vibration isolator

Abstract

The present application provides a new configuration of a vibration isolation device, which can control the vibration isolation characteristics with excellent energy efficiency by efficiently applying a control magnetic force to a sealed magnetic functional fluid. In a vibration isolation device (10) that controls the vibration isolation characteristics by applying a magnetic force from a magnetic field generating unit (56) to a throttle passage (40) that communicates fluid chambers (38, 38) in which a magnetic functional fluid (39) is sealed, an intermediate cylinder member (24) in which an outer cylinder member (16) composed of a non-magnetic material is fixedly fitted is composed of a ferromagnetic material, and a magnetic field acting opening portion (32) is provided in the intermediate cylinder member (24) at a position corresponding to the throttle passage (40).

Description

Technical Field

[0001] This invention relates to a fluid-sealed vibration damping device that utilizes the flow of fluid sealed within an internal fluid chamber, and more particularly to a fluid-sealed vibration damping device employing a magnetically functional fluid whose flow characteristics change due to variations in a magnetic field. Background Technology

[0002] Previously, a fluid-sealed vibration damping device was known as a type of vibration damping device. This device had a structure in which an inner shaft member and an outer cylinder member were connected by a main rubber elastomer. This device utilized the flow of fluid sealed inside to dampen input vibrations between the inner shaft member and the outer cylinder member. Such fluid-sealed vibration damping devices were not limited to, for example, vehicle engine mounts, but could also be widely used in cab mounts, differential mounts, suspension mounts, vibration damping bushings, etc.

[0003] However, the vibration damping characteristics required by the vibration damping device vary depending on the input vibration, the vehicle's driving conditions, etc. Therefore, it is preferable to have vibration damping characteristics that can be obtained by externally controlling the flow of fluid.

[0004] Therefore, Japanese Patent Application Publication No. 3-009139 (Patent Document 1) discloses an electroviscous fluid-encapsulated vibration damping device that uses an electroviscous fluid whose viscosity changes with the application of electricity. By controlling the energization of the electroviscous fluid, the vibration damping characteristics can be switched. However, in the vibration damping device described in Patent Document 1, it is also necessary to place the electrode for energizing in contact with the electroviscous fluid inside, and to supply power to the electrode from the outside, thus making the construction and manufacturing process complex.

[0005] On the other hand, German Patent Application Publication No. 102011117749 (Patent Document 2) discloses a vibration damping device using a magnetoviscous fluid whose viscosity varies according to the strength of the applied magnetic field. Since the magnetoviscous fluid can be controlled by applying a magnetic field from outside the fluid chamber, it eliminates the need for placing electrodes for energizing within the fluid chamber, as is done with electroviscous fluids. This also simplifies the manufacturing process of the vibration damping device compared to enclosed electroviscous fluids.

[0006] Existing technical documents

[0007] Patent documents

[0008] Patent Document 1: Japanese Patent Application Publication No. 3-009139

[0009] Patent Document 2: German Patent Application Publication No. 102011117749 Summary of the Invention

[0010] The problem that the invention aims to solve

[0011] However, when the magnetic field generating unit that applies the magnetic field to the magnetic viscous fluid is located outside the fluid chamber, it is difficult to apply the magnetic field generated by the magnetic field generating unit to the magnetic viscous fluid efficiently.

[0012] Specifically, for example, patent document 2 Figure 2 , Figure 3 As shown, it is also possible to assemble the magnetic field generating unit onto the outer circumferential surface of the outer cylinder component in an outer sleeve state. However, this does not take into account how to efficiently apply the magnetic field generated by the aforementioned magnetic field generating unit to the throttling path of the magnetoviscous fluid sealed in the fluid chamber. Therefore, there are problems such as the inability to fully utilize the vibration damping characteristics as the target, or the excessive magnetic field generating capacity required of the magnetic field generating unit, resulting in poor energy efficiency.

[0013] The problem solved by the present invention is to provide a novel vibration damping device that enables the magnetic field from the magnetic field generating unit to act efficiently on the magnetic viscous fluid sealed in the fluid chamber, thereby enabling the switching of vibration damping characteristics with good energy efficiency.

[0014] means for solving problems

[0015] Hereinafter, preferred embodiments for mastering the present invention will be described. However, the embodiments described below are merely illustrative and can be appropriately combined with each other. Furthermore, the multiple constituent elements described in each embodiment can be identified and used as independently as possible, and can also be appropriately combined with any constituent element described in other embodiments. Therefore, the present invention is not limited to the embodiments described below, and various other embodiments can be implemented.

[0016] The first aspect of the present invention is as follows.

[0017] A vibration damping device, which is a fluid-sealed vibration damping device, wherein an inner shaft member and an intermediate cylinder member are connected by a main body rubber elastomer, an outer cylinder member is fixedly fitted onto the intermediate cylinder member, and a pocket-shaped portion disposed on the main body rubber elastomer and opening on the outer periphery of the intermediate cylinder member is covered by the outer cylinder member, thereby forming a plurality of fluid chambers separated in the circumferential direction, and a throttling passage connecting these plurality of fluid chambers is provided in the vibration damping device, wherein...

[0018] A magnetically functional fluid is sealed in the fluid chamber.

[0019] A magnetic field generating unit is provided outside the fluid chamber, which applies a magnetic field to the magnetically functional fluid flowing in the throttling path.

[0020] The outer cylinder component is made of a non-magnetic material.

[0021] The intermediate cylinder component is made of a strongly magnetic material.

[0022] In this intermediate cylinder component, a magnetic field-acting opening is provided at a position corresponding to the throttling path to which a magnetic field is applied to the magnetic functional fluid.

[0023] In the vibration damping device described in this method, the fluid sealed in the fluid chamber is a magnetically functional fluid, and its viscosity varies depending on the magnetic field applied from the magnetic field generating unit. Therefore, by controlling the magnetic field applied from the magnetic field generating unit according to input vibrations, for example, the characteristics of the vibration damping device can be changed, thereby obtaining good vibration damping performance.

[0024] In particular, in the vibration damping device of this method, since the outer cylinder component arranged to cover the outer periphery of the fluid chamber is made of a non-magnetic material, it is possible to prevent the magnetic field from the magnetic field generating unit from being blocked or reduced by the outer cylinder component, thereby enabling the magnetic field from the magnetic field generating unit to be applied efficiently to the magnetic functional fluid.

[0025] Furthermore, in this vibration damping device, an intermediate cylinder component made of a strongly magnetic material is used, and a magnetic field opening is provided in the intermediate cylinder component at a position corresponding to the throttling path. Therefore, the magnetic field from the magnetic field generating unit can be efficiently guided to the throttling path through the intermediate cylinder component. That is, for example, the magnetic field from the magnetic field generating unit can be efficiently guided to the vicinity of the throttling path through the intermediate cylinder component, and the magnetic field opening is used to make the guided magnetic field act from the intermediate cylinder component toward the throttling path. In addition, even when, for example, a magnetic flux concentrating component described later is configured to increase the concentration of magnetic flux toward the formation site of the throttling path, the magnetic field opening can be used to prevent or reduce the escape of concentrated magnetic flux through the intermediate cylinder component, thus also facilitating the concentration of magnetic flux toward the throttling path.

[0026] Thus, in this vibration damping device, the intermediate cylinder component, which is used to fix the outer cylinder component to the outer peripheral surface of the main rubber elastomer and ensure the liquid tightness of the fluid chamber, enables the magnetic flux from the magnetic field generating unit to act efficiently on the magnetic functional fluid in the throttling path. As a result, a new vibration damping device is achieved that can switch vibration damping characteristics with good energy efficiency.

[0027] The second aspect of the present invention is based on the vibration damping device described in the first aspect above.

[0028] The intermediate cylinder component has:

[0029] A pair of axially oriented lateral portions, which are formed as a large-diameter cylindrical shape that is continuous in the circumferential direction; and

[0030] A groove-shaped axial middle portion, which is partially provided in the circumferential direction and extends circumferentially between these pair of axial side portions,

[0031] An opening for the magnetic field is provided in the middle part of the axial direction.

