JPH09210053A - Thrust bearing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thrust bearing with a low-priced stationary board which can join a bearing sliding surface forming board (polytetrafluoroethylene molding board or the like) with a base metal easily and which has high joining strength, capable of maintaining joining strength for a long time. SOLUTION: For stationary board for thrust bearing, a trapezoid protruding part 12a whose cross section in the thickness direction is of reversed trapezoid shape, is formed by processing. At the position facing the trapezoid protruding part 12a, a trapezoid recessed part 13a whose cross section is of trapezoid shape is formed. A sheet material 12A is joined integrally with a metal mold 13A by fitting both of them, and an anchoring effect is obtained by fitting the trapezoid protruding part 12a onto the trapezoid recessed part 13a.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to thrust bearings, and is particularly useful when applied to thrust bearings of water turbine generators and the like.

[0002]

2. Description of the Related Art In order to cope with higher peripheral speeds and larger capacities of vertical rotating electric machines (vertical turbine generators, etc.), the wear resistance of the bearing sliding surface has been improved and the coefficient of friction has been reduced to reduce the As a material for forming the bearing sliding surface of the stationary plate (thrust pad) in order to increase the surface pressure and significantly reduce bearing loss,
Thrust bearings have been proposed that have a stationary plate that uses polytetrafluoroethylene (trade name: Teflon) instead of a bearing material alloy that is mainly composed of metal such as tin.

The specific construction of this conventional stationary plate is shown in FIGS.
It will be described with reference to FIG. 5 is a perspective view of the conventional stationary plate having the first structure, FIG. 6 is a sectional view thereof, and FIG. 7 is a sectional view of the conventional stationary plate having the second structure.

As shown in FIGS. 5 and 6, the stationary plate 01A of the first structure has a fan-shaped plane, is radially arranged around the rotation axis, and slidably supports the rotation part. (This also applies to the stationary plate 01B described later). Then, as shown in FIG. 6, the stationary plate 01A includes a sheet material 02 made of polytetrafluoroethylene that forms a bearing sliding surface,
An iron-based thrust pad base metal (hereinafter referred to as “base metal”) 03 is integrally joined to the lower side of the sheet material 02. This integral joining is performed by the sheet material 02 and the base metal 03.
For example, a soft adhesive is used to join the two.

The stationary plate 01B of the second construction shown in FIG.
A concave portion 03a having an inverted trapezoidal cross section is formed on the surface of the base metal 03, and a convex portion 02a formed by heating and pressurizing powdery polytetrafluoroethylene by the mold is provided on the surface of the sheet material 02. Then, both are integrally molded.

[0006]

However, in the stationary plate of the thrust bearing according to the above-mentioned prior art, a sheet material such as polytetrafluoroethylene is used as the sliding surface. Since the adhesiveness is not good in joining, there are the following problems in joining to a metal base metal.

In the stationary plate 01A shown in FIGS. 5 and 6, the sheet material 02 is joined to the base metal 03 with an adhesive, but there is a problem in the joining strength and the durability thereof. That is, the adhesive cannot avoid deterioration over time, and the durability of the joint deteriorates over time.

Further, the stationary plate 01B shown in FIG. 7 has good joining strength and durability, but the manufacturing process is complicated, so that a large amount of cost is required for manufacturing. That is, since powdery polytetrafluoroethylene is melted at a high temperature using a mold and fired to form the trapezoidal protrusions 03a, the trapezoidal protrusions 03a are joined to each other. Requires a lot of man-hours.

Further, since a die is used, it is necessary to prepare a die for each base metal having a different shape, which requires a great deal of cost. Further, the pressurization needs to be about 350 kgf / cm ² . Therefore, when the size of the base metal becomes large, a considerably large press molding machine is required, additional investment of equipment is required, and the cost required for manufacturing increases.

In view of the above-mentioned problems of the prior art, the present invention makes it possible to easily join a plate (polytetrafluoroethylene molded plate or the like) forming a bearing slip surface to a base metal and has a high joining strength. An object of the present invention is to provide a thrust bearing provided with an inexpensive stationary plate that can maintain the bonding strength for a long period of time.

[0011]

Means for Solving the Problems A first method for solving the above problems is described below.
Of the present invention is a thrust bearing including a stationary plate that slidably supports a rotating portion, wherein the stationary plate joins a sheet material forming a bearing sliding surface that is in sliding contact with the rotating portion and a base metal. At this time, the surface of the sheet material is processed to form a concave portion or a convex portion in the cross-sectional shape, and the opposite base metal surface is formed with a convex portion or a concave portion having the cross-sectional shape integrally fitted with the concave portion or the convex portion. It is characterized in that both are fitted together and integrally joined.

