Methods, systems, and vehicles that control the temperature of a device included in the vehicle are presented herein. The temperature of the device is controlled by ventilating the device with drivetrain air, such as transmission cooling air. In some embodiments, the device is at a greater temperature than the drivetrain air, which cools the device. In other embodiments, the device is at a lesser temperature than the drivetrain air, which heats the device. The drivetrain air is provided to the device through an exhaust duct coupled to the vehicle's transmission. The drivetrain exhaust air is preferably circulated by the transmission. The transmission may be a continuously variable transmission. The device may be an oxygen sensor that is coupled to an engine exhaust pipe. The oxygen sensor is thermally coupled to the engine exhaust and the engine exhaust pipe, which are at greater temperatures than the transmission exhaust air.

A key pulley segment in a synchronized, segmentally interchanging pulley transmission system is either first or last in a pulley segment set to engage an endless member. The first or last key segment teeth to engage or disengage, respectively, are shortened or completely trimmed, and the adjacent pulley segment to the key segment is elongated such that the inward portion of the tooth profile extends toward the key segment. Shortened tooth or teeth and an elongated adjacent segment together allow for many pulley segments to be designed as key segments. Completely trimmed teeth may be engineered to create a supporting surface for the endless member on the key segment. The elongated adjacent segment may have an extending portion which slidably mates with the supporting surface of the key segment, thereby receiving radial support therefrom. Multiple pulley segments from different pulley segment sets may be connected or constructed to move together in a unified stack, and may be staggered such that any one segment may be in an engaging position with the endless member when the unified stack is moved along the axis of rotation. Unified stacks may have guiding rails on both inner and outer radial surfaces, and the pulley assembly may have mating features that receive such guiding rails. Any number of the pulley segments in a unified stack may be key pulley segments. Pulley segments of a stack may be vertically separated into one or more unified stacks. Unified stacks may be moved by way of a cam or roller cam system, where each unified stack has a slidably or ratably attached roller and roller-arm. Chassis-mounted cams engage the rollers outside of the contact zone, rollers and roller-arms are moved into and out of engagement with the cams, and individual segments of a unified stack are moved into or out of engagement. Rollers may be actuated into and out of engagement by electromagnets, fixable mounted in an array. Rollers may discretely engage with multiple cams, by way of several electromagnet-arrays, and thereby complete several stack axial motions. Electromagnets in an array may be selectively energized to move selected rollers to an active position in order to effect key pulley segment engagement, stack axial movement and transition.

A key pulley segment in a synchronized, segmentally interchanging pulley transmission system is either first or last in a pulley segment set to engage an endless member. The first or last key segment teeth to engage or disengage, respectively, are shortened or completely trimmed, and the adjacent pulley segment to the key segment is elongated such that the inward portion of the tooth profile extends toward the key segment. Shortened tooth or teeth and an elongated adjacent segment together allow for many pulley segments to be designed as key segments. Completely trimmed teeth may be engineered to create a supporting surface for the endless member on the key segment. The elongated adjacent segment may have an extending portion which slidably mates with the supporting surface of the key segment, thereby receiving radial support therefrom. Multiple pulley segments from different pulley segment sets may be connected or constructed to move together in a unified stack, and may be staggered such that any one segment may be in an engaging position with the endless member when the unified stack is moved along the axis of rotation. Unified stacks may have guiding rails on both inner and outer radial surfaces, and the pulley assembly may have mating features that receive such guiding rails. Any number of the pulley segments in a unified stack may be key pulley segments. Pulley segments of a stack may be vertically separated into one or more unified stacks. Unified stacks may be moved by way of a cam or roller cam system, where each unified stack has a slidably or ratably attached roller and roller-arm. Chassis-mounted cams engage the rollers outside of the contact zone, rollers and roller-arms are moved into and out of engagement with the cams, and individual segments of a unified stack are moved into or out of engagement. Rollers may be actuated into and out of engagement by electromagnets, fixable mounted in an array. Rollers may discretely engage with multiple cams, by way of several electromagnet-arrays, and thereby complete several stack axial motions. Electromagnets in an array may be selectively energized to move selected rollers to an active position in order to effect key pulley segment engagement, stack axial movement and transition.

