JPH07305721A - Self-aligning thrust sliding bearing - Google Patents

Abstract

PURPOSE:To make it possible to rotate a thrust sliding bearing in the condition that the bearing receives the thrust load even in the case where the shaft center is much inclined. CONSTITUTION:A shaft side sliding body 2 having the spherically convex sliding surface is fitted to the lower part of a rotary shaft 1, and the shaft side sliding body 2 is slid for rotation with a bearing main body 3 having the spherically concave sliding surface. The bearing main body 3 is provided with plural hydrostatic pockets 4, and the lubricating oil is supplied from a hydraulic pump 7 to the hydrostatic pockets 4 through a throttle 5 and a hydraulic pipeline 6. Even in the case where the rotary shaft 1 is much inclined in relation to the shaft center, the sliding surfaces make contact with each other in a spherically convex shape and a spherically concave surface and the shaft can be smoothly rotated, receiving the thrust load, by the action of the lubricating oil.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a self-aligning thrust slide bearing applied to a rotor support bearing used in a vertical shaft type rotary regenerative air preheater.

[0002]

11 is a sectional view of a conventional self-aligning thrust plain bearing, FIG. 12 is a view taken along the arrow DD in FIG. 11, which shows a portion below the bearing pad, and FIG. 13 is a development of a circumferential section in FIG. It is the figure which exaggerated and showed the oil-film formation state in the figure. In these figures, 11 is a rotary shaft, and a shaft side sliding plate 12 is attached to the lower part. 13 is a shaft side sliding plate 12
13 are bearing pads that slide in contact with the lower part of the sliding plate 12, and a plurality of bearing pads are arranged on the circumferential lower surface of the sliding plate 12 as shown in FIG. Reference numeral 14 is a pivot attached to the lower portion of the bearing pad 13, which allows the bearing pad to be tilted around the support point on the upper leveling plate 16. Reference numeral 17 denotes a plurality of lower leveling plates which support the upper leveling plate 16 and are tiltably arranged on the bearing support plate 15.

In the conventional thrust slide bearing having such a structure, the rotation of the rotary shaft 11 slides between the sliding plate 12 on the shaft side and the bearing pad 13 by forming an oil film 20 as shown in FIG. Although it functions as a slide bearing, it is composed of a plurality of flat bearing pads 13 arranged on the circumference and upper and lower leveling plates 16 and 17, and is locally generated on the rotating slip surface due to the inclination of the shaft center. It has a leveling mechanism for distributing the concentrated load to the adjacent plain bearing pads 13.

[0004]

In the conventional thrust slide bearing, as shown in FIGS. 11 to 13, the local concentrated load generated by the inclination of the shaft center is one flat bearing pad 1.
In order to distribute the localized concentrated load to a plurality of adjacent pads so that problems such as seizure do not occur,
It has a leveling mechanism in which the lower leveling plates 16 and 17 are arranged in combination. In such a structure, since the shaft center is tilted due to the complicated configuration of the leveling plates 16 and 17, the allowable tilt angle of the shaft center is small (usually about 2
0'≈0.3). Also, if the shaft center is tilted beyond this, the load does not act evenly on the flat bearing pads around the entire circumference, and local concentrated loads act only on some flat bearing pads, causing problems such as seizure. Therefore, it cannot be used as a bearing when a large inclination angle occurs.

Further, in the conventional structure, as described above, the structure for receiving the bearing pad 13 is a complicated mechanism in which a plurality of upper leveling plates 16 and lower leveling plates 17 are combined on the circumference, so that the structure is manufactured. It has been strongly desired to realize a plain bearing which has a high cost and a simple structure which can be manufactured at low cost.

In order to solve such a problem, the present invention makes the shaft-side sliding surface of the rotating shaft spherical and the bearing main body which receives the shaft-side sliding surface also spherical concave, in which the lubricating oil is introduced. The purpose of the present invention is to provide a self-aligning thrust bearing which has a simple structure which can easily receive the thrust load even when the shaft center is largely inclined.

