JP5689645B2 - Vibration isolator - Google Patents

Description

  The present invention relates to a fluid-filled vibration isolator that prevents transmission of vibration from a member that generates vibration, and more particularly, to a vibration isolator that is suitably used for an engine mount of an automobile.

  For example, in a vehicle such as a passenger car, an anti-vibration device serving as an engine mount is disposed between an engine serving as a vibration generating unit and a vehicle body serving as a vibration receiving unit. In this vibration isolator, when the inner cylinder and the outer cylinder move relative to each other in the axial direction due to vibrations generated from the engine, the elastic body connecting the two elastically deforms, so that the first main liquid chamber and the sub liquid chamber are not deformed. As the liquid moves, the vibration is attenuated. In addition, in the vibration isolator described in Patent Document 1, in addition to the above structure, two main liquid chambers (second main liquid chambers) are disposed in a direction (axial direction) orthogonal to the axial direction, These second main liquid chambers are communicated with the sub liquid chambers, and the vibration in the axial direction is attenuated by the liquid movement between the plurality of liquid chambers.

  By the way, in the vibration isolator having a structure capable of damping the vibration in the direction perpendicular to the axis as described above, a partition wall that partitions the plurality of second main liquid chambers is formed. This partition wall is required to have improved durability because stress is easily concentrated by the action of compressive and tensile forces in the axial direction.

JP 2002-310219 A

  In view of the above facts, an object of the present invention is to improve the durability of the partition wall in a vibration isolator that attenuates vibration not only in the axial direction but also in the direction perpendicular to the axial direction.

The vibration isolator of the invention according to claim 1 is connected to one of the vibration generating portion and the vibration receiving portion, and to the other of the vibration generating portion and the vibration receiving portion, and is viewed from the main vibration input direction. An outer peripheral member disposed so as to surround the outer periphery of the inner mounting member, and disposed between the inner mounting member and the outer peripheral member, elastically connecting the inner mounting member and the outer peripheral member, and the inner side An elastic having a liquid chamber between the mounting member and the outer peripheral member, and having an upper elastic body positioned on one side of the main vibration input direction with the liquid chamber interposed therebetween, and an elastic main body positioned on the other side A body, and the upper elastic body and the elastic main body in a compressed state in the main vibration input direction, and the liquid chamber is arranged in the outer peripheral direction of the inner mounting member. Partitioning partition walls that are partitioned into the outer peripheral member, The side mounting member is configured outside the main vibration input direction, and at least a part of the inner wall is formed by the elastic main body, and is filled with a liquid, filled with liquid, A first liquid chamber having a portion formed by a diaphragm and having an inner volume that can be expanded and contracted according to a change in liquid pressure, and the first main liquid chamber and the sub liquid chamber are connected to each other to allow the liquid to flow therethrough. A restriction passage, and a second restriction passage that enables liquid movement between the plurality of second main liquid chambers or between each of the second main liquid chambers and the sub liquid chamber , The compression rate in the main vibration input direction on the radially outer side of the partition wall is larger than the compression rate in the main vibration input direction on the radially inner side .

  In the vibration isolator according to claim 1, when vibration is input to either the inner mounting member or the outer peripheral member from the vibration generating unit side, the elastic body disposed between the inner mounting member and the outer peripheral member is elastically caused by the input vibration. The vibration is absorbed by the vibration absorbing action based on the internal friction or the like of the elastic body, and the vibration transmitted to the vibration receiving portion side is reduced. At this time, even if the input vibration is a vibration in the main vibration direction or a vibration in a direction substantially orthogonal to the main vibration, a part of the vibration is absorbed by the vibration absorbing action of the elastic body.

  Further, when vibration is input in the main vibration direction, the first main liquid chamber expands and contracts due to elastic deformation of the elastic body, and the liquid flows between the first main liquid chamber and the sub liquid chamber through the first restriction passage. . And a damping function is exhibited by liquid column resonance etc. in the 1st restriction passage.

  On the other hand, when vibration in a direction substantially orthogonal to the main vibration direction is input, the second main liquid chamber formed between the inner mounting member and the outer peripheral member is expanded and contracted by relative movement of the inner mounting member and the outer peripheral member. When the sub liquid chamber is in communication, the liquid flows between these liquid chambers. Further, when the plurality of second main liquid chambers partitioned by the partition wall are communicated with each other, the liquid flows between these liquid chambers. The vibration damping function is exhibited by the liquid column resonance caused by the liquid flow.

