Anti-vibration system

Abstract

The invention provides an anti-vibration system which can be mounted on a vehicle by arbitrarily selecting either a negative pressure type or a non-negative pressure type using a fluid-sealed anti-vibration device having a common structure. The present invention is an anti-vibration system (10) using fluid-filled anti-vibration devices (12, 13), in which a portion of a wall portion of a fluid chamber (20) in each of the fluid-filled anti-vibration devices is configured from a diaphragm (64), and an active air chamber (68) is formed on the side opposite the fluid chamber with respect to the diaphragm. The anti-vibration system is provided with a switching valve (90) which is provided with a first port (92) and a second port (94), and which selectively switches and communicates the ports with respect to the working air chamber, the first port (92) being an open atmosphere structure, and the second port (94) being a fluid-filled anti-vibration device. A blocking structure which is selectively equipped with a cap (102) and is closed by the cap; and a suction structure which is connected with a negative pressure source (106) and applies negative pressure to the working air chamber.

Description

Technical Field

[0001] The present invention relates to an anti-vibration system using a plurality of different fluid-sealed anti-vibration devices having fluid sealed therein, and more particularly to an anti-vibration system in which each fluid-sealed anti-vibration device includes an operating air chamber and a switching valve communicating with the operating air chamber. Background Art

[0002] Conventionally, as a vibration-proof device such as a vibration-proof support body or a vibration-proof connecting body interposed between components constituting a vibration transmission system, a fluid-sealed vibration-proof device is known that obtains a vibration-proof effect based on a flow action such as a resonance action of an incompressible fluid sealed inside. Such a fluid-sealed vibration-proof device is proposed, for example, in Japanese Patent Application Laid-Open No. 2007-162876 (Patent Document 1).

[0003] In particular, the fluid-sealed vibration-proof device described in Patent Document 1 includes an operating air chamber and a switching valve connected to the operating air chamber, and is configured as a negative pressure type fluid-sealed vibration-proof device that selectively connects the operating air chamber to the atmosphere and a predetermined negative pressure source by switching the switching valve. In such a fluid-sealed vibration-proof device, the vibration-proof characteristics in the vibration-proof device are changed by switching the switching valve, thereby exerting a vibration-proof effect on vibrations of multiple different frequencies.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Publication No. 2007-162876 Summary of the invention

[0007] Problems to be solved by the invention

[0008] However, in a vehicle using a fluid-sealed vibration-proof device such as Patent Document 1, a switching valve is switched at idle to connect the working air chamber to a negative pressure source, thereby suppressing idle vibration in the fluid-sealed vibration-proof device by a vibration-proof mechanism such as a throttle passage tuned to a frequency of idle vibration, etc. In addition, as a negative pressure source connected to such a working air chamber, for example, engine intake negative pressure is sometimes used.

[0009] However, in recent years, with the increase in direct injection engine-equipped vehicles and idling stop vehicles, it is sometimes impossible to use the engine suction negative pressure as the negative pressure source. In such cases, it is also considered to use a non-negative pressure type vibration isolation device, but in other cases, there are still many cases where a negative pressure type vibration isolation device is used. Therefore, from the perspective of cost, environment, etc., a vibration isolation system that can share a fluid-sealed vibration isolation device in both negative pressure and non-negative pressure types is required.

[0010] Furthermore, when constructing a vibration isolation system using a plurality of fluid-sealed vibration isolation devices, the vibration isolation characteristics of the active air chamber in each fluid-sealed vibration isolation device need to be tuned to a desired frequency, and a vibration isolation system capable of more easily tuning spring characteristics is desired.

[0011] The present invention has been made against the background of the above situation, and aims to solve the problem of providing a new vibration isolation system that can be mounted on a vehicle by arbitrarily selecting either a negative pressure type or a non-negative pressure type using a fluid-filled vibration isolation device having a common structure.

[0012] Another problem to be solved by the present invention is to provide a new vibration isolation system capable of easily tuning the spring characteristics of each working air chamber in a plurality of fluid-sealed vibration isolation devices.

[0013] Means used to solve problems

[0014] The following describes the preferred modes for understanding the present invention, but the modes described below are illustrative modes, and can be used in combination with each other as appropriate. The multiple components described in each mode can also be identified and used as independently as possible, and can also be used in combination with any components 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.

[0015] The first method is a vibration isolation system, which uses a fluid-sealed vibration isolation device in which a first mounting component and a second mounting component are connected by a main rubber elastic body and a fluid chamber is formed inside, wherein in any of the fluid-sealed vibration isolation devices, a portion of the wall of the fluid chamber is formed by a diaphragm, and an effective air chamber is formed on the side opposite to the fluid chamber relative to the diaphragm, and the vibration isolation system is provided with a switching valve having a first port and a second port and selectively switching and connecting these ports relative to the effective air chamber, the first port is an atmospheric open structure in any of the fluid-sealed vibration isolation devices, and the second port in each of the fluid-sealed vibration isolation devices can be selected as a blocking structure equipped with a cap and closed by the cap or a suction structure connected to a negative pressure source and applying negative pressure to the effective air chamber.

[0016] According to the present method, it is possible to arbitrarily select either a negative pressure type or a non-negative pressure type using a fluid-sealed vibration isolating device of a common structure. That is, in a case where the second port of the switching valve is connected to a negative pressure source (for example, the engine intake negative pressure) to form a suction structure that applies negative pressure to the working air chamber, the fluid-sealed vibration isolating device becomes a negative pressure type fluid-sealed vibration isolating device that is the same as in the past. On the other hand, in a case where a cap is assembled to the second port of the switching valve and a blocking structure is used to seal the working air chamber, the fluid-sealed vibration isolating device becomes a non-negative pressure type fluid-sealed vibration isolating device that does not have a negative pressure source (for example, the engine intake negative pressure). In this way, by setting the second port of the switching valve to either a suction structure or a blocking structure, it is possible to arbitrarily select either a negative pressure type or a non-negative pressure type. In the vibration isolation system of the present method, not only the fluid-sealed vibration isolating device but also the switching valve is a common structure. In other words, in the vibration isolation system of this method, a fluid-sealed vibration isolation device with a common structure up to the switching valve can be applied to vehicles with a negative pressure source (for example, engine intake negative pressure) and vehicles without a negative pressure source (for example, engine intake negative pressure).

