Abstract: An exhaust purifier purifies an exhaust gas of an internal combustion engine used in an exhaust purification system that has an addition unit and a catalyst. The addition unit, disposed in an exhaust pipe of the exhaust purification system, adds an additive agent to the exhaust pipe, and the catalyst, disposed on a downstream side of the addition unit in the exhaust pipe, purifies the exhaust gas with the additive agent added by the addition unit and stored therein. The exhaust purifier determines a total amount of the additive agent to be added, and calculates an exhaust flow velocity of the exhaust gas. The purifier controls the addition unit to enable the additive agent to be added to the exhaust pipe by the total amount determined, such that the purifier controls the addition unit to decrease a per-unit-time addition amount of the additive agent as the exhaust flow velocity decreases.

Abstract: In an addition-amount controller for an exhaust gas purifying agent to be used for an exhaust emission control system, a catalyst has properties of storing NH3 and further decreasing the critical reaction temperature as an amount of NH3 storage at the catalyst is increased. In the addition-amount controller, a present NH3 storage amount that is a storage amount of NH3 of the catalyst is detected at a detection time, the NH3 storage amount of the catalyst is changed by controlling an addition amount by an addition valve, and the NH3 storage amount of the catalyst is controlled to a target NH3 storage amount based on the detected present NH3 storage amount.

Abstract: In an addition-amount controller for an exhaust gas purifying agent to be used for an exhaust emission control system of an engine, one mode is executed based on satisfaction of an execution condition for each mode, from among a plurality of control modes. The control modes includes a purification control mode in which an addition amount of NH3 or an additive serving as a generating source of the NH3 is determined according to a predetermined parameter associated with an amount of NOx in the exhaust gas, and a storage control mode in which the addition amount is set to be larger than that in the purification control mode. When a load on an output shaft of the engine is higher than an allowable level, the execution condition of the storage control mode is determined to be satisfied.

Abstract: An exhaust emission control device reduces nitrogen oxide in exhaust air from an engine. The device includes an exhaust pipe, a catalyst, a supply device, a NOx detecting device, and a control device. The pipe defines a passage for the exhaust air. The catalyst is disposed in the pipe and promotes reduction reaction of the nitrogen oxide. The supply device supplies an additive agent, which is used for the reaction, to an upstream side of the catalyst in the exhaust air flow direction. The detecting device detects the nitrogen oxide included in the exhaust airs which has passed through the catalyst. The control device controls the supply device. The control device determines a deterioration state of the catalyst based on a result detected by the detecting device and reduces an amount of the additive agent, which is supplied, according to the determined deterioration state.

Abstract: An exhaust pipe is provided with a SCR catalyst (NOx catalyst) and an oxidation catalyst. A urea water adding valve and an exhaust gas temperature sensor are provided upstream of the SCR catalyst. A downstream NOx sensor is provided downstream of the SCR catalyst. The oxidation catalyst is provided with a catalyst temperature sensor. An ECU computes a temperature of the oxidation catalyst based on a detection value of the catalyst temperature sensor. Further, the ECU computes a temperature of exhaust gas flowing into the oxidation catalyst based on a detection value of the exhaust gas temperature sensor. The ECU detects ammonia flowing out from the SCR catalyst based on a differential temperature between the temperature of the catalyst and the temperature of the exhaust gas.

Abstract: An additive agent injection valve and a catalyst unit are formed on an exhaust gas tube in an exhaust gas purifying system. The additive agent injection valve injects urea solution into exhaust gas flowing through the exhaust gas passage. The additive agent injection valve has a first spray part having a first traveling distance and a second spray part having a second traveling distance which is longer than the first traveling distance.

Abstract: The exhaust gas purification apparatus includes an additive injection valve for injecting an additive from an injection orifice thereof into an exhaust gas passage through which an exhaust gas flows, and a catalyst disposed downstream of the additive injection valve for promoting an exhaust purification reaction using the additive to purify the exhaust gas. The exhaust gas purification apparatus is configured to inject-supplies, from the additive injection valve, the additive to the exhaust gas by the additive injection valve at upstream of the catalyst, and supply the catalyst with the injected additive together with the exhaust gas utilizing an exhaust flow of the exhaust gas so that the exhaust purification reaction is performed on the catalyst. The additive injection valve is mounted such that the additive is injected from the injection orifice toward an exhaust upstream side with respect to a direction orthogonal to an exhaust gas flow direction.

