SWITCHING DEVICE Russian patent published in 1999 - IPC

FIELD: automatic control; switching automatic-control members in definite sequence with desired time delay and automatic interlocking. SUBSTANCE: known structure that has normally open control (start) button, time- setting delay member, bipolar transistor switch controlling light-triggered power thyristor, and limiting resistor inserted in input circuit of the latter is provided, in addition, with supply energy metering circuits, pre-start and protective circuits, isolating rectifier diode, and two jumpers installed for opening the circuit. In addition, time-setting delay member uses different structure. Proposed device has single-junction transistor, two field-effect transistors with p-n junction, two low-power light-triggered thyristors, three capacitors, two bipolar transistors, two rectifier diodes, and twelve resistors. EFFECT: improved insulation of control and power actuating circuits, increased maximum rate of liquid dispensing process, facilitated connection to personal computer, improved operating reliability and service life. 3 cl, 3 dwg