WO2022270697A1

WO2022270697A1 - Airfoil thrust bearing

Info

Publication number: WO2022270697A1
Application number: PCT/KR2021/018130
Authority: WO
Inventors: 임재만; 김경동
Original assignee: 주식회사 뉴로스
Priority date: 2020-09-11
Filing date: 2021-12-02
Publication date: 2022-12-29
Also published as: KR20220034647A; KR102590215B1

Abstract

The present invention relates to an airfoil thrust bearing comprising: a base plate; a bump foil which has uneven elastic bumps, and which is layered on the base plate such that one circumferential end portion thereof is coupled to the base plate; and a top foil which is layered thereon to cover the bump foil, and which has one circumferential end portion coupled to the base plate, wherein the bump foil is formed such that the height of the elastic bumps in a partial region adjacent to an outer diameter side in the radial direction is lower than the height of the elastic bumps in the remaining region, and thus the thrust bearing has higher durability since a primary damping friction part is separated from the region with the greatest energy loss according to the speed of a rotating body during excitation.

Description

air foil thrust bearing

The present invention relates to an air foil thrust bearing supporting an axial load acting on a rotating shaft in a turbo blower or a turbo compressor that compresses and supplies air by rotating an impeller at high speed using a rotational force of a motor.

A thrust bearing is used to support an axial load in a turbo blower or a turbo compressor. Among thrust bearings, air foil thrust bearings are mainly used to support the axial load of a rotating shaft rotating at high speed.

As shown in FIG. 1, a conventional air foil thrust bearing includes a base plate 10 formed of a donut-shaped plate, a plurality of bump foils 20 arranged spaced apart from each other along the circumferential direction, and disposed on each bump foil 20. It is composed of a plurality of top foils (30).

Here, the air foil thrust bearing is fixed by spot welding a plurality of bump foils 20 on the base plate 10, and after the top foil 30 is disposed on each bump foil 20, the base plate 10 ), the top foils 30 are fixed by spot welding. And when such an air foil thrust bearing is mounted and used in a turbo blower, a lot of frictional heat is generated due to contact between the disk-shaped thrust runner coupled to the rotating shaft and rotating together with the top foil of the air foil thrust bearing.

Here, in the conventional air foil thrust bearing, since the thrust runner, which is a rotating body, circularly moves, the angular velocity is the same, but the linear velocity according to the radial position gradually increases toward the outer diameter side. However, as the linear speed increases, the load bearing capacity by the air flowing between the top foil of the air foil thrust bearing and the rotating body increases, but high heat is generated due to friction between the air and the top foil, and the rotating body rotates at about 100,000 RPM In the case of the outer diameter side during high-speed rotation exceeding , high energy loss (heat generation) causes damage (heat scars) to the coating layer on the surface of the top foil. In addition, when excitation, friction first occurs in the top foil region corresponding to the place where the height of the elastic bump of the bump foil is the highest (main excitation support part). That is, as shown in FIG. 2, the conventional air foil journal bearing has a disadvantage in that durability is lowered because the area A1 with the highest energy loss and the main excitation support portion A2 partially overlap on the top foil 30.

[Prior art literature]

[Patent Literature]

KR 10-0954066 B1 (2010.04.13.)

The present invention has been made to solve the above-described problems, and an object of the present invention is to first support a load when excitation with a part having the largest energy loss according to the rotational speed of the rotating body, thereby causing damping friction in the first place. It is to provide an air foil thrust bearing capable of improving durability by separating the support portion.

An air foil thrust bearing of the present invention for achieving the above object includes a base plate; a bump foil formed with concavo-convex elastic bumps, stacked on the base plate, and having one end in a circumferential direction coupled to the base plate; and a top foil stacked to cover the bump foil and having one end in a circumferential direction coupled to the base plate. In the bump foil, a height of elastic bumps in a partial region adjacent to an outer diameter side in a radial direction may be lower than a height of elastic bumps in a remaining region.

In addition, the bump foil may be formed with slits penetrating both surfaces in the thickness direction while going along the circumferential direction from the free end.

In addition, elastic bumps corresponding to a partial area may be formed to have the same height from the free end, which is the other end in the circumferential direction, to one side of the bump foil on a specific radius.

