Switchable cam follower

Abstract

The invention proposes a switchable cam follower () for a valve train of an internal combustion engine, said cam follower comprising two elements () telescoped into each other and, axially displaceable relative to each other. A bore () comprising at least one piston () extends in the inner element (). The piston () has, on a portion of its outer peripheral surface (), a stepped entraining surface () that starts from the first front end () of the piston () facing the outer element (). For achieving coupling, the piston () can be displaced with this entraining surface () onto a flat counter surface () of the other element (). The entraining surface () of the piston () extends, starting from the first front end (), toward a second front end () of the piston () while tapering into a conical shape generally in the direction toward a longitudinal axis of the piston (). Besides this, an edge region () of the entraining surface () on the first front end () is additionally provided with a cylindrical, outwards arched (with reference to a starting point of the radius (R)) contour () that extends orthogonally to the longitudinal axis of the piston (). In this way, during the coupled state of the piston () and its inevitable tilting, the edge abrasion feared in the prior art does not occur any longer. The manufacturing tolerances in the region of coupling can be coarsened, i.e. slackened.