Patent ID: 7293410

Claim:
An internal combustion engine comprising: a filter in an exhaust path of the internal combustion engine that captures particulates from exhaust in the exhaust path; an inlet air throttle in an intake air path of the internal combustion engine that controls intake air amount; a fuel injection that sprays fuel to supply to the internal combustion engine; and a control unit that determines a regeneration condition when an amount of particulate sediment is greater than a predetermined value, controls the intake air amount and a fuel injection amount with control signals when the regeneration condition is determined, determines when regeneration conditions deviate from prescribed regeneration conditions during regeneration of the filter, estimates a trend of a temperature of the filter for a change in an engine operation mode to a first engine operation or a second engine operation, wherein the first engine operation provides a first air/fuel ratio, and the second engine operation provides a second air/fuel ratio that is richer than the first air/fuel ratio, and, when the regeneration conditions deviate, selects one of the first engine operation and the second engine operation where the temperature of the filter falls further based on the trend.