Toyota Jidosha Kabushiki Kaisha

Kazuya Takaoka

Toru Kidokoro

Hirokazu Nishijima

Taiga Hagimoto

Daisuke Shibata

Makoto Ogiso

Arifumi Matsumoto

Tomoyuki Kogo

Kenji Furui

Hiroshi Sawada

Akifumi Uozumi

Yuki Terui

Takeru Shirasawa

Tsuyoshi Obuchi

Kazumasa Shimode

Yamato Nishijima

A control device for an internal combustion engine includes a filter for collecting PM in an exhaust pipe connected to an engine body, and a PM regeneration function for regenerating the filter for collecting PM. The control device of the internal combustion engine includes a filter differential pressure acquisition unit that acquires a filter differential pressure, a pre-regeneration filter differential pressure acquired by the filter differential pressure acquisition unit prior to regeneration of the filter, a pre-post regeneration differential pressure difference acquisition unit that acquires a pre-regeneration differential pressure difference that is a difference between a post-regeneration filter differential pressure acquired by the filter differential pressure acquisition unit after regeneration of the filter, and a PM generation function determination unit that performs an anomaly determination of PM regeneration function when the acquired pre-regeneration differential pressure difference is equal to or less than a preset threshold.

Control device for internal combustion engine

A fault diagnosis device for a fluid feed system comprises a first acquiring part acquiring values as a fluid pressure and pump rotational speed before fluid injection, a second acquiring part acquiring values as a fluid pressure and pump rotational speed during fluid injection, a pump rotational speed difference calculating part calculating a pump rotational speed difference comprising a difference between a pump rotational speed during fluid injection and a pump rotational speed before fluid injection when the fluid pressure before fluid injection and the fluid pressure during fluid injection match, and an abnormality judging part judging if an abnormality has occurred in a flow rate of fluid injected from an injection device based on the pump rotational speed difference.

Fault diagnosis device for fluid feed system and fault diagnosis method for fluid feed system

In the abnormality diagnosis device which carries out an abnormality diagnosis of the reducing agent adding device by obtaining a diagnostic parameter which is a parameter correlated with an amount of pressure drop in a reducing agent passage in the case where, from a state in which an addition valve has been closed and in which a voltage to be applied to a pump is controlled to a diagnostic voltage so that the pressure in the reducing agent passage becomes a predetermined pressure, the addition valve is made to open in a state where the voltage to be applied to the pump is maintained at the diagnostic voltage, and by making a comparison between the diagnostic parameter and a predetermined threshold value, the abnormality diagnosis is carried out by using the diagnostic parameter or the predetermined threshold value which is corrected based on the pump discharge capacity of the pump.

Abnormality diagnosis device for reducing agent adding device

An object of the disclosure is to provide a technology that enables abnormality diagnosis of an NOx trap catalyst to make the diagnosis that the NOx trap catalyst is abnormal even if the degree of deterioration of the NOx trap catalyst is relatively small yet. When performing abnormality diagnosis of an NOx trap catalyst, a system according to the disclosure performs a lean temperature raising process, which is the process of raising the temperature of the NOx trap catalyst to or above a predetermined temperature while keeping the air-fuel ratio of the exhaust gas flowing into the NOx trap catalyst at a lean air-fuel ratio. The system diagnoses abnormality of the NOx trap catalyst on the basis of the NOx storage efficiency of the NOx trap catalyst or a parameter correlating with that NOx storage efficiency after the completion of the lean temperature raise process.

Abnormality diagnosis system for exhaust gas purification apparatus

There is provided a technology pertaining to abnormality diagnosis of an NSR catalyst that enables the diagnosis that the NSR catalyst is abnormal to be made even when the degree of deterioration of the NSR catalyst is relatively small yet. An abnormality diagnosis apparatus is applied to an exhaust gas purification apparatus having an NSR catalyst and a fuel addition valve. The abnormality diagnosis apparatus includes a controller configured to perform a specific fuel addition process and diagnose the NSR catalyst. The controller starts the specific fuel addition process when the NSR catalyst is in a specific start condition, and diagnoses the NSR catalyst on the basis of the quantity of NOx flowing out of the NSR catalyst over a specific period in the period from when the specific fuel addition process is started to when the temperature of the NSR catalyst reaches the thermal desorption temperature.

