Mitsubishi Denki Kabushiki Kaisha

Mitsubishi Denki K.k.

Takanori Fujimoto

Toshiro Hara

Toshirou Hara

Satoshi Komurasaki

Yasuo Tada

Koji Nishimoto

Yoshiaki Kanno

Masahira Akasu

Ikuo Musa

Hiroyasu Kisaichi

A misfire detecting device for an internal combustion engine including an ion current detecting means for detecting ion currents generated between electrodes of spark plugs; an ion current judging means for judging whether or not the ion current exists at each ignition cycle based on the ion current signal; a misfire judging means judging when no ion current is judged to exist based on an ion current judgment signal; an ignition coil; an ignition coil signal judging means for judging whether or not the ignition coil signal generated in synchronism with an ignition timing exists; and a failure judging means for judging whether or not an failure of the ion current detecting means occurs based on a result from the ignition coil signal judging means when the ion current signal is not detected.

Misfire detection device for internal combustion engine

The contents of a ROM are highly reliably changed while the ROM is attached to a substrate. A vehicle control device has an electrically programmable nonvolatile memory storing a vehicle control program. A ROM update process includes a collation in which a check is made to determine whether the updating of the ROM was correctly executed. An abnormal process ensures an output from the control device clearly is an abnormal control amount under even ordinary vehicle drive conditions.

Vehicle control device

A vehicle control device has an PROM with a first and second memory area. The contents of the PROM are updated by erasing locations for a vehicle control program, writing part of the vehicle control program into the PROM, checking for abnormalities in the writing process, and then writing the remaining part of the vehicle control program into the PROM only when the result of writing the part first is determined not to have been abnormal. This determination may be based on a checksum, of the program codes that were expected to have been written into the first memory area as the first part of the vehicle control program, compared with the checksum of the program codes actually written. In the event of an abnormality, only the part of the vehicle control program first written is in the PROM, and the area in which the remaining part of the vehicle control program would have been written remains erased. The remaining part of the vehicle control program is a part of the program necessary for proper functioning, such as the reset vector. If the reset vector of the vehicle control program is used as the remaining part, and the remaining part is not written due to the detection of an abnormality, then any attempt to execute the abnormally updated control program will result in performance that is manifestly abnormal and easy to detect in subsequent production steps.

A throttle valve full-closure detecting system for an internal combustion engine which is capable of surely detecting a fully closed state of a throttle valve and further of preventing the occurrence of troubles when an accelerator pedal is released from the state where the driver lightly places his foot thereon. The throttle valve full-closure detecting system comprises a full-closure detecting unit 6 for detecting the fully closed state of the throttle valve 1, and a throttle sensor 5 for sensing a throttle opening degree .theta. of the throttle valve 1. Further included in the system are a throttle full-closure detecting and storing unit 11 for averaging the throttle opening degrees to store it as a full-closure throttle opening degree o when the full-closure detecting unit 6 detects the fully closed state of the throttle valve 1 and a a throttle valve full-closure decision unit 12 for detecting that the throttle valve 1 is in the fully closed state when the full-closure detecting unit 6 detects the fully closed state of the throttle valve 1 and the throttle opening degree is below an opening degree obtained by adding a predetermined value to the full-closure throttle opening degree.

System for detecting fully closed state of the throttle valve for use in

A common type engine controller controlling an automotive engine in accordance with the kind of the associated transmission (i.e., automatic or manual) includes an electronic control unit 54 consisting of a microcomputer. When used with an automatic transmission, the power supply circuit includes a neutral switch 53 inserted between the starter switch 51 of the vehicle and the magnet coil 52 controlling the current supply to the starter motor, wherein the starter signal S.sub.T is supplied to the electronic control unit 54 from the junction between the neutral switch 53 and the magnet coil 52, the neutral signal N.sub.T being supplied from the junction between the starter switch 51 and the magnet coil 52 (FIG. 2 ). When used with a manual transmission, on the other hand, the starter signal S.sub.T is supplied from the junction between the starter switch 51 and the magnet coil 52, and the neutral signal N.sub.T is grounded. Upon detecting the high level of the starter signal S.sub.T, the electronic control unit 54 determines the kind of the associated transmission based on the level of the neutral signal N.sub.T.

Common type engine controller for controlling automotive engine in

An apparatus for controlling the idling rotation of an engine comprises a generator driven by the engine for charging a battery for supplying DC power to electrical loads, a switching circuit for controlling an exciting current flowing through a field coil of the generator to keep the voltage of the battery substantially constant, and a control circuit for controlling an amount of suction air sucked into the engine. The control circuit includes a detection circuit for detecting a total excitation period C.sub.pr of the field coil in every predetermined crank angle cycle and a computer for computing a correction amount P.sub.E of air sucked in the engine in response to the detected total excitation period C.sub.pr.

