Eagle Industry Co., Ltd.

Nok Corporation

Other

Keiichi Chiba

Masatoshi Itadani

Yuichiro Tokunaga

Hideyuki Inoue

Kenji Kiryu

Hikaru Katori

Takeshi Hosoe

Kazumasa Sunagawa

Akira Yoshino

Wataru Kimura

Hiroshi Kubota

Yuta Negishi

Tetsuya Iguchi

Ryoma Yamakawa

Tetsuzo Okada

Hidetoshi Kasahara

Takafumi Ota

Tadahiro Kimura

Akiko Koga

Masahiro Kawaguchi

Masanori Sonobe

Takuya Okuno

Shinya Yamamoto

Atsuyuki Morishita

Yuki Sasaki

Satoshi Yasu

Kazumasa Sungawa

Wataru Kiura

Two conflicting functions of sealing and lubrication of sliding faces are achieved for a long time. The sliding face of a rotating-side seal ringis provided with dynamic pressure generation groovesconfigured to communicate with the circumferential edge on the inner peripheral side of the sliding face and not to communicate with the circumferential edge on the outer peripheral side. A springis provided on the back side of a stationary-side seal ringfor pressing the stationary-side seal ringagainst the sliding face of the rotating-side seal ring. A spring holderis provided between the back side of the stationary-side seal ringand the spring

Mechanical seal

In an exemplary embodiment, a mechanical seal for sealing a fluid flowing outwardly radially from sliding surfaces S where a stationary ringand a rotating ringslide against each other, includes: a bellowsinterposed between the stationary ringand a stationary wall; a case memberfor holding an outer cylindrical partof the bellowsto the stationary ring; and a holding memberfitted to an inner cylindrical partof the bellows, and having an axial length substantially equal to a length fitted to the inner cylindrical part, wherein the bellowshas a curved partbetween the outer cylindrical partand the inner cylindrical part, and the case memberis provided with a wall partcovering the entire periphery of the radial outer side of the curved part

In an exemplary embodiment, a sliding component includes an annular stationary side seal ringfixed to the stationary side and an annular rotating side seal ringto be rotated together with a rotating shaft, in which by relatively rotating opposing sealing faces S of the stationary side seal ringand the rotating side seal ring, a silicate-containing sealed fluid present on one side in the radial direction of the relatively rotating sealing faces S is sealed, wherein an amorphous carbon filmformed by using a hydrocarbon gas containing no silicon compound is provided on at least any one of the sealing faces S of the stationary side seal ringand the rotating side seal ring, and content of silicon of the amorphous carbon filmis 1.5 at % or less.

Sliding component

Both conflicting functions of sealing and lubrication of sliding faces are made compatible over an entire period from the time of startup through the time of steady operation. A pair of sliding parts that relatively slide on each other is provided, one of the sliding parts being a stationary-side seal ring, the other of the sliding parts being a rotating-side seal ring, the seal rings each having a sliding face S formed radially for sealing sealed fluid from leaking, at least one of the sliding faces S being provided with fluid introduction groovesconfigured to communicate with a first peripheral edge of the sliding face S and not to communicate with a second peripheral edge, and being provided with dynamic pressure generation grooves configured to communicate with the second peripheral edge of the sliding face S and not to communicate with the first peripheral edge.

Sliding component having fluid introduction groove and dynamic pressure generation groove

In an embodiment, in a sliding component, a sliding face of a stationary-side seal ringhas a fluid circulation groovecommunicating with a high-pressure fluid side via an entrance portionand an exit portion. A rotating-side seal ringhas a larger outer diameter and a smaller inner diameter than the seal ring. A grooveinto which a claw is loosely fitted is provided on an outer periphery of the seal ring. A width of the grooveis smaller than a distance between the portionand thein the circumferential direction. WMR/WSR is set within a range of 0.75&#x3c;WMR/WSR&#x3c;1.4 (WMR is a face width between an inner diameter of the grooveand an inner diameterof the sliding face; WSR is a face width of the sliding face).

A mechanical seal includes: a rotation-side member and a seal case positioned and fixed to each other, and in which the engaged state can be released by bringing the rotation-side member and the seal case closer to each other in the axial direction.

In an embodiments, in a sealing face of at least one slide part of a pair of slide parts, a dynamic pressure generation grooveis provided so as to be separated not to communicate with a sealed fluid side and a leakage side by land portions on both sealing faces, between an endon the leakage side of the dynamic pressure generation grooveand the leakage side, a fluid introduction groovewhich communicates the dynamic pressure generation grooveand the leakage side is provided, and the cross-sectional area of the fluid introduction grooveis set smaller than the cross-sectional area of the dynamic pressure generation groove. The sealing faces are subjected to fluid lubrication and low friction in a steady operation, and leakage of the sealed fluid and entrance of dust into the sealing faces are suppressed.

