Ngk Spark Plug Company, Limited

Yuji Kimoto

Toshiya Matsuoka

Yasuhiro Ishiguro

Katsunori Yazawa

Shingo Ito

Yuko Iwasaki

A sensor control device including an anomaly diagnosis section. When at least one of a first NOconcentration IpW based on the output OPof a first differential amplification circuit () and a second NOconcentration IpN based on the output OPof a second differential amplification circuit () falls within an anomaly diagnosis range ZN, the difference D between IpW and IpN is obtained, and the difference D is stored in a difference accumulation buffer BF such that 16 values of the difference D continuously sampled up to the present are stored. The integrated value (difference integral value) Dint of the difference D is obtained. When the difference integrated value Dint becomes equal to or greater than a predetermined value Di, the sensor control device indicates a diagnosis result of 'anomalous.'

Sensor control device and sensor control method

There is provided a controller for controlling a vehicle device, which includes a circuit board having mounted thereon a control circuit that controls operations of the vehicle device, a first temperature sensor mounted on a first specific region of the circuit board to output a first signal responsive to a temperature of the first specific region of the circuit board and a second temperature sensor mounted on a second specific region of the circuit board to output a second signal responsive to a temperature of the second specific region of the circuit board. The control circuit has an anomaly detection portion that judges the occurrence or non-occurrence of an output anomaly in the first temperature sensor based on the first and second signals of the first and second temperature sensors.

Vehicle device controller and temperature sensor anomaly detection method therefor

In an oxygen sensor control apparatus, after start of fuel cut, the weighted average Ipd of corrected values obtained by multiplying the output value of a mounted oxygen sensor by a correction coefficient Kp is obtained as a representative value Ipe, representing the corrected values in the fuel cut period (S). In the case where the number of times the representative value Ipe is continuously judged not to fall outside a second range (S: NO) and to fall outside a first range (S: YES) reaches 10 (a first number of times) (S: YES), a new correction coefficient Kp is computed (S). In the case where the number of times the representative value Ipe is continuously judged to fall outside the second range (S: YES) reaches 4 (a second number of times smaller than the first number of times) (S: YES), a new correction coefficient Kp is computed (S).

Oxygen sensor control apparatus

It is an object of the invention to provide a gas detecting device capable of relieving the influence of an environment such as a temperature, a humidity or a wind velocity to detect a change in a concentration of a specific gas and an autoventilation system for a vehicle using the gas detecting device. More specifically, a gas detecting device () using a gas sensor element () changing a sensor resistance Rs depending on a concentration of a gas such as NOx and an autoventilation system () for a vehicle according to the invention A/D convert the output of a sensor resistance value converting circuit () to acquire a sensor output value S(n), calculates a base value B(n) based on B(n)=B(n&#x2212;1)+k{S(n)&#x2212;B(n&#x2212;1)}, and furthermore, calculates a difference value of D(n)=S(n)&#x2212;B(n). When the concentration of the gas is increased so that the difference value becomes greater than a predetermined concentration threshold, a high concentration signal is generated to close a flap () and a base value B(n) is calculated by using a coefficient kwhich is smaller than kbased on B(n)=B(n&#x2212;1)+k{S(n)&#x2212;B(n&#x2212;1)}.

Gas detector and automobile ventilation system

A gas detection apparatus incorporating a gas sensor element and a vehicle automatic ventilation system including the apparatus in which a sensor output value S(n) is obtained, and a base value B(n) is calculated by use of Expression (1): B(n)=B(n&#x2212;1)+k1[S(n)&#x2212;B(n&#x2212;1)]&#x2212;k2[S(n)&#x2212;S(n&#x2212;5)] in the case where S(n)&#x2267;B(n&#x2212;1), or by use of Expression (3): B(n)=S(n) in the case where S(n)&#x3c;B(n&#x2212;1), followed by calculation of a difference value D(n); i.e., S(n)&#x2212;B(n). When the difference value exceeds a predetermined high connection threshold, a high-concentration signal is generated to close a flap. After that, the base value B(n) is calculated by use of Expression (4): B(n)=B(n&#x2212;1)+k3[S(n)&#x2212;B(n&#x2212;1)]&#x2212;k4[S(n)&#x2212;S(n&#x2212;5)]. When the difference value becomes smaller than a predetermined low-concentration threshold, a low-concentration signal is generated to open the flap.

Gas detection apparatus and automatic ventilation system for vehicle

A control system for a gas sensor element capable of lessening the effect of variations in sensor properties among gas sensor elements as well as the effect of environmental factors, such as temperature and humidity, to thereby accurately detect variation in the concentration of a specific gas. In a control system for a gas sensor element whose sensor resistance Rs varies with the concentration of NOx gas, a pulse signal Sc which alternates between 0 V and &plus;5 V is input to a pulse input terminal When a voltage of 5 V is applied to the pulse input terminal a capacitor is charged via a fixed resistor having a resistance Rc and a diode When a voltage of 0 V is applied, the capacitor discharges via the gas sensor element An output voltage Vout is A/D-converted and processed by means of a microcomputer thereby controlling an electronic control assembly The potential Vout at an operating point Pd varies with the sensor resistance Rs as well as with the duty ratio DT of the pulse signal Sc. Thus, the output voltage Vout can be maintained within a predetermined range by adjusting the duty ratio.

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Aichi, Japan

Yuji Kimoto