[0017] A second aspect is the vibration isolation system according to the first aspect, wherein the vibration isolation system includes a switching control device that controls switching of the switching valve, and the switching control device switches the switching valve in the same control in any of the fluid-sealed vibration isolation devices.

[0018] According to this method, in a negative pressure fluid-sealed vibration isolation device (i.e., the second port is a suction structure) and a non-negative pressure fluid-sealed vibration isolation device (i.e., the second port is a blocking structure), without changing the switching control device of the switching valve, the target characteristics can be obtained by a common control method in either when the cap is assembled or when the negative pressure source is connected.

[0019] The third method is a vibration isolation system, which uses a fluid-sealed vibration isolation device in which a first mounting member and a second mounting member are connected by a main rubber elastic body and a fluid chamber is formed inside, wherein in any of the fluid-sealed vibration isolation devices, a portion of the wall of the fluid chamber is formed by a diaphragm, and an effective air chamber is formed on the side opposite to the fluid chamber relative to the diaphragm, and the vibration isolation system is provided with a switching valve having a first port and a second port and selectively switching and connecting these ports relative to the effective air chamber, the first port is open to the atmosphere in any of the fluid-sealed vibration isolation devices, and the second port is equipped with a sealing tube in any of the fluid-sealed vibration isolation devices, and the end opening of the sealing tube on the opposite side of the second port is sealed, and in these fluid-sealed vibration isolation devices, the length of the sealing tube is adjusted separately according to the required spring characteristics of the effective air chamber.

[0020] According to this method, in a fluid-sealed vibration isolation device in which a sealing tube is installed at the second port of the switching valve, when the switching valve is switched and the working air chamber is connected to the second port, the working air chamber and the internal space of the second port and the sealing tube become one space, so the internal volume of the one space can be adjusted by adjusting the length of the sealing tube, and the compressibility of the air in the sealing tube can be used to simply tune the characteristics in the state where the working air chamber is connected to the second port.

[0021] The fourth method is based on the vibration isolation system of any one of the first to third methods, wherein the first port is equipped with an open tube in any of the fluid-sealed vibration isolation devices, and in these fluid-sealed vibration isolation devices, the length of the open tube is adjusted according to the required spring characteristics of the working air chamber.

[0022] According to this method, in a fluid-sealed vibration isolation device in which an open tube is installed at the first port of a switching valve, when the switching valve is switched and the working air chamber is connected to the first port, the internal space of the working air chamber, the first port and the open tube become one space, so the internal volume of the one space can be adjusted by adjusting the length of the open tube, and the characteristics in the state where the working air chamber is connected to the first port can be simply tuned using the resonance phenomenon of the air in the open tube.

[0023] Effects of the Invention

[0024] According to the present invention, it is possible to provide a new vibration isolation system that can be mounted on a vehicle by arbitrarily selecting either a negative pressure type or a non-negative pressure type using a fluid-filled vibration isolation device having a common structure.

[0025] According to another aspect of the present invention, it is possible to provide a new vibration isolation system capable of easily tuning the spring characteristics of each working air chamber in a plurality of fluid-sealed vibration isolation devices. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is an explanatory diagram for modeling a vibration isolation system in one embodiment of the present invention.

[0027] Figure 2 It is composed Figure 1 The longitudinal cross-sectional view of the fluid-filled vibration isolation device of the vibration isolation system shown is a diagram showing the fluid-filled vibration isolation device having a blocking structure in which the second port is blocked by a cap.

[0028] Figure 3 It is composed Figure 1 The longitudinal cross-sectional view of the fluid-sealed vibration isolation device of the vibration isolation system shown is a diagram showing the fluid-sealed vibration isolation device having a suction structure in which a negative pressure source is connected to the second port.

[0029] Figure 4 It means in the composition Figure 1 FIG. 1 is a graph showing the relationship between the length of the tube and the spring characteristics in the working air chamber in the fluid-sealed vibration isolation device of the vibration isolation system shown.

[0030] Description of Reference Numerals

[0031] 10: Anti-vibration system;

[0032] 12, 12', 13: engine bracket (fluid-enclosed anti-vibration device);

[0033] 14: first mounting member;

[0034] 16: second mounting member;

[0035] 18: Main rubber elastic body;

[0036] 20: Fluid chamber;

[0037] 22: bolt hole;

[0038] 24: Step part;

[0039] 26: Large diameter cylinder;

[0040] 28: small diameter cylinder;

[0041] 29: Chimeric protrusion;

[0042] 30: Large diameter concave part;

[0043] 32: Sealing rubber layer;

[0044] 34: partition member;

[0045] 36: cover member;

[0046] 38: partition member body;

[0047] 40: Central fovea;

[0048] 42: step surface;

[0049] 44: Peripheral groove;

[0050] 45: connecting window;

[0051] 46: annular protrusion;

[0052] 48: Constraint configuration area;

[0053] 50: through hole;

[0054] 52: movable plate;

[0055] 54: fixed component;

[0056] 56: Lower concave part;

[0057] 68: central protuberance;

[0058] 59: Fitting groove;

[0059] 60: upper side fitting groove;

[0060] 62: lower side fitting groove;

[0061] 64: diaphragm;

[0062] 66: interlocking ring;

[0063] 68: working air chamber;

[0064] 70: air passage;

[0065] 72: port;

[0066] 74: partition;

[0067] 76: Fixing metal parts;

[0068] 78: chimeric protrusion;

[0069] 80: main liquid chamber;

[0070] 82: Balance chamber;

[0071] 84: auxiliary liquid chamber;

[0072] 86: throttling passage;

[0073] 88: air pipeline;

[0074] 90: switching valve;

[0075] 92: first port;

[0076] 94: Second port;

[0077] 96: Switching control device;

[0078] 98: open tube;

