JP2022039913A - Vibration suppression device - Google Patents

Abstract

To provide a vibration suppression device which achieves excellent destruction inhibition performance of high-damping rubber when the vibration suppression device is operated and large deformation occurs repeatedly.SOLUTION: A vibration suppression device includes: a first plate; a second plate facing one major surface of the first plate; high-damping rubber disposed between the first plate and the second plate and bonded to the first plate and the second plate; and cover rubber which covers an outer peripheral surface of the high-damping rubber. The cover rubber is spaced apart from the first plate and the second plate.SELECTED DRAWING: Figure 1

Description

The present invention relates to a vibration damping device.

As a vibration damping device for structures such as buildings and bridges, a vibration damping device including a pair of plates and a high damping rubber interposed between the plates is known (see, for example, Patent Document 1). As described in Patent Document 1, a diene-based rubber is generally used as the high damping rubber. Since this diene-based rubber tends to deteriorate over time, the outer peripheral surface of the highly damped rubber is covered with a rubber layer having high weather resistance. Butyl rubber is preferably used for this coated rubber layer because it has excellent gas barrier properties and damping performance. The high damping rubber and the coated rubber layer are usually vulcanized and bonded to the plate.

Japanese Unexamined Patent Publication No. 2012-126818

As a result of diligent studies by the present inventors, it has been found that in the conventional vibration damping device, there is room for improvement in the breakage suppressing performance of the high damping rubber when the vibration damping device is operated and repeated large deformation occurs. I found it. Therefore, it is an object of the present invention to provide a vibration damping device having excellent fracture suppressing performance of high damping rubber when the vibration damping device is operated and large deformation is repeatedly generated.

The vibration damping device disclosed herein is arranged between the first plate, the second plate facing one main surface of the first plate, and the first plate and the second plate, and the first plate. A high damping rubber bonded to the 1 plate and the 2nd plate, and a coated rubber covering the outer peripheral surface of the high damping rubber are provided. The coated rubber is arranged apart from the first plate and the second plate.

According to such a vibration damping device, the fracture suppressing performance of the high damping rubber is improved when the vibration damping device is operated and large deformation is repeatedly generated.

FIG. 1 is a partially cutaway perspective view showing an embodiment of the vibration damping device disclosed here. FIG. 2 is a partial cross-sectional view of an embodiment of the vibration damping device disclosed here. FIG. 3 is a schematic cross-sectional view for explaining a first example of the manufacturing method of the vibration damping device disclosed here. FIG. 4 is a schematic cross-sectional view for explaining a second example of the manufacturing method of the vibration damping device disclosed here. FIG. 5 is a schematic cross-sectional view for explaining a third example of the manufacturing method of the vibration damping device disclosed here. FIG. 6 is a perspective view of a core member and an end member used in one embodiment of the third example of the method for manufacturing a vibration damping device disclosed herein. FIG. 7 is a perspective view of a core member and another end member used in one embodiment of the third example of the method of manufacturing a vibration damping device disclosed herein. FIG. 8 is a schematic explanatory view of a testing machine for displacing the test bodies of Examples and Comparative Examples to obtain the relationship between the displacement amount and the load. FIG. 9 is a graph showing an example of a hysteresis loop showing the relationship between the displacement amount and the load, which is obtained by displacing the test piece using the test machine of FIG.

Hereinafter, the vibration damping device disclosed here will be described with reference to the drawings. The present invention is not limited to the following embodiments. Each drawing is drawn schematically and does not necessarily reflect the real thing. Further, each drawing shows only one example, and does not limit the present invention unless otherwise specified. Further, members / parts having the same action are appropriately designated with the same reference numerals, and duplicate description will be omitted.

FIG. 1 is a partially cutaway perspective view showing an embodiment of the vibration damping device disclosed here. FIG. 2 is a partial cross-sectional view of an embodiment of the vibration damping device disclosed herein, and shows a part of a cross section taken along the line IV-IV of FIG. The vibration damping device 10 disclosed here includes a first plate 11, a second plate 12, a high damping rubber 13, and a coated rubber 14, as shown in FIGS. 1 and 2. .. The second plate 12 faces one main surface of the first plate 11. As used herein, the "main surface of the plate" refers to two opposing surfaces having the largest area among the surfaces of the plate.