[0032] In the vibration damping device involved in this method, by utilizing the groove-shaped axial intermediate portion provided in the intermediate cylinder member, a throttling passage can be formed in the internal space of the groove. For example, the axial intermediate portion of the intermediate cylinder member can also be used to suppress the deformation of the throttling passage caused by the deformation of the main rubber elastomer due to input vibration.

[0033] The third aspect of the present invention is based on the vibration damping device described in the second aspect above.

[0034] The intermediate cylinder component is a single component formed by connecting the two axially opposite portions at the axially intermediate portion.

[0035] The magnetic field opening is formed by a window that extends through the bottom of the groove in the axially recessed middle portion.

[0036] In the vibration damping device involved in this method, a magnetic field opening can be provided on the intermediate cylinder component, and the intermediate cylinder component can be made into a single component, thereby enabling component management and facilitating the manufacturing of the vibration damping device.

[0037] The fourth aspect of the present invention is based on the vibration damping device described in the second aspect above.

[0038] The intermediate cylinder component is divided into two sections on both sides of its axial middle portion, and the pair of axial side portions are independent components.

[0039] The magnetic field-acting opening is formed between the axially separated segments in the middle of the axial section.

[0040] In the vibration damping device described in this method, since the intermediate cylinder member is separated from each other on both sides axially by the opening of the magnetic field, the intermediate cylinder member is also substantially disconnected axially around the opening of the magnetic field. Therefore, it is also possible to suppress, for example, the escape of magnetic flux acting on the throttling path due to the formation of a magnetic circuit in the continuous portion around the opening of the magnetic field in the intermediate cylinder member.

[0041] The fifth aspect of the present invention is based on the vibration damping device described in any of the first to fourth aspects described above.

[0042] The magnetic field generating unit is disposed on the outer periphery of the outer cylinder component.

[0043] In the vibration damping device described in this method, the arrangement space of the magnetic field generating unit can avoid affecting the fluid chamber, the main rubber elastomer, etc., and the arrangement space of the magnetic field generating unit can be set with a relatively large degree of freedom on the outer periphery of the outer cylinder member. In particular, in this method, by making the outer cylinder member into a non-magnetic material, for example by forming a throttling path extending along the inner periphery of the outer cylinder member, the magnetic field from the magnetic field generating unit arranged on the outer periphery of the outer cylinder member can also act efficiently on the throttling path.

[0044] The sixth aspect of the present invention is based on the vibration damping device described in any of the first to fifth aspects above.

[0045] In the throttling flow path, a magnetic flux concentrating member made of a strong magnetic material is disposed opposite each other in the width direction of the throttling flow path, and the magnetic field action opening in the intermediate cylinder member is disposed at a position corresponding to the opposite part in the magnetic flux concentrating member.

[0046] In the vibration damping device involved in this method, by arranging a magnetic flux concentration component at the forming part of the throttling path, it is possible to further concentrate the magnetic flux acting on the throttling path.

[0047] The seventh aspect of the present invention is based on the vibration damping device described in the sixth aspect above.

[0048] Between the intermediate sleeve and the outer cylinder member, a throttling member for forming the throttling path is arranged to extend circumferentially from the opening of the pocket-shaped portion provided in the main body rubber elastomer.

[0049] The throttling component is made of a strongly magnetic material.

[0050] The flux concentration member disposed opposite each other in the width direction of the throttling path is composed of the throttling member.

[0051] In the vibration damping device described in this method, the throttling member extending to the opening of the pocket-shaped portion can greatly ensure design freedom, such as the length of the throttling path. Furthermore, the throttling member can also be used to efficiently apply magnetic flux to the magnetically functional fluid within the throttling path.

[0052] The eighth aspect of the present invention is based on the vibration damping device described in any of the first to seventh aspects.

[0053] The magnetic field generating unit includes:

[0054] A coil component that generates a magnetic field when energized; and

[0055] A magnetic yoke component that guides the magnetic flux in the magnetic field generated by the coil component into the throttling path.

[0056] In the vibration damping device involved in this method, the magnetic flux from the coil member for generating the magnetic field can be efficiently guided to the magnetic functional fluid in the throttling path via the magnetic yoke member. Furthermore, by controlling the energization to the coil member, the magnetic flux density acting on the magnetic functional fluid and the vibration damping characteristics it exhibits can be easily controlled.

[0057] Furthermore, in this approach, the magnetic yoke component can be constructed either partially or entirely using, for example, an intermediate sleeve, or using, for example, a flux-concentrating component as described in the sixth or seventh approach above. Thus, the magnetic yoke component can be constructed with a smaller number of parts and a simpler structure.

[0058] Invention Effects

[0059] According to the present invention, in a vibration damping device that can change its vibration damping characteristics by controlling the magnetic field applied to the magnetic viscous fluid sealed in the fluid chamber from a magnetic field generating unit located outside the fluid chamber, the magnetic field from the magnetic field generating unit can be made to act efficiently on the magnetic viscous fluid sealed in the fluid chamber. As a result, a vibration damping device with a new structure that can switch its vibration damping characteristics with good energy efficiency can be realized. Attached Figure Description

[0060] Figure 1 This is a cross-sectional view showing the engine bracket as a first embodiment of the present invention, which is equivalent to... Figure 2 Diagram of section II.

[0061] Figure 2 yes Figure 1 Sectional view II-II.

[0062] Figure 3 In the formation Figure 1 The image shows a perspective view of the engine mount's main body after removing the outer cylinder component.

[0063] Figure 4 It indicates composition Figure 1 The diagram shows the middle sleeve of the engine mount. Figure 4 (a) in the figure is a 3D diagram. Figure 4 (b) in the image is the front view. Figure 4 (c) in the diagram is a longitudinal sectional view.

[0064] Figure 5 This is a cross-sectional view showing the engine bracket as a second embodiment of the present invention, which is equivalent to... Figure 6 A diagram of section IV-IV.

[0065] Figure 6 yes Figure 5 Sectional view VI-VI.

[0066] Figure 7 In the formation Figure 5 The image shows a perspective view of the engine mount's main body after removing the outer cylinder component.

[0067] Figure 8 It constitutes Figure 5 A top view of the throttling component of the engine mount shown.

[0068] Figure 9 This is a cross-sectional view showing the engine bracket as a third embodiment of the present invention.

[0069] Figure 10 It constitutes Figure 9 A top view of the throttling component of the engine mount shown.

[0070] Figure 11 This is a cross-sectional view showing a portion of the engine bracket as part of the fourth embodiment of the present invention.

[0071] Figure 12 This diagram illustrates another embodiment of the intermediate sleeve that can be used in the first to fourth embodiments of the present invention. Figure 12 (a) in the figure is a 3D diagram. Figure 12 (b) in the image is the front view. Figure 12 (c) in the diagram is a longitudinal sectional view.

[0072] Figure 13 This diagram illustrates yet another embodiment of the intermediate sleeve that can be used in the first to fourth embodiments of the present invention. Figure 13 (a) in the figure is a 3D diagram. Figure 13 (b) in the image is the front view. Figure 13 (c) in the diagram is a longitudinal sectional view.

[0073] Figure 14 This diagram illustrates yet another embodiment of the intermediate sleeve that can be used in the first to fourth embodiments of the present invention. Figure 14 (a) in the figure is a 3D diagram. Figure 14 (b) in the image is the front view. Figure 14 (c) in the diagram is a longitudinal sectional view.

