A process for monitoring turbocharger operation in a machine is disclosed. The machine includes a power source having an intake manifold for supplying the power source with air and a plurality of turbochargers. Each turbocharger includes an air inlet passageway to receive air, a plurality of pressure sensors arranged within the inlet passageway, a compressor configured to pressurize air, an air outlet passageway to direct pressurized air from the compressor to the intake manifold, and an exhaust turbine operably driven by exhaust gas from the power source and coupled to the compressor by a turbine shaft. The process includes monitoring the differential pressure across the air inlet passageway for each turbocharger, comparing the differential pressures for each turbocharger and indicating an anomaly in turbocharger speed when the differential pressure for one turbocharger exceeds the differential pressure for another turbocharger by a threshold amount.

A shovel includes a boom cylinder that drives a boom and an arm cylinder that drives an arm. A hydraulic pump supplies operating oil to the boom cylinder and the arm cylinder. An engine is connected to the hydraulic pump and equipped with a supercharger. The engine is controlled to maintain a revolution speed within a certain definite range. A controller controls a rotating speed of the supercharger. The controller performs a process of increasing the rotating speed of the supercharger so as to increase a supercharging pressure generated by the supercharger before a hydraulic load is applied to the engine.

An engine braking system includes engine braking actuators for adjusting exhaust valve timings to engine braking timings in a cylinder-number braking mode. The system further includes an engine braking controller coupled to a control switch that produces a request indicating a requested cylinder-number braking mode. The engine braking controller is structured to transition exhaust valves to the engine braking timings, determine a control term to adjust intake air pressure for varying a braking power of the engine, and to adjust geometry of an exhaust turbine based on the control term. An adjusted speed of a compressor rotated by the exhaust turbine provides a change to intake air pressure that adjusts the braking power of the engine. Different levels of braking power are provided within different cylinder-number braking modes.

A number of variations may include a turbocharger bearing housing comprising a bearing bore, a rolling element bearing assembly including an inner race and an outer race having a plurality of ball bearings disposed therebetween, wherein the rolling element bearing assembly is disposed within the bearing bore, a shaft for rotating the rolling element bearing assembly, located and supported within the inner race, a tubular bearing spacer, having at least one radial opening, positioned within the bearing bore, a mounting bore, a generally tubular insert mounted in the mounting bore and extending into the at least one radial opening of the tubular bearing spacer, and a rotational speed sensor mounted to the tubular insert via threaded fitting or friction fit.

An exhaust-gas turbocharger having an electric drive unit for driving a compressor, a turbine, or a turbocharger shaft of the exhaust-gas turbocharger. The electric drive unit has a rotor and a stator. The rotor is equipped with a rotor body embodied around a rotation axis of the rotor. A receptacle for at least one permanent magnet is embodied on the rotor body. A permanent magnet is disposed in the receptacle of the rotor body. The rotor body is mountable using a threaded bushing on a turbocharger shaft of the exhaust-gas turbocharger. The rotor body has a further receptacle which extends in the direction of the rotation axis and in which the threaded bushing is disposed inside the rotor body. The further receptacle is disposed in the rotor body with an offset in the direction of the rotation axis relative to the receptacle.

The invention has an object to control an EGR amount accurately in transient time. An ECU switches EGR control to the one-valve EGR control and the both-valve EGR control based on a request EGR amount. When the EGR control is switched to the one-valve EGR control from the both-valve EGR control, an EGR valve of one bank is closed first. Next, during a time period until an opening degree restriction time period elapses after the EGR valve is closed, an opening degree of an EGR valve of the other bank is restricted to be smaller than a one-valve target opening degree. Subsequently, when the opening degree restriction time period elapses, restriction of the opening degree of the EGR valve is cancelled, and the opening degree of the EGR valve is changes to the one-valve target opening degree.

The present invention relates firstly to a method for operating a compressor powered by an internal combustion engine for compressing air. Furthermore, the invention relates to a compressor, which is suitable for executing the method according to the invention. A first turbocharger for supplying pre-compressed air to the internal combustion engine is disposed in an exhaust flow of the internal combustion engine. Furthermore, a second turbocharger for pre-compression of the air to be compressed by the compressor is disposed in the exhaust flow of the internal combustion engine. The method according to the invention first comprises a step in which a monitoring of a pressure of the pre-compressed air generated by the first turbocharger occurs during an operating state of the compressor. In a further step of the method, a termination of the operating state occurs as soon as the monitored pressure falls below a previously determined value.

The speed of a turbocharger may be estimated using data from sensors that are readily available in most engine management systems. In some cases, a pressure measurement from a MAP sensor may be used, in combination with one or more computational models, to provide an efficient, lower cost estimate of turbo speed that can be used to control operation of the engine and/or the turbocharger.

An internal combustion engine includes a cylinder block that defines a cylinder and a cylinder head positioned relative to the cylinder block. A reciprocating piston is arranged inside the cylinder for compressing an air and fuel mixture at a geometric compression ratio of at least 10:1. A crankshaft is arranged in the cylinder block and rotated by the piston. An intake valve is operatively connected to the cylinder head and controls delivery of air to the cylinder for combustion therein. A mechanism provides late intake valve closing via constant peak lift of the intake valve over at least 5 degrees of crankshaft rotation. A multi-stage boosting system, having a turbocharger, a supercharger, and a continuously variable transmission for varying the supercharger's rotating speed, is regulated by a controller to selectively pressurize air being received from the ambient for delivery to the cylinder.

Proposed is a gas heat-pump system capable of supplying recirculation exhaust gas using a motor-driven turbocharger and thus actively controlling an amount of flowing recirculation exhaust gas and pressure thereof.