Ntn Corporation

Masato Yoshino

Hiroki Fujiwara

Yuushi Onda

Mitsuo Kawamura

Kazuyoshi Harada

Yohei Yamamoto

Masatsugu Mori

Kikuo Fukada

Naoya Okamoto

Jun Midoumae

Miki Okamoto

Each of foils () includes: a top foil portion () including a bearing surface (S); and a back foil portion (), which is formed on an upstream side of the top foil portion (), and is arranged so as to overlap behind the top foil portion () of the adjacent foil () (on a side opposite to the bearing surface (S)). An angle (E) covering a radially inner end of an overlapping portion (P) between the adjacent foils () is smaller than an angle (D) covering a radially outer end of the overlapping portion (P).

Thrust foil bearing, foil bearing unit, turbo machine, and foil

A thrust foil bearinghaving a thrust bearing surface S formed by arranging a plurality of leavesside by side in a circumferential direction, in which each of the leaveshas a top foil portion Tf that forms the thrust bearing surface S, and a ratio of a circumferential length A of the top foil portion Tf of one of the leavesat a radially central position of the top foil portion Tf, to a radial length B from an inner diameter-side edgeto an outer diameter-side edgeof the top foil portion Tf is 0.66 or less.

Thrust foil bearing

A thrust foil bearing includes a thrust member, and a foil member mounted to an end surface of the thrust member and having a thrust bearing surface that forms a thrust bearing gap. The foil member includes a foil that integrally includes a plurality of leaves each having a free end on one side in a circumferential direction and the thrust bearing surface, and a coupling portion for coupling the plurality of leaves to each other.

The present invention provides a foil bearing (), including: a top foil portion (Tf); and a back foil portion (Bf), which is arranged on a back of the top foil portion (Tf), and is configured to elastically support the top foil portion (Tf), wherein the back foil portion (Bf) includes: an intermediate portion () being flat; first projecting portions () projecting on a front side of the intermediate portion (); and second projecting portions () projecting on a back side of the intermediate portion ().

Foil bearing

Particles () are supplied to a bearing gap of a foil bearing. A step () is formed in a top foil portion (), to thereby generate an air flow from both end portions (and) in a direction (N) along a surface of the top foil portion () and orthogonal to a rotation direction (R) of a shaft () toward a region between the both end portions.

Provided is a cooling structure for a bearing device. The bearing device includes a rolling bearing having a stationary raceway ring and a rotating raceway ring, a stationary spacer adjacent to the stationary raceway ring and a rotating spacer adjacent to the rotating raceway ring. The stationary raceway ring and the stationary spacer are provided in a stationary member, and the rotating raceway ring and the rotating spacer are provided in a rotating member. The cooling structure includes: an annular recessed portion provided on a circumferential surface, of the stationary spacer, that confronts an opposite spacer; and a nozzle hole configured to inject a compressed air from an outlet open to a bottom surface of the recessed portion toward a circumferential surface of the rotating spacer that confronts an opposite spacer. The nozzle hole is inclined forwardly in a rotation direction of the rotating spacer.

Cooling structure for bearing device

A foil bearing () includes foils () at a plurality of portions in a rotation direction of a shaft member (). A top foil portion (Tf) including a bearing surface (S) is formed in a region including a front end () of each of the foils (), and a back foil portion (Bf) is formed in a region including a rear end () of each of the foils (). A gap (C) is secured between, of two of the foils adjacent to the foil () in a rotation direction (R) and a direction opposite to the rotation direction, the rear end () of the foil on the rotation direction side and the front end () of the foil on the side opposite to the rotation direction side. A width of the gap (C) is set to be non-uniform in a direction (N) orthogonal to the rotation direction.

Foil bearing, production method therefor, and intermediate product of foil bearing

A foil bearing includes a foil holder and a plurality of foils fixed to the foil holder and arrayed in a circumferential direction. Each of the foils includes a top foil portion having a bearing surface, an extending portion formed on one circumferential side of the top foil portion, an underfoil portion formed on another circumferential side of the top foil portion, and an insertion slot formed between the top foil portion and the underfoil portion in the circumferential direction. The insertion slot includes a positioning portion and a wide portion that is larger in circumferential width than the positioning portion and is opened to an end portion of each of the foils. An edge of the top foil portion, which is opposed to the wide portion, retreats toward the one circumferential side with respect to an edge opposed to the positioning portion.

