Title:
LEVEL CONTROLLER OF LIQUID INJECTION TANK
Document Type and Number:
Japanese Patent JPS6290712
Kind Code:
A
Abstract:
PURPOSE:To prevent the liquid level fluctuation when liquid injection is started, by changing the span of the measuring output of a level sensor from the span at the time of stopping injection when the injection is started and the value of he level output is corrected so that the value can become the same value at the time of stopping injection, and then, smoothening the pulsating quantity through a time-lag-of- first-order filter means. CONSTITUTION:The output span of a level detecting means is changed between a fluid injection time and injection stopping time. Namely, gain setting means 12 and 13 for changing span which receive the measuring output EH of the level sensor are provided and the means 12 and 13 respectively output EH1 and EH2 after the means 12 multiplies the EH by a gain K1 when the injection is stopped and means 13 multiplies the EH by a gain K2 when a fluid is injected. The gains K1 and K2 are selected in such a way that the same measuring outputs EH1 and EH2 can be obtained to the same level H. The EH1 is selected at the time of stopping and EH2 is selected at the time of injection to a switching means 14 which is switched in accordance with the injecting and stopping conditions. The selected level measuring output is received by a time-lag-of-first-order filter means or moving average calculating means 15, and thus, a level measuring value PV, in which pulsating quantities put on the level measuring output are smoothened, is obtained.
Inventors:
IKEDA MIKIO
Application Number:
JP13859585A
Publication Date:
April 25, 1987
Filing Date:
June 25, 1985
Export Citation:
Assignee:
YOKOGAWA ELECTRIC CORP
International Classes:
G05D9/12; (IPC1-7): G05D9/12
Attorney, Agent or Firm:
Shinsuke Ozawa