Abnormality diagnosis apparatus for exhaust gas purification apparatus

An object is to prevent a wrong diagnosis from being made in an abnormality diagnosis apparatus for an exhaust gas purification system including a filter and a PM sensor. After sensor regeneration is performed, the application of voltage to the PM sensor is started, and thereafter abnormality diagnosis of the PM sensor is performed based on whether or not a signal is output from the PM sensor. Abnormality diagnosis of the filter is performed based on whether or not the output value of the PM sensor reaches a predetermined abnormality criterion value. If the output value of the PM sensor reaches the predetermined abnormality criterion value before a predetermined diagnosis completion time after the abnormality diagnosis of the PM sensor, the filter is diagnosed as abnormal, and the application of voltage to the PM sensor is stopped at that time.

Abnormality diagnosis apparatus for exhaust gas purification system

In a failure diagnosis apparatus that carries out standard diagnosis processing in which a failure of the particulate filter is diagnosed by making a comparison between an output value of the PM sensor at the time when a predetermined period of time has passed from a point in time at which sensor regeneration processing for removing the particulate matter deposited on an insulation layer of the PM sensor has ended, and a predetermined threshold value, the standard diagnosis processing is carried out in the case where rich spike processing according to the in-cylinder rich control is not carried out during the predetermined period of time, whereas the rich spike processing according to the in-cylinder rich control is carried out during the predetermined period of time, the standard diagnosis processing is not carried out.

Failure diagnosis apparatus for an exhaust gas purification system

A function diagnostic system for a filter of an internal combustion engine may be provided. The function diagnostic system may include a PM sensor and an electronic control unit. The electronic control unit may be configured to: calculate a NOx conversion rate in the filter; determine whether a NOx converting function of the filter is normal; execute a sensor regeneration process for removing the PM deposited between an electrodes of the PM sensor; continuously monitor an output value of the PM sensor after a predetermined PM deposition restart time, after execution of the sensor regeneration process is finished; and determine that there is an abnormality in a PM trapping function of the filter, when the output vale of the PM sensor, which has been continuously monitored, is reduced when the electronic control unit determines that the NOx converting function of the filter is in a normal status.

Function diagnostic system for filter of internal combustion engine

Embodiments of the present disclosure may improve the accuracy of abnormality diagnosis of a particulate filter using the output value of a particulate matter (PM) sensor provided in an exhaust passage. A time when deposition of PM between electrodes of the PM sensor is restarted after completion of a sensor recovery process may be specified as a PM deposition restart time. A process of diagnosing an abnormality of a filter based on the output value of the PM sensor at a first determination time after the PM deposition restart time may be specified as a filter diagnosis process. To determine, whether the filter diagnosis process is to be performed, a change rate of the output value of the PM sensor in a time period from the PM deposition restart time to a predetermined second determination time before the first determination time, may be compared with a threshold value.

Abnormality diagnosis apparatus for particulate filter

The invention provides a technique for more accurately executing failure diagnosis for an exhaust gas control apparatus having both a selective reduction function and a filter function. To this end, a failure diagnosis apparatus according to the invention for the exhaust gas control apparatus having both the selective reduction function and the filter function computes a NOpurification rate pertaining to a case where the exhaust gas control apparatus is normal based on an estimated value of the amount of particulate matter (PM) collected or accumulated in the exhaust gas control apparatus and an estimated value of the NOratio of exhaust gas flowing into the exhaust gas control apparatus, and determines that the exhaust gas control apparatus fails when the difference between the result of the calculation and an actual NOpurification rate exceeds a threshold.

