Friction damper

Abstract

To provide a friction damper in which a decrease in frictional force due to frictional heat is less likely to occur.SOLUTION: A friction damper comprises: a pressure-welding plate laminate in which a plurality of pressure-welding plates are laminated and slide against each other to generate a frictional force between the plurality of pressure-welding plates; a bolt that passes through the pressure-welding plate laminate; a nut that screws into the bolt on the opposite side of a head of the bolt; a first washer arranged between the pressure-welding laminate and one of the head or the nut; a first disc spring set arranged between the pressure-welding laminate and the first washer; a second washer arranged between the pressure-welding plate laminate and the other of the head or the nut; and a second disc spring set arranged between the pressure-welding plate laminate and the second washer. The friction damper adjusts the frictional force by a spring load bearing force of the first disc spring set. The second washer comprises a flange that is in contact with the other of the head or the nut, and a guide ring that is in contact with the pressure-welding plate laminate. The second disc spring set and the guide ring press against the pressure-welding plate laminate.SELECTED DRAWING: Figure 2

Description

Technical Field

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

Background Art

[0002] Conventionally, for example, as disclosed in Patent Document 1, there is known a friction damper that consumes vibration energy caused by an earthquake or wind and suppresses relative movement by the frictional force (frictional resistance) between pressure contact plates that move relative to each other in a predetermined direction and slide with the relative movement. In this friction damper, bolts are passed through the pressure contact plates that move relative to each other, a disc spring is provided on the bolt head side, and a nut is screwed onto the bolt to press the pressure contact plates against each other by the spring load bearing force of the disc spring. At this time, a washer is interposed on the nut side so that the spring load bearing force of the disc spring acts on a wider area of the pressure contact plates.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In a friction damper such as that of Patent Document 1, the force applied from the nut side to press the pressure contact plates against each other easily acts on a narrow area near the nut, so high frictional heat is likely to be generated due to the concentrated load. Further, even if a washer is interposed on the nut side, although the inner peripheral side of the washer pressed by the nut transmits the spring load bearing force, the outer peripheral side of the washer pressed by the nut warps in a direction away from the pressure contact plate, making it difficult to transmit the spring load bearing force. For this reason, the area where the spring load bearing force is transmitted becomes a narrow area where the nut is in contact with the pressure contact plate, and the surface pressure increases due to the load acting on the narrow area, resulting in a problem that it is difficult to obtain a desired frictional force because high frictional heat is generated. An object of the present invention is to provide a friction damper in which a decrease in frictional force due to frictional heat is less likely to occur.

Means for Solving the Problems

[0005] To achieve such an object, the present invention provides a pressure plate laminate in which a plurality of pressure plates are stacked and slid relative to each other to generate a frictional force between the plurality of pressure plates, a bolt passing through the pressure plate laminate, a nut screwed with the bolt on the side opposite to the head of the bolt, a first washer disposed between the pressure plate laminate and one of the head or the nut, a first disc spring set disposed between the pressure plate laminate and the first washer, a second washer disposed between the pressure plate laminate and the other of the head or the nut, a second disc spring set disposed between the pressure plate laminate and the second washer, and is provided with a friction damper that adjusts the frictional force by the spring load bearing capacity of the first disc spring set, the second washer includes a flange that abuts against the other of the head or the nut, and a guide ring that abuts against the pressure plate laminate, A friction damper characterized in that the pressure plate laminate is pressed by the second disc spring set and the guide ring. Other features of the present invention will be clarified by the description in this specification.

Effects of the Invention

[0006] According to the present invention, it is possible to provide a friction damper in which a decrease in frictional force due to frictional heat is less likely to occur.

Brief Description of the Drawings

[0007]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Embodiments for Carrying Out the Invention

[0008] At least the following matters become clear from the description in this specification and the attached drawings. (Aspect 1) A pressure contact plate laminate in which a plurality of pressure contact plates are overlapped and slide on each other to generate a frictional force between the plurality of pressure contact plates, A bolt passing through the pressure contact plate laminate, A nut screwed with the bolt on the opposite side of the head of the bolt, A first washer disposed between the pressure contact plate laminate and one of the head or the nut, A first disc spring set disposed between the pressure contact plate laminate and the first washer, A second washer disposed between the pressure contact plate laminate and the other of the head or the nut, A second disc spring set disposed between the pressure contact plate laminate and the second washer, Comprising A friction damper that adjusts the frictional force by the spring load bearing capacity of the first disc spring set, The second washer includes a flange that abuts against the other of the head or the nut, And a guide ring that abuts against the pressure contact plate laminate, A friction damper characterized in that the pressure contact plate laminate is pressed by the second disc spring set and the guide ring.

