Patent ID: 8209968
Filing Date: 2012-07-03
Classification: B60K,B60L,B60W,F02D,Y02T

Abstract:
1. A hybrid vehicle comprising: an engine; an electric motor; a power transmitting portion, including a planetary gear unit, that transmits output from the engine to a driving wheel and transmits output from the electric motor to the driving wheel; an electronic control unit (ECU) including an output control portion having instructions, which, when implemented, control an output ratio of the engine and an output ratio of the electric motor using the power transmitting portion according to a running state of the vehicle; and a NO a three-way catalyst provided upstream, in a direction in which exhaust gas flows, of the NO wherein the ECU further includes an operating mode switching portion having instructions, which, when implemented, switch an operating mode of the engine between a lean burn operating mode in which an air-fuel ratio of the engine is lean, a stoichiometric burn operating mode in which the air-fuel ratio of the engine is near a stoichiometric air-fuel ratio, and a rich burn operating mode in which the air-fuel ratio of the engine is rich, wherein the output control portion has further instructions, which, when implemented, increase the output ratio of the electric motor and delays a timing at which an increase of the output of the electric motor is started with respect to a timing at which the operating mode is switched by a predetermined period of time, the predetermined period of time being an amount of time required for exhaust gas for recovering the NO wherein the output control portion has further instructions, which, when implemented, make a speed of the engine constant for a predetermined period of time and selectively increase or decrease the output of the electric motor when the operating mode is switched by the operating mode switching portion.