An exhaust gas-conducting section of an exhaust turbocharger comprises a duct with a through-flow opening which can be fully or at least partially blocked or released by a closure element of a control device. The closure element is designed as a poppet valve. The closure element can be moved by an actuator can be disposed in a wall of the exhaust gas-conducting section. The closure element has a closure body with an annular section surface on its bottom surface which faces the through-flow opening. The section surface corresponds to an element seat formed in the wall. Its top surface faces away from the bottom surface and is designed in a profiled manner in order to produce a top surface at least partially corresponding to another element seat and/or to achieve flow-optimized circulation.

An exhaust gas-conducting section of an exhaust turbocharger comprises a duct with a through-flow opening which can be fully or at least partially blocked or released by a closure element of a control device. The closure element is designed as a poppet valve. The closure element can be moved by an actuator can be disposed in a wall of the exhaust gas-conducting section. The closure element has a closure body with an annular section surface on its bottom surface which faces the through-flow opening. The section surface corresponds to an element seat formed in the wall. Its top surface faces away from the bottom surface and is designed in a profiled manner in order to produce a top surface at least partially corresponding to another element seat and/or to achieve flow-optimized circulation.

A method for operating an internal combustion engine, which comprises a combustion engine, a fresh gas line into which a fresh gas compressor is integrated, wherein the fresh gas compressor can be driven by an electric motor, and an exhaust gas line, in which an exhaust turbine, which has a variable turbine geometry, a bypass line with a bypass valve for bypassing the exhaust turbine as required, and, downstream of the exhaust turbine and the bypass line, an exhaust gas aftertreatment component are integrated, wherein if, during operation of the combustion engine, an operating temperature of the exhaust gas aftertreatment component is below a set temperature, the bypass line is at least temporarily released, the fresh gas compressor is driven by the electric motor, and the VTG is set to a closed position of at least 50% or at least 80% or at least 90% or 100%.

A method for operating an internal combustion engine, which comprises a combustion engine, a fresh gas line into which a fresh gas compressor is integrated, wherein the fresh gas compressor can be driven by an electric motor, and an exhaust gas line, in which an exhaust turbine, which has a variable turbine geometry, a bypass line with a bypass valve for bypassing the exhaust turbine as required, and, downstream of the exhaust turbine and the bypass line, an exhaust gas aftertreatment component are integrated, wherein if, during operation of the combustion engine, an operating temperature of the exhaust gas aftertreatment component is below a set temperature, the bypass line is at least temporarily released, the fresh gas compressor is driven by the electric motor, and the VTG is set to a closed position of at least 50% or at least 80% or at least 90% or 100%.

An engine system includes an engine with an intake manifold and an exhaust manifold, a turbocharger including a turbine in communication with the exhaust manifold and a compressor in communication with the intake manifold, and a regulator configured to control a flow of exhaust gas through the turbine. A controller of the engine system is operably connected with the regulator and is configured to monitor an engine load and an exhaust gas temperature during operation of the engine, identify a proscribed engine NOx emissions level based on the engine load and the exhaust gas temperature and, when the proscribed engine NOx emissions level is identified, modify the flow of exhaust gas through the turbine to reduce the energy extracted from the exhaust gas by the turbine and reduce a drive power provided to the compressor, thereby reducing a flow of intake air provided to the intake manifold by the compressor.

A variable geometry turbocharger (100) includes a bearing housing (10) including a bearing-housing side support portion (40) configured to support a radially outer portion (38) of a nozzle mount (16) from a side opposite to a scroll flow passage (4) in an axial direction of a turbine rotor (2), and wherein at least one of the following condition (a) or (b) is satisfied: (a) the bearing-housing side support portion (40) includes at least one bearing-housing side recess portion (46) formed so as to be recessed in the axial direction so as not to be in contact with the radially outer portion (38); (b) the radially outer portion (38) of the nozzle mount (16) includes at least one nozzle-mount side recess portion (62) formed so as to be recessed in the axial direction so as not to be in contact with the bearing-housing side support portion (40).

A variable-nozzle turbocharger includes a variable-vane mechanism that has an annular nozzle ring supporting an array of rotatable vanes connected to vane arms whose distal ends engage recesses in the radially inner periphery of a rotatable unison ring. Rotation of the unison ring causes the vane arms to pivot about their respective pivot axes at the proximal ends of the arms. The vanes are locked in their fully open position by a locking arrangement that includes locking tongues that extend radially inwardly from the inner periphery of the unison ring and contact the vane arms intermediate their distal and proximal ends.

A variable-nozzle turbocharger includes a variable-vane mechanism that has an annular nozzle ring supporting an array of rotatable vanes connected to vane arms whose distal ends engage recesses in the radially inner periphery of a rotatable unison ring. Rotation of the unison ring causes the vane arms to pivot about their respective pivot axes at the proximal ends of the arms. The vanes are locked in their fully open position by a locking arrangement that includes locking tongues that extend radially inwardly from the inner periphery of the unison ring and contact the vane arms intermediate their distal and proximal ends.

A turbocharger includes a three-way rotary turbine bypass valve (TBV) operable to selectively supply exhaust gases to a turbine feed passage leading to a turbine wheel, and/or to a bypass passage that bypasses the turbine wheel. The TBV is structured and arranged to close the bypass outlet of the valve when the turbine outlet is fully open, to partially open the bypass passage while the turbine outlet remains fully open, to fully open the bypass passage when the turbine outlet is partially closed, and to fully open the bypass passage when the turbine passage is fully closed. The TBV turns the exhaust gas flows through acute angles between inlet and outlets, mitigating pressure losses through the valve. Leakage to bypass is minimized by a labyrinth seal formed when the valve member closes the bypass outlet.

A turbocharger includes a three-way rotary turbine bypass valve (TBV) operable to selectively supply exhaust gases to a turbine feed passage leading to a turbine wheel, and/or to a bypass passage that bypasses the turbine wheel. The TBV is structured and arranged to close the bypass outlet of the valve when the turbine outlet is fully open, to partially open the bypass passage while the turbine outlet remains fully open, to fully open the bypass passage when the turbine outlet is partially closed, and to fully open the bypass passage when the turbine passage is fully closed. The TBV turns the exhaust gas flows through acute angles between inlet and outlets, mitigating pressure losses through the valve. Leakage to bypass is minimized by a labyrinth seal formed when the valve member closes the bypass outlet.