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US4039853A Expired / Lapsed US ⏱️ 0.0 years remaining

Magnetizing device for permanent magnet motor for electric vehicle

Assignee: Hitachi Ltd
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Filing: 1975-09-29
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Granted: 1977-08-02
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Expires: 1995-09-29
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Abstract

Abstract A magnetizing device for a permanent magnet motor used for driving an electric vehicle in which a magnetizing coil is wound around the permanent magnet of the permanent magnet motor, and means are provided for detecting a specific step such as manipulation of the key switch in the electric vehicle in a series of predetermined steps required for the operation of the electric vehicle. In response to the detection of such specific manipulation, magnetizing current is supplied to the magnetizing coil from the battery of the electric vehicle so that the permanent magnet can be automatically magnetized.

Inventors

  • 👤 Osamu Koizumi
  • 👤 Shigeki Saito
  • 👤 Shotaro Naito

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 06:56
CPC Classifications
H; H02; H02K; H02K15/00; H02K15/02; H02K15/03; H01; H01F; H01F13/00; H01F13/003; Y; Y02; Y02T; Y02T10/00; Y02T10/60; Y02T10/64

Claims Analysis

Total Claims: 5
Claim 1
Independent Claim 80 words
In an electric vehicle equipped with a main dc power source, a permanent magnet motor, and a chopper controlling the current supplied from said main dc power source to said permanent magnet motor, a magnetizing device comprising a magnetizing coil wound around the permanent magnet of said permanent magnet motor, and means for supplying magnetizing current to said magnetizing coil in response to a specific step in a series of predetermined steps required for the operation of the electric vehicle.
Claim 2
Dependent Claim 80 words
In an electric vehicle equipped with a main dc power source, a permanent magnet motor, and a chopper controlling the current supplied from said main dc power source to said permanent magnet motor, a magnetizing device comprising a magnetizing coil wound around the permanent magnet of said permanent magnet motor, and means for supplying magnetizing current to said magnetizing coil in response to a specific step in a series of predetermined steps required for the operation of the electric vehicle.
Claim 3
Dependent Claim 43 words
A magnetizing device as claimed in Claim 1, wherein said magnetizing current is supplied to said magnetizing coil through said chopper, and the circuit supplying said magnetizing current to said magnetizing coil is opened when the output current of said chopper is nil.
Claim 4
Dependent Claim 116 words
In an electric vehicle equipped with a main dc power source, a permanent magnet motor, a chopper, an accelerator pedal, a key switch for turning on the power source circuit whens turned on, and a chopper controller operative in response to the depression of said accelerator pedal for controlling said chopper thereby controlling the current supplied from said main dc power source to said permanent magnet motor, a magnetizing device comprising a magnetizing coil wound around the permanent magnet of said permanent magnet motor, and means for supplying magnetizing current to said magnetizing coil for a predetermined period of time in response to the initial depression of said accelerator pedal after turning on said key switch.
Claim 5
Dependent Claim 116 words
In an electric vehicle equipped with a main dc power source, a permanent magnet motor, a chopper, an accelerator pedal, a key switch for turning on the power source circuit whens turned on, and a chopper controller operative in response to the depression of said accelerator pedal for controlling said chopper thereby controlling the current supplied from said main dc power source to said permanent magnet motor, a magnetizing device comprising a magnetizing coil wound around the permanent magnet of said permanent magnet motor, and means for supplying magnetizing current to said magnetizing coil for a predetermined period of time in response to the initial depression of said accelerator pedal after turning on said key switch.

References Cited (Backward Citations)

US2609411A Cited
US2529049A Cited
US3678436A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1980-08-01 1981-01-31 1981-08-02 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1984-08-01 1985-01-31 1985-08-02 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1988-08-01 1989-01-31 1989-08-02 $7700.00 Window Closed / Lapsed

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