Differential device and drive power transmission unit using the same

A differential device comprising;

• an input shaft receiving a torque from a first power source;
• a differential mechanism having
• an input element receiving the torque from the first power source through the input shaft,
• a first output element,
• a second output elements, and
• gear elements for distributing the torque transmitted from the input element to the two output elements with allowing the differential rotation therebetween;
• a first sun gear connected to the input element to integrally rotate with the input element and disposed around the first output element to be coaxial with the first output element;
• a second sun gear disposed around the first output element to be coaxial with the first output element, wherein the number of the teeth of the second sun gear is slightly different from that of the first sun gear;
• first planetary gears meshing with both the first sun gear and the second sun gear;
• a first carrier supporting the first planetary gears around the first and second sun gears with allowing the planetary gears to rotate around its center axis and to revolve to go around the first and second sun gears;
• a third sun gear connected to the first output element to integrally rotate with the first output element around the same axis as the first output element, wherein the number of the teeth of the third sun gear is same as that of the first sun gear;
• second planetary gears meshing with both the second sun gear and the third sun gear;
• a second carrier supporting the second planetary gears around the second and the third sun gears with allowing the planetary gears to rotate around its center axis and with preventing the planetary gears from revolving to go around the second and third sun gears;
• and
• a second power source generating a torque for rotating the first carrier around its center axis.