And the air foil thrust bearing of the present invention includes a base plate; a bump foil formed with concavo-convex elastic bumps, stacked on the base plate, and having one end in a circumferential direction coupled to the base plate; a top foil stacked to cover the bump foil and having one end in a circumferential direction coupled to the base plate; and an insert plate interposed between the base plate and the bump foil in a portion corresponding to the remaining area except for a portion adjacent to the outer diameter side in the radial direction of the bump foil. It can be made including.

Also, among the elastic bumps disposed in the radial direction, the bump foils may have the same height as each other except for the insert plate.

And the air foil thrust bearing of the present invention includes a base plate; a bump foil formed with concavo-convex elastic bumps, stacked on the base plate, and having one end in a circumferential direction coupled to the base plate; and a top foil stacked to cover the bump foil and having one end in a circumferential direction coupled to the base plate. In the base plate, concave stepped grooves may be formed in a circumferential direction at a portion corresponding to the elastic bumps in a partial region adjacent to an outer diameter side in a radial direction of the bump foil.

Also, in the elastic bumps disposed in the radial direction, the bump foils may have the same height as each other.

In addition, the air foil thrust bearing of the present invention includes a bump foil plate in which a bump foil is integrally formed with a first plate and is connected to the first plate, and concavo-convex elastic bumps are formed on the bump foil plate; and a top foil plate having a top foil integrally formed with the second plate, the top foil connected to the second plate, and stacked on the bump foil plate such that the top foil covers the bump foil. In the bump foil, a height of elastic bumps in a partial region adjacent to an outer diameter side in a radial direction may be lower than a height of elastic bumps in a remaining region.

In addition, the bump foil of the bump foil plate is composed of a plurality, each of the plurality of bump foils has one end connected to the first plate in a circumferential direction, and the plurality of bump foils are arranged spaced apart from each other along the circumferential direction, The top foil of the top foil plate is composed of a plurality, and each of the plurality of top foils has one end connected to the second plate in a circumferential direction, and the plurality of top foils are spaced apart from each other along the circumferential direction to form the plurality of bump foils. It can be arranged in a position corresponding to.

An insert plate stacked on a surface opposite to the bump foil plate on which the top foil plate is stacked and disposed in a portion corresponding to an area other than a portion adjacent to an outer diameter side in a radial direction of the bump foil, The height of the elastic bumps in a partial area adjacent to the outer diameter in the radial direction may be lower than the height of the elastic bumps in the remaining area by the insert plate.

The top foil plate may further include a bearing housing stacked on a surface opposite to the bump foil plate on which the top foil plate is stacked, wherein the bearing housing corresponds to elastic bumps in a partial area adjacent to an outer diameter side of the bump foil in a radial direction. A concave stepped groove is formed in the circumferential direction, and the height of the elastic bumps in a partial region adjacent to the outer diameter in the radial direction may be lower than the height of the elastic bumps in the remaining region by the stepped groove of the bearing housing.

In addition, the elastic bumps of the bump foil may be formed to have the same height as each other in the elastic bumps disposed in the radial direction.

The air foil thrust bearing of the present invention has the advantage of having higher durability because the primary damping friction part is separated from the region where the energy loss according to the speed of the rotating body is the greatest and when it is excited.

1 is a perspective view showing a conventional air foil thrust bearing.

2 is a partial plan view showing an area with the greatest energy loss and a main excitation support in a conventional air foil thrust bearing.

3 to 5 are an exploded perspective view, an assembled perspective view, and an upper plan view showing an air foil thrust bearing according to a first embodiment of the present invention.

6 and 7 are A-A' cross-sectional views and B-B' cross-sectional views of FIG.

FIG. 8 is a cross-sectional view showing a state in which a part of the top foil is elastically deformed when the thrust runner, which is a rotation body, in the cross section of FIG. 7 is in contact with the top foil in a state of being rotated at high speed.

9 is a perspective view showing an embodiment of a bump foil in an air foil thrust bearing according to a first embodiment of the present invention.

10 is a cross-sectional view showing a portion of an air foil thrust bearing cut in a radial direction according to a second embodiment of the present invention.

11 is a cross-sectional view showing a portion of an air foil thrust bearing cut in a radial direction according to a third embodiment of the present invention.

12 is a plan view showing a bump foil in an air foil thrust bearing according to the present invention.

13 to 15 are an exploded perspective view, an assembled perspective view, and an upper plan view showing an air foil thrust bearing according to a fourth embodiment of the present invention.

16 is a C-C′ cross-sectional view of FIG. 15;

17 is a cross-sectional view showing a portion of an air foil thrust bearing cut in a radial direction according to a fifth embodiment of the present invention.

