Patent ID: 7641009

Claim:
A power output apparatus constructed to output power to a driveshaft, the power output apparatus comprising: an internal combustion engine; an electric power-mechanical power input output assembly connected with the driveshaft and with an output shaft of the internal combustion engine in a rotatable manner independently of the driveshaft and configured to output a torque to the driveshaft and to the output shaft through input and output of electric power and mechanical power; a motor designed to input and output power from and to the driveshaft; an accumulator arranged to transmit electric power to and from the electric power-mechanical power input output assembly and the motor; an oxygen content detector located in an exhaust system of the internal combustion engine and designed to measure a concentration of oxygen included in an exhaust gas of the internal combustion engine; a charge level computation module configured to compute a charge level of the accumulator; a driving force demand setting module configured to set a driving force demand required for the driveshaft; and a controller configured to respond to an abnormality detection request for executing abnormality detection to identify abnormality or normality of the oxygen content detector during operation of the internal combustion engine, wherein when the computed charge level of the accumulator is lower than a preset reference charge level, said controller determines non-execution of the abnormality detection of the oxygen content detector regardless of the abnormality detection request, while controlling the internal combustion engine, the electric power-mechanical power input output assembly, and the motor to ensure output of a driving force corresponding to the set driving force demand to the driveshaft, and wherein when the computed charge level of the accumulator is not lower than the preset reference charge level, said controller determines to cut off a fuel supply to the internal combustion engine and execute the abnormality detection of identifying abnormality or normality of the oxygen content detector based on an output of the oxygen content detector, while controlling the internal combustion engine, the electric power-mechanical power input output assembly, and the motor to ensure output of a driving force corresponding to the set driving force demand to the driveshaft.