JP2000234648A - Friction damper - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a friction damper, having a large freedom degree of design, which can variously change an element or factor generating friction. SOLUTION: A friction damper, for damping a relative motion generated between two structure 2, 3 by friction force, includes a friction generating device 5 set up in one structure 3 and a connection shaft 6 set up in the other structure 2, and the friction generating device 5 comprises a hold frame 9, plurality of sheets of presser plates 15 held by the hold frame 9 to be arranged in laminated, at least a sheet of slide plate 18 arranged slidable between the mutually adjacent presser plates 15, 15 to connect one end part rotatably to the connection shaft 6, and load giving means 28, 29 incorporated in the hold frame 9 to give a load over to an entire retaining plate 15 and the slide plate 18 in a thickness direction thereof.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a friction damper, and more particularly to a friction damper for attenuating a relative movement between two structures caused by an earthquake or the like.

[0002]

2. Description of the Related Art In recent years, many seismic isolation structures have been adopted for buildings in preparation for the occurrence of a large-scale earthquake. This seismic isolation structure generally includes an isolator (seismic isolation bearing) made of laminated rubber and the like that transmits vibration to the building by prolonging the vibration caused by the earthquake between the building and the foundation, and absorbs vibration energy to generate vibration. This is achieved by arranging a damper for attenuating the pressure.

[0003] A damper having a damping function in the isolator itself by embedding a lead plug in the isolator or making the rubber material of the laminated rubber have a high damping property is provided separately from the isolator. A damper made of a lead bar or a steel bar used in combination therewith is known. However, the former has a disadvantage that the degree of freedom in design is small, and the latter has a disadvantage that the price is high.

There is also known an isolator having a damping function by attaching a Teflon plate to the lower surface of an isolator and attaching a stainless steel plate to a base plate on the base side to generate a sliding frictional force between the Teflon plate and the stainless steel plate. Have been. However, in this case, since the load supported by the isolator is a load for generating a frictional force, it is necessary to consider a change in the load. Further, since only one slide surface can be obtained, the obtained damping force is limited.

[0005] As a damper by such friction, a damper incorporating a disc spring is also known. This friction damper is installed separately from the isolator, but since the load applied to the disc spring is obtained from the supporting load, the influence of the load fluctuation is not small. Also, only one sliding surface can be obtained.

Further, a friction damper as disclosed in Japanese Patent Application Laid-Open No. 6-323355 is also known. Since the friction damper compresses the disc spring with the bolt, the load can be adjusted and the load can be kept constant. However, in this friction damper, since the number of disc springs to be installed is limited, the adjustment of the load is also limited. Further, this prior art device cannot take a large amount of displacement and cannot cope with excessive vibration.

[0007]

SUMMARY OF THE INVENTION The present invention has been made on the basis of the above technical background, and has the following objects. SUMMARY OF THE INVENTION An object of the present invention is to provide a large degree of freedom of design and to allow various factors or factors to generate friction, thereby obtaining a large and large damping force with one device, reducing the number of dampers and reducing the overall cost. Another object of the present invention is to provide a friction damper capable of reducing the frictional force.

[0008]

The present invention employs the following means to achieve the above object. That is, the present invention is a friction damper for attenuating relative motion generated between two structures by frictional force,
A friction generating device installed on one of the structures, and a connecting shaft installed on the other of the structures, wherein the friction generating device is held by the holding frame, and is stacked and arranged. A plurality of holding plates, at least one sliding plate slidably arranged between the holding plates adjacent to each other and rotatably connected to the connection shaft at an end, and incorporated in the holding frame. And a load applying means for applying a load in the thickness direction of the pressing plate and the sliding plate over the entirety thereof.

When a relative motion occurs between the two structures due to an earthquake or the like, the sliding plate of the friction generator rotates with respect to the connecting shaft following the motion and slides between the sliding plate and the holding plate. Is generated. The kinetic energy is absorbed and attenuated by the friction generated when the sliding plate slides. The load for generating friction is always constant because the load applying means is incorporated in the holding frame, and the magnitude of the damping force is changed by changing the number of load applying means, the number of sliding plates, and the like. It can be set freely.

