Friction damper

Abstract

Provided is a friction damper that is disposed between a pair of members which relatively move in a prescribed direction, and that prevents the relative movement via frictional force between pressure-contact plates that slide together with the relative movement. The friction damper comprises: a first pressure-contact plate that is provided integrally with one member among the pair of members; a pair of second pressure-contact plates that are provided integrally with the other member among the pair of members, and that sandwich the first pressure-contact plate from both sides with a prescribed pressure-contact force; a third pressure-contact plate of one side that is provided integrally with the one member and that, together with the first pressure-contact plate, sandwiches the second pressure-contact plate, among the pair of second pressure-contact plates, which is on one side from said one side with a prescribed pressure-contact force; a third pressure-contact plate of another side that is provided integrally with the one member and that, together with the first pressure-contact plate, sandwiches the second pressure-contact plate, among the pair of second pressure-contact plates, which is on the other side from said other side with a prescribed pressure-contact force; and a first fastening member that is provided inserted into a through hole of the first pressure-contact plate, through holes of the pair of second pressure-contact plates, and through holes of the third pressure-contact plates of the one side and the other side, and that causes the first pressure-contact plate, the pair of second pressure-contact plates, and the third pressure-contact plates of the one-side and the other-side to be in pressure-contact in a plate-thickness direction orthogonal to the facing surfaces of the first pressure-contact plate and the pair of second pressure-contact plates. The through holes of the pair of second pressure-contact plates are long holes. The through hole of the first pressure-contact plate and the through holes of the third pressure-contact plates of the one-side and the other-side are bolt holes. The first fastening member comprises a bolt that is inserted into the long holes and the bolt holes, a nut that is screwed together with the bolt, and a pipe that the bolt is inserted into and that is accommodated in the long holes and the bolt holes. Axial force acts on the friction damper in a prescribed direction, and the pipe, which contacts the inner surfaces of the long holes in the minor-axis direction, inhibits buckling in an in-surface direction of a sliding surface between the sliding pressure-contact plates.

Description

Friction damper

[0001] The present invention relates to a friction damper.

[0002] Friction dampers are known that are disposed between a pair of members that move relative to each other in a predetermined direction to suppress the relative movement. For example, in the friction damper disclosed in Patent Document 1, friction dampers are provided on the flange and web of a brace (H-shaped steel) of a building frame, and are capable of responding not only to axial forces along the brace span direction but also to stresses (bending moments) in a direction intersecting the span direction.

[0003] Japanese Patent Application Laid-Open No. 2015-113955

[0004] However, sometimes friction dampers are not installed on the flanges, but only on the webs. In this case, if the bending moment exceeds the design assumption, the bolts inserted into the webs (long holes) of the friction dampers come into contact with the inner surface of the long hole in the minor axis direction, providing resistance to prevent buckling. However, there is a risk of damage to the bolts or buckling of the components that make up the brace. This issue is also true for friction dampers with four or more sliding surfaces.

[0005] The present invention has been made in consideration of the above-mentioned problems, and its purpose is to suppress buckling without affecting the bolt, even in a friction damper with four or more sliding surfaces.

[0006] The main invention for achieving the above object is a friction damper that is disposed between a pair of members that move relatively in a predetermined direction, and that suppresses the relative movement by frictional force between pressure contact plates that slide in association with the relative movement, comprising: a first pressure contact plate that is provided integrally with one of the pair of members; a pair of second pressure contact plates that are provided integrally with the other of the pair of members and that sandwich the first pressure contact plate from both sides with a predetermined pressure contact force; a third pressure contact plate that is provided integrally with one of the members and that sandwiches the second pressure contact plate on one side of the pair of second pressure contact plates from the one side with the predetermined pressure contact force between the first pressure contact plate; a third pressure contact plate that is provided integrally with one of the members and that sandwiches the second pressure contact plate on the other side of the pair of second pressure contact plates from the other side with the predetermined pressure contact force between the first pressure contact plate; and a first fastening member that is inserted into the through hole of the first press-fit plate and the through holes of the third press-fit plates on the one side and the other side, and presses the first press-fit plate, the pair of second press-fit plates, and the third press-fit plates on the one side and the other side together in a plate thickness direction perpendicular to the opposing surfaces of the first press-fit plate and the pair of second press-fit plates, wherein the through holes of the pair of second press-fit plates are elongated holes, and the through holes of the first press-fit plate and the through holes of the third press-fit plates on the one side and the other side are bolt holes, and the first fastening member has a bolt inserted into the elongated hole and the bolt hole, a nut threaded onto the bolt, and a pipe through which the bolt is inserted and which is housed in the elongated hole and the bolt hole, and an axial force acts on the friction damper in the predetermined direction, and the pipe, which is in contact with the inner surface in the short diameter direction of the elongated hole, suppresses in-plane buckling of the sliding surfaces between the sliding press-fit plates.

[0007] Other features of the present invention will become apparent from the following description and drawings.

[0008] According to the present invention, even in the case of a friction damper with four or more sliding surfaces, buckling can be suppressed without affecting the bolt.

[0009] 1A and 1B are schematic explanatory diagrams of a friction damper 10 according to the present embodiment. FIG. 2A is a plan view of a brace fragment 5, and FIG. 2B is a cross-sectional view of the brace fragment 5. FIG. 3A is a plan view of a connecting member 7, and FIG. 3B is a cross-sectional view of the connecting member 7. FIG. 4A is a plan view of a splicing member 8, and FIG. 4B is a cross-sectional view of the splicing member 8. FIG. 1B is a cross-sectional view of a first fastening member 20a and its periphery (cross-sectional view A-A in FIG. 1). FIG. 1C is a cross-sectional view of a second fastening member 20b and its periphery (cross-sectional view B-B in FIG. 1). FIG. 1D is a cross-sectional view of a first fastening member 20a and its periphery in a friction damper 10A according to a first modified example. FIG. 1E is a cross-sectional view of a first fastening member 20a and its periphery in a friction damper 10B according to a second modified example. FIG. 1F is a cross-sectional view of a first fastening member 20a and its periphery in a friction damper 10C according to a third modified example. FIG. 1G is a cross-sectional view of a first fastening member 20a and its periphery in a friction damper 10D according to a fourth modified example. FIG. 1H is a cross-sectional view of a first fastening member 20a and its periphery in a friction damper 10E according to a fifth modified example. 10A and 10B are cross-sectional views of the periphery of a first fastening member 20a in a friction damper 10F of a sixth modified example, and cross-sectional views of the periphery of a first fastening member 20a in a friction damper 10G of a seventh modified example.

