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US4795933A Expired / Lapsed US ⏱️ 0.0 years remaining

Salient-pole rotary electric machine

Assignee: Hitachi Ltd
•
Filing: 1983-07-28
•
Granted: 1989-01-03
•
Expires: 2003-07-28
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Abstract

Abstract A salient-pole rotary electric machine comprises a stator including a stator core formed with a plurality of ventilation ducts spaced apart by a predetermined distance in its axial direction and extending in its radial direction, and a stator winding would around the stator core, and a rotor including a rotor shaft, a rotor rim rotatable together with the rotor shaft, a plurality of salient field poles disposed on the outer periphery of the rotor rim in circumferentially spaced apart relation and extending in the axial direction of the rotor rim, and cooling gas passages defined between every adjacent salient field poles. In the rotary electric machine, a closure member is bured in each of the cooling gas passages between the salient field poles to extend from one of the axial ends to the center of the cooling gas passage, and the closure members are disposed between the adjacent salient field poles in a relation alternate with each other in the axial direction of the salient field poles. The alternate arrangement of the closure members reduces the mechanical losses of the salient-pole rotary electric machine and ensures uniform cooling of the stator throughout the axial length of the stator.

Inventors

  • 👤 Koichi Sakai

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 00:57
CPC Classifications
H; H02; H02K; H02K9/00; H02K9/14; H02K9/18; Y; Y10; Y10S; Y10S174/00; Y10S174/13; Y10S174/14; Y10S174/19; Y10S174/20; Y10S174/32

Claims Analysis

Total Claims: 3
Claim 1
Independent Claim 232 words
A rotary electric machine of a salient pole type comprising a stator including a stator core and a stator winding wound around said stator core, said stator core being formed with a plurality of ventilation ducts spaced apart by a predetermined distance in its axial direction and extending in its radial direction, and a rotor including a rotor shaft, a rotor rim rotatable together with said rotor shaft, a plurality of salient field poles disposed on the outer periphery of said rotor rim in circumferentially spaced apart relationship and extending in the axial direction of said rotor rim, and cooling gas passages defined between every adjacent salient field pole, wherein a closure member having a total length about one-half that of the salient field pole is buried in each of said cooling gas passages between said salient field poles to extend from one of the axial ends to the center of said cooling gas passage, said closure members are being disposed between the adjacent salient field poles in an alternate relationship with each other in the axial direction of said salient field poles, and said closure members have a radial width such that each closure member extends from approximately an outer peripheral surface of the field poles to an outer peripheral surface of the rotor rim whereby cooling gas is prevented from flowing in an axial direction of the respective closure members.
Claim 2
Dependent Claim 232 words
A rotary electric machine of a salient pole type comprising a stator including a stator core and a stator winding wound around said stator core, said stator core being formed with a plurality of ventilation ducts spaced apart by a predetermined distance in its axial direction and extending in its radial direction, and a rotor including a rotor shaft, a rotor rim rotatable together with said rotor shaft, a plurality of salient field poles disposed on the outer periphery of said rotor rim in circumferentially spaced apart relationship and extending in the axial direction of said rotor rim, and cooling gas passages defined between every adjacent salient field pole, wherein a closure member having a total length about one-half that of the salient field pole is buried in each of said cooling gas passages between said salient field poles to extend from one of the axial ends to the center of said cooling gas passage, said closure members are being disposed between the adjacent salient field poles in an alternate relationship with each other in the axial direction of said salient field poles, and said closure members have a radial width such that each closure member extends from approximately an outer peripheral surface of the field poles to an outer peripheral surface of the rotor rim whereby cooling gas is prevented from flowing in an axial direction of the respective closure members.
Claim 3
Dependent Claim 25 words
A rotary electric machine of the salient pole type as claimed in claim 1, wherein said closure members are made of an electrical insulating material.

References Cited (Backward Citations)

US2899573A Cited
US2974239A Cited
US3160770A Cited
US3514647A Cited
GB1396327A Cited
US3932778A Cited
DE2841231A1 Cited
JPS54129407A Cited
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USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1992-01-03 1992-07-04 1993-01-03 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1996-01-03 1996-07-04 1997-01-03 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2000-01-03 2000-07-04 2001-01-03 $7700.00 Window Closed / Lapsed

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