JP7179726B2 - Seismic isolation slide bearing - Google Patents

Description

The present disclosure relates to a seismic isolation sliding bearing device.

Japanese Patent Application Laid-Open No. 2004-144135 (Patent Document 1) discloses that, in a sliding member used in a sliding and seismic isolation device, the sliding surface of a substrate having a porous structure is partially impregnated with a lubricant to lubricate the entire sliding surface. A technique is disclosed in which the coefficient of friction of the sliding surface is controlled by adjusting the area ratio occupied by the agent-impregnated portion.
Further, Japanese Patent Application Laid-Open No. 2002-98189 (Patent Document 2) discloses that a concave portion is formed in the lower surface of a sliding member that slides on a smooth plate, and at least one of the smooth plate and the sliding member is made of porous silica and lubricant. A technique of molding with a resin composition containing at least an agent is disclosed.

However, in the conventional example described in Patent Document 1, the sliding surface partially impregnated with the lubricant is on the lower structure side, and the capacity of the lubricant at the lubricant-impregnated portion is fixed.
Further, in the conventional example described in Patent Document 2, a concave portion is formed in the lower surface of the sliding member itself. It is necessary to

In consideration of the above facts, the present disclosure maintains the low friction properties of the first sliding member for a long period of time, while increasing the degree of freedom in the depth and shape of the dimples that are formed in the first sliding member and that are capable of storing lubricant. Aim to raise.

A seismic isolation sliding bearing device according to the present disclosure is interposed between a lower structure and an upper structure disposed above the lower structure, and fixed to one of the upper structure and the lower structure. a sliding bearing body; a first sliding member provided on said sliding bearing body and having a sliding surface for the other of said upper structure and said lower structure; and interposed between said sliding bearing body and said first sliding member. a holding member provided with a bottomed recess that holds the first sliding member and allows the first sliding member to deform in a direction away from the other of the upper structure and the lower structure; have

According to the seismic isolation sliding bearing device according to the present disclosure, while maintaining the low friction properties of the first sliding member for a long period of time, the depth and shape of the dimples formed in the first sliding member and capable of storing the lubricant are free. degree can be increased.

It is a sectional view showing a seismic isolation sliding bearing device concerning this embodiment. FIG. 2 is an enlarged cross-sectional view of a main part showing the seismic isolation sliding bearing device according to the present embodiment; (A) is a front view showing the shape of a bottomed recess in a holding member. 3B is an enlarged cross-sectional view taken along line 3B-3B in FIG. 3A, showing the shapes of bottomed recesses having equal depths; FIG. 3(C) is an enlarged cross-sectional view corresponding to the arrow 3B-3B in FIG. 3(A), showing the shapes of bottomed recesses having different depths. (A) is an enlarged cross-sectional view showing an example in which the width of the bottomed concave portion increases toward the surface of the holding member on the side of the first sliding member. (B) is an enlarged cross-sectional view showing an example in which the corner portion of the bottomed concave portion on the side of the first sliding member in (A) is a rounded surface. 4 is a diagram showing the relationship between the number of repetitions of friction and the amount of change in coefficient of friction according to Test Example 1. FIG. (A) is a front view showing shapes of bottomed recesses and grooves in a holding member according to Modification 1. FIG. 6B is an enlarged cross-sectional view taken along line 6B-6B in FIG. 6A, showing an example in which the bottomed recess and the groove have the same depth; FIG. (C) is an enlarged cross-sectional view corresponding to the arrow 6B-6B in FIG. 6(A), showing an example in which the depth of the groove is shallower than the depth of the bottomed recess. (A) is a front view showing the shape of a bottomed recess in a holding member according to Modification 2. FIG. (B) is a cross-sectional view taken along line 7B-7B in FIG. 7(A). FIG. 11 is a front view showing the shape of a recessed portion with a bottom in a holding member according to Modified Example 3; 1 is a cross-sectional view showing an embodiment of a seismic isolation sliding bearing device; FIG. 1 is a cross-sectional view showing an embodiment of a seismic isolation sliding bearing device; FIG. 1 is a cross-sectional view showing an embodiment of a seismic isolation sliding bearing device; FIG. FIG. 14 is an enlarged view of a portion A in FIGS. 11 and 13; 1 is a cross-sectional view showing an embodiment of a seismic isolation sliding bearing device; FIG. 14 is an enlarged view of a B portion in FIG. 13; FIG. FIG. 11 is a cross-sectional view showing a modification of the recess in the first sliding member; FIG. 11 is a cross-sectional view showing a modification of the recess in the first sliding member; FIG. 11 is a cross-sectional view showing a modification of the recess in the first sliding member; FIG. 11 is a cross-sectional view showing a modification of the recess in the first sliding member; FIG. 11 is a cross-sectional view showing a modification of the recess in the first sliding member;

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments for carrying out the present invention will be described based on the drawings. FIG. 1 is a cross-sectional view showing a seismic isolation sliding bearing device according to this embodiment. In FIG. 1 , a seismic isolation sliding bearing device 10 according to this embodiment has a sliding bearing main body 12 , a first sliding member 14 and a holding member 16 .

