Switchable cast iron rocker arm for a valve train of a heavy-duty internal combustion engine

Abstract

Proposed is a switchable rocker arm (1) made of cast iron for a valve train of a heavy-duty internal combustion engine, which rocker arm (1) has on its underside (2) at a first longitudinal end (3) a lift cam contact point (4), on its underside (2) at a second longitudinal end (5) a contact foot (6) for actuating at least one gas exchange valve and in the region of its longitudinal center (7) a bearing eye (8) for support against a cylinder head of the internal combustion engine, wherein in the underside (2) of the rocker arm (1) a bore (9) is provided at the first longitudinal end (3) in which an axially movable pressure piston (10) is seated, at the free end (12) of which the lift cam contact point (4) is arranged, in which pressure piston (10) a transverse receptacle (13) with two coupling slides (14) runs,which, for the purpose of engaging the cam lift, can be displaced section by section via a servo means into a respective coupling pocket (15) in the bore (9) of the rocker arm (1), and, for the purpose of disengaging the cam lift, can be displaced completely into the transverse receptacle (13) via another servo means, wherein a separate bushing (16) made of hardened steel is fixedly seated in the bore (9) of the rocker arm (1), which has the coupling pocket (15) in its inner ring wall (17) and in which inner ring wall (17) the pressure piston (10) is directly and axially movably received.