Continuously variable transmission

A continuously variable transmission comprising:

• a toroidal continuously variable transmission;
• a planetary gear transmission;
• and
• a clutch device comprising:
• a low-speed clutch that is engaged to realize a low-speed mode in which a reduction ratio is increased and is disengaged to realize a high-speed mode in which the reduction ratio is decreased;
• a high-speed clutch that is engaged to realize the high-speed mode and is disengaged to realize the low-speed mode;
• and
• a control unit that switches an engagement/disengagement state of the low-speed clutch and the high-speed clutch so as to realize either of the low-speed mode and the high-speed mode,
• wherein when the mode of the clutch device is switched between the low-speed mode and the high-speed mode, in order to ensure a time period during which both the clutches are kept in engagement concurrently, after one of the low-speed and high-speed clutches which had been in disengagement until then is engaged, the control unit disengages the other of the clutches which had been in engagement until then,
• the control unit estimates a time delay in response which is considered to be necessary from a beginning to an end of the engagement of the one clutch, and
• when switching the speed mode, based on the thus pre-obtained delay time, the control unit starts to engage the one clutch before a transmission ratio of the toroidal continuously variable transmission has reached an optimal value for switching the mode of the clutch device.