Hitachi, Ltd.

Unisia Jecs Corporation

Takayuki Kobayashi

Hideo Kato

Noriyuki Kumasaka

Shigekazu Otomo

Takeo Yamashita

Mitsuhiro Kudo

Juichi Morikawa

Masatoshi Yanase

Hiroaki Hirata

Hiroki Nakagane

A fuel injection valve has: a tubular body, a valve seat member, a valve body, a core tube, a bias spring, and an electromagnetic actuator. The core tube is press fitted into the tubular body. The core tube has a first end side opposing an absorption section of the valve body in such a manner as to form an axial gap interposed between the first end side of the core tube and the absorption section. The core tube has a second end side axially extending in the tubular body to a certain position on a way to the second end side of the tubular body. The axially extending second end side of the core tube has an outer periphery which is formed with a reduced diameter section for increasing an accuracy in positioning the core tube when the core tube is press fitted into the tubular body.

Method of manufacturing a fuel injection valve

Fuel injection valve

In a fuel injection valve, a substantially arc-shaped chamfered portion in a substantially arc shape of cross section is formed on an edge of an inner wall portion of each opening end of a corresponding nozzle hole of a nozzle plate to further expand a whole diameter of an injection stream of fuel passed through a plurality of obliquely penetrated nozzle holes. In a manufacturing method for the nozzle plate, circulating a fluid mixed with an abrasive through each nozzle hole is carried out to polish opening ends of the respective nozzle holes which are faced against the external of the fuel injection valve in a form of substantially arc shape of cross section with the abrasive. Furthermore, grinding the respective major surfaces of a punched plate material which becomes the nozzle plate together with vicinities to the respective opening ends of the nozzle holes is carried out.

Engine fuel injection valve and manufacturing method for nozzle plate used for the same injection valve

The invention discloses a magnetic recording and reproducing system using a composite magnetic head whose surface facing a magnetic recording medium is composed primarily of a ferromagnetic metal and a high permeability ferrite single crystal, and which has a region close to a gap and composed of the ferromagnetic metal, wherein the composite magnetic head is arranged in such a fashion that the {110} plane of the high permeability ferrite single crystal is made to substantially coincide with a plane forming a principal magnetic circuit of the composite magnetic head, that the &lt;100&gt; direction lying inside the {110} plane is inclined at an angle of from 15.degree. to 75.degree. with respect to a direction perpendicular to the surface facing the magnetic recording medium, and that the magnetic recording medium travels in a direction which is relatively the same as, and parallel to, a vector formed by projecting a vector extending from the inside to the outside of the surface facing the magnetic recording medium in the &lt;100&gt; direction, on the surface facing the magnetic recording medium. This magnetic recording and reproducing system can remarkably reduce the step occurring on the surface facing the magnetic recording medium due to wear caused by the travel of the recording medium, and can reduce any output deterioration and fluctuation resulting from the step.

Magnetic recording and reproducing system with composite magnetic head

Growing community of inventors

Gunma, Japan

Takayuki Kobayashi