Abstract: A device and method are provided for automatically adjusting torque transmitting ability of a hydrodynamic coupling in a transmission arranged between a power turbine and a crank shaft in a turbocompound combustion engine. The method includes continuously registering a value for one or several of: a. engine load parameter for the combustion engine and/or, b. temperature in the combustion engine and/or, c. parameters for indicating NVH in the transmission; If parameters a to c have passed a predetermined value for each of the parameters, then braking a power turbine side of the hydrodynamic coupling and continuously adjusting said torque transmitting ability of the hydrodynamic coupling in dependence of the development of the parameters a to c. Increased control of the transmission and engine performance, especially lower noise and exhaust emissions, and accelerated heating of the engine during cold starts, but also better auxiliary braking, can be provided.

Abstract: The present invention relates to a gear system with automatic operation designed to transmit the torque from the engine of an automotive vehicle to the driven wheels of the vehicle, in which changes in the vehicle speed is controlled as a function of the torque generated by the engine and of the inertial momentum of the vehicle.

Abstract: In an automatic transmission controller, a gear shift control unit has a target rotational angle position calculator for calculating a target rotational angle position of a gear shift motor, an actual rotational angle position calculator for calculating the actual rotational angle position of the gear shift motor, and an F/B gain setting unit. When a gear shift instruction from a gear shift controller is a gear shift pattern for driving at least a select motor, the F/B gain is set to be larger that of the gear shift pattern in which the select motor is not driven, and also a motor driving mode and a motor braking mode are switched to each other in accordance with the difference between the target rotational angle position and the actual rotational angle position.

Abstract: Transmission system, in which a single double-effect actuator, used to engage/release the gears, comprises a piston which is mobile with reciprocating motion, and has different areas which face first and second chambers of the actuator. The first and second chambers are supplied respectively, directly by a source of pressurised fluid, and by a valve of the proportional type, which is interposed between the source of pressurised fluid and the actuator.

Abstract: A transmission unit for drive units is used to achieve at least two operational states: a first operational state for the transmission of power with at least two gear steps, and a second operational state for braking. The transmission unit includes an input shaft and an output shaft, a hydraulic transmission part and a mechanical transmission part. The two transmission parts are arranged in series. The hydraulic part includes at least two blade wheels in the form of a primary blade wheel and a secondary blade wheel, which together form at least one toroid operating space which can be filled with operating fluid. The two blade wheels are coupled to the input shaft of the transmission unit and to the mechanical part via at least part of the first operational state in such a way that power is transmitted from the primary blade wheel to the mechanical part via the secondary blade wheel.

Abstract: A powertrain for passenger cars includes a high specific output engine coupled to an automatic transmission which is expanded from four to five forward speed ratios by a novel two-speed torque converter assembly within the transmission. Both of hydrodynamic action and an integral planetary gearset contribute to torque multiplication provided by the high-stall-speed torque converter when it is in its lower speed ratio, and engagement of a lockup clutch simultaneously deactivates both sources of torque multiplication to thereby establish a 100% efficient one-to-one speed ratio across the converter. Also included in the powertrain in a control system which secures high transmission efficiency early during vehicle acceleration by employing lockup of the torque converter as the first of the four upshifts for the five-speed transmission.