Patent ID: 8225759

Claim:
A valve drive for activation of gas exchange valves of internal combustion engines, comprising: at least one camshaft driven by a crankshaft of the internal combustion engine; axially displaceable cams disposed on the camshaft, said cams being connected, either directly or by way of intermediate elements, with the gas exchange valve, a shift gate disposed on a housing of the internal combustion engine, in an axially displaceable manner, said gate having a gate groove that widens counter to a direction of rotation of the camshaft, wherein said gate groove is adapted for contact with contact surfaces of displaceable cam contours of the cams, for valve stroke switching between two different cam profiles; two tappets that are mounted on a rotating adjustment shaft, and firmly connected with the shift gate; two adjustment devices mounted on the adjustment shaft so as to rotate with it, wherein said tappets are axially displaceable between said two adjustment devices, and face sides of the tappets that face the adjustment devices are each provided with a contour that is connected with a respective adjustment device by way of a guide pin; and a gear wheel disposed on the adjustment shaft so as to rotate with it and in an axially displaceable manner, said gear wheel adapted to be brought into and out of engagement with a gear segment that is firmly disposed on the camshaft.