Abstract: A hydraulic cam follower (1) for the simultaneous actuation of several equal-acting gas-exchange valves is provided, especially for a tappet pushrod valve train of an internal combustion engine, and includes an outer part (2), whose base (3) forms or is at least indirectly connected to a cam contacting surface (4) and from whose head (5) hollow-cylindrical guides (6) extend in the same number as the equal-acting gas-exchange valves in a direction towards the base (3). Each guide (6) is formed by a cutting process, such as internal round reaming or internal round broaching, and a housing (7) of a hydraulic play compensation element (8) is provided in each guide with its outer casing (9) fine-machined by grinding, which housing (7) sits with its bottom side (10) on an inner side (11) of the bottom (3) of the outer part (2).

Abstract: A variable valve drive for changing control timing of cam-actuated gas-exchange valves of an internal combustion engine is provided, with a tappet (6a, 6b, 6c), which, with convex cam engaging contour (5), engages a cam (4a, 4b, 4c) of a camshaft (3a, 3b, 3c) and which is guided so that it can move in the longitudinal direction in a rotatable tappet guide (7a, 7b, 7c), whose rotational angle (9) is adjustable for changing the control timing. In this way, the tappet guide (7a, 7b, 7c) can rotate about a rotational axis (8) parallel to a longitudinal axis (2) of the camshaft (3a, 3b, 3c).

Abstract: A device (1) for the hydraulic lash adjustment for several identically acting gas-exchange valves per cylinder of a valve train of an internal combustion engine is provided, the device (1)including a common housing (2) with directly adjacent pressure pistons (3) provided corresponding to the number of identically acting gas-exchange valves. Each pressure piston (3) moves relative to the housing in an axial direction in a separate guide (4) in the housing (2), and also has a support (6) for an at least indirect contact with the corresponding gas-exchange valve on a distal end (5) away from the housing, and a non-return valve (8) in the region of a housing bottom (7) wherein a separate high-pressure chamber (9) is associated with each pressure piston (3) in which the non-return valve (8) opens. The high-pressure chamber (9) extends axially between the bottom (7) of the pressure piston (3) and a base (10) of the housing (2), and the pressure pistons (3) arranged in the common housing (2) have a common reservoir.

Abstract: A device (1) for the hydraulic lash adjustment for several identically acting gas-exchange valves per cylinder of a valve train of an internal combustion engine is provided, the device (1) including a common housing (2) with directly adjacent pressure pistons (3) provided corresponding to the number of identically acting gas-exchange valves. Each pressure piston (3) moves relative to the housing in an axial direction in a separate guide (4) in the housing (2), and also has a support (6) for an at least indirect contact with the corresponding gas-exchange valve on a distal end (5) away from the housing, and a non-return valve (8) in the region of a housing bottom (7) wherein a separate high-pressure chamber (9) is associated with each pressure piston (3) in which the non-return valve (8) opens.

Abstract: A valve train for an internal combustion engine is provided, with the valve train having a switchable rocker arm assembly (1) with a plurality of rocker arms (6, 7, 8) for activating at least one gas exchange valve (2), and also having at least one camshaft (3) with differently contoured cams (4, 5) through which different adjusting displacements can be imparted to individual rocker arms of the rocker arm assembly (1). The assembly further includes a switching device (9) for selectively activating the rocker arms for driving the gas exchange valve (2) with a varying valve lift.

Abstract: A valve train for an internal combustion engine is provided, with the valve train having a switchable rocker arm assembly (1) with a plurality of rocker arms (6, 7, 8) for activating at least one gas exchange valve (2), and also having at least one camshaft (3) with differently contoured cams (4, 5) through which different adjusting displacements can be imparted to individual rocker arms of the rocker arm assembly (1). The assembly further includes a switching device (9) for selectively activating the rocker arms for driving the gas exchange valve (2) with a varying valve lift.

Abstract: A variable valve drive for changing control timing of cam-actuated gas-exchange valves of an internal combustion engine is provided, with a tappet (6a, 6b, 6c), which, with convex cam engaging contour (5), engages a cam (4a, 4b, 4c) of a camshaft (3a, 3b, 3c) and which is guided so that it can move in the longitudinal direction in a rotatable tappet guide (7a, 7b, 7c), whose rotational angle (9) is adjustable for changing the control timing. In this way, the tappet guide (7a, 7b, 7c) can rotate about a rotational axis (8) parallel to a longitudinal axis (2) of the camshaft (3a, 3b, 3c).