抄録
The automatic controller under study in this article comprises of the following apparatus: Process: Intersecting gill box Detecting element: High-frequency capacitance measuring equipment (Uster evenness tester) Final control element: Electro-hydraulic actuator; and PIV variable and device Control element: PID controller (Proportional-integral-differential)
We measured the steady-state characteristics of the detecting element under different conditions, sought an equation to express the steady-state characteristics and obtained the following results:
(1)Zero point sliver thickness G0 (the sliver thickness which makes the capacitance measuring equipment indicate zero point) is calculable by the following equation: G0=k1/r+k2 (d0-d) where k1 and k2 are constants determined by the kind of fiber and by the dimensions of the measuring condenser; r is the moisture content of the sliver measured; d indicates the deviation of the adjustment dial indication from the adjustment point; and d0 shows the same deviation of the adjustment dial indication at the zero point calculable by the following equation if our equipment is used: d0=1.099×104/√<14-Av>(12+Am)Ar where Av, Am and Ar are the amplifications of the equipment.
(2) The adjustment point varies very widely with the variations in the room temperature and, therefore, makes our equipment unfit for use outright as a detecting device.
We measured also the dynamic property of the detecting device, with the following result:
The time constant of the detecting device is 0.20sec. in Normal and 1.6sec. in Inert.
