Vibration-damping structures, interior parts and automobiles

Abstract

To provide a vibration control structure capable of making an occupied space smaller, an interior component, and an automobile.SOLUTION: A vibration control structure comprises: an elastic member that has a predetermined width and a thickness smaller than a width in a direction intersecting a plane including the direction of the width, and has a spiral shape that turns from one end on an inner side to the other end on an outer side along the plane; and a vibration control member joined to the other end of the elastic member. At least a part of the other end side of the elastic member is provided with a wedge-shaped part that satisfies Formula (1).SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a vibration damping structure, an interior part, and an automobile. [Background technology]

[0002] Vibration-damping structures for suppressing vibrations are used, for example, in automobiles, etc. Various configurations have been proposed for vibration-damping structures, and for example, Patent Document 1 and Non-Patent Document 1 describe vibration-damping structures that use acoustic black hole structures. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2010-144868 [Non-patent literature]

[0004] [Non-Patent Document 1] S.Park, JYLee, W.Jeon, Vibration damping of thin structures using surface-attached spiral acoustic black holes, In Inter-noise 2020, 2020 Summary of the Invention [Problem to be solved by the invention]

[0005] It is desirable to reduce the space occupied by such a vibration-damping structure, which would allow the vibration-damping structure to be installed in a wider variety of locations. Therefore, an object of the present invention is to provide a vibration-damping structure, an interior part, and an automobile that can reduce the space occupied. [Means for solving the problem]

[0006] The vibration-damping structure of the present invention comprises an elastic member having a predetermined width and a thickness smaller than the width in a direction intersecting a plane containing the width direction, and having a spiral shape that spirals along the plane from one inner end to the other outer end, and a vibration-damping member joined to the other end of the elastic member, and at least a portion of the other end of the elastic member is provided with a wedge-shaped portion that satisfies the following formula (1).

[0007]

number

[0008] According to the present invention, the elastic member has a spiral shape along a plane including the width direction, so that the size of one side of the plane and the size in the thickness direction can be reduced while maintaining the vibration damping effect, thereby making it possible to further reduce the occupied space. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a perspective view schematically illustrating the configuration of a vibration damping structure according to one embodiment of the present invention. [Figure 2] 2 is a plan view showing an example of the configuration of an elastic member shown in FIG. 1. FIG. [Figure 3] 3 is a diagram showing an example of a cross-sectional configuration taken along the center line shown in FIG. 2. FIG. [Figure 4] 2(A), 2(B), 2(C), and 2(D) are cross-sectional views schematically showing an example of a joint between an elastic member and a member to be damped shown in FIG. 1. [Figure 5] 1A is a diagram schematically showing an example of the positions of antinodes and nodes of a primary vibration mode of a damped member, and FIG. 1B is a diagram schematically showing an example of the positions of antinodes and nodes of a secondary vibration mode of a damped member. [Figure 6] FIG. 10 is a perspective view showing the configuration of an elastic member according to a comparative example. [Figure 7] FIG. 1 is a block diagram showing the configuration of a measurement system for measuring a transfer function. [Figure 8]FIG. 1 is a block diagram showing the configuration of a measurement system for measuring vibration damping time. [Figure 9] FIG. 1A is a diagram showing the transfer functions measured in Example 1 and Comparative Example 1, and FIG. 1B is an enlarged view of a portion of FIG. [Figure 10] FIG. 1A is a graph showing the vibration damping time measured in a reference example, FIG. 1B is a graph showing the vibration damping time measured in comparative example 1, and FIG. 1C is a graph showing the vibration damping time measured in example 1. [Figure 11] FIG. 10 is a diagram showing transfer functions measured in Examples 2 and 3. [Figure 12] 1A is a graph showing the vibration damping time measured in Example 2, and FIG. 1B is a graph showing the vibration damping time measured in Example 3. [Figure 13] FIG. 1 is a diagram showing transfer functions measured in Examples 1, 4, and 5. [Figure 14] 1A is a graph showing the vibration damping time measured in Example 4, and FIG. 1B is a graph showing the vibration damping time measured in Example 5. [Figure 15] FIG. 1 is a diagram showing transfer functions measured in Examples 1 and 6. [Figure 16] 1A is a graph showing the vibration damping time measured in Example 1, and FIG. 1B is a graph showing the vibration damping time measured in Example 6. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, embodiments of the present invention will be described with reference to the drawings, but the technical scope of the present invention is not limited to the following embodiments. Note that the dimensional ratios in the drawings are exaggerated for the sake of explanation and may differ from the actual ratios. In this specification, the range "a to b" means "a or more and b or less." Furthermore, unless otherwise specified, operations and measurements of physical properties, etc. are performed under conditions of room temperature (20 to 25°C) and relative humidity of 40 to 50%.

