Abstract: In a turbocharger system for internal combustion engines, the internal combustion engine has at least one combustion chamber with a variable volume and a swept volume determined by the sum of the differential volumes between the smallest and largest volumes of the combustion chambers of the internal combustion engine. The turbocharger system associated to the internal combustion engine has at least one turbine arranged in the exhaust gas pipe of the internal combustion engine and provided with a flow channel which opens via an annular jet-shaped region onto a turbine wheel. A guiding apparatus arranged in the opening region of the flow channel has a variable guiding grid with adjustable guiding blades which make it possible to obtain free flow sections of different sizes and which acts as a throttle during braking in an adjustable manner, depending on the operational parameters of the internal combustion engine, for determining the narrowest flow section in the exhaust gas pipe that leads to the turbine.

Abstract: In the case of a method for operationally testing an exhaust gas turbocharger with a variable turbine geometry, actual values are detected of operating quantities which influence the operational capability of the exhaust gas turbocharger and which comprise main quantities which are used for deciding whether a fault exists in the exhaust gas turbocharger, as well as auxiliary quantities which describe a component of the exhaust gas turbocharger and are used for identifying faults in this component. In a first step, for fault detection, a quantity is measured as the main quantity which determines the engine air supply. In a second step, at least one auxiliary quantity is measured for the fault identification and, in the event of an unacceptable deviation of the actual auxiliary quantity value from the desired auxiliary quantity value, a fault signal is generated.

Abstract: An exhaust gas turbocharger for an internal-combustion engine has a turbine wheel which is arranged in a housing of the exhaust gas turbocharger and to which exhaust gas can be fed by way of a flow duct constructed in the housing. A variable baffle is provided for adjusting the flow cross-section of the flow duct. In order to equip the exhaust gas turbocharger with a braking function at low manufacturing and mounting expenditures, the baffle is movably accommodated in a matrix which is detachably held on the housing. The baffle and the matrix form an exchangeable braking module.

Abstract: In an engine braking arrangement for an internal combustion engine with an exhaust gas turbocharger including a turbine arranged in the engine exhaust duct and a compressor driven by the turbine and arranged in the engine intake duct, a brake valve disposed in the exhaust duct upstream of the turbine and a pressure relief line extending from the exhaust duct upstream of the turbine rotor to an area downstream of the turbine and including a stop valve, the stop valve is a rotationally adjustable rotary valve operable by an actuating device depending on the intake pressure in the intake duct.

Abstract: In an engine braking operation for a supercharged internal-combustion engine which has an exhaust gas turbocharger having a turbine with a variable turbine geometry, the turbine geometry is adjusted between a ram position to reduce the effective turbine cross-section and an opening position to open the effective turbine cross-section. In order to influence the action of the engine brake simply, such that a braking is adapted to different situations, the variable turbine geometry is adjusted between a definable hard braking adjustment and a definable soft braking adjustment. The hard braking adjustment is situated between the ram position and a drive starting position assigned to the fired drive operating mode. The soft braking adjustment is situated between the drive starting position and the opening position. The hard braking adjustment is selected so that the engine braking power is higher than in the soft braking adjustment.

Abstract: An exhaust gas turbocharger for an internal-combustion engine, whose exhaust gas turbine has a rotor disk with at least one semiaxial and one radial flow inlet cross-section, and is provided with a variable turbine geometry for the variable adjustment of at least one flow inlet cross-section. Furthermore, a compressor is provided in the intake system of the internal-combustion engine. In order to improve the efficiency of the exhaust gas turbocharger in a wide operating range, the ratio of the compressor outlet diameter to the average turbine inlet diameter can be variably adjusted according to the adjustment of the variable turbine geometry between a minimal value and a maximal value, the minimal value being lower than 1.1.

Abstract: In an exhaust gas re-circulation arrangement for a supercharged internal combustion engine including an exhaust gas turbocharger with an exhaust gas turbine and a compressor, first and second exhaust pipes extending from the engine separately to the exhaust gas turbine, a charge air duct extending from the compressor to the engine and an exhaust gas recirculation line extending from one of the exhaust pipes upstream of the exhaust gas turbine to the charge air duct downstream of the compressor, the exhaust gas turbine has two turbine inlet flow passages, which provide for different flow volumes and to each of which one of the exhaust pipes is connected and a control arrangement is provided for controlling the exhaust gas flow through the turbine inlet flow passages so as to control the pressure in the exhaust gas re-circulation line to be higher than in the charge air intake duct.

Abstract: An exhaust turbocharger for an internal combustion engine has a main compressor for compressing the fresh air supplied to the engine, an additional compressor for compressing combustion gases to be recycled to the engine, and a turbine that can be driven by the exhaust gases from the engine and which serves to drive the main compressor and the additional compressor. The turbine has an adjustable geometry which facilitates optimization of engine operation regarding pollutant emissions, fuel consumption, and performance.

Abstract: A method automatically controls the engine brake of a motor vehicle in which, in the coasting operation during a transmission shifting operation, the resulting braking torque acting upon the internal-combustion engine is reduced. In order to be able to control as precisely and inexpensively as possible the torques acting upon the internal-combustion engine in the engine braking operation of the vehicle during a transmission shifting operation, the injected fuel quantity is increased during the shifting operation.

Abstract: A method and apparatus for regulating a supercharged internal combustion engine that has two rows of cylinders, with an exhaust turbocharger associated with each row, a control signal for adjusting at least one exhaust turbocharger is generated in a regulating unit, taking into account state parameters that describe the operating state of the engine. In order to supply the supercharged internal combustion engine uniformly with combustion air to regulate the engine, a state parameter is measured in the vicinity of the compressor of the exhaust turbocharger and a regulating parameter is formed from the state parameter according to a given control law. The control parameter is supplied as a control signal to a control member that influences the effective turbine cross section.

