US3815001A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Silicon controlled rectifier motor speed controller
Assignee: LOUIS W PARKER TRUSTEE
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Filing: 1973-03-13
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Granted: 1974-06-04
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Expires: 1993-03-13
Abstract
Abstract An electric motor, for driving an automotive vehicle, has its speed and torque controlled by variable impedance means connected to control the armature current in the motor. The impedance means comprises a plurality of series-connected resistors and silicon controlled rectifiers, connected in a parallel array, with the resistors having different values respectively; and different ones of the rectifiers are rendered conductive to place different values of resistance in series with the motor armature circuit. Commutating capacitors interconnect the anodes of the rectifiers to turn off each rectifier when a next successive rectifier in the array is rendered conductive. The last rectifier in the array has no significant resistance in series therewith; and this rectifier is associated with a further capacitor which is in turn associated with two further silicon controlled rectifiers, one of which is rendered selectively conductive to charge the capacitor at a proper stage of the operation, and the other of which is subsequently rendered conductive to discharge the capacitor when it is desired to turn off the last rectifier in the array.
Inventors
- 👤 J Jamieson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 16:23
CPC Classifications
H; H02; H02P; H02P7/00; H02P7/06; H02P7/18; H02P7/24; H02P7/28; H02P7/285; H02P7/288
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
439 words
An electric motor speed control comprising an electric motor, variable impedance means in series with the armature circuit of said motor for controlling the armature current in said motor thereby to control the speed and torque of said motor, said variable impedance means comprising a plurality of resistors connected in series with a plurality of silicon controlled rectifiers respectively, each of said series connected resistors and rectifiers being connected in series with said armature circuit and in parallel array with one another, said resistors having successively decreasing parameter values respectively from one side to the other of said parallel array with the resistance in series with a last one of said silicon controlled rectifiers in said array having a parameter value of substantially zero, sequentially operable switch means for coupling an energizing signal to the gate electrode of any selected rectifier in said array for rendering said selected rectifier conductive to effectively place the resistance associated with said selected rectifier in series with said armature circuit, a plurality of capacitors connected respectively from the junction of each series connected resistor and rectifier to the junction of a next adjacent one of said series connected resistors and rectifiers in said array whereby each of said capacitors acquires a charge when a particular one of said rectifiers is rendered conductive and is discharged to turn off said particular rectifier when a next adjacent one of said rectifiers is rendered conductive, a further capacitor having one side thereof connected to the junction between said last one of said silicon controlled rectifiers and its substantially zero value series resistance, a further silicon controlled rectifier in series with said further capacitor between the other side of said capacitor and a power source, said switch means including means operable to energize the gate electrode of said further rectifier substantially coincident with the energization of the gate electrode of said last one of said rectifiers in said array to render said further rectifier conductive thereby to charge said further capacitor concurrent with the conduction of said last one of said rectifiers, and a still further silicon controlled recitifer connected between said other side of said further capacitor and the side of said last one of said rectifiers remote from said one side of said further capacitor, said switch means including means operable to energize the gate electrode of said still further electrode coincident with the energization of the gate electrode of a rectifier preceding said last one of said rectifiers in said array to discharge said further capacitor via said still further rectifier thereby to turn off the last one of said rectifiers in said array.
Claim 2
Dependent Claim
439 words
An electric motor speed control comprising an electric motor, variable impedance means in series with the armature circuit of said motor for controlling the armature current in said motor thereby to control the speed and torque of said motor, said variable impedance means comprising a plurality of resistors connected in series with a plurality of silicon controlled rectifiers respectively, each of said series connected resistors and rectifiers being connected in series with said armature circuit and in parallel array with one another, said resistors having successively decreasing parameter values respectively from one side to the other of said parallel array with the resistance in series with a last one of said silicon controlled rectifiers in said array having a parameter value of substantially zero, sequentially operable switch means for coupling an energizing signal to the gate electrode of any selected rectifier in said array for rendering said selected rectifier conductive to effectively place the resistance associated with said selected rectifier in series with said armature circuit, a plurality of capacitors connected respectively from the junction of each series connected resistor and rectifier to the junction of a next adjacent one of said series connected resistors and rectifiers in said array whereby each of said capacitors acquires a charge when a particular one of said rectifiers is rendered conductive and is discharged to turn off said particular rectifier when a next adjacent one of said rectifiers is rendered conductive, a further capacitor having one side thereof connected to the junction between said last one of said silicon controlled rectifiers and its substantially zero value series resistance, a further silicon controlled rectifier in series with said further capacitor between the other side of said capacitor and a power source, said switch means including means operable to energize the gate electrode of said further rectifier substantially coincident with the energization of the gate electrode of said last one of said rectifiers in said array to render said further rectifier conductive thereby to charge said further capacitor concurrent with the conduction of said last one of said rectifiers, and a still further silicon controlled recitifer connected between said other side of said further capacitor and the side of said last one of said rectifiers remote from said one side of said further capacitor, said switch means including means operable to energize the gate electrode of said still further electrode coincident with the energization of the gate electrode of a rectifier preceding said last one of said rectifiers in said array to discharge said further capacitor via said still further rectifier thereby to turn off the last one of said rectifiers in said array.
Claim 3
Dependent Claim
72 words
The combination of claim 1 including a resistance in series with said further silicon controlled rectifier for limiting current flow through said further rectifier during charging of said further capacitor, said still further rectifier being connected directly between said further capacitor and said last one of said rectifiers to produce the highest available current flow to said last one of said rectifiers from said further capacitor upon discharge of said further capacitor.
Claim 4
Dependent Claim
43 words
The combination of claim 1 wherein said plurality of capacitors are connected respectively between the anodes of the silicon controlled rectifiers in said array, said one side of said further capacitor being connected to the anode of said last one of said rectifiers.