[0074] Explanation of reference numerals in the attached figures

[0075] 10: Engine mount (vibration damping device) (first embodiment);

[0076] 12: Main body of the support frame;

[0077] 14: Inner shaft components;

[0078] 16: Outer cylinder components;

[0079] 18: Main body rubber elastomer;

[0080] 20: Limiting components;

[0081] 22: Protrusion;

[0082] 24: Intermediate sleeve (intermediate cylinder component);

[0083] 26: Window area;

[0084] 28: Groove-shaped part;

[0085] 29: The two sides of the axial direction;

[0086] 30: Bottom wall section;

[0087] 32: The opening under the influence of a magnetic field;

[0088] 34: Pocket-shaped portion;

[0089] 36: Sealing rubber layer;

[0090] 38: Fluid chamber;

[0091] 39: Magnetic functional fluids;

[0092] 40: Streamline traffic flow;

[0093] 41: Throttling tank;

[0094] 42: Flux concentration component;

[0095] 44: Positioning protrusion;

[0096] 46: Cylindrical cover component;

[0097] 52, 54: Supporting elastic body;

[0098] 56: Magnetic field generating unit;

[0099] 58: Coil;

[0100] 60: Magnetic yoke component;

[0101] 62: Bollard;

[0102] 64: Connector;

[0103] 66: Terminal section;

[0104] 68: Power unit;

[0105] 70: Vehicle body;

[0106] 72: Assembly hole;

[0107] 80: Engine mount (vibration damping device) (Second embodiment);

[0108] 81: Streamline the flow of goods;

[0109] 82: Throttling component;

[0110] 84: Separating rubber;

[0111] 86: Wide protrusion;

[0112] 88: Continuous hole;

[0113] 90: Through hole;

[0114] 92: Bottom component;

[0115] 94: Flux Concentration Unit;

[0116] 100: Engine mount (vibration damping device) (third embodiment);

[0117] 102: Throttling component;

[0118] 104: Opposite planes;

[0119] 110: Engine mount (vibration damping device) (fourth embodiment);

[0120] 112: Streamline the flow of traffic;

[0121] 114: Flux concentration component;

[0122] 116: Magnetic pole face. Detailed Implementation

[0123] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

[0124] exist Figure 1 , Figure 2 In this paper, as a first embodiment of a vibration damping device employing the structure of the present invention, an engine mount 10 for a motor vehicle is shown. The engine mount 10 is a fluid-sealed vibration damping device, having a mount body 12 constructed by connecting an inner shaft member 14 and an outer cylinder member 16 using a main body rubber elastomer 18. Figure 3 The diagram shows the state after removing the outer cylinder member 16 from the support body 12. In the following description, axial direction generally refers to the direction along the central axis of the support. Figure 1 The left-right and up-down directions refer to the primary vibration input directions. Figure 2 The up and down directions in the middle.

[0125] The inner shaft member 14 is formed in the shape of a generally cylindrical shape with a small diameter and extends linearly in the axial direction. The material of the inner shaft member 14 is not particularly limited, and strong magnetic materials such as ferrous metals can also be used. However, if there are concerns about the adverse effects of the magnetic field generating unit (56) described later on the magnetic field, it is preferable to make it from a non-magnetic material such as stainless steel or aluminum alloy.

[0126] A limiting member 20 is fixed to the axial central portion of the inner shaft member 14. The limiting member 20 is generally formed in a ring shape and is fixed to the inner shaft member 14 in an outer sleeve state. Figure 2 As shown, the inner shaft member 14 has two protrusions 22, 22 protruding to both sides in the vertical direction. In addition, the limiting member 20 is not necessary, but when the limiting member 20 is used, in case of concerns about the adverse effects of the magnetic field generating unit (56) described later on the magnetic field, it is preferable to make the limiting member from a non-magnetic material such as synthetic resin, rubber elastomer, or aluminum alloy.

[0127] Additionally, an intermediate sleeve 24, serving as an intermediate cylinder member, is arranged around the inner shaft member 14. For example... Figure 4 As shown in the single figure, the intermediate sleeve 24 is formed into a generally cylindrical shape with a diameter larger than that of the inner shaft member 14, and is arranged in an outer sleeve state that is radially separated from the inner shaft member 14. In addition, the inner shaft member 14 and the intermediate sleeve 24 (and the outer cylinder member 16) may also be radially eccentric, but in this embodiment they are arranged on approximately the same central axis.

[0128] The intermediate sleeve 24 is formed of a strongly magnetic material, preferably an ferrous metal. Compared with the use of non-magnetic materials such as aluminum alloys, this ensures the strength characteristics of the intermediate sleeve 24 and facilitates reduction in manufacturing costs and ease of processing.

[0129] The intermediate sleeve 24 has windows 26, 26 at two circumferential locations. In this embodiment, the pair of windows 26, 26 are located in the vertical direction. Figure 1 The windows 26 are positioned opposite each other in the vertical direction. Each window 26 extends through the central portion of the intermediate sleeve 24 in the thickness direction, forming a generally rectangular shape that extends circumferentially with a specified width in the axial direction.

[0130] In the intermediate sleeve 24, a groove-shaped portion 28 extending circumferentially is provided between the two windows 26, 26. Figure 2 They are positioned opposite each other in the left and right directions. Each groove-shaped portion 28 is a small-diameter groove-shaped portion formed in the axial middle part of the intermediate sleeve 24 and formed to open on the outer peripheral surface. It extends along the circumference of the intermediate sleeve 24, and its two ends in the circumference reach one of the two window portions 26, 26.

[0131] In summary, the intermediate sleeve 24 has a pair of axial side portions 29, 29 formed as a large-diameter cylindrical shape that is continuous in the circumferential direction, and the axial intermediate portion integrally has a groove-shaped portion 28, 28 that is partially provided in the circumferential direction and extends circumferentially between the pair of axial side portions 29, 29 and is connected thereto.

[0132] Furthermore, in the intermediate sleeve 24, the magnetic field opening 32 is formed in the bottom wall portion 30 of each groove 28 constituting the axial intermediate portion as a through hole extending through both the inside and outside. In this embodiment, the magnetic field opening 32 is formed in a generally rectangular shape in the central portion of the bottom wall portion 30, while the bottom wall portion 30 of each groove 28 is retained as a surrounding rectangular frame.

[0133] Furthermore, the aforementioned inner shaft member 14 and intermediate sleeve 24 are connected by a main rubber elastomer 18. The main rubber elastomer 18 is a thick-walled, generally cylindrical shape, with its inner circumferential portion fixed to the inner shaft member 14 and its outer circumferential portion fixed to the intermediate sleeve 24. Additionally, the main rubber elastomer 18 is drawn around the inner surface of the groove in the groove-shaped portion 28 by the magnetic field acting on the opening 32 of the intermediate sleeve 24, and is also fixed to the outer circumferential surface of the intermediate sleeve 24 at the groove-shaped portion 28. Such a main rubber elastomer 18 can be formed as an integrally vulcanized molded part comprising the inner shaft member 14 and the intermediate sleeve 24.

[0134] In addition, such as Figure 2 As shown, the main body rubber elastomer 18 has two pocket-shaped portions 34, 34. The pocket-shaped portions 34, 34 are respectively formed as recesses or indentations opening on the outer peripheral surface of the main body rubber elastomer 18, and in this embodiment, they open in the vertical direction. A pair of pocket-shaped portions 34, 34 are positioned corresponding to a pair of windows 26, 26 of the intermediate sleeve 24. The peripheral openings of the pocket-shaped portions 34, 34 are fixed to the opening frames of the windows 26, 26, and each pocket-shaped portion 34 opens outwards through each window 26. Furthermore, at approximately the center of the bottom of each pocket-shaped portion 34, 34, the protrusions 22, 22 of the limiting member 20 protrude at a height approximately at the midpoint of the depth direction of the pocket-shaped portions 34, 34.

[0135] Furthermore, an outer cylinder member 16 is fitted over the integrally vulcanized molded part of the main rubber elastomer 18. The outer cylinder member 16 is assembled by being externally fixed to the intermediate sleeve 24. The outer cylinder member 16 is formed into a generally cylindrical shape with a diameter larger than that of the inner shaft member 14. The outer cylinder member 16 is formed of a non-magnetic material, such as stainless steel, aluminum alloy, etc.