[0010] At least the following points will become clear from the description and drawings to be described later.

[0011] (Aspect 1) A friction damper is disposed between a pair of members that move relatively in a predetermined direction, and suppresses the relative movement by frictional force between pressure contact plates that slide in association with the relative movement, the friction damper comprising: a first pressure contact plate that is integral with one of the pair of members; a pair of second pressure contact plates that are integral with the other of the pair of members and that sandwich the first pressure contact plate from both sides with a predetermined pressure contact force; a third pressure contact plate that is integral with one of the members and that sandwiches the second pressure contact plate on one side of the pair of second pressure contact plates from the one side with the predetermined pressure contact force between the first pressure contact plate; a third pressure contact plate that is integral with one of the members and that sandwiches the second pressure contact plate on the other side of the pair of second pressure contact plates from the other side with the predetermined pressure contact force between the first pressure contact plate; a first fastening member that is inserted into the through holes of the third press-fit plates on one side and the other side, and presses the first press-fit plate, the pair of second press-fit plates, and the third press-fit plates on one side and the other side together in a plate thickness direction perpendicular to the opposing surfaces of the first press-fit plate and the pair of second press-fit plates, wherein the through holes of the pair of second press-fit plates are elongated holes, and the through holes of the first press-fit plate and the through holes of the third press-fit plates on the one side and the other side are bolt holes, and the first fastening member has a bolt inserted into the elongated hole and the bolt hole, a nut threaded onto the bolt, and a pipe through which the bolt is inserted and which is housed in the elongated hole and the bolt hole, wherein an axial force acts on the friction damper in the predetermined direction, and the pipe, which is in contact with the inner surface of the elongated hole in the minor diameter direction, suppresses in-plane buckling of the sliding surfaces between the sliding press-fit plates.

[0012] According to the friction damper of aspect 1, even if there are four or more sliding surfaces, when an axial force acts in a predetermined direction, buckling in the transverse direction can be suppressed by bringing the pipe into contact with the inner surface of the long hole in the minor axis direction. Furthermore, by providing the pipe, the bolt does not come into contact with the inner surface of the long hole in the minor axis direction, so the important bolt that bears the axial force can be protected (the bolt can be prevented from being damaged).

[0013] (Aspect 2) In the friction damper according to aspect 1, it is desirable that the pipe has a length that spans two or more pressure plates that form at least one of the four sliding surfaces.

[0014] The friction damper of aspect 2 suppresses buckling without affecting the bolts, and allows the pipes to be placed only where necessary, thereby shortening the length of the pipes, which makes it easier to assemble the friction damper.

[0015] (Aspect 3) In the friction damper according to aspect 1, it is preferable that the pipe is a long pipe having a length spanning from the third press-contact plate on one side to the third press-contact plate on the other side.

[0016] According to the friction damper of aspect 3, it is possible to select a second pressure contact plate that moves (rotates) along the inner surface of the long hole after contact with the pipe, thereby increasing the degree of freedom in designing the second pressure contact plate.

[0017] (Aspect 4) In the friction damper according to aspect 1, it is preferable that the pipe is a short pipe having a length spanning from the second press-contact plate on one side to the second press-contact plate on the other side.

[0018] According to the friction damper of aspect 4, it is possible to select a second pressure plate that moves (rotates) along the inner surface of the long hole after contact with the pipe, which increases the design freedom of the second pressure plate and also allows the length of the pipe to be shortened.

[0019] (Aspect 5) In the friction damper according to aspect 4, it is preferable that the diameter of the through hole of the other third press-connected plate is smaller than the outer diameter of the pipe.

[0020] According to the friction damper of aspect 5, the number of parts can be reduced.

[0021] (Aspect 6) In the friction damper according to aspect 1, it is preferable that the pipe is a split pipe.

[0022] According to the friction damper of aspect 6, the pipe can be brought into contact with the second pressure contact plate quickly.

[0023] (Aspect 7) In the friction damper according to aspect 1, it is preferable that the pipe is a continuous pipe formed by connecting a plurality of the split pipes.

[0024] According to the friction damper of aspect 7, the pipe can be brought into contact with the second pressure contact plate quickly.

[0025] (Aspect 8) In the friction damper described in Aspect 1, it is desirable that the first pressure-welded plate is a web of an H-shaped steel, the pair of second pressure-welded plates are webs of a C-shaped steel, and the pair of flanges of the C-shaped steel face each other so as not to come into contact with the inside of the pair of flanges of the H-shaped steel.

[0026] According to the friction damper of aspect 8, the pipe comes into contact with the inner surface of the short diameter of the slot (the web of the H-beam) before the flange of the H-beam and the flange of the C-beam come into contact, thereby preventing the flange of the H-beam and the flange of the C-beam from coming into contact (reducing damage to the flanges).

[0027] (Aspect 9) The friction damper according to any one of aspects 1 to 8 preferably has a second fastening member that is the first fastening member excluding the pipe, the first fastening member being provided as a pair between the pair of members, and the second fastening member being provided between the pair of first fastening members between the pair of members.

[0028] According to the friction damper of aspect 9, the number of pipes required can be reduced. Also, assembly is easier than when pipes are provided for all parts.

[0029] Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. The same or equivalent components, members, etc. shown in the drawings will be designated by the same reference numerals, and redundant descriptions will be omitted where appropriate.

[0030] ===Present Embodiment=== <<About the Friction Damper>> The friction damper of this embodiment is a brace-type friction damper that is incorporated into a brace connecting both ends of a diagonal line (column-beam joint) in a column-beam frame (building frame) surrounded by columns and beams.

[0031] Such a brace-type friction damper suppresses vibrations by utilizing the frictional force between the pressure-welded plates that occurs as the brace moves relative to one another in the span direction (in this embodiment, the relative movement of a pair of brace segments 5, 6, which will be described later).

