Cylindrical anti-vibration device for motor mount

Abstract

The present invention provides a cylindrical anti-vibration device for a motor mount having a novel structure and capable of improving anti-vibration performance against high-frequency vibration which is a problem in the motor mount. An inner shaft member (12) and an outer cylinder member (14) are connected through a main body rubber elastic body (16), and the main body rubber elastic body (16) is provided with a plurality of rubber legs (20) which extend from the inner shaft member (12) to the outer cylinder member (14) and connect the inner shaft member (12) and the outer cylinder member (14) with each other. The rubber leg (20) is provided with a plurality of vibration-damping protrusions (30, 32) which protrude on the surface and are located at an intermediate portion separated from either the inner shaft member (12) or the outer cylinder member (14) in the connection direction, and the plurality of vibration-damping protrusions (30, 32) are arranged in parallel and spaced apart from each other in the connection direction of the rubber leg (20).

Description

Technical Field

[0001] The present invention relates to a cylindrical vibration isolating device for a motor mount for vibration-isolating and supporting a driving electric motor in an environmentally friendly vehicle such as an electric vehicle. Background Art

[0002] In recent years, against the backdrop of increasing concern about environmental issues, etc., eco-friendly cars using electric motors have been proposed in place of internal combustion engines as a driving source.

[0003] However, since the required characteristics of a vibration-proof device for a motor mount for vibration-proofing a power unit including an electric motor are greatly different from those of a vibration-proof device for an engine mount for vibration-proofing an existing internal combustion engine, the development of a vibration-proof device that is more suitable for a motor mount is being promoted. For example, the applicant proposed a cylindrical vibration-proof device for a motor mount having a response structure for high-frequency vibrations that are a problem in a motor mount in International Publication No. 2020 / 175640 (Patent Document 1).

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: International Publication No. 2020 / 175640 Summary of the invention

[0007] Problems to be solved by the invention

[0008] However, the development of the cylindrical vibration isolating device for the motor mount is in progress, and there is room for further improvement, especially in terms of dealing with high-frequency vibrations (for example, high dynamic springs caused by rubber surge).

[0009] The problem to be solved by the present invention is to provide a cylindrical vibration isolating device for a motor mount having a novel structure, which can improve the vibration isolating performance against high-frequency vibrations that are a problem in motor mounts.

[0010] Means used to solve problems

[0011] The following describes the preferred modes for understanding the present invention. The modes described below are exemplary and can be used in combination with each other as appropriate. The multiple components described in each mode can be identified and used as independently as possible, and can be used in combination with any component described in other modes as appropriate. Therefore, the present invention is not limited to the modes described below, and various other modes can be realized.

[0012] The first mode is a cylindrical vibration isolating device for a motor mount, in which an inner shaft member and an outer cylinder member are connected by a main rubber elastic body, wherein the main rubber elastic body has a plurality of rubber feet extending from the inner shaft member toward the outer cylinder member to connect the inner shaft member and the outer cylinder member to each other, and the rubber feet are provided with a plurality of vibration-damping protrusions protruding on the surface at an intermediate portion separated from either the inner shaft member or the outer cylinder member in the connection direction, and the plurality of vibration-damping protrusions are spaced from each other and arranged in parallel in the connection direction of the rubber feet.

[0013] According to the cylindrical vibration isolation device for a motor mount formed in accordance with the structure of this method, the peak of the high dynamic spring caused by the surge of the rubber foot is reduced by the resonance effect of the vibration-damping protrusion (based on the vibration-damping effect of the dynamic vibration damper), thereby achieving improvement in quietness in the high-frequency range.

[0014] In addition, for example, if the natural vibration frequencies of the plurality of vibration-damping protrusions provided on the rubber foot are set to be the same, the vibration-damping effect against the surge of the rubber foot can be advantageously obtained at a specific frequency. In addition, for example, if different natural vibration frequencies are set for the plurality of vibration-damping protrusions provided on the rubber foot, the vibration-damping effect against the surge of the rubber foot can be effectively obtained over a wider frequency range.

[0015] The plurality of vibration-damping protrusions are arranged in parallel and spaced apart from each other in the connection direction of the rubber foot, so that the degree of freedom in designing the size and shape of each vibration-damping protrusion can be greatly ensured, and the intended vibration-damping effect can be obtained more efficiently. In addition, for example, by arranging the vibration-damping protrusions at the portions of the rubber foot where the amplitude of the bending deformation becomes large, the vibration-damping effect of the vibration-damping protrusions can be efficiently obtained not only for the rubber surge of the first-order vibration mode, but also for the rubber surge of the second-order or higher-order vibration modes.

[0016] A second aspect is the cylindrical vibration isolating device for a motor mount according to the first aspect, wherein a plurality of different natural frequencies are set in the plurality of vibration-damping protrusions provided on the rubber leg.

[0017] According to the cylindrical vibration isolating device for a motor mount configured according to this embodiment, a vibration reduction effect can be obtained in a wide frequency range by a plurality of vibration reduction protrusions having different natural frequencies in response to the high dynamic spring caused by surge of the rubber foot.

[0018] A third aspect is the cylindrical vibration isolating device for a motor mount according to the second aspect, wherein the plurality of different natural frequencies are set by making the projection dimensions of the vibration-damping protrusions from the rubber legs different.

[0019] According to the cylindrical vibration isolating device for a motor mount configured according to this embodiment, since the projection dimensions of the plurality of vibration-damping protrusions from the rubber feet are different from each other, it is possible to easily set different natural vibration frequencies for the plurality of vibration-damping protrusions.

[0020] A fourth aspect is the cylindrical vibration isolating device for a motor mount according to the second aspect or the third aspect, wherein the plurality of different natural frequencies are set by making the thickness dimension in the radial direction of the vibration-damping protrusion different.

[0021] According to the cylindrical vibration isolating device for a motor mount configured according to this embodiment, different natural frequencies can be easily set for the plurality of vibration-damping protrusions by making the thickness dimensions in the radial direction different among the plurality of vibration-damping protrusions.

[0022] A fifth aspect is the cylindrical vibration isolating device for a motor mount according to any one of the first to fourth aspects, wherein the plurality of vibration-damping protrusions are arranged substantially evenly with respect to the rubber leg in a connecting direction of the rubber leg.

[0023] According to the cylindrical vibration isolating device for a motor mount having a structure according to this embodiment, by arranging a plurality of vibration-damping protrusions substantially evenly in the radial direction, it is possible to ensure the spacing distance between the vibration-damping protrusions, and it is easy to set the radial thickness dimension of each vibration-damping protrusion with a large degree of freedom. In addition, it is easy to arrange a plurality of vibration-damping protrusions at a portion where the amplitude of the bending deformation of the rubber foot becomes large in surge of a multi-order vibration mode, and it is possible to obtain a vibration-damping effect effective for surge of the second order or higher.

[0024] A sixth aspect is a cylindrical vibration isolating device for a motor mount according to any one of the first to fifth aspects, wherein a distance between the vibration-damping protrusions arranged adjacent to each other in a connecting direction of the rubber foot is shorter than either a distance from the innermost vibration-damping protrusion to the inner peripheral end of the rubber foot or a distance from another vibration-damping protrusion located at the outermost periphery to the outer peripheral end of the rubber foot.

[0025] According to the cylindrical vibration isolating device for a motor mount having a structure according to this embodiment, since the plurality of vibration-damping protrusions are arranged at positions close to each other in the connection direction of the rubber foot, it is possible to obtain an excellent vibration-damping effect based on the cooperation of the plurality of vibration-damping protrusions for surge in the first-order vibration mode of the rubber foot. In addition, by the plurality of vibration-damping protrusions arranged spaced apart from each other in the connection direction of the rubber foot, it is possible to efficiently obtain a vibration-damping effect for surge in multiple-order vibration modes.

[0026] The seventh method is a cylindrical vibration isolation device for a motor mount, in which an inner shaft component and an outer cylinder component are connected by a main rubber elastic body, wherein the main rubber elastic body has a plurality of rubber feet extending from the inner shaft component toward the outer cylinder component to connect these inner shaft components and outer cylinder components to each other, and a vibration-damping protrusion is provided between the circumferential spaces between the circumferentially adjacent rubber feet to connect these rubber feet to each other in the circumferential direction, and in the vibration-damping protrusion, the axial dimension is larger than the circumferential dimension at the portion located between the circumferential spaces between the rubber feet.