[0136] In this embodiment, the entire inner circumferential surface of the outer cylinder member 16 is covered by a thin-walled sealing rubber layer 36. Furthermore, the outer cylinder member 16 is fitted and fixed to the intermediate sleeve 24 by a diameter reduction process, such as octagonal diameter reduction. Additionally, the outer cylinder member 16 and the intermediate sleeve 24 are fluid-tightly sealed by the sealing rubber layer 36 sandwiched between them.

[0137] Thus, the support body 12 is formed by fitting the outer cylinder component 16 into the outer peripheral surface of the integrally vulcanized part of the main body rubber elastomer 18, which includes the inner shaft component 14 and the intermediate sleeve 24. A fluid-sealing area is formed inside the support body 12, which is fluid-sealed relative to the external space.

[0138] The fluid-sealing area includes two fluid chambers 38, 38 formed by covering a pair of pocket-shaped portions 34, 34 of the main body rubber elastomer 18 with the outer cylinder member 16. These fluid chambers 38, 38 are separated from each other in the circumferential direction. In this embodiment, a pair of fluid chambers 38, 38 are arranged on both sides in the vertical direction, separated by the inner shaft member 14.

[0139] Furthermore, the partition wall between the two fluid chambers 38, 38 in the circumferential direction and the walls on both sides of each fluid chamber 38 in the axial direction are all made of the main rubber elastomer 18. Moreover, in Figure 1 When vibration is input in the vertical direction, the main rubber elastomer 18 elastically deforms as the inner shaft member 14 and the outer cylinder member 16 displace relative to each other in a direction perpendicular to the axis, causing relative pressure fluctuations between the two fluid chambers 38, 38. Furthermore, in each fluid chamber 38, the protrusion 22 of the limiting member 20 protrudes radially from the inner side to the outer side, with the front end face of the protrusion 22 facing the outer cylinder member 16 at a predetermined distance. This constitutes a limiting mechanism that restricts the amount of elastic deformation of the main rubber elastomer 18 during vibration input by the contact between each protrusion 22 and the outer cylinder member 16.

[0140] A magnetically functional fluid 39 is sealed within a fluid-sealing region comprising a pair of fluid chambers 38, 38. The magnetically functional fluid 39 can be any fluid whose viscosity changes due to the action of a magnetic field. For example, the magnetically functional fluid 39 can be any of a magneto-rheological fluid (MRF), a magnetic fluid (MF), or a magnetic composite fluid (MCF) formed by mixing a magneto-rheological fluid and a magnetic fluid. Preferably, the magnetically functional fluid 39 is a fluid whose viscosity changes significantly with respect to the change in magnetic flux density of the applied magnetic field; however, a magnetic composite fluid in which the increase in viscosity can be easily adjusted according to the mixing ratio of the magneto-rheological fluid and the magnetic fluid can also be used.

[0141] As the magnetic functional fluid 39, for example, a suspension or colloidal solution in which strongly magnetic particles are dispersed in a base liquid such as water or oil can be used, wherein the surface of the strongly magnetic particles is covered with a surfactant, making it difficult for the strongly magnetic particles to aggregate or settle in the base liquid. Alternatively, it is preferable to prevent or reduce aggregation by dispersing the strongly magnetic particles in a base liquid in which a surfactant has been added.

[0142] The strongly magnetic particles are, for example, metallic particles such as iron, ferrite, and magnetite (magnet), preferably with a particle size of about 8 nm to 10 μm. The base liquid is not particularly limited as long as it can disperse the strongly magnetic particles; for example, water, isoparaffins, alkylnaphthalenes, perfluoropolyethers, polyolefins, and silicone oils can be used. Furthermore, it is preferred that the base liquid is an incompressible fluid. The surfactant is appropriately selected depending on the base liquid; for example, oleic acid is preferred. In addition, the main difference between magnetoviscous fluids and magnetic fluids lies in the particle size of the strongly magnetic particles; the particle size of the strongly magnetic particles in magnetoviscous fluids is larger than that in magnetic fluids.

[0143] However, the description of the above-mentioned magnetic functional fluid is a description of a preferred example of magnetic functional fluid 39, and as mentioned above, it should not be interpreted in a limiting way as to the magnetic functional fluids that can be used in the present invention.

[0144] Fluid chambers 38, 38 containing such magnetically functional fluid 39 are interconnected via throttling passages 40, 40 that constitute the fluid-sealing region. Each throttling passage 40 extends circumferentially from both ends of each fluid chamber 38, connecting a pair of fluid chambers 38, 38 to each other.

[0145] In this embodiment, in a pair of grooves 28, 28 of the intermediate sleeve 24, a throttling groove 41 is formed in the main body rubber elastomer 18 filling each groove 28. The throttling groove 41 is covered by the outer cylinder member 16, thereby forming a throttling path 40. The throttling groove 41 extends along the entire circumferential length of each groove 28 of the intermediate sleeve 24 with a substantially constant cross-sectional shape.

[0146] Furthermore, each throttling groove 41 houses a flux concentrating member 42 made of a strongly magnetic material such as iron. In this embodiment, a pair of flux concentrating members 42 are assembled at the ends of both sides of the throttling groove 41 in the groove width direction (support axial direction). This pair of flux concentrating members 42, 42 extends circumferentially in an arc shape with a generally constant rectangular cross-section, is embedded in both sides of the throttling groove 41 in the groove width direction, and is positioned and fixed within the throttling groove 41 by pressing the outer circumferential surface with the outer cylinder member 16. As a result, flux concentrating members 42, 42 are arranged in a filled state along the entire length of both sides of the throttling groove 41 in the groove width direction, and a throttling flow path 40 that allows fluid flow between a pair of fluid chambers 38, 38 is formed between the opposing surfaces of the pair of flux concentrating members 42, 42.

[0147] Furthermore, in this embodiment, the positioning protrusion 44, located at the center of the throttling groove 41 in the groove width direction, protruding from the bottom surface of the groove and extending circumferentially, is formed by the main body rubber elastomer 18 wound into the groove of the throttling groove 41. This positioning protrusion 44 is embedded between the opposing surfaces of a pair of flux concentrating members 42, 42, thereby enabling high-precision and stable setting of the dimensions between the opposing surfaces of the pair of flux concentrating members 42, 42 and the flow path cross-sectional area of ​​the throttling path 40. Furthermore, the flux concentrating members 42, 42 may also be interconnected by non-magnetic materials, or positioned by bonding to a rubber elastomer, etc., and the positioning protrusion 44 is not essential.

[0148] Furthermore, a cylindrical cover member 46 is installed on the support body 12 in an outer sleeve state, and the outer cylindrical member 16 and the cylindrical cover member 46 constitute the housing for the magnetic field generating unit. In addition, the cylindrical cover member 46 is formed into a generally cylindrical shape with a diameter larger than that of the outer cylindrical member 16. There is no limitation on the material, but it is preferable to use a metal material with high strength and rigidity.

[0149] Furthermore, a magnetic field generating unit 56 is assembled between the outer cylinder member 16 and the cylindrical cover member 46, which are positioned to each other in the axial and radial directions, and is positioned by the supported elastic bodies 52 and 54.

[0150] The magnetic field generating unit 56 is generally formed in a circular shape, with a yoke member 60 assembled around the coil 58. The coil 58 generates a magnetic field by being energized, and conventionally known coils can be used. Typically, it is formed by winding an insulated conductive wire around a spool, and the entire coil is coated with an insulating resin as needed. In this embodiment, for example, a large-diameter hollow coil structure with a conductive wire wound circumferentially along the outer peripheral surface of the outer cylinder member 16 can be used. The two ends of the conductive wire of the coil 58 are axially extended at one point on the circumference and connected to the terminal portion 66 of the connector 64, and electrically connected to an external energizing control device (not shown) via the connector 64.

[0151] The yoke member 60 is formed of a strongly magnetic material such as iron. The yoke member 60 has a U-shaped cross-section that opens towards the inner periphery, and is arranged to cover the axial end faces and outer periphery of the coil 58. Furthermore, the open end face on the inner periphery side of the yoke member 60 is assembled in a state of contact or proximity to the outer periphery of the outer cylinder member 16. The axial end faces and outer periphery of the yoke member 60 are positioned and fixedly supported relative to the housing of the magnetic field generating unit, which is composed of the outer cylinder member 16 and the cylindrical cover member 46, via supporting elastic bodies 52 and 54.

