A continuously variable transmission for a vehicle propulsion system includes a controller including an instruction set, the instruction set executable to determine whether a current inertia torque value is greater than a previous inertia torque value, execute control over one of a first clamp pressure and a second clamp pressure such that one of the first clamp pressure and the second clamp pressure corresponds to a current inertia torque value if the current inertia torque value is greater than a previous inertia torque value, and execute control over one of the first clamp pressure and the second clamp pressure such that said one of the first clamp pressure and the second clamp pressure corresponds to previous inertia torque value if the current inertia torque value is not greater than a previous inertia torque value for a predetermined period of time.

A powertrain system includes a torque generating device to transfer torque to a driveline via a CVT, wherein the CVT includes a first pulley coupled to a second pulley via a flexible continuous device to transfer torque therebetween. A controller including a processor and memory is operatively connected to the CVT. The controller includes an instruction set that is executable to dynamically monitor operating parameters associated with an input force and an output force of the CVT and determine an amplitude variation of one of the operating parameters. The controller is disposed to detect an impending slip event based upon the amplitude variation, wherein the impending slip event is associated with a macro-slip condition on the flexible continuous device. Operation of the CVT is controlled to preclude the impending slip event.

A powertrain system includes a torque generating device to transfer torque to a driveline via a CVT, wherein the CVT includes a first pulley coupled to a second pulley via a flexible continuous device to transfer torque therebetween. A controller including a processor and memory is operatively connected to the CVT. The controller includes an instruction set that is executable to dynamically monitor operating parameters associated with an input force and an output force of the CVT and determine an amplitude variation of one of the operating parameters. The controller is disposed to detect an impending slip event based upon the amplitude variation, wherein the impending slip event is associated with a macro-slip condition on the flexible continuous device. Operation of the CVT is controlled to preclude the impending slip event.

A control device for a continuously variable transmission of a vehicle includes: a shift control section being configured to perform a rough road corresponding control to increase the hydraulic pressure supplied to the secondary pulley to a value larger than the hydraulic pressure at a smooth road judgment at which the smooth road is judged, at a rough road judgment at which the rough road is judged, and thereby to increase the clamping force of the secondary pulley with respect to the circular belt member; and a rotation speed control section being configured to control the transmission gear ratio at the rough road judgment so that a rotation speed of the primary pulley becomes equal to or greater than a lower limit rotation speed which is previously set.

A hydraulic pressure controller includes belt sandwiching force increasing means. The belt sandwiching force increasing means increases a belt sandwiching force by a primary pulley and a secondary pulley on the basis of a braking force request from a driver, up to a predetermined value to prevent a belt from slipping due to a braking force. The belt sandwiching force increasing means increases the belt sandwiching force in a range of less than the predetermined value before the braking force request occurs.

A flexible binary pump system for a motor vehicle transmission includes a shaft, a first vane pump mounted on the shaft and having a first rotor with a first diameter and a first width and a second vane pump mounted on the shaft and having a second rotor with a second diameter and a second width. The first vane pump provides hydraulic fluid to the transmission at a first pressure, and the second vane pump provides hydraulic fluid to the transmission at a second pressure. The first diameter, first width, second diameter, and second width are selected to optimize power consumption of the binary pump system and hydraulic fluid budget for the transmission.