Underwater acoustic material

Abstract

To provide an underwater acoustic material that can be easily attached even if an attached curved surface is small in radius of curvature, and is advantageous in improving workability.SOLUTION: An underwater acoustic material 14A is formed by stacking a plurality of underwater acoustic material-made plate bodies 16 along a thickness direction, so even if an attached surface 12 of an underwater structure 10 is small in radius R of curvature, the underwater acoustic material 14A is easily made to deform following up the curved surface and can be easily attached, which is advantageous in improving the workability.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to underwater acoustic materials. [Background technology]

[0002] 2. Description of the Related Art Underwater acoustic materials have been provided that are attached to underwater structures such as the hull of a ship to achieve sound insulation, sound absorption, or vibration suppression (see Patent Document 1). One such underwater acoustic material is a rectangular plate made of an elastic material and of uniform thickness, and the underwater acoustic material is attached by superimposing on the mounting surface of the underwater structure one of its two thickness-wise surfaces, that is, the mounting surface. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2001-296873 A Summary of the Invention [Problem to be solved by the invention]

[0004] Incidentally, when the mounting surface is formed as a convex curved surface, the rectangular surface of the underwater acoustic material deforms to conform to the curved surface because the underwater acoustic material is formed from an elastic material. However, as the radius of curvature R of the surface to which the underwater acoustic material is to be attached becomes smaller, it becomes more difficult for the underwater acoustic material to deform to conform to the curved surface, which creates a problem that the work of attaching the underwater acoustic material becomes more difficult. In particular, when underwater acoustic materials are used in environments where they are subjected to high water pressure, in order to ensure both the durability and acoustic performance of the underwater acoustic material, it is necessary to use an elastic material that has a high hardness and is less susceptible to the effects of water pressure.However, if an elastic material with a high hardness is used to make the underwater acoustic material, the installation work of the underwater acoustic material becomes more difficult, and some kind of improvement is required. The present invention has been devised in consideration of the above-mentioned circumstances, and an object of the present invention is to provide an underwater acoustic material that can be easily installed and is advantageous in improving workability, even when the radius of curvature R of the curved surface to which it is attached is small. [Means for solving the problem]

[0005] In order to achieve the above-mentioned object, one embodiment of the present invention is a plate-shaped underwater acoustic material having a thickness and made of an elastic material that is attached to a mounting surface formed by a convex curved surface of an underwater structure, and is characterized in that the underwater acoustic material is formed by stacking a plurality of underwater acoustic material plates in the thickness direction. In addition, one embodiment of the present invention is characterized in that at least one of the plurality of underwater acoustic material boards has a JIS A hardness of 60 degrees or more and 90 degrees or less. In addition, one embodiment of the present invention is characterized in that the plurality of underwater acoustic material plates are integrally attached by adhesive. In addition, one embodiment of the present invention is characterized in that the thickness of each of the multiple underwater acoustic material plates is greater than or equal to 10 mm and less than or equal to 40 mm. In one embodiment of the present invention, the thicknesses of the plurality of underwater acoustic material plates are formed to gradually increase as they are separated from the mounting surface. In addition, one embodiment of the present invention is characterized in that the thickness of the multiple underwater acoustic material plates is greater for the underwater acoustic material plates that are arranged at a location away from the mounting surface than for the underwater acoustic material plates that are attached and arranged on the mounting surface. Effect of the Invention