[0152] Thus, the magnetic flux generated by energizing the coil 58 is guided to the yoke member 60, which is a strongly magnetic body, thereby suppressing magnetic flux leakage to the axial outer and peripheral sides. Furthermore, the magnetic flux guided by the yoke member 60 is released from the open ends on both sides of the axial direction on the inner peripheral side of the yoke member 60 to the outside of the yoke member 60. However, on the inner peripheral side of the yoke member 60, the magnetic flux concentrating members 42, 42, and the intermediate sleeve 24, made of strongly magnetic material, are positioned relatively close to each other, separated by the outer cylinder member 16, made of non-magnetic material, and the sealing rubber layer 36. Therefore, the magnetic flux generated by energizing the coil 58 is introduced from the inner peripheral side of the yoke member 60 into the magnetic flux concentrating members 42, 42, and the intermediate sleeve 24, forming a magnetic circuit on the inner peripheral side of the coil 58.

[0153] Here, the flux concentrating members 42, 42 forming the magnetic circuit are disconnected by the throttling passage 40, and the axially opposing surfaces of the pair of flux concentrating members 42, 42 constitute magnetic pole faces opposing each other on the magnetic circuit across the throttling passage 40. Furthermore, in the intermediate sleeve 24, the magnetic circuit is also disconnected at the opening 32, which is also affected by the magnetic field, at a position corresponding to the throttling passage 40. Therefore, it is possible to prevent the magnetic poles acting on the axially opposing surfaces of the flux concentrating members 42, 42, which are magnetic pole faces, from escaping into the intermediate sleeve 24. Moreover, even if there is magnetic flux guided from the yoke member 60 to the intermediate sleeve 24, since the magnetic reluctance on the intermediate sleeve 24 increases at the opening 32, it is easily guided to the flux concentrating members 42, 42. As a result, it is possible to increase the magnetic flux density between the axially opposing surfaces of the flux concentrating members 42, 42, which constitute magnetic pole faces opposing each other across the throttling passage 40.

[0154] Furthermore, the intermediate sleeve 24 has cylindrical axial side portions 29, 29, which are integrally connected to form a groove-shaped portion 28. Therefore, the magnetic flux emitted circumferentially from the open ends on both sides of the magnetic yoke member 60 is also captured by the axial side portions 29, 29 and guided from the groove-shaped portion 28 to the throttling passage 40 between the opposing surfaces of the magnetic flux concentrating members 42, 42, which also enables the magnetic force to act more efficiently on the magnetic functional fluid 39.

[0155] Thus, in the engine mount 10 of this embodiment, the magnetic flux generated by energizing the coil 58 is concentrated on the throttling passage 40, and a large magnetic force can be applied to the magnetically functional fluid 39 flowing in the throttling passage 40. In short, the magnetic energy acting on the magnetically functional fluid 39 in the throttling passage 40 can be obtained efficiently relative to the power supply energy to the magnetic field generating unit 56.

[0156] Furthermore, the specific shape of the throttling path 40, such as its cross-sectional area and length, can be appropriately adjusted in a way that achieves the fluid flow characteristics corresponding to the required vibration damping performance, and is not limited to this.

[0157] Furthermore, as shown in this embodiment, the throttling path 40 is formed along its entire length between the opposing surfaces of the flux concentrating members 42, 42, thereby increasing the magnetic force on the magnetically functional fluid 39 within the throttling path 40, but this is not a limitation. For example, the flux concentrating members 42, 42 may be arranged locally along the length of the throttling path 40. In addition to using the flux concentrating members 42, 42 to form the entire surface of each pair of opposing surfaces in the cross-section of the throttling path 40, the flux concentrating members 42, 42 may also be used to partially form a pair of opposing surfaces in the cross-section of the throttling path 40.

[0158] Furthermore, from the viewpoints of magnetic flux concentration and reduction of magnetic reluctance on the magnetic circuit, it is preferable that the axially outer end of each flux concentration member 42 is close to the opening end of the corresponding axially inner circumferential side of the yoke member 60. For example, each flux concentration member 42 may be configured such that at least a portion of the opening ends of the yoke member 60 overlap in the radial projection. In addition, in this embodiment, the axially outer end of each flux concentration member 42 is separated from the opening ends of the yoke member 60 in the axial direction, and the two members do not overlap in the radial projection, but it is preferable to reduce the axial separation amount: D, and the opening width relative to the inner circumferential side of the yoke member 60: B, preferably D≤(2 / 3)B.

[0159] In addition, the magnetic circuit disconnection part in the magnetic field generated by the magnetic field generating unit 56 is provided at the position corresponding to the throttling passage 40, thereby improving the magnetic field effect on the magnetic functional fluid 39 in the throttling passage 40. In this respect, it can also be considered that the opposing surfaces between the magnetic flux concentrating members 42 and 42 are roughly the same as the magnetic field effect opening 32 of the intermediate sleeve 24.

[0160] Therefore, the magnetic field opening 32 of the intermediate sleeve 24 is located on the inner circumference of the throttling passage, and is formed at a position corresponding to the throttling passage in such a way that it overlaps with the throttling passage in radial projection. However, the size and shape of the magnetic field opening 32 are not particularly limited, but considering the rate of increase of magnetic flux acting on the throttling passage 40, it is preferable to make the axial width of the magnetic field opening 32 greater than the passage width of the throttling passage 40. In particular, in this embodiment where the throttling passage 40 is formed between the opposing surfaces of a pair of flux concentrating members 42, 42, considering the concentration of magnetic flux towards the flux concentrating members 42, 42, it is preferable to set the axial width of the magnetic field opening 32 to be larger than the distance between the opposing surfaces of the pair of flux concentrating members 42, 42.

[0161] Furthermore, considering the rate of increase of the magnetic flux acting on the throttling passage 40, the magnetic field opening 32 is preferably formed to have a length covering the entire length of the throttling passage 40 in the passage length direction (circumferential direction of the support in this embodiment). However, the magnetic field opening 32 may not necessarily cover the entire length of the throttling passage and may be provided partially. It is preferable to provide it covering more than half the length in the length direction of the throttling passage, more preferably covering more than 60% of the length, and even more preferably covering more than 80% of the length. In addition, in this embodiment, the magnetic field opening 32 is provided in the central portion excluding the two ends of the throttling passage, covering approximately 80% of the total length of the throttling passage.

[0162] Furthermore, in the axially adjacent portions of the magnetic field-acting opening 32, the intermediate sleeve 24 overlaps with the opening ends of the inner circumference of the yoke member 60 in its radial projection. Particularly in this embodiment, the axially adjacent portions 29, 29, which are formed as large diameters in the intermediate sleeve 24, are arranged to overlap with the opening ends of the inner circumference of the yoke member 60 in their radial projection at least in a portion (the inner axial ends). This also reduces the leakage magnetic flux released to the outside from the closed magnetic circuit (the magnetic circuit passing through the flux concentrating members 42, 42, the intermediate sleeve 24, and the throttling passage 40) of the yoke member 60.

[0163] The engine mount 10 of this embodiment, constructed as described above, is mounted to a vehicle, for example, by being mounted to a power unit 68, which serves as a member connected to the inner shaft member 14 for vibration damping, and by a cylindrical cover member 46, which is fixed to the outer cylinder member 16, being mounted to a vehicle body 70, which serves as a member connected to the other side for vibration damping. The cylindrical cover member 46 is fixed to the vehicle body 70, for example, by pressing it into a mounting hole 72 in the vehicle body 70. Furthermore, the inner shaft member 14 can also be mounted to the power unit 68 via an inner bracket (not shown). Similarly, the cylindrical cover member 46 can also be mounted to the vehicle body 70 via an outer bracket (not shown).

