Abstract: A fuel injection apparatus for an internal combustion engine has at least one fuel injection valve. An annular or ring-shaped electrode is mounted near the fuel injection valve to encircle the injected fuel. A high voltage generator produces an electric field between the electrode and the fuel injection valve as well as a surrounding wall which are both connected to the ground. Electrified fuel particles are finely atomized and prevented from attaching onto the surrounding wall to improve the operation, starting characteristic, and transient response of the engine.

Abstract: An internal combustion engine with direct fuel injection is disclosed which comprises at least one combustion chamber fitted with a fuel injection valve. A charging electrode is disposed in the combustion chamber near the fuel injection valve and is supplied with a high DC voltage from a voltage source so as to charge the particles of fuel injected from the injection valve and thereby to disperse them.

Abstract: An exhaust gas recirculation system for an internal combustion engine includes an exhaust gas recirculation passage for communicating an exhaust port with an intake passage through a recirculation flow control valve. The recirculation system according to the invention comprises a timing valve in the recirculation passage adapted to open at specified moments for extracting exhaust gases containing highly concentrated hydrocarbons. According to the invention, moreover, the exhaust port is concentrically divided into a plurality of ports to extract exhaust gases having high concentrations of hydrocarbons from the outermost divided port adjacent to the inner peripheral walls of the exhaust port to recirculate them into intake mixtures, thereby reducing the concentrations of hydrocarbons and nitrogen oxides in exhaust gases and thus fuel consumption.

Abstract: Apparatus for controlling the rotational speed of an I.C. engine in an idling operation comprises a constant pressure valve, a solenoid valve, and a control signal generator. A constant vacuum pressure produced by the constant pressure valve is modified by atmospheric pressure by means of the solenoid valve which is actuated by a pulsating signal produced in the control signal generator. The pulse width of the pulsating signal is variable in accordance with a detected engine speed. The modified vacuum pressure is coupled to a chamber of a main valve of a conventional boost controlled deceleration device to control the amount of air-fuel mixture supplied to the intake manifold of the engine.

Abstract: To effect EGR in an internal combustion engine with the maintenance of adequate balance between the suppression of NO.sub.x formation and preservation of stable engine operation, the condition of combustion in the engine is taken as the basis of feedback control of the volume of recirculated exhaust gas so as to correct a deviation of the total amount of the recirculated exhaust gas and unexhausted combustion gas in the combustion chamber from a desired amount. The intensity of an ionic current produced upon combustion in each combustion chamber, the magnitude of mechanical vibration of the engine or the frequency of misfire in a combustion chamber is detected as an exact indication of the condition of combustion.

Abstract: A pulse generator of the corona discharge type for sensing engine crankshaft angle in an engine control system having a rotor with a plurality of pulse generating elements angularly spaced about the rotor axis. In order to generate as many pulses for each revolution of the rotor as desired to permit accurate measurement of the angular displacement of the rotor axis from a reference point, the rotor is constructed of a disc having a plurality of angularly equally spaced apart segmented regions to act as the pulse generating elements, and at least one electrode is stationarily mounted with respect to the disc to form an air gap to generate corona discharges thereacross in succession in cooperation with each one of the segmented regions upon rotation of the disc. An impedance element is provided to develop a voltage signal in response to the generation of the corona discharge.

Abstract: Mass flow measuring apparatus includes ionizing electrodes and an ion collecting electrode located downstream of the ionizing electrodes where the ionizing electrodes are biased with a high DC voltage produced in response to ignition pulses of an internal combustion engine. The high voltage is derived from a tap of the secondary winding of the ignition coil of the ignition circuit. The ions are allowed to migrate at the same speed with the mass fluid flow an are collected by the collecting electrode. The transit time of the ions over the distance between the ionizing electrodes and the collecting electrode is measured. The period of the high DC voltage applied across the ionizing electrodes may be controlled in accordance with the magnitude of the load of the engine and/or the transit time of the ions.

Abstract: To effect EGR in an internal combustion engine with the maintenance of adequate balance between the suppression of NO.sub.x formation and preservation of stable engine operation, the condition of combustion in the engine is taken as the basis of feedback control of the volume of recirculated exhaust gas so as to correct a deviation of the total amount of the recirculated exhaust gas and unexhausted combustion gas in the combustion chamber from a desired amount. The intensity of an ionic current produced upon combustion in each combustion chamber, the magnitude of mechanical vibration of the engine or the frequency of misfire in a combustion chamber is detected as an exact indication of the condition of combustion.