[0006] According to one embodiment of the underwater acoustic material of the present invention, the underwater acoustic material is formed by stacking multiple underwater acoustic material plates in the thickness direction, so that even if the radius of curvature of the mounting surface of the underwater structure is small, the underwater acoustic material can be easily deformed to follow the curved surface, making it easy to install the underwater acoustic material and advantageous in improving workability. Furthermore, if at least one of the multiple underwater acoustic material plates has a JIS A hardness of 60 degrees or more and 90 degrees or less, this is advantageous in ensuring both the durability and acoustic performance of the underwater acoustic material when used in an environment where the underwater acoustic material is subjected to high water pressure, and in improving workability when attaching the underwater acoustic material to an underwater structure. Furthermore, if multiple underwater acoustic material plates are attached together with an adhesive, this is advantageous in maintaining the durability and acoustic performance of the underwater acoustic material for a long period of time. Furthermore, if the thickness t of each of the multiple underwater acoustic material plates is between 10 mm and 40 mm, this is advantageous in improving the workability when attaching the underwater acoustic material to an underwater structure and in improving the workability when manufacturing the underwater acoustic material. Furthermore, making the radius of curvature of the underwater acoustic material plate smaller the closer it is to the mounting surface of the underwater structure and larger the further it is from the mounting surface is advantageous in making it easier to deform the underwater acoustic material to follow the curved surface, and it also reduces the number of underwater acoustic material plates that make up the underwater acoustic material, which is advantageous in reducing the manufacturing costs of the underwater acoustic material. Furthermore, making the thickness of the underwater acoustic material plate that is placed away from the mounting surface greater than the thickness of the underwater acoustic material plate that is attached to the mounting surface is advantageous in making it easier to deform the underwater acoustic material to conform to the curved surface, and it is also advantageous in reducing the number of underwater acoustic material plates that make up the underwater acoustic material, thereby reducing the manufacturing costs of the underwater acoustic material. [Brief description of the drawings]

[0007] [Figure 1] 1 is a cross-sectional view showing a state in which an underwater acoustic material according to a first embodiment is attached to a mounting surface of an underwater structure. [Diagram 2] 11 is a cross-sectional view showing a state in which an underwater acoustic material according to a second embodiment is attached to a mounting surface of an underwater structure. FIG. [Diagram 3] 11 is a cross-sectional view showing a state in which an underwater acoustic material according to a third embodiment is attached to a mounting surface of an underwater structure. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] (First embodiment) First, an underwater acoustic material according to a first embodiment will be described with reference to FIG. The mounting surface 12 of an underwater structure 10 such as a ship's hull to which the underwater acoustic material 14A is attached is formed of a convex curved surface. In this embodiment, the curved surface is formed of a cylindrical surface with a radius of curvature R, for example.

[0009] The underwater acoustic material 14A is formed by stacking a plurality of underwater acoustic material plates 16 made of an elastic material in the thickness direction. In this embodiment, five rectangular underwater acoustic material plates 16 having the same thickness t are formed by stacking them in the thickness direction, and these underwater acoustic material plates 16 are, in order from the mounting surface 12, the first to fifth underwater acoustic material plates 16A, 16B, 16C, 16D, and 16E. The first to fifth underwater acoustic material plates 16A, 16B, 16C, 16D, and 16E each have two surfaces 20, 22 consisting of cylindrical surfaces at both ends in the thickness direction, and four flat end surfaces 24 connecting the four opposing sides of both surfaces 20, 22. When the first to fifth underwater acoustic material plates 16A, 16B, 16C, 16D, and 16E are stacked, their four end faces 24 are positioned on approximately the same plane. Each underwater acoustic material plate 16 has an attachment hole 1602 formed at each of its four corners, penetrating through the thickness direction, and when each underwater acoustic material plate 16 is stacked, these attachment holes 1602 are connected approximately on the same axis to form the attachment hole 18 of the underwater acoustic material 14A. As the elastic material constituting the first to fifth underwater acoustic plates 16A, 16B, 16C, 16D, and 16E, various conventionally known elastic materials such as rubber and urethane can be used. The thickness t of each of the multiple underwater acoustic material plates 16 is 10 mm or more and 40 mm or less. At least one of the multiple underwater acoustic material plates 16 has a JIS A hardness of 60 degrees or more and 90 degrees or less, and in this embodiment, the first to fifth underwater acoustic material plates 16A, 16B, 16C, 16D, and 16E are formed with the same hardness.

