US4823033A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Miniature motor having coated rubber permanent magnet
Assignee: Mabuchi Motor Co Ltd
•
Filing: 1988-02-26
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Granted: 1989-04-18
•
Expires: 2008-02-26
Abstract
Abstract A miniature motor using a rubber magnet for the permanent magnet for creating a field, in which a coating film is formed on the rubber magnet. The coating film is gas-impermeable, possibly of suitable synthetic resin, to prevent any harmful gas generated in the rubber magnet from escaping therefrom and damaging the contact surfaces of the motor.
Inventors
- 👤 Hitoshi Fujiwara
- 👤 Shotaro Hayakawa
- 👤 Takanobu Lee
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 21:05
CPC Classifications
H; H02; H02K; H02K1/00; H02K1/06; H02K1/12; H02K1/17
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
87 words
A miniature motor of the kind having a coated rubber permanent magnet, the motor having a motor case having rubber magnets on the inside surface and having an opening at one end thereof, a rotor having a commutator on a motor shaft, a small case fitted to said motor case opening, and brushes supported by said small case so as to make electrical contact with said commutator, characterized in that a coating film is formed on the surface of said rubber magnets, said coating film being gas-impermeable.
Claim 2
Dependent Claim
87 words
A miniature motor of the kind having a coated rubber permanent magnet, the motor having a motor case having rubber magnets on the inside surface and having an opening at one end thereof, a rotor having a commutator on a motor shaft, a small case fitted to said motor case opening, and brushes supported by said small case so as to make electrical contact with said commutator, characterized in that a coating film is formed on the surface of said rubber magnets, said coating film being gas-impermeable.
Claim 3
Dependent Claim
24 words
A miniature motor as claimed in claim 1 wherein said coating film is made of a material having resistance to chemicals, oils, and heat.
Claim 4
Dependent Claim
19 words
A miniature motor as claimed in claim 1 wherein said coating film is formed by a synthetic resin layer.
Claim 5
Dependent Claim
28 words
A miniature motor as claimed in claim 1 wherein said coating film is formed by applying a paint or coating solution to the surface of said rubber magnet.
Claim 6
Dependent Claim
28 words
A miniature motor as claimed in claim 1 wherein part of the surface of said rubber magnet is shielded by a casing or structure of said miniature motor.
Claim 7
Dependent Claim
88 words
A miniature electric motor comprising: a motor case; a motor shaft rotatably mounted on the case; a rotor having a commutator and carried by the shaft; brush means mounted on the case so as to make electrical contact with said commutator; at least one rubber permanent magnet mounted within the case on an inside surface thereof; a gas-impermeable film coating provided on the surface of said at least one rubber permanent magnet whereby harmful gases evolving in the rubber magnet are prevented from escaping therefrom into the casing.
Claim 8
Dependent Claim
88 words
A miniature electric motor comprising: a motor case; a motor shaft rotatably mounted on the case; a rotor having a commutator and carried by the shaft; brush means mounted on the case so as to make electrical contact with said commutator; at least one rubber permanent magnet mounted within the case on an inside surface thereof; a gas-impermeable film coating provided on the surface of said at least one rubber permanent magnet whereby harmful gases evolving in the rubber magnet are prevented from escaping therefrom into the casing.
References Cited (Backward Citations)
US3173044A
Cited
US3938914A
Cited
US3818586A
Cited
US3891879A
Cited
US4173822A
Cited
US4482829A
Cited
US4587450A
Cited
US4710659A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-04-17 | 1992-10-17 | 1993-04-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-04-17 | 1996-10-17 | 1997-04-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-04-17 | 2000-10-17 | 2001-04-18 | $7700.00 | Window Closed / Lapsed |