EP0096868A1
Expired / Lapsed
EP
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Permanent magnet type motor
Assignee: Hitachi Ltd
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Filing: 1983-06-10
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Granted: —
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Expires: 2003-06-10
Abstract
Abstract A permanent magnet type motor having a stator (1) which comprises a yoke (4), a plurality of main magnetic poles (2) made of permanent magnets, and a plurality of auxiliary magnetic poles (3), each of the main magnetic poles (2) and each of the auxiliary magnetic poles (3) being juxtaposed on the inner peripheral surface of the yoke (4), wherein each of the auxiliary magnetic poles (3) has an axial length (Lp) larger than the thickness (La) of an armature core and smaller than the axial length (Lm) of each of the main magnetic poles (2), wherein each of the main magnetic poles (2) has an inner diameter (Dp) smaller than the inner diameter (Ds) of each of the auxiliary magnetic poles (3), wherein each of the main poles (2), before being secured on the yoke (4), is machined to have the inner diameter (Dp) smaller than the predetermined inner diameter by a thickness (8) to be machined, and wherein each of the main magnetic poles is machined to have the predetermined inner diameter after it has been secured together with each of the auxiliary magnetic poles (3) onto the yoke (4).
Inventors
- 👤 Tosio Tomite
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-01 13:48
CPC Classifications
H; H02; H02K; H02K15/00; H02K15/02; H02K15/03; H02K23/00; H02K23/02; H02K23/04; Y; Y10; Y10T; Y10T74/00; Y10T74/13; Y10T74/131
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
96 words
A permanent magnet type motor having a stator (1) which comprises a yoke (4), a plurality of main magnetic poles (2) made of permanent magnets, and a plurality of auxiliary magnetic poles (3), each of said main magnetic poles (2) and each of said auxiliary magnetic poles (3) being juxtaposed on the inner peripheral surface of said yoke (4), wherein each of said auxiliary magnetic poles (3) has an axial length (Lp) larger than a thickness (La) of an armature core and smaller than an axial length (Lm) of each of said main magnetic poles (2).
Claim 2
Dependent Claim
96 words
A permanent magnet type motor having a stator (1) which comprises a yoke (4), a plurality of main magnetic poles (2) made of permanent magnets, and a plurality of auxiliary magnetic poles (3), each of said main magnetic poles (2) and each of said auxiliary magnetic poles (3) being juxtaposed on the inner peripheral surface of said yoke (4), wherein each of said auxiliary magnetic poles (3) has an axial length (Lp) larger than a thickness (La) of an armature core and smaller than an axial length (Lm) of each of said main magnetic poles (2).
Claim 3
Dependent Claim
59 words
A permanent magnet type motor according to claim 1, wherein each of said auxiliary magnetic poles (3) has an axial length (Lp) approximately 1.1 to 1.3 times a thickness (La) of said armature core, and each of said main magnetic poles (2) has an axial length (Lm) approximately 1.5 to 2.0 times the thickness (La) of said armature core.
Claim 4
Dependent Claim
99 words
A permanent magnet type motor according to claim 1, wherein each of said main magnetic poles (2) is formed to have an increasing coercive force and decreasing residual flux density toward an end of a demagnetizing field region (2a) due to armature reaction and an increasing residual flux density and decreasing coercive force toward an end of a magnetizing field region (2b), with a portion of said demagnetizing field region (2a) with a larger coercive force and a portion of said magnetizing field region (2b) with a higher residual flux density being formed with gradual slopes of magnetic characteristics.
Claim 5
Dependent Claim
155 words
A permanent magnet type motor having a stator (1) which comprises a yoke (4), a plurality of main magnetic poles (2) made of permanent magnets, and a plurality of auxiliary magnetic poles (3), each of said main magnetic poles (2) and each of said auxiliary magnetic poles (3) being juxtaposed on the inner peripheral surface of said yoke (4), wherein each of said main magnetic poles (2) has an inner diameter (Dp) smaller than an inner diameter (Ds) of each of said auxiliary magnetic poles (3), wherein each of said main poles (2), before being secured on said yoke (4), is machined to have the inner diameter (Dp) smaller than a predetermined inner diameter by a thickness (6) to be machined, and wherein each of said main magnetic poles is machined to have the predetermined inner diameter after it has been secured together with each of said auxiliary magnetic poles (3) onto said yoke (4).
