Floor sweeping mechanism and floor sweeping robot

The utility model relates to a sweeping mechanism which is used for being installed on a sweeping robot and comprises an installation shell, a rolling brush, a conveying belt assembly and a tensioning assembly. The mounting shell is provided with a mounting cavity; the rolling brush is accommodated in the mounting cavity and is rotationally connected with the shell wall of the mounting shell; the conveying belt assembly comprises a conveying belt which is in transmission connection with the rolling brush and can drive the rolling brush to rotate around the rotation axis of the rolling brush. The tensioning assembly is connected with the mounting shell and comprises a tensioning piece and an adjusting piece connected with the tensioning piece; the tensioning piece can be driven by the adjusting piece to be close to or away from the conveying belt so that the tensioning piece can abut against the conveying belt and adjust the tensioning degree of the conveying belt. Before the sweeping robot is used, the tensio