Therefore, according to the present invention having the above structure, a trapezoidal concave portion or a convex portion is formed by simply processing the sheet material, and the concave portion or the convex portion of the sheet material is formed on the surface of the opposite base metal. Since the convex part or concave part that fits together is formed and the parts are joined together by fitting, it is not necessary to form the convex part with a mold as in the conventional case, and the manufacturing cost can be reduced. Becomes

A second aspect of the present invention is a thrust bearing including a stationary plate slidably supporting a rotating portion, wherein the stationary plate forms a bearing sliding surface in sliding contact with the rotating portion and has a thickness. A sheet material having a recess having a trapezoidal cross section in a direction, a base metal having a recess having a trapezoidal cross section at a position facing the recess of the sheet material, and a space formed when these are opposed to each other. In addition, the low melting point metal is heated and filled, and the sheet material and the base metal are integrally joined by the low melting metal.

Therefore, according to the present invention having the above-mentioned structure, the sheet material (for example, the sheet material made of polytetrafluoroethylene) forming the bearing sliding surface is easily integrated with the base metal by the metal having a lower melting temperature than that. Since they can be joined together, and because they are joined by metal, the joining strength between the sheet material and the base metal can be maintained for a long time.

Further, in the above invention, when the sheet material and the mold are integrated, they are joined by using an adhesive.

Further, the above invention is characterized in that the sheet material is a fluororesin-based molding plate such as polytetrafluoroethylene.

[0017]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a sectional view showing a structure of a stationary plate of a thrust bearing according to a first embodiment of the present invention, FIG. 2 is a sectional view of a stationary plate of a thrust bearing according to a second embodiment, and FIG. FIG. 4 is a sectional view of a base metal of a thrust bearing according to the third embodiment and FIG. 4 is a sectional view of a stationary plate of the thrust bearing according to the fourth embodiment.

(First Embodiment) As shown in FIG.
The stationary plate 11A according to the first embodiment has a fan-shaped plane as in the conventional case, is radially arranged around the rotation axis, and slidably supports the rotating portion (this point will be described later). The same applies to stationary plates 11B and 11D.

As shown in FIG. 1, the stationary plate 11A is formed by fitting a sheet material 12A which forms a bearing sliding surface that is in sliding contact with a rotating portion and an iron base metal 13A to each other by processing them. It is integrally joined by means. Here, the sheet material 12A is a sheet-shaped plate formed by molding polytetrafluoroethylene, which is a kind of fluororesin.

The sheet material 12A is formed with a trapezoidal convex portion 12a having an inverted trapezoidal cross section in the thickness direction by processing, and one base metal 13A is formed at a position facing the trapezoidal convex portion 12a. A trapezoidal recess 13a having a trapezoidal cross section is formed, and the sheet material 12A and the die 13A are integrally joined by fitting them together. Therefore, the anchor effect is provided by fitting the trapezoidal convex portion 12a and the trapezoidal concave portion 13a.

The stationary plate 11A is manufactured as follows.

A sheet material 12A shown in FIG. 1 is formed by processing a plurality of trapezoidal convex portions 12a having an inverted trapezoidal cross section on a sheet material made of polytetrafluoroethylene. Next, a trapezoidal recess 13a having a trapezoidal cross section is formed on the surface of the base metal 13A to fit the trapezoidal projection 12a. The trapezoidal convex portion 12a and the trapezoidal concave portion 13a may have an inverted truncated cone shape, a rectangular shape, or may be formed along the axial direction.

The sheet material 12A and the base metal 13A are bonded and integrated with each other by using an adhesive on the joint surface when the convex portion 12a and the concave portion 13a are fitted.

(Second Embodiment) A stationary plate 1 shown in FIG.
1B is a stationary plate 11A of the first embodiment shown in FIG.
And the formation of irregularities is reversed. In FIG. 2, a sheet material 12B is formed with a plurality of trapezoidal recesses 12b having an inverted trapezoidal cross section in the thickness direction by processing, and one base metal 13B is formed at a position facing the trapezoidal recess 12b. A trapezoidal convex portion 13b having an inverted trapezoidal cross section is formed, and the sheet material 12B and the mold 13B are integrally joined by fitting them together. At this time, the trapezoidal concave portion 12b and the trapezoidal convex portion 13
It is the first to give an anchor effect by fitting with b.
This is the same as the embodiment.

(Third Embodiment) FIG. 3 shows another embodiment of the base metal 13B of the stationary plate 11B shown in FIG.

As shown in FIG. 3, on the surface of the base metal 13C,
The trapezoidal convex portion 13c is integrally formed by a spot welding method or the like.

Therefore, the sheet material 12B shown in FIG. 2 and the base metal 13C shown in FIG. 3 are the concave portions 12b of the sheet material 12B.
The trapezoidal member 13c having an inverted trapezoidal cross-section formed by the above spot welding is fitted, and at the time of fitting, an adhesive agent is used for the joining surface to bond and integrate them.

