Patent US3821628A successfully refreshed from Google Patents.
US3821628A
Expired / Lapsed
US
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Elevator system
Assignee: Westinghouse Electric Corp
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Filing: 1973-05-21
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Granted: 1974-06-28
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Expires: 1993-05-21
Abstract
Abstract An elevator system including an elevator car mounted for movement in a guided path, and means including static converter apparatus connected to a source of alternating potential and to a direct current motor, for driving the elevator car in its guided path. The static converter apparatus includes an electrical filter on the direct current side thereof for reducing the magnitude of the ripple component in the direct current voltage applied to the direct current motor, to reduce the operating sound level thereof.
Inventors
- 👤 W Caputo
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 11:00
CPC Classifications
H; H02; H02M; H02M1/00; H02M1/12; B; B66; B66B; B66B1/00; B66B1/24; B66B1/28; B66B1/30; H02M7/00; H02M7/02; H02M7/04; H02M7/12; H02M7/145; H02M7/155; H02M7/162
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
146 words
An elevator system, comprising: an elevator car mounted for movement in a guided path, means including a direct current motor having an armature, for driving said elevator car in its guided path, a static converter for providing a direct current voltage for the armature of said direct current drive motor, said static converter including an alternating current circuit, a first direct current circuit connected to said alternating current circuit, said first direct current circuit providing a direct current output voltage having a ripple component therein, and a low-pass damped L-C filter circuit interconnecting said first direct current circuit and the armature of said direct current motor to provide a direct current through the armature in a first direction, said filter circuit being tuned to a frequency less than the fundamental frequency of the ripple component to reduce the operating sound level of the direct current motor.
Claim 2
Dependent Claim
146 words
An elevator system, comprising: an elevator car mounted for movement in a guided path, means including a direct current motor having an armature, for driving said elevator car in its guided path, a static converter for providing a direct current voltage for the armature of said direct current drive motor, said static converter including an alternating current circuit, a first direct current circuit connected to said alternating current circuit, said first direct current circuit providing a direct current output voltage having a ripple component therein, and a low-pass damped L-C filter circuit interconnecting said first direct current circuit and the armature of said direct current motor to provide a direct current through the armature in a first direction, said filter circuit being tuned to a frequency less than the fundamental frequency of the ripple component to reduce the operating sound level of the direct current motor.
Claim 3
Dependent Claim
43 words
The elevator system of claim 1 wherein the filter circuit includes inductance means connected between the first direct current circuit and the armature of the direct current motor, and resistance and capacitance means serially connected across the armature of the direct current motor.
Claim 4
Dependent Claim
20 words
The elevator system of claim 2 wherein the filter circuit includes a fuse connected in series with the capacitance means.
Claim 5
Dependent Claim
29 words
The elevator system of claim 3 wherein the filter circuit includes means connected to discharge the capacitance means when the fuse opens the circuit which includes the capacitance means.
Claim 6
Dependent Claim
36 words
The elevator system of claim 1 wherein the ripple component has a frequency of 360 hertz and the damped low-pass L-C filter is tuned to a frequency in the range of about 100 to 180 hertz.
Claim 7
Dependent Claim
93 words
The elevator system of claim 1 including a second direct current circuit connected in anti-parallel with the first direct current circuit, said second direct current circuit providing a direct current output voltage having a ripple component therein, said second direct current circuit providing a direct current through the armature in a direction opposite to the first direction, said filter circuit reducing the magnitude of the ripple component applied to the armature of the direct current motor by said second direct current circuit, and means selectively operating said first and second direct current circuits.
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) | 1977-06-27 | 1977-12-27 | 1978-06-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-06-27 | 1981-12-27 | 1982-06-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-06-27 | 1985-12-27 | 1986-06-28 | $7700.00 | Window Closed / Lapsed |