Mazda Motor Corporation

Yohei Suzuki

Yasushi Nakahara

Tsuyoshi Yamamoto

Yuya Honda

Michiharu Kawano

Kento Onishi

Toshiaki Nishimoto

Hiroshi Takahashi

Yoshitaka Wada

Yuki Nabetani

A cylinder head of a multi-cylinder engine is provided, the cylinder head including a plurality of ceiling parts for respective cylinders, and a water jacket. Each ceiling part is connected to an intake port including a primary port and a secondary port aligned in a cylinder-row direction, and is attached with an in-cylinder pressure sensor. A plug is attached to a hollow part of the cylinder head corresponding to a core print provided to a core of the water jacket, and is disposed at a position corresponding to a location between certain cylinders. The in-cylinder pressure sensor is attached at a position on an opposite side from the plug with respect to a cylinder center axis in the cylinder-row direction. Positions of the primary and secondary ports connected to each ceiling part are interchanged in the cylinder-row direction according to the position of the in-cylinder pressure sensor.

Engine cylinder head

In an engine (), an ignition plug () is arranged between a first intake port () and a second intake port (). In a case where a downstream end portion () of the second intake port () is divided into a first intake port () side and an opposite first intake port () side, an inner wall surface () of an opposite first intake port () side portion extends in a direction toward the first intake port () as extending from an upstream side to a downstream side of the second intake port ().

Intake port structure for internal combustion engine

In an engine (), when an intake valve () opens, a downstream end portion () of a first intake port () extends to direct to between a shade back () positioned on a cylinder axis (C) side with respect to a valve stem () and a ceiling surface () facing the shade back (). As viewed in a section perpendicular to a direction perpendicular to an intake air flow direction, a second intake port side inner wall surface () at the downstream end portion () of the first intake port () curves apart from a second intake port () in a direction from an exhaust side to an intake side as compared to the shape of an opposite second intake port side inner wall surface () mirror-reversed to a second intake port () side.

A hydraulic supply device for a valve stopping mechanism includes: a specific hydraulic oil supply passage which constantly supplies hydraulic oil, a valve stopping mechanism incorporated in a cylinder head, and configured to stop at least one of an intake valve and an exhaust valve, a valve stopping oil passage which supplies hydraulic oil to the valve stopping mechanism, a control valve which controls the supply of hydraulic oil to the valve stopping oil passage, and a communication oil passage which communicates between the valve stopping oil passage and the specific hydraulic oil supply passage, and provided with a restrictor therebetween. The specific hydraulic oil supply passage is connected to an oil supply portion for a portion to be lubricated or for a portion to be cooled in the engine at a position downstream of a connection position with respect to the communication oil passage in an oil supply direction.

Hydraulic supply device for valve stopping mechanism

An intake device of an engine having cylinders is provided. The intake device includes a cylinder head formed with two intake ports per cylinder, and a forced induction system. One of the two intake ports is designed to have a smaller passage cross-sectional area at a throat portion thereof than that of the other intake port, and to cause a strength of a tumble flow strength of intake air formed within a combustion chamber to be stronger when a flow of the intake air into the combustion chamber is assumed to be caused only from the one of the two intake ports, than only from the other intake port. A tumble ratio of the intake air flow within the combustion chamber is a predetermined value or greater when the intake air is forcibly induced and flows into the combustion chamber from the two intake ports.

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Hiroshima, Japan

Yohei Suzuki