Nippondenso Co., Ltd.

Denso Corporation

Takashi Iwanaga

Masahiko Miyaki

Hideya Fujisawa

Masaaki Kato

Hiromasa Aoki

Mitsuru Ban

Yasuhiro Kariya

Takayoshi Kawaguchi

Michiharu Miyata

Nobuhiko Shima

Yasunori Kiriki

Kenji Magario

In a fuel injection valve, a flow-out passage is provided on a downstream side thereof with an out-orifice. The out-orifice is provided around a periphery of an inlet opening thereof with an inlet circumferential edge with which a flow of fuel to be ejected from a pressure control chamber via the out-orifice is swirled so that turbulent flow is forcibly formed. Then, the turbulent flow is maintained until the fuel is ejected. Dimensions of the out-orifice satisfy the formulas, R/D&lE;0.2 and L/D&lE;1.2, where R is corner radius of the inlet circumferential edge of the out-orifice, D is inner diameter thereof and L is axial length thereof. Accordingly, fuel injection is stable with less fuel amount fluctuation in each cycle even when fuel pressure and temperature are relatively low.

Fuel injection valve

In a fuel injection nozzle for an internal combustion engine, a frictional force reducing member is interposed between a seating surface of a shoulder portion of a nozzle body and an inner seating surface of a bearing portion of a retaining nut, whereby a frictional force developed between both seating surfaces and can be diminished without performing a high-degree of surface machining on the inner seating surface of a bearing portion of the retaining nut, even if the surface roughness of the inner seating surface of a bearing portion of the retaining nut is large. Consequently, it is possible to prevent deformation of a slide portion of the nozzle needle which is attributable to a twist of the nozzle body caused by frictional force.

Fuel injection nozzle

A rapid-response solenoid-operated fuel injector for diesel engines is provided which includes a solenoid-operated valve member and a needle valve. The solenoid-operated valve member selectively establishes fluid communication between a fuel inlet and a fuel outlet. The needle valve is moved to selectively open and close a spray hole through which the fuel is sprayed. The solenoid-operated valve member is exposed at its head to the fuel pressure within a pressure control chamber supplied from the fuel inlet and has formed therein a pressure balancing chamber communicating with the pressure control chamber through a first orifice. The pressure of fuel within the pressure balancing chamber acting on the solenoid-operated valve member to block the fluid communication between the fuel inlet and outlet is balanced with the pressure of fuel within the pressure control chamber acting on the solenoid-operated valve member to establish the fluid communication between the fuel inlet and outlet. The pressure control chamber communicates with the fuel inlet through a second orifice which is smaller in diameter than the first orifice.

Solenoid valve and fuel injector for internal combustion engine using

In a system in which a common rail accumulates fuel pressurized by a high pressure supply pump, when a pipe connected to the common rail is damaged or a pulsation of fuel injection is caused in the system, reliability of the system is greatly affected because of high pressure. According to the present invention, a mechanism to prevent leakage of fuel from the common rail even when the pipe is damaged, or a mechanism to damp a pulsation of fuel pressure, is provided in a pipe close to the common rail. Therefore, reliability of the system is improved.

Accumulator type of fuel injection device

An accumulator fuel injection apparatus in which a nozzle element is divided into a first nozzle having one end side of said nozzle element and a second nozzle having the other end side of the nozzle element. The accumulator fuel injection apparatus comprises a stopper for setting a maximum movement position of the first nozzle toward the second nozzle, a second pressure control chamber communicating with a first pressure control chamber and forming a predetermined space or interval through which the first nozzle and the second nozzle are spaced away from each other under a condition that the first nozzle is arranged at the maximum movement position, and delay apparatus for delaying reduction of pressure within the first pressure control chamber due to the fact that fluid flows into a low-pressure chamber from the first pressure control chamber upon communication of the first pressure control chamber and the low-pressure chamber with each other. It is possible to easily perform operation of setting an amount of pre-lift of the nozzle needle which decides an injection rate, and operation of assembling constitutional elements thereof.

Accumulator fuel injection apparatus

A feel injection system for an engine controls a behavior of a nozzle needle for controlling a fuel injection timing and a fuel injection amount. The system controls a hydraulic pressure applied to the nozzle needle for displacing the nozzle needle between its fully opened position and its fully closed position. The system so controls the hydraulic pressure applied to the nozzle needle as to quickly displace the nozzle needle from the fully opened position to a given position which is located between the fully opened and closed positions, on the other hand, slowly displace the nozzle needle from the given position to the fully closed position so as to decrease an impact load applied to a valve seat for the nozzle needle when the nozzle needle is seated onto the valve seat.

Fuel injection system for engine

A Diesel fuel injection device has a pressure accumulation piping for accumualting a fuel at a high pressure and an injector for injecting the fuel supplied by the pressure accumulating piping. The injector including a nozzle needle operative to open and close an injection orifice and a three-way solenoid valve operative to control the fuel pressure acting on the nozzle needle. The three-way solenoid valve is controlled to actuate the nozzle needle and to cause the fuel in the pressure accumulation piping to be injected through the injection orifice. A control valve is provided to control the injection rate characteristic to provide a boot-type injection characteristic. A boot type invention characteristic that is defined by a first characteristic in which the injection rate is substantially constant for a predetermined time period, a subsequent second characteristic in which the injection rate is gradually increased from the first characteristic, and a subsequent third characteristic in which the injection rate is suddenly decreased from the second characteristic; whereby operation noise is be reduced.

Fuel injection device for diesel engines

A valve having a first valve body including a first contacting surface, a pressurized fluid supply path opening to the first contacting surface and a pressure-controlled chamber opening to the first contacting surface. A second valve body includes a second contacting surface contacting with the first contacting surface and a valve path whose ends open to the second contact surface, and which connects fluidly the pressurized fluid supply path to the pressure-controlled chamber. A valve is arranged in the second valve body and moved to a closed or open position at which the valve means does or does not cut off the fluidal connection between the pressurized fluid supply path and the pressure-controlled chamber. An actuator arranged on the second valve body moves the valve to the closed or opened position. A first drawing means presses the first contacting surface and the second contacting surface against each other. A second drawing means sets the actuator on the second valve body. The force of the first drawing means is not applied to the actuator and therefore the operation of the actuator is not disturbed by the force pressing the first contacting surface and the second contacting surface against each other. Also, the actuator can be removed from the valve without dissembling the first and second valve bodies.

Valve

A fuel injection control device in which a needle valve of a fuel injector is opened and closed by two valves. The fuel injector has a pressure control chamber and a fuel chamber, and the needle valve opens a fuel injection aperture to inject the fuel in the fuel chamber to the engine when a pressure in the pressure control chamber is relatively high. One valve is provided in a passage which connects a pump, the pressure control chamber, and a reservoir, and the other valve is provided in a passage which connects the pump, the fuel chamber, and the reservoir.

Fuel injection control device

A fuel injection system for a diesel engine has fuel pump driven by the engine for producing highly pressurized fuel, a common rail for storing the pressurized fuel therein and injection nozzles for injecting the pressurized fuel stored in the common rail into the engine. The injection nozzles are electrically controlled in accordance with engine operating conditions (N, .alpha.) by the use of injection control solenoid valves provided between the injection nozzles and the common rail. The fuel pump is electrically controlled in accordance with the engine operating conditions by the use of a spill control solenoid valve which spills the pressurized fuel to a low pressure fuel channel so that loss of engine torque required by the pump is reduced.

Growing community of inventors

Toyohashi, Japan

Takashi Iwanaga