US3870914A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Current collection means for electric motors
Assignee: Individual
•
Filing: 1973-02-26
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Granted: 1975-03-11
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Expires: 1993-02-26
Abstract
Abstract An electric motor in which the communicating means is controllable and operable individually of the armature of the motor to effect a speed control for the motor. An electric motor the communicating means of which has fixed electric contacts which are an integral multiple of the coils of the motor stator whereby the rate of operation of the commutating means with respect to the rate of operation of the motor is reduced. An electric motor the commutating means of which utilizes a liquid metal to effect an electrical connection between fixed and moving contacts.
Inventors
- 👤 Alan J Walker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 13:00
CPC Classifications
H; H02; H02K; H02K5/00; H02K5/04; H02K5/12; H02K5/128; H02K13/00; H02K13/006; H02K25/00; H02K5/1282
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
222 words
An electric motor comprising a stator having a plurality of induCtive coils for generating a rotating magnetic field, an armature rotatably driven by said magnetic field, commutator means including fixed contacts electrically connected with each inductive coil, rotatable contacts connected to a source of voltage, and rotation means for rotating said rotatable contacts in succession with said fixed contacts whereby said coils of said stator are successively connected to the voltage source: the improvement comprising in that the number of fixed contacts is an integral multiple of the number of coils of said stator; in that each fixed contact comprises an arcuate segment mounted on a common insulating ring; in that each rotatable contact comprises a rotatable brush the polarity of which alternates as it rotates in a circumferential direction; in that said rotation means comprises an auxiliary electric motor having an auxiliary induction rotor mounting said rotatable contacts; in that the stator of the electric motor serves as an auxiliary stator for the auxiliary motor; and, in that the auxiliary induction rotor carries a rotor winding which is electrically connected to the voltage source whereby said auxiliary electric motor uses part of the current supplied to the electric motor such that an increase in current to said rotor winding decreases the rotational speed of the auxiliary rotor and the electric motor.
Claim 2
Dependent Claim
222 words
An electric motor comprising a stator having a plurality of induCtive coils for generating a rotating magnetic field, an armature rotatably driven by said magnetic field, commutator means including fixed contacts electrically connected with each inductive coil, rotatable contacts connected to a source of voltage, and rotation means for rotating said rotatable contacts in succession with said fixed contacts whereby said coils of said stator are successively connected to the voltage source: the improvement comprising in that the number of fixed contacts is an integral multiple of the number of coils of said stator; in that each fixed contact comprises an arcuate segment mounted on a common insulating ring; in that each rotatable contact comprises a rotatable brush the polarity of which alternates as it rotates in a circumferential direction; in that said rotation means comprises an auxiliary electric motor having an auxiliary induction rotor mounting said rotatable contacts; in that the stator of the electric motor serves as an auxiliary stator for the auxiliary motor; and, in that the auxiliary induction rotor carries a rotor winding which is electrically connected to the voltage source whereby said auxiliary electric motor uses part of the current supplied to the electric motor such that an increase in current to said rotor winding decreases the rotational speed of the auxiliary rotor and the electric motor.
Claim 3
Dependent Claim
222 words
An electric motor comprising a stator having a plurality of induCtive coils for generating a rotating magnetic field, an armature rotatably driven by said magnetic field, commutator means including fixed contacts electrically connected with each inductive coil, rotatable contacts connected to a source of voltage, and rotation means for rotating said rotatable contacts in succession with said fixed contacts whereby said coils of said stator are successively connected to the voltage source: the improvement comprising in that the number of fixed contacts is an integral multiple of the number of coils of said stator; in that each fixed contact comprises an arcuate segment mounted on a common insulating ring; in that each rotatable contact comprises a rotatable brush the polarity of which alternates as it rotates in a circumferential direction; in that said rotation means comprises an auxiliary electric motor having an auxiliary induction rotor mounting said rotatable contacts; in that the stator of the electric motor serves as an auxiliary stator for the auxiliary motor; and, in that the auxiliary induction rotor carries a rotor winding which is electrically connected to the voltage source whereby said auxiliary electric motor uses part of the current supplied to the electric motor such that an increase in current to said rotor winding decreases the rotational speed of the auxiliary rotor and the electric motor.