[0079] 100: blocking tube;

[0080] 102: hat;

[0081] 104: connecting pipe;

[0082] 106: Negative pressure source. DETAILED DESCRIPTION

[0083] Hereinafter, in order to clarify the present invention more specifically, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0084] First, in Figure 1 FIG. 1 shows a vibration isolation system 10 according to an embodiment of the present invention. The vibration isolation system 10 includes Figure 2 The non-negative pressure fluid-sealed vibration-proof device shown is an engine mount 12 (12') and Figure 3 The negative pressure type fluid-sealed vibration isolation device shown is the engine bracket 13. Most of these engine brackets 12 (12') and 13 have a common structure. In the following description, the common structure of the two engine brackets 12 (12') and 13 will be described first. Any engine bracket 12 (12') and 13 has a basic structure, having a structure in which a first mounting member 14 and a second mounting member 16 are connected by a main rubber elastic body 18, and a fluid chamber 20 is formed inside the engine bracket 12. It should be noted that the engine bracket 12 and the engine bracket 12' are both non-negative pressure types, but the length dimensions of the open tube 98 and the sealing tube 100 described later are different from each other. In addition, in the following description, unless otherwise specified, the up and down direction refers to the direction of the bracket axis. Figure 2 The up and down directions in .

[0085] More specifically, the first mounting member 14 is generally columnar and extends in the vertical direction. In particular, in the present embodiment, the lower portion of the first mounting member 14 is generally cup-shaped and opens downward. On the other hand, a bolt hole 22 for fastening with a bolt (not shown) is provided in the upper portion of the first mounting member 14 so as to open upward. The first mounting member 14 is integrally provided with a generally cup-shaped portion at the lower portion and a generally cylindrical portion having the bolt hole 22 at the upper portion.

[0086] The second mounting member 16 has a generally stepped cylindrical shape as a whole, and is formed in the middle portion in the axial direction, with a large diameter cylindrical portion 26 formed above and a small diameter cylindrical portion 28 formed below across a stepped portion 24. A generally annular fitting protrusion 29 protruding toward the inner circumference is formed at the lower end of the small diameter cylindrical portion 28. Furthermore, the first mounting member 14 is separated and arranged on the opening side above the second mounting member 16, and the central axes of the two members 14 and 16 are located on a substantially colinear line, and a main rubber elastic body 18 is arranged between the first mounting member 14 and the second mounting member 16.

[0087] The main rubber elastic body 18 has a generally truncated cone shape as a whole, and is fixed in a state where the lower portion of the first mounting member 14 is generally embedded in its small diameter side end surface. In addition, the outer peripheral surface of the large diameter side end of the main rubber elastic body 18 is fixed to the inner peripheral surface of the large diameter cylinder 26 and the step portion 24 of the second mounting member 16. In the present embodiment, the main rubber elastic body 18 is formed as an integral vulcanized molded part including the first mounting member 14 and the second mounting member 16. Thus, the first mounting member 14 and the second mounting member 16 are elastically connected by the main rubber elastic body 18, and the upper opening of the large diameter cylinder 26 of the second mounting member 16 is closed by the main rubber elastic body 18 in a fluid-tight manner.

[0088] A large diameter recess 30 opening downward is formed on the large diameter side end surface of the main rubber elastic body 18. A sealing rubber layer 32 integrally formed with the main rubber elastic body 18 is fixed to the inner peripheral surface of the small diameter cylindrical portion 28 of the second mounting member 16 with a substantially constant thickness.

[0089] In addition, in the integral vulcanized molded part of the main rubber elastic body 18 including the first mounting member 14 and the second mounting member 16, a partition member 34 is assembled from the lower opening side of the second mounting member 16. The partition member 34 of this embodiment is generally cup-shaped and opens downward, and is formed of a hard synthetic resin. In particular, in this embodiment, the partition member 34 is composed of an upper cover member 36 and a lower partition member body 38.

[0090] The outer diameter of the partition member body 38 is smaller than the inner diameter of the small diameter cylindrical portion 28 of the second mounting member 16, and a central recess 40 opening downward is formed in the central portion of the lower surface of the partition member body 38. A circular stepped surface 42 is formed on the inner peripheral surface of the peripheral wall portion of the central recess 40, which is located in the middle portion of the axial direction (depth direction) and extends in a direction perpendicular to the axis. As a result, the inner diameter of the central recess 40 above the stepped surface 42 is smaller than the inner diameter below the stepped surface 42.

[0091] In addition, a peripheral groove 44 is formed on the peripheral wall portion of the partition member body 38. The peripheral groove 44 is opened on the outer peripheral surface and extends to a predetermined length in the circumferential direction. One end of the peripheral groove 44 is opened upward through a communication window 45 provided at the upper end of the partition member body 38, and the other end of the peripheral groove 44 is opened downward through a communication window (not shown) provided at the lower end of the partition member body 38.

[0092] In addition, an annular protrusion 46 in a circular ring shape protruding upward is provided on the upper end surface of the peripheral wall portion of the partition member body 38. Thus, an upper concave portion opening upward is formed on the inner circumference side of the annular protrusion 46 on the upper end surface of the partition member body 38. The inner diameter dimension of the annular protrusion 46 is substantially equal to the inner diameter dimension of the central concave portion 40 above the step surface 42. The upper opening of the upper concave portion is covered by the cover member 36 overlapping the partition member body 38 from above.

[0093] The cover member 36 is generally in the shape of a disk that opens downward, and the upper opening of the upper recess and the lower opening of the cover member 36 are respectively butted against each other, overlapping the upper end surface of the annular protrusion 46 in the partition member body 38. The fixing method of the cover member 36 and the partition member body 38 is not limited, and they can be fixed by welding or bonding. The space between the cover member 36 and the upper recess in the partition member body 38 forms the restraint arrangement area 48.

