Isuzu Motors Limited

Masafumi Noda

Tadashi Uchiyama

Mitsuhiro Aso

A reactance measurement apparatus has a series circuit has a first circuit including a first resistor and a second circuit including a reactance element, a first voltage generation unit for generating a first AC voltage to apply the same to the series circuit, a second voltage generation unit for generating a second AC voltage having a phase difference with respect to the first AC voltage, a multiplication unit for multiplying the second AC voltage and a second circuit voltage to generate a multiplication voltage, a measurement unit for measuring a voltage of a DC component of the multiplication voltage, a phase shift amount calculation unit for calculating a phase shift amount, and a reactance calculation unit for calculating a reactance of the reactance element based on the phase shift amount.

Reactance measurement apparatus

A particulate matter measuring device includes: a diesel particulate filter (DPF) in which upstream side and downstream side openings of multiple cells partitioned by porous partition walls are alternately plugged; a pair of first electrodes received in a pair of first electrode cells arranged diagonally with a central cell therebetween; a pair of second electrodes received in a pair of second electrode cells arranged diagonally with the central cell therebetween; a first connecting member for connecting the first electrodes to each other; a second connecting member for connecting the second electrodes to each other; and a unit that calculates an amount of particulate matter trapped in the DPF on the basis of capacitance between the electrodes. The four cells which are adjacent to each other around the partition walls of the central cell and sandwiched between the first electrode cells and the second electrode cells are used as measurement cells.

Particulate matter measurement device

An exhaust gas purification device includes a diesel particulate filter (DPF) for capturing particulate matter (PM) in an exhaust gas, a selective catalytic reduction (SCR) device for reducing NOx in the exhaust gas, detecting units for detecting the DPF electrostatic capacity, an estimating unit for estimating the inside temperature of the DPF based on the electrostatic capacity, and a controlling unit for executing forced DPF regeneration. A lower limit temperature is defined as a temperature to trigger PM combustion, and an upper limit temperature is defined as a temperature to avoid filter erosion. The controlling unit executes the forced regeneration with an amount of fuel supplied for causing the inside temperature to reach the lower limit temperature, when the inside temperature is at or above the SCR activation temperature, and executes the forced regeneration with another amount of fuel supplied for causing the inside temperature to reach the upper limit temperature, when the inside temperature is below the SCR activation temperature.

Exhaust purification device for internal combustion engine

An exhaust gas purification device includes a diesel particulate filter (DPF) that collects particulate matter (PM) from an exhaust gas, a urea water spray unit that sprays urea water into the exhaust gas, a selective catalytic reduction (SCR) device that reduces and purifies NOof the exhaust gas, a capacitance detecting unit that detects capacitance of the DPF, a PM accumulation calculating unit that calculates an amount of accumulated PM on the basis of the capacitance, an NOconsumption estimating unit that calculates an amount of consumed NOon the basis of the amount of accumulated PM, and a control unit that controls an engine such that a ratio of NO to NOflowing into the SCR approaches 1:1 on the basis of the estimated consumption.

An exhaust gas purification device for an internal combustion engine, wherein an amount of fuel supply during a forced regeneration is optimized, and a fuel efficiency is effectively improved. The device includes a filter in an exhaust passage of the internal combustion engine for collecting particulate matter in an exhaust gas, an electrostatic capacity detecting unit that detects an electrostatic capacity of the filter, and a filter regenerating unit that supplies fuel to the filter and executes a forced regeneration to burn and remove the particulate matter in the filter. The filter regenerating unit stops supplying fuel when a rate of decrease in the detected electrostatic capacity per predetermined period of time reaches or falls below a predetermined lower threshold, which indicates a drop in burning efficiency of the particulate matter, while the forced regeneration is being executed.

An exhaust gas purification device includes a diesel particulate filter (DPF) that traps particulate matter (PM), an exhaust gas temperature sensor that detects temperature of an exhaust gas, an electrostatic capacity detection unit that detects an electrostatic capacity of the DPF, an accumulated-amount estimation unit that estimates an amount of PM accumulated in the DPF on the basis of the electrostatic capacity, and a filter regeneration unit that can perform forced regeneration. On the basis of an accumulated-amount threshold that is lower than an upper PM accumulation limit, and a temperature threshold at which the accumulated PM can still be burned and removed even if an amount of fuel supply is reduced, the filter regeneration unit performs the forced regeneration if the amount of accumulated PM has reached the accumulated-amount threshold and the exhaust gas temperature reaches the temperature threshold.

A diesel particulate filter ('DPF') including vertically and horizontally stacked cells in which all of vertical and horizontal sides are surrounded by walls formed of a porous material, and sealing end faces of the cells alternately vertically and horizontally are provided with first and second electrodes. In a particulate matter ('PM') sensor in which a PM deposit quantity of the DPF is detected by a capacitance of a capacitor formed by the first and second electrodes, among open cells, the first electrodes are inserted into the open cells arranged in a line in a diagonal direction, and the second electrodes are inserted into the open cells arranged in a line in the diagonal direction and including the open cells secondarily adjacent to each of the open cells into which the first electrodes are inserted.

Growing community of inventors

Kawasaki, Japan

Masafumi Noda