A spool is configured to reciprocate at an inside space of a sleeve and includes: a spool tube; a spool cover, which closes an end portion of the spool tube located on a camshaft side; a pressure accumulation space, which is formed at an inside of the spool tube; a supply passage, which is configured to connect between the pressure accumulation space and a supply port; a control passage, which is configured to connect between the pressure accumulation space and a primary control port; and a control passage, which is configured to connect between the pressure accumulation space and a secondary control port. A variable volume space is formed between the spool cover and a sleeve bottom. The sleeve includes a breathing hole at an outside of the inside space while the breathing hole is a hole that communicates between the variable volume space and the atmosphere.

An engine combustion chamber structure includes a combustion chamber of an engine and a fuel injection valve. The fuel injection valve injects fuel toward a cavity in a crown face of a piston. The cavity includes a first cavity that is provided in a radially central region of the crown face with a first bottom having a first depth, a second cavity provided in an outer side of the first cavity with a second bottom having a second depth being smaller than the first depth, a connecting portion, and a standing wall region disposed further in a radially outer side than the second bottom of the second cavity. The second bottom is provided lower than an upper end, of the connecting portion. A lower section of the standing wall region is provided further in a radially inner side than an upper edge of the standing wall region.

A camshaft adjuster for adjusting the phase angle between a crankshaft and a camshaft of an internal combustion engine comprises an actuator, in particular, an electric motor, and an adjustment module, which comprises a drive element, which can be driven by the crankshaft, and an output element, which can be rotated relative to the drive element to a limited extent and which is provided to be securely coupled to the camshaft, wherein a signal generator, which is arranged so as to be fixed in position on the internal combustion engine and which has an inductance, is inductively coupled to a measurement circuit, which is integrated into the adjustment module and which has at least one resonant circuit component having electrical properties that depend on the said phase angle.

An engine control system of a vehicle includes a cylinder control module configured to: determine a target sequence for at least activating and deactivating cylinders of an engine based on a torque request; and activate and deactivate the cylinders of the engine according to the target sequence. A values module is configured to determine, based on the target sequence, a plurality of coefficients and an offset value. An indicated mean effective pressure (IMEP) determination module is configured to determine an IMEP of a first cylinder based on: the plurality of coefficients; the offset value; and a plurality of engine speeds at a predetermined crankshaft positions, respectively.

Methods and systems are provided for controlling operating of a split exhaust engine system including a scavenge exhaust gas recirculation system based on a composition of constituents within a total flow through the scavenge exhaust gas recirculation system. In one example, a method may include adjusting an engine operating parameter in response to individual flows of each of burnt gases, fresh air, and fuel to an intake passage, upstream of a compressor, from a scavenge manifold coupled to scavenge exhaust valves, the individual flows of each of the burnt gases, fresh air, and fuel determined based on a valve opening overlap between the scavenge exhaust valves and intake valves of the engine.

A retard supply passage connects between a hydraulic oil supply source and a retard chamber through a hydraulic oil controller. An advance supply passage connects between the hydraulic oil supply source and an advance chamber through the hydraulic oil controller. A drain passage and a drain passage connect the retard chamber and the advance chamber to an oil discharge portion, respectively. A recycle passage connects the drain passage and the drain passage to the retard supply passage and the advance supply passage, respectively. A recycle check valve enables only a flow of hydraulic oil from the drain passages toward the retard supply passage and the advance supply passage in the recycle passage. The recycle passage is connected to the drain passages at an inside of the hydraulic oil controller.

A method for determining the mass m of air trapped in each cylinder of an internal combustion engine comprises determining, a value for each quantity of a first group of reference quantities comprising at least intake pressure P measured inside the intake manifold, engine rotation speed n, mass of gases produced by the combustion in the previous operating cycle (OFF) and present in the cylinder, determining, the actual inner volume V of each cylinder as a function of the engine rotation speed n, of the lift H of the intake valve and of the closing delay angle IVC of the intake valve, and determining the mass m of air trapped in each cylinder as a function of the first group of reference quantities and of the actual volume V inside each cylinder, on the basis of the aforesaid quantities P, V, OFF.

The present invention refers to a charge changing control device for a reciprocating engine, comprising at least one cam follower configured for being pivotably actuated around a pivot axis (P) upon rotational movement of a camshaft, and an adjustment unit configured for setting at least three different charge-changing modes of the device by translationally displacing the pivot axis relative (P) to a rotational axis (R) of the camshaft.

A control device for an engine is provided, which includes variable intake and exhaust valve operating mechanisms, a supercharger provided to an intake passage and configured to boost intake air introduced into a cylinder, and a controller. The controller drives the supercharger when the engine operates in a boosted range. The controller controls the variable intake and exhaust valve operating mechanisms so that a valve overlap period during which intake and exhaust valves open simultaneously is formed, when the engine operates in a low-speed boosted range of the boosted range where the engine speed is less than a reference speed. The controller controls the variable exhaust valve operating mechanism so that the open timing of the exhaust valve is more advanced when the engine operates in a high-speed boosted range of the boosted range where the engine speed is greater than or equal to the reference speed.

Atomic oxygen is provided for the purpose of promoting reliable ignition and smooth combustion in a spark ignition internal combustion engine is to disperse a low concentration of an atomic oxygen precursor, such as nitrous oxide (N.sub.2O), into the flammable mixture of air and gasoline vapor prior to the time of ignition. The introduction of N.sub.2O may take place in the intake manifold, in the stream of exhaust gas being returned as part of the EGR process, or directly into the combustion chamber (for example through a small orifice in the base of the spark plug or through a small nozzle located elsewhere in the cylinder head). Introduction of N.sub.2O directly into the combustion chamber may be continuous, or it may be pulsed so as to occur at the time of, or shortly before, spark ignition.