The sliding bearing body 12 is interposed between the lower structure 18 and an upper structure 20 arranged above the lower structure 18, and is attached to one of the upper structure 20 and the lower structure 18, for example, the upper structure 20. Fixed. The upper structure 20 is a supported body such as a building, a tank, or a water tank. The lower structure 18 is, for example, a foundation portion made of concrete or the like, and is installed on the ground (not shown).

The slide bearing main body 12 is constructed by fixing an upper mounting plate 26 to the upper end of a laminate 22 and a connecting plate 28 to the lower end. The laminate 22 is formed in a columnar shape by alternately laminating a plurality of disc-shaped metal plates 30 and a plurality of disc-shaped rubbers 34 in the thickness direction. are placed in The metal plate 30 is, for example, a steel plate. The metal plate 30 and the rubber 34 are firmly integrated by vulcanization adhesion. As a result, it has a predetermined rigidity against a load in the vertical direction (direction of arrow V), and exhibits a spring function and secures a predetermined amount of deformation against a load in the horizontal direction (direction of arrow H). is possible.

The upper mounting plate 26 and the connecting plate 28 are each made of a thick disc-shaped steel plate. The outer diameter of the upper mounting plate 26 is larger than the outer diameter of the slide bearing body 12 and is bolted to the upper structure 20 (not shown), for example. The outer diameter of the connecting plate 28 is set equal to the outer diameter of the metal plate 30 , and a covering rubber 36 is cylindrically arranged around the outer circumferences of the laminate 22 and the connecting plate 28 . Since the outer edge of the metal plate 30 is covered with the covering rubber 36, the metal plate 30 and the connecting plate 28 are not exposed to the outside and are prevented from deteriorating.

In FIG. 1, the sliding bearing main body 12 receives a load from the upper structure 20, the rubber 34 is slightly compressed and deformed, and the length in the vertical direction becomes shorter than in the unloaded state. When the upper structure 20 moves horizontally relative to the lower structure 18 in this state, the vibration energy of this relative movement is partially absorbed by the shear deformation of the slide bearing body 12 .

The first sliding member 14 is provided on the sliding bearing body 12 and is a low-friction member having a sliding surface 14A against the other of the upper structure 20 and the lower structure 18 . The material of the first sliding member 14 is, for example, a low-friction resin containing tetrafluoroethylene resin as a main component. The first sliding member 14 is provided, for example, on the lower end side of the sliding bearing main body 12 via the holding member 16 .

The material of the first sliding member 14 is, for example, one of the following (1) to (5). These are formulations that can improve both the reduction of the friction coefficient and the mechanical strength of the first sliding member 14 .

(1) Tetrafluoroethylene resin composition containing aromatic polyester or polyimide.
(2) A tetrafluoroethylene resin composition containing 5 to 30% by weight of an aromatic polyester.
(3) A tetrafluoroethylene resin composition containing 5 to 30% by weight of polyimide.
(4) Any one of 1) to 3) above, further containing one or more of carbon fiber, graphite, glass fiber, molybdenum disulfide, potassium titanate, and bronze.
(5) Any one of 1) to 3) above, further containing one or more of carbon fiber, graphite, glass fiber, molybdenum disulfide, potassium titanate, and bronze in an amount exceeding 0 and 5 to 20 wt%. .
In (4) and (5) above, graphite and molybdenum disulfide are more preferable than other materials from the viewpoint of friction characteristics.

The coefficient of friction of the first sliding member 14 at a surface pressure of 20 MPa is, for example, 0.01 or less, more preferably 0.008 or less. The compressive strain amount of the first sliding member 14 when the surface pressure is 80 MPa is, for example, 40% or less.

The first sliding member 14 is, for example, disc-shaped and is fitted into the recess 16A of the holding member 16 . Here, the outer diameter of the first sliding member 14 is smaller than the outer diameter of the holding member 16, but the edge for fitting the first sliding member 14 to the holding member 16 (the edge of the recessed portion 16A, which will be described later) is eliminated so that FIG. 9, the outer diameter of the first sliding member 14 may be the same as the outer diameter of the retaining member 16, or may be larger than the outer diameter, as shown in FIG. Further, the recess 16A is formed shallower than the thickness of the first sliding member 14. As shown in FIG. Thereby, the first sliding member 14 protrudes below the holding member 16 . The first sliding member 14 is fixed to the holding member 16, for example by gluing. Further, the outer diameter of the first sliding member 14 is not limited to being smaller than the outer diameter of the holding member 16, and the outer diameter of the first sliding member 14 may be substantially equal to the outer diameter of the holding member 16. It may be larger than the outer diameter of member 16 .

The holding member 16 is interposed between the sliding bearing body 12 and the first sliding member 14 and holds the first sliding member 14 . The holding member 16 is made of metal such as stainless steel, and is shaped like a disk. A circular recess 16A into which the first sliding member 14 is fitted is formed at the lower end of the holding member 16 (the end on the side of the first sliding member 14). The holding member 16 is fastened to the connecting plate 28 with bolts or the like (not shown). Further, the holding member 16 is not limited to a disc shape, and may be, for example, a square shape.

