Abstract: It is intended to detect combustion state of an internal combustion engine over the entire range where positive torque is generated. Time required from a predetermined first crank angle to a second crank angle is measured by detecting a rotation angle of a ring gear or plate with engine speed detecting means 101. Then, a combustion state parameter is calculated from said required time by combustion state detecting means 102 with an established calculation method, and combustion state is determined by combustion state judging means 103. Engine speed correction means 104 determines and feeds back a correction value for the combustion state detecting value to correct the engine speed. At the moment, the correction quantity for correcting the required time is varied so that the normal combustion value of said combustion state parameter is at a predetermined value or less, or within a predetermined range.

Abstract: A conversion efficiency of a catalyst is determined by a cross correlation function of a cross-correlation between an output of an oxygen sensor at the upstream of the catalyst and an output of an oxygen sensor at the downstream of the catalyst, to thereby monitor deterioration index of the catalyst. Then, an air and fuel ratio is obtained from at least one of the outputs of the two oxygen sensors, to thereby adjust a fuel supply quantity, so that the fuel supply quantity can be controlled even during a period when the catalyst is being analyzed, without deviating the air and fuel ratio from a target air and fuel ratio.

Abstract: A diagnosis apparatus for diagnosing a catalytic converter of a motor vehicle as to whether the catalyst suffers deterioration by estimating a temperature of the catalyst or that of the exhaust gas in the vicinity of the catalyst on the basis of a plurality of engine parameters to thereby decide deterioration of the catalyst by using as an index the estimated temperature. The apparatus includes a unit for estimating the temperature of the catalyst in a steady state by making use of an engine speed and an engine load which represent typical parameters employed in fuel injection control of the engine. The steady-state temperature facility is realized by storing the engine speeds and the engine loads obtained experimentally in the steady state operation of the engine in the form of a two-dimensional data map.

Abstract: This invention performs a diagnosis on the evaporative system in a short period of time by pulling down the evaporative system with a negative pressure of the intake manifold of the engine and by checking a change in the internal pressure of the evaporative system being pulled down. To realize this diagnosis, when introducing a negative pressure from the intake manifold, the pulldown rate is changed based on the internal pressure of the evaporative system. Because the pulldown rate is corrected and controlled during the diagnostic process, a preliminary process for the diagnosis can be eliminated, shortening the time required for the diagnosis. Further, this method allows the evaporative system to be diagnosed without being influenced by external factors such as atmospheric pressure, the internal volume of the evaporative system, the amount of evaporative gas generated, or presence or absence of leakage.

Abstract: A diagnosing system of a catalytic converter in an internal combustion engine has a detecting unit to detect an operating state of the engine and an air/fuel ratio control unit to adjust a fuel injection amount so as to keep an air/fuel ratio of a mixture that is inhaled into the engine to a target value. The operating state of the engine is detected, whereby it is confirmed that the engine lies in a predetermined operating region to execute a catalyst diagnosis on the basis of the detected operating state. In each of a plurality of different catalyst diagnosis regions, the performance of the catalytic converter or the performance of the catalytic converter array is diagnosed on the basis of the output signal of the first exhaust gas component sensor arranged on the upstream side of the catalytic converter array and the output signal of the second exhaust gas component sensor arranged on the downstream side.

Abstract: A diagnostic apparatus for exhaust gas clarification apparatus for internal combustion engine is disclosed. The diagnostic apparatus can diagnoses the individual catalyst independently by means that an air/fuel ratio sensor is mounted before and after the individual catalyst, and that the individual catalyst is diagnosed by estimating the correlation of the output signals from the air/fuel ratio sensors mounted before and after the individual catalyst, and furthermore, that the individual diangosis operation is performed at distinctive operation regions adequate for their corresponding diagnostic mode.

