JP5907782B2 - Fluid filled vibration isolator - Google Patents

Description

  The present invention relates to a vibration isolator used for, for example, an automobile engine mount, and more particularly to a fluid filled type vibration isolator utilizing a vibration isolating effect based on a flow action of an incompressible fluid sealed inside. is there.

  Conventionally, the flow action of incompressible fluid sealed inside is used as a type of vibration isolator that is interposed between the members constituting the vibration transmission system and supports the vibration isolation connection or vibration isolation of these members. A fluid-filled vibration isolator is known, and its application to an engine mount or the like is being studied. In this fluid filled type vibration isolator, the first mounting member and the second mounting member are elastically connected by the main rubber elastic body, and incompressible on both sides of the partition member supported by the second mounting member. Each of the pressure receiving chamber and the equilibrium chamber in which the fluid is sealed is formed, and a first orifice passage is formed to communicate the pressure receiving chamber and the equilibrium chamber with each other. For example, it is shown in Unexamined-Japanese-Patent No. 2008-157411 (patent document 1).

  By the way, in the fluid filled type vibration isolator, an excellent anti-vibration effect is exhibited with respect to the vibration input in the frequency range in which the first orifice passage is tuned, while higher than the tuning frequency of the first orifice passage. At the time of vibration input in the frequency range, the first orifice passage is substantially clogged, so that there is a problem of a decrease in vibration isolation performance due to high dynamic springs due to anti-resonance.

  Therefore, in Patent Document 1, a second orifice passage tuned to a frequency higher than that of the first orifice passage is formed, and a valve body that switches the second orifice passage between a communication state and a cutoff state is provided. It is disclosed. According to this, the second orifice passage is brought into a communication state at the time of vibration input having a frequency higher than that of the first orifice passage, so that effective prevention can be performed based on the fluid action of the fluid flowing through the second orifice passage. A vibration effect can be obtained.

  However, when vibration is input at a frequency higher than the tuning frequency of the second orifice passage, even if the valve body holds the second orifice passage in a communicating state, the second orifice passage is substantially anti-resonant. Blocked. Therefore, it is difficult to prevent a decrease in the vibration proof performance in the high frequency region, and depending on the required characteristics, the frequency region in which an effective vibration proof effect can be obtained is still insufficient. In addition, in the structure in which the opening of the second orifice passage formed in the hard partition member is blocked by the valve body coming into contact with the partition member, the hitting sound at the time of contact may be a problem.

  In addition, by providing a hydraulic pressure absorbing mechanism in addition to the second orifice passage, an effective vibration-proofing effect due to a low dynamic spring is provided for vibration input at a frequency higher than the tuning frequency of the second orifice passage. It can also be realized. However, it is necessary to add other parts such as a movable plate and a movable film in order to configure the hydraulic pressure absorbing mechanism, and it is difficult to avoid an increase in the number of parts and a complicated structure.

JP 2008-157411 A

  The present invention has been made in the background of the above-mentioned circumstances, and the solution to the problem is that it is possible to effectively obtain an anti-vibration effect with respect to input vibrations in a wider frequency range with a simple structure and at the time of switching characteristics. It is an object of the present invention to provide a fluid-filled vibration isolator having a novel structure capable of preventing the occurrence of abnormal noise.

That is, according to the first aspect of the present invention, the first mounting member and the second mounting member having the cylindrical portion are elastically connected by the main rubber elastic body and supported by the second mounting member. A pressure receiving chamber in which a part of the wall is formed of the main rubber elastic body is formed on one side of the partition member, and a part of the wall is formed on the other side of the partition member. Are formed of a flexible membrane, incompressible fluid is sealed in the pressure receiving chamber and the equilibrium chamber, and a first orifice that communicates the pressure receiving chamber and the equilibrium chamber with each other In the fluid-filled vibration isolator having a passage formed therein, the partition member is formed with a communication channel that connects the pressure receiving chamber and the equilibrium chamber to each other, and an intermediate portion in the fluid flow direction in the communication channel the communicating flow so as to project one of the opposing walls in An elastic protrusion disposed within the elastic valve and a slow collision portion disposed so as to project to the other the counter wall in the intermediate portion of the fluid flow direction in the communicating passage in the communicating passage While the member is configured, a valve body that protrudes in the flow path length direction of the communication flow path and can be displaced in a swinging manner is provided at the protruding tip portion of the elastic protrusion, and the elastic protrusion And a second orifice passage that communicates the pressure-receiving chamber and the equilibrium chamber with each other by using a region between opposing surfaces of the first and the buffer protrusions, and the second orifice passage is formed in the first orifice passage. It is tuned to a frequency higher than that of the orifice passage, and is characterized in that the second orifice passage is blocked by the elastic protrusion being elastically deformed and coming into contact with the buffer protrusion. .