[0011] [Configuration of vibration control structure] FIG. 1 shows the configuration of a vibration-damping structure 10 according to one embodiment of the present invention, together with a member to be damped 20. The vibration-damping structure 10 includes a plate-shaped elastic member 11 and a vibration-damping member 12 joined to the elastic member 11, with at least a portion of the elastic member 11 joined to the member to be damped 20. The vibration-damping structure 10 joined to the member to be damped 20 damps vibrations of the member to be damped 20. In the following description, the thickness direction of the plate-shaped elastic member 11 is sometimes referred to as the Z direction, and the directions intersecting this are sometimes referred to as the X direction and the Y direction. The size of the vibration-damping structure 10 in the X direction and the Y direction are approximately the same, and the vibration-damping structure 10 has a side dimension D in the XY plane.

[0012] (elastic member) FIG. 2 shows the planar configuration (XY plane) of elastic member 11, and FIG. 3 shows the cross-sectional configuration of elastic member 11 taken along center line Wc shown in FIG. 2. Elastic member 11 may be made of any elastic material, but is preferably made of a metal material such as iron or steel from the standpoint of ease of handling. Elastic member 11 is a ribbon-shaped plate-like member having a predetermined width w, length l, and thickness h. For example, the plane including the direction of width w and the direction of length l corresponds to the XY plane, and the direction of thickness h corresponds to the Z direction.

[0013] The width w is, for example, 1 mm to 100 mm. In order to reduce the size D (FIG. 1) of one side while maintaining the vibration damping effect of the vibration damping structure 10, it is preferably 10 mm to 30 mm, and more preferably 15 mm to 20 mm.

[0014] The length l is sufficiently larger than the width w, for example, 50 mm to 2000 mm. The elastic member 11 has one end e1 and the other end e2 in the direction of the length l. The elastic member 11 has, for example, the same width w from the one end e1 to the other end e2, but the width w may vary from the one end e1 to the other end e2. For example, the one end e1 side of the elastic member 11 is joined to the vibration-damped member 20, and the other end e2 side is joined to the vibration-damping member 12.

[0015] The elastic member 11 has a spiral shape that is wound along the XY plane from one end e1 to the other end e2. In other words, the elastic member 11 has a spiral shape that is wound from the inner end e1 to the outer end e2 along a plane including the direction of the width w. In this embodiment, the elastic member 11 has a spiral shape that is wound along the XY plane. As will be described in detail later, this reduces the size D of one side in the XY plane and the size in the Z direction while maintaining the vibration damping effect, thereby making it possible to reduce the occupied space. The elastic member 11 is wound, for example, regularly, but the winding may also be irregular. The elastic member 11 has a thick portion 11C on the one end e1 side and a wedge-shaped portion 11W on the other end e2 side.

[0016] The thick portion 11C has a thickness hc (FIG. 3). The thickness hc is smaller than the width w, and is, for example, 0.5 mm to 50 mm. To limit the size of the vibration damping structure 10 in the Z direction, the thickness hc is preferably 10 mm or less, and more preferably 5 mm or less. This thick portion 11C is provided with a joint 11J that is joined to the member to be damped 20. The joint 11J is joined to the member to be damped 20 by, for example, mechanical bonding, magnetic bonding, or chemical bonding.