Abstract: A diagnostic system in which the accuracy of the diagnosis of the deterioration state of a catalyst in a catalytic converter for cleaning the exhaust gas of an internal combustion engine is enhanced without incurring a rise in cost. The temperature of the catalyst is estimated using the operating-state signal (for example, the flow rate of intake air or the width of a fuel injection pulse) of the engine by a diagnostic device. The conversion efficiency of the catalyst calculated from the outputs of oxygen sensors is corrected using the estimated temperature by the diagnostic device. The deterioration state of the catalyst is diagnosed on the basis of the corrected temperature by the diagnostic device.

Abstract: In an evaporated fuel gas purging system, an accurate diagnosis can be realized by providing a reference leakage apparatus (a gauge) having a preset amount of leakage, by intentionally causing a known leakage using the gauge means under the same condition of diagnosing a leakage, and by comparing the pressure change with the pressure change in using the reference leakage apparatus. In the process of diagnosing leakage by depressurizing or pressurizing and closing the inside of the evaporated fuel gas purging system so as to leave it under presence of pressure differences to the atmospheric pressure and then by detecting the pressure change, a difference occurs in the pressure changes inside the evaporated fuel gas purging system between when the gauge is opened and closed. Then sensitivity of the difference in the pressure changes to the leakage is improved under the condition during diagnosis such as fuel temperature, atmospheric pressure, amount of remaining fuel, fuel properties and so on.

Abstract: A malfunction monitoring apparatus for a secondary air supply system of an internal combustion engine includes an air flow sensor for measuring the flow rate of an air flowing into an intake air path of the engine, a secondary air introducing path disposed in the intake air path on the downstream side of a measuring position of the air flow rate for taking in a part of the air through the intake air path as a secondary air, a secondary air supply device for supplying the secondary air to an exhaust gas path, and a control unit. The apparatus may further include a pressure sensor for detecting the internal pressure of an intake manifold.

Abstract: A multi-media information transfer system transfers information between a computer center and a multi-media mail apparatus which is coupled to a communication network. The multi-media information transfer system includes a first part provided in the computer center and the multi-media mail apparatus for specifying a transfer mode based on an attribute of information which is to be transferred, a second part provided in the multi-media mail apparatus for storing information which is received from the computer center and the communication network, and a third part provided in the computer center and the multi-media mail apparatus for transferring the information between the computer center and the multi-media mail apparatus in the transfer mode specified by the first part.

Abstract: Provided is an internal combustion engine malfunction diagnosis apparatus capable of diagnosing the deterioration of an internal combustion engine with a high accuracy and capable of diagnosing deterioration of a fluctuation factor detection section of the engine with a high accuracy in irrespective of the engine speed.

Abstract: A diagnostic system in which the accuracy of the diagnosis of the deterioration state of a catalyst in a catalytic converter for cleaning the exhaust gas of an internal combustion engine is enhanced without incurring a rise in cost. The temperature of the catalyst is estimated using the operating-state signal (for example, the flow rate of intake air or the width of a fuel injection pulse) of the engine by a diagnostic device. The conversion efficiency of the catalyst calculated from the outputs of oxygen sensors is corrected using the estimated temperature by the diagnostic device. The deterioration state of the catalyst is diagnosed on the basis of the corrected temperature by the diagnostic device.

Abstract: The invention provides an internal combustion engine misfire detection device for a motor vehicle in which an output of an internal combustion engine is transmitted via a torque converter to a drive shaft. A primary misfire detecting unit detects an internal combustion engine misfire condition including a possible false condition thereof; and an external cause detecting unit detects an influence associated with an external cause variation in terms of an operating condition variation transmitted from the drive shaft via the torque converter. A misfire judging unit judges whether the internal combustion engine misfire condition detected by the primary misfire detecting unit is a true misfire condition or a false misfire condition based on the detection output from the external cause detecting unit.

Abstract: A system for accurately diagnosing the combustion condition of a multicylinder engine from the fluctuation of revolution speeds among individual cylinders in a wide range of engine revolution speeds, comprising a functional pattern storage which stores therein a functional pattern on the fluctuational error of a combustion condition parameter corresponding to the variation of the revolution speeds; a learning unit which specifies the functional pattern on the basis of the revolution speeds and the combustion condition parameter successively for the respective cylinders while making corrections if necessary, and which evaluates the fluctuational error of the combustion condition parameter for the revolution speed of a predetermined one of the cylinders; and a correction unit which subtracts the evaluated fluctuational error from the combustion condition parameter for the predetermined cylinder, and which sets the difference of the subtraction as a new combustion condition parameter.