In the present embodiment, the partition wall is disposed so as to connect the upper elastic body and the elastic main body in a state compressed in the main vibration input direction. Thus, by arranging in a compressed state in the main vibration input direction, that is, by applying pre-compression, it is possible to suppress distortion of the partition wall during vibration input and improve the durability of the partition wall. .
Further, the radially inner side of the partition wall is a side close to the inner mounting member, and is a position corresponding to the central portion of the elastic main body. Therefore, when the compression rate on the radial center side of the partition wall is large, the influence on the spring constant of the elastic main body is increased. Therefore, as described above, the compression rate in the main vibration input direction on the radially outer side of the partition wall is made larger than the compression rate in the main vibration input direction on the radially inner side, thereby affecting the elastic main body. Pre-compression can be applied while suppressing.

  The vibration isolator according to claim 2 of the present invention is characterized in that the upper elastic body is connected to the outer peripheral member by an upper connecting member fixed to the outer periphery of the upper elastic body, and the elastic main body portion includes the elastic main body. It is connected with the said outer peripheral member by the lower connector fixed to the outer periphery of the part, It is characterized by the above-mentioned.

  As described above, by attaching the coupling tool (upper coupling tool, lower coupling tool) to the outer periphery of the upper elastic body and the elastic main body part and connecting the outer peripheral member via the coupling tool, assembly and positioning can be easily performed. Can do.

The vibration isolator according to claim 3 of the present invention is characterized in that a convex portion is formed on an outer surface corresponding to the partition wall of the upper elastic body.

  Thus, by forming a convex part on the outer surface corresponding to the partition wall of the upper elastic body, it is possible to increase the strength of the partition wall and suppress movement during vibration input.

In the vibration isolator according to claim 4 of the present invention, the inner mounting member is divided in the main vibration input direction, the upper elastic body is connected to one divided piece, and the upper divided body is connected to the other divided piece. The elastic main body part separated from the upper elastic body is connected.

  In this way, by dividing the inner mounting member and separately connecting the upper elastic body and the lower elastic body to the divided inner mounting members, the partition wall can be either the upper elastic body or the lower elastic body. On the other hand, it can be configured separately from both the upper elastic body and the lower elastic body, and distortion at the time of vibration input can be more effectively suppressed.

The vibration isolator according to claim 5 of the present invention is characterized in that the partition wall is formed with a slit from the radially outer side to the radially inner side.

  Thus, by forming the slit in the partition wall, the partition wall is divided into the upper elastic body side and the lower elastic body side with the slit interposed therebetween. Therefore, since the upper and lower parts divided at the time of vibration input can vibrate separately, distortion at the time of vibration input can be suppressed, and the durability of the partition wall can be improved.

  Since the present invention is configured as described above, the durability of the partition wall can be improved in the vibration isolator that attenuates vibration not only in the axial direction but also in the direction perpendicular to the axial direction.

It is sectional drawing of the axial direction which shows the structure of the vibration isolator which concerns on embodiment of this invention. It is sectional drawing of the axial direction in the position different from FIG. 1 of the vibration isolator which concerns on embodiment of this invention. It is sectional drawing of the axial direction which shows the structure of the main-body part of the vibration isolator which concerns on embodiment of this invention. It is sectional drawing of the axial direction in the position different from FIG. 3 of the main-body part of the vibration isolator which concerns on embodiment of this invention. It is 1-1 sectional drawing in FIG. 3 of the upper coupling tool of the vibration isolator which concerns on embodiment of this invention, an upper elastic body, and an upper metal fitting. It is 2-2 sectional drawing in FIG. 3 of the upper coupling tool of the vibration isolator which concerns on embodiment of this invention, an upper elastic body, an upper metal fitting, and a partition partition. It is sectional drawing of the lower coupling tool of the vibration isolator which concerns on embodiment of this invention, an elastic main-body part, and a lower metal fitting. It is the state before connection (A) and the connection state (B) of the partition partition wall and elastic main-body part of the vibration isolator which concern on embodiment of this invention. It is the state before connection (A) and the connection state (B) of the partition partition which concerns on the modification of the vibration isolator which concerns on embodiment of this invention, and an elastic main-body part. It is sectional drawing of one part of the vibration isolator which concerns on the modification of embodiment of this invention. It is sectional drawing different from FIG. 10 of one component of the vibration isolator which concerns on the modification of embodiment of this invention. It is sectional drawing of one part of the vibration isolator which concerns on the modification of embodiment of this invention. (A) of one part of the vibration isolator which concerns on the modification of embodiment of this invention is sectional drawing, (B) is a top view. It is.