  According to the fluid-filled vibration isolator having the structure according to the first aspect as described above, the elastic protruding piece is elastically deformed by a relative pressure difference between the pressure receiving chamber and the equilibrium chamber when low frequency large amplitude vibration is input. Then, the second orifice passage is blocked by abutting against the buffer protrusion. As a result, the amount of fluid flowing between the pressure receiving chamber and the equilibrium chamber through the first orifice passage can be efficiently ensured, and a vibration isolation effect based on the fluid flow action can be effectively obtained. .

  Further, when vibration is input in the frequency range (medium frequency range) in which the second orifice passage is tuned, the contact of the elastic projection piece with the buffer projection is released, and the second orifice passage is held in communication. The Accordingly, since the fluid flows between the pressure receiving chamber and the equilibrium chamber through the second orifice passage, a vibration isolation effect based on the fluid flow action is exhibited.

  Furthermore, when vibration is input in a frequency range higher than the tuning frequency of the second orifice passage, the elastic projecting piece is elastically deformed based on the relative pressure fluctuation of the pressure receiving chamber with respect to the equilibrium chamber, thereby changing the volume of the pressure receiving chamber. Is allowed, and the vibration insulation effect due to the low dynamic spring is effectively exhibited. Thus, according to the fluid-filled vibration isolator of this aspect, any effective vibration isolating effect can be obtained against vibrations in a wider frequency range.

  In addition, the anti-vibration effect based on the hydraulic pressure transmission action against the input vibration in the high frequency range is exhibited by the hydraulic pressure transmission mechanism configured using an elastic protrusion that switches between communication and blocking of the second orifice passage. It has come to be. Therefore, a fluid-filled vibration isolator capable of exhibiting an effective vibration isolating effect against vibrations in a wide frequency range can be realized with a simple structure having a small number of parts.

  In addition, since the second orifice passage is blocked by the elastic projection piece formed of an elastic body coming into contact with the buffer projection formed of the elastic body, the second orifice passage Generation of a contact hitting sound, which is likely to be a problem when shutting off, is prevented.

According to a second aspect of the present invention, in the fluid-filled vibration isolator described in the first aspect, an arrangement region of the elastic valve member in the communication channel extends in a circumferential direction of the partition member as a whole. The elastic protrusion protrudes on either the inner peripheral surface or the outer peripheral surface of the arrangement region, and extends on either the inner peripheral surface or the outer peripheral surface of the arrangement region. The buffer protrusion is provided in a protruding manner.

  According to the second aspect, since the elastic valve member is annular, the free length of the elastic valve member located on the communication channel is reduced, and the elastic deformation amount of the elastic protruding piece is limited. Therefore, when the low-frequency large-amplitude vibration is input, the amount of fluid flowing through the first orifice passage can be more efficiently ensured by suppressing the hydraulic pressure transmission action due to the elastic deformation of the elastic protrusion. Thus, it is possible to advantageously obtain a vibration isolation effect based on the fluid flow action.

  According to a third aspect of the present invention, in the fluid-filled vibration isolator described in the first or second aspect, the elastic protrusion and the buffer protrusion are separate from each other. .

  According to the third aspect, even if the area between the opposing surfaces of the elastic protrusion and the buffer protrusion is a narrow slit or the like, it is possible to suppress variations in shape due to narrowing due to burrs or dimensional errors. It can be formed with high accuracy. Therefore, it is possible to set the tuning frequency of the second orifice passage, switching between communication and blocking of the second orifice passage, etc. with high accuracy, and to obtain the desired vibration isolation characteristics stably.

  According to a fourth aspect of the present invention, in the fluid-filled vibration isolator described in any one of the first to third aspects, a channel length of the communication channel is provided at a protruding tip portion of the elastic protruding piece. The valve body which protrudes in both directions is provided, and the said buffering protrusion is provided in the position facing the base end part of this valve body.

  According to the fourth aspect, the valve body is displaced in a swinging manner by the elastic deformation of the elastic protruding piece, so that when the low-frequency large-amplitude vibration is input, the valve is applied to both pressurization and decompression of the pressure receiving chamber. The body comes into contact with the buffer protrusion and the second orifice passage is blocked. Therefore, the escape of hydraulic pressure through the second orifice passage is prevented, and the vibration isolation effect based on the fluid action of the fluid flowing through the first orifice passage is efficiently exhibited.

  According to a fifth aspect of the present invention, in the fluid-filled vibration isolator described in any one of the first to fourth aspects, a flow path length of the communication flow path is provided at a protruding tip portion of the elastic protruding piece. A valve body projecting in the direction, and a taper surface is provided at the projecting tip portion of the buffer projection, and the elastic projection piece is elastically deformed so that the valve body is The second orifice passage is blocked by contacting the tapered surface.

  According to the fifth aspect, the valve body of the elastic projection piece is displaced in a swinging manner and abuts against the taper surface of the buffer protrusion, so that the valve body and the buffer protrusion touch the surface, and the second orifice The passage is stably blocked without causing a hydraulic pressure leak or the like.

  In addition, when the second orifice passage is formed by a portion outside the tapered surface in the region between the opposing surfaces of the elastic protrusion and the buffer protrusion, the tuning frequency of the second orifice passage can be further increased by forming the tapered surface. It becomes easy to set to a high frequency, and the degree of freedom of tuning of the second orifice passage can be increased.

