Patent US3918552A successfully refreshed from Google Patents.
US3918552A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Elevator control system
Assignee: Hitachi Ltd
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Filing: 1974-01-23
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Granted: 1975-11-11
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Expires: 1994-01-23
Abstract
Abstract A system for controlling the braking force applied to an elevator car driven by an A.C. motor in which means for controlling the cut-off position of the elevator car driving motor from the power supply depending on the load of the elevator car are provided so as to ensure accurate arrival of the elevator car at a desired target floor and a comfortable sense of ride under every condition of the load. The elevator control system is advantageous over prior art systems of this kind in that the capacity of the motor can be reduced and a better sense of ride can be obtained.
Inventors
- 👤 Tadao Kameyama
- 👤 Akinori Watanabe
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 17:51
CPC Classifications
B; B66; B66B; B66B1/00; B66B1/34; B66B1/36; B66B1/40
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
167 words
A system for controlling the braking force applied to an elevator car comprising a motor for driving the elevator car, means for detecting the speed of the elevator car, means for detecting the deceleration starting position for the elevator car, circuit breaking means for cutting off said driving motor from the power supply, means for generating a braking pattern signal for applying the braking force to the elevator car in response to the application of the output of said deceleration starting position detecting means, and means for comparing the output of said braking pattern signal generating means with the output of said speed detecting means thereby controlling the braking force applied to the elevator car, wherein means are provided so that the operation of said circuit breaking means and said means applying the braking force to the elevator car can be started with a suitable delay time depending on the load of said motor after the appearance of the output from said deceleration starting position detecting means.
Claim 2
Independent Claim
167 words
A system for controlling the braking force applied to an elevator car comprising a motor for driving the elevator car, means for detecting the speed of the elevator car, means for detecting the deceleration starting position for the elevator car, circuit breaking means for cutting off said driving motor from the power supply, means for generating a braking pattern signal for applying the braking force to the elevator car in response to the application of the output of said deceleration starting position detecting means, and means for comparing the output of said braking pattern signal generating means with the output of said speed detecting means thereby controlling the braking force applied to the elevator car, wherein means are provided so that the operation of said circuit breaking means and said means applying the braking force to the elevator car can be started with a suitable delay time depending on the load of said motor after the appearance of the output from said deceleration starting position detecting means.
Claim 3
Dependent Claim
42 words
A system as claimed in claim 1, wherein said means for delaying the initiation of the operation of said circuit breaking means and said means applying the braking force to the elevator car comprises means for detecting the load of said motor.
Claim 4
Dependent Claim
41 words
A system as claimed in claim 2, further comprising means for reducing the torque generated by said motor, said torque reducing means being adapted to operate in response to the appearance of the output from said deceleration starting position detecting means.
Claim 5
Dependent Claim
87 words
A system as claimed in claim 2, wherein said means including said motor load detecting means for delaying the initiation of the operation of said circuit breaking means and said means applying the braking force to the elevator car comprises a dead zone circuit from which an output appears to actuate said circuit breaking means, when the difference between the output of said elevator car speed detecting means and the output of said braking pattern signal generating means exceeds a predetermined setting of said dead zone circuit.
Claim 6
Dependent Claim
75 words
A system as claimed in claim 2, wherein motor current detecting means for detecting the load of said motor and a dead zone circuit are further provided so that said circuit breaking means can be actuated by the output of said dead zone circuit when the difference between the output of said motor current detecting means and the output of said braking pattern signal generating means exceeds a predetermined setting of said dead zone circuit.
Claim 7
Dependent Claim
42 words
A system as claimed in claim 4, further comprising means for reducing the torque generated by said motor, said motor torque reducing means being adapted to operate in response to the appearance of the output from said deceleration starting position detecting means.
Claim 8
Dependent Claim
42 words
A system as claimed in claim 5, further comprising means for reducing the torque generated by said motor, said motor torque reducing means being adapted to operate in response to the appearance of the output from said deceleration starting position detecting means.
Claim 9
Dependent Claim
96 words
A system as claimed in claim 6, wherein a relay is actuated by the output of said dead zone circuit, and said braking force applying means comprises rectifier means for supplying D.C. braking current to said motor and a phase shifter for controlling said rectifier means, said relay having first contacts disposed between said motor and the power supply and second contacts disposed between said rectifier means and said motor so that said first and second contacts can be opened and closed respectively in response to the appearance of the output from said dead zone circuit.
Claim 10
Dependent Claim
96 words
A system as claimed in claim 7, wherein a relay is actuated by the output of said dead zone circuit, and said braking force applying means comprises rectifier means for supplying D.C. braking current to said motor and a phase shifter for controlling said rectifier means, said relay having first contacts disposed between said motor and the power supply and second contacts disposed between said rectifier means and said motor so that said first and second contacts can be opened and closed respectively in response to the appearance of the output from said dead zone circuit.
Claim 11
Independent Claim
229 words
A system for controlling the braking force applied to an elevator car comprising a motor for driving an elevator car; first means for detecting the speed of the elevator car and issuing a first output signal representative thereof; second means for detecting a deceleration starting position for the elevator car and issuing a second output signal when the elevator car reaches a position distant from a target floor by a predetermined value; circuit breaking means for cutting off power applied to terminals of said motor from a power supply; third means, responsive to said second output signal, for issuing a braking pattern signal representing a predetermined deceleration pattern for the elevator car; fourth means for controlling the braking force applied to the elevator car in response to the difference between said first output signal and said braking pattern signal; and fifth means for delaying by predetermined times depending on the load of said motor the initiation of the operations of said circuit breaking means and said fourth means with respect to the issuance of said second output signal, said fifth means including dead zone circuit means for generating an output permitting said circuit breaking means to be actuated during a period of time when the value of the difference between said first output signal and said braking pattern signal exceeds a predetermined setting of said dead zone circuit means.
