Patent ID: 6845740
Filing Date: 2005-01-25
Classification: F01L,Y10T

Abstract:
1. A device for hydraulically adjusting a rotation angle of a camshaft with respect to a crankshaft of an internal combustion engine, the device comprising: a camshaft mountable in a cylinder head of the internal combustion engine, the camshaft having a drive-side end positionable in the cylinder head, wherein the drive-side-end is shaped to define a hydraulic actuating drive controllable as a function of engine operating parameters; the device further comprising: a drive unit drivingly connected to a crankshaft of the engine; an output unit separate from the drive unit, the output unit being connected rotationally fixed to the camshaft; an axial through-bore in the output unit for defining a pressure medium passage; a securing bolt through the through-bore and sized smaller than the through-bore for providing the pressure medium passage past the bolt in the bore; an axially threaded bore in the camshaft toward an end side of the camshaft in which the securing bolt is screwed and held; the output unit having a radially directed, axially, facing end face which faces toward the camshaft and the camshaft having an opposed radially directed, axially facing end side, wherein the end face of the output unit and the end side of the drive side end of the camshaft are non-positively lockable by a prestressing force applied to the output unit and the camshaft to move them together; complementarly molded elements on the end face of the output unit facing the camshaft and the end side of the camshaft facing the output unit and shaped and cooperating for fixing the device to the camshaft in a positive locking manner in the radiall direction; wherein the drive unit is rotatably mounted on the output unit and is connected there to define at least two hydraulic pressure chambers inside the device, the chambers acting against one another such that forces are transmitted via the at least two hydraulic pressure chambers, such that application of hydraulic pressure to the pressure chambers selectively either rotates the output unit or fixes the output unit with respect to the drive unit and correspondingly rotates or fixes the camshaft with respect to the crankshaft; an annular disk having opposite side faces coated to increase frictional force, the disk being disposed between the side face of the output unit facing the camshaft and the end side of the camshaft and in engagement therewith, and the disk cooperating with the securing bolt for reducing the prestressing force of the bolt required for play-free torque transmission from the drive unit to the camshaft; elements on the annular disk enabling detection of whether the disk is present in the device.