Vibration control device

Abstract

To provide a vibration control device capable of reducing the thickness and the cost.SOLUTION: A vibration control device for controlling vibration in a vertical direction of a floor of a building includes a base plate, a weight member provided on the base plate to be freely displaceable in the vertical direction, a damping element for imparting damping force to vertical vibration of the weight member, and a spring element for energizing the weight member to an upper direction. The spring element is a plate spring arranged between the base plate and the weight member.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a vibration damping device to be installed in a floor structure. [Background technology]

[0002] There is known a technology for damping a structure using a vibration damping device. Patent Document 1 discloses a tuned mass damper (TMD) that is mainly suitable for damping horizontal vibration. In buildings, vertical vibration of the floor caused by people walking inside or vehicles running outside can be a problem. Patent Document 2 discloses a TMD that is mainly suitable for damping such vertical vibration. A vibration damping device such as a TMD is composed of a weight, a spring element, and a damping element, and when suppressing vertical vibration of a floor, its natural frequency is adjusted to be close to the natural frequency of the structural frame of the floor. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 4347737 [Patent Document 2] Patent No. 4503493 Summary of the Invention [Problem to be solved by the invention]

[0004] Vibration control devices that suppress vertical vibrations caused by walking, etc., require tuning to suit each individual structural frame, and are required to be thin, as they are installed in the narrow gap between the floor panel and the slab. In addition, the more units are installed, the greater the vibration control effect can be expected, but this also leads to increased costs.

[0005] An object of the present invention is to provide a vibration damping device that can be made thinner and less expensive. [Means for solving the problem]

[0006] According to the present invention, A vibration damping device that damps vertical vibrations of a floor of a building, A base plate; A weight member provided on the base plate so as to be displaceable in the vertical direction; A damping element that provides a damping force against vertical vibration of the weight member; A spring element that biases the weight member upward, The spring element is disposed in a gap between the base plate and the weight member. Band-shaped It is a leaf spring. the law of nature , One end of the leaf spring in the longitudinal direction is fixed to the base plate, and the other end is not fixed to the weight member but abuts against the weight member. The present invention provides a vibration damping device. Effect of the Invention

[0007] According to the present invention, it is possible to provide a vibration damping device that can be made thinner and less expensive. [Brief description of the drawings]

[0008] [Figure 1] 1A and 1B are a plan view and a front view of a vibration damping device according to one embodiment of the present invention. [Diagram 2] 1(A) is a cross-sectional view taken along line AA in FIG. 1(B), and FIG. 1(B) is a plan view of the vibration damping device with the weight member and one of the spring elements removed. [Diagram 3] (A) is a plan view of the spring element, and (B) is a cross-sectional view taken along line BB in Figure 3(A). [Figure 4] 1A is a plan view of another example of a spring element, and FIG. 1B is a plan view of another example of a spring element. [Diagram 5] 13 is a plan view of the vibration damping device with the weight member removed, showing another example of the arrangement of the spring elements. FIG. [Figure 6] 5A is a plan view of a vibration damping device with a weight member removed, showing another example of the arrangement of spring elements, and FIG. 5B is an explanatory diagram of another example of the spring elements. [Figure 7] FIG. 11 is an explanatory diagram of another example of a guide structure. [Figure 8](A) is a schematic diagram of the structural frame that is the subject of the simulation, and (B) is a diagram showing the simulation results. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, the embodiments will be described in detail with reference to the accompanying drawings. Note that the following embodiments do not limit the invention according to the claims, and not all combinations of features described in the embodiments are essential to the invention. Two or more features among the multiple features described in the embodiments may be arbitrarily combined. In addition, the same reference numbers are used for the same or similar configurations, and duplicated descriptions are omitted.

[0010] First Embodiment 1(A) and (B) are a plan view and a front view of a vibration damping device 1 according to one embodiment of the present invention, Fig. 2(A) is a cross-sectional view taken along line AA in Fig. 1(B), and Fig. 2(B) is a plan view of the vibration damping device 1 with the weight member 3 and one of the spring elements 5 removed. In each figure, arrows X and Y indicate two mutually perpendicular horizontal directions when the vibration damping device 1 is installed on the floor (e.g., a slab) of a building, and arrow Z indicates the up and down directions.

[0011] The vibration control device 1 is a TMD and includes a base plate 2, a weight member 3, a damping element 4, and a spring element 5. The vibration control device 1 has a flat rectangular parallelepiped shape, particularly a cubic shape, as a whole, and can be installed in a narrow gap between a floor panel and a slab of a building floor. By tuning the mass of the weight member 3, the damping characteristic of the damping element 4, and the spring constant of the spring element 5 to correspond to the structural frame of the floor, it is possible to control the vertical vibration of the floor.

