Nok Corporation

Masatoshi Okada

Yosuke Kondo

Junichi Nakayama

Shinji Nagasawa

Katsutoshi Ishioka

Yasuaki Tanabe

Sosuke Ito

Kazuki Takeno

Iwao Taira

Tadashi Abiko

Ichiro Yamane

A high performance sealing device having an excellent pressure resistance and realizing a prevention of damage. The sealing device usable at a working pressure of 0 to 2 MPa, and not damaged even if the pressure of high-pressure fuel of 5 MPa or higher is applied thereto, wherein high pressure fuel on the high pressure side is sealed by a first seal part, oil from a cam side on a low pressure side is sealed by a second seal part, and the fuel slightly leaked due to failure of scraping at the first seal part is sealed by the second seal part to form a dual seal structure. A resin ring coming into slidable sealing contact with a shaft is used in the first seal part, whereby abnormal abrasion does not occur even when fuel having less lubricity is used, and the durability of the seal is increased.

Sealing device

There is provided a plunger seal () for a fuel injection pump for a direct-injection gasoline engine, in which, even if a resin material is used for a fuel seal member (), the plunger seal can be made compact, sealing ability is increased, and assembling man-hours can be reduced, and in which set sealing performance can be achieved when a U-shaped elastic member () for applying an energizing force in a diametrical direction is used in a groove () formed in the fuel seal member (). The resin fuel seal member () and an oil seal member () are assembled to form one seal system. Further, when the U-shaped elastic member () is installed in the groove (), an axial position (L) of an end surface () at the side opposite to the sealed object of a fixing collar () formed on an inner peripheral surface of the groove () is positioned at the side (B) opposite to the sealed object than the axial position (L) of a leading end portion () of a seal lip () of the fuel seal member ().

Plunger seal for pump

Growing community of inventors

Mito, Japan

Masatoshi Okada