Claim 12
Independent Claim
229 words
A system for controlling the braking force applied to an elevator car comprising a motor for driving an elevator car; first means for detecting the speed of the elevator car and issuing a first output signal representative thereof; second means for detecting a deceleration starting position for the elevator car and issuing a second output signal when the elevator car reaches a position distant from a target floor by a predetermined value; circuit breaking means for cutting off power applied to terminals of said motor from a power supply; third means, responsive to said second output signal, for issuing a braking pattern signal representing a predetermined deceleration pattern for the elevator car; fourth means for controlling the braking force applied to the elevator car in response to the difference between said first output signal and said braking pattern signal; and fifth means for delaying by predetermined times depending on the load of said motor the initiation of the operations of said circuit breaking means and said fourth means with respect to the issuance of said second output signal, said fifth means including dead zone circuit means for generating an output permitting said circuit breaking means to be actuated during a period of time when the value of the difference between said first output signal and said braking pattern signal exceeds a predetermined setting of said dead zone circuit means.
Claim 13
Dependent Claim
27 words
A system as claimed in claim 10, further comprising means, responsive to the appearance of said second output signal, for reducing the torque generated by said motor.
Claim 14
Dependent Claim
113 words
A system as claimed in claim 11, wherein said circuit breaking means comprises first relay means disposed between said motor and the power supply, said first relay means having contacts which are opened in response to the concurrence of said second signal and said output of said dead zone circuit means; and said fourth means includes rectifier means for supplying D.C. braking current to said motor, phase shifter means for controlling said rectifier means, and second relay means disposed between said rectifier means and said motor, said second relay means having contacts which are closed in response to the concurrence of said second signal and said output of said dead zone circuit means.
Claim 15
Independent Claim
253 words
A system for controlling the braking force applied to an elevator car comprising; a motor for driving an elevator car; first means for detecting the speed of the elevator car and issuing a first output signal representative thereof; second means for detecting a deceleration starting position for the elevator car and issuing a second output signal when the elevator car reaches a position distant from a target floor by a predetermined value; circuit breaking means for cutting off power applied to terminals of said motor from a power supply; third means, responsive to said second output signal, for issuing a braking pattern signal representing a predetermined deceleration pattern for the elevator car; fourth means for controlling the braking force applied to the elevator car in reponse to the difference between said first output signal and said braking pattern signal; and fifth means for delaying by predetermined times depending on the load of said motor the initIation of the operations of said circuit breaking means and said fourth means with respect to the issuance of said second output signal, said fifth means including sixth means for detecting current of said motor to indicate the load thereof, said sixth means having an output representative thereof, and dead zone circuit means for generating an output permitting said circuit breaking means to be actuated during a period of time when the value of the difference between the output of said sixth means and said braking pattern signal exceeds a predetermined setting of said dead zone circuit means.
Claim 16
Independent Claim
253 words
A system for controlling the braking force applied to an elevator car comprising; a motor for driving an elevator car; first means for detecting the speed of the elevator car and issuing a first output signal representative thereof; second means for detecting a deceleration starting position for the elevator car and issuing a second output signal when the elevator car reaches a position distant from a target floor by a predetermined value; circuit breaking means for cutting off power applied to terminals of said motor from a power supply; third means, responsive to said second output signal, for issuing a braking pattern signal representing a predetermined deceleration pattern for the elevator car; fourth means for controlling the braking force applied to the elevator car in reponse to the difference between said first output signal and said braking pattern signal; and fifth means for delaying by predetermined times depending on the load of said motor the initIation of the operations of said circuit breaking means and said fourth means with respect to the issuance of said second output signal, said fifth means including sixth means for detecting current of said motor to indicate the load thereof, said sixth means having an output representative thereof, and dead zone circuit means for generating an output permitting said circuit breaking means to be actuated during a period of time when the value of the difference between the output of said sixth means and said braking pattern signal exceeds a predetermined setting of said dead zone circuit means.
Claim 17
Dependent Claim
27 words
A system as claimed in claim 13, further comprising means, responsive to the appearance of said second output signal, for reducing the torque generated by said motor.
Claim 18
Dependent Claim
113 words
A system as claimed in claim 14, wherein said circuit breaking means comprises first relay means disposed between said motor and the power supply, said first relay means having contacts which are opened in response to the concurrence of said second signal and said output of said dead zone circuit means; and said fourth means includes rectifier means for supplying D.C. braking current to said motor, phase shifter means for controlling said rectifier means, and second relay means disposed between said rectifier means and said motor, said second relay means having contacts which are closed in response to the concurrence of said second signal and said output of said dead zone circuit means.
References Cited (Backward Citations)
US2403125A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-11-10 | 1979-05-12 | 1979-11-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-11-10 | 1983-05-12 | 1983-11-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-11-10 | 1987-05-12 | 1987-11-11 | $7700.00 | Window Closed / Lapsed |