[0027] According to the cylindrical vibration isolating device for a motor mount having a structure according to this embodiment, the vibration-damping protrusion is provided between the rubber feet in the circumferential direction, and both ends of the vibration-damping protrusion in the circumferential direction are supported by the rubber feet, so that it is easy to set the resonance frequency of the vibration-damping protrusion to a higher frequency. In addition, since the axial dimension of the vibration-damping protrusion between the rubber feet in the circumferential direction is larger than the circumferential dimension, it is easy to set the mass of the vibration-damping protrusion to be large and obtain a large vibration-damping effect, and it is easy to ensure the degree of freedom of adjustment of the resonance frequency of the vibration-damping protrusion and to set it to the high frequency side.

[0028] An eighth aspect is the cylindrical vibration isolating device for a motor mount according to the seventh aspect, wherein both axial end portions of the vibration-damping protrusion do not protrude axially outward relative to the axial end surface of the rubber foot.

[0029] According to the cylindrical vibration isolating device for a motor mount having the structure according to this embodiment, by providing the vibration-damping protrusions using the circumferential space between the rubber feet, it is possible to prevent the size of the rubber feet in the axial direction from increasing while effectively achieving the vibration-damping effect on the surge of the rubber feet.

[0030] The ninth method is a cylindrical vibration isolation device for a motor mount, in which an inner shaft member and an outer tube member are connected by a main rubber elastic body, wherein the main rubber elastic body has a plurality of rubber feet extending from the inner shaft member toward the outer tube member to connect these inner shaft members and outer tube members to each other, and a vibration-damping protrusion protruding on the surface is provided on the rubber foot, and the vibration-damping protrusion extends along the connection direction of the rubber foot.

[0031] According to the cylindrical vibration isolating device for a motor mount having a structure according to this embodiment, even when the antinode portion in the vibration mode of the surge of the rubber foot is offset from the center or located at multiple locations in the connection direction of the rubber foot, it is easy to provide the vibration-damping protrusion so as to cover the antinode portion of the vibration mode. Therefore, a stable vibration-damping effect can be obtained for various surges in the rubber foot, and in particular, an effective vibration-damping effect can be obtained for surges of the rubber foot in multiple vibration modes.

[0032] The tenth aspect is a cylindrical vibration isolation device for a motor mount as described in any one of the first to ninth aspects, wherein the rubber foot is formed as a solid structure that continuously extends from the axial center portion of the inner shaft member and the outer cylinder member toward both axial sides, and the vibration-damping protrusion is respectively provided to protrude axially outward from both axial end surfaces of the rubber foot, so that the vibration-damping protrusions on both axial sides protruding from the above-mentioned axial end surfaces are continuously connected in the axial direction through the rubber foot.

[0033] According to the cylindrical vibration isolating device for a motor mount having a structure according to this embodiment, the rubber foot is continuous in the axial direction, so that the deformation mode of the rubber foot is stabilized, and the vibration reduction effect based on the vibration reduction protrusion provided to protrude axially outward from the rubber foot is stably exerted.

[0034] The eleventh embodiment is a cylindrical vibration isolation device for a motor mount as described in any one of the first to tenth embodiments, wherein the rubber foot is formed as a solid structure that continuously extends from the axial center portion of the inner shaft member and the outer cylinder member toward both axial sides, and the vibration-damping protrusion protrudes from both circumferential end surfaces of the rubber foot and is continuously arranged throughout the entire axial length of the rubber foot.

[0035] According to the cylindrical vibration isolating device for a motor mount having a structure according to this embodiment, the deformation mode of the rubber foot is stabilized by the continuous rubber foot in the axial direction, and the vibration reduction effect of the vibration reduction protrusion provided to protrude circumferentially outward from the rubber foot is stably exerted. In addition, the portion of the vibration reduction protrusion protruding circumferentially outward from the rubber foot is continuously provided over the entire axial length of the rubber foot, thereby making it possible to obtain a large vibration reduction effect of the circumferentially protruding portion of the vibration reduction protrusion.

[0036] In the twelfth embodiment, based on the cylindrical vibration isolation device for a motor mount described in any one of the first to eleventh embodiments, the rubber foot is formed as a solid structure that continuously extends from the axial center portion of the inner shaft member and the outer cylinder member toward both axial sides respectively, and the vibration-damping protrusion protrudes from the entire surrounding surface of the rubber foot and is continuously arranged in a ring shape.

[0037] According to the cylindrical vibration isolating device for a motor mount having a structure according to this embodiment, the rubber foot is continuous in the axial direction, so that the deformation mode of the rubber foot is stabilized, and the vibration reduction effect by the vibration reduction protrusion is stably exerted. In addition, since the vibration reduction protrusion is provided to protrude from the rubber foot to the entire surrounding surface including both sides in the axial direction and both sides in the circumferential direction, the protrusion height of the vibration reduction protrusion from the rubber foot can be suppressed, and the vibration reduction effect by the vibration reduction protrusion can be greatly obtained.

[0038] The thirteenth method is a cylindrical vibration isolation device for a motor mount formed by connecting an inner shaft member and an outer tube member via a main rubber elastic body, wherein the main rubber elastic body is provided with a vibration-damping protrusion which is located in the middle part separated from either the inner shaft member or the outer tube member in the radial direction and protrudes on the surface, and the vibration-damping protrusion constitutes a first vibration-damping part and a second vibration-damping part having different natural vibration frequencies.

[0039] According to the cylindrical vibration isolating device for a motor mount formed in a structure according to this embodiment, the vibration-damping protrusion includes a first vibration-damping portion and a second vibration-damping portion having mutually different natural vibration frequencies, thereby achieving a wider vibration-damping effect exerted by the vibration-damping protrusion (widening of the frequency region in which the vibration-damping effect is exerted).

[0040] A fourteenth aspect is the cylindrical vibration isolating device for a motor mount according to the thirteenth aspect, wherein the first vibration damping portion and the second vibration damping portion are constituted by the respective vibration damping protrusions.

[0041] According to the cylindrical vibration isolating device for a motor mount configured according to this aspect, the arrangement, shape, size, etc. of the first vibration damping portion and the second vibration damping portion can be set with a large degree of freedom.

[0042] A fifteenth aspect is the cylindrical vibration isolating device for a motor mount according to the thirteenth aspect, wherein the first vibration damping portion and the second vibration damping portion are formed by different portions of the one vibration damping protrusion.

[0043] According to the cylindrical vibration isolating device for a motor mount having a structure according to this embodiment, an effective vibration reduction effect against surge can be obtained in a wider frequency range by a single vibration reduction protrusion. In addition, this embodiment does not necessarily mean that only one vibration reduction protrusion must be provided. For example, a plurality of vibration reduction protrusions having a first vibration reduction portion and a second vibration reduction portion at different portions can be provided on the main rubber elastic body.

[0044] The sixteenth method is a cylindrical vibration isolation device for a motor mount, in which an inner shaft member and an outer cylinder member are connected by a main rubber elastic body, wherein the main rubber elastic body is provided with a vibration-damping protrusion protruding axially outward on the surface of the axial end portion, and the vibration-damping protrusion has a mass portion formed as a thick wall at the front end portion in the protruding direction.

[0045] According to the cylindrical vibration isolating device for a motor mount having a structure according to this embodiment, since the mass of the vibration-damping protrusion is large due to the thick-walled mass portion, the intended vibration-damping effect can be efficiently obtained. In addition, since the base end portion of the vibration-damping protrusion is thinner than the front end portion, the deformation rigidity of the base end portion of the vibration-damping protrusion is suppressed, and the deformation of the vibration-damping protrusion relative to the vibration input is efficiently generated.

[0046] Effects of the Invention

[0047] According to the present invention, it is possible to improve the vibration-proofing performance against high-frequency vibrations that are a problem in motor mounts. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Figure 1 It is a front view showing a motor mount according to a first embodiment of the present invention.

[0049] Figure 2 yes Figure 2 II-II sectional view.

[0050] Figure 3 It is a front view showing a motor mount according to a second embodiment of the present invention.