The holding member 16 is provided with a bottomed recess 40 that allows the first sliding member 14 to deform in a direction away from the other of the upper structure 20 and the lower structure 18 , for example, the lower structure 18 . FIG. 3A is a front view showing the shape of the bottomed recess 40 in the holding member 16. FIG. FIG. 3(B) is an enlarged cross-sectional view taken along line 3B-3B in FIG. 3(A), showing the shape of bottomed recesses 40 having equal depths. FIG. 3(C) is an enlarged cross-sectional view corresponding to the arrow 3B-3B in FIG. 3(A), showing the shapes of bottomed recesses 40 having different depths.

The bottomed concave portion 40 is a deformation-permitting portion that does not penetrate the holding member 16 , and is, for example, two annular grooves (an inner concave portion 40A and an outer concave portion 40B) formed concentrically with the holding member 16 . For example, a plurality of bottomed recesses 40 are formed in this manner.

The bottomed recesses 40 are more densely arranged on the outside of the holding member 16 than on the inside. Here, when the holding member 16 is disk-shaped, the inner side of the holding member 16 is a region of half the radius of the holding member 16 from the center of the holding member 16 to the outside. When the holding member 16 has a rectangular shape, the inside of the holding member 16 is an inner area of 1/4 of one side of the holding member 16 outward from the center of the holding member 16 .

When the holding member 16 is disc-shaped, the outer side of the holding member 16 is an area of half the radius of the holding member 16 from the outer edge of the recess 16A of the holding member 16 to the inside. When the holding member 16 has a rectangular shape, the outside of the holding member 16 is a quarter area of one side of the holding member 16 from the outer edge of the portion corresponding to the recess 16A of the holding member 16 to the inside.
“Dense” indicates the total area (width×depth×length) of the bottomed concave portion 40 . In other words, the volume of the bottomed recess 40 is set larger on the outside than on the inside of the holding member 16 .

The bottomed recesses 40 are not limited to annular grooves, and may be recesses of various shapes such as scattered recesses and recesses extending linearly or curvedly (not shown).

FIG. 2 is an enlarged cross-sectional view of a main part showing the seismic isolation sliding bearing device 10 according to this embodiment. In FIGS. 2 and 3(B), the depths d of the two bottomed recesses 40 may be the same, or may be at least partially different from each other as shown in FIG. 3(C). In FIG. 3C, the depth d2 of the outermost recess 40B is deeper than the depth d1 of the inner recess 40A. The depth d of the bottomed recess 40 is smaller than the width w of the bottomed recess 40 and smaller than the thickness t of the first sliding member 14 . 2 and 3A, the width w of the bottomed recess 40 is constant.

On the other hand, in the example shown in FIG. 4, the width w of the bottomed concave portion 40 widens as it approaches the surface of the holding member 16 on the side of the first sliding member 14 . Here, the surface of the holding member 16 on the side of the first sliding member 14 is the bottom surface of the recess 16A. Specifically, in the example shown in FIG. 4A , the vertical wall portion 41 of the bottomed recess 40 is inclined with respect to the depth direction of the bottomed recess 40 . Further, in the example shown in FIG. 4B, the corner 43 of the similarly inclined vertical wall 41 on the side of the first sliding member 14 is a rounded surface.

The other of the upper structure 20 and the lower structure 18 is provided with a second sliding member 24 having a sliding surface 24A against the first sliding member 14 . The material of the second sliding member 24 is, for example, the same as that of the first sliding member 14, but stainless steel or the like can also be used. As shown in FIG. 2, a lubricant 42 is disposed between the first sliding member 14 and the second sliding member 24. As shown in FIG. This lubricant 42 mainly accumulates in the dimples 44 formed at the positions of the bottomed recesses 40 and the second sliding member 24 .

(Action)
This embodiment is configured as described above, and the operation thereof will be described below. In FIG. 1, a seismic isolation sliding bearing device 10 according to the present embodiment is fixed to one of an upper structure 20 and a lower structure 18, for example, the upper structure 20, and the upper structure 20 and the lower structure 18 are fixed to each other. intervene in between. Then, a load acts on the lower structure 18 from the upper structure 20 via the slide bearing body 12, and the first sliding member 14 held by the holding member 16 receives a compressive load.

At this time, as shown in FIG. 2, the bottomed recess 40 of the holding member 16 is not in contact with the first sliding member 14, so that a portion of the compressed first sliding member 14 is not in contact with the bottomed recess. It transforms into 40. Since the outer edge of the first sliding member 14 is fitted into the recessed portion 16A of the holding member 16, the first sliding member 14 is prevented from spreading outside the recessed portion 16A. Therefore, the first sliding member 14 is deformed so that a part of the first sliding member 14 also enters the bottomed concave portion 40 of the peripheral portion of the holding member 16 .

As a result, the first sliding member 14 is deformed in a direction away from the other of the upper structure 20 and the lower structure 18 , which is the lower structure 18 in this embodiment, at the position of the bottomed recess 40 . As a result, a dimple 44 capable of retaining the lubricant 42 is formed between the first sliding member 14 and the second sliding member 24 (the other side of the lower structure 18). In the example shown in FIG. 1, since the bottomed recesses 40 are provided at a plurality of locations, the dimples 44 are also formed at a plurality of locations. Since the dimples 44 are naturally formed at positions corresponding to the bottomed recesses 40 of the holding member 16 when the first sliding member 14 receives a compressive load, a special mold is used to form the dimples 44. and post-processing of the first sliding member 14 is not required. Separately, it is also possible to process the first sliding member 14 in advance. For example, there is a case where a dimple shape is formed by cutting.