[0009] Even if the dish spring is deformed so as to be substantially flat when pressed, the outer peripheral portion does not deform so as to lift up and warp like a washer. Therefore, when a second dish spring set is disposed between the pressure contact plate laminate and the second washer as in the friction damper of Embodiment 1, it is possible to press the pressure contact plate laminate at the outer peripheral edge of the second dish spring set. Further, in the friction damper of Embodiment 1, the second washer presses the second dish spring set against the pressure contact plate laminate, and the guide ring also presses the pressure contact plate laminate. Therefore, it is possible to press the pressure contact plate laminate with the outer peripheral edge of the second dish spring set and the guide ring located inside the second dish spring set. For this reason, since the spring load bearing force of the first dish spring set is transmitted to the pressure contact plate laminate in a wider area, the spring load bearing force is dispersed and suppressed from concentrating locally, so that the generation of frictional heat is suppressed and it is possible to provide a friction damper in which a decrease in frictional force due to frictional heat is less likely to occur.

[0010] (Embodiment 2) The friction damper according to Embodiment 1, wherein a contact region of the first dish spring set with the pressure contact plate laminate is an outer peripheral edge of the first dish spring set.

[0011] According to the friction damper of Embodiment 2, the contact region of the first dish spring set with the pressure contact plate laminate is the outer peripheral edge of the first dish spring set, that is, the outer peripheral edge of the dish spring is where the first dish spring set is in contact with the pressure contact plate laminate. Therefore, the first dish spring set is not deformed so that the entire surface is in contact with the pressure contact plate laminate. For this reason, the spring load bearing force of the first dish spring set can be made to act on the outer peripheral edge portion of the first dish spring set, that is, at a position farther from the axis of the bolt, so that the spring load bearing force can act in a wider range.

[0012] (Embodiment 3) The friction damper according to Embodiment 1, wherein a contact region of the second dish spring set with the pressure contact plate laminate extends from an outer peripheral edge to an inner peripheral edge of the second dish spring set.

[0013] According to the friction damper of Mode 3, since the contact area with the pressure contact plate laminate of the second disc spring set extends from the outer peripheral edge to the inner peripheral edge of the second disc spring set, the contact area with the pressure contact plate laminate of the second disc spring set can be surely made larger than the case where only the outer peripheral edge is in contact. For this reason, it becomes possible to disperse and act the spring load bearing capacity.

[0014] (Mode 4) The friction damper according to Mode 1, wherein the first disc spring set is a laminate of a predetermined number of disc springs, and the second disc spring set is a laminate of the disc springs having a number less than the predetermined number.

[0015] According to the friction damper of Mode 4, since the second disc spring set is a laminate of a number of disc springs less than the number of the first disc spring set, when the nut is tightened, the second disc spring set starts to deform more greatly than the first disc spring set. For this reason, since the second disc spring set deforms and the contact area with the pressure contact plate laminate spreads wider than that of the first disc spring set, it becomes possible to make the contact area between the second disc spring set and the pressure contact plate laminate wider than the contact area between the first disc spring set and the pressure contact plate laminate.

[0016] (Mode 5) The friction damper according to any one of Mode 4, wherein the second disc spring set is a laminate of a plurality of the disc springs.

[0017] According to the friction damper of Mode 5, since the second disc spring set is a laminate of a plurality of disc springs, it becomes possible to improve the transmission efficiency of the spring load bearing capacity as compared with the case where there is one disc spring.

[0018] <<<This Embodiment>>> Hereinafter, a friction damper according to an embodiment of the present invention will be described with reference to the drawings. As shown in FIG. 1, for example, the friction damper 10 is incorporated into the brace 1a of the H-shaped steel of the column-beam structure 1. The brace 1a has brace segments 2 and 3 that are divided at appropriate positions in the spanning direction with a predetermined interval therebetween, and the friction damper 10 is incorporated into the divided portion. The friction damper 10 suppresses the relative movement of the brace segments 2 and 3 in the spanning direction when an external force such as an earthquake occurs.