[0017] 4(A) to 4(D) show an example of the cross-sectional configuration of the joint 11J and the vibration-damped member 20. The joint 11J and the vibration-damped member 20 are joined mechanically, for example, using a bolt 31B and a nut 31N (FIG. 4(A)). The joint 11J and the vibration-damped member 20 are joined magnetically, for example, using a magnet 32 such as a neodymium magnet (FIG. 4(B)). Alternatively, the joint 11J and the vibration-damped member 20 are joined chemically, for example, using double-sided tape 33 or adhesive 34 (FIGS. 4(C) and 4(D)). The joint 11J and the vibration-damped member 20 may also be joined by welding, soldering, or the like. It is preferable that the joint 11J be in direct contact with the vibration-damped member 20. This facilitates transmission of vibrations from the vibration-damped member 20 to the joint 11J, thereby making it easier for the vibrations to be attenuated. For example, in the case of a mechanical joint using a bolt 31B and a nut 31N, the joint portion 11J and the member to be damped 20 come into direct contact with each other.

[0018] Wedge-shaped portion 11W is provided adjacent to thick portion 11C, for example, and extends from position eW between one end e1 and the other end e2 to the other end e2. Wedge-shaped portion 11W has a thickness h that gradually decreases from position eW toward the other end e2. That is, thickness h of wedge-shaped portion 11W is greatest at position eW and smallest at the other end e2. Thickness h of wedge-shaped portion 11W satisfies the following formula (1):

[0019]

number

[0020] The arbitrary position on the other end e2 side, which is the measurement starting point of the distance x in the above formula (1), is an arbitrary position closer to the other end e2 than the one end e1, for example, the other end e2. The distance x is measured, for example, at the center in the direction of the width w of the elastic member 11, i.e., along the center line Wc. Furthermore, y corresponds to the thickness of the elastic member 11 at the measurement starting point of the distance x (for example, the other end e2), and is, for example, 0.01 to 1 mm. To suppress reflection of vibration waves, y is preferably 0.5 mm or less.

[0021] By providing such a wedge-shaped portion 11W on the other end e2 side of the elastic member 11, a so-called acoustic black hole structure is realized. This suppresses reflection of vibration waves at the other end e2 of the elastic member 11, thereby effectively attenuating vibration. At least a portion of the wedge-shaped portion 11W needs to be located closer to the other end e2 than to the one end e1, in other words, closer to the other end e2 than to the center between the one end e1 and the other end e2.

[0022] The frequency threshold f at which vibration can be damped by the wedge-shaped portion 11W cut-on can be calculated using, for example, the following equation (2).

[0023]

number

[0024] In the wedge-shaped portion 11W, the threshold value f cut-on It is possible to attenuate vibrations of frequencies above this level. That is, by increasing the length L (FIG. 3) of the wedge-shaped portion 11W, the vibration-damping structure 10 can effectively attenuate vibrations of lower frequencies. The length L of the wedge-shaped portion 11W is, for example, the distance measured from the other end e2 to a position eW along the spiral shape (along the center line Wc). For example, if the wedge-shaped portion 11W (elastic member 11) is made of iron and the thickness h at the position eW is 4.0 mm, the threshold value f is reached when the length L is 500 mm. cut-on When the frequency is 22.6 Hz and the length L is 100 mm, the threshold f cut-on When the frequency is 565Hz and the length L is 50mm, the threshold f cut-onis 2260 Hz. It is preferable that the wedge-shaped portion 11W can damp vibrations with frequencies of 300 Hz or less. This makes it possible to realize a vibration-damping structure 10 that can effectively damp vibrations in the low-frequency band. The length L of the wedge-shaped portion 11W is preferably 90% or more of the length l of the elastic member 11, and more preferably 95% or more. By increasing the proportion of the wedge-shaped portion 11W in the elastic member 11, vibrations can be damped more effectively.

[0025] (Vibration-damping member) The vibration-damping member 12 joined to the other end e2 of the elastic member 11 serves to convert the vibration energy collected at the other end e2 by the acoustic black hole structure into thermal energy and thereby attenuate the vibration. The vibration-damping member 12 is made of, for example, a plate-shaped viscoelastic material. The thickness of this plate-shaped vibration-damping member 12 is preferably greater than the thickness of the other end e2 of the elastic member 11. The viscoelastic material constituting the vibration-damping member 12 is preferably a polymer material such as rubber. The specific gravity of the vibration-damping member 12 is preferably equal to or greater than that of the elastic member 11. Such a vibration-damping member 12 can efficiently attenuate the vibration energy collected at the other end e2.

