Abstract: A sensor system includes a single sensor means, two sensed signal processing circuits for processing the output signal of the sensor means, both the signal processing circuits being substantially equal in circuit construction, and an abnormality detecting circuit for detecting an abnormality on the basis of the difference between the output signals of the two sensed signal processing circuits.

Abstract: The invention provides a sensing device capable of outputting a high-accuracy signal precisely corresponding to a particular position (angle) of a rotating member made of a magnetic material without being disturbed by external noise. The sensing device includes: a magnet for generating a magnetic field; a rotating member made of a magnetic material, for changing the magnetic field generated by the magnet, the rotating member being disposed a predetermined distance apart from the magnet; and a giant magnetoresistance device whose resistance changes in response to the change in the magnetic field caused by the rotating member of magnetic material, wherein the size L.sub.3 of the magnetic field sensing plane of the giant magnetoresistance device is set to a value less than the smallest value of the dimensions L.sub.1 and L.sub.2 of the protruding and recessed portions of the rotating member of magnetic material, that is, the size L.sub.

Abstract: A combustion state detecting apparatus for an internal-combustion engine permits an improved signal-to-noise ratio of a knocking signal with a resultant improved controllability without adding to the load on an electronic control unit (ECU). The combustion state detecting apparatus is equipped with: a knocking signal processing circuit 20 which generates a knocking signal (K) according to an ionic current detection signal (Ei); and an ECU (2A) which detects the combustion state at a spark plug according to the ionic current detection signal and the knocking signal.

Abstract: In an ignition controller for an internal combustion engine, an angle sensor includes a plurality of sensor means for individually outputting a pulse signal SGT1 corresponding to a first reference crank angle and a pulse signal SGT2 corresponding to a second reference crank angle and a control/arithmetic operation circuit includes a timing calculation means for calculating the timings at which ignition coils are controlled according to an operating state, count means for counting the number of the pulses of one of respective pulse signals which are detected between two continuous pulses of the other of them, reverse rotation discriminating means for discriminating the reverse rotation of the internal combustion engine based on the count values CA1 and CA2 of the respective pulse signals and control prohibition means for prohibiting the output of drive signals P1 and P2 in response to a reverse rotation discriminating signal to thereby prohibit ignition control in the occurrence of the reverse rotation by disc

Abstract: A control apparatus for an internal combustion engine capable of optimizing a control parameter for the engine on the basis of information concerning combustion state of the engine by making use of a detected ion current which changes with a high sensitivity in dependence on combustion state within an engine cylinder, for thereby realizing an engine operation control to reduce fuel cost without degrading a control performance for obtaining a high engine output and drivability of a motor vehicle equipped with the engine.

Abstract: A combustion state detecting apparatus for an internal combustion engine capable of detecting combustion state in the engine with high accuracy and reliability by deriving an ion current detection signal which is based on only an ion current by canceling out a leakage current component. The apparatus includes a high-voltage diode (11a, . . . , 11d) connected to a spark plug (8a, . . . , 8d), a bias voltage applying circuit (9) for applying a bias voltage (VBi) to the spark plug by way of the high-voltage diode, an ion current detecting circuit (12) for detecting an ion current (i) flowing through the spark plug immediately after ignition to thereby output an ion current detection signal (Ei), an electronic control unit (2) for determining combustion state of the engine on the basis of the ion current detection signal (Ei), and a leakage current compensating means (21, 22) connected in parallel with the ion current detecting means (12).

Abstract: A cylinder discriminating device includes a ratio computing device for computing the ratio between the periods of signal generation over predetermined two sections, a signal group discriminating device for discriminating a predetermined group of signals, and a signal discriminating device for discriminating a predetermined signal from the group of signals. Thus, the cylinder discriminating device can be provided which does not provide erroneous decision in cylinder discrimination in a signal generating device in a single system, but can shorten the time required for cylinder discrimination to effect inherent control for each cylinder.

Abstract: A misfire detecting apparatus for an internal combustion engine which can ensure enhanced reliability for detection of the misfire event by suppressing the so-called after-burning ion current generated in an engine cylinder controlled in precedence and superposed on a normal or regular ion current generated in a cylinder controlled in succession. The apparatus includes a bias voltage supplying means (9a, 9b) for applying a bias voltage (VBi) to the spark plugs (8a to 8d) by way of the high-voltage diodes (11a to 11d), an ion current detecting means for detecting ion currents (i) flowing through the spark plugs and an electronic control unit (2) for driving the ignition coil (4) and determining misfire event in the internal combustion engine on the basis of the ion current detection signal (Gia, Gib). The ion current detecting means includes a plurality of ion current detecting circuits for detecting ion currents in the engine cylinders belonging to a plurality of cylinder groups.

Abstract: A controller for a four-stroke cycle internal-combustion engine, which has a single sensor mounted on a crankshaft and employs a single sequence of position signal pulses corresponding to crank angles, achieves reduced cost and higher accuracy even for an engine with an odd number of cylinders. For each revolution of the crankshaft, a position signal pulse is issued from the sensor mounted on the crankshaft; the position signal pulse includes a reference position signal pulse in a number which is a multiple of N of the number of cylinders and a cylinder identifying signal pulse for a particular cylinder every time the crankshaft rotates.

Abstract: A knock control system for an internal combustion engine which subjects a knock signal waveform superposed on an ionic current to pulse processing so as to improve a signal-to-noise (SN) ratio, thereby achieving higher reliability thereof without adding to cost. The knock control system for the internal combustion engine is equipped with: a device for deciding the ignition timing for each cylinder based on a crank angle signal; an ignition coil which applies high voltage to spark plugs according to the ignition timing; a device for detecting an ionic current flowing through an ignited spark plug; a device for detecting a knock from an ionic current detection signal; a device for correcting the ignition timing by delaying it when a knock has been detected; a waveform processing device for extracting a knock signal waveform from the ionic current detection signal in the form of a knock pulse string; and a counter for counting the number of pulses from the pulse edges of the knock pulse string.

