Camshaft arrangement

Abstract

A camshaft arrangement ( 1 ) for changing the relative angle of at least one first cam of a camshaft ( 2 ) relative to a second cam of the camshaft ( 2 ), wherein the arrangement includes an angle adjusting device ( 3 ) having a stator ( 4 ) and a rotor ( 5 ) rotatably disposed relative to said stator, wherein the rotor ( 5 ) is rotationally fixed to a shaft ( 6 ), wherein the stator ( 4 ) is rotationally fixed to a hollow shaft ( 7 ), wherein the shaft ( 6 ) and the hollow shaft ( 7 ) are disposed concentric to each other, wherein the at least one first cam is rotationally fixed to the shaft ( 6 ), wherein the at least one second cam is rotationally fixed to the hollow shaft ( 7 ), and wherein the rotationally fixed connection between the rotor ( 5 ) and the shaft ( 6 ) is produced by at least one screw ( 8 ). In order to establish a fixed connection between the rotor and the shaft, taking up little space, according to the invention, the shaft ( 6 ) having an end face ( 9 ) contacts a contact surface ( 10 ) of the rotor ( 5 ) and is pulled against the contact surface ( 10 ) by the at least one screw ( 8 ), and the shaft ( 6 ) has a cross-sectional area (A 1 ) along the axial extent thereof present in the area of the rotor ( 5 ), with the cross-sectional area expanding to a greater value (A 2 ) out to the end face ( 9 ) thereof.

1 . A camshaft arrangement for varying a relative angle position of at least one first cam of a camshaft relative to a second cam of the camshaft, comprising an angle adjustment device which has a stator and a rotor which is arranged so as to be rotatable relative to said stator, the rotor is connected in a rotationally fixed manner to a shaft, the stator is connected in a rotationally fixed manner to a hollow shaft, the shaft and the hollow shaft are arranged concentrically with respect to one another, the at least one first cam is connected in a rotationally fixed manner to the shaft, the at least one second cam is connected in a rotationally fixed manner to the hollow shaft, and the rotationally fixed connection between the rotor and the shaft is produced by at least one screw, the shaft abuts with a end face against an abutment surface of the rotor and is pulled against the abutment surface by the at least one screw, the shaft has, along its axial extent which is situated in a region of the rotor, a cross-sectional area (A 1 ) which increases in size up to the end face to a larger value (A 2 ) creating an enlargement. 
     
     
         2 . The camshaft arrangement as claimed in  claim 1 , wherein the enlargement of the cross-sectional area (A 2 ) is restricted to a region in a direct vicinity of the end face. 
     
     
         3 . The camshaft arrangement as claimed in  claim 2 , wherein the enlargement of the cross-sectional area (A 2 ) is restricted to the region (x) which extends at most 10 mm from the end face of the shaft. 
     
     
         4 . The camshaft arrangement as claimed in  claim 3 , wherein the enlargement of the cross-sectional area (A 2 ) is restricted to the region (x) which extends between 3 mm and 8 mm from the end face of the shaft. 
     
     
         5 . The camshaft arrangement as claimed in  claim 1 , wherein the shaft has a constant cross section along its axial extent which is situated in a region of the rotor that is outside the enlargement of the cross-sectional area. 
     
     
         6 . The camshaft arrangement as claimed in  claim 1 , wherein the external diameter (D A ) of the shaft at the end face corresponds to at least 80% of the external diameter (D AS ) of a screw head of the screw. 
     
     
         7 . The camshaft arrangement as claimed in  claim 6 , wherein the external diameter (D A ) of the shaft at the end face corresponds to at least 90% of the external diameter (D AS ) of the screw head of the screw. 
     
     
         8 . The camshaft arrangement as claimed in  claim 1 , wherein a transition of the external diameter of the shaft from a region of the smaller cross-sectional area (A 1 ) to a region of the enlarged cross-sectional area (A 2 ) is continuous. 
     
     
         9 . The camshaft arrangement as claimed in  claim 8 , wherein the transition of the external diameter of the shaft is rounded. 
     
     
         10 . The camshaft arrangement as claimed in  claim 1 , wherein the at least one screw consists of a single screw which is arranged as a central screw with an axis thereof concentric with respect to the shaft. 
     
     
         11 . The camshaft arrangement as claimed in  claim 10 , wherein the screw is an expansion screw. 
     
     
         12 . The camshaft arrangement as claimed in  claim 1 , wherein the shaft is formed, along an axial extent thereof which is situated in a region of the rotor, as a hollow shaft and has a constant internal diameter (D I ) up to the end face. 
     
     
         13 . The camshaft arrangement as claimed in  claim 1 , wherein the shaft has, along an axial extent thereof which is situated in a region of the rotor and up to the enlargement of the cross-sectional area, an external diameter (D A0 ) which amounts to at most 90% of an external diameter (D A ) of the shaft at the end face. 
     
     
         14 . The camshaft arrangement as claimed in  claim 13 , wherein, up to the enlargement of the cross-sectional area of the shaft, the external diameter (D A0 ) of said shaft amounts to between 80% and 90% of the external diameter (D A ) of the shaft at the end face. 
     
     
         15 . The camshaft arrangement as claimed in  claim 1 , wherein the angle adjustment device comprises a hydraulic adjustment device.