For the first plate 11 and the second plate 12, a metallic plate having a required rigidity, for example, a steel plate or an aluminum plate having a required thickness and rigidity is used. The first plate 11 and the second plate 12 are usually configured to be incorporated into a viscoelastic damper or the like, and have, for example, a bolt mounting hole or the like.

The high damping rubber 13 is arranged between the first plate 11 and the second plate 12. In other words, the high damping rubber 13 is sandwiched by the first plate 11 and the second plate 12. Therefore, when each surface of each member of the vibration damping device 10 corresponds to the "upper" and "lower" in FIG. 2, the upper surface of the high damping rubber 13 comes into contact with the lower surface of the first plate 11, and the high damping rubber 13 The lower surface is in contact with the upper surface of the second plate 12. The high damping rubber 13 is adhered to the first plate 11 and the second plate 12, and is usually vulcanized. The high damping rubber 13 is usually adhered to the first plate 11 and the second plate 12 in all of their contact areas, but only a part of the contact area may be adhered. When an earthquake occurs and the first plate 11 and the second plate 12 vibrate, the high damping rubber 13 deforms and can suppress the propagation of vibration to structures such as buildings and bridges, and also has high damping. The vibration can be damped by the damping action of the rubber 13.

The high damping rubber 13 is a viscoelastic body having a higher damping property than the coated rubber 14, and may contain a diene rubber as a rubber component. The type of the diene-based rubber is not particularly limited, and may be a known diene-based rubber used as a high damping rubber. The diene rubber is preferably at least one rubber selected from the group consisting of natural rubber, isoprene rubber (IR), butadiene rubber (BR), and styrene butadiene rubber (SBR). The high damping rubber 13 may further contain a component other than the rubber component. For example, the high damping rubber 13 may further contain additives such as silica and carbon black that exhibit high damping properties.

In the embodiment shown in FIG. 1, the high damping rubber 13 has a rectangular parallelepiped shape, but as long as the shape of the high damping rubber 13 is arranged between the first plate 11 and the second plate 12. Not particularly limited. The high damping rubber 13 may have a cubic shape or a polygonal pillar shape other than the square pillar shape. The high damping rubber 13 may have a cylindrical shape. The high-damping rubber 13 may be composed of a single member made of high-damping rubber, or may be formed by adhering two or more members made of high-damping rubber. For example, in the high damping rubber 13, a plurality of elongated rectangular parallelepiped high damping rubber parts are arranged in one direction so as to form a square columnar shape, and the high damping rubber parts are bonded to each other by vulcanization adhesion or the like. It may be there.

Of the surfaces of the high damping rubber 13, the surfaces that are not in contact with the first plate 11 and the second plate 12 constitute the outer peripheral surface. In the embodiment shown in FIG. 1, the outer peripheral surface is composed of four rectangular surfaces. The outer peripheral surface may be a curved surface depending on the embodiment, for example, when the high damping rubber 13 has a cylindrical shape.

As shown in FIGS. 1 and 2, in the vibration damping device 10 which is one embodiment of the vibration damping device disclosed here, the outer peripheral surface of the high damping rubber 13 is the end portion on the first plate 11 side. It also has a first convex portion 13a. Further, the outer peripheral surface of the high damping rubber 13 has a second convex portion 13b at an end portion on the second plate 12 side. In the illustrated embodiment, the outer peripheral surface of the high damping rubber 13 has a first convex portion 13a and a second convex portion 13b over the entire circumference thereof. However, the outer peripheral surface of the high damping rubber 13 may have a first convex portion 13a and a second convex portion 13b in a part thereof.

