DEVICE FOR CONTROL OF AUTOMOBILE ENGINE FAN Russian patent published in 1996 - IPC

FIELD: mechanical engineering. SUBSTANCE: device has temperature sensor 1 connected with inputs of two comparison circuits 3 and 4. Outputs of comparison circuits are connected with electronic switch 5 which is used to control operation of electric motor 7 of fan 8. Second input of each comparison circuits 3 and 4 is connected with respective set-up units 9 and 10 which preset command through voltage magnitude for switching on and switching off electric motor 7. Electronic switch is made in form of two- stage amplifier employing power and control transistors VT5 and VT3. Each set-up unit is made in form of voltage divider and both set-up units are connected to supply circuit in parallel; comparison circuits are composed of transistors. EFFECT: enhanced reliability. 3 dwg