Mitsubishi Denki Kabushiki Kaisha

Shingo Morita

Mitsuru Koiwa

Wataru Fukui

Yutaka Ohashi

Shuichi Wada

Takafumi Narishige

Shigemi Murata

Koichi Okamura

Kazuya Hamada

Mituru Koiwa

To provide a high tension connection portion structure for an ignition device for an internal combustion engine, which may prevent an instantaneous breakdown of the connection even if an external force is applied to a high tension connection portion, may enhance a connection property of the high tension connection portion by suppressing a sliding movement between metal terminals of the connection portion and may be applied to the path of a minute current such as an ionic current or the like, a connecting structure of a high tension connection portion used in an ignition device for an internal combustion engine, includes: a first high tension connection terminal ; a second high tension connection terminal for electrically connecting with the first high tension connection terminal ; a locking mechanism provided between the first high tension connection terminal and the second high tension connection terminal for restricting the separation therebetween in the axial direction; and a spring member disposed between the first high tension connection terminal and the second high tension connection terminal

High tension connection portion structure of an ingition device for an internal combustion engine

Ignition coil apparatus for an internal combustion engine and production method thereof

A combustion state detecting device for an internal combustion engine enables diverse combustion state detection by obtaining a plurality of currents analogous to an ion current. The combustion state detecting device includes a bias circuit,that applies an ion current detection voltage to an ignition plug,disposed in a cylinder of the internal combustion engine, an ion current signal distributor circuit,made up of a current mirror circuit for detecting the ion current on the basis of a voltage from the bias circuit, and current-voltage converter circuits,and,, to thereby produce a plurality of currents analogous to the ion current by the ion current signal distributor circuit.

Combustion state detecting device for an internal combustion engine

An combustion state detecting apparatus for an internal-combustion engine is equipped with: an ignition coil (4) for applying a high voltage (V2) for igniting to the spark plugs (8a through 8d) of the cylinders of an internal-combustion engine; an ionic current detecting circuit for applying a bias voltage (VBi) to at least one spark plug to detect ionic currents (ia, ib) flowing via the spark plug which has just been subjected to ignition control; comparator circuits (14a, 14b) which compare detected ionic current signals (Eia, Eib) with threshold values (TH1, TH2) and turn them into ionic current pulses (Gia, Gib); and an ECU (2A) which drives the ignition coil according to a crank angle signal (SGT) and determines the combustion state of the internal-combustion engine. The ECU changes the threshold values for each ignition control and judges the combustion state according to the respective threshold values and the state in which the ionic current pulses are generated.

Combustion state detecting apparatus for an internal-combustion engine

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. The engine cylinders belonging to each cylinder group are so selected as not to be controlled in succession for ignition. In making misfire decision, the electronic control unit (2) makes use of the ion current detection signal derived from the ion current detection circuit means provided in association with the cylinder group which includes the engine cylinder currently subjected to the ignition control.

Misfire detecting apparatus for internal combustion engine

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. A knock controller decides the amount of delay based on the count value of the pulses.

Knock control system for an internal combustion engine

Disclosed is an ignition apparatus for an internal combustion engine including a power switch 20 for intermittently feeding a primary current to an ignition coil, a primary coil 5 and a secondary coil 6 of the ignition coil being contained in an insulation case 1 with the power switch 20, primary coil 5 and secondary coil 6 being fixed by an insulating resin material 15 poured into the insulation case 1, the ignition apparatus comprising a shield plate 23 interposed between the secondary coil 6 and the power switch 20 to shield the power switch 20 from electromagnetic waves. With this arrangement, there can be obtained an ignition apparatus for an internal combustion engine by which the malfunction of the power switch and the like caused by electromagnetic waves generated at the ignition coil can be prevented.

Ignition apparatus for internal combustion engine

An ignition coil for an internal combustion engine to suppress the superposition of a noise signal caused by a capacitive discharge current at an ignition plug to thereby prevent the faulty operation of other circuit devices. The ignition coil has first and second non-magnetic bobbins into which a magnetic core 3 is inserted, a primary coil (1) wire wound around the first bobbin, a secondary coil (2) wire wound around the second bobbin, an interrupting circuit 7 connected to one end of the primary coil for interrupting a primary current i1 flowing to the primary coil, and an ignition plug 5 connected to one end of the secondary coil for generating a discharge spark by a secondary voltage V2 output from the secondary coil. A buffer coil 8 having an inductance which is much smaller than that of the primary or secondary coil is connected in series with one of them.