  According to the present invention, the second orifice passage is formed by using the region between the opposing surfaces of the elastic protrusion and the buffer protrusion, and the elastic protrusion is elastically deformed to contact the buffer protrusion. Thus, the second orifice passage is blocked. Accordingly, the vibration isolation effect by the first orifice passage is effectively exhibited when the low frequency vibration is input, and the vibration isolation effect by the second orifice passage is exhibited when the medium frequency vibration is input. Furthermore, when high-frequency vibration is input, the anti-vibration effect based on the hydraulic pressure transmission action due to the elastic deformation of the elastic protrusion is exerted, so that an effective anti-vibration effect can be obtained for vibration input in a wide frequency range. it can.

  In addition, both the valve mechanism for switching between communication and blocking of the second orifice passage and the hydraulic pressure transmission mechanism for exhibiting the anti-vibration effect against high-frequency vibration are formed using elastic protrusions, and the number of parts is increased. And the accompanying complexity of the structure can be prevented. In addition, since the elastic projecting piece formed of an elastic body and the buffer projecting part are in contact with each other, the contact sound that becomes a problem when the second orifice passage is blocked is reduced.

1 is a longitudinal sectional view showing an engine mount as one embodiment of the present invention. The top view of the partition member which comprises the engine mount shown by FIG. The bottom view of the partition member shown by FIG. The expanded sectional view of the elastic valve member which comprises the partition member shown by FIG. The longitudinal cross-sectional view which expands and shows the principal part of the engine mount as another one Embodiment of this invention.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 shows an engine mount 10 for an automobile as an embodiment of a fluid filled type vibration damping device structured according to the present invention. The engine mount 10 has a structure in which a first mounting member 12 and a cylindrical second mounting member 14 are elastically connected by a main rubber elastic body 16. In the following description, the vertical direction refers to the vertical direction in FIG.

  More specifically, the first mounting member 12 is a high-rigidity member formed of iron, aluminum alloy, or the like, has a small-diameter, generally cylindrical shape, and a flange that protrudes to the outer peripheral side in the axially intermediate portion. The stopper portion 18 is integrally provided. Further, the first mounting member 12 is formed with a screw hole 20 extending in the vertical direction and opening on the upper surface, and a thread is engraved on the inner peripheral surface thereof.

  The second mounting member 14 has a thin, large-diameter, generally cylindrical shape, and an upper end portion is integrally provided with a tapered portion 22 that increases in diameter upward. An annular stepped portion 24 is integrally provided at the lower end portion of the second mounting member 14, and a caulking piece 26 protruding downward from the outer peripheral end of the stepped portion 24 is integrally formed. In the present embodiment, since the entire second mounting member 14 has a substantially cylindrical shape, the entire second mounting member 14 forms a cylindrical portion.

  The first mounting member 12 is disposed above the second mounting member 14, and the first mounting member 12 and the second mounting member 14 are elastically connected to each other by the main rubber elastic body 16. . The main rubber elastic body 16 has a thick and large-diameter substantially truncated cone shape, and the first attachment member 12 is vulcanized and bonded to the end portion on the small-diameter side, and the end portion on the large-diameter side is also provided. The taper portion 22 of the second mounting member 14 is superimposed on the outer peripheral surface and vulcanized and bonded. The main rubber elastic body 16 is formed as an integrally vulcanized molded product including the first mounting member 12 and the second mounting member 14.

  Furthermore, a large-diameter recess 28 is formed in the main rubber elastic body 16. The large-diameter recess 28 is a recess that opens on the end surface on the large-diameter side of the main rubber elastic body 16 and has a substantially mortar shape in the reverse direction. In addition, a cylindrical sealing rubber layer 30 protruding downward is integrally formed at the opening peripheral portion of the large-diameter recess 28 in the main rubber elastic body 16, and is formed on the inner peripheral surface of the second mounting member 14. It is fixed.

  Furthermore, a stopper rubber 32 integrally formed with the main rubber elastic body 16 is vulcanized and bonded to the outer peripheral surface and the upper surface of the stopper portion 18 of the first attachment member 12, and the stopper portion 18 is attached to the second attachment member 12. Stopper means for limiting the relative displacement amount of the first mounting member 12 and the second mounting member 14 by abutting with an outer bracket (not shown) fixed to the member 14 via the stopper rubber 32 is configured. It has become so.

  A flexible membrane 34 is attached to the integrally vulcanized molded product of the main rubber elastic body 16. The flexible film 34 is a thin rubber film having a substantially disk shape, and is easily deformable in the thickness direction and has sufficient slack. Further, a fixing member 36 is vulcanized and bonded to the outer peripheral end portion of the flexible film 34. The fixing member 36 is integrally provided with a substantially annular plate-shaped fixing portion 38 and a connecting portion 40 protruding upward from the outer peripheral end portion of the fixing portion 38. The outer peripheral end of the flexible membrane 34 is vulcanized and bonded to the inner peripheral end of the fixing portion 38, and the seal rubber 42 integrally formed with the flexible membrane 34 is attached to the outer peripheral portion of the fixing portion 38. Is vulcanized and bonded.