[0026] The length D of one side in the XY plane of the vibration damping structure 10 including the elastic member 11 and the vibration damping member 12 is, for example, 30 mm or more and 500 mm or less. In order to reduce the occupied space while maintaining the effect of damping low-frequency vibrations, it is preferably 40 mm or more and 150 mm or less.

[0027] [Configuration of the vibration-damped member] A vibration-damping structure 10 having such elastic members 11 and vibration-damping members 12 is provided, for example, on the surface S of a plate-shaped member to be damped 20 (FIG. 1). The surface S of this member to be damped 20 is provided, for example, along the XY plane. In other words, a spiral shape of the elastic members 11 is formed along the surface S of the member to be damped 20. The member to be damped 20 is made of, for example, a thin metal plate. By providing the vibration-damping structure 10 on a member to be damped 20 with a smaller vibration-damping effect (damping coefficient), the vibration of the member to be damped 20 can be more effectively damped.

[0028] The vibration-damped member 20 has, for example, a fixed portion (not shown) that is fixed to another member, and the joint portion 11J of the elastic member 11 is joined to a portion of the vibration-damped member 20 other than the fixed portion. It is preferable that the joint portion 11J of the elastic member 11 is joined to the position of the antinode of the vibration mode of the vibration-damped member 20 of the second or lower order, i.e., a position where low-frequency vibration is larger. This makes it possible to more effectively damp low-frequency vibration.

[0029] Figure 5(A) shows a schematic representation of the primary vibration mode of the member to be damped 20, and Figure 5(B) shows a schematic representation of the secondary vibration mode, using vibration analysis. Position a in Figures 5(A) and 5(B) represents the antinode of each vibration mode, and position n represents the node of each vibration mode. For example, by joining joint 11J of elastic member 11 to position a of member to be damped 20, low-frequency vibrations can be damped more effectively than when joined to position n.

[0030] [Effects of vibration control structure] In the vibration damping structure 10 according to this embodiment, the elastic member 11 has a spiral shape along the XY plane, so that the size D of one side in the XY plane and the size in the Z direction are reduced while maintaining the vibration damping effect. This makes it possible to further reduce the occupied space. This effect will be described in detail below.

[0031] For example, if the elastic member has a linear shape, the length of the elastic member is the same as the length of one side of the XY plane. Therefore, in order to install this elastic member, it is necessary to secure a space in the XY plane equal to the length of the elastic member, which reduces the degree of freedom in terms of installation location. In particular, for elastic members intended to damp vibrations in a frequency band of 300 Hz or less (e.g., 50 Hz to 300 Hz or 100 Hz to 300 Hz), the size of one side of the XY plane becomes larger, which reduces the degree of freedom in terms of installation location.

[0032] 6 shows the configuration of an elastic member 111 according to a comparative example. This elastic member 111 has a spiral shape, so the size of one side in the XY plane can be made smaller than that of a linear elastic member. However, because the spiral shape of this elastic member 111 rotates in the thickness direction (Z direction) of the elastic member, the size in the Z direction is larger than that of a linear elastic member. Therefore, it is difficult to install the elastic member 111 in a location where the size in the Z direction is limited.

[0033] In contrast, in the vibration damping structure 10, the elastic member 11 has a spiral shape along the XY plane, so the size D of one side in the XY plane is sufficiently smaller than the length l, and the size in the Z direction is approximately the same as the thickness of the elastic member 11 or the vibration damping member 12. That is, the size D of one side in the XY plane is smaller than that of a linear elastic member, and the size in the Z direction is smaller than that of the spiral-shaped elastic member 111. Furthermore, the elastic member 11 maintains the same vibration damping effect as a linear elastic member and a spiral-shaped elastic member 111 that have approximately the same length and thickness.