[0007]

Therefore, according to the present invention, the sliding surface of the shaft-side sliding member is formed into a spherical convex shape, and the sliding surface of the bearing body is also formed into a spherical concave shape to be joined to the sliding surface. The moving surface has a structure capable of rotating around the axis while being joined to the sliding surface of the concave bearing main body. Also, an oil groove is provided on the sliding surface of this bearing body to divide the sliding surface and
A configuration is also provided in which each sliding surface is inclined with respect to the rotation direction and is in contact with the surface of the shaft-side sliding body.

That is, the present invention comprises (1) a rotating shaft that rotates about an axis, a shaft-side sliding member attached to the lower surface of the rotating shaft, and a bearing body that slides with the coaxial-side sliding member. A sliding bearing that receives an axial load on the shaft side, the sliding surface of the shaft-side sliding body forms a spherical convex shape, and the sliding surface of the bearing body joins with the sliding surface of the coaxial-side sliding body. (EN) Provided is a self-aligning thrust slide bearing which has a shape and is capable of shaft rotation in an inclined state.

(2) In the invention of (1) above, the sliding surface of the bearing body is divided by a plurality of oil grooves, and each sliding surface is inclined with respect to the rotation direction. There is also provided a self-aligning thrust slide bearing characterized by forming a spherical concave shape so as to come into contact with the side sliding body.

[0010]

According to the invention of the first aspect, the present invention provides, in the invention of (1), even when the rotary shaft is rotated and greatly slanted while receiving a thrust load, a sliding surface having a spherical convex shape of the shaft-side sliding member is provided. The spherical concave sliding surfaces of the bearing body maintain a joint relationship with each other, and the shaft-side sliding body can uniformly receive the thrust load and rotate about the axis.

Further, in the invention of (2), the lubricating oil can be positively supplied from the plurality of oil grooves to the sliding surface between the shaft-side sliding body and the bearing body by static pressure. The sliding surfaces of the bearing body, which are divided by multiple oil grooves, are in contact with each other with an inclination in the direction of rotation, so the lubricating oil is supplied from this inclined portion by dynamic pressure, and the wedge effect of the lubricating oil causes the sliding of the shaft The moving body floats slightly and forms an oil film. Therefore, in addition to the function and effect of the invention (1), a further lubricating effect can be obtained.

[0012]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a sectional view of a self-aligning thrust slide bearing according to a first embodiment of the present invention, and FIG. 2 is A in FIG.
3 is a sectional development view in the circumferential direction of the self-aligning thrust slide bearing in FIG.

In these figures, reference numeral 1 is a rotary shaft, and 2 is a shaft-side sliding member attached to the lower portion of the rotary shaft 1, which has a spherical convex sliding surface. The bearing body 3 has a spherical concave shape that is joined to the shaft side sliding body 2 that rotates and slides. Reference numeral 4 is a static pressure pocket provided in the bearing body 3, and reference numeral 6 is a hydraulic pipe joined to the static pressure pocket 4 via a throttle 5. As shown in FIG. 2, a plurality of static pressure pockets 4 are evenly arranged on the circumference. A hydraulic pump 7 is driven by an electric motor 8 and supplies lubricating oil to the static pressure pocket 4 via a check valve 10 and a hydraulic pipe 6 and a throttle 5. An air motor 9 is also connected to the hydraulic pipe 6 via a check valve 10.

In the first embodiment having such a structure, the bearing body 3 is provided with the static pressure pockets 4 and the throttles 5, and the hydraulic pump 7 supplies the lubricating oil to the plurality of static pressure pockets 4 through the hydraulic pipes 6. As shown in FIG. 3, the static load of the lubricating oil discharged from each static pressure pocket 4 resists the thrust load, and the shaft-side sliding body 2 slightly floats above the bearing main body 3, while the oil film 20 is formed between them. It is formed.

The hydraulic pump 7 is normally driven by an electric motor 8, but when the power is cut off, it is driven by an air motor 9 using compressed air as a backup to supply lubricating oil.

Next, FIG. 4 is a sectional view of a self-aligning thrust slide bearing according to a second embodiment of the present invention, FIG. 5 is a view taken along the line BB in FIG. 4, and FIG. It is a sectional development view of a thrust slide bearing in the peripheral direction.