Failure diagnosis apparatus for exhaust gas control apparatus

A filter abnormality determination system includes: a PM sensor configured to introduce a part of exhaust gas flowing in the exhaust gas passage on the downstream side of a filter into a sensor body and to correlate a sensor output with an amount of particulate matter accumulated on a sensor element in the sensor body; an abnormality determining unit configured to perform filter abnormality determination on the basis of the output of the PM sensor; a determination timing determining unit configured to determine a timing at which the abnormality determining unit performs the abnormality determination on the basis of an estimated amount of particulate matter accumulated on the sensor element; and a determination performing adjusting unit configured to adjust the performing timing determined by the determination timing determining unit depending on a variation of an exhaust gas flow rate per unit time in the exhaust gas passage in which the PM sensor is disposed.

Filter abnormality determination system

Embodiments of the present disclosure improve the accuracy of abnormality diagnosis of a particulate filter using the output value of a PM sensor provided downstream of the particulate filter in an exhaust passage. A configuration of the invention compares a change rate of an output value of the PM sensor prior to execution of a filter diagnosis process of diagnosing an abnormality of the filter based on the output value of the PM sensor, with a reference value and determines whether a filter abnormality process is to be performed. A higher value is set to the reference value, which is to be compared with the change rate of the output value of the PM sensor, in the case where the deposition amount of PM between electrodes of the PM sensor is expected to be large, compared with the case where the deposition amount of PM is expected to be small.

In a failure diagnosis device of an emission control system that utilizes an electrode-based PM sensor to diagnose a failure of a particulate filter, some embodiments may be to suppress reduction of accuracy of diagnosis of a failure due to in-cylinder rich control. The failure diagnosis device of the emission control system performs a measurement process. The measurement process includes a sensor recovery process of removing PM depositing between the electrodes of the electrode-based PM sensor, a process of starting application of the predetermined voltage to the electrodes of the PM sensor after completion of the sensor recovery process, and a process of obtaining an output value of the PM sensor after elapse of a predetermined time period since the start of application of the predetermined voltage to the electrodes of the PM sensor.

Failure diagnosis device of emission control system

An object of the invention is to suppress a reduction in accuracy of abnormality diagnosis with an abnormality diagnosis device for an exhaust gas control apparatus that performs the abnormality diagnosis regarding the exhaust gas control apparatus by using the amount of NOflowing into an SCR catalyst as a parameter. In the abnormality diagnosis device for an exhaust gas control apparatus according to the invention provided with an exhaust gas control apparatus including the SCR catalyst, a supply device supplying ammonia to the exhaust gas control apparatus, an EGR device allowing some of exhaust gas to flow back to an intake passage from an exhaust passage further downstream than the supply device, acquiring means for acquiring a NOinflow amount as the amount of NOflowing into the exhaust gas control apparatus, and diagnostic means for diagnosing an abnormality of the exhaust gas control apparatus by using the NOinflow amount acquired by the acquiring means as a parameter, the abnormality diagnosis regarding the exhaust gas control apparatus by the diagnostic means is prohibited in a case where the amount of the ammonia allowed to flow back along with the exhaust gas by the EGR device exceeds an upper limit value.

Abnormality diagnosis device for exhaust gas control apparatus

An abnormality diagnosis apparatus includes an exhaust gas purification apparatus arranged in an exhaust passage of an internal combustion engine and including a SCR catalyst; a supply apparatus supplying an additive such as ammonia to the exhaust gas purification apparatus; an EGR apparatus recirculating a part of exhaust gas from the exhaust passage at a downstream side of a position of supplying the additive to an intake passage; obtaining means for obtaining a NOinflow amount into the exhaust gas purification apparatus; diagnosing means for calculating a physical quantity correlated to a NOpurification performance of the exhaust gas purification apparatus using the obtained NOinflow amount, and diagnosing that an abnormality has occurred in the exhaust gas purification apparatus when the physical quantity is smaller than a threshold; and correcting means for, when the additive is recirculated together with a part of the exhaust gas, correcting the threshold to a smaller value than when otherwise.

Growing community of inventors

Susono, Japan

Kazuya Takaoka