Abstract: An exhaust gas purification system including an exhaust gas purification device having an oxidation catalyst device including an oxidation catalyst and a diesel particulate filter (“DPF”) arranged in order from an upstream side, or a DPF carrying an oxidation catalyst in an exhaust passage of an internal combustion engine. At regeneration of the DPF, when a catalyst temperature index temperature (Tg2), indicating a temperature of the oxidation catalyst, becomes equal to a predetermined determining temperature (Tc1) or above, a temperature of the DPF is raised by supplying an unburned fuel to the upstream side of the oxidation catalyst to thereby oxidize the unburned fuel by the oxidation catalyst. The predetermined determining temperature (Tc1) is changed according to an engine speed Ne of the internal combustion engine.

Abstract: A fuel injection control device that prevents a misfire is provided. The fuel injection control device comprises: target injection amount determination means 3 for determining a target injection amount of each fuel injection, so that the amount of fuel to be supplied to a cylinder in one combustion cycle is supplied in a plurality of fuel injections; and fuel injection correction amount determination means 4 for determining a fuel correction amount of one combustion cycle, wherein the fuel injection correction amount determination means 4 distributes the correction amount among each fuel injection in accordance with the ratio of a target injection amount of each fuel injection in the cylinder.

Abstract: In case of emergency regeneration, i.e. any one of forced regeneration after a judgment is made that purification is insufficient in purification judgment after ending forced regeneration, forced regeneration after time has expired before completing of forced regeneration, or forced regeneration when the pressure difference across a DPF exceeds a predetermined first judging pressure difference under a state where traveling distance of a vehicle is shorter than a predetermined distance for judgment an alarm for urging manual regeneration is issued, and wherein when manual regeneration is designated thereafter manual regeneration is performed and when predetermined conditions are satisfied without the reception of a designation of manual regeneration, automatic regeneration is performed.

Abstract: In a control method of an exhaust emission purification system (1) and the exhaust emission purification system (1), an exhaust throttle valve (14) is opened if an engine load reaches at least a predetermined first judgment value during execution of forced regeneration control with said exhaust throttle valve (14) closed when a vehicle is stopping. If the engine load thereby increases during execution of forced regeneration of a DPF (12) for purifying PM (particulate matter) in exhaust gas with the exhaust throttle valve (14) closed when the vehicle is stopping, a good combustion state can be sustained in a cylinder by opening the exhaust throttle valve (14) and taking fresh air into the cylinder of an engine (10).

Abstract: In an exhaust emission purification method and an exhaust emission purification system where forced regeneration start timing of a DPF for purifying the PM (particulate matters) in exhaust gas is judged based on the comparison of a differential pressure across the DPF with a predetermined differential pressure threshold across the DPF, a differential pressure threshold (?Ps) across the DPF is set by multiplying a reference differential pressure threshold (?Ps0) across the DPF by a coefficient (?(?M)) which varies stepwise or continuously depending on the mileage (?M) of a vehicle after previous forced regeneration. Consequently, the PM can be removed by burning while the amount of PM accumulated unevenly in the DPF is still small, and excessive temperature rise in the DPF resulting from excessive accumulation of PM during forced regeneration and melting-loss of DPF due to excessive temperature rise can be prevented.

Abstract: An exhaust emission purification system including a controller performing exhaust temperature rise control executing multistage delay injection control for raising the exhaust temperature, if the exhaust gas temperature is lower than a predetermined judgment temperature, and performing particulate matter combustion removal control executing post injection control, if the exhaust gas temperature becomes equal to or higher than the predetermined judgment temperature, when forced regeneration of a diesel particulate filter is carried out. Multistage delay injection control is forbidden when an idle operation state of an internal combustion engine is sustained for a predetermined judgment time and a power take-off is in operating state. The diesel particulate filter is thereby kept in a good state in a vehicle equipped for purifying particulate matter in exhaust gas by executing forced regeneration while avoiding variation in engine speed.

Abstract: In regeneration control in a manual regeneration mode, when a first exhaust gas temperature (Tg1) of an exhaust gas flowing into an oxidation catalyst device (12a) is higher than a predetermined determining temperature (Tc1) and an exhaust gas temperature (Tg2) flowing into a DPF device (12b) is higher than a predetermined determining temperature (Tc2) and when an intake temperature (Ta) becomes higher than a predetermined third determining temperature (Tc3), second exhaust gas temperature control carrying out post injection in addition to multi injection is stopped and switched to third exhaust gas temperature rise control carrying out the post injection in addition to normal injection. Thus, in the regeneration control in the manual regeneration mode of a continuous regeneration type DPF device (12) of an engine(10), temperature rise of an engine cooling water can be restricted without stopping an air conditioner, and possible overheat of the engine (10) can be prevented.