[0012] The base plate 2 is a rectangular plate-like member that is placed on or fixed to the floor of a building. The weight member 3 is a rectangular plate-like member that is thicker than the base plate 2. In this embodiment, the base plate 2 and the weight member 3 have the same shape in a plan view, that is, a square. When multiple vibration control devices 1 are arranged in a matrix, a large number of vibration control devices 1 can be arranged comfortably in a smaller installation area.

[0013] The base plate 2 is provided with a guide shaft 6 as a guide structure for guiding the displacement of the weight member 3 relative to the base plate 2 in the Z direction. This guide also serves to prevent the weight member 3 from shifting sideways when a large horizontal force such as an earthquake acts. In this embodiment, a plurality of guide shafts 6 extending in the Z direction are erected at different positions on the base plate 2. The weight member 3 is formed with a hole 3a into which the guide shaft 6 is inserted. The relationship between the diameter D1 of the hole 3a and the diameter D2 of the guide shaft 6 is D1>D2, and the fit between the guide shaft 6 and the hole 3a is loose. The dimensional relationship between D1 and D2 is, for example, D1=D2+2 mm. Since the fit between the guide shaft 6 and the hole 3a is loose, the weight member 3 can be displaced in the X direction and the Y direction relative to the base plate 2 within the range of play between the guide shaft 6 and the hole 3a.

[0014] The damping element 4 provides a damping force against the vertical vibration of the weight member 3. In this embodiment, the damping element 4 is a block-shaped viscoelastic body, and examples of the viscoelastic body include acrylonitrile butadiene rubber, butyl rubber, and polyurethane. In this embodiment, the damping element 4 is fixed to the base plate 2, and one is provided at the center of the base plate 2. A plurality of damping elements 4 may be provided at different positions on the base plate 2. The damping element 4 is not fixed to the weight member 3, and is in contact with the bottom surface of the weight member 3. However, the damping element 4 may be fixed to the weight member 3 and in contact with the base plate 2. The damping element 4 is disposed in the gap S between the base plate 2 and the weight member 3. Since the damping element 4 is contained within the outer shape of the base plate 2 and the weight member 3, the vibration control device 1 can be made compact.

[0015] The spring element 5 biases the weight member 3 upward. In the present embodiment, a plurality of (four) spring elements 5 are provided, which are arranged at the four corners of the base plate 2 and fixed to the base plate 2. The spring elements 5 are not fixed to the weight member 3, but are in contact with the bottom surface of the weight member 3. However, the spring elements 5 may be fixed to the weight member 3 and in contact with the base plate 2.

[0016] The spring element 5 is a leaf spring, and is disposed in the gap S between the base plate 2 and the weight member 3. By using a leaf spring as the spring element 5, it is easier to fine-tune the spring constant compared to, for example, a coil spring that is generally used in TMDs, and furthermore, the spring element 5 can be disposed in the narrow gap S. Since the gap S is narrow, for the same overall height of the vibration damping device 1, the height of the weight member 3 can be made higher, and the mass of the weight member 3 can be increased. Furthermore, by disposing the spring element 5 in the gap S, the spring element 5 can be contained within the external dimensions of the base plate 2 and the weight member 3, and therefore the vibration damping device 1 can be made more compact.

[0017] In this way, the vibration damping device 1 of this embodiment can be made thinner and less expensive.

[0018] The spring element 5 will be further described with reference to Figures 3(A) and 3(B). Figure 3(A) is a plan view of the spring element 5, and Figure 3(B) is a cross-sectional view taken along line BB in Figure 3(A).

[0019] The spring element 5 of this embodiment is a band-shaped leaf spring having a rectangular shape in a plan view. One end 5a in the longitudinal direction of the spring element 5 is a fixed end fixed to the base plate 2, and the other end 5b is a free end that is not fixed to the bottom surface of the weight member 3 and is in contact with it, forming a cantilever spring. In the vibration damping device 1 of this embodiment, the weight member 3 is simply placed on the damping element 4 and the spring element 5 without being fixed thereto.

[0020] At one end 5a of the spring element 5, a plurality of mounting holes H1 to H4 are arranged in the longitudinal direction of the spring element 5, and are formed in two rows spaced apart in the width direction. At the base plate 2, a pair of mounting holes 2a for fixing the spring element 5 is formed. The fixing device 7 is inserted through one of the mounting holes H1 to H4 and the mounting hole 2a to fix the spring element 5 to the base plate 2. The fixing device 7 is, for example, a bolt, and the mounting hole 2a is, for example, a screw hole. In the example of FIG. 2(B), the mounting hole H2 is selected. The method of fixing the spring element 5 is not limited to the structure of this embodiment, and various structures can be adopted.

