US3619752A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Pulsating current control system for series motors and the like using a controlled rectifier
Assignee: GM Pfaff AG
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Filing: 1969-01-24
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Granted: 1971-11-09
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Expires: 1989-01-24
Abstract
Abstract In a series-wound motor speed control system comprising a solid state controlled rectifier connected in series with the motor and a source of pulsating rectified current, the rectifier is controlled by a synchronized unijunction transistor triggering pulse former including an RC timing network. The time position of the triggering pulses is subject to a threefold control, namely, a manual control, by varying the resistance of the network, to adjust the motor speed, a first automatic control in dependence upon variations of the motor load, and a second automatic control depending upon supply voltage variations, to maintain the adjusted motor speed constant independently of said variations.
Inventors
- 👤 Gediminas Bateika
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 20:54
CPC Classifications
H; H02; H02P; H02P7/00; H02P7/06; H02P7/18; H02P7/24; H02P7/28; H02P7/285; H02P7/292; H02P7/293; Y; Y10; Y10S; Y10S388/00; Y10S388/907; Y10S388/917; Y10S388/919
Claims Analysis
Total Claims: 27
Claim 1
Independent Claim
204 words
A control system for a series-wound electric motor comprising: 1. a solid state controlled rectifier having cathode, anode, and gate electrodes, 2. a source of pulsating voltage, 3. means connecting said source in series with said motor and the anode-cathode path of said rectifier, 4. a unijunction triggering transistor having first base, second base and emitter electrodes, 5. voltage divider means connected to said source including a Zener diode, to provide a first operating voltage varying in accordance with source voltage fluctuations and a second operating voltage stabilized by said diode, 6. means to apply said first operating voltage to the first and second base of said transistor, 7. a resistance-capacitance timing network energized by said second operating voltage and having its common junction connected to said emitter electrode, 8. a triggering transformer having a primary winding connected in the output circuit of said transistor and a secondary winding connected to said gate, 9. means to control the resistance of said network for adjusting the operating speed of said motor, 10. a voltage-responsive variable impedance in effective shunt relation to the capacitance of said network, and 11. means to control said impedance in dependence upon variations of the armature back EMF of said motor.
Claim 2
Dependent Claim
204 words
A control system for a series-wound electric motor comprising: 1. a solid state controlled rectifier having cathode, anode, and gate electrodes, 2. a source of pulsating voltage, 3. means connecting said source in series with said motor and the anode-cathode path of said rectifier, 4. a unijunction triggering transistor having first base, second base and emitter electrodes, 5. voltage divider means connected to said source including a Zener diode, to provide a first operating voltage varying in accordance with source voltage fluctuations and a second operating voltage stabilized by said diode, 6. means to apply said first operating voltage to the first and second base of said transistor, 7. a resistance-capacitance timing network energized by said second operating voltage and having its common junction connected to said emitter electrode, 8. a triggering transformer having a primary winding connected in the output circuit of said transistor and a secondary winding connected to said gate, 9. means to control the resistance of said network for adjusting the operating speed of said motor, 10. a voltage-responsive variable impedance in effective shunt relation to the capacitance of said network, and 11. means to control said impedance in dependence upon variations of the armature back EMF of said motor.
Claim 3
Dependent Claim
5 words
a source of pulsating voltage,
Claim 4
Dependent Claim
5 words
a source of pulsating voltage,
Claim 5
Dependent Claim
31 words
A motor control system as claimed in claim 1, wherein the resistance of said timing network comprises a fixed resistor in series with a variable resistor for controlling the motor speed.
Claim 6
Dependent Claim
22 words
A motor control system as claimed in claim 1, including a trimmer resistor connected in the output circuit of said unijunction transistor.
Claim 7
Dependent Claim
16 words
means connecting said source in series with said motor and the anode-cathode path of said rectifier,
Claim 8
Dependent Claim
16 words
means connecting said source in series with said motor and the anode-cathode path of said rectifier,
Claim 9
Dependent Claim
12 words
a unijunction triggering transistor having first base, second base and emitter electrodes,
Claim 10
Dependent Claim
12 words
a unijunction triggering transistor having first base, second base and emitter electrodes,
Claim 11
Dependent Claim
60 words
A motor control system as claimed in claim 1, wherein said voltage divider means comprises a pair of resistors in series with other and said Zener diode and wherein said first operating voltage is derived from the junction of said fixed resistors and said second operating voltage is derived from the junction of said diode with the adjoining fixed resistor.
Claim 12
Dependent Claim
50 words
A motor control system as claimed in claim 1, wherein said variable impedance consists oF a two-junction transistor having emitter, base and collector electrodes and arranged with its emitter-collector path effectively bypassing the capacitance of said timing network and with its base operably connected to the armature of said motor.
Claim 13
Dependent Claim
33 words
voltage divider means connected to said source including a Zener diode, to provide a first operating voltage varying in accordance with source voltage fluctuations and a second operating voltage stabilized by said diode,
Claim 14
Dependent Claim
33 words
voltage divider means connected to said source including a Zener diode, to provide a first operating voltage varying in accordance with source voltage fluctuations and a second operating voltage stabilized by said diode,
Claim 15
Dependent Claim
16 words
means to apply said first operating voltage to the first and second base of said transistor,
Claim 16
Dependent Claim
16 words
means to apply said first operating voltage to the first and second base of said transistor,
Claim 17
Dependent Claim
31 words
A motor control system as claimed in claim 1, wherein said pulsating current source consists of a rectifier bridge having its coordinated input terminals connected to an alternating current supply network.
Claim 18
Dependent Claim
20 words
a resistance-capacitance timing network energized by said second operating voltage and having its common junction connected to said emitter electrode,
Claim 19
Dependent Claim
20 words
a resistance-capacitance timing network energized by said second operating voltage and having its common junction connected to said emitter electrode,
Claim 20
Dependent Claim
23 words
a triggering transformer having a primary winding connected in the output circuit of said transistor and a secondary winding connected to said gate,
Claim 21
Dependent Claim
23 words
a triggering transformer having a primary winding connected in the output circuit of said transistor and a secondary winding connected to said gate,
Claim 22
Dependent Claim
16 words
means to control the resistance of said network for adjusting the operating speed of said motor,
Claim 23
Dependent Claim
16 words
means to control the resistance of said network for adjusting the operating speed of said motor,
Claim 24
Dependent Claim
15 words
a voltage-responsive variable impedance in effective shunt relation to the capacitance of said network, and
Claim 25
Dependent Claim
15 words
a voltage-responsive variable impedance in effective shunt relation to the capacitance of said network, and
Claim 26
Dependent Claim
17 words
means to control said impedance in dependence upon variations of the armature back EMF of said motor.
Claim 27
Dependent Claim
17 words
means to control said impedance in dependence upon variations of the armature back EMF of said motor.
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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) | 1974-11-08 | 1975-05-10 | 1975-11-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-11-08 | 1979-05-10 | 1979-11-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-11-08 | 1983-05-10 | 1983-11-09 | $7700.00 | Window Closed / Lapsed |