In this embodiment, since the deformation-allowing portion is the recessed portion 40 with a bottom, the deformation-allowing portion can be easily provided at the time of molding the first sliding member 14, and even when the deformation-allowing portion is provided in a post-processing, the processing is easy. Easy. Further, since the bottomed recess 40 is an annular groove, the bottomed recess 40 can be easily formed by cutting or the like.

In this embodiment, since the lubricant 42 accumulates between the dimples 44 formed on the first sliding member 14 and the second sliding member 24, Low friction properties can be maintained for a long period of time. When the upper structure 20 moves due to the action of an earthquake or the like, the first sliding member 14 slides against the second sliding member 24, thereby reducing the horizontal acceleration acting on the upper structure 20. can. At this time, the lubricant 42 in the dimples 44 is supplied between the sliding surface of the first sliding member 14 and the sliding surface of the second sliding member 24 . The horizontal acceleration acting on the upper structure 20 can be reduced by the sliding of the first sliding member 14 relative to the second sliding member 24 .

In addition, since the deformation-allowing portion provided in the holding member 16 is the recessed portion 40 with a bottom, compared with the case where the portion for allowing deformation of the first sliding member 14 is a through hole (not shown), There are less restrictions on the shape pattern of the dimples 44 . Specifically, it is possible to form the dimples 44 concentrically.

As shown in FIG. 2, since the depth d of the bottomed recess 40 is smaller than the thickness t of the first sliding member 14, the shape of the dimples 44 formed in the first sliding member 14 is smooth and the first sliding member 14 has a smooth shape. Distortion of the deformed portion of the member 14 is suppressed. Further, since the depth d of the bottomed recess 40 is smaller than the width w of the bottomed recess 40, compared to the case where the depth d of the bottomed recess 40 is larger than the width w of the bottomed recess 40, the first sliding member The shape of the dimples 44 formed on the first sliding member 14 is smoothed, and distortion of the deformed portion of the first sliding member 14 is suppressed.

In the example shown in FIGS. 4A and 4B, the width w of the bottomed recess 40 widens as it approaches the surface of the holding member 16 on the side of the first sliding member 14, so the first sliding member The shape of the dimples 44 formed on the first sliding member 14 becomes smooth, and distortion of the deformed portion of the first sliding member 14 is further suppressed.

Since the bottomed recesses 40 are arranged more densely on the outside of the holding member 16 than on the inside, the area on the outside of the holding member 16 through which the dimples 44 do not pass can be reduced. Therefore, the bias of the lubricant 42 within the holding member 16 can be alleviated.

When a plurality of bottomed recesses 40 are formed and the depths d of the plurality of bottomed recesses 40 are different from each other, the shape of the dimples 44 changes depending on the location. A large amount of the lubricant 42 can be held in places where a large amount of the lubricant 42 is required, such as the outer peripheral portion and the central portion of the .

Incidentally, the structure of the holding member 16 is not limited to the one described above, and may be the structures of Modifications 1 to 3 below. In FIG. 6A, a holding member 16 according to Modification 1 has a plurality of bottomed recesses 40 (an inner recess 40A and an outer recess 40B). At least part of the bottomed recess 40 has grooves 45 communicating with each other. For example, three grooves 45 are formed, extend in the radial direction of the holding member 16, and open to the inner recess 40A and the outer recess 40B. Each groove 45 is evenly arranged in the circumferential direction of the holding member 16 . In other words, each groove 45 is formed every 120°. With this configuration, the dimple 44 occupies a wider area, so a large amount of the lubricant 42 can be retained in locations where the lubricant 42 tends to be insufficient. The shape and number of the grooves 45 are not limited to this, and the bottomed recesses 40 in which the grooves 45 are not provided may exist.

In the example shown in FIG. 6B, the depth dg of the communicating groove 45 is equal to the depth d of the bottomed recess 40 (the inner recess 40A and the outer recess 40B). On the other hand, in the example shown in FIG. 6C, the depth dg of the communicating groove 45 is shallower than the depth d of the bottomed recess 40 (the inner recess 40A and the outer recess 40B). When the depth d of the bottomed recess 40 differs depending on the location, the depth dg of the groove 45 is shallower than the shallowest depth d. If the depth dg of the grooves 45 is not constant, the depth is taken as the average depth. By changing the depth dg of the groove, the amount of the lubricant 42 held by the holding member 16 can be finely adjusted.

7A and 7B, the holding member 16 according to Modification 2 has a bottomed concave portion 40 at the center. When the holding member 16 is disc-shaped, the central portion of the holding member 16 is a region including the center of the holding member 16 . When the holding member 16 has a square shape, the central portion of the holding member 16 is a region including the center of the holding member 16 and its periphery. Since the holding member 16 has the bottomed concave portion 40 in the central portion, a dimple 44 (see FIG. 2) capable of retaining the lubricant 42 is formed in the central portion of the first sliding member 14 . Therefore, the lubricant 42 can be held in the central portion of the first sliding member 14 where the lubricant 42 is most difficult to enter. In addition, various bottomed recesses may be further provided outside the center bottomed recess 40 (not shown).

