Hydraulic elevator system
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United States of America Patent
Stats
-
Jun 12, 1990
Grant Date -
N/A
app pub date -
Feb 15, 1989
filing date -
Feb 15, 1989
priority date (Note) -
Expired
status (Latency Note)
Importance
Abstract
A hydraulic elevator system 10 having an elevator car 12 in which car velocity V and car position L are determined by detecting the quantity Q of hydraulic fluid transferred between a hydraulic cylinder and a hydraulic fluid reservoir. The car velocity V is directly proportional to Q and the car position L is directly proportional to the integral of Q. The car velocity V, or quantity Q, is compared with a desired velocity pattern, or desired flow rate pattern, PG, and the difference is a control signal C which is used to control the quantity Q. The car position L may also be used to determine the distance-to-go to a target floor, which may be used to initiate slowdown and/or to calculate all, or selected portions of, the desired pattern PG.
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Family
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Cited Art Landscape
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