Study On The Engine's Power Property And Transmission Type Of The Bulldozers

In this paper, the influence of the mutative load operating mode on engine's property and the present evaluation criterion (the characteristic factor of torque-load K_m and the accommodation factor of speed ) of engine's power reserve property for bulldozer are mainly researched. It is pointed out that K_m and K_n can't comprehensively reflect engine's power reserve property. Therefore a new comprehensive evaluation criterion (power reserve factor K) of power reserve property is suggested and formulated. Through the compare and analysis of the transmission type of the present bulldozers, hydrostatic transmission and hydrodynamic transmission and their application in bulldozer are studied, and hydraulic bulldozer and hydro-mechanical bulldozer are contrasted and analyzed detailedly in structure, control, efficiency, traction property and manufacture cost etc. The key parameters of bulldozer, slip ratio, force-to-weight ratio and power-to-weight ratio, are researched. It is proved in theory that the selection of rated slip ratio of bulldozer has done with the transmission type of bulldozer. It is pointed out that the force-to-weight ratio and power-to-weight ratio of hydrostatic bulldozer is bigger than that of hydro-mechanical bulldozer, and with the increase of engine power, the force-to-weight ratio of both will decline. It is confirmed separately that the means of force-to-weight ratio and power-to-weight of hydrostatic bulldozer and hydro-mechanical bulldozer, which would be theoretical basis in design. Taking the hydrostatic bulldozer TQ160C as the prototype, the match theory of hydrostatic bulldozers are researched by both ways of theory and practice. Through the analysis on the data of traction property test, the parameter match of each grade of TQ160C, the match point of engine and the control signal of pumps and motors are studied.