HYDRAULIC PUMP ARRANGEMENT.

摘要

The invention relates to a hydraulic pump arrangement (3) comprising a housing (8) accommodating a first hydraulic piston pump unit (3a) having an input shaft (7) adapted to be connected to a power unit (4) of said vehicle drive system (1), thereby providing hydraulic pressure and flow to a first hydraulic circuit (6, 13). The invention furthermore comprises a second hydraulic pump unit (3b) arranged in series or in tandem with said first hydraulic pump unit (3a) and arranged to be mechanically connected to and driven by said input shaft (7), thereby providing hydraulic pressure and flow to a second hydraulic circuit (16, 17), which is hydraulically separated from said first hydraulic circuit (6, 13).