In these figures, 1 is a rotary shaft, 2 is a shaft-side sliding member 2 attached to the lower part of the rotary shaft 1, and has a spherical convex sliding surface. Reference numeral 3 is a bearing main body and a shaft side sliding body 2
Although it has a spherical concave shape that slides with, a plurality of oil grooves 21 are provided as shown in FIG. 5, and the sliding surface is divided into a plurality of parts by the oil grooves. The sliding surface of the bearing body 3 has a spherical concave shape, but as shown in FIGS. 5 and 6, the land 2 has a slight inclination that narrows along the rotational direction and widens in the opposite direction.
Have two.

In the second embodiment having such a structure, the bearing body 3 is provided with a plurality of oil grooves 21 radially.
A plurality of lands 22 separated by the oil groove 21 are provided with a slight inclination along the rotation direction R of the shaft-side sliding body 2. Therefore, as shown in FIG. 6, the inclination of the land 22 causes the dynamic pressure of the rotation R of the shaft-side slide member 2 to cause the wedge effect of the lubricating oil film 20 to slightly float the shaft-side slide member 2 to form an oil film. To be done.

Next, FIG. 7 is a sectional view of a self-aligning thrust slide bearing according to a third embodiment of the present invention, FIG. 8 is a view taken along the line CC in FIG. 7, and FIG. It is a sectional development view of a thrust slide bearing in the peripheral direction. The third embodiment shown in these figures has a configuration having the functions of the first and second embodiments.

In these figures, 1 is a rotary shaft, 2 is a shaft-side sliding body, 3 is a bearing body, 21 is a plurality of oil grooves provided in the bearing body 3, and 22 is a land thereof. This is the same as the second embodiment shown in FIGS. or,
Reference numeral 4 is a static pressure pocket, 5 is a throttle, 6 is hydraulic piping, 7 is a hydraulic pump, 8 is its electric motor, 9 is a backup air motor, and 10 is a check valve. These are the same configurations as those of the first embodiment. Therefore, detailed description is omitted. In short, the third
The embodiment is an example in which the lubricating oil supply system shown in the first embodiment is added to the configuration of the second embodiment.

In the third embodiment having such a structure, a plurality of oil grooves 21 are radially provided in the bearing main body 3, and a plurality of lands 22 divided by the oil grooves 21 are shown in FIG.
As shown in FIG. 7, a slight inclination is provided along the rotation direction R of the shaft-side slide body 2. A hydraulic pump 7 is applied to a static pressure pocket 4 at the center of each land 22 through a throttle 5 to provide hydraulic piping 6
Lubricating oil is supplied through.

As shown in FIG. 9, the static pressure of the lubricating oil discharged from each static pressure pocket 4 causes the shaft-side sliding body 2 to slightly float above the bearing body 3 against the thrust load, and the oil film 2
0 is formed. At the same time, due to the inclination of the land 22, the shaft-side sliding body 2 is further floated by the wedge effect of the lubricating oil due to the dynamic pressure of the rotation of the shaft-side sliding body 2, and the oil film thickness is increased.

The hydraulic pump 7 is normally driven by an electric motor 8, but when the power is cut off, it is driven by an air motor 9 using compressed air as a backup.

In the third embodiment, normally, the lubricating oil is supplied by the hydraulic pump 7, the shaft-side sliding body 2 floats by the static pressure, and the wedge effect, that is, the motion, which occurs with the rotation of the shaft-side sliding body 2, is generated. It rises further by pressure.

However, when the lubricating oil is not supplied from the hydraulic pump 7 at the time of emergency such as power cutoff or compressed air cutoff, as in the second embodiment, the wedge effect, that is, the dynamic pressure alone, causes the axial slide body 2 to move. Levitation is maintained.

As described above, in the first embodiment described above, the bearing surfaces of the shaft-side sliding body 2 having the spherical convex sliding surface and the bearing main body 3 having the spherical concave sliding surface joined thereto are used as the bearing surfaces. A plurality of static pressure pockets 4 are provided so that the hydraulic pump 7 supplies the lubricating oil by static pressure. In the second embodiment, the shaft side sliding body 2 and the bearing body 3 sliding on the shaft side sliding body 2 are slightly inclined. Is provided to form a lubricating oil film by a wedge effect due to dynamic pressure.
In the third embodiment, the inclined land 22 having the structure of the second embodiment is provided to provide lubrication by dynamic pressure, and the static pressure pocket in the first embodiment is provided to supply the lubricating oil with the hydraulic pump 7. It is configured to supply by static pressure, and as in the first to third embodiments, an oil film 20 is formed between the shaft side sliding body 2 and the bearing body 3 to receive a thrust load, and as a slide bearing. It works.

