The invention relates to a method for synchronising the common speed (ω p) of two concentric primary shafts (1, 6) of a hybrid transmission in a hybrid operating mode wherein said two shafts are rotatably connected by a first coupling means (5), with the speed (ω s) of a secondary transmission shaft (10) comprising at least one idler pinion for allowing the coupling of one of said pinions (11, 12) to the shaft (10) thereof by closing a second coupling means (13) that does not have mechanical synchronisation bodies, the torque (Te) of the electric machine being temporarily reduced during the synchronisation phase in order to meet the conditions of a perfect coupling when the value thereof caps at an upper limit value (T.sub.e.sup.max) or a lower limit value (T.sub.e.sup.min).

Systems and methods for improving shifting of a manual transmission coupled to an engine are presented. In one example, a load provided to the engine is increased in response to a transmission gear upshift so that engine speed may be quickly decreased to synchronize with transmission input speed, thereby allowing quicker manual transmission gear shifts.

A transmission for a vehicle having a prime mover with an output shaft. The transmission includes an offgoing clutch that is selectively connected to the output shaft, and a controller in communication with the prime mover. The controller includes an offgoing clutch control module that determines an offgoing clutch torque profile at the start of a torque phase in a power downshift that does not exceed a predetermined offgoing clutch energy threshold and a torque request module that limits a rate of input torque into the transmission from the prime mover based upon the determined offgoing clutch torque profile.

The present invention relates to a hybrid powertrain and method of controlling same, the hybrid powertrain comprising an internal combustion engine; a gearbox with an input and an output shaft; a range gearbox connected to the output shaft; a first planetary gear connected to the input shaft; a second planetary gear connected to the first planetary gear; a first electrical machine connected to the first planetary gear; a second electrical machine connected to the second planetary gear; one gear pair connected with the first planetary gear and the output shaft; and one gear pair connected with the second planetary gear and the output shaft, wherein the internal combustion engine is connected with the first planetary gear via the input shaft. The range gearbox comprises a third planetary gear with a third sun wheel and a third planetary wheel carrier and a fourth clutch device arranged to connect and disconnect the third sun wheel with/from the third planetary wheel carrier.

A method is provided for calibrating a control algorithin of a clutch control unit of a vehicle. The method includes requesting, clutch disengagement, or engagement, monitoring clutch actuator position, determining a time interval that starts with the clutch disengagement or engagement request and ends when the clutch actuator has reached a predetermined position, and calibrating an estimated time interval of the control algorithm starting with clutch disengagement or engagement bequest and when the clutch actuator has reached a predetermined position based on the determined time interval. A computer program for implementing the method, as well as a vehicle comprising a clutch control unit calibrated according to the method, are also provided.

A method is provided to control a hybrid powertrain comprising an internal combustion engine; a gearbox with input and output shafts; a range gearbox, connected to the output shaft; a first planetary gear, connected to the input shaft; a second planetary gear, connected to the first planetary gear; a first electrical machine, connected to the first planetary gear; a second electrical machine, connected to the second planetary gear; at least one gear pair, connected with the first planetary gear and the output shaft; and at least one gear pair, connected with the second planetary gear and the output shaft, wherein the internal combustion engine is connected with the first planetary gear via the input shaft. The method comprises the steps: a) engaging a gear by way of connecting two rotatable components in the first planetary gear; b) connecting the at least one gear pair, connected with the second planetary gear and the output shaft; c) connecting a sixth gear pair, arranged between a countershaft and the range gearbox with the countershaft, so that the countershaft is connected with the output shaft via the range gearbox; d) controlling the range gearbox from a low range position to a neutral state, in which no torque transmission occurs through the range gearbox; e) controlling two rotatable components in the range gearbox towards achieving a synchronized rotational speed with the assistance of the first electrical machine; f) connecting the rotatable components with the use of a shiftable third clutch device; and g) engaging a gear by way of connecting two rotatable components in the second planetary gear.

A method is provided to control a hybrid powertrain comprising an internal combustion engine; a gearbox with input and output shafts; a range gearbox connected to the output shaft; a first planetary gear, connected to the input shaft; a second planetary gear, connected to the first planetary gear; first and second electrical machines, respectivley connected to the first and second planetary gears; a gear pair connected with the first planetary gear and the output shaft; and a gear pair, connected with the second planetary gear and the output shaft, wherein the internal combustion engine is connected to the input shaft. The method comprises: a) engaging a gear by connecting two rotatable components in the first planetary gear; b) connecting the second or the fourth gear pair; c) connecting a sixth gear pair, arranged between a countershaft and the range gearbox to the countershaft, so that the countershaft is connected with the output shaft via the range gearbox; d) synchronising the rotational speed between two rotatable components in the range gearbox; e) connecting the rotatable components with a shiftable third clutch device; and f) engaging a gear by way of connecting two rotatable components in the second planetary gear.

A method and apparatus for continually and rapidly adjusting the output torque of an engine according to a torque demand uses an active tappet to vary the instant air charge in a combustion chamber, so as to modulate engine torque during an automatic change of speed ratio. The invention allows substantially efficient combustion throughout the engine operating map. Various methods of changing the charge of air are disclosed.

A method of controlling a Continuously Variable Transmission (CVT) simulates a step-ratio transmission upshift. To simulate a step-ratio torque phase, the input torque is gradually reduced before beginning to change the variator ratio. Then, as the variator ratio is changed, the input torque is gradually increased to compensate for the decreasing torque ratio, simulating the relatively constant output torque of an inertia phase of a step-ratio upshift.

A method for propulsion of a vehicle (100) having a combustion engine (101) and a gearbox (103), the engine (101) having a combustion chamber with an inlet for supply of combustion gas and an outlet for evacuation of exhaust gas, the method includes, during a change of gear from a first higher to a second lower gear ratio, increasing the pressure (P.sub.ut) at the chamber outlet (202) with a turbocharger unit and, when the rate of revolution (n) of the combustion engine (101) has at least partially fallen, controlling the turbocharger unit (203) such that the combustion gas pressure (P.sub.in) is increased.