Abstract: The present specification discloses a control system for an automobile. An automobile control system according to the present invention is provided in an automobile and includes control devices for controlling the automobile in accordance with data on a control characteristic, and a rewritable storage device for storing a plurality of pieces of data on the control characteristics of the control devices and different drivers in corresponding relationship. In response to an input from any particular driver, data on control characteristic corresponding to the particular driver is read from the storage when the particular driver who has input data is the one stored in the storage, and the data is delivered to the control devices. The data on the control characteristic in the storage which the particular driver specifics can be corrected arbitrarily in accordance with a correcting input.

Abstract: A catalytic diagnostic apparatus for determining whether a catalyst of an internal combustion engine has deteriorated as disclosed. Air-fuel ratio sensors are placed at the upstream and downstream sides of the catalytic converter, and the output signal from the upstream air-fuel sensor is used to control the air-fuel mixture provided to the engine via the fuel injectors, in a conventional closed loop operation. Diagnosis of the condition of the catalytic converter is performed only when selected engine operating parameters fall within a predetermined diagnostic range. When the engine is operated in the diagnostic range, the condition of the catalytic converter is analyzed by calculating a deterioration index based on a comparison of the variation of the output signals from the upstream and downstream air-fuel ratio sensors.

Abstract: An apparatus for combustion condition diagnosis has an ionic current detecting circuit for measuring a voltage at the secondary side of the ignition coil of an engine during a plurality of time periods during one operation cycle including a period in which an internal pressure of a cylinder of the engine becomes maximum, under a normal combustion condition. A window generation circuit is provided for establishing the time periods, an integration circuit is provided for integration processing of the measured voltage during each time period, a ROM stores a list indicating combustion condition corresponding to the integrated value for the each time period, and a CPU diagnoses the combustion condition based on the integrated value for the each time period and the list of combustion conditions, in order to decrease erroneous judgement and perform more adequate combustion condition diagnosis.

Abstract: A method for controlling coating weight on a hot-dipped steel strip comprises the steps of positioning at least one pair of high-frequency (alternating) current conducting paths near one side of a steel strip and near another side of the steel strip drawn out of a coating bath, each of the high-frequency (alternating) current conducting paths being parallel with a surface of the steel strip above the coating bath, and flowing a-high-frequency (alternating) current strong enough to magnetically saturate the steel strip through the at least one pair of high-frequency (alternating) current conducting paths to induce a high-frequency (alternating) current of an opposite phase in the steel strip, a magnetic pressure acting on surfaces of the steel strip being generated by an interaction of the induced high-frequency (alternating) current with a high-frequency (alternating) current of the high-frequency (alternating) current conducting paths.

Abstract: A system which is capable of diagnosing the deterioration condition of an engine exhaust gas purifying device has front and rear air/fuel ratio sensors for detecting the air/fuel ratio of the exhaust gas upstream and downstream of the catalyst, an autocorrelation function calculation for calculating the autocorrelation function .phi.xx of an output signal from the front air/fuel ratio sensor to output the maximum values (.phi.xx)max of the autocorrelation function .phi.xx at predetermined intervals, each maximum value (.phi.xx)max being in each of the predetermined intervals. A cross-correlation function calculator calculates the cross-correlation function .phi.xy between the output signals from the front and rear air/fuel ratio sensors to output the maximum values (.phi.xy)max of the mutual correlation function .phi.xy at predetermined intervals, each maximum value (.phi.xy)max being in each of the predetermined intervals therefore. The ratios between the maximum values (.phi.xy)max and (.phi.

Abstract: A conversion efficiency of a catalyst is estimated by a correlation function concerning output signals of upper and down stream side air fuel ratio sensors. The conversion efficiency is measured by comparing the correlation function and a complementary value of the correlation function with a comparing standard value.