Abstract: A system operable to control an exhaust gas omission of an engine, includes a catalytic converter; a fuel cutter, a change executor, a correlation value provider, an adjuster, and a controller. The change executor is operable to execute changing of an air-fuel ratio of the engine to a rich after the fuel supply is once stopped by the fuel cutter and then resumed. The correlation value provider is operable to provide a correlation value correlated to a change amount of the air-fuel ratio caused by the change executor based on a driving condition of the engine. The adjuster is operable to adjust the correlation value based on a parameter indicative of a capability of the catalytic converter. The controller is operable to cause the change executor to execute the changing based on the adjusted correlation value.

Abstract: When the first fuel injection is performed after reversion from the fuel cut, the fuel pulse width Ka·INJ.PW is set so that a fuel supply amount is greatly increased in relation to an intake air amount, and the ignition timing is set to the first retarded ignition timing ?a. When the second and subsequent fuel injections are performed, the fuel pulse width Kb·INJ.PW that is smaller in increase width of fuel is set, and the ignition timing is set to the second retarded ignition timing ?b that has a retardation amount smaller than that of the first retarded ignition timing ?a.

Abstract: In a fuel cut period, an adsorbed CO quantity calculation section calculates the amount CATco of CO adsorbed on a catalyst, and an exhaust O2 quantity calculation section calculates the amount GASo2 of O2 in exhaust gases. CO oxidation reaction heat ?Hr produced when the calculated amount CATco of absorbed CO reacts with the calculated amount GASo2 of O2 in the exhaust gases is calculated by a ?Hr calculation section, and used in estimation of the temperature of the catalyst.

Abstract: When the first fuel injection is performed after reversion from the fuel cut, the fuel pulse width Ka·INJ.PW is set so that a fuel supply amount is greatly increased in relation to an intake air amount, and the ignition timing is set to the first retarded ignition timing ?a. When the second and subsequent fuel injections are performed, the fuel pulse width Kb·INJ.PW that is smaller in increase width of fuel is set, and the ignition timing is set to the second retarded ignition timing ?b that has a retardation amount smaller than that of the first retarded ignition timing ?a.

Abstract: An engine control device for detecting misfire of an engine. Based on a detected crank angle of the engine, an angular velocity at a first crank angle at which the engine speed is close to a minimum within one combustion cycle of each cylinder is calculated as a pre-combustion angular velocity, and an angular velocity at a second crank angle at which the engine speed is close to a maximum within the same combustion cycle is calculated as a post-combustion angular velocity. An amount of rotation variation caused between the first and second crank angles is calculated based on the pre-combustion and post-combustion angular velocities of the same combustion cycle, and is compared with a predetermined misfire criterion to determine whether or not misfire has occurred. When misfire is detected, a required operation is performed, for example, a warning lamp is turned on or the fuel supply quantity is increased.

Abstract: An air-fuel ratio control apparatus for a multiple cylinder engine, having catalytic converters and air-fuel ratio sensors in an exhaust manifold, comprises exhaust air-fuel ratio variation determining means which determines a variation in exhaust air-fuel ratio between one cylinder and other cylinders in one cylinder group when an exhaust air-fuel ratio on one of the rich side and the lean side with respect to a predetermined value is detected as to the one cylinder twice in succession, an exhaust air-fuel ratio on the other one of the rich side and the lean side from the exhaust air-fuel ratio of the one cylinder, and combustion air-fuel ratio control means which feedback-compensates the quantity of fuel injected into the one cylinder, and feedback-compensated the quantity of fuel injected into the other cylinder in a direction opposite to the direction in which the quantity of fuel injected into the one cylinder is compensated.

Abstract: An engine control device for detecting misfire of an engine. Based on a detected crank angle of the engine, an angular velocity at a first crank angle at which the engine speed is close to a minimum within one combustion cycle of each cylinder is calculated as a pre-combustion angular velocity, and an angular velocity at a second crank angle at which the engine speed is close to a maximum within the same combustion cycle is calculated as a post-combustion angular velocity. An amount of rotation variation caused between the first and second crank angles is calculated based on the pre-combustion and post-combustion angular velocities of the same combustion cycle, and is compared with a predetermined misfire criterion to determine whether or not misfire has occurred. When misfire is detected, a required operation is performed, for example, a warning lamp is turned on or the fuel supply quantity is increased.