[0032] However, when an axial force along the brace span direction acts on such a friction damper, stress may act not only in the axial force but also in the perpendicular direction (the in-plane direction of the opposing surfaces of the pressure-welded plates).If a friction damper is provided only on the web of the brace (H-beam), the above stress may cause the bolts inserted into the web to come into contact with the web and be damaged, or the components that make up the brace may buckle.

[0033] Therefore, in this embodiment, buckling can be suppressed without affecting the bolt.

[0034] <<Configuration of Friction Damper 10 >> Hereinafter, the friction damper 10 of this embodiment will be described with reference to the drawings.

[0035] Fig. 1 is a schematic explanatory diagram of a friction damper 10 of this embodiment. As shown in Fig. 1, the friction damper 10 of this embodiment is a brace-type friction damper incorporated into a brace of a column-beam frame 1 (building frame) surrounded by a column 1a erected in the vertical direction and a beam 1b extending in the horizontal direction.

[0036] Hereinafter, the brace spanning direction in Fig. 1 is referred to as the X direction, and the direction perpendicular (intersecting) to the X direction in the structural plane of the beam-column frame 1 is referred to as the Y direction. The direction perpendicular to the X and Y directions (the direction perpendicular to the paper surface in Fig. 1) is referred to as the Z direction. The X direction corresponds to the "predetermined direction," the Y direction corresponds to the "intersecting direction," and the Z direction corresponds to the "plate thickness direction." The plate thickness direction is also the direction perpendicular to the opposing surfaces of the web 5w of the brace segment 5 (described later) and the web 7w of the connecting member 7 (described later).

[0037] As shown in Fig. 1, a pair of gusset plates 2 are provided at both diagonal ends (column-beam joints) of the column-beam frame 1. The gusset plates 2 are fixed (joined) to the column 1a and the beam 1b by, for example, welding. A pin joint structure 3 is rotatably joined (pin-jointed) to each of the pair of gusset plates 2. A brace 4 is provided between the pair of pin joint structures 3 at the diagonal positions of the column-beam frame 1.

[0038] The brace 4 is mainly composed of H-shaped steel, which is divided at an appropriate position at a predetermined distance from each other to form a pair of brace segments 5, 6. The pair of brace segments 5, 6 corresponds to a "pair of members." The brace segments 5, 6 are each fixed (joined) to the pin joint structure 3, which allows them to move relative to each other in the X direction (predetermined direction).

[0039] The brace pieces 5, 6 are connected by a connecting member 7. The connecting member 7 in this embodiment is made of C-section steel, as will be described later.

[0040] Furthermore, a splice member 8 is spliced ​​to the brace piece 5. The splice member 8 in this embodiment is made of flat steel as will be described later.

[0041] The friction damper 10 of this embodiment is incorporated into the brace 4 and includes brace pieces 5 and 6, a connecting member 7, a splice member 8, a first fastening member 20a, and a second fastening member 20b. A plurality of second fastening members 20b (three in this case) are arranged side by side in the X direction, and a pair (two) of first fastening members 20a are arranged so as to sandwich the plurality (three in this case) of second fastening members 20b in the X direction.

[0042] In addition, in this embodiment, the friction damper 10 has four or more sliding surfaces (four surfaces in this example), as will be described later. For example, compared to a case where the number of sliding surfaces is three or less (for example, two surfaces), increasing the number of sliding surfaces by increasing the number of pressure contact plates increases the number of sliding contact plates and increases the frictional force, thereby more reliably damping vibrations. Furthermore, by increasing the number of pressure contact plates and the number of sliding surfaces, it is also possible to vary the frictional force gradually between the sliding surfaces.

[0043] The configuration of each of these components will be described below.

[0044] Fig. 2A is a plan view of the brace fragment 5, and Fig. 2B is a cross-sectional view of the brace fragment 5. Fig. 3A is a plan view of the connecting member 7, and Fig. 3B is a cross-sectional view of the connecting member 7. Fig. 4A is a plan view of the splicing member 8, and Fig. 4B is a cross-sectional view of the splicing member 8. Fig. 5 is a cross-sectional view of the periphery of the first fastening member 20a (cross-sectional view A-A in Fig. 1). Fig. 6 is a cross-sectional view of the periphery of the second fastening member 20b (cross-sectional view B-B in Fig. 1).

[0045] <Regarding the Brace Fragments 5, 6> The brace fragment 5 (corresponding to one of the members) is a steel material (H-shaped steel) with an H-shaped cross section, in which a pair of flanges 5 f are connected at approximately the center by a web 5 w, as shown in Fig. 2B . In this embodiment, the brace fragment 5 is arranged so that the web 5 w of the brace fragment 5 is along the structural surface of the beam-column frame 1.

[0046] 2A , a plurality of bolt holes 5a, 5b (through holes) penetrating in the Z direction are provided in the web 5w of the brace segment 5 with a gap in the X direction. The bolt holes 5a are provided corresponding to first fastening members 20a (described later), and the bolt holes 5b are provided corresponding to second fastening members 20b (described later). Specifically, a pair (two) of bolt holes 5a are provided on the outsides of a plurality (three in this embodiment) of bolt holes 5b aligned in the X direction, sandwiching them.

[0047] Bolt hole 5b is formed with a diameter (diameter) slightly larger than the diameter of bolt 21 (described later). Bolt hole 5a is formed with a diameter even larger than bolt hole 5b (and bolt 21) to accommodate a pipe 27 (described later) between bolt hole 5a and bolt 21. However, bolt hole 5a may not accommodate pipe 27, as in a friction damper 10C ( FIG. 9 ) of a third modified example described later. In this case, the diameter of bolt hole 5a may be the same as the diameter of bolt hole 5b (a diameter slightly larger than the diameter of bolt 21).

[0048] 2A, the web 5w of the brace segment 5 has a bolt hole 5c formed therethrough in the Z direction. The bolt hole 5c is a hole for inserting a bolt 30 (see FIG. 1) that joins the brace segment 5 and the splice member 8. The brace segment 5 (web 5w) and the splice member 8 can be joined by inserting the bolt 30 through the bolt hole 5c of the brace segment 5 and the bolt hole 8c (see FIG. 4A) of the splice member 8 and tightening it with a nut (not shown). Note that the method for joining the brace segment 5 and the splice member 8 is not limited to this, and they may also be joined by welding, for example.

