Abstract: A combustion system for reducing an amount of air polluting substances in a combustion exhaust gas produced in a combustion furnace comprises a combustion furnace configured to produce a combustion exhaust gas upon combustion of a combustible material, wherein the combustion exhaust gas contains an amount of air polluting substances; an analyzer suitable for analyzing the combustion exhaust gas and producing an analytical signal; a conduit suitable for conducting the combustion exhaust gas from the outlet opening to the analyzer, wherein the conduit is located adjacent the outlet opening of the combustion furnace; a controller suitable for processing the analytical signal produced by the analyzer and outputting a first control signal and a second control signal, based on the analytical signal; a neutralizer supplier suitable for supplying the combustion furnace with an amount of neutralizers to reduce the amount of air polluting substances in the combustion exhaust gas, wherein the amount of neutralizers supp

Abstract: A control system for an internal combustion engine has a canister for adsorbing evaporative fuel generated in the fuel tank, a purging passage extending between the canister and the intake system of the engine, for purging evaporative fuel into the intake system, and a purge control valve arranged across the purging passage, for controlling the flow rate of evaporative fuel supplied to the intake system through the purging passage. An ECU controls the engine, based on at least one predetermined engine control parameter, and a canister temperature sensor detects the temperature of the canister. The at least one predetermined engine control parameter is changed according to the detected temperature of the canister.

Abstract: An automatic exhaust gas analyzer for analyzing an exhaust gas of an internal combustion engine. The analyzer includes: a) plural analyzing units; b) two independent gas lines provided in each of the plural analyzing units; c) a gas-chromatographic column provided in each of the gas lines; d) a gas-chromatographic detector connected with the column in each of the gas lines; and e) a signal communication network interconnecting the gas-chromatographic detectors. Exhaust gas and the background gas are sampled at each stage of a predetermined run cycle, and are provided immediately to the two independent gas lines of the plurality of analyzing units respectively. Then the exhaust gas and background gas are analyzed in parallel in each of the plurality of analyzing units, which facilitates equalizing the measurement conditions of the two gases and the background correction of the measurement results of the exhaust gas can be made at high precision.

Abstract: An air-fuel ratio control system for an internal combustion engine mounted on a vehicle with a transmission, including an oxygen concentration sensor producing an output signal whose level is substantially proportional to an oxygen concentration of the exhaust gas, effects a feedback control of the air-fuel ratio of mixture to be supplied to the engine toward a target value determined on the basis of various parameters of the engine operation and corrected in response to a magnitude of atmospheric pressure, so that the higher a shift position of the transmission gear is, the leaner the target air-fuel ratio becomes. Thus, the fuel consumption in a light load operating condition of the engine is decreased and the driveability of the vehicle is improved.

Abstract: An oxygen concentration sensing apparatus includes an oxygen pump element and a sensor cell element to be placed in a gas under measurement, and a device for generating a voltage value command indicating a voltage to be generated across electrodes of the sensor cell element. A current limit device is provided so that the supply of the voltage value command is stopped to decrease a pump current to the oxygen pump element gradually when the voltage generated across the electrodes of the sensor cell element exceeds a first predetermined voltage, and the pump current to the oxygen pump element is reduced immediately when the voltage generated across the electrodes of the sensor cell element exceeds a second predetermined voltage which is higher than the first predetermined voltage.

Abstract: An air intake side secondary air supply system for an internal combustion engine having an air intake side secondary air supply system includes an oxygen concentration sensor, and controls a duty ratio of opening and closing of an open/close valve disposed in the air intake side secondary air supply passage by determining a valve open period within each duty cycle of control operation in accordance with a result of comparison between the level of the output signal of the oxygen concentration sensor and a level corresponding to a target air-fuel ratio. The duty ratio of opening and closing of the open/close valve is maintained within a predetermined duty ratio range so as to improve effectiveness of the control of the secondary air supply as well as to avoid the generation of over lean or over rich mixture.

Abstract: An oxygen concentration sensing apparatus includes an oxygen pump element and a sensor cell element with a pair of electrodes respectively, being disposed to face each other, to form a restricted region between them, and a current source for supplying a pump current across the electrodes the oxygen pump element. A limit voltage is adjustably set in response to a voltage across the electrodes of the oxygen pump element, and the pump current supplied to the oxygen pump element is reduced when a voltage generated across the electrodes of the sensor cell element has exceeded the limit voltage.

Abstract: The valve opening of an exhaust gas recirculating valve is controlled in response to operating conditions of the engine so as to regulate the amount of exhaust gas recirculation to values appropriate to the operating conditions of the engine. The valve opening of the exhaust gas recirculating valve is varied by a predetermined value when the engine is determined to be in a predetermined accelerating condition or a predetermined decelerating condition. Further, the predetermined value is corrected in accordance with the detected shift lever position. Preferably, the valve opening of the exhaust gas recirculating valve is increased or decreased by a predetermined incremental value or a predetermined decremental value when the engine is in the predetermined accelerating condition or the predetermined decelerating condition, and the predetermined incremental value or the predetermined decremental value is corrected in accordance with the detected position of the shift lever.

Abstract: A method for directing an up shift operation for a vehicle having an engine and a manual transmission generates a direction of an up-shift operation when the vehicle speed exceeds a reference speed determined for each gear position. The reference speed of a medium speed gear is varied according to the degree of acceleration at the time of the previous up-shift operation. If the up-shift operation from a low speed gear to the medium speed gear is effected while the vehicle is not accelerating rapidly, the reference speed for an up shift operation from the medium speed gear is lowered. Further, if a cruising state of the vehicle with the medium speed gear after the acceleration is continued for more than a predetermined time period, the reference speed for an up-shift operation from the medium speed gear is also lowered.

Abstract: An air intake side secondary air supply system for an internal combustion engine has an air intake system using a carburetor and an air intake side secondary air supply passage leading downstream of the carburetor. The passage includes an oxygen concentration sensor producing an output signal whose level is substantially proportional to an oxygen concentration of the exhaust gas. A control means for controlling a flow control valve is disposed in the air intake side secondary air supply passage and operates in accordance to the output signal of the oxygen concentration sensor. In a variation of the invention, the feedback control of air-fuel ratio using the output signal of the oxygen concentration sensor is effected only when the engine operational state is in a predetermined operational region.

Abstract: An air intake side secondary air supply system for an internal combustion engine having an air intake side secondary air supply passage and an O.sub.2 sensor controls a duty ratio of opening and closing of an open/close valve disposed in the air intake side secondary air supply passage in accordance with a detected air-fuel ratio of mixture by means of an output signal of the O.sub.2 sensor. The system sets a base valve open period of the open/close valve every predetermined period and decreases the base valve open period by a first predetermined correction amount when the detected air-fuel ratio is leaner than a target air-fuel ratio, and increases the base valve open period by a second predetermined correction amount when the detected air-fuel ratio is richer than the target air-fuel ratio.

Abstract: An air intake side secondary air supply system for an internal combustion engine having an air intake system using a carburetor and an air intake side secondary air supply passage leading to the downstream of the carburetor, and equipped with a fuel increment control system. The system includes an oxygen concentration sensor producing an output signal whose level is substantially proportional to an oxygen concentration of the exhaust gas, and an open/close valve disposed in the air intake side secondary air supply passage controlled in accordance the output signal of the oxygen concentration sensor. The system is adapted close the open/close valve continously to stop the air/fuel ratio control when an operation of the fuel increment control system is detected.