define shell and for example inject the mold that has rotor core in it around.
In a kind of distressed structure of this scheme, magnet device comprises in the enclosure, and shell can be obtained by rare earth, in order to be molded as shell, utilizes a kind of adhesives to bond together magnet device.
According to structure chart shown in the present, around unshowned armature spindle a certain extends axially line, the rotor case 10 that utilizes one of mold and casting process to carry out coaxial assembling is arranged, for side direction wound core and magnet device 30 at least be fixed in iron core 20 on the surface different surface, rotor case 10 has a columned lateral surface 11 and a medial surface 12, its shape and iron core and/or by shell around the shape of magnet segment match.
Rotor case 10 of the present invention, as shown in Fig. 1-2 a, preferably form by one-piece molded, and provide a pair of terminal flange 13, each flange is anchored on respectively in a pair of end face of each magnet device 30 on the corresponding end face, and preferably be anchored on the corresponding end-faces of the rotor core 20 that stretches to the armature spindle zone, so that shell 10 is axially locked with respect to rotor core 20.In this structure, shell-magnet-rotor core assembly for example can comprise the retaining element 40 as shown in Fig. 2 a.
In order to realize the present invention, rotor case 10 can be provided with the terminal flange with arbitrary dimension, and the size of flange can be that zero size value when shell has only a sidewall is to illustrated full-size value.
At the motor run duration, for fear of tangential motion relative between the parts, can utilize at least one surface that limited by rotor case 10 inner surfaces and the interference fit between an adjacent rotors iron core 20 outer surfaces to obtain tangential locking between rotor case 10 and the rotor core 20, described surface is at least by one of the side of each parts and surface that opposing end faces limited, and described parts are limited by shell and rotor core.Interference fit is to obtain by the surperficial projection of at least one in shell 10 and rotor core 20 parts is assembled in the corresponding recesses that is arranged on described another parts.Realizing that surperficial projection comprises the lateral parts of surrounding rotor iron core on this point of the present invention, when rotor core be have the finite population side polygon the time, described lateral parts is positioned at the outside of polygon inscribed circle.When surperficial projection has infinite number side (circumference), for example can utilize be arranged at least one surface as shown in Fig. 3 and 3a, that limited by rotor case 10 inner surfaces or by rotor core 20 outer surfaces, with radially and/or the surperficial projection that exists of the form of axial rib realize locking.
In rotor case 10 structures, rotor case 10 is provided with around magnet device 30, wherein magnet device be fixed on around the rotor core 20 and in a circumferential direction apart from one another by the magnetic patch form exist, rotor case 10 comprises radial rib 14, this radial rib 14 is limited during the shell manufacture process around rotor core 20 and the magnet 30, and from rotor case 10 medial surfaces 12, each rib defines a spacer element, is fixed with the limit, longitudinal side that faces of two tangential adjacent magnets on it.Radial rib 14 has occupied at least a portion of rotor case 10 medial surfaces 12 and preferably whole longitudinal size.
In a distressed structure, radial rib 14 arbitrary surface or two surfaces in rotor case 10 inner surfaces and rotor core 20 outer surfaces begin to be provided with, when comprising the magnet spacer element in the structure of rotor core 20, radial rib 14 preferably occupies the whole longitudinal size of rotor core 20.In another distressed structure, surperficial projection further defines axial rib, and these axial rib free rotor iron core 20 terminal at least one parts that is limited by rotor case 10 terminal flanges 13 that reach begin to be provided with.
In the rotor housing structure that comprises magnet device 30 as shown in the figure, the surface projection comprises radial rib 23, this radial rib 23 is provided with to the small part longitudinal size along rotor core 20 outer surfaces, and during its manufacture process, this radial rib 23 acts in the corresponding recesses 15 that is limited on rotor case 10 medial surfaces 12.Should be appreciated that and to realize desired locking by surperficial projection that this surface projection comprises the radial rib 23 that is provided with at the beginning of the blade of at least one self-forming rotor core, and surperficial thus projection has only occupied rotor core lateral surface one shorter size.
In another structure chart of the present invention as shown in Figure 5, radial rib 14 acts in the groove 25 that is arranged on rotor core 20 main bodys, groove 25 preferably is the form of female locking element, the convex locking member that is limited by radial rib 14 during effect has rotor case 10 to make on it.
The shape of radial rib and size are to be determined by the function of the number of poles of rotor size, motor, the line of flux in the rotor or the like and manufacturing process (difficulty, cost etc.).Except that shape shown (Fig. 5), have other structures of same good result or have angle of chamfer or the polygon of fillet, or have a conical basal plane.
Rotor case 10 can further comprise at least one inner annular projection 16, and this projection stretches out from the inner surface radial direction of rotor case 10, and will axially separate along the magnet segment 30 of rotor core 20 longitudinal sizes configuration.16 sizings of inner annular projection should make the side-play amount minimum of the magnetic material of surrounding rotor, thereby make the electrical loss of motor reach minimum.
Except providing between rotor case and the rotor core axially and tangentially locking, existing rib and projection, because its average thickness increases and defines a structural hull shape for rotor case 10, think that rotor case 10 provides higher structural drag.
In rotor case 10 structures around magnet 30, for rotor case 10 is had than the long life-span and in order to make rotor case 10 have higher maintenance effect on magnet, magnet is abutted against on the rotor core 20, magnet 30 should be prismatic, cut in order to make its wedge angle reduce to its top of young pathbreaker, the top that is angle of chamfer or fillet as shown in Fig. 4 and 4b, preferably the inside and outside radius of magnet is eccentric this shape.Illustrated have eccentric in the magnet arrangement of outer radius, the skew of these radiuses should be got certain size so that make the motor run duration act on power minimum on the shell.In this structure, although the shape of magnet makes that the electrical loss of motor is very low, increased the thickness of rotor case 10, and improved its structure function therefrom.

