US3708734A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electric motor braking apparatus
Assignee: EIDP Inc
•
Filing: 1972-02-14
•
Granted: 1973-01-02
•
Expires: 1992-02-14
Abstract
Abstract Apparatus for braking an alternating current motor of the induction or synchronous three-phase or single-phase type wherein two power leads are tapped to provide unidirectional braking electric current to a preselected motor winding.
Inventors
- 👤 J Rowe
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 06:43
CPC Classifications
H; H02; H02P; H02P3/00; H02P3/06; H02P3/18; H02P3/24
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
287 words
A braking circuit for an alternating current motor of the induction or synchronous three-phase or single-phase type provided with a switching contactor having a first normally-open contact pair in series connection in the power supply circuit with a preselected drive winding of said motor comprising, in combination, A, for a grounded system, 1. a first silicon-controlled rectifier connected in shunt with respect to said first contact pair through a normally-closed second contact pair of said contactor, 2. a diode connected at one terminal to the return current path of said motor drive winding in opposed polarity sense with respect to said first silicon-controlled rectifier and at the other terminal between said second contact pair and said first silicon-controlled rectifier, 3. a first gating signal supply switch-on means connected in gating circuit relationship with respect to said first silicon-controlled rectifier and in parallel connection therewith to the power supply side of said first contact pair, deriving therefrom potential reference each cycle, closure of said first gating signal supply switch-on means supplying braking unidirectional current through said first siliconcontrolled rectifier to said drive winding, and 4. a first gating signal supply switch-off means terminating supply of said braking unidirectional current to said drive winding after motor standstill, and B, for an ungrounded or Y-grounded system, components (1) to (4), inclusive, of A supra together with 5. a third normally open contact pair of said contactor interposed in series connection in said current return path of said motor drive winding on the motor side of said diode, and 6. a rectifier connected in shunt with respect to said third contact pair in series-consonant forward current direction with respect to said diode, providing a circuit completion path for said drive winding.
Claim 2
Dependent Claim
287 words
A braking circuit for an alternating current motor of the induction or synchronous three-phase or single-phase type provided with a switching contactor having a first normally-open contact pair in series connection in the power supply circuit with a preselected drive winding of said motor comprising, in combination, A, for a grounded system, 1. a first silicon-controlled rectifier connected in shunt with respect to said first contact pair through a normally-closed second contact pair of said contactor, 2. a diode connected at one terminal to the return current path of said motor drive winding in opposed polarity sense with respect to said first silicon-controlled rectifier and at the other terminal between said second contact pair and said first silicon-controlled rectifier, 3. a first gating signal supply switch-on means connected in gating circuit relationship with respect to said first silicon-controlled rectifier and in parallel connection therewith to the power supply side of said first contact pair, deriving therefrom potential reference each cycle, closure of said first gating signal supply switch-on means supplying braking unidirectional current through said first siliconcontrolled rectifier to said drive winding, and 4. a first gating signal supply switch-off means terminating supply of said braking unidirectional current to said drive winding after motor standstill, and B, for an ungrounded or Y-grounded system, components (1) to (4), inclusive, of A supra together with 5. a third normally open contact pair of said contactor interposed in series connection in said current return path of said motor drive winding on the motor side of said diode, and 6. a rectifier connected in shunt with respect to said third contact pair in series-consonant forward current direction with respect to said diode, providing a circuit completion path for said drive winding.
Claim 3
Dependent Claim
42 words
a diode connected at one terminal to the return current path of said motor drive winding in opposed polarity sense with respect to said first silicon-controlled rectifier and at the other terminal between said second contact pair and said first silicon-controlled rectifier,
Claim 4
Dependent Claim
42 words
a diode connected at one terminal to the return current path of said motor drive winding in opposed polarity sense with respect to said first silicon-controlled rectifier and at the other terminal between said second contact pair and said first silicon-controlled rectifier,
Claim 5
Dependent Claim
52 words
A braking circuit for an alternating current motor of tHe induction or synchronous three-phase or single-phase type provided with a switching contactor having a first normally-open contact pair in series connection in the power supply circuit with a preselected drive winding of said motor comprising, in combination, A, for a grounded system,
Claim 6
Dependent Claim
52 words
A braking circuit for an alternating current motor of tHe induction or synchronous three-phase or single-phase type provided with a switching contactor having a first normally-open contact pair in series connection in the power supply circuit with a preselected drive winding of said motor comprising, in combination, A, for a grounded system,
Claim 7
Dependent Claim
42 words
a diode connected at one terminal to the return current path of said motor drive winding in opposed polarity sense with respect to said first silicon-controlled rectifier and at the other terminal between said second contact pair and said first silicon-controlled rectifier,
Claim 8
Dependent Claim
42 words
a diode connected at one terminal to the return current path of said motor drive winding in opposed polarity sense with respect to said first silicon-controlled rectifier and at the other terminal between said second contact pair and said first silicon-controlled rectifier,
Claim 9
Dependent Claim
63 words
a first gating signal supply switch-on means connected in gating circuit relationship with respect to said first silicon-controlled rectifier and in parallel connection therewith to the power supply side of said first contact pair, deriving therefrom potential reference each cycle, closure of said first gating signal supply switch-on means supplying braking unidirectional current through said first silicon-controlled rectifier to said drive winding, and
Claim 10
Dependent Claim
63 words
a first gating signal supply switch-on means connected in gating circuit relationship with respect to said first silicon-controlled rectifier and in parallel connection therewith to the power supply side of said first contact pair, deriving therefrom potential reference each cycle, closure of said first gating signal supply switch-on means supplying braking unidirectional current through said first silicon-controlled rectifier to said drive winding, and
Claim 11
Dependent Claim
63 words
a first gating signal supply switch-on means connected in gating circuit relationship with respect to said first silicon-controlled rectifier and in parallel connection therewith to the power supply side of said first contact pair, deriving therefrom potential reference each cycle, closure of said first gating signal supply switch-on means supplying braking unidirectional current through said first silicon-controlled rectifier to said drive winding, and
Claim 12
Dependent Claim
63 words
a first gating signal supply switch-on means connected in gating circuit relationship with respect to said first silicon-controlled rectifier and in parallel connection therewith to the power supply side of said first contact pair, deriving therefrom potential reference each cycle, closure of said first gating signal supply switch-on means supplying braking unidirectional current through said first silicon-controlled rectifier to said drive winding, and
Claim 13
Dependent Claim
70 words
A braking circuit for an alternating-current motor of the induction or synchronous three-phase or single-phase type according to claim 1 incorporating means fixing the time period in each cycle of the alternating supply current during which said first silicon-controlled rectifier and said rectifier connected in shunt with respect to said third contact pair are actuated to conductive state to thereby effect a preselected application of braking force to said motor.