Control system for a continuously variable transmission with a first and a second pair of conical sheaves each with adjustable running radius, in which of each pair at least one sheave (14a, 14b) is coupled to a first and a second hydraulic actuator (20a, 20b) respectively which sets the axial sheave position in dependence of the amount of hydraulic medium supplied thereto, in which the actuators are connected with means to supply and discharge thereto/therefrom respectively, hydraulic medium, and one actuator is connected to a source of hydraulic pressure medium, and in which furthermore the first and second actuator respectively is connected with a first and second control chamber (60, 124) respectively, filled with hydraulic medium and having a variable control volume, in such a way that an increase of the first control volume is coupled to a decrease of the second control volume, and vice versa.

A continuously variable transmission with an annular band body including grooves meshable with movable teeth provided on a second pulley and a biasing unit configured to bias the movable teeth radially outwardly of a shaft portion is provided with a hydraulic control unit configured to reduce a hydraulic pressure in a second oil chamber when a speed ratio reaches a predetermined speed ratio at which the grooves are meshed with the movable teeth.

A continuously variable transmission with an annular band body including grooves meshable with movable teeth provided on a second pulley and a biasing unit configured to bias the movable teeth radially outwardly of a shaft portion is provided with a hydraulic control unit configured to reduce a hydraulic pressure in a second oil chamber when a speed ratio reaches a predetermined speed ratio at which the grooves are meshed with the movable teeth.

A conical pulley for belt Continuously-Variable-Transmissions allowing a bigger than the width W of the belt maximum axial displacement of the one conical pulley half relative to the other, achieving a bigger than 0.5*W*tan(F) difference between the maximum and the minimum effective radiuses of the belt as it runs on the pulley, wherein F is the angle of the working conical surfaces of the pulley, providing a substantial increase of the transmission gear ratio range that enables faster accelerations at the low gear ratios and better mileage and quieter operation at the high gear ratios.

A conical pulley for belt Continuously-Variable-Transmissions allowing a bigger than the width W of the belt maximum axial displacement of the one conical pulley half relative to the other, achieving a bigger than 0.5*W*tan(F) difference between the maximum and the minimum effective radiuses of the belt as it runs on the pulley, wherein F is the angle of the working conical surfaces of the pulley, providing a substantial increase of the transmission gear ratio range that enables faster accelerations at the low gear ratios and better mileage and quieter operation at the high gear ratios.

A continuously variable transmission includes an input pulley (1) in which a pair of pulley halves (4) with pulley faces (4a) form a V-groove (6), an input shaft (2) which journals the input pulley (1), and an endless transmission member (5) wound on the input pulley (1). One of the pulley halves (4) of the input pulley (1) has a piston part (16) relatively rotatable with respect to the input shaft (2) and a pulley half disc (13) slidable on the surface of the piston part (16) through the intermediary of a friction reducing part (11) between the piston part (16) and the endless transmission member (5). The pulley half disc (13) is splined to and integrally rotated with the input shaft (2).

A continuously variable transmission includes an input pulley (1) in which a pair of pulley halves (4) with pulley faces (4a) form a V-groove (6), an input shaft (2) which journals the input pulley (1), and an endless transmission member (5) wound on the input pulley (1). One of the pulley halves (4) of the input pulley (1) has a piston part (16) relatively rotatable with respect to the input shaft (2) and a pulley half disc (13) slidable on the surface of the piston part (16) through the intermediary of a friction reducing part (11) between the piston part (16) and the endless transmission member (5). The pulley half disc (13) is splined to and integrally rotated with the input shaft (2).