Hydrostatic continuously variable transmission

摘要

The invention relates to a hydrostatic continuously variable transmission with a simple structure, which merely involves changing the phase angle in the direction of eccentricity of the first eccentric ring arranged off center with respect to the axis (A) so as to operate the first distributing valves of the hydraulic pump (P) having a swash plate with a fixed angle of inclination, makes it possible to obtain any gear ratio up to infinity beyond the gear ratio range obtained by varying the volume of the hydraulic motor (M) having a swash plate with a variable angle of inclination. Furthermore, the gear ratio can be reliably controlled because the aforementioned gear ratio is univocally determined according to the phase angle in the direction of eccentricity of the first eccentric ring and does not change according to the magnitude of the load on the output side. It is thus possible to increase the output side torque so as to allow the vehicle to get underway smoothly by increasing the gear ratio at the time the vehicle gets underway, for example.