Systems and methods for operating exhaust valves of an internal combustion engine with poppet exhaust valves are described. The systems and methods provide for locking exhaust valves in a closed state when the exhaust valves are in mechanical communication with a base circle of a camshaft lobe. Locking the exhaust valves in a closed state may reduce the possibility of exhaust pressures opening the exhaust valves at times they may not be desired to be open.

The variable valve actuating device (20) comprises a switch pin (53) slidably received in the valve lifter (24) so as to selectively abut the end surface of the valve stem as the valve lifter is actuated by the cam. The device further comprises a first spring retainer (36) attached to an intermediate part of the valve stem (32) to engage a first valve spring (35), and a second spring retainer (44) slidably engaged by an end part of the valve stem to engage a second valve spring (43). The valve stem is provided with a stem end (39) which is enlarged with respect to a part of the valve stem slidably engaging the second spring retainer so as to define a shoulder surface (40a) that engages the second spring retainer against a spring force of the second valve spring.

A valve spring retainer for an internal combustion engine includes a body having a lower portion and an upper portion. The lower portion defines a radial flange and a first opening extending axially therethrough. The upper portion includes a first wall and a re-entrant lip. The first wall extends at least partially axially away from an outer perimeter edge of the radial flange. Together, the first wall and the radial flange define an open reservoir for receiving and retaining oil therein. The re-entrant lip extends from an outer end of the first wall at least partially radially inward toward a central axis of the first opening. The re-entrant lip extends over a portion of the reservoir defined by the first wall and the radial flange.

A compression release type engine brake includes a first opening unit and a second opening unit each including an exhaust rocker arm, an adjusting screw provided at an end portion of the exhaust rocker arm, a brake module in which brake oil is selectively and a brake piston mount portion is formed therein, a brake piston which is selectively protruded according to the oil supply inside the brake module, a reset member selectively exhausting the oil in the brake module, and a valve bridge connected to the brake piston and provided with an exhaust valve, and wherein a rocker arm protrusion is formed in the exhaust rocker arm of at least one of the first opening unit and the second opening unit, and the shaft spring presses the rocker arm protrusion and adjusts a distance between the first opening unit and the second opening unit.

A pivot bearing (1) for a hydraulic clearance compensation element (2), especially of a valve train of an internal combustion engine, is provided in which the pivot bearing (1) has a first part (3) projecting in an axial direction (a) with a surface (4) that is convex at least in some sections and also a second part (5) with a surface (6) that is concave at least in some sections for at least partially holding the first part (3). To optimize the production of such a pivot bearing and to minimize the associated costs, the invention provides that the first part (3) is constructed at least partially as a ball, wherein the second part (5) surrounds the ball (3) with undercut in the axial direction (a).

A pivot bearing (1) for a hydraulic clearance compensation element (2), especially of a valve train of an internal combustion engine, is provided in which the pivot bearing (1) has a first part (3) projecting in an axial direction (a) with a surface (4) that is convex at least in some sections and also a second part (5) with a surface (6) that is concave at least in some sections for at least partially holding the first part (3). To optimize the production of such a pivot bearing and to minimize the associated costs, the invention provides that the first part (3) is constructed at least partially as a ball, wherein the second part (5) surrounds the ball (3) with undercut in the axial direction (a).

The invention relates to a shaft, particularly a cam shaft (1), comprising a hollow shaft section (10) with at least one radial inlet opening (11a, 11b) for evacuating a gas through said hollow shaft section (10), and comprising a splash-guard device (4) arranged in the region of the radial inlet opening (11a, 11b) on the hollow shaft section (10). According to the invention, the splash-guard device (4) has a radially exposed cover with radial passage openings (8) and protrusions between said passage openings (8). The protrusions can, in particular, be in the form of ribs (9).

The invention relates to a shaft, particularly a cam shaft (1), comprising a hollow shaft section (10) with at least one radial inlet opening (11a, 11b) for evacuating a gas through said hollow shaft section (10), and comprising a splash-guard device (4) arranged in the region of the radial inlet opening (11a, 11b) on the hollow shaft section (10). According to the invention, the splash-guard device (4) has a radially exposed cover with radial passage openings (8) and protrusions between said passage openings (8). The protrusions can, in particular, be in the form of ribs (9).

A variable valve driving mechanism of an engine includes a rocker arm configured to control open and close of a valve and a servo rocker arm arranged in parallel to the rocker arm. A swing end of the servo rocker arm extends to the top of the swing end of the rocker arm. A valve adjustment gap provided in the swing direction of the servo rocker arm and the rocker arm is formed between the servo rocker arm and the rocker arm. A gap compensating device telescopically filling the valve adjustment gap and configured to adjust the valve to be delayed to close or open in advance when extending to the valve adjustment gap is provided between the servo rocker arm and the rocker arm.

A variable valve driving mechanism of an engine includes a rocker arm configured to control open and close of a valve and a servo rocker arm arranged in parallel to the rocker arm. A swing end of the servo rocker arm extends to the top of the swing end of the rocker arm. A valve adjustment gap provided in the swing direction of the servo rocker arm and the rocker arm is formed between the servo rocker arm and the rocker arm. A gap compensating device telescopically filling the valve adjustment gap and configured to adjust the valve to be delayed to close or open in advance when extending to the valve adjustment gap is provided between the servo rocker arm and the rocker arm.