[0010] More specifically, the holding frame is rotatably attached to one of the structures. The sliding plate has an end protruding outward from the holding frame, and is rotatably connected to the connection shaft.

The holding frame may comprise a bottom plate, a pair of side plates fixed on the bottom plate at a distance from each other, and an upper plate fixed on the side plate. In this case, the holding plate and the sliding plate are arranged between the bottom plate and the top plate, and the sliding plate has an end protruding outward from between the side plates.

Each side plate is provided with an opening, and the holding plate has a projection fitted into each opening. The bottom plate has a boss at its lower portion for rotatably mounting the holding frame to one of the structures.

The load applying means includes a spring member disposed on the uppermost pressing plate, and a pressing member for pressing the spring member toward the uppermost pressing plate, wherein the pressing member is configured to hold the holding member. It consists of bolts screwed onto the upper plate of the frame. One or a plurality of the friction generating devices may be installed on the outer periphery of the connection shaft at equal angular intervals.

[0014] The holding frame may be constituted by a cylinder having a flange at upper and lower portions and having an opening at a peripheral wall, and in this case, the connecting shaft extends inward of the cylinder. The holding plate and the sliding plate are disposed between the upper and lower flanges, and the sliding plate extends inward of the cylindrical body through the opening, and an end of the sliding plate rotates about the connection shaft. Linked as possible.

Each end of the holding plate is connected to each other by a rod extending through the upper flange toward the lower flange. The load applying means includes a spring member mounted on the rod on the upper flange, and a nut screwed to the rod and pressing the spring member toward the upper flange.

[0016] A plurality of plate groups including the holding plate and the sliding plate are arranged at equal angular intervals between the upper and lower flanges. An annular plate is non-rotatably fitted to the connection shaft, and an end of the sliding plate is rotatably connected to the annular plate.

[0017]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows an application example of a friction damper according to the present invention. A friction damper 1 includes an isolator 4 between a building 2 and a foundation 3 which are two structures.
Is installed adjacent to this.

FIG. 2 is a front view showing the entire friction damper 1. The friction damper 1 includes a friction generator 5 and a connecting shaft 6. The friction generator 5 and the connecting shaft 6 are fixed to the foundation 3 and the building 2, respectively, via base plates 7, 8 having anchor bolts 7a, 8a, respectively.

FIG. 3 is a partially cutaway front view showing details of the friction generator 5 and the connecting shaft 6, and FIGS. 4 and 5 are cross-sectional views taken along lines AA and BB in FIG. 3, respectively. is there. The friction generating device 5 has a holding frame 9. The holding frame 9 includes a bottom plate 10, a pair of side plates 11, 11, and an upper plate 12. The side plates 11, 11 are fixed on the bottom plate 10 by bolts 13, and the upper plate 12 is fixed on the side plates 11, 11 by bolts 14.

In the holding frame 9, a plurality of pressing plates 15 are arranged in a stacked manner. Projections 16 are formed on both sides of the holding plate 15. These projections 16 are provided with openings 17 formed in the side plate.
Is fitted. Thus, the holding plate 15 is held by the holding frame 9 so as not to cause a relative movement with the holding frame 9.

Pressing plates 15, 15 adjacent to each other
Inter and bottom holding plate 15 and bottom plate 10
A sliding plate 18 is slidably disposed between the two. Both ends of these sliding plates 18 protrude and extend outward from the holding frame 9 from between the side plates 11, 11. The frictional force is generated when at least one sliding plate 18 is provided, but the damping force can be easily adjusted by providing a plurality of sliding plates.

A plurality of annular plates 19 are fitted to the connection shaft 6, and a key 20 for preventing the rotation of the annular plate 19 is interposed between the annular plate 19 and the connection shaft 6. A plate 21 for fixing the annular plate 19 to the lower end of the connecting shaft 6 is fixed.