[0049] As shown in FIG. 1 , one end of the brace piece 5 (the end on the column-beam joint side) is fixed (joined) to the pin joint structure 3 .

[0050] The brace segment 6 (corresponding to the other member) is also a steel material (H-shaped steel) having the same cross-sectional shape as the brace segment 5, and has a pair of flanges 6 f and a web 6 w. The brace segment 6 in this embodiment is shorter in length in the X direction than the brace segment 5, and the web 6 w of the brace segment 6 has bolt holes (not shown) for joining the connecting member 7, which correspond to bolt holes 7 b (described later) in the web 7 w of the connecting member 7.

[0051] As shown in FIG. 1 , one end of the brace fragment 6 (the end on the beam-column joint side) is fixed (joined) to the pin joint structure 3 , similar to the brace fragment 5 .

[0052] As shown in Figures 5 and 6, friction plates 5m are immovably fixed to both sides in the Z direction of the web 5w of the brace segment 5. Furthermore, as will be described later, sliding plates 7s (e.g., stainless steel plates) are immovably fixed to the surfaces of the webs 7w of the connecting members 7 arranged on both sides of the web 5w, facing the friction plates 5m. The relationship between the friction plates 5m and the sliding plates 7s may be reversed. That is, a sliding plate may be provided on the web 5w of the brace segment 5, and a friction plate may be provided on the web 7w of the connecting member 7.

[0053] <Regarding the Connecting Member 7> As shown in FIG. 3B, the connecting member 7 is a steel material (C-beam) having a generally U-shaped cross section, and has a pair of flanges 7f and a web 7w (corresponding to a second pressure-welded plate).

[0054] The connecting member 7 spans between the brace segments 5 and 6 that make up the brace 4. The length (width) of the connecting member 7 in the Y direction is shorter than the length (the distance between the pair of flanges 5f) of the web 5w of the brace segment 5 in the Y direction. This allows the web 7w of the connecting member 7 to be arranged so as to overlap the web 5w of the brace segment 5, as shown in Figures 1, 5, and 6. The same applies to the relationship between the brace segments 6 and the connecting member 7.

[0055] The connecting member 7 is joined to the brace segment 6 by bolts 40 or the like shown in FIG. 1 . Specifically, the web 7w of the connecting member 7 is joined to the web 6w of the brace segment 6, and the flange 7f of the connecting member 7 is not joined to the flange 6f of the brace segment 6. This reduces the effort and cost and enables efficient joining. However, the flange 7f of the connecting member 7 and the flange 6f of the brace segment 6 may also be joined. Furthermore, the connecting member 7 is provided so as to be displaceable relative to the brace segment 5 and the splice member 8.

[0056] Furthermore, as shown in FIG. 3A, the web 7w (corresponding to the second pressure contact plate) of the connecting member 7 of this embodiment is formed with a long hole 7a (through hole) that penetrates in the Z direction and is long in the X direction.

[0057] The long diameter (here, the length in the X direction) of the elongated hole 7a is longer than the length in the X direction of the bolts 21 (described later) provided on each of the multiple fastening members (specifically, two first fastening members 20a and three second fastening members 20b) described later. That is, in this embodiment, multiple fastening members (two first fastening members 20a and three second fastening members 20b) are inserted into the elongated hole 7a that is long in the X direction. However, if the relative movement amount in the brace 4's spanning direction (X direction) (in this embodiment, the relative movement amount between the pair of brace segments 5 and 6) is not large, the elongated hole 7a (through hole) may be separated for each fastening member. That is, a separate elongated hole 7a may be provided for each fastening member. Furthermore, the short diameter (length in the Y direction) of the elongated hole 7a is larger than the diameter of the bolt 21 and also larger than the outer diameter of the pipe 27 (described later). Note that, in this embodiment, the diameter of the bolt 21 refers to the diameter of the shank of the bolt 21, excluding the head.

[0058] As shown in FIGS. 5 and 6, the connecting members 7 are provided on both sides of the web 5w of the brace piece 5 (one pair) so as to sandwich the web 5w.

[0059] As shown in Figures 5 and 6, sliding plates 7s (e.g., stainless steel plates) are immovably fixed to both sides of the web 7w of the connecting member 7 in the Z direction. Furthermore, as will be described later, friction plates 8m are immovably fixed to the surfaces of the pressing members 8 arranged on both sides of the web 7w, facing the sliding plates 7s. The relationship between the sliding plates 7s and the friction plates 8m may be reversed. That is, the friction plates may be provided on the web 7w of the connecting member 7, and the sliding plates may be provided on the pressing members 8.

[0060] <Regarding the Press-Welding Member 8> The press-welding member 8 (corresponding to the third press-welding plate) is a steel material (flat steel) having a substantially plate-shaped cross section, as shown in FIG. 4B.

[0061] The splice member 8 is bridged between the brace segment 5 and the connecting member 7 that make up the brace 4. The length (width) of the splice member 8 in the Y direction is shorter than the length (the distance between the pair of flanges 7f) of the web 7w of the connecting member 7 in the Y direction. This allows the splice member 8 to be arranged so that it overlaps the web 7w of the connecting member 7, as shown in Figures 1, 5, and 6. As described above, the length (width) of the connecting member 7 in the Y direction is shorter than the length (the distance between the pair of flanges 5f) of the web 5w of the brace segment 5, and therefore the same applies to the relationship between the splice member 8 and the brace segment 5.

[0062] The splicing members 8 are joined to the webs 5w of the brace segments 5 by bolts 30 or the like shown in Figure 1. The splicing members 8 are provided so as to be displaceable relative to the brace segments 6 and the connecting members 7.

[0063] 4A , the splice member 8 is provided with a plurality of bolt holes 8a, 8b (through holes) that penetrate in the Z direction and are spaced apart in the X direction. The bolt hole 8a is provided to correspond to a first fastening member 20a (described later), and the bolt hole 8b is provided to correspond to a second fastening member 20b (described later). Specifically, a pair (two) of bolt holes 8a are provided on the outside of a plurality (three in this embodiment) of bolt holes 8b aligned in the X direction, sandwiching them.