[0051] Figure 4 It is a front view showing a motor mount according to a third embodiment of the present invention.

[0052] Figure 5 It is a front view showing a motor mount according to a fourth embodiment of the present invention.

[0053] Figure 6 It is a front view showing a motor mount according to a fifth embodiment of the present invention.

[0054] Figure 7 It is a front view showing a motor mount according to a sixth embodiment of the present invention.

[0055] Figure 8 It is a front view showing a motor mount according to a seventh embodiment of the present invention.

[0056] Fig. 9 It is a front view showing a motor mount according to an eighth embodiment of the present invention.

[0057] Fig.10 yes Fig. 9 XX cross-sectional view.

[0058] Fig.11 It is a front view showing a motor mount according to a ninth embodiment of the present invention.

[0059] Fig.12 It is a front view showing a motor mount according to a tenth embodiment of the present invention.

[0060] Fig.13 yes Fig.12 XIII-XIII sectional view.

[0061] Fig.14 It is a front view showing a motor mount according to an eleventh embodiment of the present invention.

[0062] Fig.15 It is a longitudinal sectional view showing a motor mount according to a twelfth embodiment of the present invention.

[0063] Fig.16 It is a front view showing a motor mount according to a thirteenth embodiment of the present invention.

[0064] Fig.17 yes Fig.16 XVII-XVII sectional view.

[0065] Fig.18 It is a front view showing a motor mount according to a fourteenth embodiment of the present invention.

[0066] Fig.19 yes Fig.18 XIX-XIX sectional view. DETAILED DESCRIPTION

[0067] Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[0068] exist Figure 1 , Figure 2 1 shows a motor mount 10 for an electric vehicle as a first embodiment of a cylindrical vibration isolating device for a motor mount according to the present invention. The motor mount 10 has a structure in which an inner shaft member 12 and an outer cylinder member 14 are connected by a main rubber elastic body 16. In the following description, in principle, the up-down direction, the front-back direction, and the left-right direction refer to Figure 1 The up and down directions in Figure 2 The left and right directions in Figure 1 The left and right direction in .

[0069] The inner shaft member 12 is a hard member formed of metal or synthetic resin, and is formed into a generally cylindrical shape with a thick wall and a small diameter. The center hole of the inner shaft member 12 is a bolt hole 18 that penetrates in the axial direction, and the inner shaft member 12 is mounted on a power unit including an electric motor by inserting a mounting bolt (not shown) through the bolt hole 18.

[0070] The outer cylinder member 14 is a hard member formed of metal or synthetic resin, and is formed into a thin-walled, large-diameter, generally cylindrical shape. The outer cylinder member 14 has a smaller axial length dimension than the inner shaft member 12. The outer cylinder member 14 is installed in an externally inserted state by an outer bracket (not shown), and is installed on the vehicle body via the outer bracket.

[0071] The inner shaft member 12 is inserted and arranged in a separated state on the inner periphery of the outer cylinder member 14, and these inner shaft member 12 and the outer cylinder member 14 are connected to each other through the main rubber elastic body 16. The main rubber elastic body 16 of this embodiment has four rubber feet 20, 20, 20, 20. The rubber feet 20 extend radially from the inner shaft member 12 toward the outer cylinder member 14, and the end of the inner peripheral side is vulcanized and bonded to the outer peripheral surface of the inner shaft member 12, and the end of the outer peripheral side is vulcanized and bonded to the inner peripheral surface of the outer cylinder member 14. In the rubber feet 20, the inner peripheral ends are connected to each other in the circumferential direction by the inner peripheral connecting portion 22 extending in the circumferential direction, and the outer peripheral ends are connected to each other in the circumferential direction by the outer peripheral connecting portion 24 extending in the circumferential direction. The inner peripheral connecting portion 22 is fixedly mounted on the outer peripheral surface of the inner shaft member 12, and the outer peripheral connecting portion 24 is fixedly mounted on the inner peripheral surface of the outer cylinder member 14. In the present embodiment, two rubber feet 20a, 20a extend in the vertical direction on both upper and lower sides relative to the inner shaft member 12, and the other two rubber feet 20b, 20b extend in the left-right direction on both left and right sides relative to the inner shaft member 12. Therefore, the four rubber feet 20a, 20a, 20b, 20b are arranged in a cross shape as a whole.

[0072] like Figure 2 As shown in FIG. 1 , the rubber foot 20, except for the inner circumference vibration-damping protrusion 30 and the outer circumference vibration-damping protrusion 32 described later, is formed as a tapered surface 26 with both axial end surfaces facing the outer circumference and tilted inward in the axial direction, and the axial outer dimension decreases toward the outer circumference. The rubber foot 20 is formed as a solid structure that continuously extends from the axial center portion of the inner shaft member 12 and the outer cylinder member 14 toward both axial sides without any recess or void in the middle of the axial direction.

[0073] A space 28 is formed between two rubber feet 20, 20 adjacent to each other in the circumferential direction, and passes through in the axial direction. The space 28 is formed in the shape of a hole whose circumferential walls are the rubber feet 20, the rubber feet 20, the inner peripheral connecting portion 22, and the outer peripheral connecting portion 24. Since the space 28 is formed between the rubber feet 20 extending in the up-down direction and the rubber feet 20 extending in the left-right direction, the overall hole cross-sectional shape is formed in which the width becomes wider in the circumferential direction toward the outer periphery. In addition, in the present embodiment, since the outer peripheral end of the rubber foot 20 is formed in an expanded shape that expands toward the outer periphery and toward the circumferential outside, the outer peripheral end of the space 28 becomes narrower in the circumferential direction toward the outer periphery.

[0074] An inner circumferential vibration-damping protrusion 30 as a vibration-damping protrusion is integrally formed on the rubber foot 20. The inner circumferential vibration-damping protrusion 30 is formed in a curved plate shape that is curved in the circumferential direction, and protrudes from the axial end surface of the rubber foot 20 toward the axial outer side. The inner circumferential vibration-damping protrusion 30 extends straightly in the axial direction with a substantially constant cross-sectional shape. The protruding front end surface of the inner circumferential vibration-damping protrusion 30 is formed in a flat surface that extends in a substantially perpendicular direction to the axis. The inner circumferential vibration-damping protrusion 30 is located in the middle portion separated from either the inner axial member 12 or the outer cylindrical member 14 in the extension direction of the rubber foot 20 (the connection direction of the inner axial member 12 and the outer cylindrical member 14 based on the rubber foot 20), and is preferably arranged on the inner circumferential side of the center of the rubber foot 20. The inner circumferential vibration-damping protrusion 30 is provided on each rubber foot 20, and is provided on both axial sides protruding from the axial end surfaces of each rubber foot 20. The inner circumference vibration-damping protrusions 30 and the inner circumference vibration-damping protrusions 30 protruding from the rubber foot 20 to both outer sides in the axial direction are arranged at radial positions corresponding to each other, and the inner circumference vibration-damping protrusions 30 and the inner circumference vibration-damping protrusions 30 on both sides in the axial direction are continuously connected in the axial direction by forming the solid rubber foot 20. The inner circumference vibration-damping protrusions 30 provided on the four rubber feet 20a, 20a, 20b, 20b are arranged on substantially the same circumference.

[0075] An outer peripheral vibration-damping protrusion 32 serving as a vibration-damping protrusion is integrally formed on the rubber foot 20. The outer peripheral vibration-damping protrusion 32 is formed in a curved plate shape that is curved in the circumferential direction, and protrudes from the axial end surface of the rubber foot 20 toward the axial outer side. The outer peripheral vibration-damping protrusion 32 extends straightly in the axial direction with a substantially constant cross-sectional shape. The protruding front end surface of the outer peripheral vibration-damping protrusion 32 is formed in a flat surface that extends in a substantially perpendicular direction to the axis. The outer peripheral vibration-damping protrusion 32 is located in the middle portion separated from either the inner shaft member 12 or the outer cylinder member 14 in the extending direction of the rubber foot 20, and is preferably arranged on the outer peripheral side relative to the center of the rubber foot 20. The outer peripheral vibration-damping protrusion 32 is provided on each rubber foot 20, and is provided on both axial sides to protrude from both axial end surfaces of each rubber foot 20. The outer peripheral vibration-damping protrusions 32 and 32 protruding from the rubber foot 20 to both outer sides in the axial direction are arranged at radial positions corresponding to each other, and the outer peripheral vibration-damping protrusions 32 and 32 on both sides in the axial direction are continuously connected in the axial direction by forming the rubber foot 20 as a solid body. The outer peripheral vibration-damping protrusions 32 provided on the four rubber feet 20a, 20a, 20b, 20b are arranged on substantially the same circumference.

