Abstract: A device for actuating outlet valves that are acted on via a valve bridge of a valve-controlled internal combustion engine for motor vehicles includes a first piston-cylinder unit in the force flow between a cam of a driving camshaft and one of the outlet valves. When one of the outlet valves opens under the action of exhaust-gas counterpressure, play compensation in the valve drive can be produced in order to hold the one of the outlet valves open by the first piston-cylinder unit. A second, coaxial piston-cylinder unit interacts with a positionally fixed counter bracket and controls a discharge duct out of the pressure chambers of the two piston-cylinder units. The piston of the first piston-cylinder unit is preloaded in a readjustment direction by a spring. To reliably obtain a lack of play in the valve drive in particular during engine braking operation, the readjustment spring acts, without being supported in the valve bridge, on the pistons of both piston-cylinder units.

Abstract: A device for actuating outlet valves that are acted on via a valve bridge of a valve-controlled internal combustion engine for motor vehicles includes a first piston-cylinder unit in the force flow between a cam of a driving camshaft and one of the outlet valves. When one of the outlet valves opens under the action of exhaust-gas counterpressure, play compensation in the valve drive can be produced in order to hold the one of the outlet valves open by the first piston-cylinder unit. A second, coaxial piston-cylinder unit interacts with a positionally fixed counter bracket and controls a discharge duct out of the pressure chambers of the two piston-cylinder units. The piston of the first piston-cylinder unit is preloaded in a readjustment direction by a spring. To reliably obtain a lack of play in the valve drive in particular during engine braking operation, the readjustment spring acts, without being supported in the valve bridge, on the pistons of both piston-cylinder units.