Abstract: A NOx generation amount control device includes: a cumulative amount calculating part calculating a cumulative NOx amount obtained by adding together a plurality of NOx exhaust amounts calculated for each prescribed time interval; a specifying part specifying a target value of the cumulative NOx amount associated with a movement distance of a moving body or an output value of an engine; an estimating part estimating a predicted NOx amount indicating a predicted cumulative NOx amount based on a rotation speed of the engine and a fuel injection amount; a judging part judging whether the sum of the predicted NOx amount and the cumulative NOx amount exceeds the target value; and a determining part determining a scheduled NOx exhaust amount and determining at least one of an opening degree of the EGR valve and an opening degree of a turbocharger.

Abstract: A selective catalytic reduction (SCR) system that can prevent fixation of urea solution to an interior of a dosing valve when the urea solution is not injected through the dosing valve. An SCR system closes a dosing valve when the exhaust gas temperature is lower than a temperature at which an SCR catalyst becomes active and is provided with a fixation prevention system that opens the dosing valve and controls a supply module to feed the urea solution in the dosing valve back to a urea tank to prevent fixation of the urea solution to the interior of the dosing valve, when the exhaust gas temperature is equal to or higher than a temperature at which the urea solution crystallizes and lower than the temperature at which the SCR catalyst becomes active.

Abstract: An exhaust gas purification system includes a dosing control unit that controls a supply module to supply urea water between a dosing valve and a urea tank in order to remove urea water accumulated in the dosing valve, when receiving a diesel particulate filter regeneration authorization request from an engine control unit, and then transmits the authorization to the engine control unit, when determining that an NH3 amount of a selective reduction catalyst is less than or equal to a prescribed value.

Abstract: An exhaust gas purification device includes an exhaust gas after-treatment device provided in an exhaust passage of an internal combustion engine, and has an oxidation catalyst and a DPF or diesel particulate filter. The exhaust gas purification device also includes an exhaust pipe injector which feeds a fuel to the oxidation catalyst, and a control unit which controls regeneration of the filter by supplying the oxidation catalyst with the fuel from the exhaust pipe injector. The control unit determines whether the filter is in a regeneration-possible state, i.e., whether the oxidation catalyst is maintained at a high temperature allowing regeneration of the filter. If the control unit determines during regeneration control of the filter that the filter is not in the regeneration-possible state, then the control unit halts the regeneration control until the regeneration-possible state is reached.

Abstract: An exhaust gas purification catalyst, using a reducing agent, is provided on an inside of an exhaust pipe via a support member. A baffle portion for preventing the reducing agent from penetrating the exhaust gas purification catalyst is provided on a portion of an internal surface of the exhaust pipe, which is upstream of the exhaust gas purification catalyst.

Abstract: A recovery control system that allows a dosing valve to recover from a malfunction to a normal state, or a liquid feed line through which urea solution is fed to recover from clogging to a normal state. An abnormality detector detects an abnormality of the dosing valve and a recovery controller controls a supply module to feed urea solution in the dosing valve back to an urea tank when the abnormality detector detects the abnormality.

Abstract: A Selective Catalytic Reduction (“SCR”) system that can detect a NOx concentration accurately irrespective of an operation state of an engine is provided. The SCR system including: an SCR device; a dosing valve; a NOx sensor; and an urea solution injection control unit.

Abstract: An exhaust pipe injection control device for controlling an appropriate fuel injection amount regardless of engine rotation speed. The exhaust pipe injection control device includes: a target injection amount setting unit which sets, according to an engine rotation speed and an exhaust gas flow rate, a target injection amount that is injected in a single injection from an exhaust pipe injector; a base pulse width (“BPW”) map in which a fuel injection time of the exhaust pipe injector is set so that, with respect to the target injection amount and an exhaust pipe injection fuel pressure, fuel in the target injection amount is injected; and an exhaust pipe injection executing unit which performs injection from the exhaust pipe injector by referring to the BPW map based on the target injection amount and the exhaust pipe injection fuel pressure.

Abstract: An exhaust gas purification device includes an exhaust gas after-treatment device provided in an exhaust passage of an internal combustion engine, and has an oxidation catalyst and a DPF or diesel particulate filter. The exhaust gas purification device also includes an exhaust pipe injector which feeds a fuel to the oxidation catalyst, and a control unit which controls regeneration of the filter by supplying the oxidation catalyst with the fuel from the exhaust pipe injector. The control unit determines whether the filter is in a regeneration-possible state, i.e., whether the oxidation catalyst is maintained at a high temperature allowing regeneration of the filter. If the control unit determines during regeneration control of the filter that the filter is not in the regeneration-possible state, then the control unit halts the regeneration control until the regeneration-possible state is reached.

Abstract: Forced regeneration start timing of a diesel particulate filter for purifying particulate matter in exhaust gas is judged based on a comparison of a differential pressure across the diesel particulate filter with a predetermined differential pressure threshold across the filter. The predetermined differential pressure threshold is set by multiplying a reference differential pressure threshold by a coefficient which varies stepwise or continuously depending on a mileage of a vehicle after previous forced regeneration. Consequently, particulate matter can be removed by burning while the amount of particulate matter accumulated unevenly in the filter is still small, and excessive temperature rise in the filter resulting from excessive accumulation of particulate matter during forced regeneration and melting-loss of the filter due to excessive temperature rise can be prevented.