Hereinafter, a vibration isolator according to an embodiment of the present invention will be described with reference to the drawings.
1 and 2 show a vibration isolator according to an embodiment of the present invention. The vibration isolator 10 is applied as an engine mount that supports an engine that is a vibration generating unit in an automobile to a vehicle body that is a vibration receiving unit. 1 indicates the axis of the apparatus, and the direction along this axis S is the axial direction of the apparatus. The vibration isolator of the present invention is installed so that the axial direction S becomes the main vibration input direction. Further, the following description will be made with the direction orthogonal to the axis S as the radial direction of the vibration isolator 10.

  As shown in FIGS. 1 and 2, the vibration isolator 10 includes a bracket 12 for connecting and fixing the vibration isolator 10 to the vehicle body side. The bracket 12 is provided with a cylindrical holder portion 12A and a pair of leg portions 12B extending in the radial direction from the lower end portion of the holder portion 12A. Attachment holes 14 for connecting the vehicle bodies are respectively provided at the distal ends of the pair of leg portions 12B.

  In the holder portion 12A of the bracket 12, a substantially cylindrical outer tube fitting 16 is disposed as an outer peripheral member having both axial ends opened. The outer cylinder fitting 16 is fitted to the inner peripheral surface of the holder portion 12A. An outer cylinder upper portion 16A having a slightly larger diameter than the outer cylinder intermediate portion 16B is configured on the upper side of the outer cylinder fitting 16, and a lower diameter than that of the outer cylinder intermediate portion 16B is formed on the lower side of the outer cylinder fitting 16. The outer cylinder lower portion 16C thus formed is configured. On the inner peripheral side of the outer cylinder fitting 16, a substantially cylindrical inner mounting fitting 18 is arranged coaxially with the outer cylinder fitting 16.

  The inner mounting bracket 18 is divided into a shaft-shaped lower bracket 18A positioned on the lower side of FIGS. 1 and 2 and a shaft-shaped upper bracket 18B positioned on the upper side of the lower bracket 18A. A convex portion 18C is formed on the upper side of the lower metal fitting 18A. A bolt shaft 18E that protrudes upward along the axis S is provided on the upper side of the upper metal part 18B, and a fitting hole 18D is formed on the lower side of the upper metal part 18B. The convex portion 18C of the lower metal fitting 18A is fitted into the fitting hole 18D of the upper metal fitting 18B, and the upper metal fitting 18B and the lower metal fitting 18A are connected. The upper metal fitting 18B and the lower metal fitting 18A have substantially the same outer diameter, and the shaft-shaped inner mounting metal fitting 18 is configured by connection.

  When the vibration isolator 10 is connected to the vehicle body side, a bolt (not shown) is inserted into each of the mounting holes 14 of the pair of leg portions 12B, and the tip portion is screwed to the vehicle body side, thereby 10 is fastened and fixed to the vehicle body side via the bracket 12. Further, the inner mounting bracket 18 is connected and fixed to the engine side of the vehicle via a bolt shaft 18E.

  On the inner peripheral surface of the outer cylinder fitting 16, an upper connector 20B and a lower connector 20A each formed in a ring shape from a metal material are arranged. The upper coupling tool 20B located on the upper side in FIGS. 1 and 2 has a larger diameter than the lower coupling tool 20A located on the lower side. The upper connector 20 </ b> B is connected to the outer tube fitting 16 by fitting the outer peripheral surface to the upper end portion of the inner periphery of the outer tube fitting 16. The lower connector 20A is connected to the outer cylinder fitting 16 by being fitted inside the outer cylinder fitting 16 via a partition member 26 described later.