One end of the sliding plate 18 extends between the annular plates 19, 19, and the sliding plate 18 and the annular plate 19 are connected to each other by pins 22 passing therethrough. Thus, the sliding plate 18 is rotatable with respect to the annular plate 19, that is, the connecting shaft 6. Each other end of the sliding plate 18 has a bolt 23 passing therethrough and a nut 24 screwed to the tip thereof.
Are connected to each other. Sliding plate 18,1
A collar 25 for maintaining the interval is attached to the bolt 23 between the eight bolts.

Holding plate 15 and sliding plate 18
Is made of steel plate or the like. In order to improve the slippage and obtain the required frictional force, sliding members 26 and 27 are fixed to the opposing surfaces of the holding plate 15 and the sliding plate 18 and the opposing surfaces of the sliding plate 18 and the bottom plate 10. ing.

Holding plate 15 and bottom plate 10
The sliding material 26 provided on the sliding plate 18 is a plate made of an alloy such as a Teflon plate or a gunmetal, and the sliding material 27 of the sliding plate 18 is a stainless steel plate or the like. The sliding member 26 is fitted and fixed in a concave portion having an appropriate depth provided in each of the plates 10 and 15.

A plurality of disc springs 28 as spring members are arranged on the uppermost holding plate 15. A hexagon socket head bolt 29 is screwed to the upper plate 12 of the holding frame 9 corresponding to each disc spring 28. The hexagon socket head cap screw 29 has a step in the middle, and a guide portion 30 on the tip side of the step passes through the washer 31 and the disc spring 28. Further, the tip of the guide portion 30 is accommodated in a hole 32 provided in the uppermost holding plate 15. The disc spring 28 is pressed by the bolt 29 toward the uppermost holding plate 15 and is compressed. As a result, a load due to the restoring force of the disc spring 28 is applied to the entire holding plate 15 and the sliding plate 18.

A boss 33 having a circular cross section is formed at a lower portion of the bottom plate 10. On the other hand, a fixing plate 35 having a boss hole 36 is
It is fixed by. The boss 33 is fitted in the boss hole 36, whereby the bottom plate 10, that is, the holding frame 9 is rotatable with respect to the foundation 3. The tip of the boss 33 is fixed with a plate 37 for retaining it.

One or a plurality of the above-mentioned friction generating devices 5 can be installed at equal angular intervals on the outer periphery of the connecting shaft 6, and FIGS. 6 and 7 show such an embodiment. FIG.
(A), (b), and (c) show the case where the number of the friction generators 5 is one, two, and three, respectively. FIG. 7 shows a case where four friction generators 5 are provided.

Next, the operation of the friction damper will be described with reference to FIG. When an earthquake occurs and relative movement occurs between the building 2 and the foundation 3 in the direction of the arrow in FIG. 8, the sliding plate 18 of each friction generator 5 rotates with respect to the connection shaft 6 following the movement. At the same time, sliding occurs between the holding plate 15 and the holding plate 15. Further, the holding frame 9 of each friction generating device 5 also rotates about the boss 33 following the movement. The kinetic energy is mainly absorbed and attenuated by the friction generated when the sliding plate 18 slides.

At this time, in the friction generator 5 in which the angle between the movement direction and the extending direction of the sliding plate 18 is small, the rotation angle of the holding frame 9 is small and the displacement of the sliding plate 18 is large. Conversely, in the friction generator 5 in which the angle between the movement direction and the extending direction of the slide plate 18 is large, the rotation angle of the holding frame 9 is large and the displacement of the slide plate 18 is small. That is, if the number of the friction generating devices 5 is large, even if the motion occurs in any direction, any of the friction generating devices greatly contributes to the damping action, and the motion can be reliably attenuated. The magnitude of the damping force can be freely set by changing the number of the friction generators 5 installed.

The magnitude of the damping force due to the friction of each of the friction generating devices 5 can be freely changed by changing the number, size, or number of the disc springs 28, since the frictional force is substantially proportional to the load. be able to. Since the load applied to each friction surface does not change even if the friction surfaces are increased,
The friction force will be proportional to the number of friction surfaces. Therefore, by increasing the number of sliding plates 18, the friction surface increases, and the damping force due to friction can be increased.