Abstract: An exhaust pipe is provided with a SCR catalyst (NOx catalyst) and an oxidation catalyst. A urea water adding valve and an exhaust gas temperature sensor are provided upstream of the SCR catalyst. A downstream NOx sensor is provided downstream of the SCR catalyst. The oxidation catalyst is provided with a catalyst temperature sensor. An ECU computes a temperature of the oxidation catalyst based on a detection value of the catalyst temperature sensor. Further, the ECU computes a temperature of exhaust gas flowing into the oxidation catalyst based on a detection value of the exhaust gas temperature sensor. The ECU detects ammonia flowing out from the SCR catalyst based on a differential temperature between the temperature of the catalyst and the temperature of the exhaust gas.

Abstract: An exhaust emission control device includes an exhaust pipe, a catalyst in the pipe promoting reduction reaction of nitrogen oxide in exhaust air, a supply device for supplying an additive agent to an upstream side of the catalyst, a temperature detecting device for detecting exhaust air temperature, and a control device for controlling the supply device to regulate the additive agent amount supplied into the pipe. The control device stops supply of the additive agent when exhaust air temperature is lower than generation temperature needed to generate the reducing agent from the additive agent, and supplies the additive agent when exhaust air temperature is equal to or higher than generation temperature. When a predetermined time has elapsed after a start of supply of the additive agent, the control device reduces the additive agent amount supplied, compared to the additive agent amount supplied before the predetermined time has elapsed.

Abstract: An exhaust emission control device reduces nitrogen oxide in exhaust air from an engine. The device includes an exhaust pipe, a catalyst, a supply device, a NOx detecting device, and a control device. The pipe defines a passage for the exhaust air. The catalyst is disposed in the pipe and promotes reduction reaction of the nitrogen oxide. The supply device supplies an additive agent, which is used for the reaction, to an upstream side of the catalyst in the exhaust air flow direction. The detecting device detects the nitrogen oxide included in the exhaust airs which has passed through the catalyst. The control device controls the supply device. The control device determines a deterioration state of the catalyst based on a result detected by the detecting device and reduces an amount of the additive agent, which is supplied, according to the determined deterioration state.

Abstract: An exhaust emission control device reduces nitrogen oxide included in exhaust air from an internal combustion engine. The device includes an exhaust pipe, a catalyst, a supply device, a tank, and a temperature regulating device. The exhaust pipe defines a passage for exhaust air discharged from the engine. The catalyst is disposed in the exhaust pipe. The catalyst is capable of promoting reduction reaction of the nitrogen oxide in exhaust air. The supply device is for supplying a fluid-state additive agent, which is used for the reduction reaction, to an upstream side of the catalyst in a flow direction of exhaust air. The additive agent is stored in the tank. The temperature regulating device is for regulating temperature of the additive agent, which is supplied by the supply device, to be in a predetermined range.

Abstract: A reducing agent spray control system designed to control an exhaust emission control device such as a urea SCR device for automotive internal combustion engines. The exhaust emission control device includes an injector injecting a spray of a reducing agent into an exhaust pipe of the engine to reduce a selected component such as NOx in exhaust gas to purify the exhaust gas and a pump regulating the pressure of the reducing agent to be sprayed by the injector. The system works to control the pump so as to bring the pressure of the reducing agent to be sprayed by the injector into agreement with a target value, as determined based on the state of the exhaust gas, to ensure the efficiency of purification of the exhaust gas without sacrificing the service life of the pump.

Abstract: An exhaust gas cleaning apparatus for cleaning the exhaust gas from an internal combustion engine includes: an exhaust gas passage through which the exhaust gas flows; a reducing agent injector that injects a reducing agent into the exhaust gas passage; and a reduction catalyst that is provided in the exhaust gas passage downstream of the reducing agent injector to promote, at least, a reduction reaction between a component of the exhaust gas and the reducing agent. The exhaust gas passage includes a bent portion formed with a bend. The reducing agent injector is provided on the outside of the bend of the bent portion to inject the reducing agent in a direction that deviates from a tangent line, which is tangent to a central axis line of the bent portion at a downstream-side end of the bent portion, toward the inside of the bend of the bent portion.