[0019] As shown in FIGS. 2 and 3, the friction damper 10 includes a first pressure plate 11 bolted to the web 2a of one brace segment 2, a second pressure plate 12 that directly uses the web 3a of the other brace segment 3, a high-strength bolt 20 passing through the first pressure plate 11 and the second pressure plate 12, a nut 21 screwed onto the high-strength bolt 20, a first washer 22 and a first disc spring set 23 disposed on the nut 21 side, and a second washer 24 and a second disc spring set 25 disposed on the head 20a side of the high-strength bolt 20.

[0020] A first through hole 11a is formed through the first pressure plate 11 in the plate thickness direction, and a second through hole 12a is formed through the second pressure plate 12 in the plate thickness direction. The first through hole 11a is a circular shape slightly larger than the diameter of the shaft portion 20b of the high-strength bolt 20, and the second through hole 12a is a long hole having a width wider than the inner diameter of the first through hole 11a and extending in the spanning direction. The first pressure plate 11 and the second pressure plate 12 are overlapped in the plate thickness direction, and the high-strength bolt 20 is inserted through the through holes 11a and 12a in a skewering manner, and the nut 21 is screwed onto the tip of the high-strength bolt 20.

[0021] A first washer 22 and a first disc spring set 23 through which the high-strength bolt 20 is inserted are provided between the first pressure plate 11 and the nut 21. The first washer 22 is located on the nut 21 side, and the first disc spring set 23 is located between the first washer 22 and the first pressure plate 11. The first disc spring set 23 is composed of six disc springs 26 stacked in parallel. The inner peripheral edge portion 26a side is disposed on the first washer 22 side, the outer peripheral edge portion 26b side is disposed on the first pressure plate 11 side, and the outer peripheral edge portion 26b is in contact with the first pressure plate 11.

[0022] Also, between the second pressure contact plate 12 and the head (hereinafter simply referred to as the head) 20a of the high-strength bolt 20, a second washer 24 through which the high-strength bolt 20 is inserted and a second disc spring set 25 are provided. The second washer 24 is located on the head 20a side, and the second disc spring set 25 is located between the second washer 24 and the second pressure contact plate 12. The second disc spring set 25 is composed of two disc springs 26 stacked in parallel, and is arranged such that the inner peripheral edge portion 26a side faces the second washer 24 side and the outer peripheral edge portion 26b side faces the second pressure contact plate 12 side.

[0023] The second washer 24 has a small annular portion 24a and a large annular portion 24b with different outer diameters connected in the thickness direction to form an integral body, and has a through hole 24c in the center with an inner diameter slightly larger than the diameter of the shaft portion 20b of the high-strength bolt 20. The outer diameter of the small annular portion 24a is slightly smaller than the inner diameter of the disc spring 26, and the outer diameter of the large annular portion 24b is formed larger than the inner diameter of the disc spring 26.

[0024] The second washer 24 is arranged such that the small annular portion 24a is disposed inside the inner peripheral edge portion 25a of the second disc spring set 25, and the large annular portion 24b is located between the head 20a and the second disc spring set 25. Here, the small annular portion 24a corresponds to a guide ring that contacts the pressure contact plate laminate, and the portion of the large annular portion 24b that protrudes outward from the small annular portion 24a corresponds to a flange. The protruding amount of the small annular portion 24a from the large annular portion 24b is formed larger than the thickness obtained by stacking the plate thickness of the disc spring 26 by the number of sheets (here, two sheets) that the second disc spring set 25 has.

[0025] When the nut 21 is tightened, a pressing force acts between the first pressure contact plate 11 and the second pressure contact plate 12 due to the spring load-bearing capacity of the first disc spring set 23. Then, with the pressing force acting between the first pressure contact plate 11 and the second pressure contact plate 12, the first pressure contact plate 11 and the second pressure contact plate 12 are relatively movable while sliding against each other, and a frictional force corresponding to the pressing force is generated during sliding. This frictional force becomes the damping force of the vibration of the column-beam structure 1. Here, the stacked first pressure contact plate 11 and second pressure contact plate 12 correspond to the pressure contact plate laminate 4 in which a plurality of pressure contact plates are stacked and slide against each other to generate a frictional force between the plurality of pressure contact plates.

[0026] When disc springs are stacked in the same direction, the load strength becomes higher compared to the characteristics of a single disc spring. Therefore, the friction damper 10 can adjust the frictional force by changing the number of disc springs 26 that make up the first disc spring set 23 and by changing the amount of change in the free height of the first disc spring set 23 when the nut 21 is tightened, thereby changing the spring load-bearing capacity of the first disc spring set 23.

