Nissan Motor Company Limited

National Institute of Information and Communications Technology, Incorporated

Masaaki Ashida

Kimiyoshi Nishizawa

Kouichi Mori

Shunichi Mitsuishi

Yoshinao Ugomori

Takao Inoue

Ritsuo Sato

Sunkee Yi

Shingo Saito

Katsuhiro Shibata

Hajime Yasuda

Masaru Iida

An exhaust manifold connected to exhaust ports of at least three straightly-arranged cylinders of an internal combustion engine is constructed by a primary exhaust pipe which extends from the foremost cylinder of the cylinders in the rearward direction of the engine along the direction of the straight arrangement of the cylinders and a plurality of secondary exhaust pipes which extend from the other cylinders except for the foremost cylinder to the primary exhaust pipe. The secondary exhaust pipes are collected to the primary exhaust pipe so that downstream end portions of the secondary exhaust pipes are wound into the center axis of the primary exhaust pipe at a plurality of points on the center axis, respectively.

Exhaust manifold for internal combustion engine

A light-waveform measuring device and method include a complex-refractive-index measuring device and a computer-program recording medium An electric field of an electromagnetic wave, in a light region having wavelengths smaller than those of electromagnetic waves in a near-infrared region, is measured, and time-varying waveforms are outputted. Gate-pulse-light generating means, measurement-light generating means and light-detecting means for detecting measurement light, are included, The measurement light is coherent light having a wavelength smaller than those of a near-infrared region. The gate pulse light is coherent light with a pulse width smaller than a period of the measurement light. A physical quantity, based on carriers generated from the measurement light and the gate pulse light is measured.

Optical waveform measurement device and measurement method thereof, complex refractive index measurement device and measurement method thereof, and computer program recording medium containing the program

In an exhaust manifold of a four-cylinder engine four cylinders of which line up in order of cylinder #, cylinder #, cylinder #and cylinder #, temperature rise performance of a manifold catalyst improves by shortening a total length of the exhaust manifold while preventing exhaust gas interference between the cylinders. Therefore, an exhaust manifold branch of cylinder #and an exhaust manifold branch of cylinder #in outward sides of the engine that are not fired in succession are made convergent with its convergence angle &#x3b8;being equal to or below 20 degrees to form a first convergent exhaust manifold branch and an exhaust manifold branch of cylinder #and an exhaust manifold branch of cylinder # 3 between the cylinder #and cylinder #that are not fired in succession are made convergent at a minimum distance having a laterally projected shape to form a second convergent exhaust manifold branch. The first and the second convergent exhaust manifold branches are thereafter convergent at a convergence angle &#x3b8;from 0 degrees to 20 degrees.

Exhaust manifold for four-cylinder engine

An internal-combustion engine is disclosed in which a pair of inlet valves and a pair of outlet valves are provided within the combustion chamber formed in each of a row of cylinders. A first ignition plug is disposed in the cylinder head within a central area of the combustion chamber in plan view. Second and third ignition plugs are disposed in the cylinder head at opposite peripheral portions of the combustion chamber positioned approximately along the first axis direction in plan view, the second and third ignition plugs are arranged so that the discharge electrode portions of the second and third ignition plugs being inclined inwardly of the combustion chamber in opposite directions and are substantially symmetrical relative with the first ignition plug in plan view. A line intersecting the discharge electrode portions of the second and third ignition plugs forms an oblique angle with the direction of the row of cylinders in plan view.

Internal-combustion engine and method of disposing ignition plug thereof

A hydrocarbon trapping layer () is formed by coating a hydrocarbon trapping material onto a carrier (A). A number of exhaust gas passages () are formed in the carrier (A) and a plurality of slits () are formed on the carrier (A) to cross the passages () in a transverse orientation. The slits () delay temperature increases in the downstream hydrocarbon trapping layer () and delay the release of trapped hydrocarbons therefrom. This is due to blocking the transmission of heat to the downstream hydrocarbon trapping layer () from the upstream hydrocarbon trapping layer (). The slits () further produce a turbulent flow in the flow of exhaust gas and promote diffusion of exhaust gas over the entire surface of the carrier (A).

