Valve stem seal for a lift valve, especially in an internal combustion engine

摘要

A valve stem seal for a lift valve, especially in an internal combustion engine, is described with a sealing element, which, with a sealing lip, bears on the valve stem, and a tubular spring which lies in a ring groove with an approximately semi-circular cross-section, running around the outside of the sealing element approximately at the level of the sealing lip, and which presses the sealing lip on to the valve stem. In order to prevent the tubular spring from sliding out of the ring groove, especially when assembling the valve stem seal, a bead is provided as part of the sealing element, which when the tubular spring is inserted bears on the radially outer circumference thereof and closes approximately three-quarters of the cross-section of the ring groove.