Gravel crushing device for building construction

The invention discloses a building construction gravel crushing device which comprises a box body, a first through hole is formed in the box body, a first shaft rod is rotatably connected to the interior of the first through hole, and a first crushing roller is arranged on the surface of one end of the first shaft rod. According to the building construction gravel crushing device, a first electric push rod, an adjusting rod, an adjusting sleeve, a polygonal extrusion plate, a crushing head, a connecting plate and a first spring are arranged in a matched mode, the first electric push rod stretches to drive the adjusting rod to stretch out, under the action of a spiral sliding groove, a sliding block is matched, the adjusting sleeve is driven to rotate, and then the polygonal extrusion plate is driven to rotate; and a polygonal extrusion plate extrudes a connecting plate, a crushing head slides in a connecting sliding groove, a first spring is extruded, and the extension amount of the crushing head is adjusted,