Hitachi, Ltd.

Hitachi Automotive Systems, Ltd.

Other

Hitachi Car Engineering Co., Ltd.

Hideki Machimura

Yukio Takahashi

Masayoshi Kotaki

Yoshikazu Hoshi

Minoru Hashida

Takefumi Yamamura

Yoshinobu Ono

Hiroyuki Yamada

Noboru Baba

Kazuo Ojima

Katsuyoshi Terakado

Shizuka Yamaguchi

Arata Kagiyama

Satoshi Usui

Shingo Tamura

Masahiko Hayatani

Shunsuke Aritomi

Tatsuo Kawano

Akihiro Munakata

Masashi Nemoto

Hideaki Yamauchi

Syunsuke Aritomi

Noriyuki Maekawa

Kenichiro Tokuo

Masami Abe

Kiyotaka Ogura

Atsuji Saito

Masaya Takahashi

Daisuke Kitajima

Kazutaka Hosokawa

Shogo Sawada

Toshiaki Nagayama

A high-pressure fuel supply pump including an electromagnetically driven intake valve is configured such that a pressure equalizing hole is provided in the valve stopper positioned between the valve and a pressurizing chamber. The pressure equalization hole connects a spring storage space, provided between a valve and a valve stopper, with a surrounding fluid passage. The high-pressure fuel supply pump is further configured such that an opening of the pressure equalizing hole at the spring storage chamber side is open at a position at the inner side of a diameter of the spring. Since the pressure in the pressurizing chamber can be introduced into the inner side of the spring without traversing the spring, the unstable behavior of the spring or the valve due to the introduced pressure eliminated. Since the force applied to the valve when the valve closes is stabilized, the closing timing of the valve is stable.

High-pressure fuel supply pump including an electromagnetically driven intake valve

A high-pressure fuel supply pump includes a discharge valve, which is a non-return valve between a pressurizing chamber and a discharge port. The discharge valve includes a valve body housing, a discharge valve spring, a valve body and a seat member. The discharge valve is a flat valve. When the valve is opened, a flow of fuel moving from the pressurizing chamber and axially colliding with the valve body is radially distributed in the radial direction of the valve body to become a flow directly moving the discharge ports and a flow colliding with an inner wall of the valve body housing before moving toward the discharge ports and then in a circumferential direction of the valve body.

High-pressure fuel supply pump and discharge valve unit used therein

In order to provide a welded structure of and welding method for two metallic parts fitted together at a tubular section in a high-pressure fuel supply pump, an electric current is supplied to any of the welding connection surfaces formed between a pump housing and cylinder in a high-pressure fuel supply pump, between the pump housing and an installation flange, between the pump housing and an intake or discharge joint, between the pump housing and a pulsation-absorbing damper cover, between the pump housing and a relief valve mechanism, and between the pump housing and an electromagnetically driven intake valve mechanism. The two sections are pressed against each other to generate, along the connection surface, a plastic flow not causing melting or fusion due to heat, and form a diffusion-weld region at the connection surface by using the plastic flow and the application of the pressure.

High-pressure fuel supply pump and the manufacturing method

A fluid pressure pulsation damper mechanism includes: a metal damper having two metal diaphragms joined together with a hermetic seal for forming a sealed spacing filled with a gas between the two metal diaphragms, an edge part overlapping along outer peripheries thereof, a main body having a damper housing in which the metal damper is accommodated, and a cover attached to the main body to cover the damper housing and isolate the damper housing from outside air.

Fluid pressure pulsation damper mechanism and high-pressure fuel pump equipped with fluid pressure pulsation damper mechanism

An object of the present invention is to reduce the pressure loss in a relief valve employed for a high-pressure liquid supply pump. Disclosed is a high-pressure liquid supply pump for pressurizing a liquid and supplying the pressurized liquid from a low-pressure side to a high-pressure side. The pump includes a relief path which releases the pressurized liquid from the high-pressure side to the low-pressure side, and a relief valve which is positioned in the relief path and equipped with an intermediate chamber, a valve seat positioned toward the high-pressure side of the intermediate chamber, a ball valve that is attachable to and detachable from the valve seat, and a ball valve retainer for pressing the ball valve against the valve seat. The relief path is configured so that an inflow path to the intermediate chamber and an outflow path from the intermediate chamber both produce a restriction effect. The ball valve retainer has a pressure reception surface for receiving the pressure from the intermediate chamber. A first pressure reception area, which detaches the ball valve from the valve seat upon receipt of liquid pressure of the pressurized liquid from a high-pressure section when the relief valve closes, is smaller than a second pressure reception area, which lifts the ball valve and the ball valve retainer upon receipt of liquid pressure from the intermediate chamber.

