JPH03272343A - Dual type mass damper - Google Patents

Abstract

PURPOSE:To provide effective damping against both of large and small vibration by mounting masses of a mass damper for small vibration, through a laminated rubber, on the mass of a mass damper for large vibration which is supported on a floor surface through a bearing and in which the dampers and springs are respectively interposed between itself and rigid bodies on its four peripheral sides. CONSTITUTION:When a floor 3 vibrates slightly, a first mass on a mass damper 1 for large vibration does not work because it is supported by bearings 4 and friction works a little. On the other hand, a second mass 9 cannot be deformed greatly as it is supported by the first mass 2 through a laminated rubber 10, but it works as a mass damper because it can move with small vibration without any friction and rattling. Additionally, when the floor 3 vibrates greatly, the first mass 2 moves following great deformation as it is mounted on the floor 3 through the bearings 4, the first mass 2 and the second mass 9 simultaneously move and both mass dampers 1, 8 work as a piece of mass damper integrated in one body.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a dual mass damper for reducing horizontal vibrations of buildings and other structures.

(Prior art) Fig. 5 shows an example of a conventional mass damper for small vibrations, in which both ends of a leaf spring (bl) are bent to which a damping material (a) is attached, and the free end is fixed to the floor (0). A mass (weight) (d) is attached to the center of the plate spring.

Figure 6 shows an example of a conventional mass damper for large vibrations, and shows the Y-direction rail (BY) installed on the Heath prisoner.
, lower mass frame (P) to roller bearing (CY)
) is mounted movably in the Y direction, and the lower mass frame (
χ direction rail (BX) on P), roller bearing (
An upper mass frame (Q) is mounted on the heath A and the lower mass frame (P) so as to be movable in the X direction, and a Y direction damper (DY) and an X direction damper (
DX), and a Y-direction buffer spring (EV) and a A buffer spring (EX) is interposed, and the damper and spring are configured to reduce vibrations of the structure due to wind.

In the figure, (FY) and (FX) are a Y-direction oil shock absorber and an X-direction oil shock absorber, respectively.

(Problem B to be solved by the invention) However, in the former case, since a temporary spring is used, large deformations cannot be followed.

The latter is configured so that the mass moves on the rail via bearings, but it is impossible to completely eliminate friction, so even small vibrations will not move the mass damper.

The present invention has been developed in view of the problems of the prior art described above! The purpose of this is to provide a mass damper that is effective against both small and large vibrations.

(Means for Solving the Problem) In order to achieve the above-mentioned object, the double mass damper according to the present invention is provided with a double mass damper that is supported via floor bearings, and that is mounted on the same floor and on the floor. On the mass damper mass for large vibration [J], in which a damper and a spring are respectively interposed between the surrounding rigid body, there is a mass damper mass for small vibration with adjusted natural period and damping.
It is constructed by mounting the mass of the damper with laminated rubber interposed therebetween.

(Function) Since the present invention is configured as described above, when the floor vibrates small, the mass of the mass damper for large vibrations is supported by the floor surface via bearings and a little friction acts.
It doesn't move.

On the other hand, the mass of the mass damper for small vibrations is supported by the mass of the mass damper for large vibrations via laminated rubber, so it moves and functions as a mass damper.

When the floor vibrates greatly, the masses of the mass damper for large vibrations and the mass damper for small vibrations move together and work as one mass damper. At this time, the mass of the mass damper for large vibrations is attached to the floor surface. Because it is mounted via bearings, it can follow large deformations.

(Example) The present invention will be described below with reference to the illustrated embodiments.

(1) is a mass damper for large vibrations;
Square (2) (hereinafter referred to as the first square) is on the floor (
3) via a bearing (4).