[0034] In this way, with the vibration damping structure 10 of this embodiment, the size D of one side in the XY plane and the size in the Z direction are reduced while maintaining the vibration damping effect, which makes it possible to further reduce the space it occupies.

[0035] <Application example> The vibration-damping structure 10 described in the above embodiment can be suitably used for damping various vibrations. In particular, the vibration-damping structure 10 can be configured very compactly. Because of its compact configuration, the vibration-damping structure 10 is preferably mounted on a vehicle for use. Examples of application areas include dash insulators, dash panels, floor carpets, spacers, door trims, sound-absorbing structures in door trims, sound-absorbing structures in compartments, instrument panels, instrument center boxes, instrument upper boxes, air conditioner housings, roof trims, sound-absorbing structures in roof trims, sun visors, rear seat air conditioning ducts, cooling ducts for battery cooling systems in battery-powered vehicles, cooling fans, center console trims, sound-absorbing structures in consoles, parcel trims, parcel panels, seat headrests, front seat backs, and rear seat backs. Furthermore, in the trunk, the vibration-damping structure 10 can be applied to trunk floor trims, trunk boards, trunk side trims, sound-absorbing structures in trims, and drafter covers. It can also be applied to the interior of a vehicle or between panels, such as pillar trim or fenders. It is particularly suitable for use in automotive interior parts, as it has excellent vibration damping in the frequency range of 300 Hz or less, is lightweight, and allows for a thin overall thickness. [Example]

[0036] The present invention will be described in more detail below with reference to examples, although the technical scope of the present invention is not limited to the following examples.

[0037] <<Transfer function measurement>> The transfer function was measured using a measurement system 200 shown in Figure 7. The measurement system 200 includes an impulse hammer 210 (Model 086C03, hard chip, manufactured by PCB Piezotronics, Inc.), an acceleration sensor 220 (Model 356A01, manufactured by PCB Piezotronics, Inc.), an FFT (Fast Fourier Transform) analyzer 230 (SCADADSIII, manufactured by Siemens AG), and a PC (Personal Computer) 240. The impulse hammer 210 and acceleration sensor 220 are connected to the FFT analyzer 230, which is communicatively connected to the PC 240. A damping structure and acceleration sensor 220 are attached to one side of a damped member, and the other side of the damped member, which is suspended by a rubber cord, is struck with the impulse hammer 210. The detection results of the acceleration sensor 220 and impulse hammer at this time are input into the FFT analyzer 230, and the transfer function is calculated. The measurement frequency range was 0 Hz to 10,240 Hz, and Δf = 2.5 Hz. The member to be damped was supported freely.

[0038] <<Measurement of vibration decay time>> The vibration damping time was measured using a measurement system 300 shown in Figure 8. The measurement system 300 includes an impulse hammer 310 (Model 086C03, hard chip, manufactured by PCB Piezotronics, Inc.), an acceleration sensor 320 (Model 356A01, manufactured by PCB Piezotronics, Inc.), an ICP-USB conversion module 330 (Model 485B39, manufactured by The Modal Shop, Inc.), and a PC (personal computer) 340. The impulse hammer 310 and acceleration sensor 320 are connected to the ICP-USB conversion module 330, which is communicatively connected to the PC 340. The ICP-USB conversion module 330 is a device that supplies a constant current to the impulse hammer 310 and acceleration sensor 320 and converts a USB signal into a digital output signal. A vibration control structure and acceleration sensor 320 were attached to one side of the damped member, and the other side of the damped member, which was suspended by a rubber cord, was struck with an impulse hammer 310. The acceleration response to the excitation force of the impulse hammer 310 at this time was input to a PC 340 using the acceleration sensor 320 and an ICP-USB conversion module 330, and the vibration damping time was calculated. Graphs of the vibration damping time (see Figures 10, 12, 14, and 16, described below) were created by dividing the time domain of the acceleration by the maximum acceleration and normalizing it. The damped member was supported freely.

[0039] (Confirmation of vibration control effect) [Example 1] Elastic members having the following conditions were prepared: Material: General structural rolled steel (SS400) Volume: 20626.38mm 3 Joint thickness: 4.5mm Maximum thickness of wedge: 4.0 mm Minimum thickness of wedge: 0.2 mm Width: 18mm Inner length of spiral: 500mm Thickness of the wedge: Equation (3).