As shown in FIG. 2, of the outer peripheral surface of the high damping rubber 13, the outer peripheral surface 13c between the first convex portion 13a and the second convex portion 13b of the high damping rubber 13 is covered with the coated rubber 14. Has been done. The coated rubber 14 is layered, has weather resistance and air barrier properties, and has an effect of suppressing aging deterioration of the highly damped rubber. As the rubber component of the coated rubber 14, for example, ethylene propylene rubber, chloroprene rubber, or butyl rubber can be used. The type of butyl rubber is not particularly limited, and may be a known butyl rubber used as a covering rubber for high damping rubber. The butyl rubber is preferably at least one kind of rubber selected from the group consisting of brominated butyl rubber and chlorinated halogenated butyl rubber. The coated rubber 14 is usually vulcanized together with the high damping rubber 13.

On the other hand, the coated rubber 14 does not cover the top of the first convex portion 13a and the top of the second convex portion 13b. Therefore, the coated rubber 14 is separated from the first plate 11 and the second plate 12 by the first convex portion 13a and the second convex portion 13b. Therefore, the coated rubber 14 is not adhered to the first plate 11 and the second plate 12. Only the high damping rubber 13 is arranged near the first plate 11 and the second plate 12, and only the high damping rubber 13 is adhered to the first plate 11 and the second plate 12. be.

The shapes of the first convex portion 13a and the second convex portion 13b are not particularly limited as long as the covering rubber 14 can be separated from the first plate 11 and the second plate 12. As shown in FIG. 2, when the first convex portion 13a and the second convex portion 13b have a rectangular cross-sectional shape, the design and manufacture of the vibration damping device is particularly easy.

Here, in the prior art, the high damping rubber may be broken when the vibration damping device is operated and a large deformation is repeatedly generated. The mechanism when this destruction occurs is considered as follows. In the prior art, the plate is in contact with and adhered to both high damping rubber and coated rubber. When the vibration damping device is activated and repeated large deformation occurs, the high damping rubber and the coated rubber receive the maximum stress near the plate. Therefore, in the vicinity of the plate, large elongation and large compression occur in both the high damping rubber and the coated rubber in contact with the plate. Since the high damping rubber is a viscoelastic body and the coated rubber is an elastic body, there is a difference in deformation. This causes peeling between the high damping rubber and the coated rubber, between the coated rubber and the plate, and between the high damping rubber and the plate. Then, by repeating stretching and compression, the rubber repeatedly adheres to and peels off from each other, and the destruction of the highly damped rubber progresses.

On the other hand, in the vibration damping device 10 which is one embodiment of the vibration damping device disclosed here, as described above, only the high damping rubber 13 is arranged in the vicinity of the plate 11 and the plate 12 where the stress is concentrated. The coated rubber 14 is separated from the first plate 11 and the second plate 12. Therefore, when the vibration damping device 10 is operated and large deformation is repeatedly generated, the stress applied to the coated rubber 14 can be significantly reduced, and the destruction of the highly damped rubber can be highly suppressed.

The dimension of the convex portion 13a of the high damping rubber 13 in the direction perpendicular to the main surface of the first plate 11 (that is, the dimension A in FIG. 2), and the dimension of the convex portion 13b of the high damping rubber 13 on the main surface of the second plate 12. The dimensions in the vertical direction (that is, the dimension B in FIG. 2) are not particularly limited, and are, for example, 0.75 mm or more, respectively. The larger the dimension A and the dimension B, the more the stress applied to the above-mentioned coated rubber 14 can be reduced at a higher level, and the fracture suppressing performance of the high damping rubber becomes higher. Therefore, from the viewpoint of the higher damping performance of the high damping rubber, the vibration damping device 10 has a configuration in which the dimensions A and B are each 1.5 mm or more. The dimensions of the high damping rubber 13 other than the first convex portion and the second convex portion (for example, the overall dimensions of the high damping rubber 13) are not particularly limited, and are the same as the high damping rubber of the known vibration damping device. It may be there.

In the illustrated example, the covering rubber 14 completely fills the space between the convex portion 13a and the convex portion 13b of the high damping rubber 13 (in other words, the covering rubber 14 completely fills the concave portion on the side surface of the high damping rubber 13). The coated rubber 14 completely covers the outer peripheral surface 13c between the first convex portion 13a and the second convex portion 13b of the high damping rubber 13). However, the coated rubber 14 may partially fill the space between the convex portion 13a and the convex portion 13b of the high damping rubber 13 to partially cover the outer peripheral surface 13c.

