Chapter 16 Vehicle automatic transmission 同©大学 TONGII UNIVERSTTY The operating principle of fluid coupling hydraulic B transmission water pump aulqing rew Ostop play rew Ostop
Chapter 16 Vehicle automatic transmission The operating principle of fluid coupling
Chapter 16 Vehicle automatic transmission 同©大学 TONGII UNIVERSTTY The working process of fluid coupling >When the running wheel is rotating,the working fluid is driven to rotate together by impeller turbine the vanes. flow >As the effect of the centrifugal force,the direction working fluid flows from the inner edge to the outer edge of the vane. >The pressure of the outer is high while the inner is low. >The pressure difference between the inner and the outer of the vane depends on the radius and speed of the running wheel
Chapter 16 Vehicle automatic transmission When the running wheel is rotating, the working fluid is driven to rotate together by the vanes. As the effect of the centrifugal force, the working fluid flows from the inner edge to the outer edge of the vane. The pressure of the outer is high while the inner is low. The pressure difference between the inner and the outer of the vane depends on the radius and speed of the running wheel. The working process of fluid coupling
Chapter 16 Vehicle automatic transmission 同©大学 TONGII UNIVERSTTY The working process of fluid coupling >The radius of the impeller equals to that of the turbine. impeller turbine >When the speed of the impeller is higher than that of the turbine,the hydraulic flow pressure of the outer edge of the impeller direction vane is higher than that of the turbine vane. >The working fluid not only does circular motion following the running wheel around the crankshaft and the driven shaft,but also,under the pressure difference,does cyclic motion along the direction indicated by the arrow of the circular circle. >The flow line of the liquid particles forms a both linked annular helix line
Chapter 16 Vehicle automatic transmission The working process of fluid coupling The radius of the impeller equals to that of the turbine. When the speed of the impeller is higher than that of the turbine, the hydraulic pressure of the outer edge of the impeller vane is higher than that of the turbine vane. The working fluid not only does circular motion following the running wheel around the crankshaft and the driven shaft, but also, under the pressure difference, does cyclic motion along the direction indicated by the arrow of the circular circle. The flow line of the liquid particles forms a both linked annular helix line
Chapter 16 Vehicle automatic transmission 同©大学 TONGII UNIVERSTTY The working process of fluid coupling >The impeller apply work to the working fluid,so impeller turbine that during flowing from the inner to the outer edge of the impeller vane,the Circumferential velocity and kinetic energy of the fluid is gradually increased; flow >During flowing from the outer to the inner edge of direction the turbine vane,the circumferential velocity and kinetic energy of the fluid is gradually decreased. >The working process of fluid coupling:the impeller accepts mechanical energy from the engine and passes it to the working fluid,then the kinetic energy of the fluid increases and passes the energy to the turbine,finally the turbine outputs power. crankshaft Input shaft impeller turbine Output shaft
Chapter 16 Vehicle automatic transmission The impeller apply work to the working fluid, so that during flowing from the inner to the outer edge of the impeller vane, the Circumferential velocity and kinetic energy of the fluid is gradually increased; During flowing from the outer to the inner edge of the turbine vane, the circumferential velocity and kinetic energy of the fluid is gradually decreased. The working process of fluid coupling: the impeller accepts mechanical energy from the engine and passes it to the working fluid, then the kinetic energy of the fluid increases and passes the energy to the turbine, finally the turbine outputs power. crankshaft Input shaft impeller turbine Output shaft The working process of fluid coupling
Chapter 16 Vehicle automatic transmission 同©大学 TONGII UNIVERSTTY The necessary condition of the transmission of fluid coupling >The reason of the circular flow of the >The necessary condition: working fluid is that it exists pressure It exists circular flow of the difference in the outer edge of the working fluid between the working wheel vane which is attributed impeller and the turbine. to the difference of the two working wheels speeds. >when the hydraulic coupler works properly,the >If the two speeds are equal, impeller speed is always the hydraulic coupler doesn't faster than the turbine drive. speed
Chapter 16 Vehicle automatic transmission The necessary condition of the transmission of fluid coupling The necessary condition: It exists circular flow of the working fluid between the impeller and the turbine. The reason of the circular flow of the working fluid is that it exists pressure difference in the outer edge of the working wheel vane which is attributed to the difference of the two working wheels speeds. when the hydraulic coupler works properly, the impeller speed is always faster than the turbine speed. If the two speeds are equal, the hydraulic coupler doesn’t drive