Patent ID: 7246589

Claim:
A valve train of an internal combustion engine comprising a tappet and a tappet pushrod that is actuated by said tappet, said tappet pushrod being at least partly hollow and comprising on one end, a first support for an at least indirectly contacting pressure piston of a hydraulic lash adjuster of said tappet that follows a periodic driving element, typically a cam, a second support for a follower member, typically a rocker arm, being arranged on a further end of the tappet pushrod, said first support comprising a passage for hydraulic medium that can be routed out of the pressure piston during operation of the internal combustion engine into an interior of the tappet pushrod, wherein a pipette means is installed in the tappet pushrod for retaining, during a standstill of the internal combustion engine, a hydraulic medium column which, as viewed in gravity direction, is situated under the pipette means, the second support comprises a passage for hydraulic medium to the follower member and the pipette means is configured at the same time as a choke for limiting a hydraulic medium flow to the passage of the second support, or a choke for limiting a hydraulic medium flow is associated to the pipette means, a bushing is installed in the tappet pushrod, which bushing is one of fixed in position in the interior of the tappet pushrod or is a part of the tappet pushrod and comprises two axially opposing annular collars between which a closing body, typically a ball, extends for slight displacement, a sealing valve seat for the closing body for forming the pipette means is generated on that one of the annular collars that faces the first support, and a stop for the closing body comprising at least one through-opening for forming a choke for the hydraulic medium extends on that one of the annular collars that faces the second support.