Further, by using a Teflon plate or an alloy plate for the sliding members 26 and 27, the friction becomes Coulomb friction, so that the resistance before sliding starts is large, and it is possible to prevent shaking due to a wind or a small earthquake. . That is, it can be said that the above-described friction damper has a trigger function.

Further, according to the above-mentioned friction damper, since the frictional force is controlled by the force of the disc spring 28 incorporated in the holding frame 9, the load applied to the slide plate 18 does not fluctuate, and the damping force is stabilized. Even if a residual displacement occurs in the isolator 4 due to a large displacement at the time of a large earthquake, since the frictional force is released by loosening the bolt 29 pressing the disc spring 28, the release of the residual displacement is easy. Also, by changing the length of the sliding plate 18, the amount of movement can be changed.

When a plurality of friction generators 5 are installed, FIG.
As shown in FIG. 9, a base plate 7 may be provided for each friction generator, but as shown in FIG. 9, one base plate 7 is provided, and a plurality of friction generators 5 are provided thereon. Is also good.

10 to 12 show another embodiment of the present invention. FIG. 10 is a front view, FIG. 11 is a horizontal sectional view,
FIG. 12 is a sectional view taken along the line CC of FIG. In this embodiment, the holding frame 9 has upper and lower flanges 4.
It consists of a cylinder 42 with 0,41. Connecting shaft 6
Has the same structure as that of the above-described embodiment, but is arranged so as to extend inward of the cylindrical body 42. Holding frame 9
Are anchor bolts 43 provided on the lower flange 41.
And is fixed to the foundation 3 via the

Holding plate 15 and sliding plate 18
Is disposed between the upper and lower flanges 40 and 41. An opening 44 is formed in the peripheral wall of the cylindrical body 42. One end of the sliding plate 18 extends inward of the cylindrical body 42 through the opening 44 and is rotatably connected to the annular plate 19 provided on the connecting shaft 6.

A plurality of plate groups 45 each including the press plate 15 and the slide plate 18 are arranged at equal angular intervals on the outer periphery of the cylindrical body 42. As the sliding members 26 and 27 provided on the holding plate 15 and the sliding plate 18, those similar to those described in the above embodiment can be used.

Both ends of each holding plate 18 are connected to each other by a pair of rods 46, 46 penetrating through the upper flange 40 and extending toward the lower flange 41.
The lower ends of these rods 46, 46 are
Is accommodated in a positioning hole 47 provided in the main body. A disc spring 28 is attached to a portion of the rods 46, 46 protruding from the upper flange 40. The disc spring 28 is fixed to an upper flange 40 by a nut 48 screwed to a rod 46.
And is compressed. Thereby, over the entire holding plate 15 and the sliding plate 18,
A load is applied.

The state when the damper according to this embodiment is operated is shown by a chain line in FIG. According to this embodiment, since the holding frame 9 is fixed to the foundation 3, rotation occurs between the holding plate 15 and the sliding plate 18 during operation. Therefore, even if the angle between the vibration direction and the extending direction of the sliding plate 18 is large, friction due to rotational sliding occurs. In addition, this embodiment also provides the same advantages as those described in the above embodiment.

In the above description, the case where the friction damper according to the present invention is applied to a seismic isolation system of a building has been described as an example. However, the present invention is applicable to any other structure between two structures where relative motion due to vibration occurs. It can also be applied to other systems.

[0041]

As described above, according to the present invention, the degree of freedom in design is large, and it is possible to change various factors or factors that cause friction, and therefore a large damping force can be obtained with one device. In addition, the number of dampers can be reduced to reduce the overall price.

[Brief description of the drawings]

FIG. 1 is a diagram showing an application example of a friction damper according to the present invention.

FIG. 2 is a front view showing the entire friction damper.

FIG. 3 is a partially broken front view showing details of a friction generating device and a connection shaft.

FIG. 4 is a cross-sectional view taken along line AA of FIG. 3;

FIG. 5 is a sectional view taken along the line BB in FIG. 3;

FIG. 6 is a diagram illustrating an installation mode of a friction generator.

