Abstract: The outlet duct extending outward from the air cleaner case is also extended inward into the air cleaner case with the same inner diameter such that the length of the part extending into the air cleaner is 10% to 25% of the axial length of the air cleaner element. By this, the distance from the opening of the outlet duct in the air cleaner case to the air flow sensor located in a downstream zone can be increased in an automobile engine, turbulence in the intake air flow can be considerably weakened at the air flow sensor, and air flow measurement not fluctuating widely can be obtained with an air flow measuring device having the same calibration program even when an air cleaner element of different type, i.e. of single type or double type, is used in an air cleaner case of the same design.

Abstract: To protect a drive unit in a fluid valve assembly from impurities over a long term by preventing entrance of such impurities to the drive unit, a seal structure the sealing performance of which is hardly reduced is adopted around a moving part of the fluid valve assembly. The fluid valve assembly is provided with a valve member displaceably arranged in a flow passage through which a fluid is allowed to pass, a drive unit arranged outside the flow passage, a connecting member extending through a bore formed in a wall of the flow passage and connected at its end thereof to the valve member and at its opposite end to the drive unit, and a seal member arranged in gas- or water-tight relations with the wall of the flow passage and the connecting member and made of a flexible material such that the seal member does not interfere with a displacement of the valve member when the valve member is driven by the drive unit.

Abstract: A failure detection apparatus for an internal combustion engine includes failure detecting means (S22–S30) for detecting abnormality of fresh air quantity detecting means (air flow sensor) based on the result of comparison between a fresh air quantity detected by the fresh air quantity detecting means (air flow sensor) and a fresh air quantity reference value set by fresh air quantity reference value setting means (S20), and a supercharger equipped with variable nozzles/vanes. The fresh air quantity reference value setting means sets the reference value (S16) in accordance with not only the operating state (engine speed Ne, fuel injection quantity Qf, etc.) of the engine but also a target vane opening set for the variable nozzles/vanes of the supercharger by target vane opening setting means (S12, S14).

Abstract: A failure detection apparatus for an internal combustion engine includes failure detecting means (S22-S30) for detecting abnormality of fresh air quantity detecting means (air flow sensor) based on the result of comparison between a fresh air quantity detected by the fresh air quantity detecting means (air flow sensor) and a fresh air quantity reference value set by fresh air quantity reference value setting means (S20), and exhaust flow rate adjusting means. The fresh air quantity reference value setting means sets the reference value (S16) in accordance with not only the operating state (engine speed Ne, fuel injection quantity Qf, etc.) of the engine but also a target adjustment amount (target throttle valve opening) set for the exhaust flow rate adjusting means by target adjustment setting means (S12, S14).

Abstract: The outlet duct extending outward from the air cleaner case is also extended inward into the air cleaner case with the same inner diameter such that the length of the part extending into the air cleaner is 10% to 25% of the axial length of the air cleaner element. By this, the distance from the opening of the outlet duct in the air cleaner case to the air flow sensor located in a downstream zone can be increased in an automobile engine, turbulence in the intake air flow can be considerably weakened at the air flow sensor, and air flow measurement not fluctuating widely can be obtained with an air flow measuring device having the same calibration program even when an air cleaner element of different type, i.e. of single type or double type, is used in an air cleaner case of the same design.

Abstract: To protect a drive unit in a fluid valve assembly from impurities over a long term by preventing entrance of such impurities to the drive unit, a seal structure the sealing performance of which is hardly reduced is adopted around a moving part of the fluid valve assembly. The fluid valve assembly is provided with a valve member displaceably arranged in a flow passage through which a fluid is allowed to pass, a drive unit arranged outside the flow passage, a connecting member extending through a bore formed in a wall of the flow passage and connected at its end thereof to the valve member and at its opposite end to the drive unit, and a seal member arranged in gas- or water-tight relations with the wall of the flow passage and the connecting member and made of a flexible material such that the seal member does not interfere with a displacement of the valve member when the valve member is driven by the drive unit.

Abstract: A failure detection apparatus for an internal combustion engine includes failure detecting means (S22-S30) for detecting abnormality of fresh air quantity detecting means (air flow sensor) based on the result of comparison between a fresh air quantity detected by the fresh air quantity detecting means (air flow sensor) and a reference value for the fresh air quantity set by fresh air quantity reference value setting means (S20), and an EGR device (EGR passage, EGR valve, target opening setting means, EGR valve control means). The fresh air quantity reference value setting means sets the reference value (S16) in accordance with not only the operating state (engine speed Ne, fuel injection quantity Qf, etc.) of the engine but also a target EGR valve opening set by target opening setting means (S12, S14).