In FIG. 8, the width of the bottomed concave portion 40 of the holding member 16 according to Modification 3 increases from the end portion of the holding member 16 toward the center. In this example, the width w1 of the inner recess 40A is wider than the width w2 of the outer recess 40B. When three or more annular grooves such as the inner recess 40A and the outer recess 40B are formed, the innermost annular groove with respect to the center of the holding member 16 may have the widest width. By increasing the volume of the inner recessed portion 40A, the depletion of the lubricant 42 (FIG. 2) can be suppressed. In addition, by reducing the volume of the outer concave portion 40B, excessive lubricant 42 (FIG. 2) can be suppressed, and the amount of lubricant 42 can be appropriately adjusted.

[Other embodiments]
An example of the embodiment of the present invention has been described above, but the embodiment of the present invention is not limited to the above, and can be modified in various ways without departing from the spirit of the present invention. Of course there is.

Although the depth d of the bottomed recess 40 is smaller than the thickness t of the first sliding member 14, the depth d may be equal to or greater than the thickness t. Further, although the depth d of the bottomed recess 40 is smaller than the width w of the bottomed recess 40, the depth d may be equal to or greater than the width w.

In the seismic isolation sliding bearing device 10, the first sliding member 14 slides on the lower structure 18, but the structure is reversed upside down so that the first sliding member 14 slides on the upper structure 20. may be

Instead of providing the second sliding member 24 , the other of the upper structure 20 and the lower structure 18 may be provided with a sliding surface for the first sliding member 14 .

Further, as shown in FIG. 11, the holding member 16 is provided with a bottomed recess 32 corresponding to the outer edge 14B of the first sliding member 14 and a bottomed recess 40 corresponding to the inside of the outer edge. may

Here, as shown in FIG. 12, outside the concave portion 16A of the holding member 16, the first sliding member 14 is accommodated in the concave portion 16A, and the first sliding member 14 is fitted along the side surface 14C of the first sliding member 14. A side wall surface of the holding member 16 forms an extending portion 16</b>B that extends to cover the outer peripheral portion of the sliding member 14 . In this specification, the extended state is defined as extended.

The extending portion 16B extends to the central portion in the thickness direction of the first sliding member 14, and the side surface 14C of the first sliding member 14 is surrounded over the entire circumference with the extending portion 16B in close contact. there is As a result, the first sliding member 14 can be prevented from separating from the holding member 16 when the holding member 16 moves horizontally in the lateral direction.

The bottomed concave portion 32 extends over the entire periphery of the portion of the holding member 16 corresponding to the outer edge portion 14B of the first sliding member 14, specifically, the outer edge portion of the top surface 16C of the concave portion 16A. there is The bottomed concave portion 32 constitutes a groove having a rectangular cross section extending along the inner side of the extending portion 16B.

As a result, the bottomed concave portion 32 is provided at a portion corresponding to the upper surface of the outer edge portion 14</b>B of the first sliding member 14 when the first sliding member 14 is accommodated in the holding member 16 . A bottomed portion as a deformation permitting portion so that when the first sliding member 14 deforms, the outer edge portion 14B of the first sliding member 14 can be deformed upward in a direction away from the sliding surface 24A of the second sliding member 24. A recess 32 is provided.

The holding member 16 is in surface contact with the first sliding member 14 in the top surface 16C of the recess 16A except for the bottomed recesses 32 and 40 . A vertical load applied from the holding member 16 to the first sliding member 14 is transmitted from this surface contact portion. As a result, transmission of load to the first sliding member 14 is suppressed at the outer edge portion 14B.

This deformation-allowing portion can be called, for example, a deformation-allowing structure or a pressure suppressing structure. In addition, since this deformation-allowing portion is constituted by the bottomed concave portion 32 recessed upward on the top surface 16C of the concave portion 16A, it has a step with respect to the top surface 16C. Therefore, the deformable portion can be called a stepped portion.

In addition, although the case where the cross-sectional shape of the bottomed recessed part 32 which comprises this deformation|transformation allowance part is formed in rectangular shape is mentioned as an example and demonstrated, it is not limited to this. For example, other cross-sectional shapes such as a semicircular cross-sectional shape and a triangular cross-sectional shape may be used.

As shown in FIG. 12, for example, when a vertical load from the upper structure 20 is transmitted to the first sliding member 14 and the first sliding member 14 is deformed, the outer edge 14B of the second sliding member 24 is deformed. It deforms upward away from the sliding surface 24A. The outer edge 14B of the first sliding member 14 is not deformed toward the sliding surface 24A to form a sharp edge (not shown). Therefore, compared to the case where the edge pushes the lubricant 42 on the outer periphery of the first sliding member 14 out of the range of movement of the first sliding member 14, as in the case where the edge is formed, the first sliding member 14 is Retention of lubricant in the returned position of member 14 is enabled.

This allows repeated use of the lubricant 42 that was maintained when the first sliding member 14 returned to its predetermined position. Therefore, even if the first sliding member 14 slides, it is possible to suppress the decrease in the usable lubricant.