In the first to third embodiments as described above, when the axis of the rotary shaft 1 is inclined by θ as shown in FIG. 10 (usually 1 to 2 °), the shaft side receives the thrust load. An oil film 20 is formed between the sliding body 2 and the bearing body 3, and the sliding body 2 can rotate around the axis along the spherical surface. In addition,
The allowable inclination angle of the shaft center is usually about 1 to 2 °, but by changing the dimensional specifications such as the linear system of the shaft-side sliding body 2 and the bearing body 3 and the spherical radius, a larger inclination angle can be obtained. Can also be acceptable.

Further, since the structures of the first to third embodiments are simple, the upper and lower leveling plates 16 and 1 are different from the conventional type.
The manufacturing cost can be reduced because a complicated structure combining 7 and the like is not required. Therefore, it is possible to inexpensively provide a self-aligning thrust slide bearing having a large allowable tilt angle of the axial center.

[0029]

As described above in detail, in the present invention, the sliding surface of the shaft-side sliding member has a spherical convex shape, and the bearing body sliding on this has a spherical concave shape. Therefore, even when the rotating shaft is largely inclined with respect to the shaft center, it is possible to smoothly maintain the rotation while receiving the thrust load.

Further, since the sliding surface of the bearing body is divided by the oil groove, and the sliding surface is inclined and contacted with respect to the rotating direction, the lubricating effect is increased, and the thrust load is increased even in the case of a large inclination. The rotation can be smoothly maintained while receiving the force.

Further, since the bearing structure does not have a complicated mechanism such as a combination of upper and lower sliding plates as compared with the conventional structure, the manufacturing cost can be reduced, and the self-aligning with a large allowable tilt angle of the axial center. A thrust slide bearing can be provided at low cost.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a self-aligning thrust slide bearing according to a first embodiment of the present invention.

FIG. 2 is a view on arrow AA in FIG.

FIG. 3 is a circumferential sectional development view of the self-aligning thrust sliding bearing in FIG.

FIG. 4 is a cross-sectional view of a self-aligning thrust slide bearing according to a second embodiment of the present invention.

5 is a BB arrow view in FIG. 4. FIG.

FIG. 6 is a circumferential sectional development view of the self-aligning thrust sliding bearing in FIG.

FIG. 7 is a sectional view of a self-aligning thrust sliding bearing according to a third embodiment of the present invention.

8 is a view on arrow CC in FIG. 7. FIG.

9 is a circumferential sectional development view of the self-aligning thrust sliding bearing in FIG. 7.

FIG. 10 is a cross-sectional view of the self-aligning thrust sliding bearing of the present invention in a state where the rotary shaft is inclined.

FIG. 11 is a sectional view of a conventional self-aligning thrust plain bearing.

FIG. 12 is a view on arrow D-D in FIG. 11.

FIG. 13 is a circumferential sectional development view of the conventional self-aligning thrust slide bearing in FIG. 11.

[Explanation of symbols]

 1 rotary shaft 2 shaft side sliding body 3 bearing body 4 static pressure pocket 5 throttle 6 hydraulic piping 7 hydraulic pump 8 electric motor 9 air motor 20 oil film 21 oil groove 22 land

Claims (2)

[Claims] 1. An axial load is constituted by a rotary shaft that rotates about an axis, a shaft-side sliding body that is attached to the lower part of the rotary shaft, and a bearing body that slides with the coaxial-side sliding body. In a slide bearing, the sliding surface of the shaft-side sliding body has a spherical convex shape, and the sliding surface of the bearing body has a spherical concave shape that joins with the sliding surface of the coaxial-side sliding body. A self-aligning thrust slide bearing that can rotate the shaft in a tilted state. 2. The sliding surface of the bearing body is divided by a plurality of oil grooves, and each sliding surface is formed in a spherical concave shape so as to be inclined with respect to the rotation direction and contact the shaft side sliding body. The self-aligning thrust slide bearing according to claim 1, wherein