US Patent 7347802 Clutch control apparatus for hybrid vehicle

A clutch control apparatus for a hybrid vehicle (1) having an engine (2) and a motor (3) as power sources, and an output shaft (13a). The clutch control apparatus includes a clutch device (12) and a clutch control device (19) operatively connected to the clutch device (12) for controlling the engagement degree of the clutch device (12) when the driving mode of the vehicle is alternately switched between an engine cruise mode and a motor cruise mode. The clutch control device (19) is adapted to execute a clutch relaxation control operation which includes an engagement decreasing control operation and a subsequent engagement recovery control operation, and is further adapted to execute an engagement increasing control operation in which the engagement degree of the clutch device (12) is forced to increase when the revolution rate of the engine (2) falls below a predetermined value.