[0094] In the partition member body 38 and the cover member 36, a plurality of through holes 50 penetrating in the up-down direction are formed in the portion constituting the upper and lower walls of the constraint arrangement area 48. Through these through holes 50, the internal space of the constraint arrangement area 48 is connected to the external space on both sides of the up-down direction. Moreover, a movable plate 52 made of an elastic body such as rubber is accommodated and arranged in the constraint arrangement area 48. The movable plate 52 is generally in the shape of a thin-walled, roughly circular plate and is located in the central part of the constraint arrangement area 48. The up-down dimension of the movable plate 52 is smaller than the distance between the opposing surfaces of the upper and lower walls of the constraint arrangement area 48, thereby enabling the movable plate 52 to be displaced in the up-down direction inside the constraint arrangement area 48.

[0095] On the partition member 34 composed of these cover members 36 and the partition member main body 38, a fixing member 54 is assembled in an overlapping manner from the axial bottom. The fixing member 54 is generally in the shape of a circular plate and is formed of a hard synthetic resin. A lower side recess 56 opening downward is provided in the central portion of the lower surface of the fixing member 54. In addition, a central protrusion 58 protruding upward is integrally formed in the central portion of the fixing member 54. A roughly circular recess opening upward is formed on the upper end surface of the central protrusion 58. A fitting groove 59 extending in an annular shape throughout the entire circumference is provided on the outer peripheral surface of the protruding base end (lower end) of the central protrusion 58.

[0096] In the fixing member 54, the upper end surface of the outer peripheral side of the central protrusion 58 is a substantially annular flat surface extending in a direction perpendicular to the axis, and a communication hole (not shown) penetrating in the up-down direction is formed in the outer peripheral portion of the fixing member 54. The communication hole is formed at a position corresponding to the communication window at the other end of the circumferential groove 44, and the upper side and the lower side (lower side recess 56) of the fixing member 54 are connected to each other. In addition, on the outer peripheral surface of the fixing member 54, an upper fitting groove 60 and a lower fitting groove 62 extending over the entire circumference are formed at the upper end portion and the lower end portion, respectively.

[0097] The fixing member 54 is fixed by, for example, fitting the concave and convex portions provided respectively into the partition member 34. These concave and convex portions are formed, for example, with a certain circumferential length. Thus, the upper end surface of the fixing member 54 overlaps the lower end surface of the partition member 34 with substantially no gap.

[0098] Moreover, a diaphragm 64 is assembled to the central protrusion 58 of the fixing member 54. The diaphragm 64 is a thin-walled, generally circular plate-shaped body formed of an elastic body such as rubber. A plurality of concave-convex, grooves, protrusions, etc. are formed on both sides of the diaphragm 64, and the thickness dimensions are different in the circumferential direction. A generally cylindrical interlocking ring 66 is fixed to the outer peripheral end of the diaphragm 64. In the present embodiment, the diaphragm 64 is formed as an integrally formed part having the interlocking ring 66. The lower end of the interlocking ring 66 is bent toward the inner peripheral side, and the lower end of the interlocking ring 66 is inserted into the interlocking groove 59 of the central protrusion 58, whereby the diaphragm 64 is assembled to the fixing member 54 in a manner covering the upper opening of the central protrusion 58.

[0099] Furthermore, an action air chamber 68 is formed between the bottom of the central protrusion 58 and the diaphragm 64. In addition, an air passage 70 is formed through the fixing member 54. One end of the air passage 70 opens at the upper surface of the central protrusion 58 and is connected to the action air chamber 68, and the other end of the air passage 70 opens at the outer peripheral surface of the fixing member 54. The other end of the air passage 70 is a substantially cylindrical port portion 72 that protrudes from the outer peripheral surface of the fixing member 54 toward the outer peripheral side.

[0100] In this way, the fixing member 54 in which the diaphragm 64 is assembled to the central protrusion 58 is assembled to the partition member 34 from below, so that the outer peripheral end of the diaphragm 64 and the upper end of the fitting ring 66 overlap with the stepped surface 42 of the central recess 40 provided below the partition member 34. Thus, the central recess 40 opened downward in the partition member 34 is covered by the diaphragm 64.

[0101] The assembly of the fixing member 54 and the partition member 34 is inserted from the lower opening of the second mounting member 16, and the fitting protrusion 29 at the lower end of the second mounting member 16 is fitted into the upper fitting groove 60 of the fixing member 54, so that the fixing member 54 and the partition member 34 are assembled to the second mounting member 16. Thus, the second mounting member 16 is externally fitted and fixed to the upper end of the fixing member 54.

[0102] In addition, a partition 74 is assembled at the lower end of the fixing member 54 exposed from the lower end of the second mounting member 16. The partition 74 is a thin-walled circular plate as a whole, formed of an elastic body such as rubber, and can be easily flexed and deformed. A substantially cylindrical fixing metal piece 76 is fixed to the outer peripheral end of the partition 74, and a substantially annular fitting protrusion 78 protruding toward the inner peripheral side is formed at the upper end of the fixing metal piece 76. The partition 74 is assembled below the fixing member 54 by inserting the fixing metal piece 76 into the fixing member 54 and inserting the fitting protrusion 78 into the lower fitting groove 62 of the fixing member 54. As a result, the opening of the lower recess 56 in the fixing member 54 is covered by the partition 74 in a fluid-tight manner. In short, the lower opening of the second mounting member 16 is covered by the partition 74 via the fixing member 54, and the partition member 34 and the fixing member 54 are arranged between the axially opposing surfaces of the main rubber elastic body 18 and the partition 74.

[0103] Thus, a fluid chamber 20 closed from the external space is formed between the main rubber elastic body 18 and the facing surface of the partition plate 74, and a non-compressible fluid is sealed in the fluid chamber 20. As the sealed fluid, for example, water, alkylene glycol, polyalkylene glycol, silicone oil, etc. are used, but in particular, in order to effectively obtain the vibration-proof effect based on the flow action such as the resonance action of the fluid, it is preferable to use a low-viscosity fluid of 0.1 Pa·s or less.

