Method and apparatus to control continuously variable transmission of motor vehicle

An apparatus for controlling a continuously variable transmission of a motor vehicle that is provided in a power transmission path between a power source that runs the vehicle and at least one drive wheel, wherein a speed ratio of the transmission can be continuously varied, and wherein the speed ratio is defined as a ratio of a rotational speed of an input shaft on a side of the power source to a rotational speed of an output shaft on a side of the at least one drive wheel, the apparatus comprises:

• a controller that:
• controls the speed ratio of the continuously variable transmission in accordance with a predetermined shift condition;
• and
• restricts an upshift of the continuously variable transmission, during an operation of an anti-lock brake system that controls a braking force to prevent the at least one drive wheel from locking during a braking operation.

An apparatus for controlling a continuously variable transmission of a motor vehicle that is provided in a power transmission path between a power source that runs the vehicle and at least one drive wheel, wherein a speed ratio of the continuously variable transmission can be continuously varied, and wherein the speed ratio is defined as a ratio of a rotational speed of an input shaft on a side of the power source to a rotational speed of an output shaft on a side of the at least one drive wheel, the continuously variable transmission comprises a pair of pulleys and a transmission belt that is wound around the pulleys, the transmission belt transmits power between the power source and the at least one drive wheel by using a frictional force, the apparatus comprises:

• a controller that:
• controls the speed ratio of the transmission by hydraulically changing a groove width of each of the pulleys;
• controls a belt clamping force by hydraulically operating at least one of the pulleys to clamp the transmission belt;
• and
• increases an amount of a hydraulic oil delivered from an oil pump when the vehicle is rapidly decelerated and wherein the oil pump generates a hydraulic pressure to control the speed ratio of the transmission and to control the belt clamping force.

A method for controlling a continuously variable transmission of a motor vehicle that is provided in a power transmission path between a power source that runs the vehicle and at least one drive wheel, wherein a speed ratio of the continuously variable transmission can be continuously varied, and wherein the speed ratio is defined as a ratio of a rotational speed of an input shaft on a side of the power source to a rotational speed of an output shaft on a side of the at least one drive wheel, the continuously variable transmission comprises a pair of pulleys and a transmission belt that is wound around the pulleys, the transmission belt transmits power between the power source and the at least one drive wheel by using a frictional force, the method comprises:

• controlling the speed ratio of the transmission by hydraulically changing a groove width of each of the pulleys;
• controlling a belt clamping force by hydraulically operating at least one of the pulleys to clamp the transmission belt;
• and
• increasing an amount of a hydraulic oil delivered from an oil pump when the vehicle is rapidly decelerated and wherein the oil pump generates a hydraulic pressure to control the speed ratio of the transmission and to control the belt clamping force.