This multi-cylinder engine intake structure is provided with a fresh air distribution chamber 20 into which a plurality of fresh air distribution openings 25 communicating with the individual intake ports 12 are opened, and a gas collection chamber 30. The gas collection chamber 30 includes a communication region 30B into which a first communication opening 7a communicating with the fresh air distribution chamber 20 is opened, a first mixture region 30A into which an air inlet 31a and an EGR gas inlet 32a are opened and which is positioned upstream of the communication region 30B in a flow direction of a mixture gas M of air A and EGR gas R, and a second mixture region 30C positioned downstream of the communication region 30B in the flow direction of the mixture gas M.

An engine structure configured to a control swirl in a diesel engine combustion chamber and a diesel engine assembly including the engine structure defines first and second intake ports and a connecting passage connecting the first and second intake ports. The first intake port is in fluid communication with the combustion chamber and configured to direct a first intake airflow into the combustion chamber, and the second intake port is in fluid communication with the combustion chamber and configured to direct a second intake airflow into the combustion chamber. The connecting passage connects the first intake port to the second intake port and is defined by the engine structure outside of the combustion chamber.

An intake system piping structure of an internal combustion engine includes an intake manifold connected to an end-side first cylinder and an end-side second cylinder which are provided farthest from each other in a cylinder bank in which a plurality of cylinders is placed in line, and an intercooler connected to the intake manifold. The intercooler is arranged in such a manner that a widthwise center of the intercooler on the side of an intake inlet and a widthwise center of the intercooler on the side of the manifold are offset to the side of the end-side second cylinder from a cylinder bank direction center line in center between an axial center line of the end-side first cylinder and an axial center line of the end-side second cylinder. Furthermore, the intercooler is also arranged in such a manner that an offset amount of the widthwise center of the intercooler on the side of the intake inlet from the cylinder bank direction center line is greater than an offset amount of the widthwise center of the intercooler on the side of the manifold from the cylinder bank direction center line.

An intake device for an internal combustion engine configures a flow passage for intake air that is drawn into combustion chambers. The intake device includes an intake manifold configuring multiple runners that respectively distribute intake air to multiple cylinders, a surge tank including a cavity that is connected to the runners and defines a convergence portion, a throttle body incorporating a throttle valve, and a connection pipe connecting the surge tank and the throttle body and configuring a curved flow passage extending between the throttle body and the surge tank. The connection pipe includes a partition plate that divides the curved flow passage into a circumferentially inner flow passage and a circumferentially outer flow passage.

There is provided an intake manifold of a multicylinder engine capable of facilitating homogenization of concentration distribution of EGR gas in intake air and distribution of EGR gas into respective cylinders. The intake manifold is configured such that an EGR gas guide portion is provided in an intake air introducing sleeve portion, the EGR gas guide portion includes an upstream EGR gas release port and a downstream EGR gas release port, the upstream EGR gas release port is provided on a side of a passage outlet of an EGR gas introducing passage, the downstream EGR gas release port is provided on an opposite side of a central portion of the intake air introducing sleeve portion from the upstream EGR gas release port, and the EGR gas introduced from the passage outlet of the EGR gas introducing passage into the intake air introducing sleeve portion is released from both of the upstream EGR gas release port and the downstream EGR gas release port into intake air passing through the central portion of the intake air introducing sleeve portion.

An engine device having gas injectors attached to an intake manifold fixed to a side surface of a cylinder head. A fuel gas injected from the gas injectors is premixed in the intake manifold, and the resulting gas is supplied to a plurality of cylinders and ignited by ignition devices. The intake manifold has a configuration in which a plurality of intake branch pipes communicating with the cylinders are branched from an intake collecting pipe at an air supply side. The intake branch pipes include bent portions. In the bent portions of the intake branch pipes, inside inner walls near the cylinder head are bent at an acute angle.

An engine provided with a combustion chamber includes a cylinder head in which a bulkhead is provided so as to extend toward the combustion chamber and an intake port is formed so as to bifurcate at the bulkhead, a bulkhead member that is provided with a partition plate intersecting the bulkhead and that divides the intake port into a first flow passage and a second flow passage with the partition plate provided between the first and second flow passages. The bulkhead of the cylinder head has a cutout formed and the partition plate of the bulkhead plate has an auxiliary wall that fills the cutout.

A control device for an internal combustion engine can prevent misfiring in cylinders of the internal combustion engine. When a deceleration request is issued while the engine load of an internal combustion engine is in a predetermined high-load region, and the vehicle is decelerated so that the engine load transitions from the high-load region to a low-load region to respond to the deceleration request, the control device performs control that continues a fuel supply from injectors of a first cylinder and a fourth cylinder, and cuts a fuel supply from injectors of a second cylinder and a third cylinder. Furthermore, condensed water generated in an intercooler is caused to flow between two guide devices provided at the bottom of a convergence portion of an intake manifold to thereby flow into intake branch pipes of the second cylinder and third cylinder.

There is provided an internal combustion engine in which respective combustion states of cylinders can be uniformized with a simple configuration. A central axis (CL1) of a connecting part (7) of one of air supply ports (5) inclines with a predetermined inclination angle in a direction away from an air supply inlet (3) with respect to a y direction orthogonal to an x direction in which an air supply manifold 1 extends, and an inclination angle of the connecting part (7) of the one of the air supply ports (5) is larger than an inclination angle of the connecting part (7) of other air supply ports (5) located on a side closer to the air supply inlet (3) than the one of the air supply ports (5).

An intake manifold includes a surge tank and left and right intake pipes containing one end sides each connected to the surge tank, and respectively extending to both side directions of the surge tank. A gas distribution passage portion to distribute exhaust gas to each of the left and right intake pipes is provided along a lower surface side of the surge tank and lower surface sides of the left and right intake pipes. An exhaust gas inlet and a gas distribution passage connected to the exhaust gas inlet are formed on the gas distribution passage portion. A communication hole to communicate an inside of each of the intake pipes and the gas distribution passage is formed on each of the left and right intake pipes.