Reverse Design Of A New Type Hydraulic Static Transmission Device

In this paper, a new type Hydraulic Static Transmission device working in half-feedcombine harvest was reversely designed. Based on the determination of its operationalprinciple and the completion of the3-D CAD modeling, following researches wereconducted:First, force analysis was carried out to the key shaft(the power input shaft), followed bythe calculation of its strength、stiffness and critical rotation speed, which could provide atheoretical basis for2nd-design;Then, in order to realize the domestic manufacture in the future, an improvement designwas made for two pair of important gear transmissions to the cutting table. The correspondingdimensional parameters, as well as their modifying coefficients, were reversely designed. Andthe tooth root bending fatigue strength and the tooth surface contact fatigue strength were alsocalculated, which presented the experiences for the purpose of domestic manufactures;Finally, we re-designed the controlling cam in the steering system. The geometryrelationship was achieved between the cam、relief valve and reversing valve, followed by theestablishment of the cam contour line and its optional curve fitting, resulting in animprovement of the cam’s machinability and the steering function. All these designapproaches, as well as the formulas, can be references for the modifications to the nextgenerations of the HST devices.This paper provided a valuable reference in terms of theory and design method for thestudy of the mechanical transmission in this new type HST device, laying a foundation for thelocalization of the manufacture of the device.