Hitachi Automotive Systems, Ltd.

Honda Motor Co., Ltd.

Hitachi Astemo Ltd.

Atsushi Takaoku

Masahiro Soma

Shusuke Akazaki

Motoyuki Abe

Kiyotaka Ogura

Yasuo Namaizawa

Hideharu Ehara

Satoshi Usui

Tohru Ishikawa

Takehiko Kowatari

Takao Miyake

Eiji Ishii

Minoru Hashida

Masahiko Hayatani

Shigehiko Omata

Moritsugu Akiyama

Yusuke Irino

Yuta Yanagisawa

Masanori Mifuji

The present invention provides a fuel pump capable of preventing the occurrence of cavitation near a seat member in a valve mechanism. The fuel pump includes a plunger adapted to reciprocate, a pressurizing chamber adapted to increase and decrease its volumetric capacity through the reciprocation of the plunger, and a relief valve mechanism adapted to return a fuel to the pressurizing chamber. The relief valve mechanism includes a relief valve, and a seat member having a valve contact portion for seating the relief valve thereon. The relief valve is disposed closer to the plunger than the seat member. The seat member has an annular groove portion which forms a space communicating with the pressurizing chamber, between the annular groove portion and a second chamber (a fixing portion) surrounding the outer peripheral surface of the seat member. The space is provided at a position farther from the plunger than the valve contact portion.

Fuel pump

It is important not to form the partial bump in the collision structural part, however the fixed core and the movable core are relatively inclined due to an accumulation of tolerances and therefore even if each collision structural part of the fixed core and the movable core in formed in a flat shape, the fixed core and the movable core are contacted with not the whole of the collision structural parts but a part of the collision structural parts at the moment of the collision. In a case in which the collision structural part is formed in a ring shape or an intermittent ring shape, the fixed core and the movable core are contacted with each other at outer peripheral parts. Thus, when the fixed core and the movable core are collided with each other, a high stress is applied to the outer peripheral parts contacted first. Accordingly, the shape of the outer peripheral parts of the collision structural parts is important, however since such a part, which is a tiny protruding shape, requires high processing accuracy, to reduce stress occurred during collision while keeping productivity is difficult. In the present invention, an R-shaped part and a flat part are provided in order from an outer peripheral side of a collision structural part. Further, the R-shaped part and the flat part are connected in a tangent manner.

Electromagnetic valve

A fuel injection valve is provided that can reduce variations in stroke length by reducing distortion during welding, and consequently can reduce variations in flow rate of injected fuel. The fuel injection valve has a nozzle; a fixed valve that is press-fit into a tip of the nozzle and has a fuel injection port from which the fuel is injected; and a movable element that forms a fuel seal section by abutting against the fixed valve, and opens and closes the fuel injection port. The fixed valve and the nozzle are fixed in place by welding at a position with no space due to press-fitting. A groove that serves as an empty space is provided in a continuation of a welded section that is formed in the fixed valve and the nozzle by the welding.

Fuel injection valve

In a fuel injection device having a sensor for detecting a state in the combustion chamber in a free end thereof, the noises that may be generated in the sensor signal transmitting member for transmitting the sensor signal are minimized. The fuel injection device comprises: a valve body () having a free end exposed to the combustion chamber () defined in the engine main body () and a base end located outside of the engine main body; a sensor () supported at a free end of the valve body to detect a state of the combustion chamber; an actuator () received in the valve body; a sensor signal transmitting member () extending from the sensor to the base end of the valve body; a drive signal transmitting member () extending from the actuator; and a first shield member () interposed between the sensor signal transmitting member and the drive signal transmitting member, the first shield member having an electro-conductive property and being grounded.

Fuel injection device

An object of the invention is to provide a fuel injection valve that applies a swirl to an upstream side of a seat section to shorten spray penetration. When flows into injection hole entries are indicated by arrowstoand injection hole exit directions are indicated by arrowsto, an angle &#x3b1; defined by the inflow directionand the exit directionof an injection holecan be increased. In a method for applying the twisted angle &#x3b1;, a side grooveon an outer peripheral side of a guide memberis set to be accompanied with a twist with respect to an axis O. Furthermore, a flow passage area of the side grooveis set smaller than a flow passage area on an upstream side of the guide memberand is also set larger than a flow passage area of a seat sectionB that is constructed by a gap between a valve bodyand an orifice cup

In a fuel injection device having a sensor for detecting a state in the combustion chamber in a free end thereof, the sensor signal transmitting member for transmitting the sensor signal is protected from vibrations and moisture. The fuel injection device comprises: a valve body () having a free end exposed to the combustion chamber () defined in the engine main body () and a base end located outside of the engine main body; a sensor () supported at the free end of the valve body to detect a state of the combustion chamber; a sensor signal transmitting member () extending from the sensor to the base end of the valve body along an exterior of the valve body to transmit a signal from the sensor; and a second resin portion () and/or a bonding agent () covering the sensor signal transmitting member and securing the sensor signal transmitting member onto an exterior of the valve body.

A fuel injection valve that injects fuel directly into a cylinder of an internal combustion engine includes: a nozzle inserted into a fuel injection valve fitting hole formed in the cylinder; a cylindrical tip seal holder attached to the nozzle; and an annular seal member that is fitted to the tip seal holder and seals between an inner circumferential surface of the fuel injection valve fitting hole and an outer circumferential surface of the tip seal holder.

In a fuel injection valve, it is intended to enhance valve-closing responsivity while maintaining durability (anti wear property) of a collision portion between a stationary core and a movable core and valve-opening responsivity. An annular end faceA of the movable corein the fuel injection valve is provided with a collision portionC that collides to a stationary corewhen the movable core is magnetically attracted toward the stationary core side and a non-collision portion that keeps a fluid gap between both cores at an area of an outer side or an inner side from the collision portion. The annular end faces of the stationary core and the movable core are coated with platingshaving anti wear property, and at least one of the platings of the stationary core and the movable core is formed in such a manner that the thickness thereof at the collision portionC is to be thicker and the thickness thereof at the non-collision portion is to be thinner.

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Hitachinaka, Japan

Atsushi Takaoku