High-pressure liquid supply pump

Disclosed herein is a fuel pump for an inter-cylinder direct fuel injection apparatus, in which occurrence of corrosion and attrition caused by cavitation or erosion can be suppressed, their resistance against the environment can be improved, and an excellent lifetime can be achieved in the case of the use of an aluminum material even if the temperature reaches as high as 100&#xb0; C. or higher and the pressure reaches as high as 7 to 12 MPa. In the fuel pump for an inter-cylinder direct fuel injection apparatus, made of aluminum or an aluminum alloy, a coating film plated with Ni&#x2014;P or a Ni&#x2014;P based material is formed by electroless plating.

Fuel pump for inter-cylinder direct fuel injection apparatus

A fuel pump, of which sliding mechanism parts in its fuel chamber have good wear resistance under a severe environment, and a direct fuel injection engine using the fuel pump are provided. In a fuel pump for pressurizing and delivering fuel to a fuel injector of a vehicle engine, at least one of sliding surfaces of a slant plate, a slipper and a plunger sliding in a lubricating oil and at least one of sliding surfaces of sliding members of a plunger and a cylinder contacting with and sliding on each other through the fuel are formed of a hardened layer composed of any one of a nitrided layer, a carburization quenched layer and a carbonitrided layer, or coated with a high corrosion resistant and hard metal compound layer over the hardened layer.

Fuel pump and direct fuel injection engine

A seal mechanism with improved pressure tightness is provided to eliminate a return piping to a fuel tank used for reducing pressure applied to the seal mechanism in a high pressure fuel pump. The seal mechanism includes a stress reduction mechanism for reducing the stress generated at the junction between its retaining member and flexible member.

Seal mechanism and fuel pump provided therewith

In a fuel pump pressurizing fuel and supplying the fuel to a fuel injection valve of a vehicle engine, a hardened layer of at least one selected from a nitride layer, a carburated and quenched layer and a carbonitrided layer, and a metal compound layer, on a surface of the hardened layer, higher in corrosion resistance than the hardened layer are formed on one of slide surfaces contacting each other and sliding in fuel.

Fuel pump, in-cylinder direct injection type internal combustion engine using the same and surface treatment method

An axial plunger pump which does not need bellows by restricting fuel to a cylinder bore configuring a pump portion and by lubricating the other portion with oil. The high pressure fuel pump includes a plunger reciprocating according to a shaking movement of a swash plate, a cylinder block forming a pump chamber together with the plunger, and a sealing member provided between the plunger and a cylinder bore for sealing oil leaked from the pump chamber to a chamber surrounding the pump chamber, wherein oil in the oil chamber is supplied from the outside of the high pressure fuel pump.

High pressure fuel pump

The present invention provides an axial plunger pump which does not need bellows by restricting fuel to a cylinder bore configuring a pump portion and by lubricating the other portion with oil. The high pressure fuel pump comprises a plunger reciprocating according to a shaking movement of a swash plate, a cylinder block forming a pump chamber together with the plunger, and a sealing member provided between the plunger and a cylinder bore for sealing oil leaked from the pump chamber to a chamber surrounding the pump chamber, wherein oil in the oil chamber is supplied from the outside of the high pressure fuel pump.

An axial plunger pump includes a shaft having a swash plate effecting swing motion and transmitting driving force from the outside, plungers reciprocate by the swing motion of the swash plate. A cylinder block has cylinders formed so as to open on the side of the swash plate, with the plungers inserted therein. Passages in the block supply refuel to the cylinders. A body combined with the cylinder block encloses the swash plate. Sealing members are arranged between the plungers and the cylinders on the swash plate side of the passages formed in the cylinder block for sealing gaps between the plungers and the cylinders, respectively.

The drive part for converting the revolution movement to the wobble movement is composed of the shaft for transmitting the drive force from outside, the swash plate rotated by the shaft and the wobble plate for converting the revolution movement of the swash plate to the wobble movement. Plural pistons are reciprocated in responsive to the wobble movement of the wobble plate. The crank room containing the swash plate, the wobble plate and the piston is separated into the fuel room and the drive room by the bellows. The bearings for transmitting the drive force between the shaft in the drive room and the swash plate, and the bearing for transmitting the drive force between the swash plate and the wobble plate are placed inside the drive room in order to lubricate the bearings. By arranging plural pistons inside the fuel room, the fuel is forced to be taken in and discharged by the reciprocate movement of the individual pistons.

Fuel pump

A motion converting mechanism for converting the rotating motion to the inclined gyration movement in a fuel pump is isolated from gasoline through a flexible isolating member. The lubrication of a load supporting portion in the fuel pump, which is enclosed in an interior portion of the flexible isolating member, can be performed. A sealing portion of a rotating shaft in the fuel pump is isolated from the gasoline by the flexible isolating member. The lubricating oil is sealed in an interior portion of an isolating area formed by the flexible isolating member.

Growing community of inventors

Hitachinaka, Japan

Hideki Machimura