Nissan Motor Company Limited

Hitachi, Ltd.

Iwao Imai

Masazumi Sone

Hiroshi Endo

Yasuki Ishikawa

Hiromitsu Nagae

Hideo Kasuya

Yukitsugu Hirota

To reduce the breakdown potential magnitude between the output tip surface of an ignition distributor rotor output segment and each of the output terminals of the distributor cap, the rotor output segment is made of a low thermally conductive material 0.1 mm to 1.00 mm thick, and a layer of a silicone dielectric material such as a silicone plate, viz., a plate including at least a sheet of silicone varnish-containing glass cloth, is secured to at least a portion of at least one of the top and bottom surface areas of the rotor output segment.

Method of making radio frequency interference suppressing ignition

An N cylinder internal combustion engine plasma ignition system comprises a DC-DC converter for boosting low DC voltage to high DC voltage. Each of N ignition energy charging circuits includes a first capacitor connected between the DC-DC converter and ground via first and second diodes. The capacitor is charged by the DC-DC converter. Each of N reverse blocked thyristors connected to a junction of the first diode and first capacitor selectively grounds an electrode of the corresponding first capacitor to discharge ignition energy stored in the first capacitor. For each cylinder a transformer connected between the first capacitor and a spark plug boosts and feeds the discharged energy to the plug. One end of the transformer primary winding is grounded via a second capacitor to generate a damped oscillation when the corresponding thyristor grounds the first capacitor. An ignition trigger signal generator sequentially triggers the corresponding thyristor in a predetermined ignition order whenever the engine revolves through a predetermined angle and supplies a pulse to the DC-DC converter in synchronization with the ignition trigger signal. Derivation of the high DC voltage is halted for a period of time according to the pulsewidth. Each of N core-less inductors connected in series with the secondary winding of a transformer restricts an abrupt large current flow from the corresponding spark plug, to extend the discharge duration of each spark plug and ignite the air-fuel fixture stably without misfire.

Plasma ignition system for an internal combustion engine

An optical power supply switching apparatus by which a battery power can be connected to or disconnected from at least one electric appliance provided for an automotive vehicle without generating electromagnetic noise or electromagnetic interference between the electric appliance and other audio equipment. The optical power supply switching apparatus according to the present invention comprises at least one light-emitting element, one optical fiber, at least one photoelectric transducer, at least one semiconductor contactless switching element, and a plurality of optical directional-couplers and optical filters where necessary, in addition to a special low-impedance coaxial power distribution line.

Optical power supply switching apparatus

A device for preventing noise leakage externally from a digital electronic apparatus using a clock pulse generator, comprising: (a) a metal casing; (b) a printed circuit board housed within the metal casing into which the digital electronic apparatus is assembled having a plurality of land patterns formed thereon at the end of various signal lines of the digital electronic apparatus; (c) a connector attached at one end of the printed circuit board having a plurality of connector pins therewithin for connecting said land patterns with external various apparatus; (d) an insulative film positioned on one surface of the printed circuit board closely adjacent to the land patterns; (e) a conductive film coated on one surface of the insulative member and coupled electrically to the metal casing; and (f) a plurality of chip-type capacitors which bridges between the conductive film and plurality of land patterns for effecting noise filtering and a method of manufacturing the device described above comprising the steps of: (a) coating a solder-resisting film on the conductive film except a portion to which the chip-type capacitors are connected and a portion to which the metal casing is electrically connected; (b) electrically connecting the conductive film to the plurality of chip-type capacitors to the land patterns in a soldering with a solder bath; and (c) electrically connecting the conductive film to the metal casing.

