Patent ID: 6997154

Claim:
A switch element for a valve drive of an internal combustion engine, the switch element comprising: an outer part having a bore therein and an annular groove facing the bore; an anti-rotation safety element fixed to the outer part; an inner element axially movable in the bore and orientated with respect to the outer part by way of the anti-rotation safety element, the inner element having a radial bore and being adapted to receive a hydraulic clearance equalization element having a pressure system; a lost-motion spring disposed in the bore of the outer part to urge the inner element away from the outer part; and two diametrically opposed pistons disposed in the radial bore, to be displaced at least partially into the annular groove to couple the inner element to the outer part, the pistons each having a substantially planar transverse lower surface to contact an inner surface of the outer part facing upwardly towards the annular groove, wherein the outer part has two diametrically opposed oil ports offset in a circumferential direction from the pistons, and the outer part also has at least one anti-rotation component providing anti-rotation guidance of the switch element relative to a surrounding structure.