[0064] The bolt hole 8b is formed with a diameter (diameter) slightly larger than the diameter of the bolt 21 (described later). The bolt hole 8a is formed with a diameter even larger than the bolt hole 8b (and the bolt 21) to accommodate a pipe 27 (described later) between the bolt hole 8a and the bolt 21. However, there are cases where the bolt hole 8a does not accommodate the pipe 27, such as in a friction damper 10E ( FIG. 11 ) of a fifth modified example, a friction damper 10F ( FIG. 12 ), and a friction damper 10G ( FIG. 13 ) of a seventh modified example, which will be described later. In such cases, the diameter of the bolt hole 8a may be the same as the diameter of the bolt hole 8b (a diameter slightly larger than the diameter of the bolt 21) and may be smaller than the outer diameter of the pipe 27.

[0065] 4A, the splicing member 8 has a bolt hole 8c formed therethrough in the Z direction. The bolt hole 8c is a hole for inserting a bolt 30 (see FIG. 1) that joins the brace segment 5 and the splicing member 8. The brace segment 5 (web 5w) and the splicing member 8 can be joined by inserting the bolt 30 through the bolt hole 5c (see FIG. 2A) of the brace segment 5 and the bolt hole 8c of the splicing member 8 and tightening it with a nut (not shown). Note that the method for joining the brace segment 5 and the splicing member 8 is not limited to this, and they may also be joined by welding, for example.

[0066] As shown in FIGS. 5 and 6, the splicing members 8 are provided on both sides of the web 7w of the connecting member 7 (a pair) so as to sandwich the web 7w.

[0067] A friction plate 8m is immovably fixed to the surface of each of the pair of splicing members 8 facing the web 7w of the connecting member 7. As described above, a sliding plate 7s is immovably fixed to the surface of the web 7w of the connecting member 7 facing the friction plate 8m.

[0068] <Regarding Fastening Members> (First Fastening Member 20a) As shown in FIG. 5, the first fastening member 20a has a bolt 21, a nut 22, a washer 23, a disc spring 24, a guide bush 25, a splice plate 26, and a pipe 27.

[0069] The bolts 21 are, for example, high-strength bolts, and are inserted through the bolt holes 8a (through holes) of the pair of splice members 8, the elongated holes 7a (through holes) of the webs 7w of the pair of connecting members 7, and the bolt holes 5a (through holes) of the webs 5w of the brace segments 5. The bolts 21 are also inserted through the washers 23, the splice plates 26, and the guide bushes 25.

[0070] A nut 22 is threaded onto the tip side of the bolt 21. With this bolt 21 and nut 22, the web 5w of the brace segment 5 is sandwiched between the webs 7w of the pair of connecting members 7, and the webs 7w of the pair of connecting members 7 are further fastened in a sandwiched state between the pair of splicing members 8, thereby applying a pressing force (corresponding to a predetermined pressing force) for sandwiching in the plate thickness direction (Z direction).

[0071] This pressing force causes the friction plate 5m of the web 5w of the brace segment 5 to come into contact with the sliding plate 7s on the side of the web 7w of the connecting member 7 that faces the web 5w. Also, the sliding plate 7s on the side of the web 7w of the connecting member 7 that faces the splice member 8 comes into contact with the friction plate 8m of the splice member 8. Therefore, when the connecting member 7 slides against the brace segment 5 and the splice member 8, a friction force corresponding to the pressing force is generated. This friction force acts as a damping force for vibration of the beam-column frame 1. The magnitude of the pressing force is stabilized by the elastic force of the disc spring 24 interposed between the nut 22 and the splice plate 26.

[0072] In this embodiment, the disc spring 24 (and guide bush 25) and the like are provided on one side of the web 5w of the brace piece 5, but this is not limiting, and a disc spring, guide bush, and the like may also be provided on the other side of the web 5w (the side where the washer 23 is arranged). In this case, the pressing force can be applied more effectively.

[0073] The pipe 27 is a cylindrical metal member. In the friction damper 10 of this embodiment, the pipe 27 is provided around the bolt 21 between the washer 23 and the splice plate 26, and is housed in the bolt hole 5 a (through hole) in the web 5 w of the brace segment 5, the elongated hole 7 a (through hole) in the web 7 w of the pair of connecting members 7, and the bolt hole 8 a (through hole) in the pair of splice members 8.

[0074] In other words, the length of the pipe 27 in this embodiment is equal to or less than the total thickness of all the pressure contact plates (the web 5w (including the friction plate 5m), the pair of webs 7w (including the sliding plates 7s), and the pair of splice members 8 (including the friction plates 8m)) in the first fastening member 20a. This allows the pipe 27 to be arranged only in the portion necessary to suppress buckling (the length of the pipe 27 can be shortened), making assembly easier. Specifically, in the friction damper 10 of this embodiment shown in FIG. 5, the pipe 27 is a long pipe whose length spans from the splice member 8 (third pressure contact plate) on one side in the Z direction to the splice member 8 (third pressure contact plate) on the other side in the Z direction. This makes it possible to select the web 7w of the connecting member 7 that moves (rotates) along the inner surface 7c of the elongated hole 7a after contact with the pipe 27, thereby increasing the degree of freedom in designing the web 7w of the connecting member 7. However, the length of the pipe in the Z direction can be changed as needed as long as it is long enough to span two or more pressure plates that form at least one of the four sliding surfaces. The number of pipes housed in each through hole can also be changed as needed (separate pipes can also be used). This will be described in detail with reference to a modified friction damper described later.

[0075] The inner diameter of the pipe 27 is larger than the diameter of the bolt 21. A gap d1 between the outer peripheral surface of the pipe 27 and the inner surface 7c of the long hole 7a in the minor axis direction (inner surface in the Y direction) is smaller than a gap d2 between the flange 5f of the brace piece 5 and the flange 7f of the connecting member 7.

