Nippon Soken, Inc.

Toyota Jidosha Kabushiki Kaisha

Toyota Jidosha Kogyo Kabushiki Kaisha

Nippondenso Co., Ltd.

Seiko Abe

Toshihiko Igashira

Yasuyuki Sakakibara

Toru Yoshinaga

Kazuhide Watanabe

Hisasi Kawai

Ken Nomura

Akihiro Izawa

Kiyonori Sekiguchi

Yukihiro Natsuyama

Masahiro Tomita

Takeshi Tanaka

Kazuo Shinoda

Yasuhiko Ishida

Hidetaka Nohira

Toshikazu Ina

Hitoshi Yoshida

Hiroshi Yorita

Nobuhiko Koyama

Yasuhiro Takeuchi

Kazuto Maeda

Kenzi Iwamoto

Eiji Hashimoto

Masayoshi Tokoro

Hiroshi Koide

Masahiro Takigawa

Mitiyasu Moritugu

Naoki Umeda

Yuzi Ishiguro

Shinichiro Kamohara

A fuel vapor purging system includes a container in which a set of divided chambers are formed by partition walls. Absorbent is disposed in the divided chambers. The divided chambers are sequentially connected to form a zigzag passage. Fuel vapor can enter the container from a fuel tank via a vapor line connecting the fuel tank and the container. In the container, an end of the vapor line faces the divided chamber which occupies an end of the set of the divided chambers. In the container, the fuel vapor is absorbed by the absorbent. Air can escape from the container via an opening in the container. The fuel vapor can be separated from the absorbent. The separated fuel vapor can be drawn into a suitable drawing device such as an engine air induction device via a purge line connecting the container and the drawing device. Fresh air can flow into the container via an air inlet provided on the container. Among the divided chambers, at least the divided chamber which occupies the end of the set of the divided chambers has a cross-sectional area equal to or smaller than 40 cm.sup.2.

Fuel vapor purging system

An internal combustion engine has an evaporated fuel purge system for directly feeding evaporated fuel of a fuel tank into an intake pipe of the engine during the engine is running. This system comprises a purge control valve for opening or closing a flow line which connects an upper space of the fuel tank with the intake pipe, a controller for controlling the operation of the valve, a throttle section formed in series with the purge control valve, and pressure and temperature sensors which are located on the upstream side of the throttle section for detecting a pressure and a temperature of the evaporated fuel. When a value detected by the pressure sensor exceeds a predetermined value of pressure for providing a critical pressure ratio at which a flow rate of the evaporated fuel at the throttle section substantially equals to a sonic velocity, the controller opens the purge control valve to cause a purged flow of the evaporated fuel whose flow rate is constant. Simultaneously, the controller calculates a purged flow rate of the evaporated fuel from the detected values of the pressure and temperature sensors and a time period during which the purge control valve is opened. On the basis of the calculated purged flow rate, a reduction correction is made to an amount of the fuel to be supplied to the engine in order to maintain an air-fuel ratio in the optimum condition. The calculated purged flow rate may be indicated.

Internal combustion engine with evaporated fuel purge system

An electrostrictive actuator which can be used, e.g., in a distributor type fuel injection device of a diesel engine has an electrostrictive actuator for generating an electric charge upon reception of a load and an electric circuit unit connected to the electrostrictive actuator. The electric circuit unit has an electric charge changing means for changing the electric charge of the electrostrictive actuator in the state of generation of electric charge due to a load exerted on the electrostrictive actuator and thereby constricting the electrostrictive actuator, and an electrical charging means for charging the electrostrictive actuator in the state of constriction due to the operation of the electric charge changing means when the load exerted on the electrostrictive actuator is reduced and thereby extending the electrostrictive actuator.

Electrostrictive actuator device and fuel injection device using same

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. A start and end of a fuel injection period, and a fuel injection ratio (a pilot fuel injection), can be controlled by the opening and closing of the valve.