The coverage ratio of the high damping rubber 13 by the covering rubber 14 is not particularly limited, but the larger the covering ratio, the more oxygen and the like can be prevented from entering the high damping rubber 13, and the aged deterioration can be further suppressed. .. Therefore, from the viewpoint of high deterioration suppressing performance, the vibration damping device 10 is configured such that the covering rubber covers 50% or more of the dimension between the first plate 11 and the second plate 12 of the high damping rubber 13. That is, with respect to the dimensions in FIG. 2, the value (%) obtained from the dimensions C / (dimension A + dimension C + dimension B) × 100 is configured to be 50% or more. The dimension C is the dimension of the coated rubber 14 in the direction perpendicular to the main surface of the first plate 11 and the main surface of the second plate 12. Therefore, the upper limits of the dimension A and the dimension B can be appropriately set from this viewpoint.

Therefore, in the vibration damping device 10, the dimensions of the first convex portion 13a in the direction perpendicular to the main surface of the first plate 11 and the second convex portion 13b in the direction perpendicular to the main surface of the second plate 12. The dimensions are 1.5 mm or more, respectively, and the covering rubber 14 covers 50% or more of the dimensions between the first plate 11 and the second plate 12 of the high damping rubber 13, so that the high damping rubber is destroyed. It is possible to achieve a high degree of balance between suppression and suppression of aging deterioration.

The protruding lengths of the first convex portion 13a and the second convex portion 13b (that is, the left-right dimensions of the first convex portion 13a and the second convex portion 13b in FIG. 2, and the dimensions from the top to the bottom of the convex portions. ) Is not particularly limited. The protruding lengths of the first convex portion 13a and the second convex portion 13b may be the same as or different from the thickness of the coated rubber 14 (that is, the lateral dimension of FIG. 2 of the coated rubber 14), and are the same. It is preferable to have. The protruding lengths of the first convex portion 13a and the second convex portion 13b are, for example, 0.5 mm or more and 15 mm or less, particularly 1 mm or more and 5 mm or less. The thickness of the coated rubber 14 is not particularly limited. From the viewpoint of preventing oxygen and the like from entering the high damping rubber 13, it may be appropriately set according to the type of the material constituting the coated rubber 14. The thickness of the coated rubber 14 is, for example, 0.5 mm or more and 15 mm or less, particularly 1 mm or more and 5 mm or less.

Next, some examples of the manufacturing method of the vibration damping device 10 will be described. As a first example, the vibration damping device 10 can be manufactured as follows. FIG. 3 is a schematic cross-sectional view for explaining the first example of the manufacturing method. First, the unvulcanized high-damping rubber composition is processed into a predetermined shape to produce a core member 310 for the high-damping rubber 13. This predetermined shape is a shape obtained by removing the first convex portion 13a and the second convex portion 13b from the high damping rubber 13 exemplified in FIGS. 1 and 2.

On the other hand, the unvulcanized high-damping rubber composition is processed into a shape corresponding to the first convex portion 13a and a shape corresponding to the second convex portion 13b, and the convex portion member 320 for the high-damping rubber 13. Make 330 respectively. Further, the unvulcanized coated rubber composition is processed into a long sheet to prepare a sheet member 340 for the coated rubber 14.

A sheet member 340 for the coated rubber 14 is wound around the outer periphery of the core member 310 for the high damping rubber 13, and the wound sheet member 340 is sandwiched between the convex member members 320 and 330 to produce a rubber composite. Alternatively, the sheet member 340 for the coated rubber 14 is sandwiched between the convex portion members 320 and 330 and wound around the outer periphery of the core member 310 to prepare a rubber composite.

A vulcanizing adhesive is applied to the surfaces of the rubber composite in contact with the first plate 11 and the second plate 12, and the rubber composite is sandwiched between the first plate 11 and the second plate 12. This is heated to vulcanize the highly damped rubber composition and the coated rubber composition, and to bond them with a vulcanizing adhesive. Thereby, the vibration damping device 10 can be obtained.