[0104] In addition, as described above, the partition member 34 and the fixing member 54 are arranged in the fluid chamber 20 so as to expand in the direction perpendicular to the axis, and the fluid chamber 20 is divided into two parts in the upper and lower directions in the axial direction by the partition member 34 and the fixing member 54. In the fluid chamber 20, a part of the wall portion is formed by the main rubber elastic body 18 above the partition member 34 and the fixing member 54, and when vibration is input between the first mounting member 14 and the second mounting member 16, a main liquid chamber 80 is formed, which generates pressure changes based on the elastic deformation of the main rubber elastic body 18. On the other hand, in the fluid chamber 20, a balance chamber 82 is formed below the partition member 34 and the fixing member 54, and a part of the wall portion of the balance chamber 82 is formed by the partition plate 74, and the volume change is easily allowed by the deformation of the partition plate 74.

[0105] In addition, as described above, the lower opening of the central recess 40 in the partition member body 38 is covered by the diaphragm 64, and the auxiliary liquid chamber 84 is formed between the partition member body 38 and the diaphragm 64. In the auxiliary liquid chamber 84, a non-compressible fluid is sealed in the same manner as the main liquid chamber 80 and the balance chamber 82, and a part of the fluid chamber 20 is constituted by the auxiliary liquid chamber 84. Thus, a part of the wall of the fluid chamber 20 is constituted by the diaphragm 64. In addition, the auxiliary liquid chamber 84 is formed above the diaphragm 64, and the working air chamber 68 is formed below. In other words, the working air chamber 68 is formed on the side opposite to the fluid chamber 20 (auxiliary liquid chamber 84) with respect to the diaphragm 64.

[0106] In addition, the main liquid chamber 80 and the auxiliary liquid chamber 84 are separated in the vertical direction by the restraint arrangement area 48 of the partition member 34, and the movable plate 52 is arranged inside the restraint arrangement area 48 in a state that it can be displaced in the vertical direction by a predetermined amount. The pressure of the main liquid chamber 80 and the auxiliary liquid chamber 84 acts on the upper surface and the lower surface of the movable plate 52 respectively through the plurality of through holes 50. Moreover, when vibration is input, the pressure change of the main liquid chamber 80 is released to the auxiliary liquid chamber 84 based on the change of the relative pressure difference between the main liquid chamber 80 and the auxiliary liquid chamber 84.

[0107] Furthermore, the partition member 34 and the fixing member 54 are assembled to the second mounting member 16, and the outer peripheral opening of the peripheral groove 44 of the partition member body 38 is covered by the small diameter cylinder 28 of the second mounting member 16 in a fluid-tight manner via the sealing rubber layer 32, thereby forming a throttle passage 86. One end of the throttle passage 86 is connected to the main liquid chamber 80 through the communication window 45 of the partition member body 38. In addition, the other end of the throttle passage 86 is connected to the balance chamber 82 through the communication window and the communication hole (not shown) of the partition member body 38 and the fixing member 54. Thus, the main liquid chamber 80 and the balance chamber 82 are connected to each other through the throttle passage 86, and the fluid flowing through the throttle passage 86 is allowed between the two chambers 80 and 82. The throttle passage 86 is tuned to the following state: the resonance frequency of the fluid flowing in the throttle passage 86 exerts an effective vibration-proof effect (vibration insulation effect based on low dynamic spring characteristics) for vibrations in a frequency band (for example, about tens of Hz) equivalent to idling vibrations, etc. based on the resonance action of the fluid.

[0108] In the engine mount 12 (or the engine mount 12', 13) of this structure, the first mounting member 14 is fixed to the member on the power unit side by the bolt (not shown) fastened to the bolt hole 22, and the large diameter cylinder portion 26 of the second mounting member 16 is fixed to the bracket (not shown) and fixed to the member on the vehicle body side. Thus, the engine mount 12 (or the engine mount 12', 13) is assembled between the power unit and the vehicle body, and the power unit is supported in a vibration-proof manner relative to the vehicle body.

[0109] Here, an air line 88 is connected to the port portion 72 of the fixing member 54, and the port portion 72, the air passage 70, and the internal space of the working air chamber 68 are connected to the switching valve 90 through the air line 88. The switching valve 90 is a three-way valve provided with a first port 92 and a second port 94, and the switching is controlled by a switching control device 96 provided in the vehicle, and the first port 92 and the second port 94 are selectively selected to communicate with the port portion 72 and the air line 88. That is, the switching valve 90 is also an electromagnetically switched solenoid valve, and the first port 92 and the second port 94 are selectively switched by the switching valve 90 to communicate with the working air chamber 68.

[0110] The switching control device 96 inputs necessary information from various sensors equipped in the vehicle, such as the vehicle speed, engine speed, speed reducer selection position, throttle opening, etc., among various information indicating the state of the vehicle, and based on the information, switches the switching valve 90 through the software of the microcomputer, etc. according to a pre-set program. In addition, by appropriately switching the switching valve 90 according to the vibration input under various conditions such as the driving state of the vehicle, the pressure of the action air chamber 68 for obtaining the target vibration-proof effect is controlled. In the present embodiment, both the non-negative pressure type engine mount 12 (12') and the negative pressure type engine mount 13 are equipped with the switching control device 96, and the switching valve 90 is switched by the control of the switching control device 96.

[0111] Furthermore, an open pipe 98 is connected to the first port 92 of the switching valve 90 , and the open pipe 98 is open to the atmosphere. That is, the first port 92 is an atmosphere-opening structure in any of the engine mounts 12 ( 12 ′) and 13 .

[0112] The above is the common structure of the engine brackets 12 (12') and 13. Figure 2 The non-negative pressure engine bracket 12 (12') shown is Figure 3 The difference of the negative pressure type engine mount 13 shown will be described.

[0113] exist Figure 2In the engine bracket 12 (12') shown, a plugging tube 100 is connected to the second port 94, and a cap 102 is mounted on the end opening of the plugging tube 100 on the opposite side of the side connected to the second port 94. The plugging tube 100 and the cap 102 are made of synthetic resin, for example, and may have a certain degree of deformation rigidity. The fixing structure of the plugging tube 100 and the cap 102 is not limited, and may be bonding, welding, etc., but for example, an external thread may be provided on the outer peripheral surface of the end opening of the plugging tube 100 on the side where the cap 102 is mounted, and an internal thread may be provided on the inner peripheral surface of the cap 102, and the cap 102 is mounted on the end opening of the plugging tube 100 by screwing these external threads and internal threads to seal the plugging tube 100. In addition, the plugging tube 100 has a certain length dimension.

