A hydro-mechanical hybrid transmission device with two hydraulic transmission mechanisms includes an input member, a second hydraulic transmission mechanism, a rear planetary gear mechanism, an output member, a first hydraulic transmission mechanism, a front planetary gear mechanism, a clutch assembly, and a brake assembly. The clutch assembly connects the input member to the front planetary gear mechanism, the second hydraulic transmission mechanism, and the first hydraulic transmission mechanism, connects an output end of the first hydraulic transmission mechanism to the front planetary gear mechanism, connects the rear planetary gear mechanism to an output end of the second hydraulic transmission mechanism and the front planetary gear mechanism, and connects the rear planetary gear mechanism to the output member. The clutch assembly and the brake assembly provide a continuous transmission ratio between the input member and the output member.

A hydro-mechanical hybrid transmission device with two hydraulic transmission mechanisms includes an input member, a second hydraulic transmission mechanism, a rear planetary gear mechanism, an output member, a first hydraulic transmission mechanism, a front planetary gear mechanism, a clutch assembly, and a brake assembly. The clutch assembly connects the input member to the front planetary gear mechanism, the second hydraulic transmission mechanism, and the first hydraulic transmission mechanism, connects an output end of the first hydraulic transmission mechanism to the front planetary gear mechanism, connects the rear planetary gear mechanism to an output end of the second hydraulic transmission mechanism and the front planetary gear mechanism, and connects the rear planetary gear mechanism to the output member. The clutch assembly and the brake assembly provide a continuous transmission ratio between the input member and the output member.

A hydro-mechanical hybrid transmission device with two hydraulic transmission mechanisms includes an input member, a second hydraulic transmission mechanism, a rear planetary gear mechanism, an output member, a first hydraulic transmission mechanism, a front planetary gear mechanism, a clutch assembly, and a brake assembly. The clutch assembly connects the input member to the front planetary gear mechanism, the second hydraulic transmission mechanism, and the first hydraulic transmission mechanism, connects an output end of the first hydraulic transmission mechanism to the front planetary gear mechanism, connects the rear planetary gear mechanism to an output end of the second hydraulic transmission mechanism and the front planetary gear mechanism, and connects the rear planetary gear mechanism to the output member. The clutch assembly and the brake assembly provide a continuous transmission ratio between the input member and the output member.

A power-takeoff (PTO) unit for a work vehicle includes a planetary gear driven by an engine of the work vehicle; a PTO spline connected in power transmission to the planetary gear and defining a gear ratio; a hydrostatic transmission driven by the planetary gear to control the gear ratio; a pressure sensor unit for sensing a differential pressure across a loop of the hydrostatic transmission; and a control unit. The control unit is configured to calculate a differential pressure in the loop from a calibration mathematical model representing an unloaded functioning of the PTO spline. The control unit is also configured to calculate a PTO spline torque from a further mathematical model. The model is based on the pressure drop, on pressure signals from the sensor unit, and on kinematic or hydraulic factors of the planetary gear and the hydrostatic transmission.

A power-takeoff (PTO) unit for a work vehicle includes a planetary gear driven by an engine of the work vehicle; a PTO spline connected in power transmission to the planetary gear and defining a gear ratio; a hydrostatic transmission driven by the planetary gear to control the gear ratio; a pressure sensor unit for sensing a differential pressure across a loop of the hydrostatic transmission; and a control unit. The control unit is configured to calculate a differential pressure in the loop from a calibration mathematical model representing an unloaded functioning of the PTO spline. The control unit is also configured to calculate a PTO spline torque from a further mathematical model. The model is based on the pressure drop, on pressure signals from the sensor unit, and on kinematic or hydraulic factors of the planetary gear and the hydrostatic transmission.

Continuously variable hydro-mechanical transmission includes an input shaft and an output shaft, a torque converter and an eccentric gear set including at least one main gear, a planet gear, a main eccentric and an auxiliary eccentric of adaptable eccentricity, wherein the input shaft is connected to the turbine rotor and one member of the eccentric gear set, the pump rotor is connected to another member of the eccentric gear set, and the output shaft is connected to yet another member of the eccentric gear set. This arrangement introduces strong positive feedback between the pump rotor and the turbine rotor, which results in large maximum torque ratio and large rate of growth of torque ratio, as well as large ratio spread, which can be adapted by changing eccentricity of the auxiliary eccentric.

A power-takeoff (PTO) unit for a work vehicle includes a planetary gear driven by an engine of the work vehicle; a PTO spline connected in power transmission to the planetary gear and defining a gear ratio; a hydrostatic transmission driven by the planetary gear to control the gear ratio; a pressure sensor unit for sensing a differential pressure across a loop of the hydrostatic transmission; and a control unit. The control unit is configured to calculate a differential pressure in the loop from a calibration mathematical model representing an unloaded functioning of the PTO spline. The control unit is also configured to calculate a PTO spline torque from a further mathematical model. The model is based on the pressure drop, on pressure signals from the sensor unit, and on kinematic or hydraulic factors of the planetary gear and the hydrostatic transmission.

A power-takeoff (PTO) unit for a work vehicle includes a planetary gear driven by an engine of the work vehicle; a PTO spline connected in power transmission to the planetary gear and defining a gear ratio; a hydrostatic transmission driven by the planetary gear to control the gear ratio; a pressure sensor unit for sensing a differential pressure across a loop of the hydrostatic transmission; and a control unit. The control unit is configured to calculate a differential pressure in the loop from a calibration mathematical model representing an unloaded functioning of the PTO spline. The control unit is also configured to calculate a PTO spline torque from a further mathematical model. The model is based on the pressure drop, on pressure signals from the sensor unit, and on kinematic or hydraulic factors of the planetary gear and the hydrostatic transmission.

A rotational power transmission apparatus is provided including an input coupler having first and second input shafts, a differential engine coupled to the first input shaft and transmitting power to a first output shaft. First and second one-way bearings are coupled to the first output shaft. A first torque converter is coupled to the first one-way bearing, and a second torque converter coupled to the second one-way bearing. An output coupler is coupled to output from the first torque converter, output from the second torque converter and a second output shaft.

A rotational power transmission apparatus is provided including an input coupler having first and second input shafts, a differential engine coupled to the first input shaft and transmitting power to a first output shaft. First and second one-way bearings are coupled to the first output shaft. A first torque converter is coupled to the first one-way bearing, and a second torque converter coupled to the second one-way bearing. An output coupler is coupled to output from the first torque converter, output from the second torque converter and a second output shaft.