JPS6015924Y2 - Mounting structure of vibration damping composite metal plate - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a structure that solves the structural problem of mounting by bolting when a damping composite metal plate is used as a damping member in a structure that generates vibration or noise.

It is known that various noise regulations are in place to protect the environment in living and working environments, etc., but measures to reduce the generated noise include sound absorption and insulation for the generated sound, and measures to eliminate the source of the noise. There are two types of countermeasures against vibration: damping and vibration isolation.

Among these rain countermeasures, sound absorption and sound insulation can be dealt with with relatively simple design methods, so most sound reduction measures to date have been based on sound absorption and sound insulation methods, but noise regulations have become stricter. In line with this, recently, emphasis has been placed on measures to reduce sound at the sound source through vibration damping and vibration isolation as a more effective method.

The damping materials used in this vibration damping and vibration isolation method are as follows:
Various damping alloys, damping paints, etc. can be mentioned, but among these, a damping composite metal plate with a sandwich structure in which a viscoelastic substance is inserted between two metal plates has particularly high damping properties.
In addition, by appropriately selecting the viscoelastic material to be inserted, the best performance can be achieved under the conditions of use.Furthermore, the same processing method can be used for ordinary metal plates, making it extremely useful. It is also known that it is attracting attention as a material.

However, this vibration-damping composite metal plate has the following problems in its use.

That is, FIG. 1 illustrates the structure of the damping composite metal plate 3, and the metal plate 3 is composed of a metal plate 1 (for example, a steel plate), a viscoelastic material 2 (for example, a synthetic resin), and a metal plate 1 as shown in the figure. The viscoelastic material 2 has a structure in which metal plates (similar to the metal plate 1) are laminated in a sandwich-like manner, and the viscoelastic material 2 behaves elastically in response to dynamic stress according to the stress rate, but when static It is known that it behaves like a liquid in response to stress.

For this reason, as illustrated in FIG. 2, a noise countermeasure component 5 as shown in the figure is manufactured using this vibration damping composite metal plate 3, and this component 5 is installed as a vibration source or a structure located upstream of the vibration. 4, when the bolt 6 (with washer 7 intervening) is used to fasten and attach the bolt 6, the following problem occurs.

In other words, when fastening bolts, the bolts are generally tightened in a short time using an impact wrench or the like, so when the component 5 is fastened using the vibration-damping composite metal plate, a dynamic compressive force acts near the part. When the tightening is completed and left in this state, the compressive force becomes static, and therefore the metal plate 1°1
As shown in FIGS. 3 and 4, the viscoelastic substance sandwiched between
The viscoelastic substance 2 in contact with this is extruded from between the metal plates 1 and 1', and 8 in FIG. 4 indicates the extruded viscoelastic substance.

Usually, the thickness of this inserted viscoelastic material 2 is 0.1771
1171 or more, and as it is pushed out as shown in Figure 4, the axial stress of the bolt 6 decreases by several tens of percent, and when the structure 4 vibrates violently, the bolt 4 loosens.
This can eventually lead to problems such as falling off, which can lead to serious accidents.

The present invention was developed to solve these problems, and its feature is that it is a vibration-damping composite metal structure in which a viscoelastic material is interposed between metal plates in structures that generate vibration or noise. In those where plates are fastened with bolts,
The metal plate is attached to the structure via a packing having a low elastic modulus, and a hole larger than the outer diameter of the bolt head is formed in the metal plate, and a washer for regulating the tightening force is loosely fitted in several parts, The point is that the structure, the metal plate, and the packing are fastened through the washer.

The present invention will be described in detail below based on the illustrated embodiment.
6 each shows each embodiment of the present invention, and as shown in FIG. When fastening and fixing the noise control component 5 manufactured by the above-mentioned method to the structure 4 located upstream from the source of vibration or the vibration using bolts 6, first, in the embodiment shown in FIG. bolt 6
A hole 5a with a diameter larger than the outer diameter of the head 6a of the bolt 6 is formed at the fastening position, a washer 9' for regulating the tightening force is loosely fitted into this hole 5a, and the bolt 6 is tightened through the washer 9. It is screwed into the object 4 side and fastened, that is, the washer 9' is inserted into the hole 5a.
The plate has a sufficiently larger area than the plate, and its central part is a recessed part with a step so that it can be loosely fitted into the hole 5a, and the thickness of the washer 9' is the same as that of the part 5 for vibration damping. The thickness of the composite metal plate 3) is slightly thinner than the thickness of the composite metal plate 3, and the bolt 6 is tightened so that the head 6a of the bolt 6 is inserted into the recessed central part having the step, and the peripheral part of the washer 9' is tightened so that the part 5 The bolt 6 is tightened with a bolt 6 without directly pinching the component 5, and the component 5 is supported by a washer 9'.

Furthermore, in the present invention, when fastening the component 5 made of a damping composite metal plate to the structure 4, a packing 10 having a low elastic modulus is interposed between the structure 4 and the component 5 as shown in the figure.

The shape of the tightening force regulating washer 9' has the same effect as the tightening force regulating washer 11 shown in the embodiment in FIG. A bent portion may be provided in the peripheral portions that sandwich the component 5 to create a spring action, thereby making the component clamping more secure.If the washer 11 with such a shape is used, not only will support be ensured, but the viscoelastic material 2 Even if a portion of the bolt flows out from the periphery of the hole 5a, it is possible to maintain the bolt connection with less play.

As is clear from the above embodiments, the present invention has a bolt 6
is tightened to the structure 4 without sandwiching the damping composite metal plate part 5, and all the parts 5 are inserted into the hole 5a.
Tightening force regulating washers 9, 1 having a sufficiently larger area than
1, i.e. bolt 6, washer 9',
11. Since the structure 4 is fastened with metal touch, it is possible to prevent the viscoelastic substance 2 from flowing out and to suppress the decrease in the axial stress of the bolt 6 to a small level, thereby preventing the bolt 6 from loosening or falling off. It is possible to firmly and firmly support the component without causing any trouble, and therefore to strongly exhibit the vibration damping and vibration-proofing effect of the vibration-damping composite metal plate. Since the packing 10 with a low elastic modulus is interposed between the parts 4 and 4, it is possible to obtain sufficient airtightness and to provide stable and reliable support for the parts 5. This is an excellent product that can eliminate problems.

[Brief explanation of drawings]

Figure 1 is an explanatory diagram of a vibration-damping composite metal plate, Figures 2, 3 and 4 are cross-sectional views showing the conventional bolt tightening method of vibration-damping composite metal plates and the problems caused by this, and Figures 5 and 6 are Each is a cross-sectional view of an embodiment of the present invention. 1.1'... Metal plate, 2... Viscoelastic material, 3... Damping composite metal plate, 4... Structure, 5... ...Noise control parts, 6...Bolts, 9'. 1...Tightening force regulating washer, 5a...hole, 6a...bolt head.

Claims (1)

[Scope of utility model registration request] In a structure that generates vibration or noise, a vibration-damping composite metal plate in which a viscoelastic substance is interposed between the metal plates is fastened with bolts, and the metal plate is attached to the structure through a packing having a low elastic modulus. At the same time, a hole larger than the outer diameter of the bolt head is formed in the metal plate, a washer for regulating the tightening force is loosely fitted into the metal plate, and the structure, the metal plate, and the packing are fastened through the washer. The installation of the damping composite metal plate consisting of the structure.