Abstract: In an exhaust gas temperature raising control for recovering purification ability of an exhaust gas purification device (12) of an internal combustion engine, the exhaust gas temperature is efficiently raised to a target level with white smoke prevented from being produced.

Abstract: Even in the case of driving for a long time in the low rotation speed driving condition in which the exhaust flow rate is small and an estimation of the PM accumulated amount due to the pressure difference between the front and the back sides of a filter is difficult, the forced regeneration time can be accurately judged, the deterioration of fuel efficiency that is caused by excessive PM trapping can be avoided, and at the same time, thermal runaway that is generated by the excessive accumulated amount of PM and melting damage of the DPF due to this thermal runaway can be prevented.

Abstract: In forced regeneration control of an exhaust gas purification device 12, the number of data for injection control such as the number of meshes of a data map and the number of data maps for multi injection control is decreased while occurrence of torque shock, which is a rapid fluctuation of a generated torque, is avoided.

Abstract: In forced regeneration control of an exhaust gas purification device 12, data for control such as the number of meshes of a data map and the number of data maps for forced regeneration control is reduced and occurrence of torque shock is avoided by smoothly changing a fuel pressure. In the forced regeneration control of the exhaust gas purification device 12, when an operation state of an internal combustion engine 10 is a high-load operation state, normal injection control by stopping multi injection is carried out and according to a rotation speed Ne and a load Q of the internal combustion engine 10, a region for control is divided into a multi-injection control region Rm, a transition region Rt, and a normal injection control region Rn, and in the transition region Rt, data Pt for fuel pressure control obtained by interpolation of data Pml for fuel pressure control on the multi-injection control region Rm side and data Pnl for fuel pressure control on the normal injection control region Rn side is used.

Abstract: In an exhaust gas purification system (1) for conducting control of raising temperature of a DPF (12b) by supplying an unburned fuel to an upstream side of an oxidation catalyst to oxidize it, a minimum value (Qumin) of a first upper limit value (Qu1) acquired by subtracting a fuel injection amount (Qe) for in-cylinder combustion from a first combustible fuel amount (Qa1) limited by an air/fuel ratio, a second upper limit value (Qu2) acquired by subtracting the fuel injection amount (Qe) for in-cylinder combustion from a second combustible fuel amount (Qa2) limited by an atmospheric pressure, and a third upper limit value (Qu3), which is a third combustible fuel amount (Qa3) which can be oxidized by the oxidation catalyst limited by a catalyst temperature index temperature (Tg1, Tg2) and an engine speed (Ne) is set as an upper limit value (Qu) for the unburned fuel supply amount (Qp).

Abstract: A fuel injection control device that prevents a misfire is provided. The fuel injection control device comprises: target injection amount determination means 3 for determining a target injection amount of each fuel injection, so that the amount of fuel to be supplied to a cylinder in one combustion cycle is supplied in a plurality of fuel injections; and fuel injection correction amount determination means 4 for determining a fuel correction amount of one combustion cycle, wherein the fuel injection correction amount determination means 4 distributes the correction amount among each fuel injection in accordance with the ratio of a target injection amount of each fuel injection in the cylinder.

Abstract: An exhaust gas purification system has an exhaust gas purification device (12) for purifying components in exhaust gas from an internal combustion engine (10) such as a diesel engine. In order to recover the purification ability of the exhaust gas purification device (12), and in order to prevent oil dilution occurring when post injection is conducted as part of an in-cylinder fuel injection control during an exhaust gas temperature raising control that raises the temperature of exhaust gas, the system performs the following. In a regenerative control for recovering purification ability of the exhaust gas purification device (12), injection quantities (Qp) of post injections are calculated based on previously set map data (Mp), accumulated to calculate a post injection accumulated injection amount (?Qp), and, when the accumulated injection amount (?Qp) exceeds a predetermined determination value (Cp), the post injection is stopped to cease the regenerative control.

