US3684934A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Stepping motor drive circuit with path for induced voltages
Assignee: Superior Electric Co
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Filing: 1971-01-11
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Granted: 1972-08-15
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Expires: 1991-01-11
Abstract
Abstract The tendency of a stepping motor having bifilar windings to oscillate or resonate at light loads and relatively high speeds is minimized by a path which initially absorbs most of the energy in the induced voltages and then returns the energy slowly to the power supply. The path also decreases the time which the induced voltage back-biases the power supply and prevents it from energizing the windings for the next step.
Inventors
- 👤 Robert J Loyzim
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 16:21
CPC Classifications
H; H02; H02P; H02P8/00; H02P8/32
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
172 words
In combination with a stepping motor and a motor control circuit therefor in which the stepping motor includes a plurality of poles with each pole having a winding formed into two coils, similar coils of some poles being connected to form at least a first pair of phases with the phases having a common junction, a source of unidirectional power, said motor control circuit being connected to the source and the phases to energize only one phase in the pair simultaneously and to shift the energization in the pair from one phase to the other with the deenergization of one phase causing an induced voltage in the coils of the phase being energized and with the induced voltage being in opposition to the energization, the improvement comprising a lead connected to the common junction of the first pair, a capacitor and path means including diodes, the capacitor and the lead for directing induced voltage currents in the coil to be energized to the capacitor to cause the capacitor to be charged thereby.
Claim 2
Dependent Claim
172 words
In combination with a stepping motor and a motor control circuit therefor in which the stepping motor includes a plurality of poles with each pole having a winding formed into two coils, similar coils of some poles being connected to form at least a first pair of phases with the phases having a common junction, a source of unidirectional power, said motor control circuit being connected to the source and the phases to energize only one phase in the pair simultaneously and to shift the energization in the pair from one phase to the other with the deenergization of one phase causing an induced voltage in the coils of the phase being energized and with the induced voltage being in opposition to the energization, the improvement comprising a lead connected to the common junction of the first pair, a capacitor and path means including diodes, the capacitor and the lead for directing induced voltage currents in the coil to be energized to the capacitor to cause the capacitor to be charged thereby.
Claim 3
Dependent Claim
97 words
The invention as defined in claim 1 in which some of the coils of the remaining poles are connected to form a second pair of phases with said second pair having a common junction, a second lead connected to the second common junction, the path means includes further diodes and the second lead for directing induced voltage currents in the second pair of phases to the capacitor, there are connections from the motor control circuit to the phases and in which the path means includes means for shunting the induced voltages away from the motor control circuit.
Claim 4
Dependent Claim
38 words
The invention as defined in claim 2 in which the capacitor has a value of voltage thereacross and in which the shunt means shunts induced voltages of higher value than said capacitor voltage from the motor control means.
Claim 5
Dependent Claim
60 words
The invention as defined in claim 3 in which each phase has a lead from the motor control circuit, in which the motor control circuit includes a semiconductor means connected to each lead for controlling conduction between the power supply and a lead and in which the shunt means includes a diode connected between each lead and its semiconductor means.
Claim 6
Dependent Claim
48 words
The invention as defined in claim 1 in which the power supply supplies a nominal voltage and in which the capacitor has a size which causes the induced voltage to charge the capacitor to a voltage value only somewhat above the nominal value of the power supply voltage.
Claim 7
Dependent Claim
33 words
The invention as defined in claim 1 in which there are means connected between the capacitor and the power supply means for discharging the capacitor slowly between each occurrence of an induced voltage.
Claim 8
Dependent Claim
38 words
The invention as defined in claim 6 in which the discharge means includes an inductor and in which the discharge means normally maintains the charge across the capacitor at least at the voltage level of the power supply.
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) | 1975-08-15 | 1976-02-14 | 1976-08-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-08-15 | 1980-02-14 | 1980-08-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-08-15 | 1984-02-14 | 1984-08-15 | $7700.00 | Window Closed / Lapsed |