Abstract: An ignition system for an internal combustion engine includes an ignition coil, electric power supply circuit, a switching transistor, engine condition detecting element or unit that detects a signal relating to flow speed of air-fuel-mixture gas in the engine, and ignition control unit that controls the switching transistor to provide multiple ignition sparks in a predetermined ignition period. The ignition control unit controls the switching transistor to maintain each of the ignition sparks according to the signal relating to the flow speed of air-fuel-mixture gas in the engine to maintain sufficient spark energy for igniting the air-fuel mixture gas.

Abstract: An ignition system for an internal combustion engine includes an ignition coil, electric power supply circuit, a switching transistor, engine condition detecting element or unit that detects a signal relating to flow speed of air-fuel-mixture gas in the engine, and ignition control unit that controls the switching transistor to provide multiple ignition sparks in a predetermined ignition period. The ignition control unit controls the switching transistor to maintain each of the ignition sparks according to the signal relating to the flow speed of air-fuel-mixture gas in the engine to maintain sufficient spark energy for igniting the air-fuel mixture gas.

Abstract: A vector processing device includes a vector unit having operation pipelines and a vector register connected to the operation pipelines, a memory unit to be operated by the operation pipelines and results of operations obtained from the operation pipelines, and a memory control unit having a data buffer provided between the vector register and the memory unit. The vector processing device also includes data buffer valid counter counting the number of pieces of data read from the vector register and sent to the data buffer, and pipeline stop predictor selectively interrupting outputting an access request from the vector unit to the memory unit on the basis of the number of pieces of data counted by the data buffer valid counter when the operation pipelines are chained via the vector register.

Abstract: A vector processing unit includes a vector unit having a plurality of operation pipelines and a vector register connected to the plurality of operation pipelines, a scalar unit having a buffer, and a memory unit. A memory unit controller, which is connected between the memory unit and the vector unit and between the memory unit and the scalar unit, performs an information transfer in accordance with a serializing process among access requests by using a post instruction and a wait instruction. The access requests sandwiched between the post instruction and the wait instruction are serially carried out whereby the memory unit is serially accessed. A first unit assigns a post mark to each of access requests of vector store instructions that are issued during a time when the post instruction is being executed, and stops instruction execution of the scalar unit when there is a vector store instruction proceeding to the post instruction.

Abstract: A gas/liquid separator device includes a separator, such as a cyclone type separator, provided in a blowby gas passage for introducing a blowby gas from a blowby gas chamber of an internal combustion engine, an oil accumulator in the form of a container for accumulating separated and condensed oil mist, another passage provided separately from the blowby gas passage for returning the oil from the oil accumulator to an oil collection chamber, and a communication blocking element for blocking a communication between the oil accumulator and the oil collection chamber while the engine is running.

Abstract: A fuel injection pump including a valve opening and closing an overflow passage formed in a body of the pump to connect a high pressure chamber to a low pressure chamber. The low pressure chamber is provided for reserving low pressure fuel, and the high pressure chamber is provided for pressurizing fuel sent from the low pressure chamber and for discharging the pressurized fuel to fuel injectors. A plunger has intake grooves which open the feed passage to communicate the high pressure chamber with the low pressure chamber on an intake action of the pump. The body of the pump has a feed passage formed therein which connects the high pressure chamber to a control chamber. The pressure in the control chamber is changed by the expansion and contaction of a piezoelectric actuator, and the pressure in the control chamber urges the valve in a direction in which the valve closes the overflow passage.

Abstract: A fuel injection system in which a fuel injector having a fuel pressure control chamber formed therein to create a pressure which forces a needle valve in the closing direction to open and close the nozzle hole, an accumulator to retain fuel discharged from the nozzle hole, and a fuel injector provided at each of the cylinders of the engine, are connected to the fuel injection pump by a single piping system without utilizing a special distribution mechanism. The volume of the fuel pressure control chamber in the fuel injector can be changed by a piezo-actuator. A check valve is provided at a half way point of the piping which leads the fuel fed under pressure from the fuel injection pump to the fuel injector into the fuel pressure control chamber and the accumulator, so that the fuel is fed through the check valve into the fuel pressure control chamber and the accumulator.

Abstract: A pump including a plunger slidably disposed in a pump body, a transmitting member connected to the plunger, a coil spring which urges the plunger, and a cam urging the plunger against the coil spring. The plunger defines a pump chamber in the pump body. The coil spring urges the plunger in a direction such that the plunger contracts the pump chamber. The cam rotates in synchronization with the rotation of the engine and engages with the transmitting member for part of the cycle of the rotation of the engine so that the plunger increases the volume of the pump chamber. The cam releases the plunger in the remaining cycle of the rotation of the engine to allow the coil spring to urge the plunger so that the plunger displaces in a direction to reduce the volume of the pump chamber.

Abstract: A spark-ignition type internal combustion engine has a fuel injection valve for supplying fuel directly to a cylinder and a spark plug arranged near the fuel injection valve for igniting fuel in the cylinder. Auxiliary fuel injection is performed in the vicinity of the top dead center of the compression stroke, the subsequent main fuel injection is performed after the auxiliary fuel injection is terminated, and concurrently, the spray produced by auxiliary fuel injection is ignited by the spark plug.