[0010] One of the surfaces 20, 22 in the thickness direction of the first underwater acoustic material plate 16A constitutes the mounting surface 26 of the underwater acoustic material 14A which is superimposed on and mounted on the mounting surface 12 of the underwater structure 10, and the other surface 22 is superimposed on surface 20 which is one of the surfaces 20, 22 in the thickness direction of the second underwater acoustic material plate 16B. Similarly, the second underwater acoustic material plate 16B, the third underwater acoustic material plate 16C, the fourth underwater acoustic material plate 16D, and the fifth underwater acoustic material plate 16E are stacked with each other with both sides 20, 22 in the thickness direction, and the side 22 opposite the fourth underwater acoustic material plate 16D of the fifth underwater acoustic material plate 16E, which is the farthest from the underwater structure 10, constitutes the outer surface 28 of the underwater acoustic material 14A. The underwater acoustic material 14A is constructed by first to fifth underwater acoustic material plates 16A, 16B, 16C, 16D, and 16E which are integrally attached with an adhesive.

[0011] The underwater acoustic material 14A is attached with its mounting surface 26 superimposed on the mounting surface 12 of the underwater structure 10, which is formed by a convex curved surface. The underwater acoustic material 14A is attached to the mounting surface 12 by passing a fastening member 30, consisting of a weld bolt or a stud bolt protruding from the mounting surface 12, through the mounting hole 18 of the underwater acoustic material 14A and connecting it to a nut N. In other words, the underwater acoustic material 14A is attached to the mounting surface 12 via a plurality of fastening members 30 which penetrate the underwater acoustic material 14A in the thickness direction and connect to the mounting surface 12, and the plurality of fastening members 30 are arranged at the four corners of the mounting surface 16. As the fastening member, various conventionally known members such as a bolt fastened to the female thread of the mounting surface 12 can be used. Furthermore, when attaching the underwater acoustic material 14A to the attachment surface 12, it is possible to employ various conventionally known attachment structures other than fastening members.

[0012] Next, a method for manufacturing the underwater acoustic material 14A and a method for attaching it to the underwater structure 10 will be described. (Method 1) A jig having a surface formed with the same radius of curvature R as the radius of curvature R of the mounting surface 12 of the underwater structure 10 is prepared in advance. Next, the first underwater acoustic material plate 16A is laid on the surface of the jig and attached using a mounting fixture, thereby deforming the first underwater acoustic material plate 16A along the radius of curvature R. Next, one surface 20 of the second underwater acoustic material plate 16B is superimposed tightly on the surface 22 of the first underwater acoustic material plate 16A opposite the jig using an adhesive. Similarly, the third underwater acoustic material plate 16C is attached to the second underwater acoustic material plate 16B, the fourth underwater acoustic material plate 16D is attached to the third underwater acoustic material plate 16C, and the fifth underwater acoustic material plate 16E is attached to the fourth underwater acoustic material plate 16D, each of which is overlapped and attached without any gaps using adhesive. The underwater acoustic material 14A is completed when the adhesive hardens while the first to fifth underwater acoustic material plates 16A, 16B, 16C, 16D, and 16E are overlapped, and the completed underwater acoustic material 14A is removed from the jig. The mounting surface 26 of the underwater acoustic material 14A is superimposed on the mounting surface 12 of the underwater structure 10 via a fastening member 30 and attached.

[0013] (Method 2) The first underwater acoustic material plate 16A is laid on the mounting surface 12 of the underwater structure 10 and attached using a mounting fixture, thereby deforming the first underwater acoustic material plate 16A along the radius of curvature R. Next, one surface 20 of the second underwater acoustic material plate 16B is superimposed tightly on the surface 22 of the first underwater acoustic material plate 16A opposite the jig using an adhesive. Similarly, the third underwater acoustic material plate 16C is attached to the second underwater acoustic material plate 16B, the fourth underwater acoustic material plate 16D is attached to the third underwater acoustic material plate 16C, and the fifth underwater acoustic material plate 16E is attached to the fourth underwater acoustic material plate 16D, each of which is overlapped and attached without any gaps using adhesive. The underwater acoustic material 14A is completed when the adhesive hardens while the first to fifth underwater acoustic material plates 16A, 16B, 16C, 16D, and 16E are overlapped, and the completed underwater acoustic material 14A is then overlapped and attached to the mounting surface 12 of the underwater structure 10 via the fastening members 30.