[0114] In such a structure, when the switching valve 90 is switched by the switching control device 96 to communicate the air pipe 88 (port portion 72) with the second port 94, the internal spaces of the working air chamber 68, the air passage 70, the port portion 72, and the air pipe 88 communicate with the internal space of the blocking tube 100, but by fixing the cap 102 at the end of the blocking tube 100, these internal spaces become closed spaces, and the change in volume is prevented or suppressed, and the diaphragm 64 exerts a spring rigidity harder than that in the state where the working air chamber 68 is open to the atmosphere through the open tube 98. In this case, the second port 94 is set to a blocking structure in which the cap 102 is attached to the blocking tube 100 connected to the second port 94 and is closed by the cap 102.

[0115] On the other hand, Figure 3 In the engine mount 13 shown, a connection pipe 104 is connected to the second port 94, and a negative pressure source 106 is mounted on the end of the connection pipe 104 opposite to the side connected to the second port 94. The negative pressure source 106 may utilize, for example, negative pressure sucked by the engine.

[0116] In such a structure, when the switching valve 90 is switched by the switching control device 96 to communicate the air pipe 88 (port portion 72) with the second port 94, the diaphragm 64 is deformed by negative pressure suction toward the working air chamber 68 side by applying suction force from the negative pressure source 106, or the diaphragm 64 is more strongly sucked and overlaps with the bottom surface of the working air chamber 68, thereby being restrained by deformation and exerting a hard spring rigidity. In this case, the second port 94 is connected to the negative pressure source 106 via the connecting pipe 104, and a suction structure is formed to apply negative pressure to the working air chamber 68.

[0117] When vibrations such as idle vibrations are input to the engine mounts 12 (12') and 13 as described above, a relatively large amplitude pressure change is caused in the main liquid chamber 80. In this case, in each engine mount 12 (12') and 13, the switching valve 90 is switched by the switching control device 96 so that the air pipe 88 is connected to the second port 94 (cap 102 or negative pressure source 106), thereby preventing or suppressing the deformation of the auxiliary liquid chamber 84. As a result, the pressure change of the main liquid chamber 80 is suppressed from being released to the auxiliary liquid chamber 84, and a good vibration-proof effect is exerted by the flow of the fluid through the throttle passage 86 tuned to the idle vibration.

[0118] In particular, Figure 2 In the non-negative pressure type engine mount 12 (12') shown, as described above, the volume of the closed space including the working air chamber 68 is determined not only by the working air chamber 68, but also by the air passage 70, the port portion 72, the air pipe 88, and the internal space of the blocking tube 100. That is, the volume of the closed space can be adjusted by setting the blocking tube 100 to an appropriate length. In addition, the air spring of the closed space (internal space) acts on the diaphragm 64 as an auxiliary or restraining spring, so the hardness of the diaphragm 64 is determined by the volume of the closed space.

[0119] The inventor prepared a plurality of plugging tubes 100 of different actual lengths, manufactured a plurality of engine brackets 12, 12' of different lengths of the plugging tubes 100, and obtained the frequency characteristics of the vibration-proof characteristics (absolute spring constant) of the engine brackets 12, 12' based on the spring characteristics of the active air chamber 68 (hardness of the diaphragm 64) in each engine bracket 12, 12' and the resonance effect of the fluid flowing in the throttle hole passage 86 that changes accordingly. In this experiment, a plugging tube (plugging tube + 0 mm) was prepared as a reference, and plugging tubes that were lengthened by 50 mm (plugging tube + 50 mm), 100 mm (plugging tube + 100 mm), and 150 mm (plugging tube + 150 mm), respectively. The results are shown in the graph as follows. Figure 4 It should be noted that Figure 4 In the graph, the vertical axis represents the absolute spring constant of the engine mount 12, 12' (particularly the main rubber elastic body 18) in a linear scale (general scale), and the vertical axis represents a higher spring constant as it goes up, and a lower spring constant as it goes down. Figure 4As can be seen from the circled portion in the figure, the length of the plugging tube 100 is different, and thus the volume of the closed space including the working air chamber 68 also changes, and the spring characteristic of the diaphragm 64 (the hardness of the diaphragm 64) changes, and thus the resonance valley frequency in the spring characteristic of the engine mount 12, 12' based on the flow action of the fluid flowing in the throttle passage 86 changes. Specifically, by further lengthening the plugging tube 100, the resonance valley frequency becomes a lower frequency, and by appropriately setting the length dimension of the plugging tube 100, the resonance valley frequency in the spring characteristic of the engine mount 12, engine mount 12' based on the flow action of the fluid flowing in the throttle passage 86 can be adjusted to a desired value. It should be noted that in the negative pressure type engine mount 13, a substantially constant suction restraining force acts on the diaphragm 64, and the length dimension of the connecting tube 104 does not affect the spring characteristic of the working air chamber 68, so the length dimension of the connecting tube 104 is set to an appropriate length based on considerations such as replacement. Therefore, as the connection pipe 104 , for example, a pipe similar to the blocking pipe 100 used in the non-negative pressure type engine mount 12 ( 12 ′) may be used.

[0120] On the other hand, when a high-frequency, small-amplitude vibration such as a driving roar is input to the engine mount 12 (12'), 13, the switching valve 90 is switched to connect the air pipe 88 to the first port 92. The first port 92 is connected to the atmosphere via the open pipe 98, so the diaphragm 64 exerts a relatively soft spring characteristic. As a result, along with the displacement of the movable plate 52 in the constraint arrangement area 48, the pressure change of the main liquid chamber 80 is effectively transmitted to the auxiliary liquid chamber 84, and the pressure change of the main liquid chamber 80 is reduced or eliminated by the hydraulic absorption effect based on the elastic deformation of the diaphragm 64, and a good vibration-proof effect is exerted. In addition, when a high-frequency, small-amplitude vibration is input, the throttle passage 86 tuned to a frequency band lower than it becomes substantially closed due to the effect of anti-resonance, and the fluid flow resistance becomes significantly larger.