Therefore, it is possible to maintain a predetermined thickness of the lubricant 42 and suppress an increase in the coefficient of friction without taking measures such as selection of specifications and types of the lubricant 42 and increasing the amount of the lubricant 42 retained. . As a result, the coefficient of friction of the first sliding member 14 can be stabilized, and the repetitive characteristics during sliding can be improved.

Also, the outer edge portion 14B of the first sliding member 14 deforms in a direction away from the sliding surface 24A. Therefore, it is also possible to form a deformed portion 14D that deforms upward toward the outermost edge of the first sliding member 14 at the outer edge portion 14B.

In such a case, since the corners can be rounded, the gap formed between the deformed portion 14D and the sliding surface 24A allows the lubricant to flow between the first sliding member 14 and the sliding surface 24A. 42 uptake can be facilitated. Therefore, an increase in the coefficient of friction between the first sliding member 14 and the sliding surface 24A can be suppressed.

Further, the holding member 16 is provided with an extending portion 16B extending along the side surface 14C of the first sliding member 14. As shown in FIG. Therefore, when the first sliding member 14 moves horizontally with respect to the sliding surface 24A due to the relative movement of the lower structure 18 and the upper structure 20 in the horizontal direction, the extending portion 16B moves toward the first sliding member. 14 can be brought into contact with the side surface 14C. Since the first sliding member 14 can be laterally supported by the extending portion 16B, the holding force of the holding member 16 for the first sliding member 14 during sliding can be increased.

Based on the structure of FIG. 12, as shown in FIGS. 13 and 14, the bottomed recess 40 (FIG. 12) may be omitted. In other words, only the bottomed concave portion 32 corresponding to the outer edge portion 14B of the first sliding member 14 may be formed on the top surface 16C of the holding member 16 . Further, in this example, a concave portion 14E is formed in a portion of the surface (slide surface 14A) of the first sliding member 14 on the side facing the lower structure 18. As shown in FIG. The recess 14E is, for example, an annular groove, but is not limited to this, and may be recesses of various shapes such as scattered recesses, recesses extending linearly or curvedly. Recess 14E may be applied to the structures shown in FIGS.

In this structure, a concave portion 14E is formed in the first sliding member 14, and the concave portion 14E serves as a dimple. Therefore, the lubricant 42 can be accumulated between the first sliding member 14 and the lower structure 18, specifically between the sliding surface 24A of the second sliding member 24 and the recess 14E.

Modifications of the recess 14E of the first sliding member 14 will be described with reference to FIGS. 15 to 19. FIG. In FIG. 15, a plurality of recesses 14E are provided. Further, the recess 14E becomes deeper or wider from the end of the sliding surface 14A of the first sliding member 14E toward the center CL (in the direction of the arrow IN). In this embodiment, the depth of the recess 14E increases and the width of the recess 14E increases from the end of the sliding surface 14A toward the center CL (in the direction of the arrow IN). Here, when there are three recesses 14E from the ends toward the center CL, the depths of the recesses 14E are da, db, and dc in order from the ends toward the center CL. Further, the widths of the recessed portion 14E are wa, wb, and wc in order from the end portion side toward the center CL side. Then, dc≧db≧da and wc≧wb≧wa. By increasing the volume of the recess 14 on the center CL side in this way, depletion of the lubricant 42 (FIG. 14) can be suppressed. The recess 14E at the center CL is a circular recess, and the width wc corresponds to the diameter of the circle.

In other words, in FIG. 15, the recess 14E becomes shallower or narrower from the center CL of the sliding surface 14A of the first sliding member 14 toward the end (in the direction of the arrow OUT). In this embodiment, the depth of the recessed portion 14E becomes shallower and the width of the recessed portion 14E becomes narrower from the center CL of the sliding surface 14A toward the end portion (in the direction of the arrow OUT). When the concave portion 14E is formed in an annular shape, the peripheral length of the concave portion 14E becomes longer and the volume increases toward the end portion of the sliding surface 14A. Therefore, by making the depth and width of the concave portion 14E shallower and narrower toward the end portion, excess lubricant 42 (FIG. 14) is suppressed and the amount of lubricant 42 is appropriately adjusted. be able to.

In FIG. 16, three or more recesses 14E are provided. The interval between adjacent concave portions 14E becomes narrower from the center CL of the sliding surface 14A of the first sliding member 14 toward the end portion (in the direction of the arrow OUT). Here, assuming that the intervals between the recesses 14E adjacent to each other are D2 and D1 in order from the center CL side toward the end portion side, D2>D1. As a result, since the density of the recesses 14E increases toward the end of the sliding surface 14A, it is possible to reduce the area through which the recesses 14E do not pass when the seismic isolation sliding bearing device 10 (FIG. 13) moves. As a result, the lubricant 42 (FIG. 14) can be spread over the end portion of the sliding surface 14A as well.

In FIG. 17, at least a portion of the recess 14E penetrates the first sliding member 14. In FIG. In other words, this recess 14E is formed as a through hole. By attaching the first sliding member 14 to the holding member 16 , the holding member 16 closes the side of the through hole opposite to the sliding surface 14</b>A. Thereby, the portion of the through hole functions as a concave portion. By forming the recess 14E as a through-hole, the capacity for containing the lubricant 42 can be increased. In addition, as compared with the case where the concave portion 14E has a bottom, the number of thinned portions is reduced, so cracking of the first sliding member 14 can be suppressed.

