US4464595A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Field system of magnet type D.C. motor having magnetic flux reducing pole pieces
Assignee: Mitsubishi Electric Corp
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Filing: 1982-12-20
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Granted: 1984-08-07
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Expires: 2002-12-20
Abstract
Abstract In a field system of a magnet type D.C. motor constructed of a cylindrical yoke and a plurality of pole pieces, each of which is made of a permanent magnet member bonded to the inner peripheral surface of the yoke, an improved field system wherein each pole piece is formed with a recess along its central part. The yoke is provided with bent portions protruding inwards of the yoke, in correspondence with each recess, and the bent portions are held in engagement with the recess through an elastic member.
Inventors
- 👤 Isao Hamano
- 👤 Toshinori Tanaka
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 12:53
CPC Classifications
H; H02; H02K; H02K23/00; H02K23/02; H02K23/04; F; F02; F02N; F02N11/00; H02K1/00; H02K1/06; H02K1/12; H02K1/17; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49009; Y10T29/49826; Y10T29/49908; Y10T29/49925
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
100 words
A field system of a magnet type D.C. motor comprising: a cylindrical yoke, a plurality of pole pieces each of which is made of a permanent magnet member bonded to an inner peripheral surface of said yoke, each pole piece having a recess formed therein which extends along a central part thereof, and a plurality of pairs of bent portions provided in said yoke each pair of bent portions in correspondence with each of said recess, and which are protruded inwards of said yoke and held in engagement with both side wall surfaces of said recess through an elastic member.
Claim 2
Dependent Claim
100 words
A field system of a magnet type D.C. motor comprising: a cylindrical yoke, a plurality of pole pieces each of which is made of a permanent magnet member bonded to an inner peripheral surface of said yoke, each pole piece having a recess formed therein which extends along a central part thereof, and a plurality of pairs of bent portions provided in said yoke each pair of bent portions in correspondence with each of said recess, and which are protruded inwards of said yoke and held in engagement with both side wall surfaces of said recess through an elastic member.
Claim 3
Dependent Claim
19 words
The field system according to claim 1, wherein said recess extends in the axial direction of said cylindrical yoke.
Claim 4
Dependent Claim
22 words
The field system according to claim 1, wherein each of said pairs of bent portions defines a slit in said cylindrical yoke.
Claim 5
Dependent Claim
30 words
The field system according to claim 1, wherein each elastic member comprises a cushion fastened between each pole piece and a corresponding pair of protruding bent portions of said yoke.
References Cited (Backward Citations)
US2903610A
Cited
US3110079A
Cited
GB1118604A
Cited
US3497735A
Cited
FR2269229A1
Cited
US4364406A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-08-07 | 1988-02-06 | 1988-08-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-08-07 | 1992-02-06 | 1992-08-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-08-07 | 1996-02-06 | 1996-08-07 | $7700.00 | Window Closed / Lapsed |