Toyota Jidosha Kabushiki Kaisha

Kenichi Tsujimoto

Shinya Hirota

Mikio Inoue

Tomihisa Oda

Takanori Ueda

Kuniaki Niimi

Akinori Morishima

Kuniaki Nimi

Mikio Inque

A control apparatus for an internal combustion engine according to the invention is applied to an internal combustion engine that is equipped with an exhaust gas treatment device that is provided in an exhaust passage, and a burner device that is provided in the exhaust passage upstream of the exhaust gas treatment device so as to raise a temperature of exhaust gas supplied to the exhaust gas treatment device. The control apparatus performs an increase control for increasing a concentration of oxygen in exhaust gas supplied to the burner device if the concentration of oxygen is not higher than a predetermined required concentration of oxygen when there is a request to operate the burner device. The combustion performance of the burner device is stably ensured by securing or compensating for an insufficient concentration of oxygen.

Control apparatus for internal combustion engine

An operation control apparatus for an internal combustion engine includes: an exhaust emission purifier; a fuel supplying valve for supplying fuel to an exhaust passage; ignition means for igniting the fuel supplied; a warm up determining section for determining whether or not the purifier need be warmed; an exhaust heating determining section for determining whether or not the engine is in an operational state in which the fuel should be ignited and burned; an exhaust heating predicting section for predicting the transition from the operational state in which the fuel should not be ignited and burned to an operational state in which the fuel should be ignited and burned; and a heat generation temperature setting section for setting the temperature of a heating portion of the ignition means based on the result by the heating determining section and the predicting section.

Operation control apparatus and method for internal combustion engine

An apparatus that raises temperature of a post-catalyst at an early time while suppressing reducing agent poisoning of the post-catalyst and discharge of a reducing agent into the outside when a pre-catalyst and the post-catalyst are arranged in series in an exhaust passage of an internal combustion engine in order from an upstream side thereof. The pre-catalyst is arranged to allow an exhaust gas to flow between an outer peripheral surface thereof and an inner peripheral surface of the exhaust passage. A reducing agent addition valve adding a reducing agent to allow the reducing agent to pass through the pre-catalyst is arranged immediately upstream of the pre-catalyst in the exhaust passage. Further, a retention catalyst is arranged in the exhaust passage between the pre-catalyst and the post-catalyst, to temporarily retain the reducing agent in the exhaust gas.

Exhaust gas purification apparatus in an internal combustion engine

An exhaust gas control device of an internal combustion engine has an exhaust treatment device that purifies an exhaust gas. The exhaust gas control device is formed such that unburned fuel is supplied into the exhaust gas by a fuel addition valve, and the unburned fuel is ignited by a glow plug, to generate thereby a flame that reaches an upstream end of an exhaust treatment device. The unburned fuel is caused to become adhered to the upstream end of the exhaust treatment device before a generated flame reaches the exhaust treatment device. Then, the unburned fuel adhered to the upstream end of the exhaust treatment device burns by the flame.

Exhaust gas control device of internal combustion engine

An exhaust purification system of an internal combustion engine, having an exhaust purification catalyst in the exhaust passage of the engine of a vehicle, a fuel supply device provided in the exhaust passage upstream the exhaust purification catalyst and supplies fuel to an exhaust gas flowing into the catalyst, a heating device which heats the fuel supplied from the fuel supply device, and a controller which controls the heating device. The controller controls the heating device, when a first processing request based on a state of the exhaust purification catalyst is standing and a second processing request based on an operating state of the vehicle is not standing (t), to a pre-heating temperature lower than an ignition threshold capable of igniting the fuel and, when the first processing request and the second processing request are standing (t), to an ignition temperature higher than the ignition threshold.

Exhaust gas purifying system of an internal combustion engine

A reducing agent addition valve is arranged in a position in which at least part of a reducing agent added to an exhaust gas in an exhaust passage at a location upstream of a precatalyst reaches the precatalyst in the state of liquid, and the reducing agent is supplied in a more suitable state to an exhaust gas purification device which is arranged in the exhaust passage at a downstream side of the precatalyst. When the addition of the reducing agent is performed by the reducing agent addition valve, the flow rate of the exhaust gas flowing into the precatalyst is decreased so that at least part of the reducing agent, which has reached the precatalyst and has vaporized in the precatalyst, is caused to flow back.

Exhaust gas purification system for an internal combustion engine

An exhaust purification system of an internal combustion engine is provided with an exhaust treatment device which purifies exhaust, a fuel feed device which is arranged at an upstream side from the exhaust treatment device and which feeds fuel to the engine exhaust passage, an ignition device which causes fuel which is fed from the fuel feed device to ignite, and a flow regulating device which regulates the flow rate of exhaust gas which flows toward the ignition device. The fuel feed device is formed so as to feed liquid fuel. The system has an operating region in which due to the fuel which is fed to the engine exhaust passage burning, backflow of the exhaust gas occurs. Fuel is made to burn in the operating region. Further control is performed to make the flow rate of the exhaust gas increase during the period from when combustion of fuel should be started to when combustion of the fuel ends.