In FIG. 18, the width of the recess 14E narrows from the sliding surface 14A toward the bottom 14F of the recess 14E. The slip surface 14A side of the concave portion 14E serves as an inlet/outlet for the lubricant 42. As shown in FIG. Specifically, the wall portion connecting the sliding surface 14A and the bottom portion 14F of the recessed portion 14E is an inclined surface 14G that is inclined with respect to the thickness direction of the first sliding member 14. As shown in FIG. The distance between the inclined surfaces 14G opposed to each other in one concave portion 14E gradually increases from the bottom portion 14F toward the sliding surface 14A. By widening the width of the recess 14E on the side of the sliding surface 14A in this manner, the lubricant 42 is easily supplied from the recess 14E to the sliding surface 14A. Further, since the width w14 is narrowed toward the bottom 14F of the recess 14E, it is possible to adjust the amount of the lubricant 42 accumulated in the recess 14E so as not to be excessive.

As shown in FIG. 19, the portion where the recessed portion 14E opens to the sliding surface 14A of the first sliding member 14 may be chamfered to have an arcuate cross section (R chamfered portion 14R). This can prevent the first sliding member 14 from being caught when it slides on the second sliding member 24 (FIG. 13). On the other hand, the corner 14H of the bottom 14F of the recess 14E is not chamfered. Thereby, the volume of the recess 14E can be secured and the amount of the lubricant 42 stored in the recess 14E can be appropriately adjusted.

(Test example 1)
Friction with respect to the number of repetitions of sliding (sliding) of the first sliding member with respect to the second sliding member when using the holding member having the configuration shown in FIG. The amount of change in the coefficient was investigated.

In the holding member having the configuration shown in FIG. 3, two bottomed concave portions having a depth of d=3 mm and a width of w=12 mm are provided concentrically and annularly with the holding member.

The material of the first sliding member is a resin containing tetrafluoroethylene resin as a main component, and the material of the second sliding member is SUS404. The dimensions of the first sliding member and the second sliding member are as shown in Table 1. The amount of lubricant used is 2.5 g. Moreover, test conditions are as shown in Tables 2 and 3. The test results are as shown in FIG. From FIG. 5, when the holding portion is not provided with a bottomed recess (broken line), the amount of change in the coefficient of friction increases as the number of repetitions increases, but the holding portion is provided with a bottomed recess. In the case (solid line), it can be seen that even if the number of repetitions increases, the amount of change in the coefficient of friction is small.

(Test example 2)
In Tables 4 to 6, differences in coefficient of friction and amount of compressive strain due to differences in the composition of the first holding member were tested. Common test conditions are as follows.

Base resin: polytetrafluoroethylene (tetrafluoroethylene resin, PTFE)
<Friction test>
Tester: Dynamic friction tester Material of second sliding member: SUS304
Surface pressure: 20MPa
Speed: 100mm/s
Amplitude: 200mm
<Compressive strain amount>
Tester: Compression tester Surface pressure: 80MPa
Speed: 1.3mm/min
Specimen shape: diameter 30 mm x thickness 5 mm

Test conditions that are not common are as follows.
Lubricant: silicone oil

The target value of the coefficient of friction is 0.01 or less. The target value of the amount of compressive strain is 40% or less. It is desirable that both the target value of the coefficient of friction and the target value of the amount of compressive strain are satisfied. The amount of compressive strain was defined as ((d1-d2)/d1)×100(%). Here, d1 is the pre-test thickness of the first holding member, and d2 is the post-test thickness of the first holding member.

From Tables 4 and 5, regardless of whether the material blended in the first holding member is aromatic polyester or polyimide, when each blending ratio is 5 to 30 wt%, the coefficient of friction and the amount of compressive strain It was found that the target values were both achieved. Further, from Table 6, it was found that the target values of the coefficient of friction and the amount of compressive strain were achieved when the amount of graphite added was 20 wt% or less.

The disclosure of Japanese Patent Application No. 2017-131250 filed on July 4, 2017 and Japanese Patent Application No. 2018-14501 filed on January 31, 2018 is hereby incorporated by reference in its entirety. be taken into
All publications, patent applications and technical standards mentioned herein are to the same extent as if each individual publication, patent application and technical standard were specifically and individually noted to be incorporated by reference. incorporated herein by reference.

