Abstract: An apparatus for controlling a water pump having an engine that drives an impeller, a water storage tank connected to the water pump, a first water level detector that outputs an A signal when a water level is at or higher than a first height and outputs a B signal when lower than the height, a second water level detector that outputs the A signal when the water level is at or lower than a second height and outputs the B signal when higher than the height, a connection switcher that switches connection of the first and second water level detector, and an impeller controller connected to the connection switcher and adapted to control operation of the engine that drives the impeller of the water pump based on the signals outputted from the first and second water level detectors.

Abstract: An apparatus for controlling a water pump having an engine that drives an impeller, a water storage tank connected to the water pump, a first water level detector that outputs an A signal when a water level is at or higher than a first height and outputs a B signal when lower than the height, a second water level detector that outputs the A signal when the water level is at or lower than a second height and outputs the B signal when higher than the height, a connection switcher that switches connection of the first and second water level detector, and an impeller controller connected to the connection switcher and adapted to control operation of the engine that drives the impeller of the water pump based on the signals outputted from the first and second water level detectors.

Abstract: In an apparatus for controlling a general-purpose internal combustion engine having an electronic control unit (ECU) mounted on an electronic circuit board installed near a body of the engine and being connectable to a load such as an operating machine that consumes power generated by the engine, there are equipped with a first temperature sensor installed on the board at a position remote from the body and a second temperature sensor installed on the board at a position closer to the body than the first temperature sensor. A warm-up time period is determined based on an output of the first temperature sensor and a difference between outputs of the first and second temperature sensors, and an engine speed is controlled to a predetermined operating speed when the determined warm-up time period has elapsed (S18, S22), thereby improving the fuel efficiency and preventing engine stall.

Abstract: In an apparatus for detecting condition of load connected to a general-purpose internal combustion engine, a first threshold value is compared with a sum obtained by adding a predetermined value to a detected throttle opening and changes the threshold value to the sum if the first threshold value is less than the sum and the engine is determined to be under first load condition if the throttle opening exceeds the threshold value. Next a second threshold value is compared with a difference obtained by subtracting change amounts of the engine speed and throttle opening and the engine is determined to be under second load condition if the difference exceeds the second threshold value, thereby enabling to accurately detect a condition of a load connected to the engine. Then the desired engine speed is changed in response to results of the determinations.

Abstract: In an apparatus for controlling a general-purpose internal combustion engine having an electronic control unit (ECU) mounted on an electronic circuit board installed near a body of the engine and being connectable to a load such as an operating machine that consumes power generated by the engine, there are equipped with a first temperature sensor installed on the board at a position remote from the body and a second temperature sensor installed on the board at a position closer to the body than the first temperature sensor. A warm-up time period is determined based on an output of the first temperature sensor and a difference between outputs of the first and second temperature sensors, and an engine speed is controlled to a predetermined operating speed when the determined warm-up time period has elapsed (S18, S22), thereby improving the fuel efficiency and preventing engine stall.

Abstract: In an apparatus for detecting condition of load connected to a general-purpose internal combustion engine, a first threshold value is compared with a sum obtained by adding a predetermined value to a detected throttle opening and changes the threshold value to the sum if the first threshold value is less than the sum and the engine is determined to be under first load condition if the throttle opening exceeds the threshold value. Next a second threshold value is compared with a difference obtained by subtracting change amounts of the engine speed and throttle opening and the engine is determined to be under second load condition if the difference exceeds the second threshold value, thereby enabling to accurately detect a condition of a load connected to the engine. Then the desired engine speed is changed in response to results of the determinations.