US3596154A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrically operated differentially variable dual motor drive system
Assignee: TECH/OPS SEVCON Inc A DE CORP
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Filing: 1969-02-04
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Granted: 1971-07-27
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Expires: 1989-02-04
Abstract
Abstract A drive system with two DC electric motors which are each pulse controlled, a master oscillator for supplying pulses to operate the pulse control of each motor and means for varying, for at least one of the motors, the period in a given time of conduction of that motor so as to render different the mean power supplied to each motor.
Inventors
- 👤 David Gurwicz
- 👤 Albert E Sloan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 19:51
CPC Classifications
H; H02; H02P; H02P7/00; H02P7/06; H02P7/18; H02P7/24; H02P7/28; H02P7/285; H02P7/29; H02P5/00; H02P5/68; Y; Y02; Y02T; Y02T10/00; Y02T10/60; Y02T10/72
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
155 words
An electrically operated, differentially variable drive system in which two DC electric motors are capable of being supplied with different driving power, comprising two electric motors, two semiconductor switching devices for respectively connecting the motors to and disconnecting the motors from electrical supply means, a master electrical oscillator for providing respective output trains of electrical impulses to effect actuation of the switching devices thereby repeatedly to connect each electric motor to and disconnect each electric motor from the electrical supply means, first control means for continuously controlling the output trains of electrical impulses from the master oscillator thereby to vary in like manner the switching of the switching devices so as equally to vary the mean power supplied to each motor, and second control means operable to effect switching of the switching devices so as continuously to vary the mean power supplied to one motor relatively to the mean power supplied to the other motor
Claim 2
Dependent Claim
155 words
An electrically operated, differentially variable drive system in which two DC electric motors are capable of being supplied with different driving power, comprising two electric motors, two semiconductor switching devices for respectively connecting the motors to and disconnecting the motors from electrical supply means, a master electrical oscillator for providing respective output trains of electrical impulses to effect actuation of the switching devices thereby repeatedly to connect each electric motor to and disconnect each electric motor from the electrical supply means, first control means for continuously controlling the output trains of electrical impulses from the master oscillator thereby to vary in like manner the switching of the switching devices so as equally to vary the mean power supplied to each motor, and second control means operable to effect switching of the switching devices so as continuously to vary the mean power supplied to one motor relatively to the mean power supplied to the other motor
Claim 3
Dependent Claim
24 words
A drive system as claimed in claim 1, wherein the semiconductor switching devices comprise respective main thyristors disposed in series with the electric motors.
Claim 4
Dependent Claim
119 words
A drive system as claimed in claim 2, wherein the second control means comprises pulse delay circuits interposed between output connections of the master oscillator and the respective thyristors, means for simultaneously commutating the main thyristors and means for varying the delay of at least one of the delay circuits, the arrangement being such that on varying the delay of one relative to the other of the delay circuits the switching on of one of the main thyristors to connect the motor associated with that thyristor to the supply takes place after the switching on of the other main thyristor so that on simultaneous commutation of the main thyristors one has conducted for a shorter period than the other.
Claim 5
Dependent Claim
48 words
A drive system as claimed in claim 3, wherein a single circuit having a commutating capacitor is employed to effect commutation simultaneously of the main thyristors, the discharge path of the commutating capacitor during commutation including the motors and respective diodes in the freewheel paths of the motors.
Claim 6
Dependent Claim
57 words
A drive system as claimed in claim 3, wherein the master oscillator is adapted to supply a pulse so to operate the means for simultaneously commutating the main thyristors that said commutating means are placed in a condition to enable commutation to take place a predetermined time after the supply of said pulse from the master oscillator.
Claim 7
Dependent Claim
52 words
A drive system as claimed in claim 5, wherein there are provided pulse width regulating means which on the supply of said pulse from the master oscillator to the commutating means are triggered so as, after a predetermined time, to operate the commutating means to effect simultaneous commutation of the main thyristors.
Claim 8
Dependent Claim
41 words
A drive system as claimed in claim 3, wherein the pulse delay circuits incorporate nonlinear circuit means adapted to render a change in the delay effected by either circuit proportional to the change in the element causing said change of delay.
Claim 9
Dependent Claim
60 words
A drive system as claimed in claim 7, wherein the drive system motors comprise the traction motors of a vehicle, the speed of which is controlled by means adapted to control the frequency of the master oscillator and the steering of which is controlled by means adapted to vary the delay effected by at least one of tHe delay circuits.
Claim 10
Dependent Claim
67 words
A drive system as claimed in claim 7, wherein the drive system motors comprise a vehicle traction motor and a further motor and further wherein the frequency of the master oscillator is preset at a fixed maximum value, the speed of each motor being independently controlled by movement of a member which serves to vary the delay effected by the pulse delay circuit associated with the motor.
Claim 11
Dependent Claim
31 words
A drive system as claimed in claim 9, wherein the vehicle traction motor drives one track of a track-laying vehicle and the further motor drives the other track of said vehicle.
Claim 12
Dependent Claim
28 words
A drive system as claimed in claim 10, wherein the vehicle is an industrial truck and the further motor is employed to drive auxiliary services of said truck.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-07-26 | 1975-01-25 | 1975-07-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-07-26 | 1979-01-25 | 1979-07-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-07-26 | 1983-01-25 | 1983-07-27 | $7700.00 | Window Closed / Lapsed |