Hybrid drive apparatus and controller for hybrid drive apparatus

A hybrid drive apparatus comprising:

• a drive power source that includes an internal combustion engine, a first electric motor, and a second electric motor;
• a power transmission mechanism that includes
• a carrier that is coupled to an output shaft of the internal combustion engine and that rotatably supports plural pinion gears,
• a sun gear that is coupled to a rotational shaft of the first electric motor and that meshes with the pinion gears, and
• a ring gear that is coupled to a driving axle side and that meshes with the pinion gears, the power transmission mechanism being configured to rotate the output shaft of the internal combustion engine by the first electric motor;
• and
• plural bearings that each includes
• an outer ring member that is provided on an inner periphery of the ring gear;
• and
• an inner ring member that is provided on an outer periphery of a support portion of a case and that is rotatably fitted to the outer ring member through a rolling element,
• the bearings being provided apart from each other in an axial direction of the output shaft and the carrier being positioned between the bearings, wherein
• the bearings are each fitted onto the support portion of the case such that an inner periphery of the outer ring member of the bearing is positioned more inward in a radial direction of the ring gear relative to a meshing portion between inner teeth of the ring gear and outer teeth of one of the pinion gears.