As a second example, the vibration damping device 10 can be manufactured as follows. FIG. 4 is a schematic cross-sectional view for explaining a second example of the manufacturing method. The unvulcanized high-damping rubber composition is processed into a predetermined shape to produce a core member 410 for the high-damping rubber 13. This predetermined shape is a shape obtained by removing the upper portion including the first convex portion 13a and the lower portion including the second convex portion 13b from the high damping rubber 13.

On the other hand, the unvulcanized high-damping rubber composition is applied to the sheet members 420 and 420 having a main surface having a larger area by the amount of the first convex portion 13a and the second convex portion 13b than the upper surface and the lower surface of the core member 410. To make. These sheet members 420 and 420 have shapes corresponding to the upper portion including the first convex portion 13a and the lower portion including the second convex portion 13b, respectively.

The core member 410 is sandwiched between the sheet members 420 and 430 from the upper surface and the lower surface thereof. At this time, since the main surfaces of the sheet members 420 and 430 are larger than the upper surface and the lower surface of the core member, respectively, the portions of the sheet members 420 and 430 protruding from the core member are the first convex portion 13a and the second convex portion, respectively. It becomes 13b, and the unvulcanized high-damping rubber 13 is obtained.

Further, the unvulcanized coated rubber composition is processed into a long sheet to prepare a sheet member 440 for the coated rubber 14. The sheet member 440 for the coated rubber 14 is wound around a portion between the first convex portion 13a and the second convex portion 13b of the unvulcanized high damping rubber 13 to prepare a rubber composite.

A vulcanizing adhesive is applied to the surfaces of the rubber composite in contact with the first plate 11 and the second plate 12, and the rubber composite is sandwiched between the first plate 11 and the second plate 12. This is heated to vulcanize the highly damped rubber composition and the coated rubber composition, and to bond them with a vulcanizing adhesive. Thereby, the vibration damping device 10 can be obtained.

As a third example, the vibration damping device 10 can be manufactured as follows. FIG. 5 is a schematic cross-sectional view for explaining a third example of the manufacturing method. The unvulcanized high-damping rubber composition is processed into a predetermined shape to prepare a core member 510 for the high-damping rubber 13. This predetermined shape is a shape in which the end portion including the first convex portion 13a and the second convex portion 13b is removed from the high damping rubber 13.

On the other hand, the unvulcanized high-damping rubber composition has a shape corresponding to the end portion including the first convex portion 13a and the second convex portion 13b from the high-damping rubber 13 (in the illustrated example, a U-shaped cross section). To produce an end member 520 having a recess.

The unvulcanized coated rubber composition is processed into a long sheet to prepare a sheet member 540 for the coated rubber 14. The end member 520 is arranged on the outer peripheral surface of the core member 510, and the sheet member 540 is further arranged in the recess of the end member 520 to prepare a rubber complex.

A vulcanizing adhesive is applied to the surfaces of the rubber composite in contact with the first plate 11 and the second plate 12, and the rubber composite is sandwiched between the first plate 11 and the second plate 12. This is heated to vulcanize the highly damped rubber composition and the coated rubber composition, and to bond them with a vulcanizing adhesive. Thereby, the vibration damping device 10 can be obtained.

FIG. 6 shows an example of one form of the core member 510 and the end member 520 used in the third example of the manufacturing method of the vibration damping device 10. As shown in FIG. 6, as the core member 510 for the high damping rubber 13, a part member 512 obtained by processing an unvulcanized high damping rubber composition into a plurality of elongated rectangular parallelepiped shapes is prepared, and this is formed into a predetermined shape. After arranging in one direction so as to be, it may be formed by bonding or the like. Core members in other manufacturing methods may also be formed in this way. At this time, there is an advantage that the large-sized high-damping rubber 13 can be easily manufactured.

Here, when arranging the part members 512, air may enter between the mating surfaces 514 of the part members 512. In the first example and the second example described above, in the core member, the end of the mating surface 514 is exposed because it is located on the outer peripheral surface. As a result, the air that has entered the mating surface 514 can be discharged from the exposed end of the mating surface.

On the other hand, in the case of the third example described above, since the end member 520 is arranged on the outer peripheral surface of the core member 510, the end of the mating surface 514 is covered with the end member 520 and is not exposed. Therefore, the air that has entered the mating surface 514 tends to remain, and the remaining air expands during heating for adhesion, vulcanization, or the like, which may lead to defects.

