Vehicle driving device

Abstract

A vehicle driving device includes: an engine; a brake booster including a negative pressure chamber, the brake booster amplifying a brake pressure by a negative pressure determined corresponding to a pressure inside the negative pressure chamber; a power transmission clutch disposed between the engine and a driving wheel; and a negative pressure pump configured to drive by using at least one of a torque from the engine and a torque from the driving wheel, the negative pressure pump being configured to vary the negative pressure inside the negative pressure chamber. In the vehicle driving device included in a vehicle that performs freewheeling in a state where the power transmission clutch is released and the engine is stopped, the negative pressure pump includes a control chamber configured to reduce a capacity of the negative pressure pump as a magnitude of the negative pressure inside the negative pressure chamber increases.

Dependencies are inferred from the claim text.