Automatic transmission system for vehicle

An automatic transmission system for a vehicle comprising a torque convertor;

• a forward-reverse switching mechanism;
• an infinitely variable gear having a primary pulley mounted on a primary shaft, a secondary pulley mounted on a secondary shaft and a belt passed around the primary and secondary pulleys;
• and a reduction gear having reduction gears mounted on a reduction gear shaft, these components being housed in a transmission casing, wherein
• said transmission casing comprises a torque converter housing portion in which the torque converter is housed and an infinitely variable gear housing portion which is formed separately from the torque convertor housing portion and in which the infinitely variable gear is housed, said forward-reverse switching mechanism is provided between the torque convertor and the primary shaft of the infinitely variable gear and is supported on a support portion integrally-formed in the torque converter housing portion, opposite ends of the primary shaft of the infinitely variable gear are supported on support portions respectively integrally-formed in the infinitely variable gear housing portion and the torque convertor housing portion, and opposite ends of the secondary shaft of the infinitely variable gear are supported on support portions respectively integrally-formed in the infinitely variable gear housing portion and the torque convertor housing portion.