Abstract: A boosted engine is provided, which includes an engine body formed with a combustion chamber, a spark plug, a fuel injection valve, a booster, a boost controller, and a control unit including an operating range determining module and a compression end temperature estimating module. In a high load range, the fuel injection valve and the spark plug are controlled so that a mixture gas inside the combustion chamber starts combustion through flame propagation by ignition of the spark plug, and unburned mixture gas then combusts by compression ignition, and the boost controller is controlled to bring the booster into a boosting state. When a gas temperature inside the combustion chamber exceeds a given temperature at CTDC, the fuel injection valve is controlled so that a fuel injection end timing occurs on a compression stroke, and the spark plug is controlled so that the mixture gas is ignited after CTDC.

Abstract: The number of advance chambers is larger than the number of retard chambers in an intake variable valve timing (VVT), whereas the number of retard chambers is larger than the number of advance chambers in an exhaust VVT. Accordingly, with limitation of an oil pressure that can be used by the VVTs, a pumping loss in a transition period in which a valve overlap amount is changed by advancing or retarding a valve timing can be reduced.

Abstract: A turbocharger engine includes a dual stage turbocharger in which a first turbo unit is disposed on the upstream side of a second turbo unit on an exhaust passage. The turbocharger is disposed in such a manner that a second turbine shaft of the second turbo unit is far from an engine output shaft than a first turbine shaft of the first turbo unit in a plan view in an axis direction of a cylinder. Further, a second turbine is rotated clockwise around an axis thereof in a side view when the turbocharger is viewed from the side of the turbine, and an intra-turbine passage is disposed on the side of an engine body than the second turbine shaft.

Abstract: Disclosed herein is a fuel injection control device for a direct injection engine including an engine body (engine 1) and a fuel injection control unit (engine controller 100). The fuel injection control unit injects a fuel in a predetermined injection mode into a combustion chamber (17) such that while the engine body is warm, an air-fuel mixture layer and a heat-insulating gas layer, surrounding the air-fuel mixture layer, are formed in the combustion chamber at a point in time when an air-fuel mixture ignites, and changes the injection mode of the fuel into the combustion chamber such that while the engine body is cold, the lower the temperature of the engine body is, the thinner the heat-insulating gas layer becomes.

Abstract: The number of advance chambers is larger than the number of retard chambers in an intake variable valve timing (VVT), whereas the number of retard chambers is larger than the number of advance chambers in an exhaust VVT. Accordingly, with limitation of an oil pressure that can be used by the VVTs, a pumping loss in a transition period in which a valve overlap amount is changed by advancing or retarding a valve timing can be reduced.

Abstract: A homogeneous charge compression ignition engine includes a cylinder configured to accommodate a piston to be reciprocally movable, a fuel injection valve configured to inject fuel into the cylinder, a water injection valve configured to inject water into the cylinder, a fuel injection control module configured to inject fuel from the fuel injection valve into the cylinder at such a timing that a mixture of fuel and air is self-ignited in a latter stage of a compression stroke or in an initial stage of an expansion stroke, and a water injection control module configured to perform at least a basic water injection of injecting water from the water injection valve into the cylinder during a predetermined period, which starts concurrently with or after start of combustion by the self-ignition and which overlaps a combustion period.

Abstract: A boosted engine is provided, which includes an engine body formed with a combustion chamber, a spark plug, a fuel injection valve, a booster, a boost controller, and a control unit including an operating range determining module and a compression end temperature estimating module. In a high load range, the fuel injection valve and the spark plug are controlled so that a mixture gas inside the combustion chamber starts combustion through flame propagation by ignition of the spark plug, and unburned mixture gas then combusts by compression ignition, and the boost controller is controlled to bring the booster into a boosting state. When a gas temperature inside the combustion chamber exceeds a given temperature at CTDC, the fuel injection valve is controlled so that a fuel injection end timing occurs on a compression stroke, and the spark plug is controlled so that the mixture gas is ignited after CTDC.

Abstract: A control apparatus of an engine including a cylinder into which a piston is reciprocatably fitted is provided. The apparatus includes a fuel injector, a water injector, and a controller. The controller includes an engine load determining module for receiving a parameter and determining whether an engine operating range is within a low high load range or a high load range. Within the low load range, the controller controls the fuel injector to inject fuel into a center region of a combustion chamber. Within the high load range, the controller controls the fuel injector to inject the fuel in a period between a latter half of compression stroke and an early half of expansion stroke, and the water injector to inject supercritical water or subcritical water toward a crown surface of the piston in a period that is after the injection and before a mixture gas ignition.

Abstract: A controller injects fuel into a cylinder at a high fuel pressure of 30 MPa or higher, at least in a period between a terminal stage of a compression stroke and an initial stage of an expansion stroke when an operating mode of an engine body is at least in a first specified sub-range of a low load range, and at least in a second specified sub-range of a high load range. The controller sets an EGR ratio in the first specified sub-range to be higher than an EGR ratio in the second specified sub-range, and advances start of fuel injection in the first specified sub-range to start of fuel injection in the second specified sub-range.

Abstract: Disclosed herein is a fuel injection control device for a direct injection engine including an engine body (engine 1) and a fuel injection control unit (engine controller 100). The fuel injection control unit injects a fuel in a predetermined injection mode into a combustion chamber (17) such that while the engine body is warm, an air-fuel mixture layer and a heat-insulating gas layer, surrounding the air-fuel mixture layer, are formed in the combustion chamber at a point in time when an air-fuel mixture ignites, and changes the injection mode of the fuel into the combustion chamber such that while the engine body is cold, the lower the temperature of the engine body is, the thinner the heat-insulating gas layer becomes.