  The flexible membrane 34 having such a structure is fixed to the lower end portion of the second mounting member 14 by fixing the connecting portion 40 of the fixing member 36 by the caulking piece 26 of the second mounting member 14. It is attached. As a result, the upper opening of the second mounting member 14 is closed by the main rubber elastic body 16, and the lower opening of the second mounting member 14 is closed by the flexible membrane 34. A fluid chamber 44 is formed between the opposing surfaces of the main rubber elastic body 16 and the flexible film 34 and is fluid-tightly separated from the outside. The sealing rubber 42 is compressed between the opposed surfaces of the stepped portion 24 of the second mounting member 14 and the fixing portion 38 of the fixing member 36, so that the fixing member 36 is fluidized against the second mounting member 14. The fluid chamber 44 is tightly assembled, and the fluid tightness of the fluid chamber 44 is ensured.

  Further, the fluid chamber 44 is filled with an incompressible fluid. The incompressible fluid is not particularly limited, and for example, water, alkylene glycol, polyalkylene glycol, silicone oil, or a mixed solution thereof is preferably used. Furthermore, a low-viscosity fluid of 0.1 Pa · s or less is desirable in order to advantageously obtain a vibration-proofing effect based on the fluid flow action described later.

  A partition member 46 is disposed in the fluid chamber 44. The partition member 46 has a thick, substantially disk shape as a whole, and includes an upper partition member 48 and a lower partition member 50.

  The upper partition member 48 is formed of a metal, hard synthetic resin, or the like, and has a thick and large-diameter substantially disk shape. The outer peripheral end portion opens to the outer peripheral surface and has a predetermined length in the circumferential direction. A circumferential groove 52 extending in the length is formed. In addition, a substantially circular communication recess 54 that opens upward and a stepped substantially circular fitting recess 56 that opens downward are formed in the central portion in the radial direction of the upper partition member 48. Further, a first annular groove 58 that opens in the upper bottom surface of the fitting recess 56 is formed in the radially intermediate portion of the upper partition member 48, and the first annular recess is formed at a plurality of locations on the circumference. An upper through hole 60 that penetrates the upper bottom wall portion of the groove 58 in the vertical direction and communicates the first annular groove 58 and the communication recess 54 with each other is formed. In the opening portion of the first annular groove 58, an accommodation groove 62 that is wider than the first annular groove 58 is continuously formed over the entire circumference. Further, a first locking protrusion 64 protruding downward is integrally formed at the opening edge of the first annular groove 58.

  The lower partition member 50 is a hard member similar to the upper partition member 48 and has a substantially disk shape that is thinner and smaller in diameter than the upper partition member 48, and the central portion in the radial direction is upward. A protruding portion is formed thicker than the outer peripheral portion, and a fitting portion 66 protruding downward is integrally formed at the outer peripheral end portion. In addition, the thick annular portion of the lower partition member 50 is formed with a second annular concave groove 68 that opens upward in the radial intermediate portion, and the second annular concave groove 68 at a plurality of locations on the circumference. A lower through hole 70 is formed so as to penetrate the bottom wall of the upper and lower sides. A second locking protrusion 72 protruding upward is integrally formed at the opening edge of the second annular groove 68.

  And the lower partition member 50 is inserted in the fitting recess 56 of the upper partition member 48, and the upper partition member 48 and the lower partition member 50 are piled up and down. In addition, in the state where the upper and lower partition members 48 and 50 are overlapped, the opening of the housing concave groove 62 is covered with the lower partition member 50 to form a housing space 74 that extends in the circumferential direction. The opening of the first annular groove 58 and the opening of the second annular groove 68 both communicate with the accommodation space 74. Thereby, the communication flow path 76 that penetrates the upper and lower partition members 46 includes the first and second annular grooves 58 and 68, the upper and lower through holes 60 and 70, and the accommodation space 74. Has been. Further, an annular arrangement region in the communication flow path 76 is formed by the first and second annular grooves 58 and 68 and the accommodation space 74.

  In addition, an elastic valve member 78 is disposed in an intermediate portion of the communication channel 76 in the channel length direction. The elastic valve member 78 is an annular rubber elastic body. In this embodiment, as shown in FIG. 4, the first elastic body 80 as an elastic protrusion and the second as a buffer protrusion. The elastic body 82 is configured. In addition, the elastic valve member 78 of this embodiment is comprised by the 1st elastic body 80 and the 2nd elastic body 82 which were formed independently separately from each other.