Abstract: To permit easy and adequate setting of a gain in an internal combustion engine (hereinafter be called an “engine”) for the surer stabilization of an idle speed, the present invention provides a device for controlling an air volume during an idle operation of the engine. This device is provided with a first estimation unit for estimating a current output torque correlation value corresponding to a present intake-air volume of the engine; a second estimation unit for estimating an output torque correlation value correction amount corresponding to a difference between a current engine speed and a target engine speed of the engine; a third estimation unit for estimating a target output torque correlation value based on the correlation value and the correction amount; and a control unit for controlling an intake-air-volume adjusting system of the engine to achieve an intake-air volume which is equivalent to the target output torque correlation value.

Abstract: A device for periodically estimating the temperature of an exhaust-gas purifying catalyst provided in the exhaust pipe of an internal combustion engine. The device includes first, second, third, and fourth estimation blocks. The first estimation block estimates the temperature of exhaust gases that are discharged from the combustion chamber, as a steady catalytic temperature under a steady operation of the internal combustion engine, based on operating conditions of the internal combustion engine. The second estimation block estimates a representative temperature of the interior wall of the exhaust pipe extending from the internal combustion engine to the catalyst, based on the estimated steady catalytic temperature. The third estimation block estimates a catalyst inflow exhaust-gas temperature that flows in the catalyst, based on the estimated steady catalytic temperature and the estimated representative temperature.

Abstract: An air-fuel ratio control apparatus for a multiple cylinder engine, having catalytic converters and air-fuel ratio sensors in an exhaust manifold, comprises exhaust air-fuel ratio variation determining means which determines a variation in exhaust air-fuel ratio between one cylinder and other cylinders in one cylinder group when an exhaust air-fuel ratio on one of the rich side and the lean side with respect to a predetermined value is detected as to the one cylinder twice in succession, an exhaust air-fuel ratio on the other one of the rich side and the lean side from the exhaust air-fuel ratio of the one cylinder, and combustion air-fuel ratio control means which feedback-compensates the quantity of fuel injected into the one cylinder, and feedback-compensated the quantity of fuel injected into the other cylinder in a direction opposite to the direction in which the quantity of fuel injected into the one cylinder is compensated.

Abstract: A catalyst deterioration suppressing apparatus and method stops supply of fuel when an engine is decelerating, and prohibits the supply of fuel from being stopped when the catalyst temperature is equal to or higher than a predetermined temperature when the engine is decelerating. When the supply of fuel is prohibted from being stopped, the air-fuel ratio is prohibited from being feedback-controlled. As a result, it is possible to control the air-fuel ratio in a stable manner while suppressing deterioration of a catalyst.

Abstract: There is provided an exhaust emission control apparatus for an internal combustion engine, which comprises a cylinder suspend operation control section that provides control to suspend combustion of suspended cylinders selected from among a plurality of cylinders according to an operating state of the internal combustion engine, a first exhaust passage connected to the suspended cylinders, a second exhaust passage connected to operating cylinders other than the suspended cylinders, a second exhaust purifying catalyst disposed in the second exhaust passage, and a first exhaust purifying catalyst disposed in the first exhaust passage and having a higher capability to purify exhaust gas than the second exhaust purifying catalyst. It is therefore possible to prevent deterioration of exhaust gas even in the case where cylinders are partially suspended.

Abstract: A cooling apparatus of an internal combustion engine includes an insert that is deformable, and a surface of the insert opposing a cylinder bore wall is close to the cylinder bore wall after the insert is inserted into a water jacket. A cooling apparatus of an internal combustion engine includes a cylinder block having a water jacket in which an insert is disposed; the cylinder block is machined so that a water hole or an aperture having a size corresponding to a size of the insert is formed in the cylinder block and the insert can be inserted into the water jacket through the water hole or the aperture.