[0040]

number

[0041] The vibration damping members were prepared under the following conditions: Material: Rubber Dimensions: length along the spiral 55mm, width 18mm, thickness 1mm.

[0042] The vibration damping member was joined to the other end of the elastic member, thereby obtaining the vibration damping structure of Example 1.

[0043] The vibration damping structure obtained above was joined to a member to be damped under the following conditions using bolts and nuts, and then the transfer function and vibration damping time were measured: Material: Cold-rolled steel plate (SPCC) Dimensions: 300mm long, 200mm wide, 1.6mm thick.

[0044] [Comparative Example 1] The transfer function and vibration damping time were measured in the same manner as in Example 1 above, except that an elastic member with the following conditions was used. The elastic member used in Comparative Example 1 did not have a wedge-shaped portion. Other than this, the conditions for this elastic member were almost the same as those for the elastic member used in Example 1: Material: General structural rolled steel (SS400) Volume: 20662.98mm 3 Joint thickness: 2.2mm Thickness excluding joints: 1.7 mm Wedge: None Width: 18mm Inner length of the spiral: 500mm.

[0045] [Reference example] The transfer function and vibration damping time were measured in the same manner as in Example 1 above, except that the vibration damping structure was not joined to the member to be damped.

[0046] The transfer function results measured for Example 1, Comparative Example 1, and Reference Example are shown in Figure 9, and the vibration damping time results are shown in Figure 10. Figure 9(B) shows an enlarged view of the 500 Hz to 1200 Hz frequency range of Figure 9(A). Figure 10(A) shows the vibration damping time results measured for Reference Example, Figure 10(B) shows the vibration damping time results measured for Comparative Example 1, and Figure 10(C) shows the vibration damping time results measured for Example 1. The peaks of the transfer functions for Example 1 and Comparative Example 1 are smaller than the peak of the transfer function for the Reference Example, indicating that the vibration of the damped member is damped in Example 1 and Comparative Example 1. The magnitude of this vibration reduction is greater in Example 1 than in Comparative Example 1. Furthermore, the peak of normalized acceleration (acceleration / maximum acceleration) over a short period of time is smaller in Example 1 than in the Reference Example and Comparative Example 1. Therefore, it was found that the vibration damping structure of Example 1 has a higher vibration damping effect than the vibration damping structure of Comparative Example 1.

[0047] [Example 2] The transfer function and vibration damping time were measured in the same manner as in Example 1, except that the joint of the elastic member was joined to the position of the antinode of the vibration mode of the second or lower order of the member to be damped.

[0048] [Example 3] The transfer function and vibration damping time were measured in the same manner as in Example 1 above, except that the joints of the elastic members were joined to the node positions of the vibration modes of the second or lower order of the member to be damped.

[0049] FIG. 11 shows the transfer function results measured in Examples 2 and 3 and the Reference Example, and FIG. 12 shows the vibration damping time results. FIG. 11 shows an enlarged view of the 500 Hz to 1200 Hz portion of the measured frequency band. FIG. 12(A) shows the vibration damping time results measured in Example 2, and FIG. 12(B) shows the vibration damping time results measured in Example 3. The peaks of the transfer function in Examples 2 and 3 are smaller than the peak of the Reference Example, indicating that the vibration of the damped member is damped in Examples 2 and 3 (FIG. 11). The magnitude of this vibration reduction is greater in Example 2 than in Example 3. Furthermore, Example 2 has a smaller peak in the acceleration (acceleration / maximum acceleration) normalized over a short period of time than Example 3 (FIGS. 12(A) and 12(B)). Therefore, it was found that the vibration of the damped member can be more effectively damped by joining the damping structure to the antinode position of the vibration mode of the damped member that is lower than the second order or lower.

[0050] [Example 4] The transfer function and vibration damping time were measured in the same manner as in Example 1 above, except that the joint portion of the elastic member was joined to the member to be damped using double-sided tape.