Hydrocarbon trapping device

A fuel property determination system for an internal combustion engine is arranged to determine a fuel property indicative that fuel in use is heavy or light, on the basis of a degree of change of a revolution speed during a period from an expansion stroke of a first fuel injection cylinder at engine start to an expansion stroke of a final fuel injection cylinder in a first round as to all cylinders of the engine.

Fuel property determination system

An exhaust manifold of an engine exhaust apparatus includes a plurality of exhaust branches and a straight pipe section. The exhaust branches extend toward a confluence portion, from respective upstream ends to be connected with cylinders of an engine. The straight pipe section extends from the confluence portion toward a downstream end adapted to be connected to an exhaust purifying catalyst.

Engine exhaust apparatus

In an exhaust manifold of a four-cylinder engine four cylinders of which line up in order of cylinder #cylinder #cylinder #and cylinder #temperature rise performance of a manifold catalyst improves by shortening a total length of the exhaust manifold while preventing exhaust gas interference between the cylinders. Therefore, an exhaust manifold branch of cylinder #and an exhaust manifold branch of cylinder #in outward sides of the engine that are not fired in succession are made convergent with its convergence angle &#x3b8;being equal to or below 20 degrees to form a first convergent exhaust manifold branch and an exhaust manifold branch of cylinder #and an exhaust manifold branch of cylinder #between the cylinder #and cylinder #that are not fired in succession are made convergent at a minimum distance having a laterally projected shape to form a second convergent exhaust manifold branch. The first and the second convergent exhaust manifold branches are thereafter convergent at a convergence angle &#x3b8;from 0 degrees to 20 degrees.

The invention comprises at least two independent intake ports connected to a combustion chamber , two intake valves , and two exhaust valves . Upper and lower channels which are defined by a partition wall, and an intake control valve for opening and closing the lower side channel are provided in the interior of the first intake port . An intake control valve for opening and closing the first intake port is also provided. The invention further comprises a controller for controlling the opening and closing of the intake control valves and , and the degree of opening of these intake control valves and is controlled in accordance with the operating conditions.

Engine control apparatus

The invention comprises at least two independent intake ports connected to a combustion chamber , two intake valves , and two exhaust valves . A first fuel injection valve is provided in the first intake port and a second intake control valve is provided for opening and closing the second intake port . When the engine is in the cold condition, the second intake control valve is slightly opened and fuel is injected from the first fuel injection valve . Air-fuel mixture from the first intake port and a smaller amount of fresh air from the second intake port are introduced &lsqb;into the combustion chamber&rsqb;, and the overall air-fuel ratio inside the combustion chamber is controlled to become slightly lean.

An engine valve timing controller controls a hydraulically driven variable valve timing mechanism, based on coolant temperature and intake air temperature. If coolant temperature and intake air temperature at engine startup are at least equal to an operation assurance oil temperature and an absolute value of the difference between the two temperatures is less than or equal to a prescribed temperature, then oil temperature is determined to be at least as high as the operation assurance oil temperature. Thus, the valve timing mechanism operates after coolant temperature rises to a first operation permission coolant temperature that is a temperature at which increasing the amount of internal EGR by increasing the amount of valve overlap is permitted. If these conditions are not satisfied, then valve timing mechanism operates after coolant temperature rises to a second operation permission coolant temperature that is a temperature at which oil temperature is definitely at least equal to the operation assurance oil temperature.

Engine valve timing controller

A rotation speed is feedback controlled to a target rotation speed during idle running of an engine. When an automatic transmission is in a travel range, a brake is being operated and a vehicle speed is less than a predetermined value, the target rotation speed is decreased. A required vehicle creep force is different according to whether the vehicle has substantially stopped such as when it is waiting on a crossing, or whether it is moving in the idle running state as when it is being garaged or is following a vehicle in front of it in a traffic jam. By decreasing the target rotation speed according to the vehicle speed, an optimum creep force is obtained in both cases.

Growing community of inventors

Yokohama, Japan

Masaaki Ashida