Abstract: A projection television apparatus which has three monochromatic cathode-ray tubes, two type of dichroic mirrors, and a lens. Red, green and blue images from the three tubes are combined into the color image by the two types of dichroic mirrors and the resulting image is enlarged and projected on the screen by one lens. The two types of dichroic mirrors are crossed at a right angle in the shape of an "X". Each type of dichroic mirror is split in two through the line of intersection and the two parts of the respective dichroic mirrors of each type have different transmission characteristics, so that color shading is improved.

Abstract: An engine system comprises an internal combustion engine and an exhaust gas treatment system, such as a three-way catalytic converter or an oxidation catalytic converter. The engine has an additional intake means, in addition to a main intake means for admitting by induction an air fuel mixture to a combustion chamber, for admitting under pressure above atmospheric pressure air to the combustion chambers during a period initiating during the exhaust stroke and terminating during the intake stroke for the purpose of expelling residual gas from the combustion chamber to bring about a stable combustion.

Abstract: An electronic controlled carburetor has an induction passage into which fuel is fed by a fuel metering system communicated with the atmosphere through main and auxiliary air bleed passages. The main and auxiliary air bleed passages have therein main and auxiliary solenoid valves, respectively, for altering the rate of air flow therethrough. A control circuit determines the duty ratio of a first pulse signal applied to the main solenoid valve in response to an air/fuel ratio indicative signal from an oxygen sensor. The control circuit determines the duty ratio of a second pulse signal applied to the auxiliary solenoid valve from the duty ratio of the first pulse signal so as to permit the main solenoid valve to operate around 50% duty ratio over all engine operating modes.

Abstract: An engine is provided with two spark plugs in each combustion chamber to ignite stoichiometric air-fuel mixture mixed with a large proportion of inert gases to lower NOx emission level. The engine is equipped with hydraulic valve lifters which are mechanically connected to intake and exhaust valves to control the valve overlap of the intake and exhaust valves. By the action of the valve lifters, the valve overlaps are increased in the normal driving operation range of the engine to prevent discharge at the terminal stage of exhaust valve opening exhaust gases containing a considerably large amount of hydrocarbons.

Abstract: A knocking discrimination apparatus in which an output signal derived from a knocking sensor is held at an almost constant level regardless of condition of an internal combustion engine by means of providing a control circuit therein for controlling the output signal of the knocking sensor to be held at the almost constant level, and further the above constantly held output signal of the knocking sensor and a constantly settled reference signal are compared with each other for discrimination of knocking, so that such a remarkable effect can be obtained that the reliability of the discrimination of knocking is improved exceedingly on account of a reliable reference signal for comparison ensured by being maintained at a constant level persistently and stably.

Abstract: A combustion chamber of an internal combustion engine has the form of a B-shaped chamber which consists of two spheroidal or spherical contiguous chambers which form an inwardly extending projection against which the air and fuel mixture impinges so as to be divided into two swirl flows which sweep residual burned gases of the previous cycle in the combustion chamber, thereby preventing knocking in the operation of the engine to improve the fuel consumption, driving performance and output of the engine.

Abstract: A control system for an internal combustion engine comprises a transducer for issuing a signal representative of combustion pressure in a combustion chamber, a unit consisting of a bandpass filter and a wave-form shaping circuit for issuing a signal representative of existing combustion timing of the combustion chamber by processing the signal from the transducer for detection of rapid increase of the combustion pressure; a reference timing circuit for issuing a signal representative of a predetermined reference combustion timing of the combustion chamber in accordance with operation modes of the engine, a comparator circuit for issuing a signal representative of a difference between the signal from the unit and the signal from the reference timing circuit, and a unit consisting of a discriminating circuit and an actuator driving circuit for controlling the ignition timing, the air-fuel ratio of air-fuel mixture and the amount of exhaust gas recirculated into the intake system of the engine, by processing the

Abstract: An engine system of the invention comprises an internal combustion engine; a carburetor; an exhaust gas recirculation system; an exhaust gas treatment device; and a source of secondary air, in which there is provided a fluid network which interconnects the source of secondary air, the engine exhaust system at a position upstream of the exhaust gas treatment device and the exhaust gas recirculation system at a position upstream of an exhaust gas recirculation valve and there is also provided an air injection control valve fluidly disposed in the fluid network intermediate the source of secondary air and the exhaust gas recirculation system. The air injection control valve is adapted to selectively permit and prevent the admission of air to the exhaust gas recirculation system.

Abstract: An EGR control system includes a plurality of ON-OFF air valves to control the amount of air admitted into a control passage extending from a source of constant vacuum to a control vacuum chamber upon which an EGR control valve is operated. The air valves are selectively energized by a controller containing a microcomputer wherein an exhaust gas control strategy is stored.