  The first elastic body 80 has a structure in which a valve portion 86 is integrally formed on the outer peripheral side of the inner peripheral clamping portion 84. The inner peripheral clamping part 84 includes an annular first thin support part 88 and a first thick support part 90 projecting upward and downward on the inner peripheral side. In the central portion in the radial direction and the outer peripheral end portion, a seal lip 92 that protrudes on both sides in the thickness direction is integrally formed to protrude. The valve portion 86 is provided so as to protrude from the first thin support portion 88 to the outer peripheral side, and a valve body 94 protruding on both sides in the thickness direction is continuously provided over the entire periphery at the outer peripheral end portion. Yes. The valve body 94 is gradually narrower in the radial direction as it goes to the distal end side, and its outer peripheral surface is a substantially cylindrical surface extending in the axial direction. Further, the valve body 94 is arranged on the outer peripheral side with a predetermined distance from the first thin support portion 88, and between the valve body 94 and the first thin support portion 88, these valve bodies are arranged. A constricted portion 96 that is thinner than both the 94 and the first thin-wall support portion 88 is provided.

  The second elastic body 82 has a structure in which the contact portion 100 is integrally formed on the inner peripheral side of the outer peripheral clamping portion 98. The outer periphery clamping portion 98 includes an annular second thin support portion 102 and a second thick support portion 104 that protrudes upward and downward on the outer peripheral side. The contact part 100 is thicker than the second thin support part 102 and protrudes on both sides in the thickness direction. Further, at the projecting tip portion of the contact portion 100, the inner peripheral surface is a cylindrical surface having a substantially constant inner diameter at the central portion in the thickness direction, and the thickness direction outside at both end portions in the thickness direction. The taper surface 106 is gradually inclined toward the outer periphery as it goes to.

  The elastic valve member 78 is configured by disposing the second elastic body 82 on the outer peripheral side of the first elastic body 80 with a predetermined gap in the radial direction. Further, the first elastic body 80 and the second elastic body 82 are arranged so that the centers in the thickness direction substantially coincide with each other, and the contact portion 100 of the second elastic body 82 is the first elastic body 80. The elastic body 80 is provided at a position facing the base end portion of the valve body 94 (vertical center portion of the valve body 94) in the radial direction. Furthermore, a slit-like flow path that penetrates the elastic valve member 78 up and down is continuous over the entire circumference by utilizing the region (gap) between the opposing surfaces of the first elastic body 80 and the second elastic body 82. Is formed.

  The elastic valve member 78 is disposed between the overlapping surfaces of the upper and lower partition members 48 and 50 and is supported by the upper and lower partition members 48 and 50. In other words, the first elastic body 80 has an inner peripheral clamping portion 84 that is sandwiched between the upper partition member 48 and the lower partition member 50 at the inner peripheral end portion of the accommodation space 74, and is opposed to one side of the communication channel 76. It protrudes from the inner peripheral side wall surface that is a wall surface. In the second elastic body 82, the outer periphery clamping portion 98 is sandwiched between the upper partition member 48 and the lower partition member 50 at the outer peripheral end of the accommodation space 74, and the outer periphery is the other opposing wall surface of the communication channel 76. It protrudes from the side wall surface. Further, the valve portion 86 of the first elastic body 80 and the contact portion 100 of the second elastic body 82 are disposed on the openings of the first and second annular grooves 58 and 68, respectively. A gap between the radial directions of the first and second elastic bodies 80 and 82 is communicated with the first and second annular grooves 58 and 68. Further, the valve element 94 of the valve portion 86 is formed so as to protrude on both sides in the flow path length direction of the communication flow path 76. The contact portion 100 is disposed to face the outside in the radial direction.

  The partition member 46 having such a structure is accommodated in the fluid chamber 44. That is, the partition member 46 is disposed so as to extend in the direction perpendicular to the axis within the fluid chamber 44, and is positioned by being sandwiched between the axially opposed surfaces of the main rubber elastic body 16 and the fixing member 36. , And is supported by the second mounting member 14.

  Thus, by arranging the partition member 46 in the fluid chamber 44, the fluid chamber 44 is divided into two parts up and down across the partition member 46. That is, a pressure receiving chamber 108 in which a part of the wall portion is formed of the main rubber elastic body 16 and an internal pressure fluctuation is caused when vibration is input is formed above the partition member 46. On the other hand, below the partition member 46, a part of the wall portion is formed of the flexible film 34, and an equilibrium chamber 110 in which a volume change is easily allowed by deformation of the flexible film 34 is formed. . The pressure receiving chamber 108 and the equilibrium chamber 110 are filled with an incompressible fluid sealed in the fluid chamber 44.

  Further, the outer peripheral surface of the upper partition member 48 is pressed against the inner peripheral surface of the second mounting member 14 via the seal rubber layer 30, so that the opening on the outer peripheral side of the peripheral groove 52 is the second mounting member 14. A tunnel-like flow path is formed by covering fluidly. One end portion of the tunnel-shaped channel is communicated with the pressure receiving chamber 108 through the upper communication port 112, and the other end portion is communicated with the equilibrium chamber 110 through the lower communication port 114. A first orifice passage 116 that communicates the chamber 108 and the equilibrium chamber 110 with each other is formed using the circumferential groove 52. The first orifice passage 116 has a tuning frequency, which is a resonance frequency of the fluid flow, having a predetermined value by appropriately adjusting the ratio (A / L) of the passage cross-sectional area (A) and the passage length (L). In this embodiment, a low frequency of about 10 Hz corresponding to engine shake is set.