Device for preventing noise leakage and manufacturing method of the

A plasma ignition system for an internal combustion engine which varies a discharge time of a plasma ignition energy charged capacitor according to the engine operating condition, e.g., the current engine speed. The plasma ignition system comprises: (a) a plurality of plasma ignition plugs, each provided within the corresponding engine cylinder; (b) a DC-DC converter which produces and outputs a high DC voltage; (c) a plurality of first capacitors each for charging and discharging the high DC voltage from the DC-DC converter; (d) a plurality of switching circuits each connected to the corresponding first capacitor for defining the discharge time interval of the corresponding first capacitor in response to a trigger signal inputted thereto at a predetermined ignition timing; (e) a trigger signal generator which generates and outputs the trigger signal to each corresponding switching circuit, the width of the trigger signal being varied so as to become narrower when the engine rotates at a speed higher than a predetermined value; and (f) a plurality of transformers each connected to the corresponding capacitor which receives the high DC voltage from the corresponding first capacitor through the corresponding switching circuit at the primary winding thereof and boosts the high oscillation voltage generated at the primary winding thereof according to the winding ratio between the secondary and primary windings thereof so as to apply the boosted voltage to the corresponding plasma ignition plug.

Plasma ignition system for internal combustion engine

A plasma ignition system for an engine having any number of engine cylinders, which comprises: (A) a plurality of plasma ignition plugs each mounted within a corresponding engine cylinder; (B) a first power supply unit for supplying a first electric power into each plasma ignition plug so as to generate a spark discharge within each plasma ignition plug; (C) a first switching circuit for sequentially connecting the first power supply unit to each plasma ignition plug according to a predetermined ignition order; (D) a second power supply unit for supplying a second electric power into each plasma ignition plug so as to generate a high-temperature plasma gas within each plasma ignition plug; and (E) a second switching circuit for sequentially connecting two of the plasma ignition plugs within the respective engine cylinders, one engine cylinder being at the start of an explosion stroke and the other engine cylinder being at almost end of an exhaust stroke, in a predetermined delay after the occurrence of the spark discharge at the corresponding plasma ignition plug when the engine speed is below a predetermined value, so that the number of high-voltage withstanding characteristic capacitors and switching elements (thyristors) of the switching circuits can be reduced half that of engine cylinders and the power consumption of these first and second power supply units can be saved remarkably particularly when the engine speed exceeds the predetermined value, e.g., 3000 r.p.m.

In an auxiliary ignition system for starting a diesel engine having a plurality of plasma spark plugs installed in corresponding combustion chambers facing fuel injection valves, starting time is reduced by applying high ignition energy to the plugs following predetermined time intervals after fuel injection to the corresponding engine cylinders.

Ignition system for starting a diesel engine

An ignition system for a multi-cylinder internal combustion engine having a spark plug within each engine cylinder, wherein a single DC-DC converter is provided and a high-voltage withstanding characteristic capacitor is provided for each spark plug. The capacitor charges to the high DC output voltage of the DC-DC converter and operatively supplies the high DC voltage via a boosting transformer into the corresponding spark plug at a predetermined ignition timing. The amount of the discharge energy being varied according to the pulse width of an input signal of each switching circuit which operates to supply the charged high DC voltage of the capacitor into the corresponding spark plug, the pulse width being varied according to various engine operating conditions.

Ignition system for a multi-cylinder internal combustion engine of a

A plasma ignition system for an internal combustion engine having a plasma ignition plug within each of the engine cylinders, which comprises: (a) a low DC voltage supply such as a vehicle battery; (b) a high surge voltage generator which generates and distributes a high surge voltage having a negative peak value of about minus 15 kilovolts into one of the plasma ignition plugs according to a predetermined ignition order so as to generate a spark discharge at the plasma ignition plug; (c) a DC-DC converter which boosts the low DC voltage sent from the low DC voltage supply to a high DC voltage; (d) a plurality of plasma ignition energy charging means each of which charges the high DC voltage supplied from the DC-DC converter; (e) a plurality of thyristors each for connecting the plasma ignition energy charging means to the corresponding plasma ignition energy charging means to the corresponding plasma ignition plug in response to a first trigger signal applied thereat; (f) a trigger signal generator which generates and outputs the first trigger signal into the gate terminal of one of the thyristors according to the predetermined ignition order so as to turn on said thyristor and a second trigger signal for halting the high DC voltage from outputting from the DC-DC converter; (g) a plurality of inductors for producing an oscillation on a basis of the high DC voltage outputted from the corresponding plasma ignition energy charging means; and (h) a high DC voltage charging and discharging means for extending the turn-on interval of one of the thyristors which is triggered by the first trigger signal from the trigger signal generator, whereby the plasma ignition always occurs without misfire.