Exhaust purification system of internal combustion engine

An internal combustion engine in an engine exhaust passage of which an exhaust purification catalyst () having an oxidation function is arranged and in the engine exhaust passage upstream of the exhaust purification catalyst () of which a small-sized oxidation catalyst () and a fuel feed valve () for feeding fuel to the small-sized oxidation catalyst () are arranged. When activating the exhaust purification catalyst (), the fuel fed from the fuel injector () is used to heat the small-sized oxidation catalyst () and when the exhaust purification catalyst () is further raised in temperature, the fuel fed from the fuel feed valve () is increased and reformed fuel is exhausted from the small-sized oxidation catalyst ().

Exhaust purification device of internal combustion engine

A technique is provided which is capable of reducing an amount of smoke generated in a temperature raising system in which fuel added to an exhaust gas flowing through an exhaust passage is caused to combust at the time of requesting a temperature rise in an exhaust gas purification catalyst. When a request for raising the temperature of an exhaust gas purification catalyst is made, bypass control is carried out in which the exhaust gas having bypassed a turbine is caused to flow into the exhaust gas purification catalyst through a bypass passage, and fuel ignition control is carried out in which a fuel addition valve is caused to add fuel to the exhaust gas which has flowed out of the turbine, and a glow plug is caused to ignite the added fuel.

Temperature raising system for an exhaust gas purification catalyst

An object is to provide a technology with which the temperature of exhaust gas can be raised with improved efficiency in cases where a catalyst apparatus including a catalyst having an oxidizing ability is provided in an exhaust passage of an internal combustion engine. According to the present invention, a catalyst apparatusthat is provided in the exhaust passageof the internal combustion engine and to which reducing agent is supplied from upstream when the temperature of the exhaust gas is to be raised is equipped with at least first and second catalystshaving an oxidizing ability. The first catalystis configured in such a way that the exhaust gas flows through a gap between its outer circumferential surface and the inner circumferential surface of the exhaust passage. The second catalystis disposed downstream of the first catalystwith a spacehaving a specific width Ws between it and the first catalyst

Catalyst apparatus and exhaust gas purification system for internal combustion engine

An object of the present invention is to prevent an excessive temperature rise of a precatalyst in the case where the precatalyst is provided in the exhaust passage upstream of an exhaust gas purification apparatus and has a heat capacity smaller than that of the exhaust gas purification apparatus, and reducing agent is added from a reducing agent addition valve toward an upstream end surface of the precatalyst. According to the present invention, the reducing agent addition valve is located in such a way that the reducing agent added through it reaches the precatalyst in a liquid state. In the case where the level of activity of the precatalyst is higher than a specific level at the time when the addition of reducing agent through the reducing agent addition valve is performed so as to supply the reducing agent to the precatalyst and the exhaust gas purification apparatus, the reducing agent is added more intensively than in the case where the level of activity of the precatalyst is not higher than the specific level.

Exhaust gas purification system for internal combustion engine

An exhaust gas control apparatus includes an oxidation catalyst, a compact oxidation catalyst having a smaller cross section than that of an engine exhaust passage, a fuel supply valve, a glow plug, and an electronic control unit. The control modes for the exhaust gas control apparatus include a first control mode where the fuel is supplied from the fuel supply valve, heated by the glow plug, and ignited, a second control mode where the fuel is supplied from the fuel supply valve, and heated by the glow plug but is not ignited, and a third control mode where the fuel is supplied from the fuel supply valve and the glow plug does not provide heating. The electronic control unit selects the first or third control mode in the operation region where ignition is possible, and selects the second or third control mode in the operation region where ignition is not possible.

Exhaust gas control apparatus for internal combustion engine

A degree of dispersion of a reducing agent added to an exhaust gas flowing into an exhaust gas purification apparatus is controlled. Before addition fuel is added, a valve opening Vd of a flow area changing valve is changed to generate pulsation of the exhaust gas, so that addition valve vicinity exhaust gas pressure Pg varies periodically. Addition timing TMad is controlled to synchronize with extremum arrival timing TMe. High or low dispersion type addition control adds fuel at timing (CP) when the addition valve vicinity exhaust gas pressure Pg becomes a maximum value Pgmax, at timing (TP) when at a minimum value Pgmin, or at both timings (CP, TP).

An internal combustion engine wherein an HC treatment catalyst () having the function of adsorbing the HC in the exhaust gas is arranged upstream of the NOx selective reducing catalyst (), an urea aqueous solution fed from the reducing agent feed valve () is arranged upstream of the HC treatment catalyst (), urea, and NOx contained in the exhaust gas, and HC adsorbed on the HC treatment catalystare reacted with each other to form intermediate products having cyano groups, oximes, and amino groups, and these intermediate products are sent to the NOx selective reducing catalyst ().

In an internal combustion engine, a pair of NOstoring catalysts are arranged in series in an engine exhaust passage. When causing the upstream NOstoring catalyst to release NOand store the released NOin the downstream NOstoring catalyst, the oxygen concentration in the exhaust gas is temporarily reduced in a state where the exhaust gas is maintained at a lean air-fuel ratio. As opposed to this, when releasing NOfrom the upstream NOstoring catalyst and the downstream NOstoring catalyst and reducing the NO, the air-fuel ratio of the exhaust gas is temporarily switched from lean to rich.

Growing community of inventors

Susono, Japan

Kenichi Tsujimoto