18 is a cross-sectional view showing a portion of an air foil thrust bearing cut in a radial direction according to a sixth embodiment of the present invention.

Hereinafter, the air foil thrust bearing of the present invention as described above will be described in detail with reference to the accompanying drawings.

3 to 5 are an exploded perspective view, an assembled perspective view, and an upper plan view showing an air foil thrust bearing according to a first embodiment of the present invention, and FIGS. 6 and 7 are A-A' cross-sectional views and B-B' cross-sectional views of FIG.

As shown, the air foil thrust bearing according to the first embodiment of the present invention may be largely composed of a base plate 100, a bump foil 200, and a top foil 300.

The base plate 100 may be formed in a disk shape in which a hollow hole penetrating both sides in a thickness direction is formed at a central portion.

A plurality of bump foils 200 may be arranged spaced apart from each other along the circumferential direction. In addition, each of the bump foils 200 may be fixed by welding only one end portion 210 in the circumferential direction to the base plate 100, and the other end portion in the circumferential direction may be formed as a free end. In addition, the bump foils 200 may have concavo-convex elastic bumps 220 formed therein, and the elastic bumps 220 may be separated from each other without being fixed even though their lower ends are in contact with the base plate 100 . That is, the rest of the bump foil 200 except for the coupling portion 210 may be in a state where it is not coupled to the base plate 100 and is separated, and the elastic bumps 220 are in contact with the base plate 100. or there may be a slight gap.

A plurality of top foils 300 may be arranged spaced apart from each other along the circumferential direction. In addition, each of the top foils 300 may be fixed by welding only one end portion 310 in the circumferential direction to the base plate 100, and the other end portion in the circumferential direction may be formed as a free end. In this case, the top foils 300 may be disposed at positions corresponding to the bump foils 200 and stacked in such a way that the top foils 300 cover the bump foils 200 . That is, the bump foil 200 may be interposed between the base plate 100 and the top foil 300 . In addition, when looking at a cross section cut along the circumferential direction on a specific radius as shown in FIG. 5, in the top foil 300, the connecting portion 320 extends upward in a curved or flat shape from the coupling portion 310 along the circumferential direction. , and a flat portion 330 extending from the connecting portion 320 may be formed parallel to the base plate 100 . In addition, the bump foil 200 corresponds to a partial area in one direction from the free end, which is the other end in the circumferential direction, on a specific radius, that is, the elastic bumps 220 corresponding to the flat portion 330 of the top foil 300 have a mutual height. The elastic bumps 220 in an area corresponding to the connecting portion 320 of the top foil 300 may be formed to have a relatively low height. There may be a space between the lower surface of the connection part 320 and the mountains of the elastic bumps 220 .

Here, referring to FIG. 7 , when a cross section of the top foil 300 cut in the radial direction at the portion where the flat portion 330 is located, the bump foil 200 has elastic bumps in a partial area adjacent to the outer diameter side in the radial direction. The height h4 of 220 may be lower than the heights h1 , h2 , and h3 of the elastic bumps 220 in the remaining regions, that is, the region adjacent to the inner diameter in the radial direction and the central region. At this time, one elastic bump radially adjacent to the outer diameter (on the right side) is the outer diameter side elastic bump, the other elastic bump radially adjacent to the inner diameter (left side) is the inner diameter side elastic bump, and the other elastic bump located at the center in the radial direction is the outer elastic bump. If the two elastic bumps are referred to as central elastic bumps, the top foil 300 may come into contact with the inner diameter side elastic bumps and the center elastic bumps in a state where no external force such as air pressure acts, and in this state, the outer diameter side elasticity. The peak of the bump may be spaced apart from the top foil 300 due to the height difference Δh.

Thus, when looking at the cross section of the air foil thrust bearing cut in the radial direction as shown in FIG. 8, the thrust runner 400, which is a rotating body, rotates at high speed due to an axial load or excitation, and the top foil ( 300), the top foil 300 in the area corresponding to the portion where the outer diameter-side elastic bump is located is bent toward the elastic bump by the pressure of the air flowing between the thrust runner 400 and the top foil 300. It may not come into contact with the thrust runner 400 . That is, in the area adjacent to the outer diameter in the radial direction, the linear velocity is relatively fast, and the energy loss (heat generation) due to friction with air is relatively large. And the top foil 300 can be in direct contact with damping and rubbing. And when the thrust runner 400 comes into contact with the top foil 300 due to excitation, etc., it first contacts the flat surface 330 of the top foil 300, and damping and friction occur primarily. As shown, the bump foil The flat part 330 of the top foil 300 corresponding to the area where the elastic bumps on the inner diameter side of 200 and the elastic bumps in the center exist is the main excitation support that primarily supports the load of the thrust runner 400. do.

