Patent ID: 8161929

Claim:
A switchable tappet of a valve train of an internal combustion engine, the tappet comprising: a hollow cylindrical housing comprising a bottom; an inner element constructed for relative axial displacement in a bore of the housing; at least one indirect support for a gas exchange valve extending on a cam-distal front end of the inner element; and at least one coupling element constructed to selectively couple the inner element with the housing, wherein in an uncoupled mode the at least one coupling element extends completely in a radial bore of the inner element and wherein in a coupled mode the coupling element is displaced in a radially outward direction partly beyond a parting surface between the housing and the inner element into an entraining surface of the housing by the force of at least one compression spring acting on an inner front end of the coupling element; wherein the entraining surface is a direct constituent of a separate annular member that is fixed in a cam-distal region of the bore of the housing, wherein a lost motion spring means extends in a cylindrical hollow space formed between an underside of the bottom of the housing and a cam-side flat front end of the inner element, and wherein the inner element is substantially disk-shaped and the parting surface between the housing and the inner element permits relative vertical movement of the inner element in the cam-distal direction in the uncoupled mode.