Nok Corporation

Yasuaki Tanabe

Junichi Nakayama

Yosuke Kondo

Shinji Nagasawa

Katsutoshi Ishioka

Masatoshi Okada

Sosuke Ito

Kokichi Hamamoto

Tamio Inamura

Koichi Mizunoya

Takeo Otani

A resin lip type seal () capable of increasing safety against rupture by reducing rigidity of a plate-like lip () bent around a tip point A of a approximately wedge-shaped recessed part () to reduce stress concentration at the point A, suppressing the lowering of sealability due to a reduction in creep of the lip, and increasing the follow-up capability of the lip to the eccentricity of its axis. Indentations are formed on the slidable contact surface () of the plate-like lip () or/and the anti-slidable contact surface () thereof. Indentations () are also formed on the sloped slidable contact surface () of the inner lip () of the seal. Then, the ratio of the portion of each of the slidable contact surfaces where the indentations () are formed is &#xbd; or more of each of the surface areas of the slidable contact surfaces ().

Lip type seal

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

Nihonmatsu, Japan

Yasuaki Tanabe