Claim 14
Dependent Claim
71 words
A braking circuit for an alternating-current motor of the induction or synchronous three-phase or single-phase type according to claim 1 incorporating means fixing voltage amplitude at a preselected level within each cycle of said alternating-current during which first said silicon-controlled rectifier and said rectifier connected in shunt with respect to said third contact pair are actuated to conductive state to thereby effect a preselected application of braking force to said motor.
Claim 15
Dependent Claim
39 words
a first gating signal supply switch-off means terminating supply of said braking unidirectional current to said drive winding after motor standstill, and B, for an ungrounded or Y-grounded system, components (1) to (4), inclusive, of A supra together with
Claim 16
Dependent Claim
39 words
a first gating signal supply switch-off means terminating supply of said braking unidirectional current to said drive winding after motor standstill, and B, for an ungrounded or Y-grounded system, components (1) to (4), inclusive, of A supra together with
Claim 17
Dependent Claim
164 words
a first gating signal supply switch-off means terminating supply of said braking unidirectional current to said drive winding after motor standstill, and B, for an ungrounded or Y-grounded system, components (1) to (4), inclusive, of A supra together with 5 a third normally open contact pair of said contactor interposed in series connection in said current return path of said motor drive winding on the motor side of said diode, 6 a second silicon-controlled rectifier connected in shunt with respect to said third contact pair in series-consonant forward current direction with respect to said diode, and 7 a second gating signal supply switch-on means connected in gating circuit relationship with respect to said second silicon-controlled rectifier and in parallel connection therewith, deriving potential reference each cycle, closure of said second gating signal supply switch-on means providing a circuit completion path for said drive winding in time synchronism with the supply of said braking unidirectional current through said first silicon-controlled rectifier to said drive winding.
Claim 18
Dependent Claim
164 words
a first gating signal supply switch-off means terminating supply of said braking unidirectional current to said drive winding after motor standstill, and B, for an ungrounded or Y-grounded system, components (1) to (4), inclusive, of A supra together with 5 a third normally open contact pair of said contactor interposed in series connection in said current return path of said motor drive winding on the motor side of said diode, 6 a second silicon-controlled rectifier connected in shunt with respect to said third contact pair in series-consonant forward current direction with respect to said diode, and 7 a second gating signal supply switch-on means connected in gating circuit relationship with respect to said second silicon-controlled rectifier and in parallel connection therewith, deriving potential reference each cycle, closure of said second gating signal supply switch-on means providing a circuit completion path for said drive winding in time synchronism with the supply of said braking unidirectional current through said first silicon-controlled rectifier to said drive winding.
Claim 19
Dependent Claim
31 words
a third normally open contact pair of said contactor interposed in series connection in said current return path of said motor drive winding on the motor side of said diode, and
Claim 20
Dependent Claim
31 words
a third normally open contact pair of said contactor interposed in series connection in said current return path of said motor drive winding on the motor side of said diode, and
Claim 21
Dependent Claim
62 words
A braking circuit for an alternating-current motor of the induction or synchronous three-phase or single-phase type according to claim - incorporating means actuating said silicon-controlled rectifier and said first rectifier connected in shunt with respect to said third contact pair to non-conducting state after a preselected elapsed time, thereby limiting the application of unidirectional current to said preselected winding of said motor.
Claim 22
Dependent Claim
31 words
a rectifier connected in shunt with respect to said third contact pair in series-consonant forward current direction with respect to said diode, providing a circuit completion path for said drive winding.
Claim 23
Dependent Claim
31 words
a rectifier connected in shunt with respect to said third contact pair in series-consonant forward current direction with respect to said diode, providing a circuit completion path for said drive winding.
Claim 24
Dependent Claim
40 words
A braking circuit for an alternating current motor of the induction or synchronous three-phase or single-phase type according to claim 1 incorporating means actuating said first silicon-controlled rectifier to non-conductive stAte responsive to sensed zero rotational state of said motor.
Claim 25
Dependent Claim
34 words
A braking circuit for an alternating current motor of the induction or synchronous three-phase or single-phase type according to claim 1 wherein the power supply is of the variable frequency-constant volts per Hertz type.
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) | 1976-01-02 | 1976-07-03 | 1977-01-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-01-02 | 1980-07-03 | 1981-01-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-01-02 | 1984-07-03 | 1985-01-02 | $7700.00 | Window Closed / Lapsed |