Claim 5
Dependent Claim
57 words
The combination of claim 3 wherein the ends of said plurality of resistors remote from said rectifiers in said array are connected together to one side of said armature circuit, the cathodes of the rectifiers in said array being connected together with the cathode of said still further rectifier to the other side of said armature circuit.
Claim 6
Dependent Claim
22 words
The combination of claim 4 including a powEr source between said common cathode connection and the other side of said armature circuit.
Claim 7
Dependent Claim
56 words
The combination of claim 1 wherein said switch means comprises a plurality of contacts connected respectively to the gate electrodes of the rectifiers in said array, a switch arm adapted to engage said contacts in sequence, and a source of pulse voltage coupled to said switch arm for energizing a selected one of said gate electrodes.
Claim 8
Dependent Claim
29 words
The combination of claim 6 wherein said source of pulse voltage comprises a DC power source connected via a parallel combination of resistance and capacitance to said switch arm.
Claim 9
Dependent Claim
37 words
The combination of claim 6 wherein said motor comprises the driving motor of an automotive vehicle, said switch arm being mounted for movement from one to the next of said contacts by a foot-operated vehicle operator''s pedal.
Claim 10
Dependent Claim
123 words
The combination of claim 1 wherein said switch means comprises first and second pluralities of contacts, first and second switch arms ganged to one another and adapted respectively to engage said first and second pluralities of contacts in sequence, said first plurality of contacts being connected to the gate electrodes of the rectifiers in said array, a pulse type voltage souce connected to said first switch arm for selectively energizing the gate electrodes of said rectifiers in said array, at least one of said second plurality of contacts being connected to the gate electrode of said further silicon controlled rectifier, and a further pulse type voltage source connected to said second switch arm for selectively energizing the gate electrode of said further rectifier.
Claim 11
Dependent Claim
28 words
The combination of claim 9 wherein said pulse type voltage sources comprise separate DC power sources connected respectively via RC networks to said first and second switch arms.
Claim 12
Dependent Claim
41 words
The combination of claim 9 wherein the contact which is connected to the gate electrode of the rectifier in said array next preceding said last one of said rectifiers is also connected to the gate electrode of said still further rectifier.
Claim 13
Dependent Claim
51 words
The combination of claim 9 wherein selected adjacent ones of the contacts in said first plurality of contacts are connected to one another to permit said switch arm to move from one to the next of said interconnected contacts without altering the relative states of energization of said silicon controlled rectifiers.
Claim 14
Dependent Claim
280 words
An electric motor speed control comprising an electric motor operative to exhibit a variation in speed in response to a variation in current through a preselected circuit of said motor, a plurality of N current control impedances connected to said motor circuit, said N impedances having parameter values which are respectively scaled from a predetermined maximum value to a predetermined minimum value, a plurality of N silicon controlled rectifiers connected in series with said N impedances respectively, speed control means coupled to the gate electrodes of said N rectifiers for rendering any selected rectifier conductive to effectively couple the impedance in series with the selected rectifier into said motor circuit thereby to control the speed of said motor, a plurality of (N-1) commutating capacitors connected respectively between the anodes of said N rectifiers for turning off any conductive rectifiers, other than the one of said rectifiers in series with said minimum value impedance, when another of said rectifiers is rendered conductive by said speed control means, a further capacitor having one side connected to the anode of said one rectifier and having its other side connected to a controllable charging circuit and to a controllable discharging circuit separate from said charging circuit, means for rendering said charging circuit operative substantially coincident with conduction of said one rectifier to supply a charging current to said further capacitor, said charging circuit being automatically deactivated when said further capacitor has acquired a predetermined charge, and means responsive To subsequent conduction of a selected rectifier other than said one rectifier for rendering said discharging circuit operative to discharge said further capacitor in inverse direction through said one rectifier to turn off said one rectifier.
Claim 15
Dependent Claim
280 words
An electric motor speed control comprising an electric motor operative to exhibit a variation in speed in response to a variation in current through a preselected circuit of said motor, a plurality of N current control impedances connected to said motor circuit, said N impedances having parameter values which are respectively scaled from a predetermined maximum value to a predetermined minimum value, a plurality of N silicon controlled rectifiers connected in series with said N impedances respectively, speed control means coupled to the gate electrodes of said N rectifiers for rendering any selected rectifier conductive to effectively couple the impedance in series with the selected rectifier into said motor circuit thereby to control the speed of said motor, a plurality of (N-1) commutating capacitors connected respectively between the anodes of said N rectifiers for turning off any conductive rectifiers, other than the one of said rectifiers in series with said minimum value impedance, when another of said rectifiers is rendered conductive by said speed control means, a further capacitor having one side connected to the anode of said one rectifier and having its other side connected to a controllable charging circuit and to a controllable discharging circuit separate from said charging circuit, means for rendering said charging circuit operative substantially coincident with conduction of said one rectifier to supply a charging current to said further capacitor, said charging circuit being automatically deactivated when said further capacitor has acquired a predetermined charge, and means responsive To subsequent conduction of a selected rectifier other than said one rectifier for rendering said discharging circuit operative to discharge said further capacitor in inverse direction through said one rectifier to turn off said one rectifier.
Claim 16
Dependent Claim
12 words
The speed control of claim 13 wherein N is at least 4.
Claim 17
Dependent Claim
22 words
The speed control of claim 13 wherein said motor is a DC motor, said motor circuit comprising the armature of said motor.
References Cited (Backward Citations)
US3390318A
Cited
US3628621A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-06-03 | 1977-12-03 | 1978-06-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-06-03 | 1981-12-03 | 1982-06-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-06-03 | 1985-12-03 | 1986-06-04 | $7700.00 | Window Closed / Lapsed |