Slide component

A plain bearing () is fixed to a shaft hole () of an impeller () of the pump () so as to rotatably support the impeller () with respect to the shaft (), and is restricted from moving in an axial direction by an annular restrictor () fixed to the shaft (). On an end face () of the plain bearing () facing the restrictor (), a lubrication groove () connecting a radially inner side and a radially outer side of the end face () to supply cooling water onto the end face () for lubrication, and a dynamic pressure generating groove () that introduces a flow of cooling water created by rotation of the impeller () to generate a dynamic pressure, are provided. The present bearing suppresses an increase in rotation torque of the impeller () during high speed rotation.

Plain bearing and pump

In an embodiment, a pair of sliding components that slide relative to each other is included. One of the sliding components is a stationary-side seal ring, and the other sliding component is a rotating-side seal ring. The seal ringsandhave sliding faces Sand Sextending radially, respectively, for sealing sealed fluid against leakage. The sliding faces Sand Sare provided with a static pressure groovecommunicating with a sealing gas supply passage, and pumping groovescapable of controlling the radial flow of sealing gas to a flow from the low-pressure fluid side to the high-pressure fluid side by relative sliding of the sliding faces. By controlling the radial flow of sealing gas at the sliding face, the amount of flow of the sealing gas flowing to the low-pressure fluid side is reduced to improve sealing performance.

Sealing device

In an embodiment, in a slide component, a negative pressure generation mechanismthat generates negative pressure by relative rotational sliding of a stationary-side seal ringand a rotating-side seal ringis provided on a sealing face of one of the stationary-side seal ringand the rotating-side seal ring, and at least the surface of the negative pressure generation mechanismis covered by an adhesion-resistant material film. With the configuration, deposition of precipitates on a negative pressure portion of a sealing face can be inhibited.

In an embodiment, in a slide component, dynamic pressure generation groovesare provided on a sealing face of at least one of a pair of slide partsso as to be isolated with no communication from the sealed fluid side and the leakage side by land portions R of both the sealing faces, and a plurality of independently-formed minute recessed sectionsis provided at positions on the sealing face IS between the dynamic pressure generation groovesand the leakage side, the positions being separated in the radial direction from the dynamic pressure generation grooves. The slide component can make the sealing faces fluid-lubricant and low frictional and prevent leakage of a sealed fluid and incoming of dust to the sealing faces at the time of normal operation.

In an embodiment, a slide component includes one slide partprovided, on a low-pressure side of a sealing face thereof, with a negative pressure generation mechanismincluding a negative pressure generation groove. The negative pressure generation groovecommunicates with a high-pressure fluid side and is separated from a low-pressure fluid side by a land portion R. Another slide partis provided, in a sealing face thereof, with at least one interference groovecommunicating with the high-pressure fluid side for producing pressure variations in a fluid in the negative pressure generation groove. The at least one interference groovehas an endon an inside-diameter side extending to a position to radially overlap the negative pressure generation groove

In an embodiments, a slide component includes a pair of slide parts that relatively slide on each other, one of the slide parts being provided in a sealing face with fluid circulation groovesthat communicate with a high-pressure fluid side via inlet portions and outlet portions and are separated from a low-pressure fluid side by land portions, the other of the slide parts being circumferentially provided in a sealing face with a plurality of interference groovesfor producing pressure variations in a fluid in the fluid circulation grooves, adjacent ones of the interference groovesbeing set to have different shapes.

In an embodiment, a sliding face of at least one sliding part of the pair of sliding parts is provided, along its entire circumference, with a trap groovefor trapping leakage fluid, located on a leakage side and spaced from the leakage side by a land. A dust entry reduction meansfor reducing entry of dust from the leakage side while allowing passage of fluid is formed between lands of the pair of sliding parts on the leakage side of the trap groove. At the sliding faces of the pair of sliding parts sliding relatively, entry of dust from the leakage side as well as liquid leakage to the leakage side are suppressed.

In an embodiment, a sliding component includes a pair of sliding parts (a stationary-side seal ringand a rotating-side seal ring) that relatively slide on each other and each have a sliding face S formed radially for sealing sealed fluid from leaking. The sliding face S of at least one sliding part is provided with dynamic pressure generation groovesspaced in a non-communicating manner from the sealed-fluid side and the leakage side by lands R of both sliding faces, and is provided with fluid introduction holesbetween leakage-side endsof the groovesand the leakage side, for communicating the groovesand the leakage side. Each fluid introduction holesis configured such that a dynamic-pressure-generation-groove-side openingopen to a corresponding one of the groovesis axially displaced from a leakage-side openingopen to the leakage side.

Growing community of inventors

Tokyo, Japan

Keiichi Chiba