[0121] It should be noted that if Figure 1 As shown, by appropriately setting the length dimension of the open tube 98, the volume of the internal space from the working air chamber 68 to the external space can be changed in a state where the air pipe 88 is communicated with the first port 92, thereby adjusting the spring characteristics of the diaphragm 64, that is, the working air chamber 68. As a result, in the vibration-proof mechanism for the flow of fluid through each through hole 50 between the main liquid chamber 80 and the auxiliary liquid chamber 84, the resonance frequency can be tuned by making the length dimension of the open tube 98 different.

[0122] The vibration isolation system 10 of the present embodiment having the above-described structure can be used in a vehicle that does not have a negative pressure source 106 (for example, engine suction negative pressure). Figure 2The engine mount 12 (12') shown can be used in a vehicle having a negative pressure source 106 (e.g., engine suction negative pressure). Figure 3 The engine mount 13 shown in the figure has a common structure for most of these engine mounts 12, 12', and 13. Specifically, in the engine mounts 12 and 12', a blocking tube 100 and a cap 102 are connected to the second port 94, and in the engine mount 13, a connecting tube 104 and a negative pressure source 106 are connected to the second port 94. In short, by selecting whether to set the second port 94 as a blocking structure or a suction structure, and connecting any one of the cap 102 and the negative pressure source 106 to the tube (blocking tube 100 or connecting tube 104) connected to the second port 94, a non-negative pressure type engine mount 12 (12') and a negative pressure type engine mount 13 can be arbitrarily selected. As a result, by constructing an anti-vibration system 10 that combines an engine bracket 12 (12') and an engine bracket 13, it is possible to easily and efficiently cope with both a vehicle that does not have a negative pressure source 106 (for example, engine suction negative pressure) and a vehicle that has a negative pressure source 106 (for example, engine suction negative pressure) at a low cost, wherein the engine bracket 12 (12') has a blocking structure that connects the cap 102 to the second port 94 via a blocking tube 100, and the engine bracket 13 has a suction structure that connects the negative pressure source 106 to the second port 94 via a connecting tube 104.

[0123] In particular, in either the non-negative pressure type engine mount 12 (12') or the negative pressure type engine mount 13, the same switching control device 96 for switching the switching valve 90 can be used, and there is no need to change the switching control device 96 when selecting the non-negative pressure type engine mount 12 (12') or the negative pressure type engine mount 13. Thus, in each mode, the control system can also be made common without major changes, and only by changing whether the connection cap 102 is connected to the negative pressure source 106, it is possible to cope with both the vehicle without the negative pressure source 106 and the vehicle with the negative pressure source 106.

[0124] In addition, in the non-negative pressure type engine mounts 12 and 12', by making the length of the blocking tube 100 connected to the second port 94 different, the spring characteristics in the working air chamber 68 when the air pipe 88 (port portion 72) is connected to the second port 94 are adjusted. As a result, for example, in a vibration isolation mechanism having a throttle passage 86, etc., the resonance frequency can be easily tuned, and by preparing a plurality of blocking tubes 100 of different lengths, a plurality of non-negative pressure type engine mounts 12 and 12' having different spring characteristics of the working air chamber 68 can be used in various vehicles that do not have a negative pressure source 106 (for example, engine suction negative pressure). As a result, the vibration isolation system 10 can be configured by a plurality of non-negative pressure type engine mounts 12 and 12' having different lengths of the blocking tubes 100 and a negative pressure type engine mount 13.

[0125] Similarly, by making the length of the open tube 98 connected to the first port 92 different, the spring characteristic in the working air chamber 68 when the air pipe 88 (port portion 72) is connected to the first port 92 is adjusted. As a result, in any of the non-negative pressure type and negative pressure type engine mounts 12 (12'), 13, the resonance frequency in the vibration isolation mechanism caused by the flow between the main liquid chamber 80 and the auxiliary liquid chamber 84 can be easily tuned, and the vibration isolation system 10 including a plurality of engine mounts 12, 12', 13 whose resonance frequencies are set to desired values ​​can be constructed.

[0126] Above, one embodiment of the present invention is described in detail, but according to the specific description in the embodiment, the present invention is not limited in any way and can be implemented in a manner with various changes, corrections, improvements, etc. based on the knowledge of those skilled in the art. In addition, as long as it does not deviate from the main purpose of the present invention, such embodiments are included in the scope of the present invention.

[0127] For example, in the above embodiment, the main liquid chamber 80 and the balance chamber 82 are connected through the throttle passage 86, and the vibration-proof mechanism of the throttle passage 86 is tuned to the vibration of the medium frequency and medium amplitude equivalent to the idling vibration, and the vibration-proof mechanism of the main liquid chamber 80 and the auxiliary liquid chamber 84 is tuned to the vibration of the high frequency and small amplitude equivalent to the running roar, but it is not limited to this mode. That is, for example, the fluid-sealed vibration-proof device can also be applied to other than the engine bracket, and can also suppress vibrations other than the idling vibration and the running roar illustrated in the above embodiment. Moreover, in the fluid-sealed vibration-proof device, the vibration (frequency, amplitude, etc.) as the vibration-proof object is not limited, for example, as long as the vibration-proof effect is exerted on at least one of various vibrations such as low-frequency large-amplitude vibration, medium-frequency medium-amplitude vibration, and high-frequency small-amplitude vibration. The number of throttle passages is also not limited, and two or more throttle passages can be set according to the vibration as the vibration-proof object. For example, in an engine mount having a basic structure as in the above-mentioned embodiment, a second throttle passage connecting the main liquid chamber and the auxiliary liquid chamber may be provided, and the second throttle passage may be tuned to a frequency band different from that of the first throttle passage. The flow characteristics of the fluid passing through the second throttle passage and the vibration-proof characteristics exerted by the second throttle passage may also be appropriately adjusted by changing the spring hardness of the diaphragm constituting a part of the wall portion of the auxiliary liquid chamber by switching the switching valve. The second throttle passage is preferably tuned to a higher frequency band than the first throttle passage. It should be noted that in the fluid-sealed vibration-proof device of the present invention, the throttle passage connecting the main liquid chamber and the balance chamber includes a balance chamber but is not required. For example, in a fluid-sealed vibration-proof device without a balance chamber, the low-frequency large-amplitude vibration (for example, engine shaking) and the medium-frequency medium-amplitude vibration (for example, idling vibration) can be suppressed by the flow of the fluid in the throttle passage connecting the main liquid chamber and the auxiliary liquid chamber, and the vibration-proof characteristics can be changed and set based on the switching of the switching valve. In addition, the specific control method of the switching operation of the switching valve can be appropriately set according to the type of vibration to be prevented, input conditions, etc., and is not limited to this.

