Abstract: A switchable component (1) of a valve train of an internal combustion engine is provided, with a housing (2) in whose borehole (3) an inner element (4) is held so that it can move telescopically. At least one coupling piston (7) guided by an anti-rotation locking device (6) is located in a radial borehole (5) of the inner element (4) in a decoupled case, with a section (10) that is flattened in some areas being provided on the coupling piston on one axial side (9) starting from its outer end (8). The borehole (3) of the housing (2) has a window (11) with a complementary engagement surface (12) against which, in a coupled case, the coupling piston (7) can be displaced with its flattened section (10) when passing through the cam base circle. An edge (13) between the outer end (8) and the flattened section (10) of the coupling piston (7) is provided with a bevel (14) that is a surface section of an ellipsoid whose longitudinal axis runs parallel to the flattened section (10).

Abstract: The invention proposes a switchable tappet (1) of a valve train of an internal combustion engine, said tappet comprising a hollow cylindrical housing (3) comprising a bottom (2), an inner element (5) being guided for relative axial displacement in a bore (4) of the housing (3), an at least indirect support for a gas exchange valve extending on a cam-distal front end (6) of the inner element (5), two diametrically opposing pistons as coupling elements (8) being arranged in a radial bore (7) of the inner element (5), which coupling elements (8), for effecting coupling [full valve lift], can be displaced partly beyond a parting surface (9) between the housing (3) and the inner element (5) into an entraining surface (12) of the housing (3) by the force of a compression spring (10a) clamped between inner front ends (10) of the coupling elements (8), wherein the entraining surface (12) is an direct constituent of a separate annular member (13) that is fixed in a cam-distal region of the bore (4) of the housing (3),

Abstract: A switchable component (1) of a valve train of an internal combustion engine is provided, with a housing (2) in whose borehole (3) an inner element (4) is held so that it can move telescopically. At least one coupling piston (7) guided by an anti-rotation locking device (6) is located in a radial borehole (5) of the inner element (4) in a decoupled case, with a section (10) that is flattened in some areas being provided on the coupling piston on one axial side (9) starting from its outer end (8). The borehole (3) of the housing (2) has a window (11) with a complementary engagement surface (12) against which, in a coupled case, the coupling piston (7) can be displaced with its flattened section (10) when passing through the cam base circle. An edge (13) between the outer end (8) and the flattened section (10) of the coupling piston (7) is provided with a bevel (14) that is a surface section of an ellipsoid whose longitudinal axis runs parallel to the flattened section (10).