Railway vehicle bottom door opening amplitude control device and railway vehicle

The invention provides a railway vehicle bottom door opening amplitude control device and a railway vehicle, and belongs to the field of railway vehicles, the railway vehicle bottom door opening amplitude control device comprises a stepped limiting disc and a telescopic limiting component, the stepped limiting disc is connected with a bottom door, and when the bottom door is opened, the stepped limiting disc can be driven to rotate; a plurality of steps are formed on the surface of one side of the stepped limiting disc, the telescopic limiting component can adjust the telescopic length to enable one end of the telescopic limiting component to be located in the rotating faces of the different steps so as to limit the different steps, then the rotatable angle of the stepped limiting disc is controlled, and the multiple steps form multiple gear locking. Gear switching of the opening amplitude of the bottom door is achieved, and various requirements of bottom door opening amplitude control, door opening and closi