[0014] According to this embodiment, the underwater acoustic material 14A is formed by stacking multiple underwater acoustic material plates 16 in the thickness direction, so that even if the radius of curvature R of the mounting surface 12 of the underwater structure 10 is small, the underwater acoustic material 14A can be easily deformed to follow the curved surface, making it easy to attach the underwater acoustic material 14A and advantageous in improving workability. In addition, since there is no need to provide unevenness or grooves on the multiple underwater acoustic material plates 16 that form the underwater acoustic material 14A, this is advantageous in reducing manufacturing costs and simplifying the design.

[0015] Furthermore, in this embodiment, all of the multiple underwater acoustic material plates 16 have a JIS A hardness of 60 degrees or more and 90 degrees or less, which is advantageous in ensuring both the durability and acoustic performance of the underwater acoustic material 14A when used in an environment where the underwater acoustic material 14A is subjected to high water pressure. Furthermore, if the hardness of the underwater acoustic material plate 16 is less than JIS A 60 degrees, the effect of ensuring both the durability and acoustic performance of the underwater acoustic material 14A will be reduced when the underwater acoustic material 14A is used in an environment where it is subjected to high water pressure. Furthermore, if the hardness of the underwater acoustic material plate 16 exceeds JIS A90 degrees, the effect of easily deforming to follow the curved surface of the underwater acoustic material 14A decreases. The above effect can be achieved even if at least one of the multiple underwater acoustic material plates 16 has a JIS A hardness of 60 degrees or more and 90 degrees or less, but the present embodiment is more advantageous in achieving the above effect.

[0016] Furthermore, in this embodiment, since the multiple underwater acoustic material plates 16 are attached together with an adhesive, it is possible to prevent the multiple underwater acoustic material plates 16 from returning to their pre-deformation shape (flat shape) over time, which in turn prevents gaps from occurring between the underwater acoustic material plates 16, which is advantageous in maintaining the durability and acoustic performance of the underwater acoustic material 14A over a long period of time.

[0017] In addition, in this embodiment, the thickness t of each of the multiple underwater acoustic material plates 16 is set to be 10 mm or more and 40 mm or less, so that the underwater acoustic material 14A can be easily deformed to conform to curved surfaces, making it easier to attach the underwater acoustic material 14A and advantageous for improving workability. In addition, the number of underwater acoustic material plates 16 that make up the underwater acoustic material 14A can be reduced, which is advantageous for improving workability during the manufacture of the underwater acoustic material 14A. If the thickness t of each of the underwater acoustic material plates 16 is less than 10 mm, the number of underwater acoustic material plates 16 constituting the underwater acoustic material 14A increases, reducing workability during manufacture of the underwater acoustic material 14A. If the thickness t of each of the underwater acoustic material plates 16 exceeds 40 mm, the effect of easily deforming to follow the curved surface of the underwater acoustic material 14A decreases.

[0018] (Second embodiment) Next, an underwater acoustic material 14B according to a second embodiment will be described with reference to FIG. In the following embodiment, the same parts and members as those in the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted, and the description will focus on the differences. In the second embodiment, the underwater acoustic material 14B is formed by stacking four underwater acoustic material plates 16 in their thickness direction, and these underwater acoustic material plates 16 are, in order from the mounting surface 12, first to fourth underwater acoustic material plates 16A, 16B, 16C, and 16D. Another difference from the first embodiment is that the thicknesses of the multiple underwater acoustic material plates 16 are gradually increased as they move away from the mounting surface 12 . That is, when the thicknesses of the first to fourth underwater acoustic plate bodies 16A, 16B, 16C, and 16D are t1, t2, t3, and t4, t1 <t2<t3<t4としたものである。

[0019] According to the second embodiment, in addition to the same effects as those of the first embodiment, the following effects are achieved. With the underwater acoustic material 14B attached to the mounting surface 12 of the underwater structure 10, the radius of curvature of the underwater acoustic material plate 16 becomes smaller the closer it is to the mounting surface 12 of the underwater structure 10 and becomes larger the farther it is from the mounting surface 12. Therefore, by making the thickness of the underwater acoustic material plate 16 smaller the closer it is to the mounting surface 12 of the underwater structure 10, it is advantageous in making it easier for the underwater acoustic material 14B to deform to follow the curved surface. In addition, by increasing the thickness of the underwater acoustic material plate 16 the further away from the mounting surface 12 of the underwater structure 10, the number of underwater acoustic material plates 16 that form the underwater acoustic material 14B can be reduced, which is advantageous in reducing the manufacturing costs of the underwater acoustic material 14B.

