Regeneration control device for exhaust purification device

Patent metadata

Field	Value
Publication number	US-10851694-B2
Application number	US-201716349025-A
Country	US
Kind code	B2
Filing date	Nov 6, 2017
Priority date	Nov 14, 2016
Publication date	Dec 1, 2020
Grant date	Dec 1, 2020

Abstract

A regeneration control device for an exhaust purification device includes a regeneration controller that executes regeneration control in which particulate matters trapped by a filter are removed by combustion, and a post-injection controller that during the regeneration control, executes control in which a time period of a post-injection of fuel executed subsequently to a main injection of fuel is advanced such that a supercharging pressure of a turbosupercharger becomes higher than a supercharging pressure during steady operation.

First claim

The invention claimed is:

1. A regeneration control device for an exhaust purification device in an engine with a turbo-supercharger having the exhaust purification device equipped with a filter that traps particulate matters in exhaust gas discharged from the engine, the regeneration control device for the exhaust purification device comprising:
a regeneration controller that executes regeneration control in which particulate matters trapped by the filter are removed by combustion;
a post-injection controller that during the regeneration control, executes control in which a post-injection time period of fuel executed subsequently to a main injection time period of fuel is advanced such that a supercharging pressure of the turbo-supercharger becomes higher than a supercharging pressure during steady operation; and
an excessive temperature rise determinator that determines a possibility or an impossibility of an excessive temperature rise of the filter in the regeneration control via an exhaust temperature detector, wherein
the post-injection controller executes a control for advancing the post-injection time period only when the excessive temperature rise of the filter in the regeneration control is determined via the excessive temperature rise determinator.

2. The regeneration control device for the exhaust purification device according to claim 1 , further comprising a supercharging pressure detector that detects a supercharging pressure of intake air of the engine, wherein
the post-injection controller advances the post-injection time period of fuel such that the supercharging pressure, detected by the supercharging pressure detector, becomes a target supercharging pressure set in advance.

3. The regeneration control device for the exhaust purification device according to claim 2 , wherein
the post-injection is a plural-stage post-injection including a preceding post-injection and one of a plurality of succeeding post-injections conducted after the preceding post-injection, and
the post-injection controller advances a time period of at least the preceding post-injection to a time period at which the supercharging pressure, having been detected, does not reach the target supercharging pressure, and further advances timing of the one of the plurality of the succeeding post-injections.

4. The regeneration control device for the exhaust purification device according to claim 2 , wherein the post-injection controller increases an injection amount of the post-injection when the supercharging pressure, having been detected during the post-injection time period being advanced to an upper limit value set in advance, does not reach the target supercharging pressure.

5. The regeneration control device for the exhaust purification device according to claim 4 , wherein
the post-injection is a plural-stage post-injection including a preceding post-injection and one of a plurality of succeeding post-injections conducted after the preceding post-injection, and
the post-injection controller increases only an injection amount of the one of the plurality of the succeeding post-injections.

6. The regeneration control device for the exhaust purification device according to claim 1 , further comprising:
an exhaust flow rate detector that detects a flow rate of the exhaust gas, wherein
the excessive temperature rise determinator predicts a temperature rise rate in the filter based on an exhaust temperature detected by the exhaust temperature detector, and determines that the filter has the possibility of having the excessive temperature rise when:
a predictive value of the temperature rise rate is equal to or greater than a threshold value; and
a flow rate of an exhaust gas detected by the exhaust flow rate detector is equal to or less than a threshold value.

7. The regeneration control device for the exhaust purification device according to claim 6 , wherein
the exhaust purification device further includes an oxidation catalyst upstream of the filter in an exhaust flow direction, and
the post-injection is a fuel injection conducted as the regeneration control in a time period not directly contributing to an engine output after the main injection.

8. The regeneration control device for the exhaust purification device according to claim 1 , wherein
the exhaust purification device further includes an oxidation catalyst upstream of the filter in an exhaust flow direction, and
the post-injection is a fuel injection conducted as the regeneration control in a time period not directly contributing to an engine output after the main injection.

Assignees

• Mazda Motor

Inventors

• Mimura Yuki
• Ujihara Kenko
• Morinaga Shinichi

Classifications

• F02D41/1445

  the characteristics being related to the exhaust flow · CPC title

• F01N2900/1602

  Temperature of exhaust gas apparatus · CPC title

• F02D43/00

  Conjoint electrical control of two or more functions, e.g. ignition, fuel-air mixture, recirculation, supercharging or exhaust-gas treatment · CPC title

• F02D41/0245

  by increasing temperature of the exhaust gas leaving the engine · CPC title

• F02D41/0007

  for control of turbo-charged or super-charged engines (control of the pumps per se F02B37/12) · CPC title