Seedling-protecting, soil-cutting, rotary-tilling and pressing combined device

The invention provides a combined soil preparation machine with functions of seedling protection, soil cutting, ditching, rotary tillage, soil crushing, pressing and soil moisture conservation for crops such as vegetables and corns. The combined soil preparation machine comprises three parts: firstly, a breast board type seedling protection device is designed, and crop stems and leaves are pushedto the peripheries of a disc cutter and a rotary cultivator during operation, so that the stems and leaves are prevented from being cut; secondly, a disc type soil cutting device is designed and installed on a machine body of a common mini-tiller, the position of a cutter head is adjusted according to the row spacing of the crops during operation, a soil cutting disc is tightly attached to the roots of the crops to cut soil according to the growth characteristics of roots of the crops, and small ponding ditches are formed; and thirdly, a rear output shaft of the common mini-tiller is connectedwith the rotary cultivato