Fuel injection pump for an internal combustion engine

A drive circuit for an electrostrictive element actuator for a fuel injection apparatus of a diesel engine. The drive circuit has a condenser adapted to be charged with electric charges generated by the electrostrictive element actuator; a combination of an electric charge transferring switching element and a rectifier element for becoming conductive in a first period and charging electric charges generated by the electrostrictive element actuator to the condenser; and a combination of an electric charge returning switching element and a rectifier element for becoming conductive in a second period, other than the first period, and returning electric charges stored in the condenser to the electrostrictive element actuator.

Drive circuit of electrostrictive element actuator in diesel engine fuel

A fuel injection system comprising a fuel injection pump, at least one fuel injection nozzle connected thereto, and a control device for varying the rate of injection of the system according to varying engine parameters. The control device has a variable volume chamber, the volume of which is varied by a piston located by a piezoelectric actuator. The variable volume chamber and a pumping chamber of the pump is intermittently connected by a passage which is specifically designed in such a manner that the fluid communication between the chambers, during the delivery stroke of a pump plunger, is provided only for an initial stage of the delivery stroke. A rate of injection is controlled in the initial stage to perform a pilot injection. In the subsequent stage, in which there is no need for rate-of-injection control, the variable volume chamber is isolated from the pumping chamber in order to relieve the piezoelectric actuator from an excessively high fuel pressure that would cause degradation of the piezoelectric elements.

Diesel engine fuel injection system with a rate-of-injection control

In an apparatus for controlling an electroexpansive actuator, a high voltage is applied to the electroexpansive actuator at a non-load state after an expansion and contraction operation thereupon is completed.

Apparatus for controlling electroexpansive actuator avoiding

A fuel injection apparatus including a fuel injector, a high pressure feed pump, and an auxiliary pump. The high pressure feed pump supplies highly pressurized fuel to the fuel injector while the engine is driven. The auxiliary pump supplies highly pressurized fuel at least on starting of the engine. The auxiliary pump is driven independent of the engine while the high pressure feed pump is driven by the engine.

Fuel injection apparatus for internal combustion engine

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.

Pump for supplying pressurized fuel to fuel injector of internal

A piezoelectric fuel injector for use in fuel injection systems of spark-ignition engines is provided with a normally closed valve assembly in the form of a reed valve. The valve assembly includes a valve plate having one or more outlet ports having an overall cross-sectional flow area sufficient to ensure an unobstructed flow path therethrough. The valve assembly also includes a generally flat, thin, resilient closure member cooperating with the valve set of the valve plate. The pressure wave created in the fuel in the pumping chamber upon excitation of the piezoelectric actuator propagates into the outlet ports to directly reach the thin closure member, which readily resiliently yields to permit a desired amount of fuel to be injected into the engine cylinders. The fuel injector is particularly suitable to be operated by a high-frequency drive signal in order to ensure precise metering of fuel quantity over a wide range of engine operating conditions.

Piezoelectric low-pressure fuel injector

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. The pressure in the pressure chamber is increased and decreased by the reciprocative movement of the piston, and by this increase and decrease of the pressure in the pressure chamber, the valve body is moved to connect the high-pressure fuel passage and the low-pressure passage to each other or to disconnect these passages from each other.

Piezoelectric control valve for fuel injector of internal combustion

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 piezoelectric actuator comprises a housing having an inside cavity in which is mounted a column of piezoelectric elements having interleaved electrodes. The column of piezoelectric elements is mounted within a sealed enclosure which divides the inside cavity of the housing into an inner space receiving the column of piezoelectric elements and an outer space. The inner space is filled with a flowable, electrically insulative, thermally conductive material such as silicone oil held in direct contact with and in a heat transfer relationship with the column of piezoelectric elements. The silicone oil serves to isolate the column of piezoelectric elements and the electrodes from moisture and other foreign materials that would otherwise affect an insulation breakdown voltage. A cooling liquid is adapted to be circulated through the outer space surrounding the enclosure to absorb heat transferred thereto from the column of piezoelectric elements through the flowable thermally conducting material. The piezoelectric actuator may be incorporated with a fuel injection nozzle to form a pump injector which pressurizes and injects fuel at each energization of the column of piezoelectric elements.

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Okazaki, Japan

Seiko Abe