Detector for detecting sulfur components
AssigneeToyota Jidosha Kabushiki Kaisha
InventorsHiroshi Otsuki, Hiromasa Nishioka, Katsuhiko Oshikawa, Yoshihisa Tsukamoto, Junichi Matsuo
Life of this patent
Estimating the term…
Abstract
A detector for detecting sulfur components having a storage portion for storing SOX and NOX in the exhaust gas passing through an exhaust passage and a temperature sensor for measuring a temperature of the storage portion. The detector includes a heater for heating the storage portion and determines the current heat capacity (C) of the storage portion on the basis of an increase in (T2−T1) the temperature of the storage portion measured by the temperature sensor and a quantity of heat (QH) generated by the heater when the heater heats the storage portion.
Claims2
A detector for detecting sulfur components comprising a storage portion for storing SOX and NOX in the exhaust gas passing through an exhaust passage, in which the more an amount of stored SOX increases, the more an amount of NOX that can be stored decreases, and which releases only the stored NOX and reduces the released NOX when the air-fuel ratio in the exhaust gas is made stoichiometric or rich, and a temperature sensor for measuring a temperature of said storage portion, measuring an increase in the temperature of said storage portion in the reducing reaction of the released NOX by said temperature sensor, calculating a quantity of heat generated in the reducing reaction of the released NOX on the basis of the measured increase in the temperature and heat capacity of said storage portion so that an amount of released NOX that corresponds to the amount of NOX that can be stored is calculated in order to estimate a current amount of stored SOX, and detecting an integrated amount of SOX passing through said exhaust passage in a given period or a value on the basis of said integrated amount, wherein said detector comprises a heater for heating said storage portion and determines the current heat capacity of said storage portion on the basis of an increase in the temperature of said storage portion measured by said temperature sensor and a quantity of heat generated by said heater when said heater heats said storage portion.
A detector for detecting sulfur components comprising a storage portion for storing SOX and NOX in the exhaust gas passing through an exhaust passage, in which the more an amount of stored SOX increases, the more an amount of NOX that can be stored decreases, and which releases only the stored NOX and reduces the released NOX when the air-fuel ratio in the exhaust gas is made stoichiometric or rich, and a first temperature sensor for measuring a temperature of said storage portion, measuring an increase in the temperature of said storage portion in the reducing reaction of the released NOX by said first temperature sensor, calculating a quantity of heat generated in the reducing reaction of the released NOX on the basis of the measured increase in the temperature and heat capacity of said storage portion so that an amount of released NOX that corresponds to the amount of NOX that can be stored is calculated in order to estimate a current amount of stored SOX, and detecting an integrated amount of SOX passing through said exhaust passage in a given period or a value on the basis of said integrated amount, wherein said detector comprises a second temperature sensor for measuring a temperature in the vicinity of said storage portion and determines a current relationship between the heat capacity of said storage portion and a heat transfer coefficient from said storage portion to the surroundings thereof in order to determine the current heat capacity of said storage portion on the basis of the determined current relationship, because a quantity of heat released from said storage portion from first time to second time while the temperature of said storage portion decreases by releasing heat is represented by on the one hand, the product of an integrated value from said first time to said second time of a temperature difference between the temperature of said storage portion measured by said first temperature sensor and the temperature in the vicinity of said storage portion measured by said second temperature sensor and the heat transfer coefficient, and on the other hand, the product of a decrease in the temperature of said storage portion from said first time to said second time measured by said first temperature sensor and the heat capacity of said storage portion.
Dependencies are inferred from the claim text.