  Between the lower connector 20A and the lower bracket 18A of the inner mounting bracket 18, an elastic main body 22A made of rubber and formed into a thick disk as a whole is disposed. The elastic main body 22A is connected to the outer peripheral surface of the lower metal fitting 18A and the inner peripheral surface of the lower connector 20A by vulcanization bonding. The lower surface of the elastic main body 22A is concave.

  Further, an upper elastic body 22B made of rubber and formed in a thick disk shape as a whole is disposed between the upper connector 20B and the upper metal fitting 18B of the inner attachment metal fitting 18. The upper elastic body 22B is vulcanized and connected to the outer peripheral surface of the upper metal fitting 18B and the inner peripheral surface of the upper connector 20B. Thereby, between the inner side attachment metal fitting 18 and the outer cylinder metal fitting 16 by the rubber elastic body 22 comprised by the elastic main-body part 22A and the upper elastic body 22B via the upper connection tool 20B and the lower connection tool 20A, respectively. It will be elastically connected.

  As shown in FIG. 1, the elastic main body 22A and the upper elastic body 22B are spaced apart in the axial direction S, and a liquid chamber 32 is formed between the elastic main body 22A and the upper elastic body 22B. ing. As shown in FIG. 3, the liquid chamber 32 is divided into a second main liquid chamber 32 </ b> A and a second main liquid chamber 32 </ b> B in the circumferential direction by the partition wall 23. The second main liquid chamber 32A and the second main liquid chamber 32B are filled with a liquid such as ethylene glycol or silicon oil.

  The partition wall 23 is made of rubber and is configured integrally with the upper elastic body 22B. As shown in FIG. 2, the partition wall 23 is arranged on the lower surface of the upper elastic body 22 </ b> B in a convex shape along the radial direction so as to partition the space between the elastic main body portion 22 </ b> A. As shown in FIG. 8B, the end of the partition wall 23 on the elastic body 22A side is in close contact with the elastic body 22A, and the radially outer end of the partition wall 23 is the inner wall of the outer cylinder fitting 16. Is in pressure contact.

  Both sides of the outer surface in the width direction of the partition wall 23 are sandwiched by the holding portions 24. The holding portion 24 is configured integrally with the elastic main body portion 22A on the upper surface of the elastic main body portion 22A. The holding portion 24 is configured as a pair of two convex shapes on both sides in the width direction of the partition wall 23 so as to sandwich the partition wall 23. The lower side of the partition wall 23 is held by the holding portion 24.

  In addition, the partition wall 23 is compressed in the axial direction S in a state where the upper connector 20B and the lower connector 20A are respectively held by the outer tube fitting 16 and the partition member 26. Here, the radially outer compression rate is preferably larger than the radially inner compression rate.

  As shown in FIGS. 1 and 2, a substantially disc-shaped partition member 26 is disposed below the elastic main body 22A (on the opposite side to the upper elastic body 22B). The partition member 26 is fitted and inserted into the outer cylinder fitting 16 so that the outer peripheral portion abuts on the step portion between the outer intermediate portion 16B and the outer lower portion 16C of the outer cylinder fitting 16. Further, the peripheral edge portion of the lower surface of the elastic main body portion 22 </ b> A is in pressure contact with the outer peripheral portion of the partition member 26.

  Thereby, the partition member 26 forms a space partitioned from the outside between the elastic main body portion 22A. This space is a first main liquid chamber 30 filled with a liquid such as ethylene glycol or silicon oil.

  A rubber diaphragm 48 formed in a thin film shape is vulcanized and bonded to the inner peripheral surface of the outer cylinder lower portion 16C of the outer cylinder fitting 16 so as to close the lower end portion of the outer cylinder fitting 16. As a result, a space partitioned from the outside by the diaphragm 48 and the partition member 26 is formed in the lower part of the outer tube fitting 16, and this space has a sub-liquid chamber 36 filled with a liquid such as ethylene glycol or silicon oil. Has been. A diaphragm 48, which is a part of the partition wall, can be elastically deformed so as to expand and contract the internal volume of the sub liquid chamber 36 in accordance with the pressure change of the liquid filled in the sub liquid chamber 36.

