Abstract: The application relates to a pump apparatus for pumping liquid, and more particularly to a technique for removing foreign matters contained in the liquid when an impeller catches on the foreign matters. The pump apparatus includes: an impeller (1); an electric motor (7) configured to rotate the impeller (1); an inverter (14) configured to drive the electric motor (7); a current measuring device (15) configured to measure a current supplied to the electric motor (7); and an operation controller (17) configured to instruct the inverter (14) to cause the impeller (1) to perform a foreign-matter removing operation including at least two of: an intermittent operation that intermittently rotates the impeller (1) in a forward direction; a reverse-rotating operation that rotates the impeller (1) in a reverse direction; and a forward and reverse inching operation that rotates the impeller (1) in the reverse direction and the forward direction alternately and repeatedly.

Abstract: A pump apparatus which can save space and is easy to handle is proposed. The pump apparatus includes a pipe-shaped casing including a suction port and a discharge port arranged in the same straight line and defining a flow channel that connects the suction port and the discharge port; a motor disposed inside the casing, the motor including a rotating shaft extending along a flow channel direction directing from the suction port to the discharge port, a rotor rotating integrally with the rotating shaft, a stator provided on an outer peripheral side of the rotor, and a can for isolating a rotor chamber and a stator chamber, the rotor chamber having the rotor disposed therein and the stator chamber having the stator disposed therein; and an inverter disposed in the interior of the casing for exercising variable speed control over the motor.