[0076] The inner circumference vibration damping protrusion 30 and the outer circumference vibration damping protrusion 32 are arranged in parallel and spaced apart from each other in the extending direction of the rubber foot 20. The inner circumference vibration damping protrusion 30 and the outer circumference vibration damping protrusion 32 are arranged at substantially equal positions relative to the rubber foot 20 in the extending direction of the rubber foot 20. More specifically, in the present embodiment, the distance d1 between the inner circumference vibration damping protrusion 30 and the outer circumference vibration damping protrusion 32 is formed to be shorter than any one of the distance d2 from the inner circumference end of the rubber foot 20 to the inner circumference vibration damping protrusion 30 (the distance from the inner circumference vibration damping protrusion 30 to the outer circumference surface of the inner shaft member 12) and the distance d3 from the outer circumference end of the rubber foot 20 to the outer circumference vibration damping protrusion 32 (the distance from the outer circumference vibration damping protrusion 32 to the inner circumference surface of the outer cylinder member 14). In addition, the inner circumference vibration damping protrusion 30 and the outer circumference vibration damping protrusion 32 are provided so that the thickness dimension in the radial direction is substantially the same as each other.

[0077] The inner circumference vibration-damping protrusion 30 and the outer circumference vibration-damping protrusion 32 are arranged so that the axial positions of the protruding front ends are substantially the same as each other. Figure 2 As shown in FIG. 2 , since the axial end surface of the rubber foot 20 is formed as the tapered surface 26, the length dimension of the inner circumference vibration-damping protrusion 30 in the protruding direction is smaller than the length dimension of the outer circumference vibration-damping protrusion 32 in the protruding direction. Due to the difference in the protruding length dimension of the inner circumference vibration-damping protrusion 30 and the outer circumference vibration-damping protrusion 32 from the rubber foot 20, the inner circumference vibration-damping protrusion 30 and the outer circumference vibration-damping protrusion 32 are set to have mutually different natural vibration frequencies. In the present embodiment, the inner circumference vibration-damping protrusion 30 becomes the first vibration-damping part, and the outer circumference vibration-damping protrusion 32 becomes the second vibration-damping part, and the first vibration-damping part and the second vibration-damping part are provided independently of each other. In addition, in the present embodiment, the natural vibration frequency of the inner circumference vibration-damping protrusion 30 having a smaller protruding length dimension is set to be higher than the natural vibration frequency of the outer circumference vibration-damping protrusion 32 having a larger protruding length dimension.

[0078] When the motor mount 10 having the above structure is mounted on a vehicle and vibration is input from the power unit side, the rubber legs 20 elastically deform to exert a vibration-proofing effect, thereby reducing the vibration applied to the vehicle body side.

[0079] However, electric vehicles using electric motors as a driving source may also have a problem of high dynamic spring in a high frequency region (e.g., 500 to 1000 Hz) caused by surging of the rubber feet 20, which is not a problem in conventional vehicles using internal combustion engines (engines) as a driving source. Therefore, in the motor mount 10 of the present embodiment, each rubber foot 20 is provided with an inner peripheral vibration damping protrusion 30 and an outer peripheral vibration damping protrusion 32, and these inner peripheral vibration damping protrusion 30 and outer peripheral vibration damping protrusion 32 are actively deformed in a resonant state to exert a vibration damping effect as a dynamic damper, thereby suppressing the high dynamic spring caused by surging of each rubber foot 20.

[0080] In the present embodiment, the rubber foot 20 is formed into a solid structure that is continuous in the axial direction, thereby stabilizing the deformation mode of the rubber foot 20. Therefore, the deformation mode of the inner circumference vibration-damping protrusion 30 and the outer circumference vibration-damping protrusion 32 supported by the rubber foot 20 is stabilized, and the vibration-damping effect by the inner circumference vibration-damping protrusion 30 and the outer circumference vibration-damping protrusion 32 is stably exerted.

[0081] Since the inner circumference vibration-damping protrusion 30 and the outer circumference vibration-damping protrusion 32 are formed as the first vibration-damping protrusion and the second vibration-damping protrusion having different natural vibration frequencies, the vibration-damping effect on the surge of the rubber foot 20 is exerted in a wider frequency range. In the present embodiment, since the first vibration-damping protrusion and the second vibration-damping protrusion are independently provided by the inner circumference vibration-damping protrusion 30 and the outer circumference vibration-damping protrusion 32 being different from each other, the first vibration-damping protrusion and the second vibration-damping protrusion can be adjusted more freely.

[0082] In addition, since the inner circumference vibration-damping protrusion 30 and the outer circumference vibration-damping protrusion 32 are arranged to be separated from each other in the extending direction of the rubber foot 20, for example, an effective vibration-damping effect can be obtained not only for surge in the first-order vibration mode, but also for surge in the second-order vibration mode.

[0083] exist Figure 3 2 shows a motor mount 40 for an electric vehicle as a second embodiment of the cylindrical vibration isolating device for a motor mount according to the present invention. The motor mount 40 has a structure in which an inner shaft member 12 and an outer cylinder member 14 are connected by a main rubber elastic body 42. In the following description, for components and parts that are substantially the same as those in the first embodiment, the same reference numerals are marked in the drawings and the description is omitted.

[0084] The main rubber elastic body 42 of the present embodiment includes a pair of left and right rubber feet 20b, 20b. In other words, the main rubber elastic body 42 of the present embodiment is formed into a structure as if the upper and lower rubber feet 20a, 20a are removed from the main rubber elastic body 16 of the first embodiment, and a pair of empty spaces 44, 44 extending in the circumferential direction with a length each less than half the circumference are formed between the left and right rubber feet 20b, 20b in the circumferential direction (with respect to the left and right rubber feet 20b, 20b and the upper and lower sides of the inner shaft member 12).

[0085] According to the motor mount 40 of the present embodiment, a soft spring characteristic based on the shear elasticity of the pair of rubber feet 20b, 20b can be obtained for vibration input in the vertical direction. In addition, the inner peripheral vibration-damping protrusion 30 and the outer peripheral vibration-damping protrusion 32 provided on each rubber foot 20b can effectively achieve a vibration-damping effect for surge of each rubber foot 20b.

[0086] As exemplified in this embodiment, the number of rubber legs may be plural, for example, three, or more than five. In addition, the plurality of rubber legs need not necessarily be arranged substantially evenly in the circumferential direction, and may be arranged staggered in the circumferential direction.

[0087] For example, it is also possible to Figure 4 As shown in the third embodiment of the motor mount 50, a main rubber elastic body 52 is provided with a pair of rubber feet 54, 54 inclined with respect to the left and right direction. In the motor mount 50, the pair of rubber feet 54, 54 are inclined downward with respect to the left and right direction from the inner periphery to the outer periphery, and a relatively hard support elasticity based on the compression spring component of the pair of rubber feet 54, 54 can be obtained for the shared support load of the power unit including the electric motor not shown, and the load resistance performance can be ensured. In addition, in the motor mount 50, the upper and lower spaces formed in the circumferential direction between the left and right rubber feet 54, 54 are different in shape due to the different circumferential lengths.

[0088] exist Figure 5 , a motor mount 60 for an electric vehicle is shown as a fourth embodiment of the cylindrical vibration isolating device for a motor mount according to the present invention. The main rubber elastic body 62 of the motor mount 60 has four rubber feet 20a, 20a, 20b, 20b arranged in a cross shape as in the first embodiment, and each rubber foot 20 is provided with an inner peripheral vibration damping protrusion 64 and an outer peripheral vibration damping protrusion 66.

