Abstract: Provided is a pre-chamber type diesel engine in which fuel injected from an injector mixes satisfactorily with air in a pre-combustion chamber. An injector injects fuel so as to be dispersed in a direction orthogonal to a vortex flow of air formed inside a pre-combustion chamber.

Abstract: Provided is a pre-chamber type diesel engine in which fuel injected from an injector mixes satisfactorily with air in a pre-combustion chamber. A corner space section, in which a forced vortex is formed by a flow of air advancing into a pre-combustion chamber from a main combustion chamber via a connecting hole during the compression stroke of a piston, is provided at a prescribed position between the line of extension of the connecting hole and the wall surface of the pre-combustion chamber.

Abstract: Provided is a subchamber diesel engine having excellent thermal efficiency and capable of appropriately controlling the ignition timing of fuel supplied to a combustion subchamber. A subchamber diesel engine according to the present invention comprises a main combustion chamber and a combustion subchamber communicated with each other by a communication hole, the diesel engine including: an electrically driven injector for injecting fuel into the combustion subchamber at a random timing; a fuel passage pipe connected to a fuel inlet of the injector; a fuel pump for supplying fuel to the fuel passage pipe; an engine operating state detector for detecting an engine operating state; and a controller, wherein the controller performs a preliminary fuel injection in the first half of an intake stroke, performs a main injection during a compression stroke, and after the main injection, performs an ignition control injection near a compression top dead center.

Abstract: Provided is a pre-chamber type diesel engine wherein the fuel system is not complicated, regardless of whether a regeneration function is provided. An injector is employed, which is able to inject fuel at a given timing by means of an electrical signal from a controller, and when a prescribed amount of particles have been trapped in a particle collection filter the injector carries out an additional fuel injection during the expansion stroke of a piston.

Abstract: An internal combustion engine including: an operating state detection unit that detects an operating state of the internal combustion engine; a fuel reforming unit configured to be supplied with a liquid fuel including hydrocarbon and generate a reformed fuel having an octane number larger than that of the supplied liquid fuel; a reformed fuel composition adjusting unit that adjusts the composition of the reformed fuel generated by the fuel reforming unit; and a control device that controls the composition of the reformed fuel by controlling the reformed fuel composition adjusting unit in accordance with the operating state detected by the operating state detection unit.

Abstract: An internal combustion engine including a fuel reformation unit that generates reformed fuel based on liquid fuel and higher in octane rating than the liquid fuel and introduces the generated reformed fuel to an output cylinder. The fuel reformation unit includes a first fuel reformer that includes a reciprocal mechanism where a piston reciprocates in a cylinder, a second fuel reformer that includes a reformation catalyst, and a reformed gas passage that connects the first and second fuel reformers together. First reformed gas discharged from the first fuel reformer is introduced to the second fuel reformer through the reformed gas passage.

Abstract: An internal combustion engine includes including a fuel reformation cylinder for reforming a fuel and an output cylinder for yielding an engine power by combusting a fuel or a reformed fuel, wherein at least a part of the surfaces constituting a volume-variable reaction chamber of the fuel reformation cylinder has a highly heat-insulative material.

Abstract: An internal combustion engine in which a fuel reforming operation in a fuel reformation cylinder is not executed when a gas temperature of a fuel reformation chamber at a time point when a piston in the fuel reformation cylinder reaches a compression top dead point is estimated to fall short of a reforming operation allowable lower limit gas temperature set based on a lower limit value of a reforming reaction enabling temperature. For example, fuel is supplied from an injector so that an equivalence ratio in the fuel reformation chamber is less than 1. Alternatively, the fuel supply from an injector is stopped. This way, a supply of non-reformed fuel from the fuel reformation cylinder to an output cylinder can be avoided, and knocking in the output cylinder can be avoided.

Abstract: An internal combustion engine including a fuel reformation cylinder for reforming a fuel and an output cylinder for yielding an engine power by combusting a fuel or a reformed fuel, wherein at least a part of the surfaces constituting a volume-variable reaction chamber of the fuel reformation cylinder has a highly heat-insulative material.

Abstract: An internal combustion engine in which a fuel reforming operation in a fuel reformation cylinder is not executed and a warming operation for raising the temperature of the fuel reformation cylinder is executed, when a gas temperature of a fuel reformation chamber at a time point when a piston in the fuel reformation cylinder reaches a compression top dead point is estimated to fall short of a reforming operation allowable lower limit gas temperature. For example, EGR gas is introduced to the fuel reformation chamber without cooling the EGR gas. Further, during a predetermined period from the expansion stroke to an exhaust stroke of an output cylinder, exhaust gas warming fuel is supplied to a combustion chamber. Further, the fuel is combusted in the fuel reformation chamber.

Abstract: An internal combustion engine in which when the gas temperature of a fuel reformation chamber when a piston in a fuel reformation cylinder reaches the compression top dead point is estimated to be equal to or higher than a soot generation lower limit temperature set according to an equivalence ratio of the fuel reformation chamber, a reaction gas temperature adjusting operation for suppressing or reducing an increase in the reaction gas temperature in the fuel reformation chamber is executed. Further, a closing timing of an air-intake valve is changed to reduce an effective compression ratio of the fuel reformation chamber.