  An annular groove portion 54 is formed on the upper surface portion of the partition member 26 along the circumferential direction centering on the shaft center S over almost one turn. A communication hole 56 that penetrates to the lower surface of the partition member 26 is formed at one end of the groove 54. Further, as shown in FIG. 1, a circular concave portion 58 is formed in the inner peripheral side portion of the groove portion 54 in the partition member 26, and the bottom plate portion of the concave portion 58 penetrates to the lower surface of the partition member 26. A plurality of openings 60 are formed.

  A disk-shaped closing plate 62 is fixed to the partition member 26 so as to block the upper surface portion of the recess 58. A communication hole 64 is formed in a portion of the closing plate 62 that faces the other end of the groove 54. A plurality of openings 65 are formed in a portion of the closing plate 62 facing the recess 58.

  Here, the communication hole 56 and the groove 54 in the partition member 26 and the communication hole 64 of the closing plate 62 form a first orifice 38 as a restricting passage for communicating the first main liquid chamber 30 and the sub liquid chamber 36. Yes. The first main liquid chamber 30 and the sub liquid chamber 36 are communicated with each other via the first orifice 38, and the liquid can flow between the first main liquid chamber 30 and the sub liquid chamber 36. Yes.

  The concave portion 58 of the partition member 26 whose upper surface is closed by the closing plate 62 is configured as a storage chamber 70 for storing a rubber movable plate 68 as a membrane. The movable plate 68 is formed in a substantially disc shape, and has an outer diameter that is substantially the same as the inner diameter of the storage chamber 70 and is fitted in the storage chamber 70. An outer peripheral guide portion 68 </ b> A is formed on the outer peripheral portion of the movable plate 68 so as to project in a ring shape, and a central guide portion 68 </ b> B is formed on the central portion of the movable plate 68. The outer peripheral guide portion 68A and the central guide portion 68B are set slightly higher than the height along the axial direction of the storage chamber 70, and the two guide portions 68A and 68B are pre-compressed when the closing plate 62 is attached. It has become.

  On the radially outer side of the partition member 26, a ring portion 26 </ b> A having an outer diameter that corresponds to the inner diameter of the outer cylindrical metal fitting 16 and extending upward from the outer peripheral portion of the partition member 26 is formed. Yes. The ring portion 26 </ b> A is fitted and inserted into the inner peripheral surface of the outer cylindrical metal member 16, and the outer peripheral surface thereof is brought into pressure contact with the inner peripheral surface of the outer cylindrical metal member 16. The inner diameter of the ring portion 26A has an outer diameter corresponding to the lower connector 20A, and the inner peripheral surface of the ring portion 26A is in contact with the outer peripheral surface of the lower connector 20A. The lower end of the lower connector 20A is brought into contact with the upper surface of the partition member 26, and the upper end of the lower connector 20A is caulked to the upper end of the ring portion 26A extending upward from the partition member 26, The lower connector 20 </ b> A is fixed to the partition member 26, and the lower connector 20 </ b> A is connected to the outer cylinder fitting 16 through the partition member 26. The interval in the axial direction S between the upper connector 20B and the lower connector 20A is set so that the partition wall 23 is compressed at a predetermined compression rate.

  An outer peripheral groove 80 and an outer peripheral groove 81 extending in the vertical direction are formed at symmetrical positions on the outer peripheral surface of the ring portion 26A with the inner mounting bracket 18 in between. The ring portion 26A is formed with an upper communication port 82 penetrating from one end portion of the outer peripheral groove 80 to the upper end portion of the ring portion 26A, and the other end portion of the outer peripheral groove 80 is formed on the main body portion of the partition member 26 about a half circumference. It is connected to one end of the groove portion 84 formed so as to go around. At the other end of the groove 84, a lower communication port 86 penetrating toward the lower auxiliary liquid chamber 36 is formed.

  Further, an upper communication port 83 penetrating from one end portion of the outer peripheral groove 81 to the upper end portion of the ring portion 24A is formed in the ring portion 26A, and the other end portion of the outer peripheral groove 81 is approximately half a circumference around the main body portion of the partition member 26. It is connected to one end of the groove portion 85 formed so as to go around. At the other end of the groove 85, a lower communication port 87 that penetrates toward the lower auxiliary liquid chamber 36 is formed.