[0089] The inner circumferential vibration-damping protrusions 64 protrude from both axial end surfaces of the rubber foot 20 toward both axial outer sides. In addition, the inner circumferential vibration-damping protrusions 64 protrude from both circumferential end surfaces of the rubber foot 20 toward both circumferential outer sides. Thus, the inner circumferential vibration-damping protrusions 64 protrude from the entire circumferential surface of the rubber foot 20 and are provided in a ring shape that is continuous around the entire circumference of the rubber foot 20. The portion of the inner circumferential vibration-damping protrusions 64 that protrudes from the rubber foot 20 toward both circumferential outer sides is continuously connected in the circumferential direction by the rubber foot 20 formed as a solid body, and is continuously provided over the entire axial length of the rubber foot 20.

[0090] The outer peripheral vibration-damping protrusions 66 protrude from both axial end surfaces of the rubber foot 20 toward both axial outer sides, respectively. In addition, the outer peripheral vibration-damping protrusions 66 protrude from both circumferential end surfaces of the rubber foot 20 toward both circumferential outer sides, respectively. Thus, the outer peripheral vibration-damping protrusions 66 protrude from the entire circumferential surface of the rubber foot 20 and are provided in a continuous ring shape along the entire circumference of the rubber foot 20. The portion of the outer peripheral vibration-damping protrusions 66 that protrudes from the rubber foot 20 toward both circumferential outer sides is continuously connected in the circumferential direction by the rubber foot 20 formed as a solid body, and is provided continuously over the entire axial length of the rubber foot 20.

[0091] According to the motor mount 60 having such an inner circumferential vibration-damping protrusion 64 and an outer circumferential vibration-damping protrusion 66, not only can a vibration-damping effect on the surge of the rubber foot 20 be obtained by deformation of the inner circumferential vibration-damping protrusion 64 and the outer circumferential vibration-damping protrusion 66 protruding axially outward from the rubber foot 20, but also a vibration-damping effect on the surge of the rubber foot 20 can be obtained by deformation of the inner circumferential vibration-damping protrusion 64 and the outer circumferential vibration-damping protrusion 66 protruding circumferentially outward from the rubber foot 20.

[0092] In addition, Figure 6 As shown in the fifth embodiment of the motor mount 70, a main rubber elastic body 72 is used which is a structure composed of a pair of rubber feet 20b, 20b extending in the left-right direction as in the second embodiment, an inner peripheral vibration-damping protrusion 64, and an outer peripheral vibration-damping protrusion 66. Figure 7 As shown in the sixth embodiment, the motor mount 80 uses a main rubber elastic body 82 composed of a pair of rubber legs 54 , 54 extending downwardly toward the left and right sides as in the third embodiment, and an inner peripheral vibration-damping protrusion 64 and an outer peripheral vibration-damping protrusion 66 .

[0093] In the fourth to sixth embodiments, the vibration-damping protrusions (64, 66) protruding both circumferentially and axially outward from the rubber foot 20 (54) are shown, but, for example, vibration-damping protrusions protruding only circumferentially outward and not axially may be used.

[0094] exist Figure 8 , a motor mount 90 for an electric vehicle is shown as a seventh embodiment of the cylindrical vibration isolating device for a motor mount according to the present invention. The main rubber elastic body 92 of the motor mount 90 is formed to have four rubber legs 20a, 20a, 20b, 20b extending in a cross shape, and each rubber leg 20 is provided with an inner peripheral vibration damping protrusion 94 and an outer peripheral vibration damping protrusion 96.

[0095] The inner circumferential vibration-damping projection 94 and the outer circumferential vibration-damping projection 96 are both formed into a curved plate shape extending in the circumferential direction, are formed integrally with the rubber foot 20 , and protrude from the axial end surface of the rubber foot 20 toward the axial outer side with a substantially constant cross-sectional shape.

[0096] The inner circumferential vibration-damping protrusion 94 is smaller in not only the axial protruding length dimension but also the circumferential length dimension than the outer circumferential vibration-damping protrusion 96. Due to the difference in shape and size as described above, the natural vibration frequencies of the inner circumferential vibration-damping protrusion 94 and the outer circumferential vibration-damping protrusion 96 are different from each other. In the present embodiment, the natural vibration frequency of the inner circumferential vibration-damping protrusion 94 as the first vibration-damping part is adjusted to be lower than the natural vibration frequency of the outer circumferential vibration-damping protrusion 96 as the second vibration-damping part.

[0097] As shown in the present embodiment, by making the circumferential length dimensions of the inner circumference vibration-damping protrusion 94 and the outer circumference vibration-damping protrusion 96 different from each other, the natural vibration frequencies of the inner circumference vibration-damping protrusion 94 and the outer circumference vibration-damping protrusion 96 can also be made different from each other. In addition, the size relationship between the circumferential length dimension of the inner circumference vibration-damping protrusion and the circumferential length dimension of the outer circumference vibration-damping protrusion can also be reversed.

[0098] exist Fig. 9 , Fig.10 1 shows a motor mount 100 for an electric vehicle as an eighth embodiment of the cylindrical vibration isolating device for a motor mount according to the present invention. The main rubber elastic body 102 of the motor mount 100 is formed to have four rubber legs 20a, 20a, 20b, 20b extending in a cross shape, and each rubber leg 20 is provided with an inner peripheral vibration damping protrusion 104 and an outer peripheral vibration damping protrusion 106.

[0099] The inner circumferential vibration damping protrusion 104 and the outer circumferential vibration damping protrusion 106, which are formed into a curved plate shape extending in the circumferential direction and protrude axially outward from the rubber foot 20, have different thickness dimensions in the extension direction (radial direction) of the rubber foot 20, and the inner circumferential vibration damping protrusion 104 is formed to be thinner than the outer circumferential vibration damping protrusion 106. Due to the difference in thickness dimensions of the inner circumferential vibration damping protrusion 104 and the outer circumferential vibration damping protrusion 106, different natural vibration frequencies are set for the inner circumferential vibration damping protrusion 104 and the outer circumferential vibration damping protrusion 106. In the present embodiment, the first vibration damping section and the second vibration damping section are independently provided by the inner circumferential vibration damping protrusion 104 and the outer circumferential vibration damping protrusion 106, and the natural vibration frequency of the inner circumferential vibration damping protrusion 104 as the first vibration damping section is adjusted to be lower than the natural vibration frequency of the outer circumferential vibration damping protrusion 106 as the second vibration damping section. Fig.10 As shown, the thickness dimension and the axial protrusion length dimension of the inner peripheral vibration damping protrusion 104 and the outer peripheral vibration damping protrusion 106 are different from each other, and as shown in FIG. Fig. 9 As shown, the circumferential lengths of the inner circumference vibration damping protrusion 104 and the outer circumference vibration damping protrusion 106 are substantially the same.

[0100] As shown in this embodiment, the natural vibration frequencies of the inner and outer vibration damping protrusions 104 and 106 can be made different by making the thicknesses of the inner and outer vibration damping protrusions 104 and 106 different from each other. In addition, the thickness of the inner vibration damping protrusions can be larger than that of the outer vibration damping protrusions.

[0101] exist Fig.11, a motor mount 110 for an electric vehicle is shown as a ninth embodiment of the cylindrical vibration isolating device for a motor mount according to the present invention. The main rubber elastic body 112 of the motor mount 110 includes four rubber feet 20a, 20a, 20b, 20b arranged in a cross shape, and the rubber feet 20a and 20a extending in the vertical direction are provided with a first vibration damping part 114 as a vibration damping protrusion, and the rubber feet 20b and 20b extending in the left-right direction are provided with a second vibration damping part 116 as a vibration damping protrusion.

[0102] The first vibration damping portion 114 protrudes axially outward from the axial end surface of the rubber foot 20a extending in the vertical direction, and is formed into a curved plate shape extending and bending in the circumferential direction. Fig. 9 The rubber foot 20 shown has only one first vibration damping portion 114 formed on one axial end surface. In addition, the first vibration damping portion 114 may be formed to protrude on both axial sides of the rubber foot 20a, or may be provided on only one axial side of the rubber foot 20a.

[0103] The second vibration damping portion 116 protrudes axially outward from the axial end surface of the rubber foot 20b extending in the left-right direction, and is formed into a curved plate shape extending and bending in the circumferential direction. Fig. 9 The rubber foot 20 shown has only one second vibration damping portion 116 formed on one axial end surface. In addition, the second vibration damping portion 116 may be formed to protrude on both axial sides of the rubber foot 20b, or may be provided on only one axial side of the rubber foot 20b.