[0164] When the engine mount 10 is installed in the vehicle as shown, when vibrations in the vertical direction of the opposing fluid chambers 38, 38 are input to the engine mount 10, a flow of sealed fluid (magnetic functional fluid 39) is generated between the fluid chambers 38, 38 through the throttling passage 40, thereby exerting a vibration damping effect based on the fluid flow.

[0165] The engine mount 10 controls the viscosity of the magnetic functional fluid 39 by using a magnetic field generating unit 56 to control the energization of a coil 58 with a magnetic field acting on the magnetic functional fluid 39, which is a sealing fluid, flowing in the throttling passage 40. In particular, in the magnetic field generating unit 56, a magnetic field is formed around the coil 58 by energizing the coil 58 and acting on the mount body 12 through the magnetic yoke member 60. As described above, the magnetic flux concentrating members 42, 42, arranged at positions corresponding to the throttling passage 40 and the intermediate sleeve 24 having a magnetic field action opening 32 act efficiently and concentratedly on the magnetic functional fluid 39 in the throttling passage 40.

[0166] Furthermore, the viscosity of the magnetic functional fluid 39 varies depending on the strength of the applied magnetic field. Therefore, the viscosity of the magnetic functional fluid 39 within the throttling passage 40 can be controlled, for example, by switching the power supply to the coil 58 on / off, or by adjusting the power supply in stages or continuously. This controls the flow characteristics of the magnetic functional fluid 39 through the throttling passage 40, thereby enabling switching control of the performance (vibration damping characteristics) of the engine mount 10. The switching method for the performance of the engine mount 10 is not particularly limited; the performance can be switched in stages or continuously in multiple ways to meet the required vibration damping performance.

[0167] In particular, in this embodiment, as described above, the magnetic energy of the magnetic functional fluid 39 acting on the throttling path 40 can be obtained efficiently relative to the power supply energy to the magnetic field generating unit 56. Therefore, it is easy to achieve a large characteristic change by switching control of the vibration damping characteristics of the engine mount 10 with excellent energy efficiency.

[0168] Furthermore, in the engine bracket 10 of this embodiment, the magnetic field generating unit 56 is disposed off the fluid sealing region on the outer periphery of the outer cylinder member 16 and is formed with a different structure from the bracket body 12. Therefore, the structure including the magnetic field generating unit 56 can be simplified, and an energized structure for energizing the magnetic field generating unit 56 can be formed independently from the bracket body 12, thereby facilitating manufacturing, management, etc.

[0169] exist Figures 5-6In this paper, as a second embodiment of the fluid-sealed vibration damping device employing the structure of the present invention, an engine mount 80 for a motor vehicle is shown. The engine mount 80 of this embodiment illustrates a different configuration from the first embodiment in terms of the throttling path construction and path length. For components and parts substantially the same as those in the first embodiment, the same reference numerals are used in the figures, and therefore descriptions are omitted.

[0170] According to the diagram, the support body 12, excluding the outer cylinder component 16, is... Figure 7 It is also known that the engine bracket 80 of this embodiment has a pair of throttling members 82, 82 that are connected in series in the circumferential direction to form a throttling passage 81 that is longer in the circumferential direction. The pair of throttling members 82, 82 are used instead of each pair of magnetic flux concentrating members 42, 42 in the engine bracket 10 of the first embodiment.

[0171] That is, each throttling member 82 is made of the same material (strong magnetic material) as the flux concentrating member of the first embodiment, and is generally formed into a semi-cylindrical shape with a circumferential length of slightly less than half a circumference. Moreover, a pair of throttling members 82, 82 are joined at one end in the circumferential direction and assembled into an integral vulcanized part of the main rubber elastomer 18 with a length of less than one circumference in the outer circumferential portion.

[0172] In this assembled state, the circumferential end of one of the mating throttling members 82, 82 is embedded in one of the intermediate sleeves 24. Figure 6 The groove-shaped portion 28 (on the right side of the middle sleeve). The circumferential ends of the pair of throttling members 82, 82 are each embedded in the other side of the intermediate sleeve 24. Figure 6 The circumferential end of the groove-shaped portion 28 (on the left side of the middle sleeve 24). Furthermore, on the other side of the groove-shaped portion 28 of the middle sleeve 24, a separating rubber 84 is formed protruding along the entire length of the groove width in the circumferential middle portion. Moreover, by positioning the other circumferential end of each of the pair of throttling members 82, 82 on both sides circumferentially clamping the separating rubber 84, the other circumferential end of each of the pair of throttling members 82, 82 is held in a mating state.

[0173] In addition, such as Figure 8 As shown, each throttling component 82 has a wide protrusion 86, 86 protruding in width dimension (axial dimension of the bracket) in the middle part of the circumferential direction, and the middle part of the circumferential direction is larger than the two sides of the circumferential direction.

[0174] Furthermore, each throttling member 82 has a continuous hole 88 extending circumferentially from one end of the interlocking members to the vicinity of the other end. Further, at the other end of the throttling member 82, a broad, generally rectangular through-hole 90 is formed through both the inner and outer surfaces, with the end of the continuous hole 88 opening into the through-hole 90. Additionally, the opening on the inner circumferential side of the continuous hole 88 is fluid-tightly sealed by a bottom member 92 made of a non-magnetic material such as a rubber elastomer or synthetic resin, thus forming a substantially grooved structure.

[0175] In this embodiment, a pair of throttling members 82, 82 are embedded in the grooves 28, 28 of the intermediate sleeve 24, replacing the flux concentrating members 42, 42 in the first embodiment described above. Thus, the continuous holes 88, 88 of the pair of throttling members 82, 82 are connected in series in the circumferential direction, forming a throttling passage 81 extending circumferentially at a length of more than half a circumference on the inner circumferential surface of the outer cylinder member 16. Furthermore, the two circumferential ends of the throttling passage 81 communicate with the fluid chamber 38 of each throttling member 82 through through holes 90 formed in each of the throttling members 82.

[0176] As described above, in the engine bracket 80 of this embodiment, the throttling member 82, which is composed of a single component, is interrupted on both sides of the throttling passage 81 by a continuous hole 88 in the axial direction (throttling width direction), thereby forming a pair of magnetic flux concentration sections 94, 94 that are axially spaced apart by a predetermined distance. Moreover, the throttling passage 81 is formed between the opposing surfaces of the pair of magnetic flux concentration sections 94, 94, which are made of a strongly magnetic material.

[0177] Therefore, in the engine mount 80 of this embodiment, similarly to the engine mount of the first embodiment, the viscosity of the magnetic functional fluid 39 can be efficiently controlled by the magnetic force from the magnetic field generating unit 56, and the switching control of the anti-vibration characteristics based on the fluid flow effect through the throttling path 81 can be achieved with excellent energy efficiency.

[0178] In particular, in this embodiment, since a throttling flow path 81 with a longer path length than the throttling flow path 40 in the first embodiment is realized, the tuning freedom of the throttling flow path 81 can be increased. Furthermore, by making the magnetic field generated by the annular magnetic field generating unit 56 act on the magnetic functional fluid 39 in the throttling flow path 81 over a wider range in the circumferential direction, the vibration damping characteristics can be varied more greatly.

[0179] In addition, in this embodiment, in the wide protrusions 86, 86 formed in the throttling member 82, a pair of flux concentration sections 94, 94 are arranged to overlap in radial projection with respect to the opening ends of the inner peripheral side of the yoke member 60. Therefore, leakage flux in the magnetic circuit is suppressed, and the magnetic field from the yoke member 60 can be applied more efficiently to the flux concentration sections 94, 94 and then to the magnetic functional fluid 39 in the throttling passage 81.

