Abstract: A piston includes a combustion chamber that is formed at a piston top surface and an oil gallery that is formed so as to surround the combustion chamber. Wall thickness from a sliding side surface of the piston to the oil gallery is set greater on a piston skirt side than on a piston top surface side.

Abstract: A piston includes a combustion chamber that is formed at a piston top surface and an oil gallery that is formed so as to surround the combustion chamber. Wall thickness from a sliding side surface of the piston to the oil gallery is set greater on a piston skirt side than on a piston top surface side.

Abstract: A common rail fuel injection system includes injectors having a fuel intake port and being provided for respective cylinders of a multi-cylinder diesel internal combustion engine, a common rail accumulating pressurized fuel, a high-pressure supply pump supplying high-pressure fuel, a fuel supply pipe causing the common rail and the high-pressure supply pump to communicate with each other. The fuel injection pipes communicating with pressure supply ports provided in the common rail and causing the injectors and the pressure supply ports to communicating with each other. The fuel injection pipes cause at least three injectors to communicate with one another in series. The number NP of pressure supply ports is less than the number PI of injectors, and supply of high-pressure fuel to the respective injectors for the cylinders is performed through fuel injection pipes of two lines.

Abstract: Fuel added to exhaust gas is uniformly afforded to catalytic surfaces of a NOx-adsorption reduction catalyst so that overall regeneration of the NOx-adsorption reduction catalyst proceeds efficiently. The invention is directed to an exhaust emission control device with the NOx-adsorption reduction catalyst incorporated in an exhaust pipe (exhaust flow passage) for guidance of the exhaust gas 9 from an engine 1 and with an fuel addition device (fuel addition means) 13 arranged for addition of fuel as a reducing agent to the exhaust pipe (exhaust flow passage) 11 upstream of the reduction catalyst 12 (exhaust flow passage) 11, a dispersion plate 15 being arranged between a position of adding the fuel by the fuel addition device 13 and the NOx-adsorption reduction catalyst 12 for dispersing the exhaust gas 9 to stimulate dispersion of the added fuel.