[0076] (Second Fastening Member 20b) As shown in FIG. 6 , the second fastening member 20b includes a bolt 21, a nut 22, a washer 23, a disc spring 24, a guide bush 25, and a splice plate 26. That is, the second fastening member 20b has a configuration in which the pipe 27 of the first fastening member 20a is removed. The bolt 21 of the second fastening member 20b is inserted through the bolt holes 8b (through holes) of the pair of splice members 8, the elongated holes 7a (through holes) of the webs 7w of the pair of connecting members 7, and the bolt holes 5b (through holes) of the webs 5w of the brace segments 5. Furthermore, since the second fastening member 20b does not include the pipe 27, the gap d1′ between the outer peripheral surface of the bolt 21 and the inner surface 7c (inner surface in the Y direction) of the elongated hole 7a shown in FIG. 6 is larger than the gap d1 between the outer peripheral surface of the pipe 27 and the inner surface 7c (inner surface in the Y direction) of the elongated hole 7a in the minor axis direction.

[0077] <<Operation of Friction Damper 10 >> Next, the operation of the friction damper 10 of this embodiment will be described.

[0078] When an axial force (tensile force or compressive force) in the X direction acts on the beam-column frame 1 due to an external force such as an earthquake, the brace segments 5 and 6 connected by this friction damper 10 move relative to each other in the X direction. In this case, the brace segments 5 and the splice members 8 fixed to (integrally provided with) the brace segments 5 move relative to the connecting member 7 fixed to (integrally provided with) the brace segments 6, and the bolts 21 of each fastening member (first fastening member 20 a, second fastening member 20 b) move in the longitudinal direction (X direction) of the elongated hole 7 a together with the brace segments 5 and the splice members 8. In other words, the web 5 w and splice members 8 of the brace segments 5 and the web 7 w of the connecting member 7 slide along the longitudinal direction while being pressed against each other by the fastening members (first fastening member 20 a and second fastening member 20 b). At this time, frictional forces are generated between the friction plate 5m and the sliding plate 7s on the side facing the web 5w, and between the sliding plate 7s on the side facing the attachment member 8 and the friction plate 8m, thereby suppressing vibrations.

[0079] As mentioned above, when an axial force (compressive force) acts on the brace 4 and the friction damper 10 in the X direction (the brace span direction), not only the axial force but also a bending moment (shear force) may act in a direction intersecting the X direction (the Y direction or the Z direction). The friction damper 10 in this embodiment is provided only on the web 5w of the brace segment 5 (H-shaped steel), but it can also suppress buckling in the Y direction and the Z direction. In this embodiment, as will be described later, the pipe 27 in contact with the inner surface 7c in the minor diameter direction of the long hole 7a of the web 7w of the connecting member 7 suppresses in-plane buckling of the sliding surface between the sliding pressure-welded plates.

[0080] <Regarding the Y direction> When the web 5w and splice member 8 of the brace segment 5 and the web 7w of the connecting member 7 are displaced relative to each other in the Y direction, for example, in Figure 5, the pipe 27 comes into contact with the inner surface of the bolt hole 5a of the brace segment 5 and the inner surface of the bolt hole 8a of the splice member 8. As the displacement progresses further, the brace segment 5 and the pair of splice members 8 and the pair of connecting members 7 move relative to each other in the Y direction. At this time, frictional forces are generated between the friction plate 5m and the sliding plate 7s facing the web 5w, and between the sliding plate 7s facing the splice member 8 and the friction plate 8m.

[0081] As described above, in the friction damper 10 of this embodiment, the gap d1 between the inner surface 7c in the minor diameter direction of the elongated hole 7a and the outer peripheral surface of the pipe 27 shown in FIG. 5 is smaller than the gap d2 between the flange 5f of the brace segment 5 and the flange 7f of the connecting member 7. Therefore, when the brace segment 5 and the splice member 8 move (slide) in the Y direction relative to the connecting member 7, the web 7w (the inner surface 7c in the minor diameter direction of the elongated hole 7a) of the connecting member 7 comes into contact with the pipe 27 before the flanges 5f and 7f come into contact with each other. In other words, the pair of flanges 7f of the connecting member 7 face each other so as not to come into contact with the insides of the pair of flanges 5f of the brace segment 5. This prevents the flanges 5f and 7f from coming into contact with each other (preventing damage caused by contact between the flanges).

[0082] Furthermore, after contacting the web 7w of the connecting member 7, the pipe 27 moves (rotates) along the inner surface 7c of the elongated hole 7a. Because the pipe 27 is made of metal, it is possible to suppress buckling of the brace 4 and the friction damper 10 without affecting the important bolt 21 that bears the axial force in order to exert frictional force.

[0083] Furthermore, because the second fastening member 20b is not provided with the pipe 27, as described above, the gap d1' shown in Fig. 6 is larger than the gap d1 shown in Fig. 5. Therefore, even if the web 7w (the inner surface 7c of the elongated hole 7a) and the pipe 27 come into contact with each other in the first fastening member 20a, the web 7w (the inner surface 7c of the elongated hole 7a) and the bolt 21 do not come into contact with each other in the second fastening member 20b (this prevents damage to the bolt 21).

[0084] The multiple fastening members may all be first fastening members 20a (including pipes 27). However, as in the present embodiment, by using only the outer pair of fastening members as first fastening members 20a and the rest as second fastening members 20b (not including pipes 27), the number of pipes required can be reduced, assembly becomes easier, and buckling can be efficiently suppressed.

[0085] <Regarding the Z Direction> In the friction damper 10 of this embodiment, a C-shaped steel connecting member 7 is used as a member for connecting the brace segments (brace segment 5 and brace segment 6) of the brace 4. Because the connecting member 7 (C-shaped steel) has a pair of flanges 7 f, it has a larger cross-sectional area (larger moment of inertia) and is less likely to deform in the Z direction than when a plate-shaped steel plate is used (when only the web 7 w is used). In other words, when an axial force along the X direction (brace spanning direction) acts on the friction damper 10, the pair of flanges 7 f of the connecting member 7 suppresses buckling of the brace 4 and the friction damper 10 in the Z direction. Therefore, in this case as well, buckling can be suppressed without affecting the bolts 21.

[0086] In particular, in this embodiment, a pair of connecting members 7 are provided on both sides of the web 5w of the brace fragment 5 so as to sandwich the web 5w, and a pair of splice members 8 are provided on both sides of the web 7w of the pair of connecting members 7, thereby further suppressing buckling in the Z direction.