[0180] Furthermore, in the throttling member 82 of this embodiment, a single member structure is formed in which a pair of flux-concentrating portions 94, 94, which are interrupted by a continuous hole 88, are integrally continuous at the outer periphery of the through hole 90 at one end in the circumferential direction. However, for example, it can also be formed in a structure in which the pair of flux-concentrating portions 94, 94 are connected by the bottom member 92 as independent components. In this case, it is not necessary to provide the through hole 90, and it is also possible to avoid the reduction of the magnetic force acting on the magnetic functional fluid 39 in the throttling passage 82 caused by the flux winding around the continuous portion of the outer periphery of the through hole 90.

[0181] Furthermore, the shapes of the magnetic action surfaces of the magnetic functional fluid within the throttling path, namely the opposing surfaces of the pair of flux concentrating members 42, 42 in the first embodiment and the opposing surfaces of the pair of flux concentrating portions 94, 94 in the second embodiment, are not limited to parallel opposing planes as illustrated in the example.

[0182] For example, such as Figures 9-10 As illustrated in the engine bracket 100 of the third embodiment, non-parallel opposing surfaces can also be used in the pair of flux concentration sections 94, 94. Furthermore, in the engine bracket 100 of this embodiment, components and parts with substantially the same structure as those in the second embodiment are labeled with the same reference numerals as in the second embodiment, and detailed descriptions are omitted.

[0183] That is, the throttling member 102 in the engine bracket 100 of this embodiment is formed with a structure that is substantially the same as that of the throttling member 82 in the second embodiment, but the opposing surfaces 104, 104 of the pair of magnetic flux concentration portions 94, 94 that constitute the two side walls of the throttling passage 81 have non-parallel opposing surfaces, and the shape of the passage cross section of the throttling passage 81 is formed to be different from that of a rectangle.

[0184] In particular, in this embodiment, the opposing surfaces 104, 104 of the pair of flux concentration portions 94, 94 constituting the two side walls of the throttling passage 81 are formed as inclined surfaces that gradually separate from each other from the inner peripheral side toward the outer peripheral side. As a result, the cross-sectional shape of the passage of the throttling passage 81 is formed to be approximately trapezoidal.

[0185] Incidentally, if the distance between the opposing surfaces 104, 104 of the pair of flux concentration sections 94, 94 is made larger on the inner circumferential side than on the outer circumferential side, as in this embodiment, the magnetic flux acting between the pair of opposing surfaces 104, 104 can be easily guided to a position closer to the inner circumferential side than the outer circumferential side within the throttling passage 81, and a stronger magnetic field can be applied to the magnetic functional fluid flowing on the inner circumferential side within the throttling passage 112 than to the magnetic functional fluid flowing on the outer circumferential side.

[0186] In this way, by making the intensity of the magnetic field acting on the magnetic functional fluid within the throttling passage 112 different in the radial direction, the flow state of the magnetic functional fluid within the throttling passage 112 can be controlled, for example. Specifically, for example, if the viscosity of the magnetic functional fluid is made smaller in the outer peripheral portion of the throttling passage 112 where the flow path of the magnetic functional fluid is longer than that in the inner peripheral portion, it is also expected to suppress turbulence and other effects caused by the different flow paths within the throttling passage 112.

[0187] However, the shape of the cross-section of the throttling path 81 is not limited to the trapezoidal shape of this embodiment. For example, it is possible to tilt only one side of the path wall in the opposite direction, or to give the opposite surface 104 of the throttling path 81 a curved or arbitrary shape.

[0188] Furthermore, in the first to third embodiments described above, a throttling passage 40, 81, 102 extending linearly in the circumferential direction is formed within the groove 28 of the intermediate sleeve 24, including the length and cross-sectional area of ​​the throttling passage.

[0189] The specific form and structure are not limited. In addition, as mentioned above, the flux concentration component 5 disposed in the throttling path is not necessary in this invention, but the specific form, including the shape and size of the flux concentration component used, is not limited.

[0190] For example, such as Figure 11 As illustrated in the engine bracket 110 of the fourth embodiment, it can also be formed relative to the throttling groove 41 that extends circumferentially relative to the groove 28 formed in the intermediate sleeve 24.

[0191] Two throttling paths 112, 112 extend in roughly parallel directions. Furthermore, the engine mount 1100 of this embodiment illustrates a throttling structure differently from that of the first embodiment, while maintaining the same basic structure as the first embodiment.

[0192] Therefore, only a portion of the characteristic longitudinal section is shown, and in this figure, the same reference numerals are used to label the components and parts that are substantially the same as those in the first embodiment, thereby omitting detailed descriptions.

[0193] That is, in the engine bracket 110 of this embodiment, the flux concentrating member 114, which serves as the throttling member 5 forming the throttling path 112, is formed with a substantially constant cross-sectional shape (in this embodiment, a substantially rectangular cross-section).

[0194] The shape is a curved plate extending in an arc along the circumference. The flux concentrator 114 has approximately the same length dimension in the circumference as the throttling groove 41 formed in the groove-shaped portion 28 of the intermediate sleeve 24, and is arranged along the entire length of the throttling groove 41. Furthermore, the width dimension of the flux concentrator 114 (support)

[0195] The axial dimension is smaller than the width (inner dimension) of the throttling groove 41, and it is positioned at the center of the width direction of the throttling groove 41. Furthermore, the thickness dimension (radial dimension of the support) of the flux concentrator 114 is similar to that of the throttling groove 41.

[0196] Same or slightly larger.

[0197] Thus, the throttling slot 41 is divided in the slot width direction by the flux concentrator 114, forming a pair of throttling paths 112, 112 located on both sides of the flux concentrator 114 in the width direction and extending circumferentially.

[0198] In this pair of throttling paths 112, on the two opposing side walls along the support axis, only the wall located on the inner side of the support axis is composed of a flux concentration member 114, while the wall located on the outer side of the support axis is composed of a flux concentration member 114.

[0199] The side wall is composed of the main rubber elastomer 18 within the groove 28.

[0200] In this way, even if only one wall surface in the width direction of the throttling path 112 is composed of the flux concentrating member 114, the flux concentrating member that constitutes the magnetic path of the magnetic field generated by the magnetic field generating unit 56 can be utilized.

[0201] 114 achieves magnetic flux concentration, thereby forming magnetic pole surfaces 116, 116 on the 0 end faces exposed to the throttling passages 112, 112 in the magnetic flux concentration member 114. Therefore, magnetic force can be efficiently applied to the magnetically functional fluid 39 in each throttling passage 112, 112, achieving the same effect as the above-described embodiment.

[0202] In particular, in this embodiment, a middle sleeve 24 made of a strongly magnetic material is disposed on the outer side of the support, relative to the throttling passage 112 disposed on the inner side of the support axially relative to the flux concentrating member 114. Therefore, the concentration effect of the middle sleeve 24 on the magnetic flux of the magnetic functional fluid 39 in the throttling passage 112 can also be utilized, and it is also expected that the magnetic flux of the middle sleeve 24 and the flux concentrating member 114 will be concentrated relative to the magnetic functional fluid 39 disposed in the throttling passage 112 between the middle sleeve 24 and the flux concentrating member 114.

[0203] Furthermore, in the engine bracket 110 of this embodiment, in addition to the flux concentrating member 114 located in the central part of the bracket axial direction, flux concentrating members (42, 42) located at both ends of the bracket axial direction as shown in the first embodiment above may also be used in the throttling groove 41. Thus, each opposing inner surface of the two throttling paths 112, 112 is composed of flux concentrating members.

[0204] However, in the first to fourth embodiments described above, an intermediate sleeve 24 consisting of a single component formed by stamping or the like is used. It is also possible to form the intermediate sleeve 24 into two or more segmented structures. By employing a segmented intermediate sleeve 24, advantages in manufacturing and assembly can be enjoyed. For example, by dividing the intermediate sleeve at a position corresponding to the formation location of the throttling passage and separating it axially in the support, the reduction in magnetic flux acting on the throttling passage caused by the infiltration of magnetic flux through the intermediate sleeve can be suppressed.