[0051] [Example 5] The transfer function and vibration damping time were measured in the same manner as in Example 1 above, except that the joint portion of the elastic member was joined to the member to be damped using an adhesive.

[0052] The transfer function results measured in Examples 1, 4, and 5 are shown in Figure 13, and the vibration damping time results are shown in Figure 14. Figure 13 shows an enlarged view of the 500 Hz to 1200 Hz portion of the measurement frequency band. Figure 14(A) shows the vibration damping time results measured in Example 4, and Figure 14(B) shows the vibration damping time results measured in Example 5. Many of the peaks of the transfer function in Example 1 were smaller than those of Examples 4 and 5, but no significant differences were observed. Furthermore, no significant differences were observed in the peaks of the vibration damping time in Examples 1, 4, and 5. Therefore, it was found that when double-sided tape and adhesive were used to join the elastic member and the vibration-damped member, the vibration of the joined vibration-damped member was damped to the same extent as when bolts and nuts were used.

[0053] [Example 6] The transfer function and vibration damping time were measured in the same manner as in Example 1, except that the joint portion of the elastic member was joined to the member to be damped using a neodymium magnet.

[0054] The transfer function results measured in Examples 1 and 6 are shown in Figure 15, and the vibration damping time results in Figure 16. Figure 15 shows an enlarged view of the 500 Hz to 1200 Hz portion of the measurement frequency band. Figure 16(A) shows the vibration damping time results measured in Example 1, and Figure 16(B) shows the vibration damping time results measured in Example 6. No significant differences were observed in the peaks of the transfer function and vibration damping time between Examples 1 and 6. Therefore, it was found that when a neodymium magnet is used to join the elastic member and the vibration-damped member, the vibration of the joined vibration-damped member is damped to the same extent as when a bolt and nut are used.

[0055] The vibration-damping structure of the present invention has been described above using embodiments and examples. However, those skilled in the art can make appropriate additions, modifications, and omissions to the present invention within the scope of the technical concept. For example, the configurations, shapes, sizes, etc. of the components of the vibration-damping structure described in the above embodiments and examples are merely examples, and other configurations, shapes, sizes, etc. may be used.

[0056] For example, in the above embodiment, the wedge-shaped portion 11W is provided from the position eW to the other end e2. However, the wedge-shaped portion 11W does not have to include the other end e2. For example, the thickness of the wedge-shaped portion 11W may be constant in a portion on the other end e2 side. Furthermore, the position eW does not have to be located near the center of the spiral shape, as long as it is located inside the other end e2.

[0057] In the above embodiment, an example in which the vibration-damping structure is attached to a plate-shaped member to be damped has been described, but the member to be damped may have another shape, such as a rod shape. For example, the vibration-damping structure may be attached between two opposing rod-shaped members. [Explanation of symbols]

[0058] 10 Vibration control structure 11 Elastic member 11C Thick part 11J joint 11W Wedge-shaped part 12 Vibration-damping member 20 Damped member e1 one end e2 other end eW position x distance w width D Size of one side l, L length.

Claims

1. an elastic member having a predetermined width and a thickness smaller than the width in a direction intersecting a plane including the width direction, and having a spiral shape that spirals along the plane from one inner end to the other outer end; a vibration-damping member joined to the other end of the elastic member, At least a part of the other end of the elastic member is provided with a wedge-shaped portion that satisfies the following formula (1): The wedge-shaped portion has a thickness that gradually decreases from the one end toward the other end. [Equation 1]

2. The vibration damping structure according to claim 1 , wherein the flat surface is disposed along a surface of a member to be damped.

3. 3. The vibration damping structure according to claim 1, wherein the vibration damping structure is joined to a position of an antinode of a vibration mode of a second or lower order of the member to be damped.

4. 4. The vibration-damping structure according to claim 1, wherein the vibration-damping member includes a viscoelastic material.

5. 5. The vibration damping structure according to claim 1, wherein the elastic member includes a metal material.

6. An interior part for an automobile, comprising the vibration damping structure according to any one of claims 1 to 5.

7. An automobile having the vibration damping structure according to any one of claims 1 to 5 or the interior part according to claim 6.

Images