Abstract: Method and arrangement for regulating the rotational speed of a crankshaft included in an internal combustion engine during a gear changing process of a gearbox connected to the internal combustion engine. The arrangement includes a compressor mounted in connection with the air inlet of the internal combustion engine. A transmission having a variable gear ratio is located between the crankshaft and a driving shaft arranged in connection with the compressor, and a control means is arranged to control the gear ratio between the crankshaft and the compressor. When changing from a higher to lower gear, the control means is arranged to control the gear ratio between crankshaft and compressor so that the gear ratio between these components is reduced, and wherein moment of inertia is transferred from compressor to crankshaft resulting in an acceleration of the crankshaft.

Abstract: An engine brake application system for an internal combustion engine. The engine has at least one cylinder, at least one exhaust valve associated with the cylinder, and a rocker arm for activating the exhaust valve. The rocker arm is arranged on a hollow rocker shaft having a regulator responsive to an increase in oil pressured in the hollow rocker arm shaft and incorporated into the rocker arm for taking up clearance between the rocker arm ant the exhaust valve. To effect a reduction of engine speed during a gear shift, the system includes an actuator responsive to a signal generated in response to a need to effect a gear shift for rapidly increasing the oil pressure in the hollow rocker arm shaft to thereby effect valve clearance take-up.

Abstract: An engine brake application system for an internal combustion engine. The engine has at least one cylinder, at least one exhaust valve associated with the cylinder, and a rocker arm for activating the exhaust valve. The rocker arm is arranged on a hollow rocker means responsive to an increase in oil pressured in the hollow rocker arm shaft and incorporated into the rocker arm for taking up clearance between the rocker arm and the exhaust valve. To effect a reduction of engine speed during a gear shift, the system includes means responsive to a signal generated in response to a need to effect a gear shift for rapidly increasing the oil pressure in the hollow rocker arm shaft to thereby effect valve clearance take-up.