Claim 6
Dependent Claim
155 words
A permanent magnet type motor having a stator (1) which comprises a yoke (4), a plurality of main magnetic poles (2) made of permanent magnets, and a plurality of auxiliary magnetic poles (3), each of said main magnetic poles (2) and each of said auxiliary magnetic poles (3) being juxtaposed on the inner peripheral surface of said yoke (4), wherein each of said main magnetic poles (2) has an inner diameter (Dp) smaller than an inner diameter (Ds) of each of said auxiliary magnetic poles (3), wherein each of said main poles (2), before being secured on said yoke (4), is machined to have the inner diameter (Dp) smaller than a predetermined inner diameter by a thickness (6) to be machined, and wherein each of said main magnetic poles is machined to have the predetermined inner diameter after it has been secured together with each of said auxiliary magnetic poles (3) onto said yoke (4).
Claim 7
Dependent Claim
100 words
A permanent magnet type motor according to claim 4, wherein each of said main magnetic poles (2) is formed to have an increasing coercive force and decreasing residual flux density toward an end of a demagnetizing magnetic field region (2a) due to armature reaction and an increasing residual flux density and decreasing coercive force toward an end of a magnetizing field region (2b), with a portion of said demagnetizing field region (2a) with a larger coercive force and a portion of said magnetizing field region (2b) with a higher residual flux density being formed with gradual slopes of magnetic characteristics.
Claim 8
Dependent Claim
193 words
A permanent magnet type motor having a stator (1) which comprises a yoke (4), a plurality of main magnetic poles (2) made of permanent magnets, and a plurality of auxiliary magnetic poles (3), each of said main magnetic poles (2) and each of said auxiliary magnetic poles (3) being juxtaposed on the inner peripheral surface of said yoke (4), wherein each of said auxiliary magnetic poles (3) has an axial length (Lp) larger than a thickness (La) of an armature core and smaller than an axial length (Lm) of each of said main magnetic poles (2), wherein each of said main magnetic poles (2) has an inner diameter (Dp) smaller than an inner diameter (Ds) of each of said auxiliary magnetic poles (3), wherein each of said main magnetic poles (2), before being secured on said yoke (4), is machined to have the inner diameter (Dp) smaller than a predetermined inner diameter by a thickness (6) to be machined, and wherein each of said main magnetic poles is machined to have the predetermined inner diameter after it has been secured together with each of said auxiliary magnetic poles (3) onto said yoke (4).
Claim 9
Dependent Claim
193 words
A permanent magnet type motor having a stator (1) which comprises a yoke (4), a plurality of main magnetic poles (2) made of permanent magnets, and a plurality of auxiliary magnetic poles (3), each of said main magnetic poles (2) and each of said auxiliary magnetic poles (3) being juxtaposed on the inner peripheral surface of said yoke (4), wherein each of said auxiliary magnetic poles (3) has an axial length (Lp) larger than a thickness (La) of an armature core and smaller than an axial length (Lm) of each of said main magnetic poles (2), wherein each of said main magnetic poles (2) has an inner diameter (Dp) smaller than an inner diameter (Ds) of each of said auxiliary magnetic poles (3), wherein each of said main magnetic poles (2), before being secured on said yoke (4), is machined to have the inner diameter (Dp) smaller than a predetermined inner diameter by a thickness (6) to be machined, and wherein each of said main magnetic poles is machined to have the predetermined inner diameter after it has been secured together with each of said auxiliary magnetic poles (3) onto said yoke (4).
Claim 10
Dependent Claim
58 words
A permanent magnetic type motor according to claim 6, wherein each of said auxiliary magnetic poles (3) has an axial length (Lp) approximately 1.1 to 1.3 times a thickness of said armature core, and each of said main magnetic poles (2) has an axial length (Lm) approximately 1.5 to 2.0 times the thickness (La) of said armature core.
Claim 11
Dependent Claim
99 words
A permanent magnet type motor according to claim 6, wherein each of said main magnetic poles (2) is formed to have an increasing coercive force and decreasing residual flux density toward an end of a demagnetizing field region (2a) due to armature reaction and an increasing residual flux density and decreasing coercive force toward an end of a magnetizing field region (2b), with a portion of said demagnetizing field region (2a) with a larger coercive force and a portion of said magnetizing field region (2b) with a higher residual flux density being formed with gradual slopes of magnetic characteristics.
References Cited (Backward Citations)
US3361917A
Cited
FR2245112A1
Cited
FR2268377A1
Cited
FR2322473A1
Cited
EP0048966A1
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EP0078012A1
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