Shift control of continuously-variable transmission

A continuously-variable transmission shift control apparatus comprising:

• a toroidal continuously-variable transmission including a toroidal transmission unit including a power roller disposed between an input disk and an output disk, and a trunnion supporting the power roller;
• a shift actuating section to incline the power roller by offsetting the trunnion to achieve a shift control of the toroidal continuously-variable transmission in response to a control command;
• means for determining a target transmission ratio, and an actual transmission ratio of the toroidal continuously-variable transmission;
• means for controlling the actual transmission ratio toward the target transmission ratio by producing the control command in one selected, from a forward traveling control mode, and a reverse traveling control mode, in accordance with a first parameter representing a driver's intention;
• and
• means for detecting a change of a vehicle traveling direction in accordance with a second parameter, and to modify the shift control of the toroidal continuously-variable transmission so as to shift the actual transmission ratio to a speed decreasing side upon detection of the change of the vehicle traveling direction.

A continuously-variable transmission shift control apparatus comprising:

• a toroidal continuously-variable transmission including a toroidal transmission unit including a power roller disposed between an input disk and an output disk, and a trunnion supporting the power roller;
• a shift actuating section to incline the power roller by offsetting the trunnion to achieve a shift control of the toroidal continuously-variable transmission in response to a control command;
• a target transmission ratio setting section to set a target transmission ratio;
• a transmission ratio sensing section ascertaining an actual transmission ratio of the toroidal continuously-variable transmission;
• a controlling section to control the actual transmission ratio toward the target transmission ratio by producing the control command in one of a forward traveling control mode for a forward vehicle traveling state, and a reverse traveling control mode for a reverse vehicle traveling state;
• and
• a control modifying section to select one of the forward traveling control mode and the reverse traveling control mode in accordance with a first parameter representing a driver's intention, to detect a change of a vehicle traveling direction in accordance with a second parameter which includes a vehicle speed, and to modify the shift control of the toroidal continuously-variable transmission so as to shift the actual transmission ratio to a speed decreasing side upon detection of the change of the vehicle traveling direction.

A shift control process for a toroidal continuously-variable transmission, comprising:

• setting a target transmission ratio;
• ascertaining an actual transmission ratio of the toroidal continuously-variable transmission;
• controlling the actual transmission ratio toward the target transmission ratio in one of a forward traveling control mode for a forward vehicle traveling state, and a reverse traveling control mode for a reverse vehicle traveling state;
• selecting one of the forward traveling control mode and the reverse traveling control mode in accordance with a first parameter representing a driver's intention;
• detecting a change of a vehicle traveling direction in accordance with a second parameter which is the actual transmission ratio;
• and
• modifying the shift control of the toroidal continuously-variable transmission so as to shift the actual transmission ratio to a speed decreasing side upon detection of the change of the vehicle traveling direction.