(Fourth Embodiment) The stationary plate 1 shown in FIG.
As shown in FIG. 4, 1D is a sheet metal 12D that forms a bearing sliding surface that is in sliding contact with the rotating portion, and is attached to an iron base metal 13D.
It is integrally joined by using the low melting point metal 14. Here, the sheet material 12D is a sheet-shaped plate formed by molding polytetrafluoroethylene, which is a kind of fluororesin.

This sheet material 12D is formed with a plurality of trapezoidal recesses 12b having an inverted trapezoidal cross section in the thickness direction, and one base metal 13A also has a cross section at a position facing the trapezoidal recess 12b. A trapezoidal recess 13a having a trapezoidal shape is formed. Then, the low-melting-point metal 14 is heated and filled in the space formed when the two are opposed to each other, and is cooled and solidified. Therefore, the anchor effect is provided by the low melting point metal 14 that is filled and solidified in the space.

The stationary plate 11D is manufactured as follows.

A sheet material 12D shown in FIG. 4 is formed by processing a plurality of trapezoidal recesses 12b having an inverted trapezoidal cross section in a sheet material made of polytetrafluoroethylene. Next, a trapezoidal recess 13a is formed on the surface of the base metal at a position corresponding to the trapezoidal recess 12b, and the sheet material 1 shown in FIG.
3D.

The sheet material 12D and the base metal 13D are joined together to form a space portion by the recess 12b and the recess 13a. An adhesive is used for this joining.

Next, the space portion is heated and filled with a low melting point metal such as white metal, cooled to solidify the low melting point metal, and the both are integrally bonded through the low melting point metal 14. It will be.

From the above, the stationary plate 11 having the above structure
According to A, 11B, and 11D, the following effects can be obtained.

The sheet material and the base metal can be integrally joined at a comparatively low cost by using a special mold as in the prior art without requiring a separate large-scale facility. The manufacturing cost can be reduced.

As shown in FIGS. 1 to 3, the sheet material and the base metal are joined to each other by processing the sheet material or the base metal instead of the conventional soft adhesive to form the uneven portion. Only by forming the thrust bearing, it is possible to construct an extremely reliable thrust bearing without deterioration due to aging or thermal deterioration.

Further, a stationary plate 11D as shown in FIG.
As described above, the space formed when the sheet material 12D having the recessed portion 12b and the base metal 13D having the recessed portion 13a are joined is heated and filled with a low-melting point metal so as to be solidified. Therefore, the process can be simplified and the cost can be reduced.

[0039]

As described above in detail with the embodiments of the invention, according to the present invention, a unique mold as in the prior art is formed to melt the powdery polytetrafluoroethylene at a high temperature. Then, it is possible to manufacture the thrust bearing at low cost without the trouble of firing and firing and joining with the base metal.

[Brief description of drawings]

FIG. 1 is a sectional view showing a configuration of a stationary plate of a thrust bearing according to a first embodiment of the present invention.

FIG. 2 is a sectional view of a stationary plate of a thrust bearing according to a second embodiment.

FIG. 3 is a sectional view of a base metal of a thrust bearing according to a third embodiment.

FIG. 4 is a sectional view of a stationary plate of a thrust bearing according to a fourth embodiment.

FIG. 5 is a perspective view of a conventional stationary plate having a first configuration.

FIG. 6 is a sectional view of FIG. 5;

FIG. 7 is a perspective view of a conventional stationary plate having a second configuration.

[Explanation of symbols]

 11A, 11B, 11D stationary plate 12A, 12B, 12D sheet material 12a trapezoidal convex portion 12b trapezoidal concave portion 13a trapezoidal concave portion 13b trapezoidal convex portion 13c trapezoidal member 13A, 13B, 13C, 13D base metal 14 low melting point metal

Claims (4)

[Claims] 1. A thrust bearing including a stationary plate that slidably supports a rotating portion, wherein the stationary plate joins a base material and a sheet material that forms a bearing sliding surface in sliding contact with the rotating portion. In doing so, the surface of the sheet material is processed to form a concave portion or a convex portion with a cross-sectional shape, and a convex portion or a concave portion with which the cross-sectional shape is integrally fitted with the concave portion or the convex portion is formed on the surface of the opposite base metal. A thrust bearing characterized in that it is formed, and both are fitted together and integrally joined. 2. A thrust bearing comprising a stationary plate for slidably supporting a rotating part, wherein the stationary plate forms a bearing sliding surface in sliding contact with the rotating part and has a sectional shape in the thickness direction. A sheet material in which an inverted trapezoidal recess is formed, a base metal in which a recess having a trapezoidal sectional shape is formed at a position facing the recess of the sheet material, and a low melting point metal in a space formed when these are opposed to each other A thrust bearing characterized in that the sheet material and the base metal are integrally joined by the low-melting metal. 3. The thrust bearing according to claim 1, wherein the sheet material and the mold are joined together by using an adhesive when they are integrated. 4. The thrust bearing according to claim 1, wherein the sheet material is a polytetrafluoroethylene fluororesin molded plate.