4 of the same square (2) on the first square (2) and the floor (3)
It is assumed that a spring (6) (hereinafter referred to as the first spring) is interposed between the W11 body such as a wall (5) erected around the periphery, and the natural period in the χY force direction is different. Thus, the number of first springs (6) is changed in each of the X and Y directions. Furthermore, in order to reduce the vibration of the first mass (2), a damper (
7) is provided, and the natural period and damping of the first mass are adjusted by the damper (7) and the first spring (6).

(8) i;! In the mass damper for small vibrations 11], the mass (9) (hereinafter referred to as the second mass) in the mass damper (8) is stacked on the first mass (2) in the mass damper (1) for large vibrations. It is supported via rubber (10), and horizontal rigidity is provided by the laminated rubber (10).

A spring (11) (hereinafter referred to as a second spring) is interposed between the second mass (9) and the first mass (2). The same spring (work 1) is designed based on the assumption that the natural periods in the x and Y force directions are different.
11) is changed in each of the X and Y directions. Note that a damper (12) is disposed between the second mass (9) and the first mass (2) so as to reduce the vibration of the second mass (9), and the damper (]]) and the second spring (11), the natural period and attenuation of the second mass (9) are adjusted.

Since the illustrated embodiment is constructed as described above, when the floor (3) vibrates small, the large vibration mass damper (1)
) is supported by a bearing (4) on the floor (3) and does not move due to a small amount of friction.

On the other hand, the second mass (9) in the mass damper for small vibrations (8) has a laminated rubber (10
), so it cannot undergo large deformations, but it can move with small vibrations without friction or rattling, so it can move when the floor (3) vibrates small as mentioned above. Works as a mass damper.

Furthermore, when the floor (3) vibrates greatly, the first mass (2) moves following the large deformation, since it is mounted on the floor (3) via a bearing (4). square (2
) and the second mass (8) move together, and both the mass dampers (1) and (8) work as one mass damper.

Figures 3 and 4 are the mass damper for large vibrations (]
, ), and the second spring (11) in the small vibration mass damper (8).
), and the second spring (11) increases in rigidity as it deforms to a certain extent, and becomes a so-called hard spring type spring that does not deform any further when it is no longer deformed to the limit deformation. (See Figure 3) The first spring (6) is a boat spring, and the first mass does not move until a force greater than the frictional force of the bearing (4) is applied.

(Effects of the Invention) As described above, the double mass damper according to the present invention does not move with small vibrations, but is capable of large deformation.
It is supported on the floor via bearings, and a damper is interposed between it and the same floor, and a spring is interposed between it and a rigid body erected on the same floor. On top of the mass damper for large vibrations with adjusted period and damping, a mass damper for small vibrations with adjusted natural period and damping that cannot be deformed greatly but can respond to small vibrations without friction or rattling. By mounting the mass of the mass damper via the laminated rubber, it is possible to construct a mass damper that is effective against large vibrations as well as small vibrations.

[Brief explanation of drawings]

FIG. 1 is a vertical cross-sectional view showing an embodiment of a double-type mass damper according to the present invention, a view taken along the arrow 1-1 in FIG. 2, a plan view thereof, and FIGS. 3 and 4. Spring characteristic diagrams of each spring for a mass damper for large vibrations and a mass damper for small vibrations, respectively. Figure 5 is a side view showing an example of a conventional mass damper for small vibrations, and Figure 6 is a diagram of a conventional mass damper for large vibrations. It is a perspective view showing an example. (1) Mass damper for large vibrations (2) First mass, (3) Floor, (4
)...Bearing, (5)...Wall, (6)...
・・First spring, (7)・・Damper (8)・
...Mass damper for small vibrations (9)...Second mass, (10)...Laminated rubber, (11)...Second spring, (12)...Damper Figure 1

Claims (1)

[Claims] 1. On the mass of the mass damper for large vibrations, which is supported on the floor via bearings, and has dampers and springs interposed between the same floor and four rigid bodies arranged on the floor.
A double mass damper characterized in that the mass of a mass damper for small vibrations whose natural period and damping have been adjusted is mounted via laminated rubber.