Abstract: A control device to be applied to an internal combustion engine having a fuel reformation cylinder and an output cylinder, wherein the compression end gas temperature of the fuel reformation cylinder is adjusted by changing an EGR gas amount, an effective compression ratio, or a polytropic number according to an equivalence ratio in the fuel reformation cylinder so as to achieve a target concentration of a specific gas component in reformed fuel generated in the fuel reformation cylinder. The target concentration is defined according to a required engine power.

Abstract: An internal combustion engine in which a required reformed-fuel heat generation quantity (required output cylinder heat generation quantity) is calculated based on a required engine power and the thermal efficiency of an output cylinder. An estimated reformed fuel heat generation quantity is calculated based on the molar number of reformed fuel, mole fraction of each gas component in the reformed fuel, and heat generation quantity of each gas component in the reformed fuel. When a value resulting from subtracting the estimated reformed fuel heat generation quantity from the required reformed-fuel heat generation quantity is negative, a fuel reforming operation is not executed, assuming that there is a possibility that surplus reformed fuel may be generated. For example, a fuel supply from an injector to a fuel reformation chamber is stopped.

Abstract: An internal combustion engine in which an output from a fuel reformation cylinder is obtained based on a cylinder internal pressure and a rotational speed of the fuel reformation cylinder, and an output adjusting operation for adjusting an output from an output cylinder is executed so that a sum of the output from the fuel reformation cylinder and the output from the output cylinder matches with a required engine power. In this output adjusting operation, during a transient operation in which the required engine power is increased, the output from the output cylinder is increased by increasing the fuel supply amount to a combustion chamber. Then, the fuel supply amount to a fuel reformation chamber is gradually increased while the fuel supply amount to the combustion chamber is gradually reduced, so that a heat source is shifted from the fuel to the reformed fuel.

Abstract: An internal combustion engine in which when an ECU receives an engine stop command by an ON-operation of an engine stop switch, a supply of fuel from an injector to a fuel reformation chamber is stopped while a supply of fuel from an injector to a combustion chamber is continued, and the residual amount of a reformed fuel in passages is estimated, in this state. When the estimated residual amount reaches a predetermined amount or zero, the fuel supply from the injector to the combustion chamber is stopped, and an internal combustion engine is stopped.

Abstract: An internal combustion engine including: an operating state detection unit that detects an operating state of the internal combustion engine; a fuel reforming unit configured to be supplied with a liquid fuel including hydrocarbon and generate a reformed fuel having an octane number larger than that of the supplied liquid fuel; a reformed fuel composition adjusting unit that adjusts the composition of the reformed fuel generated by the fuel reforming unit; and a control device that controls the composition of the reformed fuel by controlling the reformed fuel composition adjusting unit in accordance with the operating state detected by the operating state detection unit.

Abstract: An internal combustion engine including a fuel reformation unit that generates reformed fuel based on liquid fuel and higher in octane rating than the liquid fuel and introduces the generated reformed fuel to an output cylinder. The fuel reformation unit includes a first fuel reformer that includes a reciprocal mechanism where a piston reciprocates in a cylinder, a second fuel reformer that includes a reformation catalyst, and a reformed gas passage that connects the first and second fuel reformers together. First reformed gas discharged from the first fuel reformer is introduced to the second fuel reformer through the reformed gas passage.

Abstract: A diagnosis device for a multi-cylinder internal combustion engine having an exhaust turbocharger, the device configured to diagnose a fuel combustion state in each one of cylinders in the internal combustion engine. The diagnosis device includes: a rotational speed detector configured to output a signal corresponding to a rotational speed of the exhaust turbocharger or a signal correlated to fluctuation in the rotational speed of the exhaust turbocharger, and a fuel combustion state diagnosis unit configured to diagnose unevenness in the fuel combustion states of the cylinders through a frequency analysis involving a fast Fourier transformation of a frequency characteristic of a signal output from the rotational speed detector.

Abstract: A control device (100) to be applied to an internal combustion engine (1) having a fuel reformation cylinder (2) and an output cylinder (3), wherein the compression end gas temperature of the fuel reformation cylinder (2) is adjusted by changing an EGR gas amount, an effective compression ratio, or a polytropic number according to an equivalence ratio in the fuel reformation cylinder (2) so as to achieve a target concentration of a specific gas component in reformed fuel generated in the fuel reformation cylinder (2). The target concentration is defined according to a required engine power.

Abstract: An internal combustion engine in which an output from a fuel reformation cylinder (2) is obtained based on a cylinder internal pressure and a rotational speed of the fuel reformation cylinder, and an output adjusting operation for adjusting an output from an output cylinder (3) is executed so that a sum of the output from the fuel reformation cylinder and the output from the output cylinder matches with a required engine power. In this output adjusting operation, during a transient operation in which the required engine power is increased, the output from the output cylinder is increased by increasing the fuel supply amount to a combustion chamber (33). Then, the fuel supply amount to a fuel reformation chamber (23) is gradually increased while the fuel supply amount to the combustion chamber is gradually reduced, so that a heat source is shifted from the fuel to the reformed fuel.