[0104] The circumferential lengths of the first vibration damper 114 and the second vibration damper 116 are different from each other, and the circumferential length of the first vibration damper 114 is larger than the circumferential length of the second vibration damper 116. Therefore, the natural vibration frequencies of the first vibration damper 114 and the second vibration damper 116 are different from each other. In the present embodiment, the natural vibration frequency of the first vibration damper 114 is adjusted to be lower than the natural vibration frequency of the second vibration damper 116.

[0105] The axial lengths of the first vibration damper 114 and the second vibration damper 116 may be different from each other, but in the present embodiment, they are the same. The positions of the protruding front end surfaces of the first vibration damper 114 and the second vibration damper 116 are not particularly limited, and for example, they may be set so as not to protrude axially outward compared to the outer cylinder member 14. In the present embodiment, the first vibration damper 114 does not protrude circumferentially outward from the rubber foot 20, but may protrude circumferentially outward from the rubber foot 20 like the vibration damping protrusions (64, 66) shown in the fourth embodiment.

[0106] There is no need to provide a plurality of vibration-damping protrusions in the extending direction of the rubber leg 20 , and as in the present embodiment, a vibration-damping protrusion (the first vibration-damping portion 114 and the second vibration-damping portion 116 ) may be provided at only one location in the extending direction of the rubber leg 20 .

[0107] According to the motor mount 110 of the present embodiment, the natural vibration frequencies of the first vibration damper 114 and the first vibration damper 114 provided in the upper and lower rubber feet 20a and the natural vibration frequencies of the second vibration damper 116 and the second vibration damper 116 provided in the left and right rubber feet 20b and the rubber feet 20b are different from each other, so that the vibration damping effect against the surge of the rubber feet 20 can be effectively obtained over a wider frequency range. In addition, in the present embodiment, the upper and lower rubber feet 20a and the rubber feet 20a are respectively provided with the vibration damping protrusions (first vibration damper 114) set to the same natural vibration frequency, but, for example, the natural vibration frequencies of the vibration damping protrusions provided in the upper and lower rubber feet 20a and the rubber feet 20a can also be different from each other. Similarly, the vibration damping protrusions provided in the left and right rubber feet 20b and the rubber feet 20b can also be set to have different natural vibration frequencies. For example, by providing the four rubber feet 20a, 20a, 20b, and 20b with vibration-damping protrusions having different natural vibration frequencies, respectively, it is possible to exert an effective vibration-damping effect on surge in a wider frequency range.

[0108] In the motor mount 110 shown in the ninth embodiment, the first damper 114 and the second damper 116 are described as having different natural frequencies due to the difference in circumferential length dimensions. However, for example, Fig.12 , Fig.13 As in the main rubber elastic body 122 of the motor mount 120 of the tenth embodiment shown in the figure, by providing the first vibration damper 124 with a large thickness dimension on the upper and lower rubber feet 20a, rubber feet 20a, and providing the second vibration damper 126 with a small thickness dimension on the left and right rubber feet 20b, rubber feet 20b, vibration damper protrusions with different natural vibration frequencies are formed. In addition, the natural vibration frequencies of the first vibration damper and the second vibration damper can also be made different by making the protrusion length dimension from the rubber foot 20 different.

[0109] exist Fig.14 1 shows a motor mount 130 for an electric vehicle as an eleventh embodiment of a cylindrical vibration isolating device for a motor mount according to the present invention. In the motor mount 130, the inner shaft member 12 and the outer cylinder member 14 are connected to each other through a main rubber elastic body 132 throughout the entire circumference in the radial direction, and the main rubber elastic body 132 is formed into a cylindrical shape without rubber feet and spaces.

[0110] The main rubber elastic body 132 is integrally formed with a vibration-damping protrusion 134 that protrudes from the axial end surface toward the axial outer side. The vibration-damping protrusion 134 is formed into a circumferentially continuous annular or cylindrical shape, and is located between the inner shaft member 12 and the outer cylinder member 14 in the radial direction, and is separated from both the inner shaft member 12 and the outer cylinder member 14 in the radial direction.

[0111] The radial thickness dimension of the vibration-damping protrusion 134 changes in the circumferential direction, and the upper and lower side portions are formed into the thin-walled first vibration-damping portion 136, and the left and right side portions are formed into the thick-walled second vibration-damping portion 138. In summary, in the present embodiment, only one vibration-damping protrusion 134 is provided which is continuous in the circumferential direction. In the one vibration-damping protrusion 134, the first vibration-damping portion 136 and the second vibration-damping portion 138, which have different thickness dimensions, are respectively partially provided at different positions in the circumferential direction. The thickness dimension of the vibration-damping protrusion 134 gradually changes in the circumferential direction, and the first vibration-damping portion 136 and the second vibration-damping portion 138 are continuously provided on the smooth inner circumferential surface and the outer circumferential surface. In the vibration-damping protrusion 134 of the present embodiment, the outer circumferential surface is formed into an ellipse with the left-right direction as the major axis, and the inner circumferential surface is formed into an ellipse with the vertical direction as the major axis, so that the thickness dimension of the left and right sides is larger than the thickness dimension of the upper and lower sides.

[0112] The first vibration damper 136 and the second vibration damper 138 have different natural vibration frequencies due to the different radial thickness dimensions. As a result, the vibration damping protrusion 134 (the first vibration damper 136 and the second vibration damper 138) can effectively exert the vibration damping effect of the main rubber elastic body 132 in a wider frequency range.

[0113] Furthermore, the vibration-damping protrusions 134 may be provided on both axial sides of the main rubber elastic body 132. In this case, the circumferential positions, the number of formations, the circumferential formation ranges, etc. of the vibration-damping protrusions 134, the vibration-damping protrusions 134, the first vibration-damping parts 136, and the second vibration-damping parts 138 on both axial sides may be the same or different.

[0114] For example, a plurality of annular or even cylindrical vibration-damping protrusions may be concentrically provided for a cylindrical main rubber elastic body that is continuous throughout the entire circumference as shown in the present embodiment. In this case, for example, the natural vibration frequencies of the plurality of vibration-damping protrusions may be made different from each other by making the thickness and protrusion length of the plurality of vibration-damping protrusions different from each other.

[0115] In addition, in the vibration-damping protrusions provided in the circumferential portion of the plurality of rubber legs 20 , first and second vibration-damping portions having different natural frequencies set by differences in thickness, protrusion length, etc. may be provided locally in the circumferential direction.

[0116] In the vibration-damping protrusion, three or more portions having mutually different natural frequencies may be set.

[0117] exist Fig.15 1 shows a motor mount 140 for an electric vehicle as a twelfth embodiment of a cylindrical vibration isolating device for a motor mount according to the present invention. The motor mount 140 includes vibration-damping projections 144 projecting outward in the axial direction from both axial end surfaces of a main rubber elastic body 142 .

[0118] The vibration-damping protrusion 144 has a radial thickness dimension that changes in the axial direction as the protruding direction, and the protruding tip portion is formed as a mass portion 146 that is thicker than the base end portion. In the present embodiment, an example is shown in which the vibration-damping protrusion 144 is provided locally in the circumferential direction relative to the rubber feet 20a and 20b, but the vibration-damping protrusion 144 may be provided locally in the circumferential direction as in the first to third embodiments, or may be provided continuously throughout the entire circumference as in the eleventh embodiment.

[0119] By providing a mass portion 146 at the protruding front end portion of the vibration-damping protrusion 144, it is possible to change the natural vibration frequency of the vibration-damping protrusion 144 with a large degree of freedom according to the thickness, axial length, etc. of the mass portion 146 without changing the circumferential length, axial protruding length, thickness in the base end portion, etc. of the vibration-damping protrusion 144.

[0120] exist Fig.16 , Fig.17 1 shows a motor mount 150 for an electric vehicle as a thirteenth embodiment of the cylindrical vibration isolating device for a motor mount according to the present invention. The main rubber elastic body 152 of the motor mount 150 has four rubber feet 20a, 20a, 20b, 20b extending in a cross shape, and has a structure in which the rubber feet 20a, 20b adjacent to each other in the circumferential direction are connected in the circumferential direction by a vibration-damping protrusion 154.