Abstract: In an exhaust gas purifying system having a catalyst provided in an exhaust pipe for carrying out chemical reduction reaction so as to remove NOx contained in exhaust gas from an engine, an additive injection valve is provided in the exhaust pipe at an upstream side of the catalyst for injecting additive agent into the exhaust pipe, so that the chemical reduction reaction at the catalyst is facilitated. An injection port of the additive injection valve is formed into a slit-shape, so that a sheet-like spray is formed when the additive is injected from the additive injection valve.

Abstract: In an addition-amount controller for an exhaust gas purifying agent to be used for an exhaust emission control system of an engine, one mode is executed based on satisfaction of an execution condition for each mode, from among a plurality of control modes. The control modes includes a purification control mode in which an addition amount of NH3 or an additive serving as a generating source of the NH3 is determined according to a predetermined parameter associated with an amount of NOx in the exhaust gas, and a storage control mode in which the addition amount is set to be larger than that in the purification control mode. When a load on an output shaft of the engine is higher than an allowable level, the execution condition of the storage control mode is determined to be satisfied.

Abstract: In an addition-amount controller for an exhaust gas purifying agent to be used for an exhaust emission control system, a catalyst has properties of storing NH3 and further decreasing the critical reaction temperature as an amount of NH3 storage at the catalyst is increased. In the addition-amount controller, a present NH3 storage amount that is a storage amount of NH3 of the catalyst is detected at a detection time, the NH3 storage amount of the catalyst is changed by controlling an addition amount by an addition valve, and the NH3 storage amount of the catalyst is controlled to a target NH3 storage amount based on the detected present NH3 storage amount.

Abstract: In an addition-amount controller for an exhaust gas purifying agent to be used for an exhaust emission control system of an engine, one mode is executed based on satisfaction of an execution condition for each mode, from among a plurality of control modes. The control modes includes a purification control mode in which an addition amount of NH3 or an additive serving as a generating source of the NH3 is determined according to a predetermined parameter associated with an amount of NOx in the exhaust gas, and a storage control mode in which the addition amount is set to be larger than that in the purification control mode. When a rotation speed of an output shaft of the engine is determined to be decelerated from a higher speed state than an allowable level, the execution condition of the storage control mode is satisfied after a predetermined dissatisfaction time period from start of the deceleration.

Abstract: A quantity of a purifying agent that is added into an exhaust gas, reacts with a specific component in the exhaust gas, and purifies the exhaust gas is controlled. A controller is configured so as to be provided with a program to carry out either increment control for increasing the quantity of urea water sequentially or decrement control for decreasing the quantity of the urea water sequentially while monitoring, in NOx in the exhaust gas, the quantity not purified through the reaction with NH3 (the discharged NOx quantity); and switch the quantity control from the currently adopted increment or decrement control to the other increment or decrement control in response to whether the feature of the change of the discharged NOx quantity comes to a predetermined feature.

Abstract: An additive agent injection valve and a catalyst unit are formed on an exhaust gas tube in an exhaust gas purifying system. The additive agent injection valve injects urea solution into exhaust gas flowing through the exhaust gas passage. The additive agent injection valve has a first spray part having a first traveling distance and a second spray part having a second traveling distance which is longer than the first traveling distance.

Abstract: The exhaust gas purification apparatus includes an additive injection valve for injecting an additive from an injection orifice thereof into an exhaust gas passage through which an exhaust gas flows, and a catalyst disposed downstream of the additive injection valve for promoting an exhaust purification reaction using the additive to purify the exhaust gas. The exhaust gas purification apparatus is configured to inject-supplies, from the additive injection valve, the additive to the exhaust gas by the additive injection valve at upstream of the catalyst, and supply the catalyst with the injected additive together with the exhaust gas utilizing an exhaust flow of the exhaust gas so that the exhaust purification reaction is performed on the catalyst. The additive injection valve is mounted such that the additive is injected from the injection orifice toward an exhaust upstream side with respect to a direction orthogonal to an exhaust gas flow direction.