Aisan Kogyo Kabushiki Kaisha

Yukinori Kato

Hikaru Kikuta

Hideaki Nishibu

Masami Hirata

Motoyuki Suzuki

Tomohiro Okubo

Takao Yamaguchi

An electromagnetic fuel injection valve wherein it is possible to prevent undesired adhesion between the respective abutting surfaces of an armature and a stationary core as well as to ensure the required wear resistance for the abutting surfaces and wherein the amount of lift of the valving element is unlikely to change is provided. After rough surfaces like satin-finished surfaces have been farmed on the abutting surfaces by shot peening, the rough surfaces are flattened by spotting. Therefore, the abutting surfaces can easily separate from each other without likelihood of adhering so closely that is difficult for them to separate from each other. Also, the amount of lift of the valving element is unlikely to change. Accordingly, the amount of fuel injected by the fuel injection valve is unlikely to change with passage of time. Thus, stable fuel supply can be performed.

Electromagnetic fuel injection valve and method for manufacturing same

An electromagnetic fuel injection valve wherein a central pipe part has satisfactory mechanical strength and an intermediate portion of the pipe part is surely made non-magnetic is provided. The electromagnetic fuel injection valve has a core surrounded by a solenoid coil. A valve housing is disposed forward of the core. The core and the valve housing are connected through a thin-walled portion. The wall thickness of the thin-walled portion is smaller than the wall thickness of the core and that of the valve housing. The core and the thin-walled portion, together with the valve housing, are formed in an integral structure. The thin-walled portion has a sufficient wall thickness to provide satisfactory mechanical strength. The thin-walled portion is modified into a high-hardness non-magnetic portion by a carbulizing treatment.

Electromagnetic fuel injection valve

A valve sound emitted from an operated injector is suppressed to be transmitted through a fuel passage in a core to a delivery pipe, thus reducing operating noise. A sound insulating member is fixed in the fuel passage in the core. It has been recognized that transmission of the sound is effectively suppressed even with a sound insulating member of such a size that does not prohibit fuel flow. Preferably, the sound insulating member is integrally assembled to a strainer. Noise from the operated injector is effectively reduced by the invention.

Growing community of inventors

Obu, Japan

Yukinori Kato