[0087] <<Modified Examples of Friction Damper>> In the friction damper 10 of the present embodiment described above, the pipe 27 is a long pipe having a length spanning from the pressing member 8 (third pressure contact plate) on one side in the Z direction to the pressing member 8 (third pressure contact plate) on the other side in the Z direction. However, the pipe may be a short pipe having a length spanning two or more pressure contact plates (hereinafter sometimes simply referred to as "two pressure contact plates") that form at least one of the four sliding surfaces, as in friction dampers 10A of a first modified example to friction dampers 10C of a third modified example described below.

[0088] <First Modification> FIG. 7 is a cross-sectional view of the periphery of a first fastening member 20a in a friction damper 10A of a first modification.

[0089] In the friction damper 10A of the first modified example, the pipe 27A has a length that spans the web 7w (second pressure plate) of the connecting member 7 on one side in the Z direction and the splicing member 8 (third pressure plate) on the other side in the Z direction. Here, FIG. 7 shows an example in which the other side in the Z direction is vertically downward (this also applies to the subsequent modified examples). That is, the pipe 27A is positioned so as to be supported by the washer 23 located vertically downward. However, the pipe 27A may be supported by another member so as to be positioned so as to have a length that spans the splicing member 8 (third pressure plate) on one side (upper) in the Z direction and the web 7w (second pressure plate) of the connecting member 7 on the other side (lower) in the Z direction. In this way, the pipe 27A can be positioned so as to span any two pressure plates.

[0090] <Second Modification> FIG. 8 is a cross-sectional view of the periphery of a first fastening member 20a in a friction damper 10B of a second modification.

[0091] In the friction damper 10B of the second modified example, the pipe 27B has a length that spans the web 5w (first pressure contact plate) of the brace segment 5 and the splice member 8 (third pressure contact plate) on the other side in the Z direction. Here, in FIG. 8 , the pipe 27B is positioned so as to be supported by the washer 23 located vertically below. However, the pipe 27B may be supported by another member and positioned so as to have a length that spans the splice member 8 (third pressure contact plate) on one side (upper) in the Z direction and the web 5w (first pressure contact plate) of the brace segment 5. In this way, the pipe 27B can be positioned so as to span any two pressure contact plates.

[0092] <Third Modification> FIG. 9 is a cross-sectional view of the periphery of a first fastening member 20a in a friction damper 10C of a third modification.

[0093] In the friction damper 10C of the third modified example, the pipe 27C has a length that spans the web 7w (second pressure contact plate) of the connecting member 7 on the other side (lower) in the Z direction and the splicing member 8 (third pressure contact plate) on the other side in the Z direction. Here, in FIG. 9 , the pipe 27C is positioned so as to be supported by the washer 23 located vertically below. However, the pipe 27C may be supported by another member so as to be positioned so as to have a length that spans the splicing member 8 (third pressure contact plate) on one side (upper) in the Z direction and the web 7w (second pressure contact plate) of the connecting member 7 on one side (upper) in the Z direction. In this way, the pipe 27C can be positioned so as to span any two pressure contact plates.

[0094] In the friction damper 10 of the present embodiment described above, the pipe 27 is a long pipe formed integrally across the splice member 8 (third pressure contact plate) on one side in the Z direction and the splice member 8 (third pressure contact plate) on the other side in the Z direction. However, the pipe may be a split pipe formed by splitting the long pipe, as in a friction damper 10D of a fourth modified example described below. <Fourth Modification> Figure 10 is a cross-sectional view of the periphery of the first fastening member 20a in a friction damper 10D of the fourth modified example.

[0095] The friction damper 10D of the fourth modified example has a divided pipe 27D and a pipe 28D (a continuous pipe made by connecting multiple divided pipes). The pipe 27D has a length that spans the web 5w (first pressure contact plate) of the brace segment 5 and the splice member 8 (third pressure contact plate) on the other side in the Z direction. The pipe 28D has a length that spans the splice member 8 (third pressure contact plate) on one side (upper) in the Z direction and the web 5w (first pressure contact plate) of the brace segment 5. This allows the pipe to quickly come into contact with the web 7w (second pressure contact plate) of the connecting member 7.

[0096] Furthermore, in the friction damper 10A of the first modified example to the friction damper 10D of the fourth modified example described above, the pipe is positioned so as to span at least the attachment member 8 (the pipe is housed in the bolt hole 8a). However, this is not limited to these, and the pipe may not be housed in the bolt hole 8a of the attachment member 8, as in the friction damper 10E of the fifth modified example and the friction damper 10F of the sixth modified example described below.

[0097] <Fifth Modification> FIG. 11 is a cross-sectional view of the periphery of a first fastening member 20a in a friction damper 10E according to a fifth modification.

[0098] In the friction damper 10E of the fifth modification, the pipe 27E has a length that spans from the web 7w (second pressure contact plate) of the connecting member 7 on one side in the Z direction to the web 7w (second pressure contact plate) of the connecting member 7 on the other side in the Z direction. The pipe 27E is not received in the bolt hole 8a of the splicing member 8. In this case, the diameter of the bolt hole 8a is formed to be slightly larger than the diameter of the bolt 21 and smaller than the outer diameter of the pipe 27, so that the pipe 27E can be positioned so as to be supported by the splicing member 8 located vertically below. This allows the splicing member 8 located vertically below to be integrated with the washer 23 (i.e., the washer 23 can be omitted, reducing the number of parts).

[0099] <Sixth Modification> FIG. 12 is a cross-sectional view of the periphery of a first fastening member 20a in a friction damper 10F of a sixth modification.

[0100] In the friction damper 10F of the sixth modified example, the pipe 27F has a length that spans the web 5w (first pressure-connected plate) of the brace segment 5 and the web 7w (second pressure-connected plate) of the connecting member 7 on the other side in the Z direction. Here, in FIG. 12 , the pipe 27F is positioned so as to be supported by the splicing member 8 located vertically below. However, the pipe 27F may be supported by another member so as to be positioned at a position that spans the web 7w (second pressure-connected plate) of the connecting member 7 on one side (upper) in the Z direction and the web 5w (first pressure-connected plate) of the brace segment 5. In this way, the pipe 27F can be positioned so as to span any two pressure-connected plates.