Claims (14)

1. motor rotor shell, described rotor comprises the rotor core (20) with side ring surface and opposing end faces, and be configured in rotor core (20) and remain on magnet device (30) on the rotor core appropriate location on every side and by described shell (10), it is characterized in that: described shell forms by one-piece molded, so that side direction wound core and magnet device (30) are gone up with it and be fixed in surperficial different surface on the iron core (20) at least; Described shell by rotor case (10) inner surface at least a portion and the interference fit between rotor core (20) outer surface with respect to the tangential locking of rotor core (20).
2. according to the rotor case of claim 1, it is characterized in that: the interference fit between at least a portion of rotor case (10) inner surface and rotor core (20) outer surface is to be assembled to be arranged on another described parts by the surperficial projection at least one parts that will be limited by rotor case (10) and rotor core (20) to obtain in the corresponding grooves.
3. according to the rotor case of claim 2, it is characterized in that: the side ring surface of rotor core is the polygon with limited side, and described surperficial projection comprises the side ring surface part that is positioned at the polygon inscribed circle outside.
4. according to the rotor case of claim 2 or 3, it is characterized in that: surperficial projection comprises the radial rib (14,23) that at least one parts that free shell (10) medial surface (12) and rotor core (20) annular side (21) are limited begin to be provided with.
5. according to the rotor case of claim 4, it is characterized in that: each radial rib (14,23) defines a dividing element, and this dividing element is fixed the relatively vertically side of two adjacent magnets (30) relatively.
6. according to the rotor case of claim 5, it is characterized in that: radial rib (14) occupied rotor case (10) inner surface (12) to the small part longitudinal size.
7. according to the rotor case of claim 4, it is characterized in that: radial rib (23) is provided with along at least a portion of rotor core (20) outer surface (21), and act on described shell molded during in the fixed radial groove of the shell upper limit (15), described shell comprises magnet device (30) with the single-piece form.
8. according to the rotor case of claim 4, it is characterized in that: radial rib (14) is provided with along at least a portion of rotor case (10) medial surface (12), acts in the groove that is female locking element form (25) that is arranged on the rotor core (20) with convex-concave locking member form.
9. according to the rotor case of claim 1, it is characterized in that: it disposes a pair of terminal flange (13), each flange is fixed in around on the associated end of the magnet of rotor core (20) part (22), so that the axial locking with respect to shell (10) is provided.
10. according to the rotor case of claim 9, it is characterized in that: it further has an interior state ring projection (16), and this projection stretches out from the inner surface (12) of shell (10), so that magnet (30) partial axial separation is opened.
11. the rotor case according to claim 10 is characterized in that: magnet device (30) is a prismatic, and its head portion cuts so that make tip portion reduce to minimum.
12. the rotor case according to claim 1 is characterized in that: the making of rotor case (10) is to realize by one of casting and molding process in the mould that contains rotor core (20) at least.
13. the rotor case according to claim 12 is characterized in that: be assembled on the rotor core after it is made.
14. the rotor case according to claim 1 is characterized in that: comprise at shell under the situation of magnet device (30) that this shell is made by the granular magnetic material that utilizes the adhesives gummed to form.
CN97195025.3A 1996-05-29 1997-05-23 Rotor cover for electric motor Pending CN1220038A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
BRPI96017562 1996-05-29
BR9601756A BR9601756A (en) 1996-05-29 1996-05-29 Electric motor rotor cover

Publications (1)

Publication Number Publication Date
CN1220038A true CN1220038A (en) 1999-06-16

Family

ID=4064105

Family Applications (1)

Application Number Title Priority Date Filing Date
CN97195025.3A Pending CN1220038A (en) 1996-05-29 1997-05-23 Rotor cover for electric motor

Country Status (5)