Accordingly, the air foil thrust bearing of the present invention can have higher durability because the primary damping friction part does not overlap with the region where the energy loss according to the speed of the rotating body is the greatest and is formed at different positions. In addition, since the direct friction between the thrust runner and the top foil is reduced in the outer diameter side, which is the area where energy loss is greatest, there is an effect that damage (heat marks) to the coating layer coated on the surface of the top foil may not occur.

As shown, the bump foil 200 may have slits 230 penetrating both surfaces in the thickness direction while going along the circumferential direction from the free end. That is, for example, a region where the elastic bumps 220 of the bump foil 200 are formed by the slits 230 may be divided into three parts in a radial direction. At this time, the three parts may be in a state of being connected to each other by one end of the coupling part 210.

As shown, the air foil thrust bearing according to the second embodiment of the present invention may be largely composed of a base plate 100, a bump foil 200, a top foil 300, and an insert plate 150. Here, the base plate 100 and the top foil 300 may be formed in the same manner as in the first embodiment described above. Also, the bump foil 200 may have the same height as the elastic bumps 220 arranged in the radial direction, and the configuration of the rest of the bump foil 200 may be identical to that of the first embodiment described above. there is. The insert plate 150 may be formed in a thin flat plate shape and interposed between the base plate 100 and the bump foil 200 . In this case, the insert plate 150 may be disposed in a region where the inner diameter elastic bumps 220 and the center elastic bumps 220 exist in the radial direction. Thus, as a result of the insert plate 150, the heights of the inner diameter-side elastic bumps 220 and the center elastic bumps 220 are relatively higher with respect to the upper surface of the base plate 100, and compared to this, the outer diameter-side elastic bumps 220 ) is relatively low.

Accordingly, a height difference Δh between the elastic bumps may be formed using the insert plate, and the degree of the height difference may be easily adjusted. And, like the first embodiment, the durability of the air foil thrust bearing can be improved.

As shown, the air foil thrust bearing according to the third embodiment of the present invention may be largely composed of a base plate 100, a bump foil 200, and a top foil 300. Here, the top foil 300 may be formed in the same manner as in the first embodiment described above. Also, the bump foil 200 may have the same height as the elastic bumps 220 arranged in the radial direction, and the configuration of the rest of the bump foil 200 may be identical to that of the first embodiment described above. there is. The overall shape of the base plate 100 is the same as that of the first embodiment, and only the stepped grooves may be formed with a difference. That is, the stepped groove 110 may be concavely formed along the circumferential direction on the upper surface of the base plate 100 at a portion corresponding to the outer diameter-side elastic bump 220 of the bump foil 200 . Thus, the outer diameter-side elastic bump 220 may be inserted into the stepped groove 110 of the base plate 100 and placed therein. Thus, as a result of the stepped groove 110 of the base plate 100, the heights of the inner diameter-side elastic bumps and the central part elastic bumps are relatively higher with respect to the upper surface of the base plate 100, and the outer diameter-side elastic bumps have a height of becomes relatively low.

Accordingly, the height difference Δh between the elastic bumps can be formed using the stepped groove of the base plate, and the height difference can be formed without a separate additional part. And, like the first embodiment, the durability of the air foil thrust bearing can be improved.

In addition, as an example, when looking at the elastic bumps 220 in the bump foil 200 as shown in FIG. 12, the height of the elastic bump from the lower surface of the base plate to the crest of the elastic bump d1 is higher than the height of the central elastic bump d1. The heights of (c2, d2, e2, f2) may be formed low. Here, the height difference between the elastic bumps may be in the range of 0.01 mm to 0.2 mm, and if the height difference between the elastic bumps is less than 0.01 mm, the effect of the present invention may not appear, and if the height difference is greater than 0.2 mm, high heat may be generated.

13 to 15 are an exploded perspective view, an assembled perspective view, and an upper plan view showing an air foil thrust bearing according to a fourth embodiment of the present invention, and FIG. 16 is a C-C' of an air foil thrust bearing according to a fourth embodiment of the present invention. it is a cross section

As shown, the air foil thrust bearing according to the fourth embodiment of the present invention may be largely composed of a bump foil plate 500 and a top foil plate 600.