[0101] <Seventh Modification> Figure 13 is a cross-sectional view of the periphery of the first fastening member 20a in a friction damper 10G of a seventh modification. The friction damper 10G of the seventh modification has divided pipes 27G and 28G (a continuous pipe formed by connecting multiple divided pipes). The pipe 27G has a length that spans the web 5w (first pressure-contact plate) of the brace segment 5 and the web 7w (second pressure-contact plate) of the connecting member 7 on the other side in the Z direction. The pipe 28G has a length that spans the web 7w (second pressure-contact plate) of the connecting member 7 on one side (upper) in the Z direction and the web 5w (first pressure-contact plate) of the brace segment 5. This allows the pipe to quickly come into contact with the web 7w (second pressure-contact plate) of the connecting member 7.

[0102] ===Other Embodiments===The above embodiments are intended to facilitate understanding of the present invention and are not intended to limit the present invention. The present invention may be modified or improved without departing from the spirit thereof, and it goes without saying that the present invention includes equivalents thereof. In particular, the embodiments described below are also included in the present invention.

[0103] In the above-described embodiment, the friction damper 10 is incorporated into the brace 4 of the beam-column frame 1, but this is not limiting and the friction damper may be incorporated into a part of the building other than the brace (for example, a stud or a partition wall). The friction damper may also be incorporated into a structure other than a building. The friction damper may be installed between a pair of members that move relative to each other due to an external force such as an earthquake.

[0104] In the above-described embodiment, the brace segments 5, 6 and the gusset plates 2 are joined by pin joints using the pin joint structures 3, but this is not limiting and rigid joints may also be used. For example, the brace segments 5, 6 may be joined to the corresponding gusset plates 2 by welding or bolts without using the pin joint structures 3.

[0105] In addition, in the above-described embodiment, the surfaces of the webs 5w, 6w of the brace fragments 5, 6 are aligned along the structural plane of the beam-column structure 1, but this is not limited to this, and the surfaces of the webs 5w, 6w may be perpendicular to the structural plane of the beam-column structure.

[0106] DESCRIPTION OF SYMBOLS 1 Column-beam frame 1a Column 1b Beam 2 Gusset plate 3 Pin joint structure 4 Brace 5 Brace fragment (one member; H-shaped steel) 5a, 5b, 5c Bolt hole 5f Flange 5w Web (first pressure-welded plate) 5m Friction plate 6 Brace fragment (other member; H-shaped steel) 6f Flange 6w Web 7 Connecting member (C-shaped steel) 7a Slotted hole 7b Bolt hole 7c Inner surface 7f Flange 7w Web (second pressure-welded plate) 7s Sliding plate 8 Splice member (flat steel, third pressure-welded plate) 8a, 8b, 8c Bolt hole 8m Friction plate 10, 10A, 10B, 10C, 10D, 10E, 10F, 10G Friction damper 20a First fastening member 20b Second fastening member 21 Bolt 22 Nut 23 Washer 24 Disc spring 25 Guide bush 26 Splice plate 27, 27A, 27B, 27C, 27D, 27E, 27F, 27G, 28D, 28G Pipe 30 Bolt 40 Bolt

Claims

1. A friction damper that is disposed between a pair of members that move relatively in a predetermined direction, and that suppresses the relative movement by frictional force between pressure plates that slide in conjunction with the relative movement, comprising: a first pressure plate that is integral with one of the pair of members; a pair of second pressure plates that are integral with the other of the pair of members and that sandwich the first pressure plate from both sides with a predetermined pressure; a third pressure plate that is integral with one of the members and that sandwiches the second pressure plate on one side of the pair of second pressure plates from the one side with the first pressure plate; and a third pressure plate that is integral with one of the members and that sandwiches the second pressure plate on the other side of the pair of second pressure plates from the other side with the first pressure plate. a first fastening member that is inserted through the through hole of the first crimping plate, the through hole of the pair of second crimping plates, and the through holes of the third crimping plates on the one side and the other side, and presses the first crimping plate, the pair of second crimping plates, and the third crimping plates on the one side and the other side together in a plate thickness direction perpendicular to the opposing surfaces of the first crimping plate and the pair of second crimping plates; the through holes of the pair of second crimping plates are elongated holes; the through holes of the first crimping plate and the through holes of the third crimping plates on the one side and the other side are bolt holes; and the first fastening member has a bolt inserted through the elongated hole and the bolt hole, a nut threaded onto the bolt, and a pipe through which the bolt is inserted and which is accommodated in the elongated hole and the bolt hole; Axial force acts on the friction damper in the predetermined direction, and the pipe, which is in contact with the inner surface of the long hole in the minor diameter direction, suppresses buckling of the sliding surface between the sliding press-welded plates in the in-plane direction.

2. A friction damper according to claim 1, wherein the pipe has a length that spans two or more pressure plates that form at least one of the four sliding surfaces.

3. A friction damper according to claim 1, wherein the pipe is a long pipe having a length spanning from the third pressure contact plate on one side to the third pressure contact plate on the other side.

4. A friction damper according to claim 1, wherein the pipe is a short pipe having a length spanning from the second pressure contact plate on one side to the second pressure contact plate on the other side.

5. A friction damper according to claim 4, wherein the diameter of the through hole of the third pressure plate on the other side is smaller than the outer diameter of the pipe.

6. The friction damper according to claim 1, wherein the pipe is a split pipe.

7. The friction damper according to claim 6, wherein the pipe is a continuous pipe made by connecting a plurality of the segment pipes.

8. A friction damper as described in claim 1, wherein the first pressure plate is a web of an H-shaped steel and the pair of second pressure plates are webs of C-shaped steel, and the pair of flanges of the C-shaped steel face each other so as not to come into contact with the inside of the pair of flanges of the H-shaped steel.

9. A friction damper as described in any one of claims 1 to 8, which has second fastening members that are the first fastening members excluding the pipe, wherein the first fastening members are provided as a pair between the pair of members, and the second fastening member is provided between the pair of first fastening members between the pair of members.

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