Abstract: Disclosed is a piezoelectric control valve which is arranged midway in a passage for supplying a high-pressure fuel to a fuel injection valve, and opens and closes this passage according to expansion and contraction of a piezoelectric element laminate. The valve body of the piezoelectric control valve is slidably held in a bore into which a high-pressure fuel passage connected to the fuel injection valve and a low-pressure fuel passage communicating with a fuel storage portion are opened. An annular groove is formed on the peripheral surface of the valve body, and the high-pressure fuel passage and the low-pressure fuel passage can communicate with each other through this annular groove. A piston moving reciprocatively according to expansion and contraction of the piezoelectric element laminate is provided, and a pressure chamber is formed between the piston and the valve body.

Abstract: An electronically controllable, ultra-high pressure fuel injector comprises a differential pressure type injection nozzle which is opened and closed by an actuating element operated by a hydraulic power cylinder including a piston received in a working chamber. Working fuel to the working chamber of the power cylinder is ON/OFF controlled by an electronically controllable solenoid valve which when energized releases the pressure in the working chamber to open the injection nozzle. In order to ensure that the power cylinder is controlled by a compact, high response solenoid valve, the construction of the power cylinder and the injection nozzle is such that the force applied to the power cylinder piston by the working fuel pressure in the working chamber is substantially greater than the force applied to the actuating element by the fuel pressure in the pressure chamber in the injection nozzle or the fuel pressure in the passage for supplying the working fuel.

Abstract: A system for control of the amount of fuel to be injected in an internal combustion engine uses a high-pressure pump and a fuel control valve mechanism for spill having an electromagnetic valve and an oil-pressure valve. A predetermined delay time is added to the control timing of the current supply to the fuel control valve mechanism for spill, thus achieving the injection of the required amount of fuel at the most appropriate timing.

Abstract: A fuel injector for an internal combustion engine, the injector being actuated by a piezoelectric actuator. The piezoelectric actuator operates a piston, which changes the volume of a pump chamber formed between the piston and a nozzle needle. The nozzle needle moves up and down in response to a pressure in the pump chamber to open and close a port for injecting fuel. The piston is pressed toward the pump chamber by a fluidic force or a spring force and so on.

Abstract: A hydraulic control valve having a piezoelectric actuator comprises an expansible sleeve loosely received within a bore of the valve housing, with one end thereof being fixedly or stationarily mounted relative to the housing and the other end thereof being expansibly mounted within the bore. A slidable first piston is mounted within the bore of the valve housing and is urged against the other end of the expansible sleeve. This first piston floatingly supports one end of the piezoelectric actuator, the other end of which is supported by a second piston which is slidably mounted within the sleeve and is coupled to a valve member operable to cooperate with a valve seat to open and close an inside fuel passage communicating an inlet port with an outlet port.

Abstract: A multi-gap spark ignition system is disclosed. The system comprises a plurality of spark gaps which are formed in series. The length of the spark gaps increases from the high voltage power source side towards the earth side. According to the present invention, necessary voltage to be applied to the spark ignition system can be decreased.

Abstract: A piezo-type valve with piezo-elements as a valve actuator. The piezo-elements are interposed by two freely movable pistons. A pressure chamber is formed on the outer side of one of the pistons to limit its outward movement. Thus, the substantial part of the expansion of the piezo-elements is transmitted to the other piston. The other piston is connected to a valve element. At least one flow port and a relief port are formed in the valve body. When voltage is applied to the piezo-elements, the at least one flow port and the relief port are communicated.

Abstract: A spark plug for spark ignition type internal combustion engines includes an earth electrode formed of a heat-resisting metal, a central electrode, and a supplementary electrode provided on the earth electrode or the tip end of the central electrode. The supplementary electrode cooperates with one of the other electrodes to define therebetween a spark gap which is smaller in dimension than the normal spark gap defined between the earth and central electrodes. The supplementary electrode has a higher specific resistance than that of the earth electrode.

Abstract: A flow control device advantageously used in a fuel injection system for a diesel engine. The flow control device includes a spool valve defining on its sides first and second chambers which are connected with each other by means of a throttle. The second chamber is connected to a high pressure pipeline connecting a fuel pump with a fuel injector, while the first chamber is selectively opened to a relief line by means of an electrically operated valve. A cylinder has an annular groove opened to the relief line. When the valve is opened, the first chamber is opened to the relief line. A pressure difference is thus created between the first and the second chambers so as to move the spool valve to open. Thus fuel injection is stopped.

Abstract: A multi-gap spark ignition device to be installed in a spark ignition engine, is disclosed. The device comprises a metallic base member provided with a hole which forms one portion of the combustion chamber of the engine. Within the wall defining the hole, a high voltage electrode, a plurality of intermediate electrodes and an earth electrode are embedded at regular intervals so that each end of the electrodes project into the hole to form a plurality of spark gaps between the adjacent ends of the electrodes. Each of the intermediate electrodes is composed of an electrode member and an insulating member for covering one end of the electrode member, and is closely inserted into a groove formed in one end surface of the base member along the hole thereof at regular intervals.

Abstract: In an ignition system for an internal combustion engine in which the flow of a primary winding energizing current is switched on and off in synchronism with the rotation of the engine and a high voltage is induced in the secondary winding upon switching off of the energizing current, an energizing current is supplied again at around the top dead center of each cylinder and then decreased gradually and interrupted in accordance with a sawtooth waveform whose voltage attains a predetermined potential at around the top dead center and then decreases gradually.