Patent ID: 6849020

Claim:
A continuously variable power-split transmission comprising: an input shaft which is driven by an engine; an output shaft; a first differential gear mechanism which comprises a first rotating member connected to the input shaft, a second rotating member, and a third rotating member, and which distributes the rotation of the first rotating member between the second rotating member and the third rotating member; a countershaft; a toroidal variator and a first power transmission mechanism which are connected in series for transmitting rotation between the second rotating member and the countershaft, the toroidal variator comprising an input disk, an output disk, and a power roller which is gripped between the input disk and output disk by a thrusting force corresponding to the rotational torque of the second rotating member, and the first power transmission mechanism transmitting rotation between the output disk and the countershaft; a second power transmission mechanism for transmitting the rotation of the third rotation member to the countershaft; and a clutch device for selectively transmitting the rotation of the countershaft and the rotation of the input disk to the output shaft; wherein a reduction ratio R 1 relating to the transmission of rotation by the first transmission mechanism from the output disk to the countershaft, a reduction ratio R 2 of the second power transmission mechanism, and a speed ratio α 1 of the third rotating member and the second rotating member are set to values at which, in a state where the clutch device is transmitting the rotation of the input disk to the output shaft, the rotational torque of the second rotating member does not fall below the rotational torque which is transmitted from the first power transmission unit to the output disk.