A variable drive system of a power system is disclosed. The variable drive system may include an engine gearset to transfer power from an engine output of an engine to a variable input driveshaft of the variable drive system. The variable drive system may include a generator gearset to transfer power, generated by the engine, to a generator driveshaft of a generator. The variable drive system may include a variable drive, coupled to the variable input driveshaft, to enable a gear ratio between engine output and the generator driveshaft to be adjustable, the variable input driveshaft being offset from at least one of the engine output or the generator driveshaft. The variable drive system may include a direct drive clutch to bypass variable power transfer through the variable drive and enable direct power transfer from the engine output to the generator driveshaft.

A power split transmission which has a first part (2) and a second part (22) The first part (2) includes a variator (10), a summing gearset (6) and a shiftable transmission gear assembly (18). A standard transmission can be used as the multispeed transmission (23).

A power split transmission which has a first part (2) and a second part (22) The first part (2) includes a variator (10), a summing gearset (6) and a shiftable transmission gear assembly (18). A standard transmission can be used as the multispeed transmission (23).

A hydraulic control system HCS for controlling a variable ratio transmission of a power generating system. A hydraulic motor/pump unit 140 is operably connected to a superposition gear, and is connected to a hydraulic circuit that comprises an orifice 28 and/or a relief valve 29 that opens at a predetermined hydraulic pressure. The hydraulic circuit switches between a variable low-speed operating mode and a torque limiting high-speed operating mode. In the torque limiting high-speed operating mode the hydraulic motor/pump unit 140 is driven by the superposition gear and drives hydraulic fluid through the orifice 28 and/or relief valve 29 to provide a passive torque limiting function. In the variable low-speed operating mode the hydraulic motor/pump unit 140 drives the superposition gear and the hydraulic control system provides a desired rotor 101 speed by controlling hydraulic fluid flow rate through the hydraulic motor/pump unit 140.

A hydraulic control system HCS for controlling a variable ratio transmission of a power generating system. A hydraulic motor/pump unit 140 is operably connected to a superposition gear, and is connected to a hydraulic circuit that comprises an orifice 28 and/or a relief valve 29 that opens at a predetermined hydraulic pressure. The hydraulic circuit switches between a variable low-speed operating mode and a torque limiting high-speed operating mode. In the torque limiting high-speed operating mode the hydraulic motor/pump unit 140 is driven by the superposition gear and drives hydraulic fluid through the orifice 28 and/or relief valve 29 to provide a passive torque limiting function. In the variable low-speed operating mode the hydraulic motor/pump unit 140 drives the superposition gear and the hydraulic control system provides a desired rotor 101 speed by controlling hydraulic fluid flow rate through the hydraulic motor/pump unit 140.

A variable displacement oil pump includes: a variable displacement mechanism that is able to change a discharge amount per rotation of an input shaft. The variable displacement mechanism includes a pump housing, an oil pressure chamber provided in the pump housing, and a capacity adjustment member displaced by oil pressure from the oil pressure chamber. The capacity adjustment member is configured to be operated when receiving control oil pressure that is supplied from a control valve to the oil pressure chamber. The pump housing has an oil release hole that is opened to face the oil pressure chamber and that penetrates a wall section of the pump housing to partially release oil.

A variable displacement oil pump includes: a variable displacement mechanism that is able to change a discharge amount per rotation of an input shaft. The variable displacement mechanism includes a pump housing, an oil pressure chamber provided in the pump housing, and a capacity adjustment member displaced by oil pressure from the oil pressure chamber. The capacity adjustment member is configured to be operated when receiving control oil pressure that is supplied from a control valve to the oil pressure chamber. The pump housing has an oil release hole that is opened to face the oil pressure chamber and that penetrates a wall section of the pump housing to partially release oil.

An automobile or other wheeled vehicle includes various hydraulic components, including a hydraulic gearbox, transmission, clutch, and brake energy recovery system. Such hydraulic components supplement or replace traditional mechanical components of the automobile or other wheeled vehicle to improve the overall operational efficiency thereof.

A speed-changing device (21) is provided with an input shaft (22), an output shaft (23), a planetary gear mechanism (29), a first variator (33), a second variator (34), and a controller (25). The planetary gear mechanism (29) is configured to include a carrier (29A) connected to the input shaft (22), a first sun gear (29B) connected to the first variator (33), and a second sun gear (29C) connected to the output shaft (23). The second variator (34) transmits power transmitted from the first variator (33) to the output shaft (23), or transmits power transmitted from the output shaft (23) to the first variator (33). The controller (25) changes the rotation speed of the first variator (33), thereby changing the rotation speed of the output shaft (23) in relation to the rotation speed of the input shaft (22).

A micro-traction drive unit according to the present invention includes an inner ring, an outer ring, a plurality of rolling elements, a retainer, a micro-traction drive case and a power-transmitting shaft coaxial with the inner ring and incapable of relative rotation around an axis to the retainer. An opposite end of the power-transmitting shaft from the inner ring forms an input end operatively connected to a driving source. An input end of the pump shaft is detachably connected to a central hole of the inner ring in a state incapable of relative rotation around the axis via the access opening of the micro-traction drive case by connecting the micro-traction drive case to the HST case so as to surround the input end of the pump shaft of the HST.