Pump for e.g. removing water from pit or dyke, has flexible balloon shaped body on outside of casing for preventing dirt from entering

摘要

A flexible balloon-shaped body (11) is located inside or is in contact with the pump casing (3) so that at least part of it located outside this casing. The pump (1) comprises a fan (7) with a drive device (5) mounted inside the casing, a measuring device (9) for the level of liquid mounted inside or located outside the casing and a flexible balloon- shaped body connected in a liquid-tight manner to a pressure sensor (13) in the measuring device. The sensor measures liquid pressure or reacts to a given liquid pressure value being reached. Control of the drive device is determined by the measured liquid pressure.