Particulate matter detection device

Abstract

A particulate matter detection device (1) includes particle amount detection means (2), temperature detection means (3) for detecting the temperature of exhaust gas, a control unit (4), and a heating means (24). The particle amount detection mechanism (2) includes a particulate matter accumulation unit for accumulating a part of the particulate matter contained in the exhaust gas discharged from the internal combustion engine (5), and a pair of opposing electrodes arranged separately from each other on the particulate matter accumulation unit. . The control unit (4) judges the accumulation amount of the particulate matter in the particulate matter accumulation part based on the electric signal output by the particle amount detection means (2), and receives the exhaust gas detected by the temperature detection means (3). temperature information. The control unit (4) controls the heating mechanism (24) so ​​as to heat the particulate matter accumulation part to 300°C to 800°C when the internal combustion engine (5) is cold started.

Description

technical field [0001] The present invention relates to a particulate matter detection device for detecting the amount of particulate matter contained in exhaust gas generated by an internal combustion engine. Background technique [0002] An exhaust purification device that traps particulate matter (Particulate Matter: PM) contained in exhaust gas is installed on an exhaust pipe of an internal combustion engine. This exhaust purification device includes a particulate matter detection device having a PM sensor that detects the amount of particulate matter contained in exhaust gas, and detects a failure of the exhaust purification device based on information obtained by the particulate matter detection device. [0003] The PM sensor used in the particulate matter detection device is configured in such a way that the PM sensor is heated after the detection of the particulate matter is completed and the next detection is performed, so that the particles adhering to the PM senso...

AI Technical Summary

Problems solved by technology

If the timing of the adhesion of the condensed water overlaps with the timing of heating the above-mentioned PM sensor, it may become the main cause of water-receiving cracking of the PM sensor.

Therefore, in the particulate matter detection device of Patent Document 1, heating for burning and removing the particulate matter in the PM sensor is not performed for a predetermined period of time when the internal combustion engine is cold started.

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