Abstract: A method (1) of controlling an exhaust gas purification system has a DPF device (12), where a regeneration control means (35C) has a forced regeneration mode and an arbitrary regeneration mode. In the forced regeneration mode, when it is determined by a regeneration time determination means (34C) that it is time to regenerate a filter (12b) and the temperature of exhaust gas is low, the exhaust gas temperature is raised by an exhaust gas temperature raising means (351C) to forcibly regenerate the filter (12b). In the arbitrary regeneration mode, the filter is arbitrary regenerated based on the result of detection by a collection amount detection means (32C). While the temperature of exhaust gas is raised in the arbitrary regeneration mode by the exhaust gas temperature raising means (351C), operation of a compressor (41) of a vehicle air conditioner is stopped.

Abstract: In an exhaust gas purification system (1) comprising an exhaust gas purification device (12) having an oxidation catalyst device (12a) carrying an oxidation catalyst and a DPF (12b) arranged in order from an upstream side or a DPF carrying an oxidation catalyst in an exhaust passage (11) of an internal combustion engine (10), in which at regeneration of the DPF (12b), when a catalyst temperature index temperature (Tg2) indicating a temperature of the oxidation catalyst becomes equal to a predetermined determining temperature (Tc1) or above, control of raising a temperature of the DPF (12b) is conducted by supplying an unburned fuel to the upstream side of the oxidation catalyst to thereby oxidize the unburned fuel by the oxidation catalyst, wherein the predetermined determining temperature (Tc1) is changed according to an engine speed Ne of the internal combustion engine (10).

Abstract: In regeneration control, when the catalyst temperature index temperature (Tg2) using the temperature of the oxidation catalyst (12a) as an index is below a predetermined first determination temperature (Tc1), the engine speed of idling is brought to a predetermined first target engine speed (Nei1) which is higher than the engine speed of idling (Nei0) in the ordinary operation, and, further, multi-injection is carried out. On the other hand, when the catalyst temperature index temperature (Tg2) is the predetermined first determination temperature (Tc1) or above, the engine speed of idling is brought to a predetermined second target engine speed (Nei2), which is lower than the predetermined first target engine speed (Nei1) and is higher than the engine speed of idling (Nei0) in ordinary operation, and, further, post injection is carried out, followed by raising of the temperature of an exhaust gas flown into a DPF apparatus (12b) to a predetermined second determination temperature (Tc2).

Abstract: At regeneration control while a vehicle mounting an internal combustion engine (10) is parked, both an exhaust throttle valve (13) and an exhaust brake valve (18) are used and if a catalyst temperature index temperature (Tg2) is lower than a predetermined first determining temperature (Tc1), first exhaust gas temperature rise control is conducted that the exhaust brake valve (18) is set to a fully closed side and multiple injection is carried out in in-cylinder fuel injection control, while if a catalyst temperature index temperature (Tg2) is equal to the predetermined first determining temperature (Tc1) or above, second exhaust gas temperature rise control is conducted that the exhaust brake valve (18) is set to an open side, the exhaust throttle valve (13) is set to the fully closed side, and post injection is carried out in the in-cylinder fuel injection control.

Abstract: In in-cylinder fuel multi-injection conducted during forced regeneration of a DPF (12b), control maps for multi-injection are constructed so as to be different for a first gas temperature raising control, which raises a catalyst temperature index temperature (Tg2, Tg1) to a first judgment temperature (Tc1) only by multi-injection, and for a subsequent second exhaust gas temperature raising control, wherein post-injection is conducted in addition to multi-injection to raise a filter temperature index temperature (Tg2) to a second judgment temperature (Tc2). In so doing, exhaust gas flowing into the DPF (12b) can be rapidly raised in temperature when performing forced regeneration of the DPF (12b), thereby shortening the forced regeneration time and improving fuel consumption for forced regeneration.

Abstract: An exhaust emission control system [1] comprising a continuous regenerating DPF [13] and a DPF controlling means [30C], wherein control is so performed as to accept the operation of a forced regenerating means [34C] at an operation request by a driver when it is judged a traveling distance [?Mc] after starting collection detected by a traveling distance detecting means [33C] has reached a specified judging traveling distance [?M1] even when the DPF controlling means [30C] detects a collection amount [?Pm] detected by a collection amount detecting means [32C] is smaller than a specified judging collection amount [?P1]. Accordingly, in a continuous regenerating DPF [13] capable of manual regenerating, the number of warning such as a blinking regeneration button prompting a manual regeneration is reduced to relieve a driver of trouble.