Therefore, it is preferable to provide the opening 520 at a position where the end of the mating surface 514 is exposed on the end member 520 having a U-shaped cross section. The opening 520 allows the air that has entered the mating surface 514 to be discharged. In the illustrated example, the same number of openings 520 as the mating surfaces 514 are provided. Therefore, the number of edges of the mating surface 514 exposed by one opening 520 is one. However, the form of the opening 520 is not limited to this, and one opening 520 may expose the ends of the plurality of mating surfaces 514. Further, in the illustrated example, the opening shape of the opening 520 is circular, but the opening shape is not limited to this, and may be a square or the like. Therefore, although a modification of the end member 520 is shown in FIG. 7, for example, as shown in FIG. 7, the opening 522'of the end member 520'is a rectangular penetration that exposes the ends of the plurality of mating surfaces 514. It may be a hole.

The manufacturing method described above is an example, and the vibration damping device 10 can be manufactured by another method. For example, the high damping rubber composition is directly molded into the shape of the high damping rubber, and the sheet member for the coated rubber 14 is arranged on the outer peripheral surface to prepare a rubber composite, and the vibration damping device is used using this rubber composite. 10 can be manufactured. For example, the high damping rubber composition is formed into a rectangular parallelepiped shape or a cylindrical shape to form a groove on the outer peripheral surface, and a sheet member for the coated rubber 14 is arranged in the groove to prepare a rubber composite. The vibration damping device 10 can be manufactured using the body.

The vibration damping device 10 can be used for a viscoelastic damper or the like according to a known method or the like. Since the vibration damping device 10 is excellent in the fracture suppressing performance of the high damping rubber, the viscoelastic damper provided with the vibration damping device 10 is advantageous for high strain deformation due to a plurality of earthquakes.

Although the embodiment of the vibration damping device disclosed here has been described above, the vibration damping device disclosed here is not limited to the above-described embodiment. For example, in the above embodiment, the coated rubber is arranged apart from the first plate and the second plate by the first convex portion and the second convex portion on the outer peripheral surface of the high damping rubber, but the coated rubber is provided. The form separated from the first plate and the second plate is not limited to this, and for example, the coated rubber is provided with another member instead of the first convex portion and the second convex portion on the outer peripheral surface of the high damping rubber. The first plate and the second plate may be separated from each other, or the coating rubber and the first plate and the second plate may be formed so that the coating rubber does not cover the vicinity of the plate on the outer peripheral surface of the high damping rubber. It may be in the form of being separated from the plate of.

Further, for example, in the vibration damping device, high damping rubber is arranged on both main surfaces of one intermediate plate, and is sandwiched between two outer plates, and the high damping rubber is combined with the intermediate plate and the outer plate. The high damping rubber is adhered to each other, and the high damping rubber may be provided with the convex portions as described above, and the covering rubber may be provided as described above. According to such a configuration, when the intermediate plate and the two outer plates are sheared and deformed, the moments acting on the intermediate plate from the high damping rubbers on both sides of the intermediate plate can cancel each other out.

Hereinafter, examples relating to the present invention will be described, but the present invention is not intended to be limited to those shown in such examples.

[Example 1]
High damping rubber compositions and coated rubber compositions having the compositions shown in Table 1 were prepared. The highly damped rubber composition was extruded into a sheet and then punched into a flat plate to obtain a plate of the highly damped rubber composition (thickness 8 mm × side 36 mm). The coated rubber composition was rolled into a sheet to prepare a sheet body (thickness 2 mm × width 6 mm) of the coated rubber composition. Further, the high damping rubber composition was rolled into a sheet and then cut to a predetermined size to obtain a strip body (thickness 2 mm × width 1 mm) of the high damping rubber composition. Both sides of the sheet body of the coated rubber composition are sandwiched between two strip bodies of the high damping rubber composition, which are wound around the outer periphery of the plate-shaped body of the high damping rubber composition, and the end structure as shown in FIG. A rubber composite having the above was obtained. In this rubber composite, the dimensions A and B in FIG. 2 are 1 mm each, the dimension C is 6 mm, and the protrusion length of the convex portion and the thickness of the covering rubber are 2 mm.