[0121] The vibration-damping protrusion 154 is formed in a curved plate shape that is bent and extended in the circumferential direction, and is disposed between the circumferentially adjacent rubber feet 20a and 20b, and both circumferential ends are integrally continuous with each of the rubber feet 20a and 20b. In other words, the vibration-damping protrusion 154 protrudes from the circumferential end surfaces of the circumferentially adjacent rubber feet 20a and 20b toward the circumferential inner side of the void 28. Both circumferential ends of the vibration-damping protrusion 154 are continuous with respect to the middle of the extension direction of the rubber feet 20, and the void 28 is divided into two equal parts into an inner circumferential side and an outer circumferential side by the vibration-damping protrusion 154.

[0122] The vibration-damping protrusion 154 may protrude in the axial direction relative to the rubber foot 20, but in the present embodiment, it does not protrude in the axial direction relative to the rubber foot 20, and the axial end surface of the vibration-damping protrusion 154 constitutes a part of the tapered surface 26 as the axial end surface of the rubber foot 20. The axial width dimension of the vibration-damping protrusion 154 is substantially constant in the circumferential direction. The axial width dimension W of the portion of the vibration-damping protrusion 154 located between the rubber feet 20a and the rubber feet 20b in the circumferential direction is larger than the circumferential length dimension L of the portion of the vibration-damping protrusion 154, and preferably, the axial width dimension W is twice or more of the circumferential length dimension L.

[0123] According to the motor mount 150 of the present embodiment as described above, the surging of the rubber feet 20 is reduced or even eliminated by the vibration-damping protrusions 154 provided between the circumferentially adjacent rubber feet 20 and the circumferentially adjacent rubber feet 20, thereby preventing high-frequency abnormal noise caused by the surging of the rubber feet 20.

[0124] The vibration-damping protrusion 154 of the present embodiment is supported in a double-supported manner by being continuous with the rubber feet 20 and the rubber feet 20 at both ends in the circumferential direction. Therefore, the vibration-damping protrusion 154 is different in deformation mode from the vibration-damping protrusion (30, 32) supported by the rubber feet 20 in a single-supported manner only at the end on the inner side in the axial direction as in the first embodiment, so it is easy to set characteristics different from the vibration-damping protrusion (30, 32) protruding in the axial direction as in the first embodiment.

[0125] Furthermore, two or more vibration-damping protrusions 154 may be provided between the circumferentially adjacent rubber feet 20a and 20b so as to be spaced apart from each other in the radial direction. Furthermore, it is not necessary to provide the vibration-damping protrusions 154 in all the spaces 28, and even the rubber feet 20a and 20b disposed adjacent to each other in the circumferential direction may not be connected by the vibration-damping protrusions 154. Furthermore, it is also possible to combine the vibration-damping protrusions 154 that connect the rubber feet 20a and 20b in the circumferential direction shown in this embodiment with the vibration-damping protrusions that protrude axially from the rubber feet 20 shown in the first embodiment and the seventh to tenth embodiments.

[0126] exist Fig.18 , Fig.19 14 shows a motor mount 160 for an electric vehicle as a cylindrical anti-vibration device for a motor mount according to the present invention. The main rubber elastic body 162 of the motor mount 160 includes a pair of rubber feet 20a, 20a extending in the up-down direction, and each rubber foot 20a is provided with a vibration-damping protrusion 164 protruding from the axial end surface toward the axial outer side. In addition, a pair of empty spaces 166, 166 are formed between the rubber feet 20a, 20a in the circumferential direction (on the left and right sides of the rubber feet 20a, 20a and the inner shaft member 12).

[0127] The vibration-damping protrusion 164 is formed into a plate-like shape that extends linearly in the connection direction of the inner shaft member 12 and the outer cylinder member 14 based on the rubber foot 20a (the extension direction of the rubber foot 20a). The inner peripheral end of the vibration-damping protrusion 164 of the present embodiment is integrally continuous with the inner peripheral connection part 22, and the outer peripheral end is integrally continuous with the outer peripheral connection part 24. In addition, each vibration-damping protrusion 164 of the present embodiment has a constant circumferential width dimension that is smaller than the circumferential width dimension of the rubber foot 20a, and extends linearly in the radial direction with a radial length dimension larger than the circumferential width dimension at the center of the width direction (circumferential direction) of the axial end face of the rubber foot 20a. Moreover, in the motor mount 160 of the present embodiment, the main vibration input direction in the assembly state to the vehicle is the left-right direction, and the extension direction of the vibration-damping protrusion 164 is approximately orthogonal to the main vibration input direction. In this way, if the extension direction of the vibration-damping protrusion 164 is a direction orthogonal to the main vibration input direction, since the vibration-damping protrusion 164 is shear-deformed when the main vibration is input, the deformation of the vibration-damping protrusion 164 is reduced compared to the case where the vibration-damping protrusion 164 is compressed in the extension direction.

[0128] According to the vibration-damping protrusion 164 extending in the extending direction of the rubber foot 20a as described above, an effective vibration-damping effect can be expected not only for surge in the first-order vibration mode but also for surge in the multi-order vibration mode. That is, in the multi-order vibration mode, the amplitude of the bending deformation of the rubber foot 20a increases at multiple locations in the extending direction of the rubber foot 20a, but since the vibration-damping protrusion 164 extending in the extending direction of the rubber foot 20a is located at all of the multiple locations (parts that become antinodes of the vibration mode) where the bending deformation of the rubber foot 20a increases, the vibration-damping effect is effectively exerted. In addition, the vibration-damping protrusion 164 does not need to extend strictly in the extending direction (radial direction) of the rubber foot 20a, and as long as it extends in the extending direction of the rubber foot 20a as a whole, it may be inclined or curved relative to the extending direction of the rubber foot 20a, and the circumferential width dimension may be changed. In addition, a plurality of vibration-damping protrusions 164 may be provided in the axial end surface of the rubber foot 20a so as to be spaced from each other in the circumferential direction.

[0129] The embodiments of the present invention are described in detail above, but the present invention is not limited to the specific description. For example, the plurality of rubber feet may have vibration-damping protrusions of different shapes, different numbers, or different configurations.

[0130] When a plurality of vibration-damping protrusions are provided, the natural vibration frequencies of these vibration-damping protrusions may be set to be the same as each other.

[0131] The structures shown in the first to fourteenth embodiments can be appropriately combined and adopted. That is, for example, the vibration-damping protrusions shown in different embodiments can be combined and applied.

[0132] The vibration-damping protrusion is not limited to a plate shape, and may be a rod shape protruding in a dot shape, etc. In addition, the vibration-damping protrusion arranged in a circumferentially extending manner does not necessarily need to be bent and extended in the circumferential direction, and may be a flat plate shape or may be bent in a manner inclined toward the circumferential outside and toward the outer periphery.

[0133] When the main rubber elastic body includes a plurality of rubber feet, it is not necessary to provide the vibration-damping protrusions on all of the plurality of rubber feet. Only one or some of the plurality of rubber feet may be provided with the vibration-damping protrusions, and the other rubber feet may not be provided with the vibration-damping protrusions.

[0134] In such Fig.14 In the main rubber elastic body of the continuous structure without the rubber foot as shown, the vibration-damping protrusion may be provided locally in the circumferential direction. In this case, a plurality of vibration-damping protrusions spaced apart from each other in the circumferential direction may be provided.

[0135] At least one of the inner shaft member 12 and the outer tube member 14 may be non-adhesively mounted to the main rubber elastic body 16. The inner shaft member 12 and the outer tube member 14 may have radial centers (central axes) offset from each other and axial centers offset from each other.

