Sand making machine for building construction

The utility model relates to a sand making machine for building construction, which comprises a box body, a working cavity is arranged in the box body, and a granularity adjusting mechanism, a positioning and clamping mechanism and a convenient maintenance mechanism are arranged in the middle of the working cavity. The granularity adjusting mechanism comprises a threaded rod, a guide rod, four groups of adjusting blocks, an adjusting motor, two groups of crushing rollers, two groups of crushing motors and two groups of material guide plates, and when the granularity adjusting mechanism is used for adjusting the granularity of the sand making machine for building construction, the two groups of original material guide plates can be detached firstly; then an adjusting motor is operated to output in the forward direction or the reverse direction to drive a threaded rod to rotate, two sets of adjusting blocks on the front side can be driven to slide in the opposite direction or the reverse direction while the thr