A rectangular flat steel plate having a thickness of 6 mm, a length of 44 mm, and a width of 44 mm was laminated on each of the front and back surfaces of the rubber complex via a vulcanization adhesive. This is heated to 150 ° C. while pressurizing in the laminating direction to vulcanize the composition constituting the rubber composite, and the rubber composite is vulcanized and bonded to two steel plates to obtain a vibration damping device. A test piece for evaluating damping characteristics as a model was prepared.

[Examples 2 and 3]
A test piece was obtained in the same manner as in Example 1 except that the thickness of the plate-like body of the high-damping rubber composition, the width of the sheet body of the coated rubber composition, and the width of the strip body of the high-damping rubber composition were changed. rice field. Table 2 shows dimensions A, B, and C of this rubber complex in FIG. Further, the protruding length of the convex portion and the thickness of the covering rubber were 2 mm.

[Comparative Example 1]
A plate-shaped body (thickness 8 mm) of the highly damped rubber composition and a sheet body (thickness 2 mm × width 8 mm) of the coated rubber composition were produced in the same manner as in Example 1. A sheet body of this coated rubber composition was wound around the outer periphery of the plate-like body of the highly damped rubber composition to prepare a rubber composite. Using this rubber complex and a steel plate, a test piece was obtained in the same manner as in Example 1. This test piece corresponds to the prior art. In this test piece, the outer peripheral surface of the high damping rubber did not have a convex portion, and the entire outer peripheral surface was covered with a coated rubber layer. In this rubber composite, it can be considered that the dimensions A and B in FIG. 2 are 0 mm and the dimension C is 8 mm, the protrusion length of the convex portion is 0 mm, and the thickness of the covering rubber is 2 mm.

[Reference Example 1]
A plate-shaped body (high-damping rubber body) having a high-damping rubber composition was produced in the same manner as in Example 1. The dimensions of this high damping rubber body were the same as the dimensions of the rubber complexes of the other examples and comparative examples. Using this plate-shaped body and the steel plate, a test body was obtained in the same manner as in Example 1. In this test piece, since there was no covering rubber layer, the entire outer peripheral surface of the high damping rubber was exposed. In this highly damped rubber body, it can be considered that the dimensions A and B in FIG. 2 are 4 mm and the dimension C is 0 mm, the protrusion length of the convex portion is 2 mm, and the thickness of the covering rubber is 0 mm. ..

〔Evaluation methods〕
<Operation of testing machine>
The outline of the evaluation method is shown in FIG. Two test bodies 213 for each example and each comparative example were prepared. In the test bodies 213 shown in FIGS. 8A to 8E, reference numeral 210 represents a rubber complex (however, in Reference Example 1, a high damping rubber body, the same applies hereinafter), and reference numerals 211 and 212 indicate steel plates, respectively. ing.

As shown in FIGS. 8B and 8C, the steel plates 212 of the two test bodies 213 were opposed to each other, and the two test bodies 213 were fixed to the central fixing jig 214 via the steel plate 212 with a bottle. Further, the left and right fixing jigs 215 were fixed to the steel plates 211 of the two test bodies 213 with bottles. The central fixing jig 214 was fixed to the upper fixing arm 221 of the uniaxial shear tester (not shown) with a bottle via a joint 216. Further, as shown in FIG. 8D, two left and right fixing jigs 215 were fixed to the movable plate 222 on the lower side of the testing machine with a bottle via a joint 217.

Next, from the state shown in FIG. 8D, the movable platen 222 is displaced so as to be pushed up in the direction of the fixed arm 221 as shown by the white arrow in FIG. As shown in FIG. 8E, the composite 210 is in a state of being distorted and deformed in a direction orthogonal to the stacking direction of the test body 213. Next, from this state, the movable board 222 is displaced so as to be pulled down in the direction opposite to the direction of the fixed arm 6 as shown by the white arrow in FIG. 8 (E), and the operation is returned to the state shown in FIG. 8 (D). Was done. These displacement operations are regarded as one cycle.