  In addition, the communication channel 76 communicates the pressure receiving chamber 108 and the equilibrium chamber 110 with each other by communicating the upper through hole 60 with the pressure receiving chamber 108 and the lower through hole 70 with the equilibrium chamber 110. ing. Accordingly, the pressure receiving chamber 108 and the equilibrium chamber 110 are communicated with each other through a slit-like flow path formed between the opposing surfaces of the first elastic body 80 and the second elastic body 82, and the slit-like flow The second orifice passage 118 of the present embodiment is configured by the path. The tuning frequency of the second orifice passage 118 is set in the same manner as the first orifice passage 116, and the tuning frequency is adjusted to be higher than that of the first orifice passage 116. In the present embodiment, the tuning frequency of the second orifice passage 118 is set to a medium frequency of about a dozen Hz corresponding to idling vibration. In the present embodiment, a portion (a central portion in the axial direction) in which the inner peripheral surface of the contact portion 100 is a non-inclined substantially cylindrical shape functions as the second orifice passage 118.

  Further, the second orifice passage 118 is switched to the cut-off state when the first elastic body 80 is elastically deformed and abuts against the second elastic body 82 when low frequency large amplitude vibration is input. More specifically, hydraulic pressure is applied to the valve body 94 of the first elastic body 80, and the valve body 94 is displaced in a swinging manner with the constricted portion 96 as a fulcrum, so that the outer peripheral surface of the valve body 94 is The second orifice passage 118 is blocked by contacting the tapered surface 106 of the contact portion 100 of the second elastic body 82.

  In the engine mount 10 having such a structure, the first mounting member 12 is attached to a power unit (not shown) via a first bracket (not shown), and the second mounting member 14 is fixed to the caulking piece 26. By being attached to a vehicle body (not shown) via the bracket 120, it is attached to the vehicle.

  When low-frequency large-amplitude vibration corresponding to an engine shake is input in such a state of being mounted on a vehicle, fluid flow through the first orifice passage 116 is positively generated, and flow such as resonance of the fluid occurs. The anti-vibration effect (high damping effect) based on the action is effectively exhibited.

  When such low-frequency large-amplitude vibration is input, the valve body 94 is elastically deformed due to the relative hydraulic pressure difference between the pressure receiving chamber 108 and the equilibrium chamber 110, and the valve body 94 is swung in accordance with the elastic deformation of the constricted portion 96. By being displaced, it comes into contact with the contact part 100. As a result, the second orifice passage 118 is blocked by the valve element 94 and fluid flow through the second orifice passage 118 is prevented, so that the relative pressure difference between the pressure receiving chamber 108 and the equilibrium chamber 110 is reduced. A sufficient amount of fluid that occurs efficiently and flows through the first orifice passage 116 is ensured. As a result, the anti-vibration effect exhibited by the fluid flow through the first orifice passage 116 can be advantageously obtained, and excellent anti-vibration performance is realized. In this case, since both the valve body 94 and the contact portion 100 are formed of a rubber elastic body, when the second orifice passage 118 is shut off, an abnormal noise due to the contact between the valve body 94 and the contact portion 100 is obtained. Is prevented, and the quietness of the passenger compartment space is ensured.

  Further, the contact portion of the valve body 94 in the contact portion 100 has a tapered surface 106, and the valve body 94 contacts the tapered surface 106 when the second orifice passage 118 is shut off. The contact portion 100 comes into contact with the surface. As a result, the second orifice passage 118 is more reliably shut off and liquid leakage or the like is prevented, so that the desired vibration isolation characteristics can be advantageously obtained.

  When medium frequency small amplitude vibration corresponding to idling vibration is input, the first orifice passage 116 is substantially blocked by anti-resonance, and the valve element 94 is held away from the contact portion 100. Thus, the second orifice passage 118 is brought into communication. As a result, fluid flow through the second orifice passage 118 is induced between the pressure receiving chamber 108 and the equilibrium chamber 110, and a vibration isolation effect (low dynamic spring effect) based on the fluid flow action is effectively exhibited. .

  In addition, when a high-frequency small-amplitude vibration corresponding to traveling noise is input, both the first orifice passage 116 and the second orifice passage 118 are substantially blocked by anti-resonance. Here, since the hydraulic pressure of the pressure receiving chamber 108 and the hydraulic pressure of the equilibrium chamber 110 are exerted on the valve portion 86 and the contact portion 100 of the elastic valve member 78, the valve portion 86 and the contact portion 100 are By slightly deforming up and down in the thickness direction, sealing of the pressure receiving chamber 108 is avoided, and the intended vibration isolation effect (low dynamic spring effect) is effectively exhibited. As is clear from this, when the high frequency small amplitude vibration is input, the valve portion 86 and the contact portion 100 of the elastic valve member 78 function as a movable film. 100 constitutes a hydraulic pressure transmission mechanism for transmitting the hydraulic pressure in the pressure receiving chamber 108 to the equilibrium chamber 110.