Apparatus for controlling idling rotation of engine

A misfire sensing apparatus for an internal combustion engine can determine an occurrence of misfiring in any of engine cylinders as well as which cylinder is misfiring with improved accuracy and reliability. A crank angle sensor 11 generates an output signal at predetermined crank angles of the engine. A control unit 20 identifies operating states of the cylinders based on the output signal from the crank angle sensor. It successively senses misfire information in the form of the number of revolutions per minute of the engine at the predetermined crank angles, and determines possible misfiring in a cylinder when a difference between the current misfire information and the previous one is greater than a predetermined level. When there is possible misfiring in a cylinder, the control unit adjusts an engine operating parameter by a predetermined value, compares misfiring information as sensed before and after the adjustment, and determines an occurrence of true misfiring if a difference in the misfiring information before and after the adjustment is less than a predetermined reference value. In one form, the control unit decreases, upon occurrence of possible misfiring in a cylinder, an amount of fuel supplied to that cylinder so as to cause intentional misfiring therein. In another form, the control unit stops, upon occurrence of possible misfiring in a cylinder, firing of a spark plug for that cylinder.

Misfire sensing apparatus for an internal combustion engine

An apparatus for controlling an engine idling rate comprises first correction means for correcting the engine idling rate according to the excitation period in each predetermined cranking period for driving a generator of the engine. A second correction means corrects the predetermined cranking period according to the engine idling rate, and suppresses variations of the engine idling rate.

Apparatus for controlling idling revolving rate of engine

An idling engine speed controlling apparatus for an engine having a generator driven by an engine to charge a battery, a switching means for controlling the supply and interruption of an exciting current to a field winding for the generator so that a voltage generated from the generator or a voltage of a battery becomes a predetermined level, a continuous detecting means for detecting a total excitation time of the field winding during each rotational time period, and a regulator means having a control unit responsive to an output of continuous detecting means for adjusting a quantity of intake air supplied to the engine by detecting an excitation time of the field winding for each time period of the engine.

Idling engine speed controlling apparatus for an engine

An air-fuel ratio controller which detects oxygen content of the engine exhaust gases, compares the detected value with an objective oxygen content corresponding to an objective air-fuel ratio and integrates the deviation therebetween, smoothes the integrated values to absorb errors in control caused by variations in an injector or the like, and controls the air-fuel ratio in accordance with such integrated and smoothed values. The air-fuel ratio controller always controls the air-fuel ratio properly by stopping the smoothing of the integrated values when, for example, the detected oxygen content is disordered, and the detected values do not vary remarkably for more than a predetermined period.

Air-fuel ratio controller

A fuel controller for an internal combustion engine senses misfiring in an engine cylinder by sensing changes in the rotational speed of the engine between prescribed crankshaft angles due to a reduction in torque when misfiring occurs. When misfiring occurs, the supply of fuel to the misfiring cylinder is cut off for a prescribed number of engine rotations and then the supply of fuel is restarted. A warning indicator is turned on as long as misfiring is detected by the misfiring sensor.

Fuel controller for internal combustion engine

A fuel controller for an internal combustion engine has a crank angle sensor which generates a cylinder recognition signal corresponding to a prescribed cylinder of the engine. If a microcomputer 12 determines that the cylinder recognition signal has not changed during the occurrence of a prescribed number of changes in the level of a crank angle signal, the cylinder recognition signal is determined to be abnormal and fuel injectors of the engine are not actuated if the engine has been running for at least a prescribed length of time, thereby cutting off the supply of fuel to the engine.

Fuel controller for an internal combustion engine

Method for controlling the operation of an engine for a vehicle

A fuel control system for an internal combustion engine for controlling fuel supply rate on the basis of the output signal of a vortex flowmeter having variable-frequency filter means, capable of accurately measuring intake air flow to control the fuel supply rate accurately avoiding the erroneous measurement of noises generated during the rapid deceleration of the engine in which the throttle valve is shut. The fuel supply system has operating mode detecting means for detecting the operating mode of the engine, and passband fixing means for fixing the passband of the variable-frequency filter means at a predetermined passband when the operating mode detecting means detects that the engine is in a predetermined deceleration mode. The passband of the variable-frequency filter means is fixed at the predetermined passband while the engine is in the predetermined deceleration mode to enable accurate control of fuel supply rate by eliminating noise signals which is generated during the predetermined deceleration mode and superposed on the operating mode detection signal. When the engine is accelerated during a time period subsequent to the end of the predetermined deceleration mode, the fixation of the passband of the variable-frequency filter means is cancelled.

Fuel control system

An engine control apparatus comprises a cylinder discrimination sensor for generating cylinder discrimination signal, a crank angle sensor for generating crank angle signal, a fuel injection valve provided in each cylinder of the engine, an ignition coil provided in correspondence to each and every cylinder, a flip-flop circuit for detecting a state of misfire in each cylinder on the basis of a state of signal of said ignition coil, and a micro-computer for receiving the cylinder discrimination signal, the crank angle signal and the output signal of the flip-flop circuit to detect that a state of misfiring has occured continuously at the same cylinder and for closing the fuel injection valve corresponding to the cylinder where the misfiring has occured.

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Himeji, Japan

Takanori Fujimoto