Abstract: Under the condition of conservation tillage, in order to make the topsoil cultivation not disturb the upper and lower layer which can minimize the disturbance to the soil, to provide the ideal seedbeds, to increase the infiltration depth of water facilities sowing irrigation, to reduce the white pollution of water evaporation and coated water facilities sowing, to increase the sub-soiling depth, to reduce the frequency of cultivation joint to the fields, a kind of topsoil and subsoil combined cultivator is designed, which is with the function of reciprocating plug of soil as well as conducting sub-soiling operation. A topsoil cultivation tool structure is designed and the absolute motion mathematical model of the reliable operation of the surface tillage cutter is established. According to the test, if the broken soil coefficient of soil is more than 90% after topsoil cultivation, soil bulk density is less than 1.22 g/cm3, the upper and lower soil can not be disturbed, and when corn is using the water facilities sowing, the infiltration depth of water has an at least 19.3% increase than the same data of ordinary spin tillage method, then the reasonable cut soil distance of cutting tool should be less than 30 mm.

Key words: Conservation tillage, Equipment design, Loose soil, Soil disturbance, Watering and sowing