Throw-in type liquid level sensor protection sleeve for water-turbine generator set top cover water collection tank

A protective sleeve for a throw-in type liquid level sensor of a top cover water collecting tank of a water-turbine generator set comprises a sleeve body, the lower end of the sleeve body is connected with a filter connector in a clamped mode, and one side of the filter connector is welded to the lower portion of the water collecting tank. The filtering connector comprises a clamping sleeve, a mounting hole is formed in the clamping sleeve, a filtering sleeve and a base plate are arranged in the mounting hole, a hollow screw rod is screwed into the clamping sleeve and jacks up the filtering sleeve and the base plate, a plurality of clamping holes are formed in the side wall of the clamping sleeve at the upper end of the filtering sleeve in the circumferential direction, clamping balls are arranged in the clamping holes, and when the filtering sleeve moves upwards, the clamping balls are inserted into the clamping holes. And the clamping ball is ejected out of the clamping hole and is clamped with the through