Abstract: A multi-cylinder internal combustion engine has siamesed exhaust ports each of which is shared by two adjacent cylinders. The valve timings of intake and exhaust valves of the two cylinders are so adjusted that flow of the exhaust gases from one cylinder is not obstructed in the siamesed exhaust port by the flow of the exhaust gases from the other cylinder in order to prevent power outputs of the two cylinders from being unbalanced.

Abstract: A spark plug is located in a combustion chamber so as to decrease the combustion time of the charge inducted into the combustion chamber. The charge is formed, before inducted into the combustion chamber, by mixing an air-fuel mixture and substantially inert gas such as exhaust gas so that the weight ratio of the fuel combusted in the combustion chamber and the substantially inert gas falls within the range from 1:13.5 to 1:18.5 during normal engine operation.

Abstract: A four-stroke reciprocatory internal combustion engine has a scavenging phase in which air is admitted under pressure into the cylinder and has a swirl generating phase in which a high-speed jet of air is admitted under pressure into the cylinder so as to swirl air fuel mixture charge in the cylinder around the cylinder axis. The engine has, in addition to an intake valve that controls induction of air fuel mixture into the cylinder, a separate air inlet valve which effects the scavenging phase and swirl generating phase.

Abstract: An internal combustion engine has at least one cylinder acting as an air pump for the admission of scavenging air into the remaining cylinders.

Abstract: An internal combustion engine of the reciprocating piston type, which is provided with an exhaust gas recirculation circuit to suppress the formation of NOx and has two or three spark plugs for each combustion chamber. There is a substantial overlap of the opening periods of exhaust and intake valves, so that a portion of the combustion gas is left unexhausted. The combustion chamber has a simple shape such as hemisphere, and the spark gaps of the plural spark plugs are arranged distant from each other in each combustion chamber so as to respectively share approximately equally divided portions of each combustion chamber. The number of the spark plugs is two when the volume of the recirculated exhaust gas, including the unexhausted combustion gas, is about 50% at the maximum of the volume of air admitted into the combustion chamber but three when the recirculated exhaust gas amounts to about 60% of the air at the maximum.

Abstract: A dual spark plug ignition engine is equipped with an EGR system. The two spark plugs in each combustion chamber are simultaneously energized to produce sparks to ignite the charge in the combustion chamber under a normal engine operating conditions, whereas the spark plugs are energized with a predetermined phase difference from each other under high power output engine operating conditions.

Abstract: A control system is adapted for an internal combustion engine in which a jet of air is injected into each combustion chamber via a second intake valve during each exhaust cycle and the subsequent intake cycle. The system comprises a source of compressed air having a pressure to be varied in accordance with the engine speed, an injection passageway leading from the source toward each second intake valve and a flow controller operated in accordance with changes in intake manifold vacuum. The flow controller includes a scheduled flow area therethrough to increase, under conditions in which the engine speed is constant, the amount of air passing through the injection passageway in accordance with increasing engine load in such a way as to increase the ratio of air flow through the injection passageway to the intake air flow to the engine under light engine load in order to cope with increasing residual gas fraction within each combustion chamber when the engine idles or operates under deceleration of the vehicle.

Abstract: Control system is adapted for an internal combustion engine in which a jet of air is injected into a combustion chamber via a second intake valve during a period overlapping an exhaust cycle and the subsequent intake cycle for expelling residual gas within the combustion chamber in order to reduce residual gas fraction of charge for the subsequent combustion within the combustion chamber. The system comprises a source of compressed air having a constant pressure, an injection passageway leading from the source toward the second intake valve, a flow control valve fluidly disposed in the injection passageway, and means whereby the flow control valve will vary effective flow area of the injection passageway in response to a signal indicative of the flow rate of fluid passing through the engine induction passageway.

Abstract: A valve operating mechanism comprising a valve, a cam, a cam shaft for rotating the cam about an axis, a rocker lever rotatably mounted about a rocker lever shaft. The rocker lever is axially movable along the rocker lever shaft. The cam is tapered in the longitudinal direction of the axis and has a uniform cross sectional shape. The rocker lever has an arm formed with a surface engaging the cam and an opposite arm provided with means for engaging the end of a valve stem of the valve.

Abstract: Hemispherical combustion chambers of a cross flow type cylinder head, having symmetrically disposed and synchronously sparked plugs are fed a near stoichiometric air fuel mixture containing up to 40% EGR gas which after combustion is exhausted through individual ports, mixed with secondary air supplied by a simple reed valve and oxidized in a catalytic converter.

Abstract: Disclosed herein is an engine system which comprises an internal combustion engine, an air admission system to admit scavenging air, under pressure, into an engine cylinder through an additional intake valve and an EGR system. The air admission system includes an air pump and an EGR conduit of the EGR system having an inlet end connected to the engine exhaust conduit and an outlet end connected to the air admission system upstream of the air pump to effect admission of recirculated exhaust gas through the additional intake valve together with scavenging air. With this EGR system and the replacement of residual gas with scavenging air, the rate of exhaust gas in the engine cylinder upon ignition is kept substantially constant over varying partial loads.