Abstract: An arrangement and a method for allowing disengagement of a gear of a gearbox in a vehicle. A clutch provides elastic rotation when driving torque is transmitted in the driveline. A first sensor detects the position (P1) of a first component of a driveline which is situated before the clutch and a second sensor detects the position (P2) of a second component of the driveline which is situated after the clutch. A control unit stores at least one measured value which is related to a mutual angle (AREF) between the first component and the second component when a gear is engaged in the gearbox, and initiates an engine control action such that the mutual angle (AREF) between the first component and the second component is rectified before the gear is disengaged.

Abstract: The invention relates to a device for controlling a braking arrangement on a heavy vehicle. The braking arrangement comprises a main brake, which includes braking devices (1a -f), for example disc brakes, that are each arranged to act on one of the vehicle wheels (2a-f). Furthermore, the braking arrangement comprises at least one auxiliary brake (3) and a brake control (10) with which the named main brake (1a-f) and auxiliary brake (3) are activated. When a driver activates the brake control (10), a control unit (9) in the arrangement is arranged to initiate activation of the main brakes (1a-f) and the auxiliary brake (3) and thus distributes the braking effect between these brakes in such a way that the braking effect requested by the driver is obtained in the shortest possible time and in such a way that the use of the brake devices (1a-f) of the main brake is minimised after an initial period. The invention relates to a braking system for a heavy vehicle, which comprises an arrangement described above.

Abstract: A device for controlling the drive of a vehicle, incorporating control means (1, 5, 6) which in a first operating state are arranged to control the vehicle so that the vehicle maintains a substantially constant speed and in a second operating state to control vehicle so that it accelerates. The device also incorporates an element (1, 2) which in the second operating state is arranged to make it possible to set any desired substantially constant acceleration of the vehicle.

Abstract: The invention relates to an improved method and arrangement for implementing that method, for obtaining in motor vehicles with mechanical stepped gearboxes with automatic gear changing a gentle and quiet engine adjustment during downshifts in normal operating situations and automatically in operating situations where a need for quicker downshifts requires quicker engine synchronisation. In normal operating situations, downshifts involve using only a limited fuel quantity, preferably corresponding to 20% of full-load fuel quantity, in order to raise the engine speed to the synchronous speed for the next gear, resulting in quieter engine adjustment without the occurrence of obvious disturbance of comfort, risk of losing downshifts or safety disadvantages.

Abstract: The invention relates to an improved method for ensuring that at the time of disengagement of a gear in connection with changing gear in mechanical gearboxes without clutch disengagement the engine torque is adjusted to a zero-torque level which is continuously corrected on the basis of the instantaneous acceleration of the engine but also on the basis of the internal friction of the engine and on the basis of any power take-offs being powered by the engine.In gear changing, adjustment begins with a torque reduction at time t.sub.1. The torque is reduced to a zero-torque level M.sub.0 which is continuously variable during the reduction and which is adapted to the current engine deceleration and which is corrected by a friction factor M.sub.f and an acceleration factor M.sub.a. The friction factor M.sub.f is derived from a matrix M.sub.f (n,T) on the basis of current engine speed n and engine temperature T, and the acceleration factor M.sub.

Abstract: A transmission for a vehicle comprises a mechanical stepped gearbox (6) in front of which a hydraulic torque converter (5) is arranged. The torque converter (5) comprises a turbine wheel (19) which is connected to a turbine shaft (21). An input shaft (25) of the gearbox (6) is connected in a drive power-transmitting manner to the turbine shaft (21). In addition, a brake (34) is connected to the turbine shaft (21) or the input shaft (25), in which respect, on starting-up, the input shaft (25) can be stopped in order to permit engagement of a starting gear without the need to produce drive power interruption by means of a conventional clutch. The brake (34) is also used when changing-up for synchronization of the gearbox (6) together with an electrical control unit (32) for engine regulation. This allows the gear-changing in a mechanical, unsynchronized stepped gearbox to be carried out in a simple manner.

Abstract: A method and apparatus for controlling the speed of a motor vehicle in which a target speed is established and lowered upon each actuation of a driver-actuated brake. If the actual vehicle's speed exceeds the target speed, an auxiliary braking system is actuated to lower the actual vehicle speed to the target speed. If the vehicle's accelerator is thereafter actuated, the auxiliary braking system is disabled until the driver-actuated brake is again actuated.