The bump foil plate 500 may include a first plate 510 and a plurality of bump foils 520, and may be formed in a form in which the first plate 510 and each bump foil 520 are integrally connected. there is. In addition, the bump foils 520 may be arranged spaced apart from each other along the circumferential direction, and each end of the bump foils 520 is connected to the first plate 510, and the rest except for the connected end is connected to the first plate ( 510) and may be spaced apart. That is, only one end of the bump foils 520 in the circumferential direction is connected to the first plate 510 , and inner and outer ends in the circumferential direction are not connected to the first plate 510 and may be separated from each other. In addition, the bump foil 520 may be formed in a corrugated or wavy shape by forming concavo-convex elastic bumps 522, and the elastic bumps 522 protrude upward from the upper surface of the first plate 510. The bump foil 520 may be formed in a shape having a shape. In addition, the bump foils 520 may be formed with slits 523 penetrating both surfaces in the thickness direction while going along the circumferential direction from the free end. That is, for example, a region in which the elastic bumps 522 of the bump foil 520 are formed by the slits 523 may be divided into three parts in a radial direction. At this time, one end of the three parts may be connected to the first plate 510 .

The top foil plate 600 may include a second plate 610 and a plurality of top foils 620, and may be formed in a form in which the second plate 610 and each top foil 620 are integrally connected. there is. In addition, the top foils 620 may be arranged spaced apart from each other along the circumferential direction, and one end in the circumferential direction may be connected to the second plate 610 and the rest of the top foils 620 may be spaced apart from the second plate 610. there is. That is, only one end of the top foils 620 in the circumferential direction is connected to the second plate 610, and the inner and outer ends in the circumferential direction are not connected to the second plate 610 but may be separated. In addition, the top foils 620 are convexly extended from the point connected to the second plate 610 in the circumferential direction, and at the end of the connection portion 621, a plane parallel to the second plate 610 is formed. The portion 622 may be formed in an extended form.

Thus, the surface of the bump foil plate 500 on which the elastic bumps 522 of the bump foil 520 protrude and the opposite surface of the top foil plate 600 on which the connection portion 621 of the top foil 620 protrudes is formed. They may be stacked facing each other to form one air foil thrust bearing. In addition, the air foil thrust bearing of the present invention may be coupled so that the opposite surface of the bump foil plate 500 facing the top foil plate 600 is in contact with the bearing housing 800 to be supported. Here, the bearing housing 800 may be a part where an air foil thrust bearing is placed and mounted in a turbo blower or an air compressor. Also, in the fourth embodiment of the present invention, as in the first embodiment, when a cross section of the top foil 620 cut in the radial direction at the portion where the flat portion 622 is located, the bump foil 520 is radially toward the outer diameter. The height h4 of the elastic bumps 522 in the adjacent partial region may be lower than the heights h1, h2, and h3 of the elastic bumps 522 in the central region and the region adjacent to the inner diameter in the radial direction, which is the remaining region. At this time, one elastic bump radially adjacent to the outer diameter (on the right side) is the outer diameter side elastic bump, the other elastic bump radially adjacent to the inner diameter (left side) is the inner diameter side elastic bump, and the other elastic bump located at the center in the radial direction is the outer elastic bump. If the two elastic bumps are referred to as central elastic bumps, the top foil 620 may come into contact with the inner diameter side elastic bumps and the center elastic bumps in a state where no external force such as air pressure acts, and in this state, the outer diameter side elasticity The peak of the bump may be spaced apart from the top foil 620 due to the height difference Δh.

Thus, like the first embodiment of the present invention, when the thrust runner, which is a rotating body, is in contact with the top foil due to an axial load or excitation in a state where the thrust runner is rotated at high speed, the air flowing between the thrust runner and the top foil The top foil 620 in the area corresponding to the portion where the outer diameter-side elastic bump is located may be bent toward the elastic bump 522 by the pressure of the outer diameter side and may not come into contact with the thrust runner. That is, in the area adjacent to the outer diameter in the radial direction, the linear speed is relatively high, so the energy loss (heat) due to friction with air is relatively large. 620 can be damped and rubbed in direct contact. And when the thrust runner comes into contact with the top foil 620 due to excitation, etc., it first contacts the flat surface 622 of the top foil 620, and damping and friction occur primarily. As shown, the bump foil 520 The flat portion 622 of the top foil 620 corresponding to the area where the elastic bumps on the inner diameter side and the elastic bumps exist in the central portion of the inner diameter side of the inner diameter side and the flat portion 622 of the top foil 620 primarily serves as a main supporting portion for supporting the load of the thrust runner.