  In particular, the valve portion 86 of the present embodiment has a constricted portion 96 that supports the valve body 94 sufficiently thin, so that the minute displacement of the valve body 94 is easily allowed by elastic deformation of the constricted portion 96. It has become. Therefore, the hydraulic pressure transmission action by the elastic deformation of the elastic valve member 78 is efficiently exhibited, and excellent vibration isolation performance is realized.

  In this way, the engine mount 10 has a wider frequency range including not only low-frequency vibration corresponding to engine shake but also medium-frequency vibration corresponding to idling vibration and high-frequency vibration corresponding to running-over noise. An effective anti-vibration effect can be obtained against this vibration.

  In addition, the second orifice passage 118 for obtaining the anti-vibration effect with respect to the medium frequency vibration and the valve mechanism for opening and closing the second orifice passage 118 and the hydraulic pressure absorbing mechanism for obtaining the anti-vibration effect with respect to the high frequency vibration are both elastic valves. The member 78 is configured, and these mechanisms are realized by a small number of parts.

  Further, the blocking of the second orifice passage 118 is realized by contact between the first elastic body 80 and the second elastic body 82, both of which are formed of an elastic body. Therefore, due to the elastic deformation of the first elastic body 80 and the second elastic body 82, the impact force due to the contact is alleviated, and the contact sound is reduced.

  Further, the elastic valve member 78 is formed in an annular shape, and both the inner peripheral end portion and the outer peripheral end portion are supported by the partition member 46. Thereby, the amount of elastic deformation of the elastic valve member 78 due to the action of the hydraulic pressure is limited, and the hydraulic pressure transmission action is sufficiently exerted when the high frequency small amplitude vibration is input, while the low frequency large amplitude vibration is input, By restricting the hydraulic pressure transmission action, the amount of fluid flowing through the first orifice passage 116 is efficiently ensured, and the intended vibration isolation effect is effectively exhibited.

  Further, the second orifice passage 118 has a slit shape formed by using a region between the first elastic body 80 and the second elastic body 82 in the radial direction. A valve element 94 is provided on the inner peripheral edge. Thereby, the opening area of the second orifice passage 118 can be secured sufficiently large while suppressing the protruding height of the valve element 94, and the switching of the second orifice passage 118 to the shut-off state can be stably performed. This can be realized, and a large degree of freedom in tuning of the second orifice passage 118 can be secured.

  In addition, the elastic valve member 78 of the present embodiment is configured by arranging the first elastic body 80 and the second elastic body 82 that are formed independently from each other with a predetermined gap therebetween. This makes it easy to prevent narrowing due to burrs in the second orifice passage 118, dimensional errors, and the like, so that the slit-like second orifice passage 118 can be formed with high dimensional accuracy and the desired vibration isolation. The characteristics can be realized more advantageously. In addition, the second orifice passage 118 can be formed with a small width dimension, and the second orifice passage 118 having a narrow slit shape that can be easily blocked by the valve body 94 can be easily and stably formed. Can be realized.

  As mentioned above, although embodiment of this invention was explained in full detail, this invention is not limited by the specific description. For example, the elastic protrusion and the buffer protrusion are not necessarily separate from each other, and may be integrally formed of, for example, a rubber elastic body.

  Further, the second orifice passage is not necessarily limited to a slit shape continuously extending over the entire circumference, but a circular slit shape, a linear slit shape, a circular shape, a rectangular shape, or the like divided on the circumference. Arbitrary shapes, such as a hole shape penetrating at, may be employed.

  In addition, the elastic valve member is not limited to an annular body that is continuous over the entire circumference in the circumferential direction, and for example, an arc-shaped member or a disk-shaped member divided in the circumferential direction may be employed. Furthermore, the shape of the arrangement region of the elastic valve member in the communication channel can be arbitrarily set according to the shape of the elastic valve member, and is not particularly limited.

  In addition, the support structure by the partition member of the elastic protrusion and the buffer protrusion is not limited to the non-adhesive sandwiched by the partition member, and is fixed to the inner surface of the communication channel wall by means such as adhesion or welding. May be.

  Further, in the above-described embodiment, the elastic protruding piece protrudes from the opposing wall surface on the inner peripheral side of the communication flow path, and the buffer protrusion protrudes from the opposing wall surface on the outer peripheral side of the communication flow path. Are arranged at a predetermined distance on the outer peripheral side of the elastic projection piece. However, for example, the elastic protrusion protrudes from the opposing wall surface on the outer peripheral side of the communication flow path, and the buffer protrusion protrudes from the opposing wall surface on the inner peripheral side of the communication flow path. It may be arranged at a predetermined distance on the inner peripheral side of the piece.