A thrust foil bearing () includes a foil holder () and a plurality of foils (). Each of the foils () includes: a top foil portion (); an extending portion (); and an underfoil portion (). The extending portion () of the each of the foils () is arranged behind another of the foils () that is adjacent to the each of the foils () on the one circumferential side. The underfoil portion () of the each of the foils () is arranged between the top foil portion () of the another of the foils (), which is adjacent to the each of the foils () on another circumferential side, and the end surface () of the foil holder ().

A bearing device includes a rolling bearing having an outer ring and an inner ring, an outer ring spacer disposed adjacent to the outer ring, and an inner spacer disposed adjacent the inner ring. The outer ring and the outer ring spacer are fitted to a housing, and the inner ring and the inner ring spacer are fitted to a rotary shaft. The outer ring spacer is provided with a nozzle, which is configured to inject a cooling fluid (R) toward an outer circumferential surface of the inner ring, and is inclined so that an injection port thereof is inclined forwardly in a rotation direction of the inner ring. An inclination angle &#x3b1; of the nozzle with respect to an axial direction is set to a value within a range from 50&#xb0; to 90&#xb0;.

A foil bearing includes: a tubular foil holder (); and a plurality of foils () having a radial bearing surface (S) and being arrayed on an inner peripheral surface () of the foil holder () in a circumferential direction. Both circumferential ends (projecting portions () and projecting portion ()) of each of the foils () are held on the foil holder (). The foil bearing is configured to support a shaft () inserted along an inner periphery thereof in a freely rotatable manner. The plurality of foils () are held on the foil holder () under a circumferentially movable state.

Foil bearing, and foil bearing unit and turbo machine each having same

A rolling bearing includes an inner ring and an outer ring which are bearing rings; a plurality of rolling elements interposed in a rollable manner between raceway surfaces of the bearing rings; and a retainer configured to retain the plurality of rolling elements. Nozzles configured to inject a cooling fluid (R) toward the rolling elements are provided to a fixed-side bearing ring which is one of the inner ring and the outer ring, with an outlet side of each of the nozzles oriented forward in a revolution direction of the rolling elements.

Rolling bearing

A foil bearing (thrust foil bearing ()) includes a foil holder () and a plurality of foils () arrayed in a circumferential direction. Each of the foils () includes a body portion () having a thrust bearing surface (S) and an extended portion () extending from the body portion () to a radially outer side. An end portion () of the body portion () of each of the foils () on one circumferential side is arranged so as to be overlapped on the body portion () of adjacent one of the foils (). The extended portions () of the plurality of foils () are fixed onto the same plane of the foil holder ().

Foil bearing and method for manufacturing thereof

Provided is a foil bearing, an air film is formed in a radial bearing gap between a first bearing surface arranged on a top foil and a second bearing surface along with rotation of a shaft, and the shaft is supported with a pressure of the air film. Lubricating powder is interposed between the bearing surfaces. The top foil is partially elastically deformed in a width direction of the radial bearing gap in accordance with the pressure of the air film generated in the radial bearing gap, thereby being alternately shifted between a first state in which a retaining portion capable of retaining the lubricating powder is formed and a second state in which the retaining portion substantially disappears, and shifted from the second state to the first state along with an increase in the pressure of the air film.

A foil bearing includes an outer member (), and a plurality of foils () that are mounted to an inner circumferential surface () of the outer member () and directly face the inner circumferential surface () of the outer member () in a radial direction without interposition of another member (such as back foils). The foils () each include: holding portions () that are formed at both circumferential ends and held while in contact with the outer member (); and a body portion () that is formed circumferentially between the holding portions () and has a bearing surface (A). At least an end portion on one side in a circumferential direction of the body portion () is raised radially inward with respect to the inner circumferential surface () of the outer member ().

Growing community of inventors

Mie, Japan

Masato Yoshino