Tappet for the valve gear of an internal combustion engine

Abstract

A tappet (,) is designed to be coupled for different lifts of at least one gas exchange valve. It comprises an outer annular section (,) which concentrically encloses a circular section (,). Both sections (,) are axially movable relative to each other and are loaded in the region of their bottoms (,) by cams of different lifts. Slides (,) extend in receptions (,) of the bottoms (,). The first slide (,) cooperates with locking means (,) which scan a signal track on the opposing cam and, in a response to a lift of the signal track, block or permit a longitudinal movement of the first slide (,), the locking means yielding in their releasing direction under action of force. At the same time, the third slide (,) delimits on its radially outer end face (,), a pressure chamber for hydraulic medium. A displacement of all the slides (,) into their coupled position can be effected through this hydraulic medium. A particular advantage of the invention is that, on the one hand, the pressure chamber (,) for hydraulic medium is spatially separated from the locking means (,) so that no complicated sealing measures are required in the region of the locking means (,) because no hydraulic medium losses are to be expected. On the other hand, the locking means (,) are elastically mounted in cam-distal direction. They thus possess a certain yielding property for the event that due to the course of the signal track, the locking means (,) are prevented from taking their locking position on the first slide (,) by a section situated between locking recesses (,) of the first slide (,).