Hitachi Automotive Systems, Ltd.

Atsushi Nakai

Takao Miyake

Kiyotaka Ogura

Yoshio Okamoto

Yoshihito Yasukawa

Takahiro Saito

Masashi Sugaya

Nobuaki Kobayashi

Ryo Kusakabe

Hiroshi Ohno

Motoyuki Abe

Noriyuki Maekawa

Eiji Ishii

Akiyasu Miyamoto

Kazuki Yoshimura

Akira Iizuka

Recent exhaust gas regulation requires reduction of an amount and quantity of particulate matter included in an exhaust gas, and a normal maximum fuel pressure may be increased to approximately 35 MP. When the normal maximum fuel pressure is 35 MPa, a fuel injection valve is required to work for example at a pressure up to 45 MPa. In such a condition, a fluid force may exceed a valve opening force depending on a seat diameter, and a needle valve cannot be kept open and closed, when opening thereof is required. In order to solve the above problems, a fuel injection valve according to the present invention includes a valve seat portion, a valve body which is seated on or separated from the valve seat portion, an injection hole which is formed on a downstream side from the valve seat portion, and a guide portion which is formed on an upstream side from the valve seat portion seating a valve body seat portion of the valve body to guide a guided portion on a downstream side of the valve body, in which the valve seat portion is formed to have a dimension in a crossing direction crossing an axial direction of 0.4 to 0.8 times a dimension of the guide portion in the crossing direction.

Fuel injection valve

An object of the present invention is to provide a fuel injection valve which has a structure where failure hardly occurs in a valve member and a peripheral member thereof at the time of press-fitting of a fixed core. The present invention provides a fuel injection valve that includes: a valve memberA; an anchorwhich is relatively displaceable with respect to the valve memberA; a fixed corein which a through-holeA is formed; a gap forming memberwhich forms a gap between an engagement portionB on the valve member side and an engagement portionD on the anchor side; and a biasing springwhich biases the gap forming memberin a valve closing direction. The engagement portionsD andB are provided in both the anchorand the valve memberA so as to be engaged with each other when the anchoris displaced in a valve opening direction with respect to the valve memberA, thereby regulating the displacement of the anchorin the valve opening direction. An outer diameter of the gap forming member, an outer diameter of the biasing spring, and a maximum outer diameter of the valve memberA are set to be smaller than an inner diameter of the through-holeA.

A fuel injector is provided. A movable iron core is provided relatively displaceable to a valve body. A fixed iron core is opposed to the movable iron core. A first spring member energizes the valve body in a valve closing direction. A second spring member energizes the movable iron core in a valve closing direction. Contact portions are in contact with each other in a case where the movable iron core displaces in a valve opening direction with respect to the valve body. A gap is formed between the contact portions in a valve closing state. In a state in which the movable iron core and the valve body move in different directions after the movable iron core collides with the fixed iron core while a valve is opened, a spring force is not applied between the movable iron core and the valve body.

Fuel injector

A fuel injection valve includes: a valve member; an anchor configured to be relatively displaceable in a valve opening-and-closing direction with respect to the valve member; a fixed core; a first spring biasing the valve member in a valve closing direction; a second spring biasing the anchor in the valve opening direction from an opposite side of the fixed core; and a third spring biasing the anchor in the valve closing direction from the fixed core side and has a biasing force smaller than a biasing force of the first spring and larger than a biasing force of the second spring where engagement portions are provided in both the anchor and the valve member to be engaged with each other when the anchor is displaced in the valve opening direction with respect to the valve member, thereby regulating the displacement of the anchor in the valve opening direction.

A fuel injection valve includes a valve element movably disposed to a valve seat member having a valve seat and formed with an opening located at a downstream side thereof. A swirl imparting chamber is formed to impart a swirl force to fuel within the swirl imparting chamber by turning fuel. An injection hole is opened to the bottom of swirl imparting chamber to inject fuel to outside. Additionally, a communication passage is formed to connect the swirl imparting chamber with the opening of the valve seat member. In this fuel injection valve, the swirl imparting chamber and the communication passage are formed to satisfy the following equation:0.15&#x2266;&#x3c;0.5

In a fuel injection valve, a pipe line through which fuel is uniformly caused to flow is supposed from a flow quantity of fuel flowing into each of communication passages which is communicated between a corresponding one of a plurality of swirl generating chambers and an opening section of a valve seat member and, if a diameter of the pipe line is assumed to be da and a diameter of each of injection holes is assumed to be d, da/dis set such that a spray angle of fuel injected from each of the injection holes provides a desired spray angle and the communication passages and the injection holes are designed such that at least one of fuel sprays injected from the respective injection holes is contacted on any other fuel sprays at a lower position than a liquid film part.

A fuel injection valve is disclosed with enhanced uniformity of a swirl flow in the circumferential direction. The valve includes a swirling chamber having an inner wall surface with a helical curve and a swirling passage for guiding fuel into the chamber. The valve is formed such that the center of a circle as the basis of the helical curve and the center of a fuel injection hole open in the swirling chamber align with one another. The joint between the passage for swirling and the inner circumferential wall on the downstream side of the chamber at which both walls intersect is positioned between a line from the center of the hole to a point at which the curvature of the swirling chamber shape starts to change; and a tangent line of the side wall of the hole so drawn that it is in parallel to the line segment.

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Hitachinaka, Japan

Atsushi Nakai