FIG. 7 is a diagram showing an installation mode of a friction generator.

FIG. 8 is a diagram for explaining the operation.

FIG. 9 is a diagram showing another aspect of the base plate when a plurality of friction generating devices are installed.

FIG. 10 is a front view showing another embodiment.

FIG. 11 is a horizontal sectional view showing the same embodiment.

FIG. 12 is a sectional view taken along the line BB of FIG. 11;

[Explanation of symbols]

 1: friction damper 2: building 3: foundation 4: isolator 5: friction generator 6: connecting shaft 7: base plate 9: holding frame 10: bottom plate 11: side plate 12: top plate 15: holding plate 16: protrusion 17: Opening 18: Sliding plate 19: Annular plate 26: Sliding material 27: Sliding material 28: Belleville spring 29: Hexagon socket head bolt 33: Boss 35: Fixed plate 36: Boss hole 40: Upper flange 41: Lower flange 42 : Cylindrical body 44: Opening 45: Plate group 46: Rod 47: Positioning hole 48: Nut

Claims (14)

[Claims] 1. A friction damper for attenuating a relative movement generated between two structures by a frictional force, wherein the friction damper is installed on one of the structures and the friction damper is installed on the other of the structures. Wherein the friction generating device comprises: a holding frame; a plurality of holding plates held by the holding frame and arranged in a stack; and slidably arranged between the holding plates adjacent to each other. At least one sliding plate whose end is rotatably connected to the connecting shaft; and a load that is incorporated in the holding frame and that extends in the thickness direction of the pressing plate and the sliding plate over the entirety thereof. And a load applying means for applying a force. 2. The friction damper according to claim 1, wherein said holding frame is rotatably attached to one of said structures. 3. A friction damper according to claim 1, wherein said sliding plate has an end protruding outward from said holding frame and rotatably connected to said connecting shaft. 4. The holding frame according to claim 1, wherein said holding frame is fixed to said bottom plate at a distance from each other.
A pair of side plates, and an upper plate fixed on the side plates, wherein the holding plate and the sliding plate are disposed between the bottom plate and the upper plate, and the sliding plate has an end thereof. 2. The device according to claim 1, wherein a portion extends outwardly from between the side plates.
Or the friction damper according to 2. 5. The friction damper according to claim 4, wherein each side plate is provided with an opening, and said holding plate has a projection fitted into each opening. 6. A bottom plate having a boss at a lower portion thereof for rotatably attaching the holding frame to one of the structures.
The described friction damper. 7. The load applying means includes a spring member disposed on the uppermost pressing plate, and a pressing member for pressing the spring member toward the uppermost pressing plate. A friction damper according to any one of claims 1 to 6. 8. The friction damper according to claim 4, wherein said pressing member is a bolt screwed to said upper plate of said holding frame. 9. The friction damper according to claim 1, wherein a plurality of said friction generating devices are installed at equal angular intervals around an outer periphery of said connecting shaft. 10. The holding frame comprises a cylindrical body having a flange at upper and lower portions and having an opening at a peripheral wall, wherein the connecting shaft is installed so as to extend inward of the cylindrical body. A holding plate and the sliding plate are disposed between the upper and lower flanges, and the sliding plate extends inward of the cylindrical body through the opening, and an end of the sliding plate is rotatably connected to the connection shaft. The friction damper according to claim 1, wherein: 11. A friction damper according to claim 10, wherein each end of said holding plate is connected to each other by a rod extending through said upper flange toward said lower flange. 12. The load applying means includes: a spring member mounted on the rod on the upper flange; and a nut screwed to the rod and pressing the spring member toward the upper flange. The friction damper according to claim 11, characterized in that: 13. The friction according to claim 10, 11 or 12, wherein a plurality of plate groups comprising said holding plate and said sliding plate are arranged at equal angular intervals between said upper and lower flanges. Damper. 14. An annular plate is non-rotatably fitted to said connecting shaft, and an end of said sliding plate is rotatably connected to said annular plate. 2. The friction damper according to 1.