[0027] Also, the first disc spring set 23 and the second disc spring set 25, whose spring load-bearing capacities change due to the tightening of the nut 21 screwed onto the single high-strength bolt 20, each use the same disc spring 26 and have different numbers of stacked layers. For this reason, when the nut 21 is tightened, the second disc spring set 25, which has a smaller number of stacked layers than the first disc spring set 23, changes in height more greatly than the first disc spring set 23.

[0028] Then, when the nut 21 is tightened, the height of the second disc spring set 25 decreases and deforms, and as shown in Fig. 4(a), the guide ring 24a of the second washer 24 abuts against the second pressure contact plate 12.

[0029] At this time, in the second pressure contact plate 12, the portion where the guide ring 24a abuts inside the second disc spring set 25 is pressed by the guide ring 24a, and the portion facing the outer peripheral edge portion 26b of the second disc spring set 25 is pressed by the outer peripheral edge portion 26b. Therefore, for example, when a flat washer is provided between the second pressure contact plate and the nut, the outer peripheral edge portion of the flat washer does not warp in a direction away from the second pressure contact plate, and the second pressure contact plate is not pressed only on the inner peripheral edge portion side of the flat washer against which the nut abuts.

[0030] Therefore, by pressing the second pressure contact plate 12 with the guide ring 24a and the second disc spring set 25, a wider area of the second pressure contact plate 12 can be pressed. Therefore, since the pressing force does not concentrate in a narrow range, it is possible to suppress the frictional heat generated between the first pressure contact plate 11 and the second pressure contact plate 12 and prevent a decrease in the frictional force due to the generation of high frictional heat.

[0031] Also, when the nut 21 is further tightened and, as shown in FIG. 4(b), the disc springs 26 of the second disc spring set 25 are overlapped and flexurally deformed so as to approach the second pressure contact plate 12 from the outer peripheral edge portion 26b side of the disc spring 26, the contact region R where the disc springs 26 of the second disc spring set 25 abut against the second pressure contact plate 12 from the outer peripheral edge portion 26b side expands from the outer peripheral edge portion 26b side toward the inner peripheral edge portion 26a side.

[0032] In this way, when the nut 21 is tightened and the contact region R of the disc spring 26 expands, the second pressure contact plate 12 is pressed by the portion where the guide ring 24a abuts inside the second disc spring set 25 and the contact region R that abuts against the second pressure contact plate 12 on the outer peripheral edge portion 26b side of the second disc spring set 25. Therefore, since the pressing force can be dispersed and applied over a wider area, it is possible to suppress the frictional heat generated between the first pressure contact plate 11 and the second pressure contact plate 12 and prevent a decrease in the frictional force due to the generation of high frictional heat.

[0033] In the above-described embodiment, an example in which the pressure contact plate laminate 4 is composed of the first pressure contact plate 11 and the second pressure contact plate 12 has been described. However, the present invention is not limited to this, and the pressure contact plate laminate 4 may be composed of three or more pressure contact plates stacked on one another. For example, as shown in FIG. 5, the pressure contact plate laminate may be composed of three pressure contact plates.

[0034] In this case, the friction damper 10 includes a first pressure contact plate 11 and a third pressure contact plate 13 bolted to the web 2a of one brace fragment 2, a second pressure contact plate 12 in which the web 3a of the other brace fragment 3 is directly reused, a high-strength bolt 20 passing through a pressure contact plate laminate 5 formed by overlapping the first pressure contact plate 11, the second pressure contact plate 12, and the third pressure contact plate 13, a nut 21 screwed onto the high-strength bolt 20, a first washer 22 and a first disc spring set 23 disposed on the nut 21 side, and a second washer 24 and a second disc spring set 25 disposed on the head 20a side. In this case, the nut 21 is tightened, and the guide ring 24a of the second washer 24 and the outer peripheral edge portion 26b side of the disc spring 26 of the second disc spring set 25 abut against the third pressure contact plate 13.

