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AssigneeVolvo Lastvagnar AB
InventorsLars Gunnar Karlsson, Jan Erik Lauri, Karl Marcus Steén
Estimating the term…
Drive unit for motor vehicles, comprising an engine and an automated friction clutch arranged between the engine and its gearbox, the engagement and disengagement of the clutch being controlled by a servo unit, which is controlled by a control computer to which, from various sensors there are fed values of engine speed, rotational speed of the input shaft of the gearbox, the position of the servo unit and the position of the gearsift lever. Points on a torque curve are stored in the memory of the control computer, the curve showing the torque as a function of the servo position (the clutch position). The computer is furthermore programmed to calibrate the servo unit to a pulling position, which provides a predetermined desired value of the torque, and to check, with a certain regularity, the actual value of the torque in the pulling position and, if needed, the adjust the actual value towards the desired value by changing the position of the servo unit.
Drive unit for a motor vehicle, comprising:
Method of determining torque transmitted from a motor to the input shaft of a vehicle gearbox via a friction clutch, as a function of the position of a clutch actuator which is controlled by an electronic control unit, to which data is fed on motor rotational speed, the rotational speed of the input shaft and the position of the actuator, wherein the clutch actuator, starting from a disengaged position in which the input shaft is completely disengaged, is set to a first engagement position in which torque is transmitted via the friction clutch to the input shaft, measuring the time from a predetermined lower rotational speed of the input shaft until the input shaft has reached a predetermined higher rotational speed, that the clutch actuator is thereafter, starting from a clutch actuator release position, set at least one other engagement position different from the first engagement position, measuring the time from a predetermined lower rotational speed of the input shaft until the input shaft has reached the same predetermined higher rotational speed, that the torque in said first and second engagement positions is calculated on the basis of the moment of inertia and the angular acceleration of the gearbox masses rotating in the neutral position, and that a torque curve as a function of the clutch actuator position is interpolated and/or extrapolated based on the calculated torque values.
Dependencies are inferred from the claim text.