Abstract: An engine system is provided that includes a cylinder, an exhaust flow part, a purifying system, a water injector for injecting supercritical/subcritical water into the cylinder, a water supply passage connected with the water injector and for supplying the water, a first temperature increasing device disposed at a position of the exhaust flow part and for increasing a water temperature, and a second temperature increasing device including a part of the exhaust flow part and a part of the water supply passage, and for increasing a water temperature. The first device increases the water temperature when an exhaust gas temperature passing through the position of the exhaust flow part exceeds a reference temperature. The second device increases the water temperature when an exhaust gas temperature passing through the part of the exhaust flow part is above a water temperature passing the part of the water supply passage.

Abstract: A homogeneous charge compression ignition engine includes a cylinder configured to accommodate a piston to be reciprocally movable, a fuel injection valve configured to inject fuel into the cylinder, a water injection valve configured to inject water into the cylinder, a fuel injection control module configured to inject fuel from the fuel injection valve into the cylinder at such a timing that a mixture of fuel and air is self-ignited in a latter stage of a compression stroke or in an initial stage of an expansion stroke, and a water injection control module configured to perform at least a basic water injection of injecting water from the water injection valve into the cylinder during a predetermined period, which starts concurrently with or after start of combustion by the self-ignition and which overlaps a combustion period.

Abstract: 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.

Abstract: A control apparatus of a premixed charge compression ignition engine that includes an engine body having a cylinder and intake and exhaust passages, and causes a mixture gas to self-ignite inside the cylinder is provided. The apparatus includes a fuel injector for injecting fuel into the cylinder, a water injector for injecting supercritical water or subcritical water into the cylinder, an EGR passage for communicating the exhaust and intake passages and recirculating, as EGR gas, a portion of an exhaust gas discharged from the cylinder to the intake passage, an EGR valve for adjusting an EGR gas recirculation amount, and a controller. The controller includes an engine load determining module for receiving a parameter and determining whether an engine operating state is a first state where the engine load is below a switch load or a second state where the engine load is the switch load or above.

Abstract: A turbocharger engine includes a dual stage turbocharger in which a first turbo unit is disposed on the upstream side of a second turbo unit on an exhaust passage. The turbocharger is disposed in such a manner that a second turbine shaft of the second turbo unit is far from an engine output shaft than a first turbine shaft of the first turbo unit in a plan view in an axis direction of a cylinder. Further, a second turbine is rotated clockwise around an axis thereof in a side view when the turbocharger is viewed from the side of the turbine, and an intra-turbine passage is disposed on the side of an engine body than the second turbine shaft.

Abstract: When a catalytic converter in an exhaust passage is in an un-activated state, an intake air amount is increased, as compared to when the converter is in an activated state under the same engine operation condition, and an ignition timing is retarded beyond a TDC of a compression stroke. The ignition timing is set such that a retard amount thereof from the TDC becomes larger as an external load causing a rotational resistance of an engine becomes lower. A valve opening start timing of an exhaust valve is set such that, when the external load is lower than a given reference load, the valve starts opening, before an in-cylinder pressure reaches a peak, according to combustion of an air-fuel mixture ignited at the above ignition timing, in a subsequent expansion stroke, wherein the in-cylinder pressure is based on an assumption that the valve is maintained in a valve-closed state.

Abstract: A spark-ignition direct injection engine is provided. The engine includes an engine body, a fuel injection valve, a fuel pressure setting mechanism, an ignition plug, and a controller. The controller switches between a compression-ignition mode where the engine body is operated to perform compression-ignition combustion and a spark-ignition mode where the engine body is operated to perform spark-ignition combustion. Immediately after switching from the spark-ignition mode to the compression-ignition mode, the controller operates the engine body in a compression-ignition initial mode where the fuel pressure is set to be 30 MPa or above and the fuel injection valve is controlled to perform the fuel injection in a period from a late stage of the compression stroke to an early stage of the expansion stroke so that the gas mixture self-ignites to combust.

Abstract: An engine system is provided that includes a cylinder, an exhaust flow part, a purifying system, a water injector for injecting supercritical/subcritical water into the cylinder, a water supply passage connected with the water injector and for supplying the water, a first temperature increasing device disposed at a position of the exhaust flow part and for increasing a water temperature, and a second temperature increasing device including a part of the exhaust flow part and a part of the water supply passage, and for increasing a water temperature. The first device increases the water temperature when an exhaust gas temperature passing through the position of the exhaust flow part exceeds a reference temperature. The second device increases the water temperature when an exhaust gas temperature passing through the part of the exhaust flow part is above a water temperature passing the part of the water supply passage.

Abstract: A variable cylinder engine is provided. The engine includes an engine body having a plurality of cylinders, a cooling mechanism for cooling the engine body by using a coolant, and a controller for controlling a temperature of the coolant and changing the number of active cylinders according to an operating state of the engine. The controller reduces the number of active cylinders in a reduced-cylinder operating range set within a partial engine load range, and expands the reduced-cylinder operating range to a higher engine load side as the coolant temperature becomes lower.

Abstract: A control apparatus of an engine including a cylinder into which a piston is reciprocatably fitted is provided. The apparatus includes a fuel injector for injecting fuel into the cylinder, a water injector for injecting supercritical or subcritical water into the cylinder, and a controller. The controller includes an operating range determining module for receiving a parameter and determining whether an engine operating range is within a water injection range. Within the water injection range, the controller controls the fuel injector to inject a portion of the fuel on an intake stroke or in an early half of compression stroke, and the water injector to inject the water toward a piston crown surface in a period that is between a latter half of the compression stroke and an early half of expansion stroke, after the fuel injection, and before a mixture gas is ignited inside the cylinder.