An abnormality determination device of an internal combustion engine in which a breather line connects an intake-air path positioned upstream from a forced-induction system and a crankcase includes an intake-air flow rate sensor that detects an intake air flow rate in the intake-air path, a pressure sensor that detects a pressure in the breather line, and an abnormality determination unit that determines abnormality of the breather line. The abnormality determination unit compares the pressure and a threshold for each flow rate, integrates a number of times the pressure becomes the threshold or greater, and determines abnormality of the breather line when an integrated value becomes a predetermined value or greater within a predetermined time. The abnormality determination unit calculates a weight coefficient for each flow rate and assigns weights to a number of times the pressure becomes the threshold or greater by using the weight coefficient.

Flow control devices herein have a housing defining a plurality of parallel conduits. The first conduit has a normally closed check valve defined to open under a first preselected pressure differential controlling flow through the first conduit in a first direction of flow. The second conduit has a normally neutral check valve defined to open under a second preselected pressure differential in a second direction of flow that is opposite the first direction of flow. The third conduit defines a restriction profile, i.e., has a restrictor, having a third preselected pressure differential. The flow control devices are included as part of an engine system, more specifically a crankcase ventilation breach detection system.

A breach detection system for an internal combustion engine having a crankcase, an intake manifold, a positive crankcase ventilation valve, a crankcase ventilation tube with a flow control system therein, and a pressure sensor between the flow control system and the crankcase. The flow control system subdivides the crankcase ventilation tube into a plurality of parallel conduitsa first conduit having a normally closed check valve that opens under a first preselected pressure drop in a first direction from the air intake to the crankcase, and a second conduit having either a second check valve that opens under a second preselected pressure drop in a second direction opposite the first direction or a restriction profile having a third preselected pressure drop that is the same in both the first and second direction. When the pressure sensor detects no pressure drop there is a breach in the system.

Methods and systems are provided for enhancing crankcase ventilation in a boosted engine. During boosted conditions, a crankcase may be ventilated via vacuum generated at an aspirator coupled in a compressor bypass passage. However, when the aspirator is plugged, pressure in the crankcase may be relieved by flowing crankcase gases through an aspirator bypass passage.

A pressure-limiting valve for use in a gas line conveying a gas that includes aerosols. The pressure-limiting valve has a movable valve body, a valve seat, and a compressible coalescing medium placed therebetween. The valve body has passages and nozzle openings and the valve seat has through-holes. In the closed position, the valve functions in separator mode and in the fully open position, in impactor mode. The pressure-limiting valve according to the invention provides a more sensitive response to varying flow conditions, due to deviating surface profiles of the valve seat and coalescing medium, which provide intermediate stages of separator and impactor modes as a function of the volume of flow.

An automobile power system in a vehicle may include an intake pipe supplying external air to an engine supplying power to driving wheels, a canister connected with a fuel tank to absorb evaporation gas produced in the fuel tank, an active purging system compressing and supplying the evaporation gas absorbed in the canister to the intake pipe, a diverging line extending from the active purging system to the engine, a diverging valve mounted on the diverging line, and a starting motor rotating a crankshaft when the engine is started. In addition, the evaporation gas absorbed in the canister is supplied to the engine through the diverging line before the engine is restarted, and then the starting motor is operated.

A unit (10) for the regulation or control of a fluid pressure, having at least one housing section (13, 14) and a switching film (22) connected to the at least one housing section (13, 14) for switching at pressure differentials relative to an ambient pressure acting on the switching film (22), and for the regulation, release or blocking of a flow of the fluid between an inlet (28) and a discharge (30) for the fluid. The switching film (22) is made out of a polymer material having fluorine and carbon, in particular a thermoplastic having fluorine and carbon. In this arrangement, a hole cross-section (40) of the at least one housing section (13, 14) is closed off by the switching film (22).

A positive crankcase ventilation (PCV) system includes: an oil separator separating oil from blow-by gases; a PCV valve allowing the blow-by gases from which the oil has been separated by the oil separator to flow into intake ports of a cylinder head; a PCV passage vertically extending from the PCV valve; a PCV chamber connected to the PCV passage; and a plurality of bypass passages branching off from the PCV chamber to the intake ports, respectively.

This blow-by gas recirculation device for an internal combustion engine is provided with a vacuum pump which supplies negative pressure to a brake booster and usable for recirculation of blow-by gas to an intake passage. This device includes: a PCV device for recirculating blow-by gas in a crankcase to the intake passage; a ventilation shortage region determination unit which determines whether or not an operational region of the engine is a PCV ventilation flow rate shortage region; and a brake negative pressure determination unit which determines whether or not the negative pressure of the brake booster is secured. The vacuum pump ventilates blow-by gas in the crankcase only when the determination units determines that the operational region is the PCV ventilation flow rate shortage region and that the negative pressure is secured. This reduces a contact risk of blow-by gas with engine oil, and inhibits the degradation of the oil.

Provided is a PCV valve assembly that includes a fluidic geometry that allows for the flow of combustion fluid/gas to flow between an inlet and an outlet and switch between two modes of operation, (i) a radial or high flow mode, and (ii) a tangential or low flow mode, as dictated during the operation of the engine. At low vacuums, the fluidic equipped PCV valve assembly has been tuned to operate in the radial mode producing high flow rates due to low flow resistance. As vacuum increases, the PCV valve assembly is tuned to automatically switch modes. This may be enabled due to the shape of the fluidic geometry and the bypass channel which is adapted to vary the amount of flow between a first and a second control ports. The bypass channel allows the geometric fluidic pattern to switch between the high flow mode and the low flow mode.