<Destruction durability evaluation>
In the fracture durability evaluation, a large deformation of 300% was repeatedly applied, and the number of cycles until the test piece 213 was destroyed was recorded. The ratio of the number of cycles of each Example and Reference Example 1 was determined based on the number of cycles in which the test piece of Comparative Example 1 was destroyed. A ratio of the number of cycles of 105 or more was regarded as a pass (◯), and a ratio of less than 105 was regarded as a fail (x). The results are shown in Table 2.

<Aged deterioration evaluation>
The above testing machine is operated on the test body 213 with a displacement amount of 100% for 3 cycles, and in the 3rd cycle, the displacement amount (mm) and the load (mm) of the rubber composite in the direction orthogonal to the stacking direction of the test body 213. A hysteresis loop H (see FIG. 9) showing a relationship with N) was obtained. Based on this hysteresis loop H, the equivalent shear elastic modulus (Geq) was calculated from the following equation (Equation 1). Further, the test body 213 was deteriorated by being placed in an environment of 80 ° C. for one week, and Geq was determined. The Geq change rate before and after deterioration was obtained, and the ratio of the Geq change rate of each Example and Reference Example 1 was obtained based on the Geq change rate of the test body of Comparative Example 1.
A Geq change rate ratio of 110 or less was regarded as acceptable (〇), and a Geq change rate ratio of more than 110 was regarded as rejected (×). The results are shown in Table 2.
Geq = Keq × (d / S) (Equation 1)
Keq (N / mm): Slope of the straight line L shown by the solid line of the thick line in FIG. 9 connecting the maximum displacement point and the minimum displacement point of the hysteresis loop H d: Thickness (mm) of the rubber composite 210 of the test piece 213.
S: Cross-sectional area (mm ² ) of the rubber complex 210 of the test body 213.

From the results in Table 2, improvement in fracture durability was observed in Examples 1 to 3, which are test examples of the vibration damping device disclosed here. Therefore, in the vibration damping device disclosed here, it can be seen that the fracture suppressing performance of the high damping rubber is improved when the vibration damping device is operated and large deformation is repeatedly generated. Further, in the above experiment, it was found that the larger the dimension A and the dimension B, the more the fracture suppressing performance tends to be improved. Further, the larger the dimension C, the less likely it was that deterioration over time occurred.

10 Vibration damping device 11 First plate 12 Second plate 13 Viscoelastic body 13a First convex portion 13b Second convex portion 13c Outer peripheral surface between the first convex portion and the second convex portion 14 Covered rubber

Claims (7)

1st plate and
A second plate facing one of the main surfaces of the first plate,
A high damping rubber arranged between the first plate and the second plate and adhered to the first plate and the second plate, and
The coated rubber that covers the outer peripheral surface of the high damping rubber and
Equipped with
The covering rubber is a vibration damping device arranged apart from the first plate and the second plate. The outer peripheral surface of the high damping rubber has a first convex portion at the end portion on the first plate side and a second convex portion at the end portion on the second plate side.
The vibration damping device according to claim 1, wherein the outer peripheral surface between the first convex portion and the second convex portion of the high damping rubber is covered with the coated rubber. The dimension of the first convex portion in the direction perpendicular to the main surface of the first plate and the dimension of the second convex portion in the direction perpendicular to the main surface of the second plate are 1.5 mm or more, respectively. can be,
The vibration damping device according to claim 2, wherein the coated rubber covers 50% or more of the dimension between the first plate and the second plate of the high damping rubber. The vibration damping device according to any one of claims 1 to 3, wherein the high damping rubber contains a diene rubber as a rubber component. The vibration damping device according to claim 4, wherein the diene rubber is at least one rubber selected from the group consisting of natural rubber, isoprene rubber, butadiene rubber, and styrene butadiene rubber. The vibration damping device according to any one of claims 1 to 5, wherein the coated rubber contains a butyl rubber as a rubber component. The vibration damping device according to claim 6, wherein the butyl rubber is at least one type of rubber selected from the group consisting of brominated butyl rubber and chlorinated halogenated butyl rubber.

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