Patent ID: 8240285
Filing Date: 2012-08-14
Classification: F01L

Abstract:
1. A switchable bucket tappet for a valve drive of an internal combustion engine, comprising: a bucket basic body having a ring-like base being guided by a skirt projecting from an outer edge of the ring-like base in a bore of the internal combustion engine and a hollow cylindrical extension projecting from an inner edge of the ring-like base, the ring-like base having a region which is substantially symmetrical and an entirely thin-walled design and the ring-like base being acted on by at least one lifting cam; an inner body, which has a radial bore and an underside with an abutment formed in the underside for at least indirect contact with a gas exchange valve, running in the bore of the hollow cylindrical extension and being axially movable relative to the bucket basic body; two opposite coupling pistons running in a radial bore of the inner body, the coupling pistons, in order to obtain a full valve lift, being placed in engagement in sections with a driver surface of the bucket basic body; and a lost motion spring acting between the bucket basic body and inner body, wherein a zero valve lift is obtained when the coupling pistons are moved completely into the radial bore of the inner body, the inner body being formed, without a base, so as to be entirely free from contact with the cam or base circle, wherein the hollow cylindrical extension has a window-like through hole extending through a sidewall of the hollow cylindrical extension or, at a lower edge of the hollow cylindrical extension, a half-window-like recess, wherein the through hole or the window-like recess has an underside functioning as the driver surface for an upper side of the coupling pistons in a coupled state, and the through hole or the window-like recess is situated at an axial distance from the base of the bucket basic body, and wherein an anti-twist device is formed between the inner body and the bucket basic body.