Abstract: In in-cylinder fuel multi-injection conducted during forced regeneration of a diesel particulate filter (“DPF”), 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 to a first judgment temperature 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 to a second judgment temperature. In so doing, exhaust gas flowing into the DPF can be rapidly raised in temperature when performing forced regeneration of the DPF, thereby shortening the forced regeneration time and improving fuel consumption for forced regeneration.

Abstract: When an internal combustion engine is in a low rotation speed driving condition, a duration of the low rotation speed driving condition is measured, and when this duration exceeds a predetermined time, the forced regeneration control is performed. Thus, even when an exhaust flow rate is small and an estimation of a particulate matter accumulated amount due to a pressure difference between front and back sides of a filter is difficult, a forced regeneration time can be accurately judged, the deterioration of fuel efficiency that is caused by excessive trapped particulate matter can be avoided, and thermal runaway that is caused by the excessive particulate matter, and the melting damage of the diesel particulate filter due to this thermal runaway, can be prevented.

Abstract: A recovery control system that allows a dosing valve to recover from a malfunction to a normal state, or a liquid feed line through which urea solution is fed to recover from clogging to a normal state. An abnormality detector detects an abnormality of the dosing valve and a recovery controller controls a supply module to feed urea solution in the dosing valve back to an urea tank when the abnormality detector detects the abnormality.

Abstract: An exhaust pipe injection control device for controlling an appropriate fuel injection amount regardless of engine rotation speed. The exhaust pipe injection control device includes: a target injection amount setting unit which sets, according to an engine rotation speed and an exhaust gas flow rate, a target injection amount that is injected in a single injection from an exhaust pipe injector; a base pulse width (“BPW”) map in which a fuel injection time of the exhaust pipe injector is set so that, with respect to the target injection amount and an exhaust pipe injection fuel pressure, fuel in the target injection amount is injected; and an exhaust pipe injection executing unit which performs injection from the exhaust pipe injector by referring to the BPW map based on the target injection amount and the exhaust pipe injection fuel pressure.

Abstract: A selective catalytic reduction (SCR) system that can prevent fixation of urea solution to an interior of a dosing valve when the urea solution is not injected through the dosing valve. An SCR system closes a dosing valve when the exhaust gas temperature is lower than a temperature at which an SCR catalyst becomes active and is provided with a fixation prevention system that opens the dosing valve and controls a supply module to feed the urea solution in the dosing valve back to a urea tank to prevent fixation of the urea solution to the interior of the dosing valve, when the exhaust gas temperature is equal to or higher than a temperature at which the urea solution crystallizes and lower than the temperature at which the SCR catalyst becomes active.

Abstract: An SCR system that can detect a NOx concentration accurately irrespective of an operation state of an engine is provided. The SCR system including: an SCR device 103 provided in an exhaust pipe 102 for an engine E; a dosing valve 104 that injects urea solution on an upstream side of the SCR device 103; a NOx sensor 110 provided in the exhaust pipe 102; and an urea solution injection control unit 127 that controls a urea solution injection quantity according to a NOx concentration value detected by the NOx sensor 110 includes a pressure estimation unit 131 that estimates a NOx sensor pressure that is a pressure inside the exhaust pipe 102 at a position where the NOx sensor 110 is provided, and a NOx concentration detection value correction unit 136 that corrects the NOx concentration value detected by the NOx sensor 110, according to the NOx sensor pressure estimated by the pressure estimation unit 131.

Abstract: Provided is an exhaust gas purification system that can prevent adhesion of urea water in a dosing valve during DPF regeneration. An exhaust gas purification system 100 includes a DCU 126 that controls a supply module 106 to inject or return urea water inside a dosing valve 104 to a urea tank 105 in order to remove urea water accumulated in the dosing valve 104 when receiving a DPF regeneration authorization request from an ECM 125, and then transmits a DPF regeneration authorization to the ECM 125 when determining that an NH3 amount of an SCR catalyst is less than or equal to a prescribed value.

Abstract: The present invention relates to an exhaust pipe, which prevents a reducing agent from penetrating a support member for an exhaust purification catalyst, and effectively prevents the exhaust purification catalyst from being damaged due to the expansion of the support member. An exhaust gas purification catalyst 30 for reducing and purifying nitrogenous compounds contained in exhaust gas discharged from an internal combustion engine, using a reducing agent, is provided on the inside of the exhaust pipe 10 via support member 20. A baffle portion 15 for preventing the reducing agent from penetrating the exhaust gas purification catalyst 30 is provided on the portion of the internal surface of the exhaust pipe 10, which is upstream side of the exhaust gas purification catalyst 30.

Abstract: In emergency regeneration, i.e., after a judgment is made that purification is insufficient after ending forced regeneration, forced regeneration has expired before completion, or when a pressure difference across a diesel particulate filter exceeds a predetermined first judging pressure difference when traveling distance of a vehicle is shorter than a predetermined distance, an alarm for urging manual regeneration is issued. When manual regeneration is designated thereafter by the vehicle's user, manual regeneration is performed. When predetermined conditions are satisfied before receiving a designation of manual regeneration, automatic regeneration is performed.

Abstract: An exhaust emission purification system and a related method of control, wherein an exhaust throttle valve is opened if an engine load reaches at least a predetermined first judgment value during execution of forced regeneration control, and generating an alarm of failure of the exhaust throttle valve if the engine load reaches at least a second judgment value which is larger than the predetermined first judgment value.