Mitsubishi Denki Kabushiki Kaisha

Mitsubishi Denki K.k.

Masayuki Ikeuchi

Shigemi Murata

Toshio Iwata

Toshio Ohsawa

Toshiaki Hata

Kouichi Okamura

Wataru Fukui

Yutaka Ohashi

Izuru Shinjo

Atsushi Ueda

Koichi Okamura

Masami Matsumura

Shinichi Nobuto

Takanobu Yonetsu

An apparatus for detecting an angular position of a crankshaft of an internal combustion engine includes a disk which is rotatable in synchronism with the rotation of the crankshaft, a row of magnetic elements disposed on the disk along a circumferential periphery thereof at circumferentially equal intervals, an electromagnetic pick-up device disposed orthogonally to a plane of rotation of the disk in opposition to the row of magnetic elements, and a shaping circuit for shaping an output signal of the electromagnetic pick-up device into a rectangular waveform signal. The shaping circuit is combined integrally with the electromagnetic pick-up device into a single unit to prevent external noise from being superposed on the output signal from the pick-up device. The shaping circuit includes an integrator for integrating the output signal to produce a reference signal for the comparator. Additionally, the shaping circuit may include a rectifying/smoothing circuit for rectifying and smoothing the output signal of the pick-up device to produce a level signal, and a high-pass filter circuit having a cut-off frequency which is variable in dependence on a change in the level signal. The output signal of the pick-up device is input to the comparator after having passed through the high-pass filter circuitry so that a pulsating noise component superposed on the pick-up output signal and having a frequency corresponding to the engine rotation speed is satisfactorily eliminated. Thus, accuracy and reliability of the engine control can be remarkably improved.

Angular position detecting apparatus with noise discrimination

An ignition apparatus for an internal combustion engine includes a reduced number of component parts which can be arranged or laid out without difficulty within a limited space such as a vehicle engine room. The apparatus can be manufactured at low costs and it is also highly resistant to electrical noise from adjacent electrical and electronic elements and hence has improved reliability in operation. The apparatus includes an ignition coil connected to a spark plug which has electrodes present in a combustion chamber of a cylinder, a switch unit for controlling power supply to the ignition coil, and an ion current sensing unit connected to the spark plug for sensing an ion current generated between the electrodes of the spark plug during combustion of a mixture in the combustion chamber. The ignition coil and the switch unit, or the ion current sensing unit and the switch unit, or all of these elements, are integrally formed with each other to provide an integral assembly. In a preferred form, the switch unit and the ion current sensing unit comprise a hybrid integral circuit. The switch unit includes a switch in the form of a power transistor connected to the ignition coil, and a switch driver for driving the switch. The power transistor can be formed separately from the ion current sensing unit whereas the switch driver can be integrally formed with the ion current sensing unit.

Ignition apparatus for an internal combustion engine

A direct current power supply applies a positive voltage between the center electrode and the ground electrode of a spark plug in an internal combustion engine after discharge of the spark plug. Ionic current flowing between the electrodes due to the positive voltage is measured by a current sensor. The ionic current caused by the positive voltage is due to electrons, so it has a large magnitude and can be easily measured.

Ionic current sensing apparatus for engine spark plug with negative

An ignition system for internal combustion engines has an ignition coil having a primary winding and a secondary winding. The secondary winding supplies a high voltage for ignition to an ignition plug when the ignition coil is energized at the primary winding at a predetermined period. A voltage producing circuit produces a voltage on the basis of a signal developed across the primary winding when the primary winding is energized at a predetermined period. The voltage causes discharge across the electrodes of the ignition plug to form a path for an ion current developed in the cylinder. A comparator or detector detects the ion current to determine the combustion in a cylinder.

Ignition system for internal combustion engines

A capacitor is connected to an ignition coil for an internal combustion engine so as to be charged by ignition current generated by the ignition coil. After firing of a spark plug in a cylinder by the ignition current, the voltage across the capacitor is applied between the center electrode and the ground electrode of the spark plug to induce an ionic current between the electrodes. The resulting ionic current is measured by a current sensor connected to the capacitor.

Ionic current sensing apparatus

An angle detecting device including a magnetism gap where a magnetic-flux shutter rotates synchronously with a detection subject, a magnetic flux generator provided at one side of the gap, a magnetic-flux detector provided at the other side of the gap, an outlet of the signals from the detector, a frame integrally including the above-described generator, detector and outlet, and anchoring portions mechanically fixing the detector in a housing portion of the frame. In one embodiment, the anchoring portions are a pair of saw-toothed tabs formed by cutting and bending out a section of the plate. The saw-toothed tabs cut into the inner wall of the housing when the detector is inserted. In another embodiment, the anchoring portions are a pair of supporting tabs formed by bending extensions of the plate. The supporting tabs are clamped between a lower surface of the housing and a cover. In still another embodiment, a pair of coupling tabs provided with holes are formed integrally on the plate, and a pair of projections are integrally resin-molded in the housing portion of the frame. The projections passed through the holes are caulked when the detector is inserted.

