Nok Corporation

Yosuke Kondo

Junichi Nakayama

Kazunari Seki

Yasuaki Tanabe

Masatoshi Okada

Koji Watanabe

Yusuke Yoshida

Shinji Nagasawa

Hirotaka Mizuta

Katsutoshi Ishioka

Fangman Xu

Hideya Watanabe

Sosuke Ito

Wataru Tokunaga

Yuki Takao

Takuya Igawa

Keisuke Nakashima

Hikaru Tadano

Iwao Taira

Kokichi Hamamoto

Hiroaki Monma

Kazuki Takeno

Tamio Inamura

Tadashi Abiko

Ichiro Yamane

Koichi Mizunoya

Takeo Otani

A sealing device exhibits a sealing function even when it is in a state in which squeeze of a seal ring is reduced and in a low-temperature condition. A sealing structure is provided with a cylinder head () for an engine which has an injector mounting hole () and is exposed to high pressure gas; an injector which is mounted in the injector mounting hole (); and a seal ring () made of resin which seals an annular gap between the injector mounting hole () and the injector (), wherein a step having a larger diameter on a combustion chamber side (E) where the high pressure gas is present is formed on an inner peripheral surface of the injector mounting hole (), and the seal ring () is attached to a position where the seal ring is in close contact with a step surface () of the step.

Sealing structure

The sealing device includes: an outer peripheral ringthat is in contact with a side wall surface of an annular grooveat a low pressure side (L), and slides with respect to an inner peripheral surface of a shaft hole in a housingthrough which a shaftis inserted. An inner peripheral ringmade of a rubber-like elastic body that is in contact with an inner peripheral surface of the outer peripheral ringand a groove bottom surface of the annular groove, respectively. The outer peripheral ringis formed on its outer peripheral surface with a concave portionwhich extends from an end of a high pressure side (H) to a position which does not arrive at an end of a low pressure side, so as to introduce fluid thereinto from the high pressure side.

Sealing device

Sealing device and sealing structure

A sealing device () includes a resinous sealing ring () and an elastomeric elastic ring () in an annular groove. The sealing ring () has a cylindrical surface portion () making intimate contact with a groove bottom of the annular groove () and an inclined surface portion () expanding in diameter toward the atmosphere side (A). The elastic ring () is disposed such that at least its portion is compressed between the inclined surface portion () and the groove bottom of the annular groove () so as to press a portion of the sealing ring () on the atmosphere side (A) toward the outer peripheral side.

A seal ring that seals an annular gap formed between a shaft and a housing that has a shaft hole into which the shaft is inserted. The seal ring is configured such that one of both the ends and has a projection projecting in the direction of the circumference of the seal ring. The other end has a recess used in combination with the projection. The seal ring is characterized in that the recess has an inclining side face, which inclines from the direction of the circumference, and the projection and the recess form a sliding part so that a part of the edge of the leading end of the projection slides over the inclining side face of the recess, and portion of the sliding part is formed as a linear sliding portion.

Seal ring

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.

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

Yosuke Kondo