Mazda Motor Corporation

Mitsunori Wasada

Takashi Youso

Kazuhiro Nagatsu

Atsushi Inoue

Jiro Kato

Keiji Araki

Junichi Taga

Naohiro Yamaguchi

Hidesaku Ebesu

Satoshi Imamura

Ken Yoshida

Taketoshi Yamauchi

Shuhei Tsujita

Tatsuya Koga

Toshimasa Kotani

Yasushi Nakahara

Tatsuya Fujikawa

Masayoshi Higashio

Takashi Kaminaga

Ryotaro Nishida

Kouichi Shimizu

Takaaki Nagano

Tsuyoshi Yamamoto

Ryo Yamamoto

Haruna Yanagida

Tsukasa Hoshino

Kensuke Ashikaga

Mitsutaka Yamaya

Eiji Takano

Toshihiko Hirata

Hiroaki Abe

Hisayuki Yamane

Hirofumi Shinohara

Yoshihiro Hamazume

Tadasu Hashiguchi

Masafumi Nakano

Tadatomo Toda

Kenji Takami

An engine is provided, which includes an engine body including a cylinder provided with intake and exhaust ports and intake and exhaust valves, intake and exhaust passages, a turbocharger including a turbine provided to the exhaust passage and a compressor provided to the intake passage, and a variable phase mechanism configured to change open/close timings of the intake valve while maintaining an open period of the intake valve at a 270&#xb0; C.A or larger. A geometric compression ratio of the cylinder is 11:1 or higher. In a high-load range, the variable phase mechanism sets the intake valve close timing to be after an intake BDC and to make a ratio of a retarded amount of the intake closing to the geometric compression ratio be 4.58 or above and 6.67 or below, and sets the intake valve open timing to be before a close timing of the exhaust valve.

Engine

An engine is provided, which includes an engine body including a plurality of cylinders, each of the cylinders being provided with an intake port, an exhaust port, an intake valve, and an exhaust valve, an intake passage and an exhaust passage connected to the engine body, and a turbocharger including a turbine provided to the exhaust passage and a compressor provided to the intake passage. A geometric compression ratio of the cylinder is 11:1 or higher. An open period of the intake valve is a range of 270&#xb0; or larger by a crank angle. The exhaust passage includes a plurality of independent exhaust passages, each communicating with the exhaust port of one cylinder or with the exhaust ports of two or more cylinders of which timings of exhaust strokes are discontinuous from each other, and connecting the engine body to the turbine.

An exhaust gas recirculation (EGR) passage is connected with an intake passage (a bypass passage bypassing a supercharger) of an engine. The EGR passage includes, in a position close to a connection port to the intake passage, an expanding portion in which a passage cross-sectional area expands and which lowers a flow speed of EGR gas so as to reduce an uneven flow, in the connection port, of the EGR gas flowing into the intake passage.

Air intake device for engine

The present disclosure aims to improve circulation of intake air and distribution of bypass intake air to cylinders, while reducing an increase in the overall height of an engine. A supercharger extends along a cylinder bank at a side of a surge tank extending along the cylinder bank. A bypass pipe branching off from an upstream intake pipe configured to introduce the intake air into the supercharger extends along the cylinder bank above the supercharger. A downstream side intake pipe configured to guide the intake air from the supercharger to the surge tank extends downward from the supercharger. The downstream intake pipe is, in a U-shape as viewed along the cylinder bank, connected to the surge tank.

Engine with supercharger arrangement

The present disclosure aims to stabilize, in an engine with a supercharger, a detection result of an intake air temperature sensor interposed between the supercharger and an intercooler. A gas outlet of a supercharger and a gas inlet of an intercooler are connected together via a second passage. The second passage includes, in its middle position, a narrow region with a smaller cross-sectional area than the part of the second passage extending from an upstream end of the second passage to the middle position. The narrow region is provided with the intake air temperature sensor configured to detect the gas temperature in the narrow region.

Structure of mounting intake air temperature sensor of engine with supercharger

Injection of the fuel by the injectorcreates a gas flow in the combustion chamber. The gas expands in a radial fashion from an axis of a cylinder toward a radial outside of the cylinder, and then flows from the radial outside along the cylinder head bottom facetoward the axis of the cylinder. The spark plughas a gap positioned away from the axis of the cylinder toward the radial outside of the cylinder at a predetermined distance, and placed radially inwardly from a position opposite a rim of an opening of the cavityA side electrode extends to be oriented in a direction perpendicular to the flow of the gas along the cylinder head bottom face. The gap has a center positioned near the cylinder head bottom face, and closer to an interior of a combustion chamber than to the cylinder head bottom face.

Internal combustion engine

A control device of a compression-ignition engine is provided. The device includes an engine having a cylinder, a fuel injection valve for injecting a fuel, an exhaust valve mechanism for switching an operation mode of an exhaust valve between a normal mode and an open-twice mode, a throttle valve disposed on an intake passage, and a controller for operating the engine by compression-ignition combustion of mixture gas inside the cylinder at least within a low engine load range. The controller suspends the fuel injection by the fuel injection valve when a predetermined fuel cut condition is met while the engine decelerates, and the controller fully closes the throttle valve and controls the exhaust valve mechanism to operate in the open-twice mode during the fuel cut. When a predetermined fuel resuming condition is met, the controller restarts the fuel injection, opens the throttle valve, and causes the compression-ignition combustion.

Control device of compression-ignition engine

A control device of a compression-ignition engine is provided. The control device includes the engine having a cylinder, an exhaust gas recirculation system for introducing exhaust gas into the cylinder, and a controller for operating the engine by compression-ignition combustion of mixture gas inside the cylinder within a predetermined compression-ignitable range on a low engine load side. Within the compression-ignitable range, the controller sets an EGR ratio higher as the engine load becomes lower, and the controller sets the EGR ratio to a predetermined highest EGR ratio when the engine load is at a specific load that is on the low engine load side within the compression-ignitable range. When the engine load is lower than the specific load, the controller sets the EGR ratio to be lower than the highest EGR ratio.

The axial line of an intake valve is inclined, and a gap between a piston crown surface and a valve head of the intake valve expands in accordance with the approach of the crankshaft axis. A relationship of G&#x3e;Gis fulfilled, where Gstands for a minimum gap between the lower surface of the cylinder head that is positioned between the intake valve and the exhaust valve facing the intake valve, with the crankshaft axis being interposed therebetween, and the piston crown surface in a top dead center, and Gstands for a gap at a position that is the closest to the crankshaft axis, from among the gaps between the lower surface of the valve head of the intake valve and the piston crown surface at a center timing of a valve overlap period in which the intake valve and the exhaust valve are both open.

Combustion chamber structure for engine

Growing community of inventors

Hiroshima, Japan

Mitsunori Wasada