CONTINUOUSLY VARIABLE TRANSMISSION

PURPOSE:To improve the efficiency, the capacity and the ability by employing a differential gear device which is excellent in the power transmission efficiency and capable of selecting a wide variable transmission range by changing the combination of the tooth number to incorporate the control function of the fluid such as the hydraulic pressure suitable for the variable transmission function. CONSTITUTION:A rotary cylinder part (b) is incorporated in a member equivalent to an arm to restrict a planet gear 4 of a differential gear mechanism part (a), a shaft 8 on one side of a pair of sun gears 3, 6 is made an input shaft of the cylinder part (b), the number of rotation of the shaft is changed by controlling the movement of the fluid to be generated in the rotary cylinder, and the change of the relative number of rotation of the output shaft of the interlocking system is taken out as the output of the variable transmission. The rotary cylinder incorporated in the device is constituted of a rotor 11 of circular section similar to a housing 9 of circular section, and a fixed seal 12 is provided on one side and a rotary seal 10 is provided on the other side to form a pressure chamber, and the phase of the partition wall is changed as the rotor 11 is rotated to switch the pressure chamber successively.