Nippon Soken, Inc.

Toyota Jidosha Kabushiki Kaisha

Nippondenso Co., Ltd.

Kazuhide Watanabe

Yasuyuki Sakakibara

Toshihiko Igashira

Seiko Abe

Toru Yoshinaga

Yoshihiro Tsuzuki

Hiroshi Yorita

Masahiro Takigawa

Yukihiro Natsuyama

Yasuhiro Takeuchi

Terutoshi Tomoda

Takehiko Kato

Moriyasu Gotoh

Akira Shibata

Nobuyuki Murate

Shigeki Daido

Kou Ohtsuka

A solenoid-operated hydraulic control valve is disclosed which may be employed in a fuel injection system for an internal combustion engine. The hydraulic control valve has a valve plunger which is drawn by a solenoid when turned on for selectively establishing and blocking fluid communication between an inlet and an outlet. A fluid chamber is formed to which fluid pressure is supplied from the inlet. The fluid pressure in the fluid chamber acts on the valve plunger in a direction opposite to that of the attracting force of the solenoid when turned on for compensating the attracting force produced by residual magnetism in the solenoid immediately after the solenoid is turned off.

Solenoid-operated hydraulic control valve for use in fuel injection

A common-rail fuel injection system for an engine includes a fuel injector having a nozzle hole. A common rail stores high-pressure fuel. The common rail is connected to the fuel injector to feed the high-pressure fuel thereto. A movable nozzle needle disposed in the fuel injector blocks and unblocks the nozzle hole in accordance with movement thereof. A back pressure control chamber defined in the fuel injector is connected to the common rail to receive the high-pressure fuel therefrom. The nozzle needle is urged in a direction of blocking the nozzle hole in response to a pressure in the back pressure control chamber. A fuel chamber defined in the fuel injector is connected to the common rail to receive the high-pressure fuel therefrom. The nozzle needle is urged in a direction of unblocking the nozzle hole in response to a pressure in the fuel chamber. A fuel-pressure-responsive 2-way valve controls the pressure in the back pressure control chamber. An electromagnetic valve changes a state of the fuel-pressure-responsive 2-way valve. The fuel injector and the fuel-pressure-responsive 2-way valve are combined into a single unit. The electromagnetic valve is separate from the fuel injector.

Common-rail fuel injection system for an engine

A diaphragm-type pump includes a disk-like diaphragm made of an elastic material which is held between an upper housing and a lower housing. In this diaphragm-type pump, the diaphragm, which has a flat shape before it is mounted in the pump, is bent along a diaphragm stopper and mounted in the pump. Consequently, an urging force is constantly applied to the diaphragm in such a direction as to press it on the diaphragm stopper. The diaphragm is deformed in response to reciprocation of a plunger, and when the plunger reaches the bottom dead center and a cylinder chamber is decreased in pressure, the diaphragm is pressed on the diaphragm stopper by the urging force toward the diaphragm stopper and a feed pressure of a feed pump.

Diaphragm-type pump

A fuel injector wherein a piston driven by the extension and contraction of a piezoelectric actuator changes the pressure of a working fluid in a variable pressure chamber and back pressure chamber so as to drive a needle valve to open and close a fuel injection hole, wherein undesirable secondary injection after a main injection in prevented by providing a throttle portion for narrowing the communicating passage between the variable pressure chamber and back pressure chamber when the piston moves forward and the needle valve closes the fuel injection hole.

Fuel injector for internal combustion engine having throttle portion

A hydraulic valve drive device for intake/exhaust valves of an internal combustion engine using an oil pump similar to a distributor type injection pump. A plunger rotates and engages in reciprocating motion to pressurize hydraulic fluid taken into a pressure chamber and opens to discharge the same into a hydraulic cylinder of a specific intake/exhaust valve in register with the passage. The intake/exhaust valve maintains its valve lift to continue remaining open when the supply of the hydraulic fluid is stopped, but closes when the plunger rotates so that the passage is communicated with a relief channel and the relief valve opens.

Valve drive device

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.

Fuel injector and fuel injection system

A color apparatus includes an electroexpansive actuator, a unit for supplying a charge to the electroexpansive actuator, and a unit for controlling an amount of charge discharged from the electroexpansive actuator, and a stroke of the electroexpansive actuator is controlled in accordance with the amount of charge discharged therefrom. When such an electroexpansive actuator is applied to a control apparatus for a fuel injection valve, a fuel injection amount per ON/OFF operation of the fuel injection valve or a fuel injection rate can be freely controlled.

Control apparatus for electroexpansive actuator enabling variation of

A piezoelectric flow control valve comprising a slidable closure member (22) for controlling a flow of fluid through a fluid passage (42) between a fluid inlet (40) and a fluid outlet (32). The closure member (22) is biased toward a normally closed position by a plunger (70) responsive to a hydraulic pressure in a pressure chamber (78) which is in fluid communication with the fluid inlet (40) through a restriction and with a pumping chamber (96) of a piezoelectric pump (72). In order to prevent fluid leakage under situations wherein the fluid pressure at the fluid inlet (40) is not high enough to ensure closure of the member (22), the present invention provides spring biased pressure mechanism (106) for biasing the closure member (22) toward the normally closed position and override means (130) for overriding the pressure mechanism (106) in response to a predetermined pressure at the fluid inlet (40).

Piezoelectric flow control valve

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.

Fuel amount control system in an internal combustion engine

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.

Pressure responsive fuel injector actuated by pump

A fuel injection apparatus for an internal combustion engine, which comprises an accumulator for storing therein pressurized fuel while maintaining the pressure thereof at a predetermined high level. A fuel injection valve is arranged to inject the pressurized fuel in the accumulator into a combustion chamber of the engine. The injection valve is controlled to open and close by an output signal from an external control unit. A pressurizing pump is arranged to pressurize the fuel delivered from a fuel-feed pump and to supply it into the accumulator through a check valve. A work controlling device is arranged to control the amount of the fuel supplied from the pressurizing pump through the check valve into the accumulator in accordance with the variation of the amount of the fuel in the accumulator so as to decrease the amount of the fuel supplied from the pressurizing pump through the check valve into the accumulator when the amount of the fuel in the accumulator is increased and to increase it when the amount of the fuel in the accumulator is decreased.

Fuel injection apparatus for an internal combustion engine

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. The linear expansion of the sleeve due to a change in the ambient temperature causes the first piston to displace in one direction together with the piezoelectric actuator supported thereby so that the linear expansion of the piezoelectric actuator occurring in the opposite direction due to a similar ambient temperature change is counterbalanced whereby the second piston, serving as an output member of the piezoelectric actuator, is maintained at a constant distance with respect to the valve member regardless of change in the ambient temperature. Such a temperature compensation structure enabling precise positioning of the second piston ensures improved injection timing and injection quantity control of a fuel injection system for an internal combustion engine.

Piezoelectric hydraulic control valve

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.

Piezo-type valve

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.

Flow control device

A fuel evaporator for an internal combustion engine, which is provided with a ceramic heater, is disclosed. The fuel evaporator comprises a plurality of layered thin PTC ceramic plates, each of which has a plurality of open holes, electrodes which are provided on an upper surface, an under surface and between adjacent ceramic plates, and an insulator for securing the outer periphery of the layered PTC ceramic plates to the wall defining an air-fuel passage of an engine. The ceramic plates are electrically connected to one another in parallel so that each ceramic plate is rapidly heated by consuming only a small amount of electric power.

Growing community of inventors

Toyohashi, Japan

Kazuhide Watanabe