[0136] Description of Reference Numerals

[0137] 10: Motor mounting member (first embodiment);

[0138] 12: Inner shaft component;

[0139] 14: outer cylinder member;

[0140] 16: Main rubber elastic body;

[0141] 18: Bolt hole;

[0142] 20 (20a, 20b): rubber feet;

[0143] 22: inner peripheral connection part;

[0144] 24: peripheral connection portion;

[0145] 26: conical surface;

[0146] 28: empty space;

[0147] 30: inner circumference vibration-damping protrusion (vibration-damping protrusion; first vibration-damping part);

[0148] 32: peripheral vibration-damping protrusion (vibration-damping protrusion; second vibration-damping part);

[0149] 40: Motor mounting member (second embodiment);

[0150] 42: main rubber elastic body;

[0151] 44: empty space;

[0152] 50: Motor mounting member (third embodiment);

[0153] 52: main rubber elastic body;

[0154] 54: Rubber feet;

[0155] 56a, 56b: empty space;

[0156] 60: Motor mounting member (fourth embodiment);

[0157] 62: main rubber elastic body;

[0158] 64: inner circumference vibration-damping protrusion (vibration-damping protrusion; first vibration-damping part);

[0159] 66: peripheral vibration-damping protrusion (vibration-damping protrusion; second vibration-damping portion);

[0160] 70: Motor mounting member (fifth embodiment);

[0161] 72: main rubber elastic body;

[0162] 80: Motor mounting member (sixth embodiment);

[0163] 82: main rubber elastic body;

[0164] 90: Motor mounting member (seventh embodiment);

[0165] 92: main rubber elastic body;

[0166] 94: inner circumference vibration-damping protrusion (vibration-damping protrusion; first vibration-damping part);

[0167] 96: peripheral vibration-damping protrusion (vibration-damping protrusion; second vibration-damping portion);

[0168] 100: Motor mounting member (eighth embodiment);

[0169] 102: main rubber elastic body;

[0170] 104: inner circumference vibration-damping protrusion (vibration-damping protrusion; first vibration-damping part);

[0171] 106: outer peripheral vibration-damping protrusion (vibration-damping protrusion; second vibration-damping part);

[0172] 110: Motor mounting member (ninth embodiment);

[0173] 112: main rubber elastic body;

[0174] 114: first vibration-damping portion (vibration-damping protrusion);

[0175] 116: second vibration-damping portion (vibration-damping protrusion);

[0176] 120: Motor mounting member (tenth embodiment);

[0177] 122: main rubber elastic body;

[0178] 124: first vibration-damping portion (vibration-damping protrusion);

[0179] 126: second vibration damping portion (vibration damping protrusion);

[0180] 130: Motor mounting member (eleventh embodiment);

[0181] 132: main rubber elastic body;

[0182] 134: vibration-damping protrusion;

[0183] 136: first vibration damping unit;

[0184] 138: second vibration damping unit;

[0185] 140: Motor mounting member (twelfth embodiment);

[0186] 142: main rubber elastic body;

[0187] 144: vibration-damping protrusion;

[0188] 146: Quality Department;

[0189] 150: Motor mounting member (thirteenth embodiment);

[0190] 152: main rubber elastic body;

[0191] 154: vibration-damping protrusion;

[0192] 160: Motor mounting member (fourteenth embodiment);

[0193] 162: main rubber elastic body;

[0194] 164: vibration-damping protrusion;

[0195] 166: Empty space.

Claims

1. A cylindrical vibration isolating device for a motor mount, wherein an inner shaft member and an outer cylinder member are connected via a main rubber elastic body, wherein: The main rubber elastic body includes a plurality of rubber legs extending from the inner shaft member toward the outer tube member to connect the inner shaft member and the outer tube member to each other. The rubber foot is provided with a plurality of vibration-damping protrusions which are located in an intermediate portion separated from either the inner shaft member or the outer cylinder member in the connection direction and protrude on the surface. The plurality of vibration-damping protrusions are arranged in parallel and spaced apart from each other in the connecting direction of the rubber leg.

2. The cylindrical vibration isolating device for a motor mount according to claim 1, wherein: A plurality of different natural vibration frequencies are set in the plurality of vibration-damping protrusions provided on the rubber foot.

3. The cylindrical vibration isolating device for a motor mount according to claim 2, wherein: The plurality of different natural frequencies are set by making the protrusion dimensions of the vibration-damping protrusions from the rubber feet different.

4. The cylindrical vibration isolating device for a motor mount according to claim 2 or 3, wherein: The plurality of different natural frequencies are set by making the thickness dimension in the radial direction different in the vibration-damping protrusion.

5. The cylindrical vibration isolating device for a motor mount according to any one of claims 1 to 4, wherein: The plurality of vibration-damping protrusions are arranged substantially evenly with respect to the rubber leg in a connection direction of the rubber leg.

6. The cylindrical vibration isolating device for a motor mount according to any one of claims 1 to 5, wherein: The distance between the vibration-damping protrusions arranged adjacent to each other in the connecting direction of the rubber leg is shorter than any one of the distance from the innermost vibration-damping protrusion to the inner peripheral end of the rubber leg and the distance from another vibration-damping protrusion located at the outermost periphery to the outer peripheral end of the rubber leg.

7. A cylindrical vibration isolating device for a motor mount, wherein an inner shaft member and an outer cylinder member are connected via a main rubber elastic body, wherein: The main rubber elastic body includes a plurality of rubber legs extending from the inner shaft member toward the outer tube member to connect the inner shaft member and the outer tube member to each other. Between the circumferentially adjacent rubber feet, a vibration-damping protrusion is provided to connect the rubber feet to each other in the circumferential direction. The vibration-damping protrusion has an axial dimension larger than a circumferential dimension at a portion located between the rubber legs in the circumferential direction.

8. The cylindrical vibration isolating device for a motor mount according to claim 7, wherein: Both axial ends of the vibration-damping protrusion do not protrude axially outward relative to the axial end surface of the rubber foot.

9. A cylindrical vibration isolating device for a motor mount, wherein an inner shaft member and an outer cylinder member are connected via a main rubber elastic body, wherein: The main rubber elastic body includes a plurality of rubber legs extending from the inner shaft member toward the outer tube member to connect the inner shaft member and the outer tube member to each other. The rubber foot is provided with a vibration-damping protrusion protruding on the surface. The vibration-damping protrusion extends along a connecting direction of the rubber arm.

10. The cylindrical vibration isolating device for a motor mount according to any one of claims 1 to 9, wherein: The rubber feet are formed into a solid structure extending continuously from the axial center of the inner shaft member and the outer cylinder member toward both axial sides. The vibration-damping protrusions protrude axially outward from both axial end surfaces of the rubber foot, respectively, and the vibration-damping protrusions on both axial sides protruding from both axial end surfaces are continuously connected in the axial direction through the rubber foot.

11. The cylindrical vibration isolating device for a motor mount according to any one of claims 1 to 10, wherein: The rubber feet are formed into a solid structure extending continuously from the axial center of the inner shaft member and the outer cylinder member toward both axial sides. The vibration-damping protrusions protrude from both end surfaces in the circumferential direction of the rubber foot, respectively, and are continuously provided over the entire axial length of the rubber foot.

12. The cylindrical vibration isolating device for a motor mount according to any one of claims 1 to 11, wherein: The rubber feet are formed into a solid structure extending continuously from the axial center of the inner shaft member and the outer cylinder member toward both axial sides. The vibration-damping protrusion protrudes from the entire peripheral surface of the rubber foot and is continuously provided in a ring shape.

13. A cylindrical vibration isolating device for a motor mount, wherein an inner shaft member and an outer cylinder member are connected via a main rubber elastic body, wherein: The main rubber elastic body is provided with a vibration-damping protrusion protruding on the surface at a middle portion separated from either the inner shaft member or the outer cylinder member in a radial direction. The vibration-damping protrusions constitute a first vibration-damping portion and a second vibration-damping portion having mutually different natural vibration frequencies.

14. The cylindrical vibration isolating device for a motor mount according to claim 13, wherein: The first vibration damping portion and the second vibration damping portion are constituted by the respective vibration damping protrusions.

15. The cylindrical vibration isolating device for a motor mount according to claim 13, wherein: The first vibration damping portion and the second vibration damping portion are formed by different portions of the one vibration damping protrusion.

16. A cylindrical vibration isolating device for a motor mount, wherein an inner shaft member and an outer cylindrical member are connected via a main rubber elastic body, wherein: The main rubber elastic body is provided with a vibration-damping protrusion protruding axially outward on the surface of the axial end portion. The vibration-damping protrusion has a mass portion whose front end portion in the protruding direction is formed to be thick.

Images