Patent US3662238A successfully refreshed from Google Patents.
US3662238A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electronically commutated motor
Assignee: Panasonic Holdings Corp
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Filing: 1969-05-20
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Granted: 1972-05-09
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Expires: 1989-05-20
Abstract
Abstract An electronically commutated motor and control means therefor. The electronically commutated motor has no dead zone and no overlap despite an imperfect position detecting signal. The transition of the commutation is carried out in a differential manner. Any fluctuation in the operating temperature and/or deviation of the supply voltage does not disturb the commutation. The generating torque of the motor is easily controlled by a small power without using any additional power control means. A constant torque motor and a constant speed motor are illustrated.
Inventors
- 👤 Kazutsugu Kobayashi
- 👤 Hisayuki Matsumoto
- 👤 Yoshiaki Igarashi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 22:46
CPC Classifications
H; H02; H02K; H02K29/00; H02K29/06; H02K29/12
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
260 words
An electric motor apparatus comprising stator windings mounted for generating magnetic fields in selected areas; a permanently magnetized rotor movably mounted adjacent said stator windings for rotation within said magnetic fields; a position detecting means coupled to said rotor for detecting the relative rotational position of said stator windings and said rotor, said position detecting means including voltage generating means for generating a family of voltages having values varying according to said rotational position; a current control circuit comprising a control terminal and a current path; a plurality of transistors, the emitter of each of said transistors being coupled to the current path of said current control circuit; means for generating a pedestal voltage to which said voltage generating means is coupled for adding said pedestal voltage to each of said family of voltages, the output of said pedestal voltage generating means being coupled with the bases of said transistors and the current path of said current control circuit for supplying the voltage generated by said position detecting means across the bases of said transistors and the current path of said current control circuit; means coupling the collectors of said transistors to the respective stator windings; means for detecting the rotational speed of said rotor generating a signal corresponding to the speed; means for generating a reference signal to provide a signal corresponding to the predetermined speed; and means for comparing said signal corresponding to the speed and said reference signal and obtaining a signal to control said control circuit and coupled to said terminal of said current control circuit.
Claim 2
Dependent Claim
260 words
An electric motor apparatus comprising stator windings mounted for generating magnetic fields in selected areas; a permanently magnetized rotor movably mounted adjacent said stator windings for rotation within said magnetic fields; a position detecting means coupled to said rotor for detecting the relative rotational position of said stator windings and said rotor, said position detecting means including voltage generating means for generating a family of voltages having values varying according to said rotational position; a current control circuit comprising a control terminal and a current path; a plurality of transistors, the emitter of each of said transistors being coupled to the current path of said current control circuit; means for generating a pedestal voltage to which said voltage generating means is coupled for adding said pedestal voltage to each of said family of voltages, the output of said pedestal voltage generating means being coupled with the bases of said transistors and the current path of said current control circuit for supplying the voltage generated by said position detecting means across the bases of said transistors and the current path of said current control circuit; means coupling the collectors of said transistors to the respective stator windings; means for detecting the rotational speed of said rotor generating a signal corresponding to the speed; means for generating a reference signal to provide a signal corresponding to the predetermined speed; and means for comparing said signal corresponding to the speed and said reference signal and obtaining a signal to control said control circuit and coupled to said terminal of said current control circuit.
Claim 3
Dependent Claim
237 words
An electric motor apparatus comprising: three sets of stator windings mounted for generating magnetic fields in selected areas; a permanently magnetized rotor movably mounted adjacent said stator windings for rotation within said magnetic fields; a position detecting means having a position detecting rotor coupled with said permanently magnetized rotor and rotatable therewith, and position detecting stator means positioned around said position detecting rotor, said position detecting stator means generating three sets of gradually varying position signals in cooperation with the position detecting rotor during rotation thereof, said position signal indicating the relation of the relative rotational position of said stator windings and said rotor and being gradually varying signals which have a poor on-off ratio; a pedestal voltage generating means to which said position detecting means is coupled for providing a direct current bias voltage to the position signals; an impedance means having two terminals and the impedance of which is variable in response to an external command; three transistors, the emitter of each of said transistors being coupled to one terminal of said impedance means, said position detecting Means being coupled to the bases of said transistors and to the pedestal voltage generating means for supplying the signals generated by said position detecting means and the pedestal voltage means across the bases of said transistors and the other terminal of said impedance means; and means coupling the collectors of said transistors to the respective stator windings.
Claim 4
Dependent Claim
237 words
An electric motor apparatus comprising: three sets of stator windings mounted for generating magnetic fields in selected areas; a permanently magnetized rotor movably mounted adjacent said stator windings for rotation within said magnetic fields; a position detecting means having a position detecting rotor coupled with said permanently magnetized rotor and rotatable therewith, and position detecting stator means positioned around said position detecting rotor, said position detecting stator means generating three sets of gradually varying position signals in cooperation with the position detecting rotor during rotation thereof, said position signal indicating the relation of the relative rotational position of said stator windings and said rotor and being gradually varying signals which have a poor on-off ratio; a pedestal voltage generating means to which said position detecting means is coupled for providing a direct current bias voltage to the position signals; an impedance means having two terminals and the impedance of which is variable in response to an external command; three transistors, the emitter of each of said transistors being coupled to one terminal of said impedance means, said position detecting Means being coupled to the bases of said transistors and to the pedestal voltage generating means for supplying the signals generated by said position detecting means and the pedestal voltage means across the bases of said transistors and the other terminal of said impedance means; and means coupling the collectors of said transistors to the respective stator windings.
Claim 5
Dependent Claim
18 words
An electric motor apparatus as claimed in claim 2, in which said impedance means is a variable resistor.
Claim 6
Dependent Claim
24 words
An electric motor apparatus as claimed in claim 2, in which said impedance means is a variable impedance means responsive to a physical value.
Claim 7
Dependent Claim
20 words
An electric motor apparatus as claimed in claim 2, in which said impedance means is a resistor and a transistor.
References Cited (Backward Citations)
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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) | 1975-05-09 | 1975-11-08 | 1976-05-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-05-09 | 1979-11-08 | 1980-05-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-05-09 | 1983-11-08 | 1984-05-09 | $7700.00 | Window Closed / Lapsed |