  Here, the outer peripheral side of the outer peripheral grooves 80, 81 of the ring portion 26 </ b> A is closed by the inner peripheral surface of the outer cylinder fitting 16. The outer peripheral groove 80 and the groove portion 84 whose outer peripheral side is closed constitute a second orifice 40 that allows the secondary liquid chamber 36 and the left second main liquid chamber 32B to communicate with each other. A second orifice 42 is configured to allow the chamber 36 and the right second main liquid chamber 32A to communicate with each other. In other words, the pair of second orifices 40 and 42 allows the liquid to flow between the pair of second main liquid chambers 32 </ b> A and 32 </ b> B and the sub liquid chamber 36. The second orifices 40 and 42 are set (tuned) so that the path length and the cross-sectional area thereof match a desired vibration frequency (for example, the frequency of pitching vibration “10 Hz to 15 Hz”).

  When assembling the vibration isolator 10 according to the present embodiment, first, the elastic body 22A is vulcanized between the lower fitting 18A and the lower connector 20A of the inner mounting fitting 18 as shown in FIG. . Similarly, the upper elastic body 22B and the partition wall 23 are vulcanized between the upper metal fitting 18B and the upper connector 20B, as shown in FIGS.

  Then, the inner fitting 18 is assembled by fitting the convex portion 18C of the lower fitting 18A into the fitting hole 18D of the upper fitting 18B. At this time, as shown in FIGS. 8A and 8B, the partition wall 23 is disposed in a recess formed by the two holding portions 24, and the partition wall 23 is held by the holding portion 24.

  Next, the lower connector 20 </ b> A is fitted into the partition member 26, and the upper connector 20 </ b> B and the partition member 26 are inserted into predetermined positions in the outer cylinder fitting 16. At this time, the partition member 26 is inserted from the upper side of the outer tubular fitting 16 so that the partition wall 23 is compressed and deformed as shown in FIG. 8B from the state shown in FIG. 20B is stored in the outer tube fitting 16. In this state, the entire outer tube fitting 16 is crimped to the inner peripheral side. Thereby, the upper connector 20B, the lower connector 20A, and the partition member 26 are fixed to the outer cylinder fitting 16. This assembling work is performed in a liquid prepared inside. Accordingly, the first main liquid chamber 30, the second main liquid chamber 32, the sub liquid chamber 36, the first orifice 38, and the second orifices 40 and 42 can be filled with liquid. Thereafter, the outer cylinder fitting 16 is inserted into the holder portion 12A of the bracket 12 and further fixed by caulking from the outside. The vibration isolator 10 can be manufactured as described above.

Next, the operation of the vibration isolator 10 according to the present embodiment configured as described above will be described.
In the present embodiment, when the engine connected to the inner mounting bracket 18 is operated, vibration from the engine is transmitted to the elastic main body 22A and the upper elastic body 22B constituting the rubber elastic body 22 via the inner mounting bracket 18. Is done. At this time, the elastic main body 22A mainly functions as a vibration absorber, the elastic main body 22A is elastically deformed, and the vibration is absorbed by the damping action based on the internal friction or the like, and the vibration transmitted to the vehicle body side is reduced.

  At this time, main vibrations input from the engine to the vibration isolator 10 include vibrations (main vibrations) generated by the reciprocating movement of pistons in the engine in the cylinder, and changes in the rotational speed of the crankshaft in the engine. Vibration (sub-vibration) generated by the operation. When the engine is a series type, the main vibration has an amplitude direction (main amplitude direction) that substantially matches the vertical direction of the vehicle, and the sub vibration has an amplitude direction (sub amplitude direction) that is the same as the main vibration amplitude direction. Substantially coincides with the vehicle longitudinal direction (when the engine is placed horizontally) or the left-right direction (when the engine is placed vertically).

  The rubber elastic body 22 is arranged along the sub-amplitude direction substantially orthogonal to the main amplitude direction, even if the input vibration is the main vibration along the main amplitude direction substantially coincident with the axial direction S of the vibration isolator 10. Even if it is a secondary vibration, a part of the vibration is absorbed by the damping action due to the internal friction or the like.

  When vibration along the main amplitude direction is input to the inner mounting bracket 18 from the engine side, the elastic main body portion 22A is elastically deformed mainly along the main amplitude direction and the internal volume of the first main liquid chamber 30 is increased. Scale up and down. For this reason, the liquid flows between the sub liquid chamber 36 whose internal volume can be expanded and contracted according to the change in the liquid pressure and the first main liquid chamber 30 via the first orifice 38.

