Patent ID: 7032552

Claim:
A device for releasably connecting and adjusting a camshaft ( 3 , 3 ′) and a crankshaft of an internal combustion engine, comprising an adjusting gear ( 1 , 1 ′) formed as a three shaft transmission, which has a drive shaft ( 4 , 4 ′) connected with the crankshaft, an output shaft ( 5 , 5 ′) connected with the camshaft, and an adjusting shaft ( 6 , 6 ′) connected with an electric adjusting motor ( 2 , 2 ′), a gear transmission ratio i o is defined between the drive shaft and the output shaft ( 4 , 4 ′; 5 , 5 ′) when the adjusting shaft ( 6 , 6 ′) is at rest, and a magnitude of the gear transmission ratio is determined by a gear type and a direction of setting of camshaft ( 3 , 3 ′), which has a base or emergency running position, wherein upon a failure of the adjusting motor ( 2 , 2 ′) or a controlling system, the base or emergency running position of camshaft ( 3 , 3 ′) can be reached and maintained by one of braking or setting the adjusting shaft ( 6 , 6 ′), and rotation of drive shaft ( 4 , 4 ′), as well as the gear transmission ratio i o ; wherein for a late adjustment of camshaft ( 3 , 3 ′) a minus gear with i o <0 or a plus gear with i o >1 is provided, and for an early adjustment of camshaft ( 3 , 3 ′) a plus gear with 0<i o <1 is provided; wherein the adjusting motor ( 2 ) includes a rotor ( 8 ) and a stator fixedly connected to a cylinder head, the rotor ( 8 ) includes a permanent magnet, and for a power free setting of the adjusting shaft ( 6 ) a holding torque of the adjusting motor is utilized; and at least a provisional functioning of the internal combustion engine is possible by a corresponding setting of the adjusting motor ( 2 ) and through increasing of the holding torque by a changed friction moment of adjusting gear ( 1 ) from 60% to 100% of the changed, maximum, dynamic camshaft torque, which reacts upon the adjusting shaft ( 6 ), when starting and with low idle speed.