US3701935A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Circuit for food mixer
Assignee: Kenwood Manufacturing Woking Ltd
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Filing: 1971-06-23
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Granted: 1972-10-31
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Expires: 1991-06-23
Abstract
Abstract An alternating current electric motor speed control circuit including a bi-directional semiconductor control element in the motor circuit triggered from a blocking to a conductive state by the application of a potential to its control electrode applied through governor contacts of a motor speed governor contacts, which contacts are closed when the motor speed drops below a particular value which can be varied and which carry a small proportion of the total motor current.
Inventors
- 👤 Arthur A Collie
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 13:13
CPC Classifications
H; H02; H02P; H02P25/00; H02P25/16; H02P25/18; H02P25/182; Y; Y10; Y10S; Y10S388/00; Y10S388/907; Y10S388/917; Y10S388/923; Y10S388/924; Y10S388/926
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
153 words
In an alternating current electric motor control circuit comprising, in combination: a. an alternating current electric motor including an armature and first and second field windings coupled in series one on each side of said armature, b. an alternating current motor supply circuit coupled to said first and second field windings, and c. a motor speed governor having a pair of contacts separable in response to the speed of said motor exceeding a given value, the improvement comprising: d. a bi-directional triode thyristor coupled in series between said first field winding and said armature, said thyristor having a control electrode coupled to one of said pair of contacts, e. an electrical resistive element and a capacitive reactive element connected in series with each other and in parallel with said thyristor, and f. the other of said pair of contacts being coupled to the conductive path between said first field winding and said thyristor.
Claim 2
Dependent Claim
153 words
In an alternating current electric motor control circuit comprising, in combination: a. an alternating current electric motor including an armature and first and second field windings coupled in series one on each side of said armature, b. an alternating current motor supply circuit coupled to said first and second field windings, and c. a motor speed governor having a pair of contacts separable in response to the speed of said motor exceeding a given value, the improvement comprising: d. a bi-directional triode thyristor coupled in series between said first field winding and said armature, said thyristor having a control electrode coupled to one of said pair of contacts, e. an electrical resistive element and a capacitive reactive element connected in series with each other and in parallel with said thyristor, and f. the other of said pair of contacts being coupled to the conductive path between said first field winding and said thyristor.
Claim 3
Dependent Claim
33 words
An electric motor control circuit as defined in claim 1, in which said other of said pair of contacts is connected to a junction of said resistive element and said capacitive reactive element.
Claim 4
Dependent Claim
35 words
An electric motor control circuit as defined in claim 1, further comprising fiRst and second interference suppression chokes coupled in series with said first and second field windings, respectively, and said electric motor supply circuit.
Claim 5
Dependent Claim
230 words
In an alternating current electric motor control circuit comprising, in combination: a. an alternating current electric motor including an armature and first and second field windings coupled in series one on each side of said armature, b. an alternating current motor supply circuit coupled to said first and second field windings, and c. a motor speed governor having a pair of contacts separable in response to the speed of said motor exceeding a given value, the improvement comprising: d. a bi-directional triode thyristor coupled in series between said first field winding and said armature, said thyristor having a control electrode coupled to one of said pair of contacts, e. an electrical resistive element and a capacitive reactive element connected in series with each other and in parallel with said thyristor, f. a further resistive element connected in series between said one of said pair of contacts and said control electrode, g. the other of said pair of contacts being coupled in the conductive path between said first field winding and said thyristor, h. two interference suppression choke means, coupled in series in said electric motor supply circuit, one on each side of said motor, i. capacitor means connected in parallel with said motor and in series with said choke means; and j. switch means in that part of said motor supply circuit which is in parallel with said capacitor means.
Claim 6
Dependent Claim
230 words
In an alternating current electric motor control circuit comprising, in combination: a. an alternating current electric motor including an armature and first and second field windings coupled in series one on each side of said armature, b. an alternating current motor supply circuit coupled to said first and second field windings, and c. a motor speed governor having a pair of contacts separable in response to the speed of said motor exceeding a given value, the improvement comprising: d. a bi-directional triode thyristor coupled in series between said first field winding and said armature, said thyristor having a control electrode coupled to one of said pair of contacts, e. an electrical resistive element and a capacitive reactive element connected in series with each other and in parallel with said thyristor, f. a further resistive element connected in series between said one of said pair of contacts and said control electrode, g. the other of said pair of contacts being coupled in the conductive path between said first field winding and said thyristor, h. two interference suppression choke means, coupled in series in said electric motor supply circuit, one on each side of said motor, i. capacitor means connected in parallel with said motor and in series with said choke means; and j. switch means in that part of said motor supply circuit which is in parallel with said capacitor means.
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) | 1975-10-31 | 1976-05-01 | 1976-10-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-10-31 | 1980-05-01 | 1980-10-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-10-31 | 1984-05-01 | 1984-10-31 | $7700.00 | Window Closed / Lapsed |