Abstract: An exhaust gas turbocharging system for an internal combustion engine including a turbine portion with adjustable turbine geometry for powering a compressor portion which delivers a pressurized charge air mass flow to the internal combustion engine air intake. A charge regulator controls the turbine geometry so that the cross-section of exhaust gas flow to the turbine portion is decreased with an increased working load of the internal combustion engine. It is further proposed that at least one heat exchanger is exposed to the charge air circuit so that heated air is fed thereto for heating such as to heat engine lubricating oil.

Abstract: In a piston for an internal combustion engine, which includes in its top an annular cooling oil passage which, at one side of the piston, is in communication with a cooling oil supply passage extending axially through the piston and has a bottom opening through which cooling oil is supplied by an injection nozzle, and, opposite the cooling oil supply passage, a cooling oil return passage in communication with the annular cooling oil passage for removing the cooling oil therefrom, at least the cooling oil supply passage includes cooling oil retaining pockets which retain, during outward movement of the piston, part of the cooling oil supplied to the cooling oil supply passage and from which the retained cooling oil is dislodged and moved to the annular cooling oil passage during inward movement of the piston.

Abstract: In a motor brake arrangement for an internal combustion engine including an exhaust gas turbocharger having a turbine, a compressor and an exhaust duct leading from the engine to the turbine, a shutoff valve is arranged in the exhaust duct upstream of the turbine and a bypass line is connected to the exhaust duct upstream of the shutoff valve and extends to the turbine to supply gas under pressure from the exhaust duct to the turbine adjacent the turbine wheel.

Abstract: A method adjusts the engine braking performance of a supercharged internal-combustion engine. The exhaust gas turbocharger of the internal-combustion engine is provided with a variably adjustable turbine geometry for changing the effective turbine cross-section. In order to be able to transmit high brake powers, while the directional control is simultaneously high, a wheel slip control is implemented in the engine braking operation. The rotational speed of at least one wheel is measured and is compared with a reference value. In the event of a deviation of the measured rotational wheel speed from the reference value, a control signal is generated and fed to a control element which acts upon the variable turbine geometry for reducing the wheel slip.

Abstract: A radial-flow exhaust-gas turbocharger turbine is provided with a row of adjustable guide blades which are rotatable via adjusting shafts mounted in a casing. The guide blades are each provided with sealing discs on their longitudinal sides running at right angles to the adjusting-shaft axes. The diameter of the sealing discs is a multiple of the thickness of the guide blades. The sealing discs which are located on the side remote from the adjusting shafts form bearing points for the guide blades in the casing.

Abstract: In a method and apparatus for controlling a supercharged internal combustion engine including an exhaust gas turbocharger having variable turbine inlet vanes, an engine control unit includes an engine performance graph with control parameters for a multitude of engine operating points compressor performance graph is also recorded in the engine performance which represents for various exhaust gas turbocharger speeds a particular relationship between mass flow through the compressor and total pressure ratio. A multitude of engine operating curves for constant turbine guide vane positions and constant engine speeds for various engine loads and engine operating modes are also recorded and retrieved by the engine control unit for controlling the engine depending on desired engine load and engine speed for adjusting the turbine inlet vanes.

Abstract: In an internal combustion engine with a turbocharger with a turbine wheel arranged in its exhaust gas duct system and an exhaust gas release arrangement disposed in the exhaust gas duct system ahead of the turbine wheel of the turbocharger, the exhaust gas release arrangement comprises a valve with a valve seat formed in such a way that different controllable operating state-based flow cross-sections are provided for the controlled release of exhaust gases from the exhaust gas duct system ahead of the turbine wheel during motor brake and during power operation of the internal combustion engine.

Abstract: In the engine braking operation of supercharged internal combustion engines, the braking power is generated by backing-up the exhaust gas before it enters an exhaust gas turbine of an exhaust gas turbocharger from an actuator in the exhaust gas duct. In order to make it possible to control the braking power within the operating limits of the exhaust gas turbocharger, the actual value and a maximum value of the turbine inlet pressure within the operating limits of the exhaust gas turbo supercharger are inferred from a performance graph of the internal combustion engine, which performance graph includes an electronically stored compressor performance graph of the supercharged air compressor which represents the relationship between mass throughput and total pressure ratio of the compressor and in which a plurality of engine operating lines for certain actuator positions and certain engine speeds as well as for a constant turbine inlet pressure are recorded.

Abstract: In an exhaust gas turbocharger for an internal combustion engine with a turbine casing including a turbine inlet structure with two flow passages separated by a partition, a turbine control valve is arranged in the partition and is in communication with a turbine bypass flow passage, which is disposed in the partition and extends to the turbine outlet for discharging exhaust gases from at least one of the two turbine inlet flow passages to the turbine outlet under the control of the turbine bypass valve.

Abstract: In an exhaust gas turbocharger turbine for an internal combustion engine with a turbine housing having an annular flow path, a control sleeve axially movably supported in an annular space formed in the turbine housing adjacent the annular flow path and having at its front end a flow guide structure with vanes for guiding the exhaust gas flow when the flow guide structure is disposed in the annular flow path, a ring is disposed at the front end of the control sleeve in front of the flow guide structure such that the annular space is covered and sealed when the control sleeve is fully retracted into the annular space whereby flow losses are substantially reduced.