  At this time, the path length and the cross-sectional area in the first orifice 38 are set so as to correspond to the vibration frequency (relatively low frequency band) in a predetermined band, and therefore the input main vibration is vibration in the corresponding band. In this case, a resonance phenomenon (liquid column resonance) occurs in the liquid flowing between the first main liquid chamber 30 and the sub liquid chamber 36 via the first orifice 38 in synchronization with the input vibration. Therefore, the vibration input along the main amplitude direction can be particularly effectively absorbed by the pressure change of the liquid accompanying the liquid column resonance and the viscous resistance.

  In addition, when the frequency of the main vibration to be input is higher than the frequency of the shake vibration and the amplitude thereof is small, for example, the input vibration is idle vibration (for example, 20 to 30 Hz) and the amplitude is about 0.1 mm to 0.2 mm. In this case, the first orifice 38 tuned to cope with the shake vibration is clogged, and it is difficult for the liquid to flow through the first orifice 38. However, the movable plate 68 vibrates along the axial direction in the storage chamber 70 in synchronization with the input vibration, so that the first through the gap between the inner wall surface of the storage chamber 70 and the movable plate 68 and the openings 60 and 65. The liquid flows between the one main liquid chamber 30 and the sub liquid chamber 36. As a result, an increase in the dynamic spring constant associated with an increase in the hydraulic pressure in the first main liquid chamber 30 can be suppressed, and the dynamic spring constant of the rubber elastic body 22 is kept low even when such high frequency vibration is input. High-frequency vibrations can also be effectively absorbed by elastic deformation of the rubber elastic body 22 or the like.

  On the other hand, when vibration along the sub-amplitude direction is input from the engine side to the inner mounting bracket 18, the contents of the second main liquid chambers 32 </ b> A and 32 </ b> B as the upper elastic body 22 </ b> B elastically deforms along the sub-amplitude direction. The product scales alternately. As a result, the second main liquid chambers 32A and 32B and the sub liquid chamber 36 are communicated with each other via the pair of second orifices 40 and 42, respectively, so that the second main liquid chambers 32A and 32B are synchronized with the input vibration. The liquid flows alternately between the liquid chambers 32A and 32B and the auxiliary liquid chamber. For this reason, when the input secondary vibration has a specific frequency, it flows between the second main liquid chambers 32A, 32B and the sub liquid chamber 36 via the pair of second orifices 40, 42. Since a resonance phenomenon occurs in the liquid, it is possible to particularly effectively absorb the vibration of a specific frequency input along the sub-amplitude direction due to pressure change, viscous resistance, and the like accompanying the resonance phenomenon of the liquid.

  On the other hand, in the present embodiment, the partition wall 23 that divides the second main liquid chamber 32 is formed integrally with the upper elastic body 22B, but is separate from the elastic main body 22A. . Further, the outer peripheral end face of the partition wall 23 is not vulcanized and bonded to the outer cylinder fitting 16 but is pressed against the inner wall of the outer cylinder fitting 16. Therefore, even when a vibration that causes a large deformation of the partition wall 23 is input to the vibration isolator 10 from the engine side, the partition wall 23 is relatively freely deformed and the concentration of stress is reduced at a specific location. As fatigue does not occur at 23, the durability of the vibration isolator 10 is improved.

  Furthermore, in this embodiment, since the partition wall 23 is arrange | positioned in the state compressed to the axial direction S, distortion of the partition wall 23 can be suppressed and durability can be improved more.

  In the present embodiment, both the outer side surfaces of the partition wall 23 are sandwiched by the holding portion 24, but other methods, for example, as shown in FIG. It is good also as a structure inserted in the groove | channel 25 comprised in the part 22A.

  In the present embodiment, the inner mounting bracket 18 is divided into two parts. However, as shown in FIGS. 10 and 11, the inner mounting bracket 18 is configured as a single member, and the upper elastic body 22B, the elastic main body 22A, In addition, the partition wall 23 may be integrally formed. By integrally forming, a simple configuration can be obtained, and the assembly is facilitated.

