US3590355A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Digital positioning motor control for an elevator
Assignee: Individual
•
Filing: 1969-10-22
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Granted: 1971-06-29
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Expires: 1989-10-22
Abstract
Abstract An elevator control system having an encoder connected to the elevator cable drum shaft that provides output signals indicating the exact position of elevator travel. The output of the encoder is sensed by a plurality of comparators which provide output signal at top and bottom maximum travel positions and various intermediate positions. At a predetermined distance on both sides of these positions, the comparators provide signals to slow down the elevator. Speed control logic employing the encoder, flipflops and a comparator is also employed.
Inventors
- 👤 Lanny L Davis
- 👤 Wilmer G Radke
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 12:52
CPC Classifications
B; B66; B66B; B66B1/00; B66B1/34; B66B1/3492; B66B1/02; B66B1/06; B66B1/14; B66B1/16; G; G05; G05B; G05B19/00; G05B19/02; G05B19/18; G05B19/19; G05B19/27; G05B19/29; G05B19/291
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
218 words
A control system comprising: a. an encoder; b. first, second, third and fourth comparators; c. the output of said encoder being operatively connected to the inputs of said first, second, third and fourth encoders; d. said first and second comparators respectively providing emergency stop signals at positions of maximum and minimum travel of said encoder; e. said third comparator providing a stop signal at at least one predetermined stop position between said positions of maximum and minimum travel, f. said fourth comparator providing a slow signal at predetermined positions on each side of said predetermined stop position; g. the outputs of said first and second comparators are connected to the inputs of first and second gates; h. the output of said first gate being operatively connected to the high speed section of a two-speed motor; i. the output of said second gate being operatively connected to the low speed section of said two-speed motor; j. the output of said third comparator is applied through a first switch to the inputs of said first and second gates; and k. the output of said fourth comparator is applied through a second switch to the input of said first gate and to the input of an inverter, the output of said inverter being connected to the input of said second gate.
Claim 2
Dependent Claim
218 words
A control system comprising: a. an encoder; b. first, second, third and fourth comparators; c. the output of said encoder being operatively connected to the inputs of said first, second, third and fourth encoders; d. said first and second comparators respectively providing emergency stop signals at positions of maximum and minimum travel of said encoder; e. said third comparator providing a stop signal at at least one predetermined stop position between said positions of maximum and minimum travel, f. said fourth comparator providing a slow signal at predetermined positions on each side of said predetermined stop position; g. the outputs of said first and second comparators are connected to the inputs of first and second gates; h. the output of said first gate being operatively connected to the high speed section of a two-speed motor; i. the output of said second gate being operatively connected to the low speed section of said two-speed motor; j. the output of said third comparator is applied through a first switch to the inputs of said first and second gates; and k. the output of said fourth comparator is applied through a second switch to the input of said first gate and to the input of an inverter, the output of said inverter being connected to the input of said second gate.
Claim 3
Dependent Claim
91 words
The device of claim 1 including: a. a speed control means for an electric motor; b. said speed control means including a pulse counting device the input of which is connected to the output of said encoder; c. a speed comparator having one input connected to the output of said pulse counting device and another input connected to a clock; and d. said speed comparator providing an output signal when the pulse count of said pulse counting device exceeds a predetermined amount during a predetermined time as set by said clock.
Claim 4
Dependent Claim
48 words
The device of claim 2 wherein: a. said pulse counting device comprises a plurality of series connected flip-flop devices; and b. the input to the first flip-flop of said plurality of series connected flip-flop devices being connected to the channel of said encoder having the highest pulse rate.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-06-28 | 1974-12-28 | 1975-06-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-06-28 | 1978-12-28 | 1979-06-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-06-28 | 1982-12-28 | 1983-06-29 | $7700.00 | Window Closed / Lapsed |