Patent ID: 7111704
Filing Date: 2006-09-26
Classification: B60K,Y02T

Abstract:
1. Hydrostatic drive apparatus for a road vehicle, comprising in combination: an internal combustion engine; a hydrostatic drive including a first hydraulic machine selectively operated as a pump or a motor and mechanically coupled to said engine, at least one hydraulic drive motor fluidically coupled to said first hydraulic machine and mechanically coupled to a drive wheel of said vehicle to propel said vehicle when said first hydraulic machine is operated as a pump; an electric machine; a storage battery electrically coupled to said electric machine; a second hydraulic machine selectively operated as a pump or a motor, mechanically coupled to said electric machine and fluidically coupled to said first hydraulic machine; and a controller effective (1) during a cranking mode of operation to operate said first and second hydraulic machines as motor and pump, respectively, so that said electric machine is driven by said storage battery to supply fluid from said second hydraulic machine to said first hydraulic machine to crank said internal combustion engine, and (2) during a run mode of operation to operate said first and second hydraulic machines as pump and motor, respectively, so that fluid is supplied from said first hydraulic machine to said second hydraulic machine for mechanically driving said electric machine to generate charging current for said storage battery.