Abstract: To correctly sense combusting conditions of an internal combustion engine, an ion current caused by combustion is detected.

Abstract: An engine control apparatus for an internal combustion engine capable of rapidly and easily identifying engine cylinders with high accuracy, while ensuring a backup control upon occurrence of an abnormality. The control apparatus includes a first signal detector provided in association with a crank shaft for obtaining a first signal series, a second signal detector provided in association with a cam shaft for obtaining a second signal series, and a controller for controlling a parameter involved in engine operation on the basis of each signal series. The first signal series includes an angular position signal and level intervals corresponding to cylinder groups, while the second signal series includes cylinder identifying signal pulses. The pulse identifying a given cylinder has a form which differs from those for the other cylinders.

Abstract: A control apparatus for an internal combustion engine capable of performing engine cylinder identification while ensuring a backup control upon occurrence of abnormality includes a first detector 81 for generating a first signal series REFC synchronously with rotation of a crank shaft 11, a second detector 82 for generating a second signal series POSC synchronously with rotation of a cam shaft 1, and a microcomputer 100 for controlling a parameter P for the engine from the first or second signal series. The first signal series REFC contains reference position pulses indicative of reference positions .theta.R for cylinders. One of the pulses corresponding to a given cylinder group (#1, #4) has a shape PW1 differing from that for the other group (#2, #3). The second signal series contains angular position pulses generated at every predetermined position of the cam shaft and a cylinder identifying signal .tau. corresponding to cylinder (#1). The microcomputer detects a reference position .theta.

Abstract: A control apparatus for an internal combustion engine which is capable of performing engine cylinder identification rapidly, easily and inexpensively, while capable of performing a backup control upon occurrence of abnormality in a first signal series containing an angular position signal. The control apparatus includes a first signal detector for generating a first signal series in synchronism with a rotating shaft of the engine, a second signal detector for generating a second signal series in synchronism with the rotating shaft and a control means for controlling parameter on the basis of the first and second signal series. The first signal series includes an angular position signal and a constant level signal corresponding to a reference position for a specific cylinder group.

Abstract: An engine control signal generating apparatus of an internal combustion engine which is capable of performing engine cylinder identification economically, rapidly and easily with high accuracy, while performing a backup control upon occurrence of abnormality. The control apparatus includes a first signal detector (81) provided in association with a crank shaft (11) for obtaining the first signal series, a second signal detector (82) provided in association with a cam shaft (1) for obtaining a second signal series (SGC) and a control means (100) for controlling parameter (P) involved in operation of the engine on the basis of each signal series. The first signal series includes an angular position signal and a reference position signal for each of the engine cylinders, while the second signal series includes cylinder identifying signal pulses. The pulse(s) identifying a specific cylinder or the specific cylinder group differ from those of the other engine cylinders or cylinder groups.

Abstract: A magnetoresistance type sensor device for detecting an angle or strength of a magnetic field applied thereto includes first to fourth magnetoresistance elements interconnected so as to constitute a Wheatstone bridge circuit, and a differential amplifier circuit having inputs for receiving a first potential from a first junction formed between a pair of elements and a second potential from a second junction formed between paired elements for thereby generating a differential amplitude voltage signal indicative of the angle or strength of the magnetic field.

Abstract: An engine control apparatus for an internal combustion engine which is capable of performing engine cylinder identification economically, rapidly and easily with high accuracy, while capable of performing a backup control upon occurrence of abnormality. The control apparatus includes a first signal detector (81) provided in association with a crank shaft (11) for obtaining a first signal series, a second signal detector (82) provided in association with a cam shaft (1) for obtaining a second signal series (SGC) and a control means (100) for controlling parameter (P) involved in operation of the engine on the basis of each signal series. The first signal series includes an angular position signal and a reference position signal (.theta.R) for a specific cylinder group, while the second signal series includes cylinder identifying signal pulses. The pulse identifying a given cylinder differs from those for the other cylinders.

Abstract: A controller for a four-stroke cycle internal-combustion engine does not incur an operation failure in an engine even at the startup when injectors are placed under injection control at the same time and a cylinder group to be ignited is placed under ignition control at the same time.

Abstract: A cylinder identifying apparatus for an internal combustion engine including a rotary signal generator, a measuring device, a calculating device and an identifying device. The rotary signal generator generates, in synchronism with a rotation of the engine, a signal having first positional pulses, each corresponding to one of a plurality of cylinders of the engine, and a second positional pulse corresponding to a specific one of the cylinders. The measuring device measures the time periods between the beginning of each contiguous pulse, as well as the time periods representing the width of each of the pulses. The calculating device then calculates ratios of each of the time periods representing the widths of the pulses to their corresponding time period of the time periods representing the time between the beginning of each contiguous pulse. These ratios are then normalized.

Abstract: In a multi-cylinder internal combustion engine, an ignition control apparatus for suppressing generation of high-level noise and voltage leakage due to unwanted increases; in spark plug demand voltage. The apparatus includes (i) an angular position signal generator for generating a predetermined angular position signal for each of the cylinders in dependence on the rotation speed of the engine, (ii) sensors for detecting relevant operation states of the engine, (iii) fuel injectors for injecting fuel into the cylinders, (iv) an ignition system for firing a fuel mixture within each of the cylinders, and (v) a controller for generating a fuel injection signal for the fuel injectors and an ignition timing signal for the ignition system. These two signals generated by the controller are generated on the basis of the angular position signal and the engine operation state signal.