As shown, the air foil thrust bearing according to the fifth embodiment of the present invention may largely include a bump foil plate 500, a top foil plate 600, and an insert plate 700. Here, the top foil plate 600 may be formed in the same manner as in the fourth embodiment described above. Also, the bump foil plate 500 may have the same height as the elastic bumps 220 arranged in the radial direction, and the rest of the first plate 510 and the bump foils 520 may have the same configuration as the fourth described above. It may be formed in the same way as in the embodiment. The insert plate 700 may be formed in a thin flat plate shape, and the insert plate 700 may be stacked on a surface opposite to the bump foil plate 500 on which the top foil plate 600 is stacked. Thus, when the bearing housing 800 exists, it may be interposed between the bearing housing 800 and the bump foil plate 500 . Also, the insert plate 700 may be disposed in a portion corresponding to the rest of the bump foil 520 except for a portion adjacent to the outer diameter side in the radial direction. That is, the insert plate 700 may be disposed in a region where the inner diameter side elastic bumps 522 and the center elastic bumps 522 exist in the radial direction. Thus, as a result of the insert plate 700, the heights of the inner diameter side elastic bumps 522 and the center part elastic bumps 522 are relatively high with respect to the upper surface of the bearing housing 800, and compared to this, the outer diameter side elastic bumps 522 ) is relatively low.

Accordingly, the height difference Δh between the elastic bumps can be formed using the insert plate, the degree of the height difference can be easily adjusted, and durability of the air foil thrust bearing can be improved.

As shown, the air foil thrust bearing according to the sixth embodiment of the present invention may largely include a bump foil plate 500, a top foil plate 600, and a bearing housing 800. Here, the top foil plate 600 may be formed in the same manner as in the fourth embodiment described above. In addition, the bump foil plate 500 may have the same height as the elastic bumps 522 disposed in the radial direction, and the configuration of the other bump foils 520 may be identical to those of the fourth embodiment. can In the bearing housing 800 , a stepped groove 810 may be concavely formed along the circumferential direction on an upper surface of the bearing housing 800 at a portion corresponding to the outer diameter-side elastic bump 522 of the bump foil plate 500 . Thus, the outer diameter-side elastic bump 522 may be inserted into the stepped groove 810 of the bearing housing 800 and placed therein. Therefore, as a result of the stepped groove 810 of the bearing housing 800, the inner diameter side elastic bumps and the center elastic bumps have a relatively high height with respect to the upper surface of the bearing housing 800, and the outer diameter side elastic bumps have a relatively high height. becomes relatively low.

Accordingly, the height difference (Δh) between the elastic bumps can be formed using the stepped groove of the bearing housing, and the height difference can be formed without additional parts, and durability of the air foil thrust bearing can be improved.

In addition, the height difference between the elastic bumps may be in the range of 0.01 mm to 0.2 mm, and if the height difference between the elastic bumps is less than 0.01 mm, the effect of the present invention may not appear, and if the height difference is greater than 0.2 mm, high heat may be generated.

The present invention is not limited to the above embodiments, and the scope of application is diverse, and anyone with ordinary knowledge in the field to which the present invention belongs without departing from the gist of the present invention claimed in the claims Of course, various modifications are possible.

[Description of code]

100: base plate, 110: stepped groove

150: insert plate, 200: bump foil

210: coupling part, 220: elastic bump

230: slit, 300: top foil

310: coupling part, 320: connection part

330: flat part, 400: thrust runner

500: bump foil plate, 510: first plate

520: bump foil, 522: elastic bump

523: slit, 600: top foil plate

610: second plate, 620: top foil

621: connection part, 622: flat part

700: insert plate, 800: bearing housing

810: stepped home

Claims

base plate;

a bump foil formed with concavo-convex elastic bumps, stacked on the base plate, and having one end in a circumferential direction coupled to the base plate; and

a top foil stacked to cover the bump foil and having one end in a circumferential direction coupled to the base plate; including,

The bump foil,

An air foil thrust bearing, characterized in that the height of elastic bumps in a partial region adjacent to the outer diameter side in the radial direction is lower than the height of elastic bumps in other regions.
According to claim 1,