Abstract: To permit easy and adequate setting of a gain in an internal combustion engine (hereinafter be called an “engine”) for the surer stabilization of an idle speed, the present invention provides a device for controlling an air volume during an idle operation of the engine. This device is provided with a first estimation unit for estimating a current output torque correlation value corresponding to a present intake-air volume of the engine; a second estimation unit for estimating an output torque correlation value correction amount corresponding to a difference between a current engine speed and a target engine speed of the engine; a third estimation unit for estimating a target output torque correlation value based on the correlation value and the correction amount; and a control unit for controlling an intake-air-volume adjusting system of the engine to achieve an intake-air volume which is equivalent to the target output torque correlation value.

Abstract: A cooling apparatus of an internal combustion engine includes a closed deck-type cylinder block and an insert. The cylinder block includes a water jacket and an upper deck including a water hole formed therein. The insert is disposed in the water jacket and inserted into the water jacket through the water hole. The insert is fixed relative to the cylinder block at a water hole portion such that the insert is fixed in position in a flow direction of the cooling water. A stopper for preventing the insert from moving downstream in a flow direction of the cooling water may be formed, and the insert engages the stopper such that the insert is fixed in position in the flow direction of the cooling water.

Abstract: A device for periodically estimating the temperature of an exhaust-gas purifying catalyst provided in the exhaust pipe of an internal combustion engine. The device includes first, second, third, and fourth estimation blocks. The first estimation block estimates the temperature of exhaust gases that are discharged from the combustion chamber, as a steady catalytic temperature under a steady operation of the internal combustion engine, based on operating conditions of the internal combustion engine. The second estimation block estimates a representative temperature of the interior wall of the exhaust pipe extending from the internal combustion engine to the catalyst, based on the estimated steady catalytic temperature. The third estimation block estimates a catalyst inflow exhaust-gas temperature that flows in the catalyst, based on the estimated steady catalytic temperature and the estimated representative temperature.

Abstract: A metal gasket is designed so that mounting and removal from a cylinder block using a bolt is easy regardless of the direction of the attaching surface and there is no risk of moving or drop off. The gasket is made of two laminated metal base plates. At a base plate part near a bolt hole of one metal base plate, a bolt engaging piece projects so that the diameter of the bolt hole is smaller than the diameter of the bolt for fastening, and an assistant piece for handling is integrated thereto. At the base plate part of the other plate overlapping the assistant piece, a cut recess is formed. When inserting the bolt into the bolt hole of the metal gasket, the bolt engaging piece is struck against the bolt and is elastically bent, and allows the bolt to pass. The gasket mounted on the bolt is kept at the mounting position by the pressing action to the bolt from the impact resilience force of the bolt engaging piece.

Abstract: An ignition timing control system for an internal combustion engine includes an electronic control unit. In a transition state where an in-cylinder EGR rate varies, the unit calculates an ignition timing corresponding to the in-cylinder EGR rate by means of linear interpolation based on ignition timings for EGR and non-EGR operations determined from maps, sets a retard amount based on the ratio of the in-cylinder EGR rate to a target EGR rate, and performs ignition timing control based on a corrected ignition timing obtained by subtracting the retard amount from the calculated ignition timing, thus preventing occurrences of knocking due to excessively advanced ignition timing, and deteriorated fuel consumption and drivability.

Abstract: There is provided an exhaust emission control apparatus for an internal combustion engine, which comprises a cylinder suspend operation control section that provides control to suspend combustion of suspended cylinders selected from among a plurality of cylinders according to an operating state of the internal combustion engine, a first exhaust passage connected to the suspended cylinders, a second exhaust passage connected to operating cylinders other than the suspended cylinders, a second exhaust purifying catalyst disposed in the second exhaust passage, and a first exhaust purifying catalyst disposed in the first exhaust passage and having a higher capability to purify exhaust gas than the second exhaust purifying catalyst. It is therefore possible to prevent deterioration of exhaust gas even in the case where cylinders are partially suspended.

Abstract: A metal gasket for sealing a region whereat there exists three pairs of sets of opposing surfaces between a cylinder block, a chain case and a cylinder head of a chain driving engine. The metal gasket includes an elastic seal member provided on an inner rim of a chain opening formed in said metal gasket, and a storing structure for liquid gasket material used for sealing. The storing structure defined is an enlargement of the chain opening oriented to coincide with a juncture of the region whereat three pairs of opposing surface areas exist, the enlargement defining a cavity in which is housed liquid gasket material and a through hole is provided externally of the cavity.