Accessory drive for hybrid vehicles

摘要

A vehicle includes an internal combustion engine, a first hydraulic pump/motor coupled with the internal combustion engine, and a second hydraulic pump/motor is coupled with at least one driven wheel of the vehicle. A clutch establishes a driving connection between the first hydraulic pump/motor and the internal combustion engine, and selectively interrupts the driving connection when disengaged. At least one vehicle accessory device is coupled to the first hydraulic pump/motor. The at least one vehicle accessory device is operable under power of the internal combustion engine when the clutch is engaged and the internal combustion engine is running, and the at least one vehicle accessory device is operable directly by the first hydraulic pump/motor operating in a motor mode when the clutch is disengaged, regardless of whether or not the internal combustion engine is running. A corresponding method of operating the vehicle is also provided.

主权项

1. A vehicle comprising:
an internal combustion engine; a first hydraulic pump/motor coupled with the internal combustion engine to mechanically establish a driving connection therebetween, the first hydraulic pump/motor being operable in a pump mode to compress a hydraulic fluid under power of the internal combustion engine; a second hydraulic pump/motor coupled with at least one driven wheel of the vehicle to mechanically establish a driving connection therebetween, the second hydraulic pump/motor being operable in a motor mode to drive the at least one driven wheel when supplied with compressed hydraulic fluid; a clutch establishing the driving connection between the first hydraulic pump/motor and the internal combustion engine, the clutch being disengageable to selectively interrupt the driving connection between the first hydraulic pump/motor and the internal combustion engine; and at least one vehicle accessory device coupled to the first hydraulic pump/motor, wherein the at least one vehicle accessory device is operable under power of the internal combustion engine when the clutch is engaged and the internal combustion engine is running, and the at least one vehicle accessory device is operable directly by the first hydraulic pump/motor operating in a motor mode when the clutch is disengaged, regardless of whether or not the internal combustion engine is running; a third hydraulic pump/motor positioned between the first hydraulic pump/motor and the internal combustion engine, the third hydraulic pump/motor coupled with the internal combustion engine and the first hydraulic pump/motor to establish a driving connection therebetween, wherein the clutch is positioned between the first and third hydraulic pump/motors, and the first and third hydraulic pump/motors are simultaneously operable in different respective modes, chosen from a pump mode and a motor mode, when the clutch is disengaged, and are operable in a single combined mode, chosen from a pump mode and a motor mode, when the clutch is engaged.