Abstract: A failure detection apparatus for an internal combustion engine includes failure detecting means (S22-S30) for detecting abnormality of fresh air quantity detecting means (air flow sensor) based on the result of comparison between a fresh air quantity detected by the fresh air quantity detecting means (air flow sensor) and a fresh air quantity reference value set by fresh air quantity reference value setting means (S20), and exhaust flow rate adjusting means. The fresh air quantity reference value setting means sets the reference value (S16) in accordance with not only the operating state (engine speed Ne, fuel injection quantity Qf, etc.) of the engine but also a target adjustment amount (target throttle valve opening) set for the exhaust flow rate adjusting means by target adjustment setting means (S12, S14).

Abstract: A failure detection apparatus for an internal combustion engine includes failure detecting means (S22-S30) for detecting abnormality of fresh air quantity detecting means (air flow sensor) based on the result of comparison between a fresh air quantity detected by the fresh air quantity detecting means (air flow sensor) and a fresh air quantity reference value set by fresh air quantity reference value setting means (S20), and a supercharger equipped with variable nozzles/vanes. The fresh air quantity reference value setting means sets the reference value (S16) in accordance with not only the operating state (engine speed Ne, fuel injection quantity Qf, etc.) of the engine but also a target vane opening set for the variable nozzles/vanes of the supercharger by target vane opening setting means (S12, S14).

Abstract: The present invention relates to an EGR control unit and EGR control method for controlling an EGR adjusting apparatus, and it is an object of the invention to calculate an EGR rate at a low cost and to control an operation of the EGR apparatus with high accuracy. The EGR control unit is made up of temperature detecting devices detect in-passage temperature at least two of an intake passage, an atmospheric air introduction passage located on the upstream side of the intake passage and communicated with the atmosphere and an EGR passage, an actual EGR rate calculating device for calculating a rate of an exhaust gas to an intake gas in an internal combustion engine on the basis of information on temperatures detected by the temperature detecting devices, and an EGR controller for controlling the EGR adjusting device through the use of the actual EGR rate calculated by the actual EGR rate calculating device.

Abstract: A failure detection apparatus for an internal combustion engine includes failure detecting means (S22-S30) for detecting abnormality of fresh air quantity detecting means (air flow sensor) based on the result of comparison between a fresh air quantity detected by the fresh air quantity detecting means (air flow sensor) and a reference value for the fresh air quantity set by fresh air quantity reference value setting means (S20), and an EGR device (EGR passage, EGR valve, target opening setting means, EGR valve control means). The fresh air quantity reference value setting means sets the reference value (S16) in accordance with not only the operating state (engine speed Ne, fuel injection quantity Qf, etc.) of the engine but also a target EGR valve opening set by target opening setting means (S12, S14).

Abstract: An ECU preliminarily obtains a target supercharging pressure determined based on an engine rotational speed and an engine load, and stores the target supercharging pressure value. The ECU commands a flow passage area changing unit to set an exhaust gas flow passage area to the maximum flow passage area or the minimum flow passage area, and judges the abnormality of a supercharger by comparing supercharging pressure detected by a supercharging pressure sensor and the stored target supercharging pressure.

Abstract: An ECU preliminarily obtains a target supercharging pressure determined based on an engine rotational speed and an engine load, and stores the target supercharging pressure value. The ECU commands a flow passage area changing unit to set an exhaust gas flow passage area to the maximum flow passage area or the minimum flow passage area, and judges the abnormality of a supercharger by comparing supercharging pressure detected by a supercharging pressure sensor and the stored target supercharging pressure.

Abstract: The present invention relates to an EGR control unit and EGR control method for controlling an EGR adjusting apparatus, and it is an object of the invention to calculate an EGR rate at a low cost and to control an operation of the EGR apparatus with high accuracy. The EGR control unit is made up of temperature detecting devices detect in-passage temperature at least two of an intake passage, an atmospheric air introduction passage located on the upstream side of the intake passage and communicated with the atmosphere and an EGR passage, an actual EGR rate calculating device for calculating a rate of an exhaust gas to an intake gas in an internal combustion engine on the basis of information on temperatures detected by the temperature detecting devices, and an EGR controller for controlling the EGR adjusting device through the use of the actual EGR rate calculated by the actual EGR rate calculating device.

Abstract: A recirculating exhaust gas cooling device is provided for cooling exhaust gas of a vehicle engine while the exhaust gas is recirculating through an EGR system designed to lower NOx emission levels. The cooling device includes a housing in which an exhaust gas recirculation passage and a cooling fluid passages are located next to each other, to extend in parallel with each other, and a heat-exchange core member rotatably provided in the housing and defining a multiplicity of passages that extend in substantially parallel with a rotational axis of the core member, and a rotating mechanism that rotates the core member. The multiple passages of the core member communicate with both of the exhaust gas recirculation passage and the cooling fluid passage. With the core member being rotated, EGR gas passing through the exhaust gas recirculation passage is cooled by a part of the passages of the core member that has been cooled by a cooling fluid passing through the cooling fluid passage.