[0020] (Third embodiment) Next, an underwater acoustic material 14C according to a third embodiment will be described with reference to FIG. In the third embodiment, similarly to the second embodiment, the underwater acoustic material 14C is formed by stacking four rectangular underwater acoustic material plates 16 in their thickness direction, and these underwater acoustic material plates 16 are numbered first to fourth underwater acoustic material plates 16A, 16B, 16C, and 16D, in order from the mounting surface 12. In the third embodiment, the thickness of the fourth underwater acoustic material plate 16D disposed at a position away from the mounting surface 12 is greater than the thickness of the first underwater acoustic material plate 16A disposed on the mounting surface 12, and when the thicknesses of the first to fourth underwater acoustic material plates 16A, 16B, 16C, and 16D are t1, t2, t3, and t4, respectively, t1 <t2=t3<t4としたものである。

[0021] According to the third embodiment, in addition to the same effects as those of the first embodiment, the following effects are achieved. Making the thickness of the first underwater acoustic material plate 16A closest to the mounting surface 12 of the underwater structure 10 the smallest is advantageous in making it easier for the underwater acoustic material 14C to deform to follow the curved surface. Furthermore, by making the thickness of the fourth underwater acoustic material plate 16D, which is the farthest from the mounting surface 12 of the underwater structure 10, the number of underwater acoustic material plates 16 that form the underwater acoustic material 14C can be reduced, which is advantageous in reducing the manufacturing costs of the underwater acoustic material 14C. In the third embodiment, the thicknesses t2 and t3 of the second and third underwater acoustic material plates 16B and 16C, excluding the first and fourth underwater acoustic material plates 16A and 16D, are made the same. Although the thicknesses t2 and t3 do not have to be the same, making the thicknesses t2 and t3 the same makes it easier to manufacture the second and third underwater acoustic material plates 16B and 16C, which is advantageous in reducing costs.

[0022] The lower limit of the radius of curvature R of the mounting surface 12 of the underwater structure 10 to which the underwater acoustic materials 14A, 14B, and 14C of the embodiment can be attached is approximately 700 mm. [Explanation of symbols]

[0023] 10 Underwater structures 12. Mounting surface of underwater structure 14A underwater acoustic material 14B Underwater acoustic material 14C underwater acoustic material 16 Underwater acoustic material panel 16A No. 1 Underwater acoustic material plate 16B Second underwater acoustic material plate 16C 3rd Underwater Acoustic Material Plate 16D No. 4 Underwater acoustic material plate 16E No. 5 Underwater acoustic material plate 1602 Mounting hole 18 Underwater acoustic material mounting hole 20, 22 both sides 24 End face 26 Mounting surface for underwater acoustic material 28 Outer surface of underwater acoustic material 30 Fastening members N Nut

Claims

1. A plate-shaped underwater acoustic material having a thickness and made of an elastic material, which is attached to a mounting surface formed by a convex curved surface of an underwater structure, The underwater acoustic material is formed by stacking a plurality of underwater acoustic material plates in the thickness direction. An underwater acoustic material characterized by:

2. At least one of the plurality of underwater acoustic material plates has a hardness JIS A of 60 degrees or more and 90 degrees or less.

2. The underwater acoustic material according to claim 1.

3. The plurality of underwater acoustic material plates are attached together by adhesive.

2. The underwater acoustic material according to claim 1.

4. The thickness of each of the plurality of underwater acoustic material plates is 10 mm or more and 40 mm or less.

2. The underwater acoustic material according to claim 1.

5. The thicknesses of the plurality of underwater acoustic material plates are formed to be gradually larger as they are separated from the mounting surface.

2. The underwater acoustic material according to claim 1.

6. The thickness of the plurality of underwater acoustic material plates is larger in the underwater acoustic material plates disposed at a position away from the mounting surface than in the underwater acoustic material plates disposed to be attached to the mounting surface.

2. The underwater acoustic material according to claim 1.

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