[0021] The spring element 5 extends obliquely from one end 5a to the other end 5b in a side view, and resists displacement of the weight member 3 in a direction approaching the base plate 2. The spring element 5 has an S-shape in a side view, with the one end 5a bent in a convex arc toward the base plate 2 side, and the other end 5b bent in a convex arc toward the weight member 3 side. The radius of curvature of the other end 5b is shorter than the radius of curvature of the one end 5a.

[0022] The other end 5b has its arc-shaped curved surface in contact with the bottom surface of the weight member 3. When the weight member 3 vibrates up and down, the contact position between the other end 5b and the weight member 3 shifts horizontally (in the X direction in this embodiment) on the curved surface as the weight member 3 rolls on the curved surface, thereby reducing the friction. In addition, in this embodiment, the weight member 3 can be displaced horizontally relative to the base plate 2 within the range of play between the guide shaft 6 and the hole 3a, so that the friction between the other end 5b and the weight member 3 can be reduced when the weight member 3 vibrates up and down.

[0023] In this embodiment, the longitudinal directions of the spring elements 5 are oriented in the same direction (X direction) in all four spring elements 5. When the weight member 3 vibrates up and down, the contact positions of the other ends 5b of the spring elements 5 and the weight member 3 shift in the same direction (X direction) in each spring element 5, thereby further reducing the friction.

[0024] One end 5a of the spring element 5 is also fixed with its arc-shaped curved surface in contact with the upper surface of the base plate 2. The mounting holes H1 to H4 are formed on the curved surface. By changing the mounting holes H1 to H4, the length (effective length of the spring) L between the fixed position of the spring element 5 on the base plate 2 and the abutting position on the weight member 3 changes. If the length L is short, the spring constant becomes large, and if the length L is long, the spring constant becomes significantly small. By selecting the mounting holes H1 to H4, it is possible to finely adjust the spring constant of the spring element 5 (selection of the mounting hole H3 is assumed in FIG. 3(B)). In addition, by selecting the mounting holes H1 to H4, the inclination θ and height H of the spring element 5 with respect to the base plate 2 can also be changed. The selection of the mounting holes H1 to H4 may be the same for the four spring elements 5, or may be different.

[0025] The natural frequency of the vibration damping device 1 is determined by the mass of the weight member 3 and the spring constant of the spring element 5. When the mass of the weight member 3 is determined, the spring element 5 is tuned. The spring element 5 can be roughly tuned by adjusting the plate thickness, overall length, width, and number of sheets. Then, final fine adjustment is possible by selecting the mounting holes H1 to H4.

[0026] Second Embodiment In the first embodiment, the spring element 5 is formed with mounting holes H1 to H4 to adjust its fixed position, but the mounting holes H1 to H4 may be replaced with elongated holes. Fig. 4(A) shows one example. In the illustrated example, two rows of elongated holes HL extending in the longitudinal direction are formed at one end 5a of the spring element 5, spaced apart in the width direction. In this configuration as well, the fixed position of the spring element 5 relative to the base plate 2 can be changed, as in the first embodiment.

[0027] <Third embodiment> In the first embodiment, the spring element 5 is fixed to the base plate 2, but it may be fixed to the weight member 3. In addition, the spring element 5 may be fixed to both the base plate 2 and the weight member 3.

[0028] <Fourth embodiment> As the spring element 5, multiple types of leaf springs with different spring constants may be prepared so that one can be selected according to the natural vibration frequency of the vibration damping device 1 required in design. FIG. 4(B) shows one example. In the illustrated example, three types of leaf springs 5A to 5C are prepared. The leaf springs 5A to 5C differ only in width, with leaf spring 5A being the narrowest and leaf spring 5C being the widest. The type of spring element 5 used in the vibration damping device 1 may be one type or multiple types.

[0029] FIG. 5 is a diagram showing an example in which multiple types of spring elements 5 are used, and is a plan view of the vibration damping device 1 with the weight member 3 removed. In the example shown, two each of leaf springs 5B and 5C are used. Combining leaf springs with different spring constants allows fine adjustment of the natural frequency. Furthermore, by preparing multiple types of leaf springs with different spring constants, it is possible to quickly respond to a variety of natural frequencies.

[0030] 6(A) shows yet another arrangement. In the illustrated example, the longitudinal directions of the four spring elements 5 are mixed, some of which are in the X direction and some in the Y direction. This arrangement can also be adopted.

[0031] However, it is believed that the arrangement of the spring element 5 of the first embodiment illustrated in Figure 2(B) is more advantageous than the example of Figure 6(A) in terms of friction between the weight member 3 and the spring element 5 when the weight member 3 vibrates up and down.

