A control system for a transmission reverser, which includes an output shaft, an output gear, a reverse gear, a forward clutch, an input power clutch, a first reverse disconnect device, and a second reverse disconnect device, has one or more controllers with processing and memory architecture configured to execute control logic to control the transmission reverser in a start-up mode, a forward mode and a reverse mode. In the start-up mode, the one or more controllers command the input power clutch and the first reverse disconnect device to simultaneously engage momentarily to apply an engagement torque to the second reverse disconnect device.

A method of controlling a continuously variable electric drivetrain (CVED) including a high ratio traction drive transmission and at least one of a first motor-generator and a second motor-generator is disclosed. The method includes the steps of receiving a an output speed, determining a kinematic output speed, and determining a slip state of the high ratio traction drive transmission based on a comparison of the output speed to the kinematic output speed.

In a control device of a vehicle power transmission device, a first meshing clutch has a drive power source side meshing member coupled to a power transmission member, an auxiliary drive wheel side meshing member coupled to the power transmission member, and an actuator engaging or releasing the drive power source side meshing member and the auxiliary drive wheel side meshing member, and when a rotation speed difference between a rotation speed of the drive power source side meshing member and a rotation speed of the auxiliary drive wheel side meshing member is larger than a predefined value at the time when a first meshing clutch is brought into an engaged state, a clamping pressure on a transmission belt is increased as compared to when a rotation speed difference is equal to or less than a predefined value.

A method for operating a multi-clutch transmission for a motor vehicle, having at least the following steps: a) closing a first clutch of the multi-clutch transmission, in order to transfer an input torque (M_k1) between a drive machine of the motor vehicle and at least one first sub-transmission of the multi-clutch transmission; b) applying a drag torque (M_k2) to a second sub-transmission of the multi-clutch transmission, which is coupled to the first sub-transmission, via a second clutch of the multi-clutch transmission; c) detecting a clutch slip of the second clutch, which is dependent on the drag torque (M_k2); and d) determining a current gear selection of the multi-clutch transmission by evaluating the clutch slip. The disclosure further relates to a multi-clutch transmission and to a motor vehicle having a multi-clutch transmission.

A transmission includes at least one shift element for which both the apply pressure and the release pressure are actively controlled. A controller adjusts the torque capacity of the shift element by varying the apply pressure and the release pressure in a coordinated fashion. During particular events, such as a shift event with the shift element as oncoming element or holding element, both the apply pressure and the release pressure are monotonically increased, mitigating the effect of hysteresis.

A method for controlling a pulley of a vehicle having a continuously variable transmission may include: determining, by a controller, a pulley target torque and a target pulley ratio, upon detecting disturbance of the vehicle; determining, by the controller, target pressures of a driving pulley and a driven pulley based on the pulley target torque and the target pulley ratio and comparing the target pressures with each other; and controlling, by the controller, a pressure of a pulley having a larger target pressure in the comparing to be a maximum pressure generatable depending on a traveling situation of the vehicle and controlling a pressure of the other pulley to be increased to a correction pressure for implementing the target pulley ratio.

Systems and methods for controlling transmissions having CVTs are disclosed with multiple modes and gearing arrangements for range enhancements, where embodiments include synchronous shifting to allow the transmission to achieve a continuous range of transmission ratios, while minimizing empty cycling of the CVT during mode shifts. Embodiments provide for wide ratio range and performance and efficiency flexibility, while maximizing CVT usage through synchronous shifting.

A continuously variable transmission (CVT) comprises a shaft rotatable about an axis, and variator assembly, and an actuator mechanism. The variator assembly includes a pulley supported on the shaft and having a ramp surface, and an endless rotatable device frictionally engaged with the pulley. The ramp surface inclines in an axial direction along the axis toward the endless rotatable device. The CVT further comprises an actuator mechanism that includes a wedge component that has a wedge surface interfacing with the ramp surface, and a rotary piston operatively connected to the wedge component. The rotary piston defines a first fluid chamber pressurizable to apply a rotational force that provides relative motion between the ramp surface and the wedge surface resulting in a wedge force on the ramp surface and a clamping force of the endless rotatable device on the pulley.

A method of controlling a continuously variable transmission includes monitoring powertrain operating conditions, and calculating, via an electronic controller, a commanded clamping force based on the powertrain operating conditions, wherein the commanded clamping force includes a commanded clamping force of an input pulley and a commanded clamping force of an output pulley on the endless rotatable device. The method also includes activating, via the electronic controller, at least one of the input actuator and the output actuator such that an axial component of the input wedge force and the axial force of the input actuator together provide the commanded clamping force of the input pulley, and an axial component of the output wedge force and the axial force of the output actuator together provide the commanded clamping force of the output pulley.

A hybrid vehicle drive system including an internal combustion engine, a motor-generator, a speed shift mechanism including a first and second frictional engagement mechanisms, a torque limiter interposed the motor generator and the speed shift mechanism in a power transmission path transmitting from the internal combustion engine to an axle, and a controller controlling the speed shift mechanism so as to disengage the first frictional engagement mechanism and engage the second frictional engagement mechanism. The controller is configured to perform controlling the speed shift mechanism so as to increase an engaging force of the second frictional engagement mechanism during switching from high speed stage to low speed stage when an occurrence of slipping is detected than when the occurrence of slipping is not detected.