Radio frequency interference suppressing ignition distributor rotor

An ignition distributor wherein either a rotor electrode or each of cap electrodes is made of semiconductive alumina ceramics. The semiconductive alumina ceramics contains from 10% to 40% by weight titania (TiO.sub.2).

Ignition distributor for internal combustion engine

A plasma ignition system for an internal combustion engine, which comprises: (a) a low DC voltage power supply; (b) a DC-DC converter which converts a low DC voltage from the low DC voltage supply to the corresponding AC voltage and inverts the AC voltage to a high DC voltage; (c) a plurality of plasma ignition plugs each located within one of the cylinders; (d) a plurality of first capacitors each for changing the high DC voltage received from the DC-DC converter; (e) a plurality of photosensitive switching elements each connected between each corresponding first capacitor and ground and which turns on to apply the plasma ignition energy charged within the corresponding first capacitor to the corresponding plasma ignition plug at a predetermined timing; (f) a plurality of voltage-boosting transformers each having a common terminal of primary and secondary windings connected to one terminal of each corresponding plasma ignition energy capacitor and another terminal of the primary winding connected to the corresponding plasma ignition plug for boosting the voltage across the corresponding first capacitor to a still higher voltage at the secondary winding thereof depending on the winding ratio therebetween; (g) a plurality of second capacitors connected between another terminal of the secondary winding of each voltage-boosting transformer and ground so as to form an oscillation circuit together with the primary winding of the corresponding transformer;

Plasma ignition system using photothyristors for internal combustion

An electronic system for controlling engine parameters or the like such as the amount of fuel supplied to the internal combustion engine of an automotive vehicle having a radio receiver, the control system having a plurality of digital processing units such as microcomputers, where each unit operates in synchronization with a clock pulse. There is provided a clock pulse generator for each digital processing unit, the frequency of which is selected so that the higher harmonics of one clock pulse has a frequency difference of 10 KHz or more from the higher harmonics of other clock pulses in a broadcast band, whereby interference which can disturb the reception of a broadcast signal is avoided.

Interference avoidance electronic system for an automotive vehicle

A plasma jet ignition plug comprises an electric insulator formed with a discharge cavity and a plurality of electrodes communicating with the discharge cavity to form, within the discharge cavity, a spark gap. The plurality of electrodes include a central electrode connected to a high voltage electric source and a low voltage electric source, and a peripheral electrode which is grounded. The peripheral electrode substantially closes the discharge cavity and is formed with a jet opening. At least that part of at least one of the plurality of electrodes which communicates with the discharge cavity is made of a material selected from a group consisting of ferrite, a nickel alloy containing at least one of silicon, aluminum and magnesium, and electrically conductive ceramic.

Plasma jet ignition plug with cavity in insulator discharge end

An apparatus for suppressing noise radiating from an ignition system for an internal combustion engine is disclosed. The ignition system comprises a distributor which uses an electrically conductive ceramic or a PTC (Positive Temperature Coefficient) thermistor as a material for a rotary electrode and/or stationary electrodes. At least a spark discharging portion of the rotary electrode and/or spark discharging portions of the stationary electrodes are formed from the electrically conductive ceramic which has a resistivity ranging from 10.sup.-6 to 10.sup.-2 ohm.multidot.cm or from the PTC thermistor. Cooperating with them are the high resistor spark plug and the high tension resistor cable. The high resistor spark plug herein disclosed uses an elongate monolithic resistor which has a length not shorter than 8 mm and preferrably has a length of 15 mm.

Growing community of inventors

Yokosuka, Japan

Iwao Imai