[0032] Sixth Embodiment Various configurations can be adopted for the spring element 5. FIG. 6(B) shows one example. The other end 5b of the spring element 5D in FIG. 6(B) is not bent in an arc shape but is linear, and the side view of the spring element 5D is J-shaped. In the case of this configuration, friction between the other end 5b and the bottom surface of the weight member 3 may increase during the up-and-down vibration of the weight member 3. However, it is possible to take measures such as increasing the play between the guide shaft 6 and the hole 3a to allow the weight member 3 to be displaced more significantly in the horizontal direction relative to the base plate 2.

[0033] Seventh Embodiment In the first embodiment, the guide shaft 6 loosely fitted in the hole 3a of the weight member 3 is exemplified as a guide structure for guiding the displacement of the weight member 3 in the Z direction relative to the base plate 2, but other structures can also be adopted. FIG. 7 shows one example. In the illustrated example, the weight member 3 is box-shaped with an open downward direction, and its peripheral portion 3b protrudes downward. The base plate 2 is box-shaped with an open upward direction, and its peripheral portion 2b protrudes upward. The peripheral portion 2b is inserted inside the peripheral portion 3b to guide the displacement of the weight member 3 in the Z direction relative to the base plate 2. The peripheral portion 2b is loosely fitted inside the peripheral portion 3b, so that the weight member 3 can be displaced in the horizontal direction relative to the base plate 2.

[0034] Eighth embodiment 8(A) is a diagram showing a model 100 of a structural frame that was the subject of a simulation to confirm the performance of a vibration control device 1. The illustrated model 100 is an assumed steel-frame office floor, and includes multiple columns 101, multiple girders 102, and a floor slab 103. A plurality of vibration control devices 1 are arranged on the floor slab 103, and in the illustrated example, 21 vibration control devices 1 are arranged in a matrix. The 21 vibration control devices 1 are arranged in the direction of the girder 102, at the center of the span (15 m), and are tuned to correspond to the natural frequency (6.4 Hz) of the floor.

[0035] Figure 8(B) shows the simulation results. When the vibration control device 1 is installed, the vibration value (accelerance) near the floor's natural frequency is reduced by about 60% compared to when the vibration control device 1 is not installed. Even when a leaf spring is used as the spring element 5 of the vibration control device 1, a sufficient vibration control effect is obtained.

[0036] Although the embodiment of the invention has been described above, the invention is not limited to the above embodiment, and various modifications and variations are possible within the scope of the gist of the invention. [Explanation of symbols]

[0037] 1 vibration damping device, 2 base plate, 3 weight member, 4 damping element, 5 spring element

Claims

1. A vibration damping device that damps vertical vibrations of a floor of a building, A base plate; A weight member provided on the base plate so as to be displaceable in the vertical direction; A damping element that provides a damping force against vertical vibration of the weight member; A spring element that biases the weight member upward, the spring element is a band-shaped leaf spring disposed in a gap between the base plate and the weight member, One end of the leaf spring in the longitudinal direction is fixed to the base plate, and the other end is not fixed to the weight member but abuts against the weight member. A vibration damping device characterized by:

2. 2. The vibration damping device according to claim 1, The damping element is a viscoelastic body disposed in a gap between the base plate and the weight member. A vibration damping device characterized by:

3. The vibration damping device according to claim 1 or 2, The one end of the leaf spring is bent into an arc shape, and the curved surface is abutted against and fixed to the base plate, The other end of the leaf spring is bent in an arc shape, and the curved surface of the curved surface abuts against the weight member. A vibration damping device characterized by:

4. The vibration damping device according to any one of claims 1 to 3, The spring element includes a plurality of the leaf springs, The plurality of leaf springs are fixed to different positions of the base plate and have longitudinal directions oriented in the same direction. A vibration damping device characterized by:

5. The vibration damping device according to any one of claims 1 to 4, The base plate includes a guide means for guiding the vertical displacement of the weight member relative to the base plate. A vibration damping device characterized by:

6. The vibration damping device according to claim 5, The guide means is a guide shaft provided upright on the base plate, and the weight member is formed with a hole into which the guide shaft fits loosely. A vibration damping device characterized by:

7. The vibration damping device according to any one of claims 1 to 6, The leaf spring is fixed to the base plate at the one end such that a fixed position thereof can be adjusted. A vibration damping device characterized by:

8. The vibration damping device according to any one of claims 1 to 3, The spring element includes a plurality of the leaf springs, The plurality of leaf springs are fixed to different positions of the base plate and include leaf springs having different widths. A vibration damping device characterized by:

Images