Claim 4
Dependent Claim
222 words
An electric motor comprising a stator having a plurality of induCtive coils for generating a rotating magnetic field, an armature rotatably driven by said magnetic field, commutator means including fixed contacts electrically connected with each inductive coil, rotatable contacts connected to a source of voltage, and rotation means for rotating said rotatable contacts in succession with said fixed contacts whereby said coils of said stator are successively connected to the voltage source: the improvement comprising in that the number of fixed contacts is an integral multiple of the number of coils of said stator; in that each fixed contact comprises an arcuate segment mounted on a common insulating ring; in that each rotatable contact comprises a rotatable brush the polarity of which alternates as it rotates in a circumferential direction; in that said rotation means comprises an auxiliary electric motor having an auxiliary induction rotor mounting said rotatable contacts; in that the stator of the electric motor serves as an auxiliary stator for the auxiliary motor; and, in that the auxiliary induction rotor carries a rotor winding which is electrically connected to the voltage source whereby said auxiliary electric motor uses part of the current supplied to the electric motor such that an increase in current to said rotor winding decreases the rotational speed of the auxiliary rotor and the electric motor.
Claim 5
Dependent Claim
229 words
An electric motor comprising a stator having a plurality of inductive coils for generating a rotating magnetic field, an armature rotatably driven by said magnetic field, commutator means including fixed contacts electrically connected with each inductive coil, rotatable contacts connected to a source of voltage, and rotation means for rotating said rotatable contacts to electrically connect said rotatable contacts in succession with said fixed contacts whereby said coils of said stator are successively connected to the voltage source: the improvement comprising in that the number of fixed contacts is an integral multiple of the number of coils of said stator; in that each fixed contact comprises an arcuate segment mounted on a common insulating ring; in that each rotatable contact comprises a rotatable brush the polarity of which alternates as it rotates in a circumferential direction; in that said rotation means comprises an auxiliary electric motor having an auxiliary induction rotor mounting said rotatable contacts; in that the auxiliary rotor has thereon a ring of high electrical conductivity; and in that a radially moveable magnet is spaced from said ring by which eddy currents are generated in the ring and whereby radial movement of the magnet with respect to the ring will vary the intensity of the eddy currents in the ring to effect a braking force on the rotor and thus vary the rotational speed of the rotor.
Claim 6
Dependent Claim
229 words
An electric motor comprising a stator having a plurality of inductive coils for generating a rotating magnetic field, an armature rotatably driven by said magnetic field, commutator means including fixed contacts electrically connected with each inductive coil, rotatable contacts connected to a source of voltage, and rotation means for rotating said rotatable contacts to electrically connect said rotatable contacts in succession with said fixed contacts whereby said coils of said stator are successively connected to the voltage source: the improvement comprising in that the number of fixed contacts is an integral multiple of the number of coils of said stator; in that each fixed contact comprises an arcuate segment mounted on a common insulating ring; in that each rotatable contact comprises a rotatable brush the polarity of which alternates as it rotates in a circumferential direction; in that said rotation means comprises an auxiliary electric motor having an auxiliary induction rotor mounting said rotatable contacts; in that the auxiliary rotor has thereon a ring of high electrical conductivity; and in that a radially moveable magnet is spaced from said ring by which eddy currents are generated in the ring and whereby radial movement of the magnet with respect to the ring will vary the intensity of the eddy currents in the ring to effect a braking force on the rotor and thus vary the rotational speed of the rotor.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-03-10 | 1978-09-09 | 1979-03-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-03-10 | 1982-09-09 | 1983-03-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-03-10 | 1986-09-09 | 1987-03-11 | $7700.00 | Window Closed / Lapsed |