Regeneration device for exhaust-gas purifying device

A regeneration device for a filter which is provided in an exhaust system of an internal combustion engine, the regeneration device comprising:

• an injector for injecting fuel into a cylinder of the internal combustion engine;
• a glow plug which is energized to be heated to increase a temperature inside the cylinder;
• and
• an electronic control unit (ECU) configured for executing a regenerating operation for restoring a purification capacity of the filter by controlling the injection of fuel of the injector and the energization of the glow plug,
• wherein during the regenerating operation, the ECU controls the injection of fuel of the injector by a multi-stage injection including at least a post injection and energizes the glow plug at a duty ratio to burn, within the cylinder, fuel supplied by the post injection,
• the ECU further configured for detecting an operating state of the internal combustion engine, an energization amount map in which the duty ratio is set so as to increase more as the operating state of the internal combustion engine lowers, wherein the ECU sets the duty ratio at which the glow plug is energized by referring to the energization amount map based on the operating state detected by the ECU;
• and
• a cylinder pressure sensor for detecting a pressure inside the cylinder, the ECU further configured for estimating an actual heat generation rate of the post injection based on a detection value of the cylinder pressure sensor and the ECU further configured for executing a learning correction operation of the duty ratio of the energization amount map based on a difference between the actual heat generation rate estimated by the ECU and a predetermined target heat generation rate.