A spark plug for an automotive internal combustion engine providing improved ignition even when carbon is deposited on the insulator of the plug. A rich fuel-air ratio causes carbon to be deposited on spark plug insulators, thereby decreasing its effective insulation. By limiting the geometrical dimension of the plug's center electrode, ground electrode, and insulator the problem of carbon build-up is overcome. The sizes of these elements have certain allowable ranges that enhance the igniting effect of the plug.

Spark plug for internal combustion engine

A fuel-injection pump, especially a direct fuel injection in spark-ignition internal-combustion engines, with at least one pump for generating a fuel flow under pressure and with a rotary slide valve moved synchronously with the drive shaft of the internal-combustion engine and intended for assigning the fuel flow to at least one injection port of the internal-combustion engine and/or for branching off the fuel flow under pump pressure into a return line, the rotary slide valve is mounted so as to be displaceable to a limited extent in the direction of its axis of rotation and/or so as to be rotatable to a limited extent in relation to the rotary drive of the rotary slide valve. Preferably, at the same time, the rotary position or displacement position of the rotary slide valve can be determined in dependence on an operating parameter of the internal-combustion engine, with the result that the axial displacement of the rotary slide valve counteracts a seizure of the rotary slide valve in its guide and determination in dependence on operating parameters affords the possibility of adjusting the injection time over a larger angular sector than would be possible in view of the geometrical limits placed on the design of the rotary slide valve.

Fuel injection pump for internal-combustion engines

A fuel injection system for an internal combustion engine including a fuel injector which can be subjected to fuel at high pressure and is actuatable via a metering valve device by which the pressure in a pressure booster control chamber is controllable such that the pressure in a pressure booster pressure chamber, defined by a pressure booster piston, that can be filled with fuel from the high-pressure fuel source via a filling path in which a check valve is disposed and that is in communication with an injection valve member pressure chamber, is increased by the pressure booster piston such that an injection valve member opens for injecting fuel, whereupon fuel is positively displaced out of a damping chamber via a damping path, in which a damping throttle is disposed. To assure stable injection performance, the damping path is embodied such and connected in such a way to the filling path that the fuel positively displaced from the damping chamber via the damping throttle in an injection event reaches the filling path of the pressure booster pressure chamber via the damping path.

Fuel injection system

Fuel is pumped and supplied to an injector which injects the fuel in the form of mist The quantity of fuel injected from the nozzle is regulated by quantity control means The control means is comprised of a control valve, which is disposed on the injection hole of the injector for controlling the area of the injection hole When the control valve has sufficient stroke to close the injection hole, the valve serves not only as a control valve, but also as a timing control valve The movement or stroke of the control valve is accomplished by an actuator which is controlled by electrical control means, for example a microcomputer, to enable a precise injection of fuel and an ideal combustion

Fuel injection apparatus

A variable-discharge high pressure pump (10) for pressure-feeding fuel to a common rail (6) for use in a diesel engine (1). The pump has a plunger (18), a plunger chamber (19), a cam (17) for reciprocatively moving the plunger; an opening-out type electromagnetic valve (15) capable of opening and closing one end of the plunger chamber, a fuel reservoir (22), a check valve (23) communicating with the plunger chamber, and an inlet pipe (14) for supplying fuel to the fuel reservoir. Both the introduction of the fuel into the plunger chamber and the return of the fuel from the plunger chamber to the fuel reservoir are effected through the electromagnetic valve.

Variable-discharge high pressure pump

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. Preferably, the fuel injector is provided with an injection rate control arrangement such as a flow control arrangement for limiting the flow rate of working fuel as it enters the working chamber and for increasing the flow rate of the working fuel as it is released therefrom, so that the rate of injection increases gradually at the outset of fuel injection but rapidly drops at the completion of the injection.

Fuel injector for an internal combustion engine

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.

Method and apparatus for operating direct injection type internal combustion engine

PURPOSE:To control the air-fuel ratio of an internal combustion engine accurately, by correcting fluctuation or variation of the injection quantity of fuel by providing an air-flow sensor for detecting the quantity of intake air supplied to the engine and a control unit for controlling the driving signal for a fuel injector. CONSTITUTION:An air-flow sensor 5 detects the quantity of air supplied to an internal combustion engine 3, and the output of said sensor 5 is furnished to a control unit 4. A fuel injector 1 has an actuator for pressurizing fuel that is formed in a unitary manner. The control unit 4 controls the driving signal for the fuel injector 1 to keep a predetermined relationship between the integral value of the air quantity and that of the driving quantity of the fuel injector 1 within a prescribed period. Thus, since fluctuation or variation of the injection quantity of fuel is corrected, it is enabled to control the air-fuel ratio accurately.

A piezoelectric actuator comprising a tubular casing and an elongated piezoelectric member disposed in the casing. The piezoelectric member has axially spaced ends, one of which abuts the shoulder of the casing. The piezoelectric member expands and contracts in response to an applied voltage, another end effecting a pumping operation. The piezoelectric member forms first and second longitudinal surfaces extending along substantially the entire length of axis. The piezoelectric member is formed as a lamination of a plurality of piezoelectric plates, to each of which is applied an electrode element on one of lateral surfaces. The electrode elements protrude on the first or second surfaces, alternately. First and second electrode members are located at the first and second surfaces, respectively. The first surface may be a surface of an opening which extends through the piezoelectric member, and the second surface may be a surface of an outer cylindrical surface of the piezoelectric member. Since the outer cylindrical surface is kept in contact with the inner surface of the casing, no flashover occurs between the surfaces. The second surface also may be a surface of another opening which extends through the piezoelectric member. In this embodiment, since the outer cylindrical surface has no electrode element, no flashover occurs between the outer cylindrical surface and the inner surface of the casing. A valve apparatus having the above-mentioned actuator and a method of manufacturing a piezoelectric member are also disclosed.

Piezoelectric actuator, and valve apparatus having actuator

A method and apparatus for driving a capacitive-type load using a direct current power source, a charging circuit connected in series to the load, a discharging circuit connected in parallel to the load, and an electric circuit for controlling the charging and discharging circuits, and wherein at least one of the charging and discharging circuits has a primary coil, and a secondary coil coupled to the primary coil restores energy, generated when the charging or discharging is turned OFF, to the power source. This provides a highly efficient driving by a restoration of energy.

Toshihiko Igashira

Papers

Fuel injector for an internal combustion engine

Method and apparatus for operating direct injection type internal combustion engine

Fuel injection apparatus

Piezoelectric actuator, and valve apparatus having actuator

Method and apparatus for driving capacitive-type load