Patent ID: 7421838

Claim:
A regeneration control device that regenerates a filter that traps microscopic particulate matter in the exhaust gas of an engine, comprising: a first temperature sensor that detects the temperature either upstream or downstream from the filter as a first temperature; a second temperature sensor that detects the other temperature as a second temperature; and a microcomputer to: calculate a hypothetical bed temperature of the filter based on the first temperature detected by the first temperature sensor or the second temperature detected by the second temperature sensor; calculate a heat radiation coefficient corresponding to heat radiated from the filter to the external atmosphere according to an exhaust gas flow rate; calculate an estimated temperature of the second temperature based on the first temperature detected by the first temperature sensor and the heat radiation coefficient; calculate an estimated bed temperature of the filter based on the hypothetical bed temperature and based on a difference between the second temperature detected by the second temperature sensor and the second temperature's estimated temperature; and control the engine so as to raise the engine's exhaust gas temperature based on the estimated bed temperature.