Concrete crushing device

The utility model relates to the field of building material processing equipment, in particular to a concrete crushing device. The crushing device comprises a shell, a crushing wheel is arranged in the shell, a pressing plate connected with a lifting device is arranged above the crushing wheel and connected with a centering device, the centering device comprises a horizontally-arranged horizontal rack, the upper end of the horizontal rack is meshed with the lower end of a connecting gear, and the side end of the connecting gear is meshed with a vertical rack. The vertical rack is connected with the pressing plate through a connecting rod. The technical scheme has the beneficial effects that materials between the crushing wheels are pressed through the pressing plate, so that the materials can quickly descend, the crushing process of the crushing wheels on waste concrete is accelerated, when the pressing plate descends, the vertical rack is driven to descend, when the vertical rack moves, the connecting gear i