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US 5,003,208 AGranted
Miniature motor having positive-coefficient thermistor
AssigneeMabuchi Motor Co., Ltd.
InventorsNobuhiro Hama, Tsutomu Saya, Sigeru Mitamura
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AssigneeMabuchi Motor Co., Ltd.
InventorsNobuhiro Hama, Tsutomu Saya, Sigeru Mitamura
Estimating the term…
A miniature motor having a positive temperature coefficient thermistor comprising a stator having a permanent magnet serving as a field, a rotor formed by winding a plurality of rotor windings on a rotor core, brushes supported by a motor cover plate for feeding current to the rotor windings by making contact with a commutator, positive temperature coefficient thermistor for controlling current to the rotor windings, in which the positive temperature coefficient thermistor has one pole on one pole surface thereof, and a plurality of independent split poles corresponding to the rotor windings on the other pole surface thereof, and is fitted to an end face of the rotor core; the rotor windings being connected to the split poles of the positive-coefficient thermistor in such a manner as to be connected in series with the split poles of the positive-coefficient thermistor.
A miniature motor, comprising:
A miniature motor as set forth in claim (1) wherein said positive temperature coefficient thermistor has the same shape as said rotor core.
A miniature motor as set forth in claim (1) wherein there is an insulating material between said positive-coefficient thermistor and said rotor core.
A miniature motor as set forth in claim (1) wherein said rotor windings are wound on said positive temperature coefficient thermistor and said rotor.
A miniature motor as set forth in claim (1) wherein one set of ends of said rotor windings is connected to said commutator, and another set of ends of said rotor windings is connected to said split poles of said positive-coefficient thermistor.
A miniature motor comprising:
A miniature motor as set forth in claim (6) wherein said positive termperature coefficient thermistor has projections extending in a circumferential direction thereof.
A miniature motor as set forth in claim (6) wherein one set of ends of said rotor windings is connected to said commutator, and other set of ends thereof is connected to said projections.
A miniature motor, comprising:
A miniature motor as set forth in claim (9) wherein said positive temperature coefficient thermistor has projections extending in a circumferential direction thereof.
A miniature motor as set forth in claim (9) wherein said first split poles are connected to said commutator, and said second split poles are connected to said rotor windings which are adjacent to each other.
Dependencies are inferred from the claim text.