[0205] Specifically, for example Figure 12 As illustrated in (a) to (c), the intermediate sleeve 24 can also be composed of a pair of segmented sleeves 24a, 24a, which are divided along a dividing line extending circumferentially from the axial center. Furthermore, in the accompanying drawings illustrating other embodiments of the intermediate sleeve 24 shown below, for ease of understanding, the same reference numerals are used for the same parts as in the above embodiments.

[0206] In each of the segmented sleeves 24a, approximately half of the axial length of the grooved portion 28 is integrally formed relative to the two axially opposite sides of the large-diameter cylindrical portion 29. Furthermore, a pair of segmented sleeves 24a, 24a are arranged on the outer peripheral surface of the main rubber elastomer in the illustrated state where they are spaced apart by a predetermined distance in the axial direction and the end faces of the grooved portions 28, 28 are axially opposed to each other.

[0207] In the dividing sleeves 24a, 24a, the magnetic field opening 32, which is the same as in the above embodiment, can be formed to span between the bottom wall portions 30a, 30a. However, in this embodiment, considering the strength, dimensional accuracy, and processing reasons of the dividing sleeves 24a, 24a, an independent magnetic field opening 32a, 32a is provided to pass through approximately the center of the bottom wall portions 30a, 30a.

[0208] Even when using a pair of axially divided sleeves 24a, 24a as the intermediate sleeve 24 in the above embodiments, the same effects as in the above embodiments can be achieved. In particular, since the axially separated portions of the divided sleeves 24a, 24a in this embodiment are configured separately from each other, compared with the case of using a single-piece divided sleeve 24, it is possible to suppress the escape (entry) of magnetic flux through the divided sleeves 24a, 24a outside the throttling path, and also to improve the concentration of magnetic flux into the magnetic functional fluid within the throttling path.

[0209] Furthermore, for example, can also be used. Figure 13 The pair of dividing sleeves 24b, 24b illustrated in (a) to (c) have a larger axial separation distance between them at the location corresponding to the throttling flow path.

[0210] In the intermediate sleeve 24 of this embodiment, in the bottom wall portion 30 of the groove 28 in the intermediate sleeve 24 of the first embodiment, the magnetic field action opening 32 can also be understood as having a predetermined size in the groove width direction (support axis) of the groove 28 and being formed with a length that covers the entire circumferential (groove length direction) of the groove 28.

[0211] By employing such dividing sleeves 24b, 24b, the separation distance between dividing sleeves 24b, 24b can be set to be more than... Figure 12 The large size of the segmented sleeves 24a and 24a shown allows for more efficient suppression of magnetic flux escape (winding in) through the segmented sleeves 24a and 24a outside the throttling path. Additionally, with... Figure 12 Compared to the segmented sleeve 24a shown, the number of components can be reduced to save materials, and it is not necessary to form the magnetic field opening 32a in each segmented sleeve 24a, thus making manufacturing easier.

[0212] Furthermore, for example, Figure 14As illustrated in (a) to (c), the intermediate sleeve 24 can also be composed of a pair of segmented sleeves 24c, 24c, each a semi-cylindrical shape, formed by dividing the radially opposing portions with dividing lines extending axially. In this embodiment, the intermediate sleeve 24 is formed as a pair of segmented sleeves 24c, 24c, on both sides of the radial direction orthogonal to the opposing directions of the grooved portions 28, 28, each divided by dividing lines extending axially. Further, in Figure 14 In the intermediate sleeves of methods (a) to (c), the intermediate sleeves are divided into two parts in the circumferential direction, but the intermediate sleeves can also be formed into a segmented structure that is divided into three or more parts in the circumferential direction.

[0213] The embodiments of the present invention have been described in detail above, but the present invention is not limited to this specific description. For example, multiple throttling paths may be provided, in which case it is sufficient to apply a magnetic field from the magnetic field generating unit to the magnetic functional fluid in at least one throttling path.

[0214] In the above embodiment, the throttling path 40 extends circumferentially as a whole, but the throttling path may also extend partially axially or radially. In this case, it is preferable that the magnetic field of the magnetic field generating unit acts on the magnetic functional fluid at the circumferentially extended portion of the throttling path.

[0215] In the above embodiment, the coil 58 is arranged around the entire circumference of the outer cylinder member 16 in an outer sleeve state, but the coil 58 does not necessarily need to be arranged coaxially with respect to the outer cylinder member 16. Specifically, for example, the coil may be arranged locally on the outer periphery of the outer cylinder member in the circumferential direction with the central axis of the coil located at a position closer to the outer periphery than the outer cylinder member. Thus, when the coil is energized, the position of the magnetic field relative to the magnetic functional fluid can be defined in the circumferential direction of the outer cylinder member.

[0216] In the above embodiment, both fluid chambers 38 and 38 are pressure chambers that generate internal pressure changes when vibration is input. However, for example, one of the fluid chambers may be formed as a balance chamber in which a portion of the wall is made of a flexible membrane. In addition, the number of fluid chambers is not limited to two, and a structure with three or more fluid chambers may be adopted.

Claims

1. A vibration damping device (10, 80, 100, 110), which is a fluid-sealed vibration damping device (10, 80, 100, 110), wherein an inner shaft member (14) and an intermediate cylinder member (24) are connected by a main body rubber elastomer (18), an outer cylinder member (16) is fixedly fitted onto the intermediate cylinder member (24), and a pocket-shaped portion (34) disposed on the main body rubber elastomer (18) and opening on the outer peripheral side of the intermediate cylinder member (24) is covered by the outer cylinder member (16), thereby forming a plurality of fluid chambers (38) separated in the circumferential direction, and a throttling passage (40, 81, 112) is provided in the vibration damping device (10, 80, 100, 110) to connect these plurality of fluid chambers (38), wherein, A magnetically functional fluid (39) is sealed in the fluid chamber (38). A magnetic field generating unit (56) is provided outside the fluid chamber (38), which applies a magnetic field to the magnetically functional fluid (39) flowing in the throttling channels (40, 81, 112). The outer cylinder component (16) is made of a non-magnetic material. The intermediate cylinder component (24) is made of a strongly magnetic material. In the intermediate cylinder component (24), a magnetic field opening (32) is provided at a position corresponding to the throttling passage (40, 81, 112) that applies a magnetic field to the magnetic functional fluid (39). The intermediate cylinder component (24) has: A pair of axially oriented lateral portions (29) are formed as a large-diameter cylindrical shape that is continuous in the circumferential direction; and The groove-shaped axial middle portion is partially provided in the circumferential direction and extends circumferentially between these pair of axial side portions (29). The magnetic field opening (32) is provided in the middle part of the axial direction. The intermediate cylinder component (24) is divided into two parts on both sides of the axial middle portion, and the pair of axial side portions (29) are independent components. The magnetic field-acting opening (32) is formed between the axially separated segments in the middle part of the axial direction.

2. The vibration damping device (10, 80, 100, 110) according to claim 1, wherein, The magnetic field generating unit (56) is disposed on the outer periphery of the outer cylinder component (16).

3. The vibration damping device (10, 80, 100) according to claim 1, wherein, In the throttling flow path (40, 81), a magnetic flux concentrating member (42) made of a strong magnetic material is disposed opposite each other in the width direction of the throttling flow path (40, 81), and the magnetic field action opening (32) in the intermediate cylinder member (24) is disposed at a position corresponding to the opposite part in the magnetic flux concentrating member (42).

4. The vibration damping device (80) according to claim 3, wherein, Between the intermediate cylinder member (24) and the outer cylinder member (16), throttling members (82, 102) for forming the throttling passage (81) are arranged to extend circumferentially at the opening of the pocket-shaped portion (34) provided in the main body rubber elastomer (18). The throttling components (82, 102) are made of strongly magnetic materials. The flux concentration member (42) disposed opposite each other in the width direction of the throttling path (81) is composed of the throttling member (82, 102).

5. The vibration damping device (10, 80, 100, 110) according to claim 1, wherein, The magnetic field generating unit (56) includes: A coil component that generates a magnetic field when energized; and The magnetic yoke component (60) guides the magnetic flux in the magnetic field generated by the coil component to the throttling path (40, 81, 112).

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