Claims (25)

a sliding bearing main body interposed between a lower structure and an upper structure disposed above the lower structure and fixed to one of the upper structure and the lower structure;
a first sliding member provided on the sliding bearing body and having a sliding surface against the other of the upper structure and the lower structure;
It is interposed between the sliding bearing main body and the first sliding member to hold the first sliding member, and when the first sliding member is deformed, the outer edge portion of the sliding member is extended to the upper structure and the lower structure. a holding member provided with a bottomed concave portion that is a groove at a position that allows deformation in a direction away from the other side of the body;
has
A seismic isolation sliding bearing device in which the width of the bottomed concave portion widens toward the surface of the holding member on the side of the first sliding member . 2. A seismic isolation sliding bearing device according to claim 1, wherein the depth of said bottomed recess is smaller than the thickness of said first sliding member. 3. The seismic isolation sliding bearing device according to claim 1, wherein the depth of the bottomed recess is smaller than the width of the bottomed recess. A plurality of bottomed recesses , including the bottomed recesses, are formed at a plurality of locations to allow the first sliding member to deform in a direction away from the other of the upper structure and the lower structure , and a plurality of the bottomed recesses. 4. The seismic isolation sliding bearing device according to any one of claims 1 to 3 , wherein at least a part of the depths of are different from each other. A plurality of bottomed recesses , including the bottomed recesses, are formed to allow the first sliding member to deform in a direction away from the other of the upper structure and the lower structure , and at least the bottomed recesses The seismic isolation sliding bearing device according to any one of claims 1 to 4 , wherein a part has grooves communicating with each other. 6. The seismic isolation sliding bearing device according to claim 5 , wherein the communicating groove has a depth shallower than that of the bottomed recess. A plurality of bottomed recesses, including the bottomed recesses, are formed to allow the first sliding member to deform in a direction away from the other of the upper structure and the lower structure, and the bottomed recesses The seismic isolation sliding bearing device according to any one of claims 1 to 6 , wherein the outer side of the holding member is arranged more densely than the inner side. A plurality of bottomed recesses, including the bottomed recesses, are formed at a plurality of locations to allow the first sliding member to deform in a direction away from the other of the upper structure and the lower structure,
The seismic isolation sliding bearing device according to any one of claims 1 to 7 , wherein the holding member has the bottomed concave portion at the center. A plurality of bottomed recesses, including the bottomed recesses, are formed at a plurality of locations to allow the first sliding member to deform in a direction away from the other of the upper structure and the lower structure,
9. The bottomed recess according to any one of claims 1 to 8 , wherein the bottomed recess is provided at a portion corresponding to the outer edge of the first sliding member and at a portion corresponding to the inner side of the outer edge. Seismic isolation sliding bearing device. A plurality of bottomed recesses, including the bottomed recesses, are formed at a plurality of locations to allow the first sliding member to deform in a direction away from the other of the upper structure and the lower structure,
The seismic isolation sliding bearing device according to any one of claims 1 to 9 , wherein the bottomed concave portion of the holding member has the shallowest depth or the narrowest width in the outermost portion. The seismic isolation sliding bearing device according to any one of claims 1 to 10 , wherein a concave portion is formed in a part of the sliding surface of the first sliding member. 12. The seismic isolation sliding bearing according to claim 11 , wherein a plurality of said recesses are provided, and the depth of said recesses increases or the width of said recesses increases toward the center from the end of said sliding surface of said first sliding member. Device. 12. The seismic isolation sliding bearing device according to claim 11 , wherein said recesses are provided at three or more locations, and the intervals between said recesses adjacent to each other become narrower from the center of said sliding surface of said first sliding member toward its ends. . 14. The seismic isolation sliding bearing device according to any one of claims 11 to 13 , wherein at least a part of said concave portion penetrates said first sliding member. The seismic isolation sliding bearing device according to any one of claims 11 to 14 , wherein the width of the recess decreases from the sliding surface of the first sliding member toward the bottom of the recess. The seismic isolation sliding bearing device according to any one of claims 11 to 15 , wherein a portion where the recess opens onto the sliding surface of the first sliding member is chamfered to have an arcuate cross section. A second sliding member having a sliding surface for the first sliding member is provided on the other of the upper structure and the lower structure,
The seismic isolation sliding bearing device according to any one of claims 1 to 16 , wherein a lubricant is arranged between the first sliding member and the second sliding member. The seismic isolation sliding bearing device according to any one of claims 1 to 17 , wherein the first sliding member is a tetrafluoroethylene resin composition containing aromatic polyester or polyimide. The seismic isolation sliding bearing device according to any one of claims 1 to 17 , wherein the first sliding member is a tetrafluoroethylene resin composition containing 5 to 30 wt% of aromatic polyester. The seismic isolation sliding bearing device according to any one of claims 1 to 17 , wherein the first sliding member is a polytetrafluoroethylene resin composition containing 5 to 30 wt% of polyimide. 21. The shield according to any one of claims 18 to 20 , wherein the first sliding member further contains one or more of carbon fiber, graphite, glass fiber, molybdenum disulfide, potassium titanate, and bronze. Seismic sliding bearing device. 21. The first sliding member further contains one or more of carbon fiber, graphite, glass fiber, molybdenum disulfide, potassium titanate, and bronze in an amount exceeding 0 and 20 wt % or less. 1. A seismic isolation sliding bearing device according to item 1. The seismic isolation sliding bearing device according to any one of claims 18 to 22 , wherein the first sliding member has a coefficient of friction of 0.01 or less when the surface pressure is 20 MPa. The seismic isolation sliding bearing device according to any one of claims 18 to 22 , wherein the compressive strain amount when the first sliding member has a surface pressure of 80 MPa is 40% or less. 25. The seismic isolation sliding bearing device according to any one of claims 1 to 24 , wherein a concave portion is formed in a part of the surface of the first sliding member facing the lower structure.

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