  Further, when the partition wall 23 is formed integrally with the upper elastic body 22B and the elastic main body 22A, the slit 23S is formed in the partition wall 23 from the outer peripheral surface toward the inner mounting bracket 18 as shown in FIG. May be formed. In the slit 23S, when the partition wall 23 or the like is assembled to the outer cylinder fitting 16, the gap between the slits is sealed by compression in the axial direction S of the partition wall 23. Thus, by forming the slit 23S, the upper part and the lower part of the partition wall 23 do not pull each other and are not easily influenced by the other party. Therefore, the partition wall 23 is relatively freely deformed, the stress concentration is relaxed, and the durability of the partition wall 23 can be improved.

  In the present embodiment, the second main liquid chambers 32A and 32B and the sub liquid chamber 36 are communicated with each other via the second orifices 40 and 42. However, the second main liquid chamber 32A and the second main liquid chamber You may comprise the orifice which connects between 32B. In this case, the second orifices 40 and 42 may be provided, or the second orifices 40 and 42 may not be provided.

  Further, as shown in FIG. 13, the upper elastic body 22 </ b> B of this embodiment may be formed with a protrusion 22 </ b> D on the outer surface (upper surface) corresponding to the partition wall 23. Thus, by forming the protrusion 22D, the strength of the partition wall 23 can be increased, and the movement at the time of vibration input can be suppressed.

DESCRIPTION OF SYMBOLS 10 Vibration isolator 16 Outer cylinder metal fitting 18A Lower metal fitting 18B Upper metal fitting 18 Inner attachment metal fitting 20A Lower coupling tool 20B Upper coupling tool 22 Rubber elastic body 22B Upper elastic body 22A Elastic main-body part 22D Projection 23S Slit 23 Partition partition 30 First main Liquid chamber 32 Liquid chamber 32A Second main liquid chamber 32B Second main liquid chamber 38 First orifice 40 Second orifice 42 Second orifice 48 Diaphragm S Axial direction

Claims (5)

An inner mounting member connected to one of the vibration generator and the vibration receiver;
An outer peripheral member connected to the other of the vibration generating unit and the vibration receiving unit, and disposed so as to surround the outer periphery of the inner mounting member when viewed from the main vibration input direction;
Arranged between the inner mounting member and the outer peripheral member, elastically connecting the inner mounting member and the outer peripheral member and forming a liquid chamber between the inner mounting member and the outer peripheral member; An upper elastic body located on one side of the main vibration input direction across the liquid chamber, and an elastic body having an elastic main body located on the other side;
It arrange | positions so that the said upper elastic body and an elastic main-body part may be connected in the state compressed in the said main vibration input direction, and the said liquid chamber is divided into several 2nd main liquid chambers in the outer peripheral direction of the said inner side attachment member. A partition wall;
A first main liquid chamber that is configured outside the main vibration input direction of the inner mounting member on the inner side of the outer peripheral member, at least a part of an inner wall is formed by the elastic main body, and is filled with a liquid;
A sub liquid chamber in which a part of the partition wall is formed by a diaphragm and the internal volume can be expanded and contracted in accordance with a change in liquid pressure, while being filled with liquid;
A first restricting passage that allows the liquid to flow through the first main liquid chamber and the sub liquid chamber by communicating with each other;
A second restriction passage that enables movement of liquid between the plurality of second main liquid chambers or between each of the second main liquid chambers and the sub liquid chamber;
Equipped with a,
A vibration isolator having a compressibility in a main vibration input direction on a radially outer side of the partition wall is larger than a compressibility in a main vibration input direction on a radially inner side .   The upper elastic body is connected to the outer peripheral member by an upper connecting member fixed to the outer periphery of the upper elastic body, and the elastic main body portion is connected to the outer peripheral member by a lower connecting member fixed to the outer periphery of the elastic main body portion. The anti-vibration device according to claim 1, wherein the anti-vibration device is connected to the anti-vibration device.   The anti-vibration device according to claim 1, wherein a convex portion is formed on an outer surface of the upper elastic body corresponding to the partition wall.   The inner mounting member is divided in the main vibration input direction, the upper elastic body is connected to one divided piece, and the elastic main body portion separated from the upper elastic body is connected to the other divided piece. It is connected, The vibration isolator of any one of Claims 1-3 characterized by the above-mentioned.   The vibration isolator according to any one of claims 1 to 4, wherein a slit is formed in the partition wall from a radially outer side toward a radially inner side.

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