| 摘要 |
1,152,792. Automatic fluid control. SOC. NATIONALE DES PETROLES D'AQUITAINE. May 4, 1966 [May 6, 1965], No. 60630/68. Divided out of 1, 152, 791. Heading G3R. Control apparatus for controlling the operation of a valve controlling the passage of fluid in a system comprises a voltage-frequency converter, means responsive to fluid-pressure in the system for converting this pressure into numerical values, a counter for integrating these values, a memory counter which is adapted to vary the capacity of the first said counter at will, and means including a logic element for controlling the operation of the valve in dependence upon a function of the pressure. The apparatus may be used to control the time of opening and duration of opening of the outlet valve of a high pressure ethylene polymerization reactor. In a preferred embodiment a pressure measuring instrument 11 supplies an analogue signal to a numerical analogue converter 12, pulses from 12 are counted in counter 14, when 14 is nearly full the penultimate pulse changes the state of the flip-flop unit 20 and opens the gate 21. The counter 23 is then filled to a certain value. The last pulse gives a signal causing change of state of the flip-flop unit 15 and cause the valve 16 to open. The same signal closes gate 21 and opens gate 24. The content of the auxiliary counter 23 is thus fixed and the counting back starts. When this is complete an end of counting signal is sent to the second input of the flip-flop unit 15 and this effects closing of the valve 16. |
