Patent US3876918A successfully refreshed from Google Patents.
US3876918A
Expired / Lapsed
US
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Electric motor controlling system
Assignee: Hitachi Ltd
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Filing: 1973-08-09
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Granted: 1975-04-08
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Expires: 1993-08-09
Abstract
Abstract An electric motor controlling system comprising an induction motor system consisting of at least one induction motor having motoring torque generating means and braking torque generating means, antiparallel connection of thyristors connected between an Ac source and the motoring torque generating means, means for controlling the thyristors such that the motoring torque generating means generates, when the speed deviation is positive, a motoring torque corresponding to the value of the speed deviation, a controllable rectifying circuit connected between the AC source and the braking torque generating means, means for controlling the controllable rectifying circuit such that the breaking torque generating means generates, when the speed deviation is negative, a braking torque corresponding to the value of the speed deviation, and means for giving the torques of the motor system a push-pull characteristic depending upon the speed deviation by biassing the two control means.
Inventors
- 👤 Katsu Komuro
- 👤 Nobuo Mitsui
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 19:02
CPC Classifications
H; H02; H02P; H02P5/00; H02P5/74; H02P5/747; B; B66; B66B; B66B1/00; B66B1/24; B66B1/28; B66B1/285; B66B1/30; B66B1/308
Claims Analysis
Total Claims: 26
Claim 1
Independent Claim
146 words
An electric motor controlling system comprising: an electric motor system consisting of at least one electric motor having a first means for generating a motoring torque and a second means for generating a braking torque; means for generating a torque control instruction; means for causing said first means to generate, when the output of said torque control instruction generating means is positive, a motoring torque corresponding to the value of said output; means for causing said second means to generate, when the output of said torque control instruction generating means is negative, a braking torque corresponding to the value of the latter output; and means acting on said means for causing to generate the motoring torque and said means for causing to generate the braking torque for giving the torques obtained by said first and second means a push-pull characteristic depending upon said torque control instruction.
Claim 2
Dependent Claim
146 words
An electric motor controlling system comprising: an electric motor system consisting of at least one electric motor having a first means for generating a motoring torque and a second means for generating a braking torque; means for generating a torque control instruction; means for causing said first means to generate, when the output of said torque control instruction generating means is positive, a motoring torque corresponding to the value of said output; means for causing said second means to generate, when the output of said torque control instruction generating means is negative, a braking torque corresponding to the value of the latter output; and means acting on said means for causing to generate the motoring torque and said means for causing to generate the braking torque for giving the torques obtained by said first and second means a push-pull characteristic depending upon said torque control instruction.
Claim 3
Dependent Claim
59 words
An electric motor controlling system according to claim 1, further comprising: means for detecting an electrical quantity relating to the produced torque of at least one of said first and second means; and means for negatively feeding the output of said detecting means back to said torque generation causing means for the other of said first and second means.
Claim 4
Dependent Claim
34 words
An electric motor controlling system according to claim 2, wherein said torque generation causing means receiving the negatively fed back output of said detecting means is responsive thereto for reducing the torque generated thereby.
Claim 5
Dependent Claim
35 words
An electric motor controlling system according to claim 1, in which said electric motor system comprises a first and a second electric motor interconnected with each other serving respectively as said first and second means.
Claim 6
Dependent Claim
41 words
An electric motor controlling system according to claim 4, in which said first electric motor comprises an induction motor, and said motoring torque generation causing means comprises an AC source and thyristors connected between said AC source and said induction motor.
Claim 7
Dependent Claim
44 words
An electric motor controlling system according to claim 4, in which said second electric motor comprises an induction motor, and said braking torque generation causing means comprises an AC source and a controllable rectifying circuit connected between said AC source and said induction motor.
Claim 8
Dependent Claim
48 words
An electric motor controlling system according to claim 6, in which said rectifying circuit comprises: a pair of thyristors connected in series on opposite sides of one AC side terminal; and a pair of unidirectional elements connected in series on opposite sides of the other AC side terminal.
Claim 9
Dependent Claim
35 words
An electric motor controlling system according to claim 1, in which said electric motor system comprises one electric motor having a first winding and a second winding serving respectively as said first and second means.
Claim 10
Dependent Claim
40 words
An electric motor controlling system according to claim 8, in which said electric motor comprises an induction motor, and said motoring torque generation causing means comprises an AC source and thyristors connected between said AC source and said first winding.
Claim 11
Dependent Claim
43 words
An electric motor controlling system according to claim 8, in which said electric motor comprises an induction motor, and said braking torque generation causing means comprises an AC source and a controllable rectifying circuit connected between said AC source and said second winding.
Claim 12
Dependent Claim
48 words
An electric motor controlling system according to claim 10, in which said rectifying circuit comprises: a pair of thyristors connected in series on opposite sides of one AC side terminal; and a pair of unidirectional elements connected in series on opposite sides of the other AC side terminal
Claim 13
Dependent Claim
31 words
An electric motor controlling system according to claim 1, wherein said means for giving a push-pull characteristic enable the simultaneous generation of both motoring and braking torques in a predetermined range.
Claim 14
Dependent Claim
167 words
An electric motor controlling system comprising: an electric motor system consisting of at least one electric motor having a first means for generating a motoring torque and a second means for generating a braking torque; a pattern generator for generating a speed instruction; means for detecting the speed of said electric motor; a comparator for comparing the output of said pattern generator with the output of said speed detecting means; means for causing said first means to generate, when the output of said comparator is positive, a motoring torque corresponding to the value of said output; means for causing said second means to generate, when the output of said comparator is negative, a braking torque corresponding to the value of the latter output; and means acting on said means for causing to generate the motoring torque and said means for causing to generate the braking torque for giving the torques obtained by said first and second means a push-pull characteristic depending upon the output of said comparator.