  Moreover, the structure of an elastic protrusion and a buffer protrusion is not limited to the thing of the said embodiment. Specifically, for example, a structure as shown in FIG. 5 may be employed. In other words, the tongue-shaped elastic protrusion 130 protruding from the inner peripheral side wall surface that is one opposing wall surface of the communication channel 76 has a tongue protruding from the outer peripheral side wall surface that is the other opposing wall surface of the communication channel 76. It is also possible to employ a structure in which a pair of buffer projections 132, 132 that are separated in the vertical direction and overlap with each other in the axial projection and arranged so as to be separated from each other in the axial direction. . Accordingly, the second orifice passage 118 is blocked by the elastic protrusion 130 elastically deforming in the thickness direction and coming into contact with one of the pair of buffer protrusions 132, 132. .

  In the structure of FIG. 5, a pair of upper and lower buffer projections 132 are provided, and when the low frequency large amplitude vibration is input, the second orifice passage is applied both when the pressure receiving chamber 108 is pressurized and when the pressure is reduced. 118 is cut off. However, such a structure is merely an example, and for example, only one of the upper and lower buffer protrusions 132 is provided, and the elastic protrusion 130 abuts the buffer protrusion 132, thereby The second orifice passage 118 may be blocked only during either pressurization or decompression. By adopting such a structure, for example, when the hydraulic pressure in the pressure receiving chamber 108 decreases, the second orifice passage 118 is maintained in a communicating state, so that the occurrence of abnormal cavitation noise can be suppressed.

  The application range of the fluid filled type vibration isolator according to the present invention is not limited to the engine mount, but can be applied to a body mount, a subframe mount, a differential mount, and the like. In addition, the present invention is not only applied to a fluid-filled vibration isolator used for automobiles, but is also suitable for a fluid-filled vibration isolator used for motorcycles, railway vehicles, industrial vehicles, and the like. Applied.

10: engine mount (fluid-filled vibration isolator), 12: first mounting member, 14: second mounting member, 16: main rubber elastic body, 34: flexible membrane, 46: partition member, 76: Communication channel, 78: elastic valve member, 80: first elastic body (elastic protrusion), 82: second elastic body (buffer protrusion), 94: valve body, 106: taper surface, 108: pressure receiving chamber , 110: equilibrium chamber, 116: first orifice passage, 118: second orifice passage, 130: elastic protrusion, 132: buffer protrusion

Claims (5)

The first mounting member and the second mounting member having the cylindrical portion are elastically connected by the main rubber elastic body, and a wall is provided on one side of the partition member supported by the second mounting member. A pressure receiving chamber in which a part of the wall is formed of the main rubber elastic body is formed, and an equilibrium chamber in which a part of the wall is formed of a flexible film on the other side across the partition member Are formed, and a fluid-filled vibration isolator in which an incompressible fluid is sealed in the pressure receiving chamber and the equilibrium chamber, and a first orifice passage is formed to communicate the pressure receiving chamber and the equilibrium chamber with each other. In
The partition member is formed with a communication channel that allows the pressure receiving chamber and the equilibrium chamber to communicate with each other, and protrudes from one of the opposing wall surfaces at an intermediate portion in the fluid flow direction of the communication channel. An elastic protrusion including an elastic protrusion disposed in the passage and a buffer protrusion protruding from the other of the opposing wall surfaces at an intermediate portion in the fluid flow direction of the communication flow path and disposed in the communication flow path. While the valve member is configured, a valve body that protrudes in the flow path length direction of the communication flow path and can be displaced in a swinging manner is provided at the protruding tip portion of the elastic protrusion, and the elastic protrusion A second orifice passage is formed to communicate the pressure receiving chamber and the equilibrium chamber with each other using a region between the opposing surfaces of the piece and the buffer protrusion, and the second orifice passage is the first orifice passage. Tuned to a higher frequency than the orifice passage of the Fluid filled type vibration damping device, characterized in that pieces was so that the orifice passage of the second by abutting the the moderate collision portion is elastically deformed is blocked. A region where the elastic valve member is disposed in the communication channel extends in the circumferential direction of the partition member and expands in an annular shape as a whole, and the elastic protrusion is formed on one of an inner peripheral surface and an outer peripheral surface of the disposed region. 2. The fluid filled type vibration damping device according to claim 1, wherein a piece is protruded and the buffer protrusion protrudes on either the inner peripheral surface or the outer peripheral surface of the arrangement region.   The fluid-filled vibration isolator according to claim 1 or 2, wherein the elastic protrusion and the buffer protrusion are separate from each other.   A valve body projecting on both sides in the flow path length direction of the communication flow path is provided at the projecting distal end portion of the elastic projecting piece, and the buffer projecting projecting portion is located at a position facing the base end portion of the valve body. The fluid-filled vibration isolator according to any one of claims 1 to 3.   A valve body projecting in the flow path length direction of the communication flow path is provided at the projecting tip portion of the elastic projection piece, and a taper surface is provided at the projecting tip portion of the buffer projection, The elastic orifice is elastically deformed, and the second orifice passage is blocked by the valve body coming into contact with the tapered surface of the buffer protrusion. Fluid-filled vibration isolator.

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