[0128] In addition, in the above embodiment, the cap 102 is mounted on the end opening of the plugging tube 100 on the opposite side of the side connected to the second port 94, thereby the plugging tube 100 is closed, but according to one embodiment of the present invention, the cap may not be provided, for example, the plugging tube may be closed by welding or bonding the inner circumferential surface of the plugging tube, or the end opening of the plugging tube may be closed by filling other components. It should be noted that the fixing method of the plugging tube 100 and the cap 102 is not limited to the screwing of the external thread and the internal thread illustrated in the above embodiment, for example, it may be press-fitting, or it may be concave-convex fitting, etc.

[0129] In addition, in the above-mentioned embodiment, the engine mounts 12 and 12' are exemplified as the fluid-sealed anti-vibration device, and the engine suction negative pressure is exemplified as the negative pressure source 106, but it is not limited to this method. The fluid-sealed anti-vibration device can be a fluid-sealed anti-vibration device for vehicles other than engine mounts such as body mounts and differential mounts, or it can be a fluid-sealed anti-vibration device other than vehicles. Similarly, the negative pressure source used in the fluid-sealed anti-vibration device can be a negative pressure source provided in the vehicle other than the engine suction negative pressure, or it can be a negative pressure source provided outside the vehicle.

[0130] The fluid-sealed vibration isolation device of the present invention only needs to include, for example, an operating air chamber and a switching valve connected to the operating air chamber. The sealing tube and / or cap connected to the second port of the switching valve in the fluid-sealed vibration isolation device may or may not constitute the fluid-sealed vibration isolation device.

[0131] In the above-mentioned embodiment, the vibration isolation system 10 is constructed to include a plurality of non-negative pressure engine mounts 12, 12' and a negative pressure engine mount 13 having different length dimensions of the sealing tube 100, but is not limited to this embodiment. In one embodiment of the vibration isolation system of the present invention, the length dimension of the sealing tube in the non-negative pressure engine mount may be constant, and the vibration isolation system may be constructed by combining the non-negative pressure engine mount and the negative pressure engine mount. In addition, in another embodiment of the vibration isolation system of the present invention, the negative pressure engine mount is not necessary, and the vibration isolation system may be constructed by a plurality of non-negative pressure engine mounts having different length dimensions of the sealing tube.

Claims

1. A vibration isolation system (10) using a fluid-sealed vibration isolation device (12, 12', 13) in which a first mounting member (14) and a second mounting member (16) are connected by a main rubber elastic body (18) and a fluid chamber (20) is formed inside, wherein: In any of the fluid-sealed vibration isolation devices (12, 12', 13), a portion of the wall of the fluid chamber (20) is formed by a diaphragm (64), an action air chamber (68) is formed on the side of the diaphragm (64) opposite to the fluid chamber (20), and the vibration isolation system (10) is provided with a switching valve (90) having a first port (92) and a second port (94) and selectively switching and connecting the first port (92) and the second port (94) relative to the action air chamber (68). The first port (92) is an atmosphere-opening structure in any of the fluid-sealed vibration-proof devices (12, 12', 13). The second port (94) in each of the fluid-sealed anti-vibration devices (12, 12', 13) can be selected to be a blocking structure that is equipped with a cap (102) and is sealed by the cap (102) or a suction structure that is connected to a negative pressure source (106) and applies negative pressure to the working air chamber (68).

2. The vibration isolation system (10) according to claim 1, wherein: The vibration prevention system (10) includes a switching control device (96) for controlling the switching of the switching valve (90). The switching control device (96) switches the switching valve (90) in the same control in any of the fluid-sealed vibration isolation devices (12, 12', 13).

3. A vibration isolation system (10) using a fluid-sealed vibration isolation device (12, 12', 13) in which a first mounting member (14) and a second mounting member (16) are connected by a main rubber elastic body (18) and a fluid chamber (20) is formed inside, wherein: In any of the fluid-sealed vibration isolation devices (12, 12', 13), a portion of the wall of the fluid chamber (20) is formed by a diaphragm (64), an action air chamber (68) is formed on the side of the diaphragm (64) opposite to the fluid chamber (20), and the vibration isolation system (10) is provided with a switching valve (90) having a first port (92) and a second port (94) and selectively switching and connecting the first port (92) and the second port (94) relative to the action air chamber (68). The first port (92) is open to the atmosphere in any of the fluid-sealed vibration isolation devices (12, 12', 13). The second port (94) is equipped with a blocking tube (100) in any of the fluid-sealed anti-vibration devices (12, 12', 13), and the end opening of the blocking tube (100) on the opposite side to the second port (94) is blocked. In these fluid-sealed vibration isolation devices (12, 12', 13), the length of the blocking tube (100) is adjusted according to the required spring characteristics of the active air chamber (68).

4. The vibration isolation system (10) according to any one of claims 1 to 3, wherein: The first port (92) is equipped with an open pipe (98) in any of the fluid-sealed anti-vibration devices (12, 12', 13). In these fluid-sealed vibration isolation devices (12, 12', 13), the length of the open tube (98) is adjusted according to the required spring characteristics of the working air chamber (68).

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