Automatic multi-stage crushing device for building concrete production

The utility model discloses an automatic multi-stage crushing device for building concrete production, which comprises a box body, the bottom of the box body is fixedly connected with a first shell, the left side of the first shell is fixedly connected with a second shell, and the inner wall of the box body is movably connected with a first rotating rod through a bearing; the surface of the first rotating rod is sleeved with an extrusion roller, and the left side of the back face of the box body is fixedly connected with a first motor. Through cooperation of the box body, the first shell, the second shell, the first rotating rod, the extrusion roller, a first motor, a second rotating rod, a third rotating rod, a first gear, a second gear, a crushing rod, a second motor, an inclined block, an electric telescopic rod, an extrusion plate, a groove, a sliding rod and a sliding sleeve, the purpose of a good use effect is achieved; and building concrete raw materials can be subjected to multi-stage crushing, so tha