Claim 15
Dependent Claim
167 words
An electric motor controlling system comprising: an electric motor system consisting of at least one electric motor having a first means for generating a motoring torque and a second means for generating a braking torque; a pattern generator for generating a speed instruction; means for detecting the speed of said electric motor; a comparator for comparing the output of said pattern generator with the output of said speed detecting means; means for causing said first means to generate, when the output of said comparator is positive, a motoring torque corresponding to the value of said output; means for causing said second means to generate, when the output of said comparator is negative, a braking torque corresponding to the value of the latter output; and means acting on said means for causing to generate the motoring torque and said means for causing to generate the braking torque for giving the torques obtained by said first and second means a push-pull characteristic depending upon the output of said comparator.
Claim 16
Dependent Claim
74 words
An electric motor controlling system according to claim 13, in which said pattern generator comprises: an acceleration pattern generator for generating a speed instruction increasing with time; a deceleration pattern ggenerator for generating an output decreasing as a function of the position of a load coupled to said electric motor; and means for preferentially outputting a lower one of the supplied output of said acceleration pattern generator and output of said deceleration pattern generator.
Claim 17
Dependent Claim
39 words
An electric motor controlling system according to claim 13, in which said push-pull characteristic giving means comprises means for applying bias to at least one of said motoring torque generation causing means and said braking torque generation causing means.
Claim 18
Dependent Claim
35 words
An electric motor controlling system according to claim 13, in which said electric motor system comprises a first and a second electric motors interconnected with each other serving respectively as said first and second means.
Claim 19
Dependent Claim
35 words
An electric motor controlling system according to claim 13, in which said electric motor system comprises one electric motor having a first winding and a second winding serving respectively as said first and second means.
Claim 20
Dependent Claim
31 words
An electric motor controlling system according to claim 13, wherein said means for giving a push-pull characteristic enable the simultaneous generation for both motoring and braking torques in a predetermined range.
Claim 21
Dependent Claim
162 words
An electric motor controlling system comprising: a pair of induction motors having different numbers of poles and interconnected with each other; a pattern generator for generating a speed instruction; means for detecting the speed of said induction motor; a comparator for comparing the output of said pattern generator with the output of said speed detecting means; means for causing said induction motor with a lower number of poles to generate, when the output of said comparator is positive, a motoring torque corresponding to the value of said output; means for causing said induction motor with a higher number of poles to generate, when the output of said comparator is negative, a braking torque corresponding to the value of the latter output; and means acting on said means for causing to generate the motoring torque and said means for causing to generate the braking torque for giving the torques of both said motors a push-pull characteristic depending upon the output of said comparator.
Claim 22
Dependent Claim
162 words
An electric motor controlling system comprising: a pair of induction motors having different numbers of poles and interconnected with each other; a pattern generator for generating a speed instruction; means for detecting the speed of said induction motor; a comparator for comparing the output of said pattern generator with the output of said speed detecting means; means for causing said induction motor with a lower number of poles to generate, when the output of said comparator is positive, a motoring torque corresponding to the value of said output; means for causing said induction motor with a higher number of poles to generate, when the output of said comparator is negative, a braking torque corresponding to the value of the latter output; and means acting on said means for causing to generate the motoring torque and said means for causing to generate the braking torque for giving the torques of both said motors a push-pull characteristic depending upon the output of said comparator.
Claim 23
Dependent Claim
31 words
An electric motor controlling system according to claim 19, wherein said means for giving a push-pull characteristic enable the simultaneous generation of both motoring and braking torques in a predetermined range.
Claim 24
Dependent Claim
195 words
An electric motor controlling system comprising: a pair of induction motors having different numbers of poles and interconnected with each other; a pattern generator for generating a speed instruction; means for detecting the speed of said induction motor; a comparator for comparing the output of said pattern generator with the output of said speed detecting means; means including an AC source and thyristors connected between said AC source and said induction motor with a lower number of poles for causing said induction motor to generate, when the output of said comparator is positive, a motoring torque corresponding to the value of said output; means including an AC source and a controllable rectifying circuit connected between said AC source and said induction motor with a higher number of poles for causing the latter induction motor to generate, when the output of said comparator is negative, a braking torque corresponding to the value of the latter output; and means acting on said means for causing to generate the motoring torque and means for causing to generate the braking torque for giving the torques of both said motors a push-pull characteristic depending upon the output of said comparator.
Claim 25
Dependent Claim
195 words
An electric motor controlling system comprising: a pair of induction motors having different numbers of poles and interconnected with each other; a pattern generator for generating a speed instruction; means for detecting the speed of said induction motor; a comparator for comparing the output of said pattern generator with the output of said speed detecting means; means including an AC source and thyristors connected between said AC source and said induction motor with a lower number of poles for causing said induction motor to generate, when the output of said comparator is positive, a motoring torque corresponding to the value of said output; means including an AC source and a controllable rectifying circuit connected between said AC source and said induction motor with a higher number of poles for causing the latter induction motor to generate, when the output of said comparator is negative, a braking torque corresponding to the value of the latter output; and means acting on said means for causing to generate the motoring torque and means for causing to generate the braking torque for giving the torques of both said motors a push-pull characteristic depending upon the output of said comparator.
Claim 26
Dependent Claim
31 words
An electric motor controlling system according to claim 21, wherein said means for giving a push-pull characteristic enable the simultaneous generation of both motoring and braking torques in a predetermined range.
References Cited (Backward Citations)
US3678355A
Cited
US3767987A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-04-07 | 1978-10-07 | 1979-04-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-04-07 | 1982-10-07 | 1983-04-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-04-07 | 1986-10-07 | 1987-04-08 | $7700.00 | Window Closed / Lapsed |