Abstract: A feedback control system for controlling the flow rate of a gas which is either drawn from or introduced into an exhaust passage of an internal combustion engine for the purpose of lessening pollutants in the exhaust gas. The control system is embodied either as an exhaust gas recirculation control system or a secondary air injection control system and in either case comprises an electrically operated flow control valve, a control circuit to provide a control signal to the control valve based on input signals representing the engine operating condition so as to establish an optimum flow rate, and an electrostatic type flow rate detector which has the ability of forming ions in the gas to provide a feedback signal on an electrical principle.

Abstract: A piston slidably received in a tubular housing is movable in response to the instantaneous flow of intake air to vary the number of small diameter tubes through which fuel can be jetted under the influence of a variable electrostatic force induced by the application of a variable high voltage across an electrode immersed in the fuel upstream of the nozzles and an electrode arranged about and spaced from the tubular housing.

Abstract: In mass flow rate measuring apparatus wherein the fluid is ionized at intervals at a predetermined point of the fluid passage, a voltage is sensed when the ionized flow mass is collected by an electrode located downstream from the ionization point. Electromagnetic radiation, generated in response to the generation of a strong electric field that ionizes the fluid, is prevented by means of a gate circuit from being sensed as a signal for triggering a time measuring device. The signal from the gate circuit is coupled to a voltage sensing circuit that detects a point near or at the peak value of successive voltage waveforms to signal the time measuring device as a point of ion collection.

Abstract: Flow rate in a fluid passage is measured by making corona discharge in a section of the fluid passage to cause partial ionization of the fluid and measuring a current produced in a DC circuit including a pair of electrodes disposed in the fluid passage downstream of the corona discharge section. Variations in the relationship between the measured current and the flow rate with difference in inherent conductivity among fluids are evadable by measuring a basic current through the DC circuit while the corona discharge is interrupted and regulating a voltage for either ionization or measurement based on the basic current.

Abstract: A fuel supply control system comprising an electrostatic apparatus which produces an electric field in a section of a fuel discharge passage to cause a variation in the fuel flow rate in this section, a flow rate detector to provide a feedback signal representing an actual fuel flow rate and an electronic controller which controls the strength and/or polarity of the electric field so as to cancel any deviation of the detected actual fuel flow rate from an optimum flow rate determined by sensing some variables related to the operating condition of the engine.

Abstract: An engine having an even number of cylinders is caused to produce two differently composed exhaust gases, one rich in air and the other in unburned fuel and CO, from the two groups of cylinders each consisting of half the number of cylinders being fired in succession, which exhaust gases are fed separately to a thermal reactor and allowed to gradually mix with each other for mild and slow reaction therein.

Abstract: A flow rate detector of the type comprising a corona discharge circuit to cause partial ionization of a fluid at a section of a fluid passage and a probe positioned downstream for detecting the amount of ions carried by the fluid as an indication of the fluid flow velocity. To achieve direct detection of mass flow rate even when the fluid exhibits fluctuation in its density, the detector includes a control circuit which serves the function of maintaining the intensity of a discharge current flowing through the corona discharge circuit constant.

Abstract: A temperature sensor is disposed at the upstream or middle portion of a reactor for oxidizing the unburned constituents contained in the exhaust gases discharged from the combustion chambers of the engine. The air-fuel ratio of the air-fuel mixture supplied to the combustion chambers is controlled so as to maintain the temperature of the upstream or middle portion of the reactor at the predetermined level in the vicinity of but higher than the temperature corresponding to the critical point where the temperature of the downstream portion of the reactor begins to decrease.

Abstract: Under normal running condition of an internal combustion engine with a thermal reactor, the engine is fed with a relatively rich air-fuel mixture for regulating the concentration of unburned combustible compounds, such as hydrocarbons (HC) and carbon monoxide (CO) in the exhaust gases emitted therefrom, in a manner that the thermal reactor effectively functions, and under high speed heavy load condition of the engine wherein the exhaust gas temperature becomes remarkably high, the engine is alternately fed with a relatively rich mixture and a relatively lean mixture in accordance with the operating cycles of the engine for not only achieving the improved fuel economy but also protecting the thermal reactor from heat damage.

Abstract: An exhaust gas reburning device comprises a first reaction chamber receiving only rich HC and CO containing engine exhaust gases resulting from combustion of a rich air-fuel mixture having an air-fuel ratio lower than a stoichiometric air-fuel ratio to cause effective oxidation of rich HC and CO in the engine exhaust gases and a second reaction chamber separated from the first reaction chamber and receiving the resultant engine exhaust gases from the first reaction chamber and poor HC and CO containing engine exhaust gases resulting from combustion of a lean air-fuel mixture having an air-fuel ratio higher than the stoichiometric air-fuel ratio to effect sufficient oxidation of lean HC and CO in the engine exhaust gases of the lean air-fuel mixture and the remaining HC and CO in the resultant engine exhaust gases from the first reaction chamber by heat of the resultant exhaust gases and oxygen in the lean HC and CO engine exhaust gases.