The air foil thrust bearing, characterized in that the bump foil is formed with a slit penetrating both sides in the thickness direction while going along the circumferential direction from the free end.
base plate;

a bump foil formed with concavo-convex elastic bumps, stacked on the base plate, and having one end in a circumferential direction coupled to the base plate;

a top foil stacked to cover the bump foil and having one end in a circumferential direction coupled to the base plate; and

an insert plate interposed between the base plate and the bump foil at a portion corresponding to the remaining area except for a portion adjacent to the outer diameter side of the bump foil in a radial direction;

An air foil thrust bearing comprising a.
According to claim 3,

The air foil thrust bearing, characterized in that the bump foil is formed with a slit penetrating both sides in the thickness direction while going along the circumferential direction from the free end.
According to claim 3,

The bump foil,

In the elastic bumps disposed in the radial direction, the elastic bumps themselves except for the insert plate have the same height as each other.
base plate;

a bump foil formed with concavo-convex elastic bumps, stacked on the base plate, and having one end in a circumferential direction coupled to the base plate; and

a top foil stacked to cover the bump foil and having one end in a circumferential direction coupled to the base plate; including,

The base plate,

An air foil thrust bearing, characterized in that a concave stepped groove is formed along the circumferential direction in a portion corresponding to the elastic bumps in a partial area adjacent to the outer diameter side in the radial direction of the bump foil.
According to claim 6,

The air foil thrust bearing, characterized in that the bump foil is formed with a slit penetrating both sides in the thickness direction while going along the circumferential direction from the free end.
According to claim 6,

The bump foil is an air foil thrust bearing, characterized in that the height of the elastic bumps corresponding to a partial area from the free end of the other end in the circumferential direction to one side is formed to be the same on a specific radius.
According to claim 6,

The bump foil,

An air foil thrust bearing, characterized in that in the elastic bumps disposed in the radial direction, the elastic bumps themselves have the same height.
a bump foil plate in which a bump foil is integrally formed with a first plate and is connected to the first plate, and concavo-convex elastic bumps are formed on the bump foil; and

a top foil plate having a top foil integrally formed with a second plate, the top foil connected to the second plate, and stacked on the bump foil plate such that the top foil covers the bump foil; including,

The bump foil,

An air foil thrust bearing, characterized in that the height of elastic bumps in a partial region adjacent to the outer diameter side in the radial direction is lower than the height of elastic bumps in other regions.
According to claim 10,

The bump foil of the bump foil plate is composed of a plurality, each of the plurality of bump foils has one end connected to the first plate in a circumferential direction, and the plurality of bump foils are arranged spaced apart from each other along the circumferential direction,

The top foil of the top foil plate is composed of a plurality, and each of the plurality of top foils has one end connected to the second plate in a circumferential direction, and the plurality of top foils are spaced apart from each other along the circumferential direction to form the plurality of bump foils. Air foil thrust bearing, characterized in that arranged in a position corresponding to.
According to claim 11,

The air foil thrust bearing, characterized in that the bump foil is formed with a slit penetrating both sides in the thickness direction while going along the circumferential direction from the free end.
According to claim 11,

An insert plate stacked on a surface opposite to the bump foil plate on which the top foil plate is stacked and disposed in a portion corresponding to a remaining area except for a portion adjacent to an outer diameter side in a radial direction of the bump foil,

The air foil thrust bearing according to claim 1 , wherein the height of the elastic bumps in a partial area adjacent to the outer diameter side in the radial direction is formed lower than the height of the elastic bumps in the remaining area by the insert plate.
According to claim 13,

The bump foil,

An air foil thrust bearing, characterized in that in the elastic bumps disposed in the radial direction, the elastic bumps themselves have the same height.
According to claim 11,

Further comprising a bearing housing laminated on a surface opposite to the bump foil plate on which the top foil plate is laminated,

The bearing housing,

Concave stepped grooves are formed along the circumferential direction in a portion corresponding to the elastic bumps in a partial area adjacent to the outer diameter side in the radial direction of the bump foil,

An air foil thrust bearing, characterized in that the height of elastic bumps in a partial area adjacent to the outer diameter side in the radial direction is formed lower than the height of elastic bumps in the remaining area by the stepped groove of the bearing housing.
According to claim 15,

The bump foil,

An air foil thrust bearing, characterized in that in the elastic bumps disposed in the radial direction, the elastic bumps themselves have the same height.