Ignition coil for internal combustion engine

An ignition coil has an inorganic insulator material featuring a larger conductivity in the direction along the surface of the material than in the direction perpendicular to the surface of the material, between high-tension voltage components internal to a casing and conducting components internal and external to the casing. Localized discharge deterioration advancing from the high-tension components toward the conducting components is changed in its direction of advance to the direction along the surface of the inorganic insulator material, and is diffused accordingly. The resistance of the ignition coil against localized discharge deterioration is increased, and improved reliability in breakdown performance is resulted. This leads to a compact design. The casing and bobbins are constructed of mica sheet as inorganic insulator material using insert molding technique, and productivity of the ignition coil is improved.

Ignition coil including inorganic insulator exhibiting higher

A capacitor discharge ignition device for an internal combustion engine includes a booster coil 21 and a transistor 22 for generating a boosted voltage; a circuit 15A for generating a switching signal for the transistor in response to an ignition signal; first and second condensers 7, 8 for charging with the boosted voltage; an ignition coil 10 to whose secondary a spark plug is connected; a thyristor 13 forming a first closed discharge circuit with the first condenser and the ignition coil primary, which is turned on in synchronism with the ignition signal; and an inductor 9 forming a second closed circuit with the second condenser, the ignition coil primary and the thyristor. The discharge energy of the second condenser stored in the inductor is supplied to the ignition coil primary to extend the discharge time at the spark plug. A delay circuit 16 prevents the transistor from turning on during the extended discharge time, thus establishing a third closed inductor discharge path through the booster coil.

Capacitor discharge ignition system with inductively extended discharge

An LCDI-type ignition apparatus for an internal combustion engine includes first and second capacitors connected to an ignition coil and a voltage source for generating a charging voltage for the capacitors. The first capacitor is for producing an initial discharge of a spark plug, and the second capacitor is for lengthening the discharge of the spark plug after discharge has been initiated by the first capacitor. In one form of the invention, the second capacitor is charged only after the first capacitor has been charged by the voltage source to a prescribed voltage sufficient to produce a suitable discharge of the spark plug. As a result, even when the engine is operating at a high rotational speed and the time between consecutive firings of the engine is small, an adequate ignition voltage can be obtained. In another form of the invention, the charging voltage(s) of one or both of the capacitors is or are varied in accordance with the one or more engine operating conditions. Each charging voltage can be controlled to the minimum necessary value based on the present engine operating conditions.

Ignition apparatus for an internal combustion engine

An ignition device for an internal combustion engine including: a DC power source; a convertor for raising the voltage of the DC power source to a predetermined voltage; a charge storing device arranged to be charged with the output from the convertor; an ignition coil; an ignition signal generator for generating an ignition signal in synchronization with the rotation of the internal combustion engine; a switch which is switched on in response to the ignition signal generated by the ignition signal generator to discharge a charge stored in the charge storing device through the ignition coil; and a controller for stopping the operation of the convertor during a period in which the ignition signal is being transmitted from the ignition signal generator.

Ignition device for internal combustion engine

An ignition apparatus for an internal combustion engine is able to reduce generation of noise and energy loss due to wiring to a substantial extent. A capacitor 4 is connected at one end thereof to a DC power supply so as to be charged thereby, and at the other end thereof to an ignition coil 5. A switching element 9 is connected between the capacitor and a primary winding of the ignition coil to form part of a discharge path through which the capacitor discharges. The switching element is made conductive by means of an ignition or trigger signal which is generated by a signal generator in synchronism with the rotation of the engine, so that the charged capacitor discharges through the primary winding of the ignition coil. The capacitor, the ignition coil and the switching element are formed integrally with each other, housed in a single casing 13 and connected to each other without the use of a wire harness.

A capacitor discharging type ignition apparatus for an internal combustion engine is disclosed in which a secondary winding voltage rises quickly and has an extended spark generation time as well. The apparatus includes an electrical power source 101, an ignition coil 104 having a primary winding and a secondary winding connected to a spark plug, the primary winding having a first end terminal, a second end terminal and a third intermediate terminal between the first and second end terminals, a first capacitor 103a connected between the electrical power source and one of the first and second end terminals of the primary winding so that it is charged by the electrical power source; a second capacitor 103b connected between the electrical power source and the intermediate terminal of the primary winding so that it is charged by the electrical power source; a signal generator 105 for generating an ignition signal in synchronism with the rotation of the engine; and a switch 107 for causing the first and second capacitors to simultaneously discharge through the primary winding in response to the ignition signal of the signal generator.

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Tokyo, Japan

Shingo Morita