Angle detecting device having improved mounting arrangement for mounting

An ignition apparatus for an internal combustion engine is provided in which malfunctions due to noise induced by a high ignition voltage can be avoided in a reliable manner. A controller controls the ignition timing of a cylinder of the engine in synchronism woth the rotation thereof. A detector 7-13 detects an ion current which is generated between the electrodes of the spark plug upon combustion of an air/fuel mixture in the cylinder. A filter 21 is connected to an input side of the detector for filtering noise contained in the ion current, the noise being induced by the ignition coil upon sparking of the spark plug. The ignition coil has a primary winding connected to the controller and a secondary winding connected to the spark plug. The filter is connected between the detector and a node P2 between the secondary winding of the ignition coil and the spark plug.

Ignition apparatus for an internal combustion engine with engine

A cylinder identification apparatus for a multi-cylinder internal combustion engine. The apparatus includes the following units. A reference signal generator that senses the rotation of an engine crankshaft and generates a reference signal indicating each time the crankshaft is at a prescribed rotational angle. An identification signal generator senses the rotation of the engine camshaft or other member coupled to and rotating at 1/2 the speed of the crankshaft and generates a cylinder identification signal having a different form for different cylinders of the engine. A control unit identifies each cylinder of the engine based on the form of the cylinder identification signal.

Cylinder identification apparatus

An ignition plug for an internal combustion engine includes an ionization current detector electrode 20 adapted to be coupled to an external ionization detector circuit. Preferably, the ionization current detector electrode extends through a lateral through-hole formed vertically through an expanded portion of the electrical insulator 3. The lower end of the ionization current detector electrode may extend into the combustion chamber by a predetermined length. Further, the lower end of the ionization current detector electrode exposed to the fuel/air mixture within the combustion chamber may form a cylindrical grid to increase the contact area with the combustion gas.

Ignition plug for an internal combustion engine provided with an

An ion current sensing device for an internal combustion engine is able to accurately sense an ion current generated between electrodes of a spark plug during combustion of a mixture even when the electrodes have been smeared by carbon or other combustion products deposited or accumulated thereon. A power source 14 supplies a bias voltage to the electrodes of the spark plug. An ion current sensing resistor 15 is connected between the elecrodes of the spark plug and the power source for sensing an ion current as generated between the electrodes of the spark plug each time a mixture in the combustion chamber is combusted. A comparator 11 compares the voltage across the ion current sensing resistor with a reference voltage and generates an output signal when the voltage is higher than the reference voltage. A filter comprising a capacitor 22 and a resistor 23 is connected between the ion current sensing resistor and the comparator for passing only AC components of the voltage across the ion current sensing resistor to the comparator while blocking a DC component thereof.

Ion current sensing device for an internal combustion engine with

An ignition apparatus for an internal combustion engine can prevent malfunctions due to noise induced by a high ignition voltage which is developed by an ignition coil upon ignition. Generation of a misfiring detection signal can also be prevented during fuel supply cut-off operations. To these ends, in one aspect, and ignition apparatus includes: a controller for controlling the ignition of a cylinder of the engine in synchronism with the rotation thereof; a detector connected to a spark plug and an ignition coil for detecting an ion current which is generated between the electrodes of the spark plug upon combustion of an air/fuel mixture in the cylinder; and mask a for masking the output signal of the detector in response to discharge of the spark plug. In another aspect, an ignition apparatus includes: a controller for controlling the ignition of and the fuel supply to a cylinder of the engine in synchronism with the rotation thereof; a detector for detecting misfiring in the cylinder; and mask a for masking the output signal of the detector when the fuel supply to the cylinder is cut off.

An ignition apparatus for internal combustion engines of which configuration is simplified to reduce production cost and improve reliability of the apparatus. The present invention with the above object can be completed in three main embodiments. The ignition apparatus according to one embodiment of the present invention has a distributor cap. The distributor cap comprises an ignition coil; a central electrode connected to the ignition coil; a plurality of side electrodes each connected to an ignition plug of each cylinder of the engine and selectively connected to the central electrode; a plurality of diodes each connected to the plurality of side electrodes each; a terminal connected to the diodes for outputting ion detecting signals; and a resin portion for holding the central electrode, the plurality of side electrodes, the plurality of diodes, and the terminal. In the above embodiment, the ion current detecting diodes are built in the distributor cap to remove the diode assemblies each provided to each cylinder of the engine, resulting in the decreased number of parts for the apparatus.

Ignition apparatus for internal combustion engine

An angular position detector mounted within an engine ignition distributor for detecting an angular position of a rotary shaft. The detector comprises a detecting element disposed about the rotary shaft for generating a detection signal corresponding to an angular position of the rotary shaft and a processing circuit disposed around the rotary shaft for processing the detection signal from the detecting element. The detecting element and the processing circuit are connected by an electrical conductor member which is arranged at a position sufficiently remote from the rotary shaft for reducing an undesirable effect of a high voltage which may appear in the rotary shaft.

Angular position detector apparatus

A rotational angle detector provided in an engine ignition distributor. Light emitting and the light receiving sections are disposed in opposed positions on the two sides of a disk fixed to a rotary shaft, and a pair of slit plates are respectively disposed in front of the light emitting and the light receiving sections with the disk interposed between the slit plates. At least one of the slit plates is formed of an electroconductive material and is grounded.

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Himeji, Japan

Masayuki Ikeuchi