Country Link
EP (1) EP0913022A1 (en)
JP (1) JP2001516550A (en)
CN (1) CN1220038A (en)
BR (1) BR9601756A (en)
WO (1) WO1997045917A1 (en)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102835008A (en) * 2010-04-09 2012-12-19 大陆汽车有限责任公司 Rotor
CN104362779A (en) * 2014-11-07 2015-02-18 上海法雷奥汽车电器系统有限公司 Claw pole motor rotor structure efficiently utilizing compressed-powder iron core material to lower iron loss
CN107431421A (en) * 2015-04-09 2017-12-01 大众汽车有限公司 Motor
CN110538622A (en) * 2019-09-18 2019-12-06 刘艳 Chemical reaction kettle
CN110999031A (en) * 2017-08-03 2020-04-10 Lg伊诺特有限公司 Motor with a stator having a stator core
CN112003406A (en) * 2015-02-16 2020-11-27 欧亚瑟有限公司 Pump with electric motor

Families Citing this family (13)

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US6078121A (en) * 1997-02-21 2000-06-20 Emerson Electric Co. Rotor assembly for a rotating machine
DE19838661A1 (en) * 1998-08-25 2000-03-02 Mannesmann Vdo Ag Electric motor and use of an electric motor
GB2353902A (en) * 1999-08-28 2001-03-07 Aisin Seiki Canned magnet structure for motor
DE10041329A1 (en) * 2000-08-23 2002-03-14 Siemens Ag Armature excited by permanent magnets for use with an electrical driving mechanism e.g. for machine tools, uses pole gaps to increase magnetic lateral resistance in armature stampings.
GB0130602D0 (en) * 2001-12-21 2002-02-06 Johnson Electric Sa Brushless D.C. motor
JP2003199274A (en) * 2001-12-25 2003-07-11 Hitachi Ltd Rotor, its manufacturing method, and rotating electric machine
JP2006025509A (en) * 2004-07-07 2006-01-26 Nsk Ltd Motor for electric power steering system and electric power steering system
EP1753113B1 (en) 2005-08-11 2012-10-10 Josef Ott Stator molding
DE102010041585A1 (en) * 2010-09-29 2012-03-29 Siemens Aktiengesellschaft Rotor for use as inner rotor of e.g. linear electric machine for permanent synchronous generator of wind power station, has permanent magnets mounted on periphery of rotor body where each pocket is intractable and connected with rotor body
US9130426B2 (en) * 2011-10-31 2015-09-08 Regal Beloit America, Inc. Permanent magnet rotors and methods of assembling the same
DE102013007235A1 (en) * 2013-04-26 2014-10-30 SIEVA d.o.o. - poslovna enota Idrija Brushless inner rotor DC motor
DE102017103936A1 (en) 2017-02-24 2018-08-30 Minebea Mitsumi Inc. Rotor with a bearing
KR102498790B1 (en) 2020-11-23 2023-02-13 포항공과대학교 산학협력단 2-segment quasi-Halbach rotor of motor

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JPS60102854A (en) * 1983-11-07 1985-06-07 Sanyo Electric Co Ltd Sealed motor compressor
JPS61288758A (en) * 1985-06-14 1986-12-18 Sanyo Electric Co Ltd Permanent magnet type rotor
GB9302496D0 (en) * 1993-02-09 1993-03-24 Johnson Electric Sa Permanent magnet rotor

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102835008A (en) * 2010-04-09 2012-12-19 大陆汽车有限责任公司 Rotor
US9024495B2 (en) 2010-04-09 2015-05-05 Continental Automotive Gmbh Rotor
CN102835008B (en) * 2010-04-09 2015-09-16 大陆汽车有限责任公司 Rotor
CN104362779A (en) * 2014-11-07 2015-02-18 上海法雷奥汽车电器系统有限公司 Claw pole motor rotor structure efficiently utilizing compressed-powder iron core material to lower iron loss
CN104362779B (en) * 2014-11-07 2017-10-10 上海法雷奥汽车电器系统有限公司 A kind of efficient utilization dust core material is to reduce the claw-pole motor rotor structure of iron loss
CN112003406A (en) * 2015-02-16 2020-11-27 欧亚瑟有限公司 Pump with electric motor
CN107431421A (en) * 2015-04-09 2017-12-01 大众汽车有限公司 Motor
CN110999031A (en) * 2017-08-03 2020-04-10 Lg伊诺特有限公司 Motor with a stator having a stator core
CN110999031B (en) * 2017-08-03 2022-04-19 Lg伊诺特有限公司 Motor
CN110538622A (en) * 2019-09-18 2019-12-06 刘艳 Chemical reaction kettle

Also Published As

Publication number Publication date
EP0913022A1 (en) 1999-05-06
JP2001516550A (en) 2001-09-25
WO1997045917A1 (en) 1997-12-04
BR9601756A (en) 1998-09-29

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