[0035] Also, as shown in FIG. 6, the pressure contact plate laminate may be composed of five pressure contact plates. In this case, the friction damper 10 includes a first pressure contact plate 11 and a third pressure contact plate 13 bolted to the web 2a of one brace fragment 2, a second pressure contact plate 12 in which the web 3a of the other brace fragment 3 is directly reused, a fourth pressure contact plate 14 and a fifth pressure contact plate 15 bolted to both surfaces of the web 3a via filler plates 6, a high-strength bolt 20 passing through a pressure contact plate laminate 7 formed by overlapping the first to fifth pressure contact plates 11, 12, 13, 14, and 15, a nut 21 screwed onto the high-strength bolt 20, a first washer 22 and a first disc spring set 23 disposed on the nut 21 side, and a second washer 24 and a second disc spring set 25 disposed on the head 20a side. In this case, the nut 21 is tightened, and the guide ring 24a of the second washer 24 and the outer peripheral edge portion 26b side of the disc spring 26 of the second disc spring set 25 abut against the fifth pressure contact plate 15.

[0036] In the above embodiment, an example was described in which the first disc spring set 23 is composed of six disc springs 26, and the second disc spring set 25 is composed of two of the same disc springs 26 as the first disc spring set 23. However, the present invention is not limited to this. The number of disc springs 26 constituting each of the disc spring sets 23 and 25 may be such that the number of disc springs 26 constituting the first disc spring set 23 is larger than the number of disc springs 26 constituting the second disc spring set 25. Also, the number of disc springs 26 constituting the second disc spring set 25 may be one.

[0037] Also, in the above embodiment, an example was described in which the first disc spring set 23 and the second disc spring set 25 are configured using the same disc springs 26. However, the present invention is not limited to this, and a configuration in which the disc springs of the first disc spring set 23 and the disc springs of the second disc spring set 25 are different may be adopted. In this case, the amount of deflection deformation with respect to the load in the second disc spring set 25 is set to be larger than the amount of deflection deformation with respect to the load in the first disc spring set 23.

[0038] Also, in the above embodiment, an example was described in which the first disc spring set 23 is arranged on the nut 21 side and the second disc spring set 25 is arranged on the head 20a side. However, the present invention is not limited to this, and the first disc spring set 23 may be arranged on the head 20a side and the second disc spring set 25 may be arranged on the nut 21 side. ===Other Embodiments===

[0039] As described above, embodiments of the present invention have been described. However, the above embodiments are for facilitating the understanding of the present invention and are not for limiting the interpretation of the present invention. Also, the present invention can be changed and improved without departing from its gist, and it goes without saying that equivalents of the present invention are included therein.

Explanation of Reference Numerals

[0040] 1 Column-beam structure, 1a Brace, 2 Brace fragment, 2a Web, 3 Brace fragment, 3a Web, 4 Pressure-bonded plate laminate, 5 Pressure-bonded plate laminate, 6 filler plate, 7 pressure contact plate laminate, 10 friction damper, 11 first pressure contact plate, 11a first through hole, 12 second pressure contact plate, 12a second through hole, 13 third pressure contact plate, 14 fourth pressure contact plate, 15 fifth pressure contact plate, 20 high-strength bolt, 20a head, 20b shaft portion, 21 nut, 22 first washer, 23 first disc spring set, 24 second washer, 24a small annular portion, 24b large annular portion, 24c through hole, 25 second disc spring set, 26a inner peripheral edge portion, 26b outer peripheral edge portion, R contact region

Claims

1. A friction damper comprising a laminated body of pressure plates that are stacked on top of each other and slide relative to each other to generate frictional force between the plurality of pressure plates, a bolt passing through the laminated body of pressure plates, a nut screwed onto the bolt on the side opposite to the head of the bolt, a first washer disposed between the laminated body of pressure plates and one of the head or the nut, a first disc spring set disposed between the laminated body of pressure plates and the first washer, a second washer disposed between the laminated body of pressure plates and the other of the head or the nut, a second disc spring set disposed between the laminated body of pressure plates and the second washer, characterized in that: it is a friction damper that adjusts the frictional force by the spring load bearing capacity of the first disc spring set, the second washer includes a flange that abuts against the other of the head or the nut, and a guide ring that abuts against the laminated body of pressure plates, and the pressure plate laminated body is pressed by the second disc spring set and the guide ring.

2. The friction damper according to claim 1, wherein the contact region of the first disc spring set with the laminated body of pressure plates is the outer peripheral edge of the first disc spring set.

3. The friction damper according to claim 1, wherein the contact region of the second disc spring set with the second washer extends from the outer peripheral edge to the inner peripheral edge of the second disc spring set.

4. The friction damper according to claim 1, wherein the first disc spring set is a stack of a predetermined number of disc springs, and the second disc spring set has a number of disc springs less than the predetermined number.

5. The friction damper according to claim 4, wherein the second disc spring set is a stack of a plurality of the disc springs.

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