| 摘要 |
PURPOSE: A water feed controller of an evaporation type condenser is provided to control a pump by using a latch IC(Integrated Circuit) instead of a microcomputer to control the pump depending on the water level of a water tub. CONSTITUTION: A high signal is input to a set terminal(Set) of a latch(201) if the lowest water level is detected from a first lead switch(101) of a water level sensor(100). The high signal is output to a first relay(203), and the first relay is excited to start driving a pump(204). The water level of a water tub gets lower, and the latch outputs a signal to drive the pump even though the water level falls lower than the lowest water level. If the highest water level is detected from a second lead switch(102), a second relay is excited and a water feed valve(302) is closed to stop supplying water. After power on/off, a reset unit(202) charges power to a capacitor(C1). The charging time of the capacitor and the signal input of the latch are decided by an RC(Resistance/Capacitance) time constant. The latch is initialized by a high signal according to the RC time constant. The latch outputs a signal for driving the pump when the lowest water level is detected from the first lead switch. When the power is off again, the capacitor is discharged and a signal is not input to the reset terminal(Reset) of the latch.
|
