JP4751740B2 - Fluid filled vibration isolator - Google Patents

Description

  The present invention relates to a fluid-filled vibration isolator that obtains a vibration-proof effect based on the flow action of an incompressible fluid enclosed therein, such as an engine mount, body mount, diff mount, and the like for an automobile. The present invention relates to a fluid-filled vibration isolator that can be suitably employed.

  Conventionally, in a vibration isolator interposed between members constituting a vibration transmission system, it has been proposed to use a vibration isolation effect based on a flow action such as a resonance action of an enclosed incompressible fluid, As one type, a first attachment member attached to one member to be anti-vibration connected and a second attachment member attached to the other member to be anti-vibration connected are separated from each other, and the first and While the second mounting member is connected to each other by the main rubber elastic body, a part of the wall portion is constituted by the main rubber elastic body, and a pressure receiving chamber in which a pressure fluctuation is generated upon vibration input, and a part of the wall portion 2. Description of the Related Art A fluid-filled vibration damping device is known which is formed of a flexible membrane and forms an equilibrium chamber that easily allows volume change, and has an orifice passage that communicates the pressure receiving chamber and the equilibrium chamber with each other. Yes. An example of such a fluid-filled vibration isolator is Patent Document 1 (Japanese Utility Model Laid-Open No. 7-18046).

  In such a fluid-filled vibration isolator, an effective vibration isolating effect can be obtained based on the resonance action of the fluid flowing through the orifice passage, and a static initial load such as a power unit support load can be obtained in the mounted state. Even when a load is applied, the pressure change of the enclosed incompressible fluid can be reduced or avoided based on the volume change of the equilibrium chamber, and the desired vibration isolation effect based on the resonance action of the fluid can be stabilized. For example, it can be advantageously employed in an engine mount for automobiles.

  By the way, in the fluid filled type vibration isolator, the orifice passage is tuned in advance according to the vibration frequency of the main input vibration, and an excellent vibration isolation effect is exhibited against vibrations in a set specific frequency range. It has been known. Such frequency tuning of the orifice passage is realized by appropriately adjusting A / L which is a ratio of passage length: L and passage cross-sectional area: A.

  However, in the generally known fluid-filled vibration isolator, the amplitude dependency of the tuning frequency (resonance frequency) at which the tuning frequency of the orifice passage changes according to the amplitude of the input vibration has been pointed out as a problem. For example, when a fluid-filled vibration isolator is used as an engine mount for an automobile and the orifice passage is tuned to a low frequency range of about 10 Hz so as to exhibit an effective anti-vibration effect against engine shake vibration. Even when engine shake vibrations having the same frequency are input, these input vibrations may have different amplitudes depending on the road surface condition or the like. At that time, when the amplitude increases, the tuning frequency of the orifice passage tends to shift to a low frequency region. Note that this phenomenon is caused by the fact that the amount of deformation of the main rubber elastic body that forms a part of the wall portion of the pressure receiving chamber increases as the amplitude increases, and the spring characteristics change, thereby changing the wall spring characteristics of the pressure receiving chamber. This is considered to be caused by the

  If the tuning frequency of the orifice passage is deviated due to the amplitude dependency of the tuning frequency as described above, there is a possibility that the desired vibration isolation performance based on the fluid action such as the resonance action of the fluid is not stably and effectively exhibited.

  Patent Document 1 discloses a fluid-filled mount in which the tuning frequency of the orifice passage can be arbitrarily changed by changing the flow path length of the orifice passage. However, since the fluid-filled mount disclosed in Patent Document 1 has a structure in which the passage length of the orifice passage is controlled from the outside by an actuator or the like, the amplitude of the input vibration is constantly changed according to the external road surface condition and the like. It may be difficult to cope with such a case, and since it has a complicated structure, a decrease in reliability tends to be a problem.

Japanese Utility Model Publication No. 7-18046

  The present invention has been made in the background as described above, and the problem to be solved is to change the tuning frequency of the orifice passage according to the amplitude of the input vibration by a simple structure. An object of the present invention is to provide a fluid-filled vibration isolator having a novel structure that can reduce or avoid the above.

  Hereinafter, the aspect of this invention made | formed in order to solve such a subject is described. In addition, the component employ | adopted in each aspect as described below is employable by arbitrary combinations as much as possible. Further, aspects or technical features of the present invention are not limited to those described below, but are described in the entire specification and drawings, or an invention that can be understood by those skilled in the art from those descriptions. It should be understood that it is recognized based on thought.

  That is, a feature of the present invention is that the first attachment member attached to one member to be anti-vibration connected and the second attachment member attached to the other member to be anti-vibration connected are made of a main rubber elastic body. A pressure receiving chamber in which a part of the wall part is formed by sealing the main rubber elastic body and enclosed with an incompressible fluid, and a part of the wall part is formed of a flexible film to contain the incompressible fluid. In the fluid-filled vibration isolator provided with the orifice passage for forming the balanced chamber and communicating the pressure receiving chamber and the balance chamber with each other, the pressure receiving chamber opens at least at a part of the wall of the orifice passage. While an opening window is formed, an elastic lid plate member is disposed so as to close the opening window, and the lid plate member is held in a state of covering the opening window by its elasticity, The lid pre The opening side of the orifice passage of the orifice member to the equilibrium chamber is fixedly supported, and the opening side of the lid plate member to the pressure receiving chamber can be displaced relative to the opening window. When the vibration is input, the lid plate member is elastically deformed based on the pressure fluctuation of the pressure receiving chamber to open the opening window, and the orifice passage is opened through the opening window. It is in communication with the room.

  In the fluid-filled vibration isolator having the structure according to the present invention, the lid plate member is elastically deformed according to the amplitude of the input vibration, and the opening amount of the opening window is changed. As a result, the passage length of the orifice passage changes substantially, and the tuning frequency of the orifice passage changes accordingly. Therefore, the deviation of the tuning frequency of the orifice passage according to the magnitude of the amplitude of the input vibration can be canceled out by the change of the tuning frequency due to the shape change of the orifice passage, and the orifice passage based on the amplitude dependency Therefore, it is possible to reduce or avoid the deterioration of the vibration proof performance due to the deviation of the tuning frequency.

  Furthermore, in the present invention, the opening amount of the opening window formed in the wall portion of the orifice passage changes according to the magnitude of the negative pressure generated in the pressure receiving chamber, in other words, the magnitude of the amplitude of the input vibration. Therefore, it is possible to flexibly respond to vibrations of various amplitudes and to exhibit suitable vibration isolation performance. In addition, it is conceivable that the pressure receiving chamber repeatedly increases and decreases pressure according to the amplitude of the input vibration, so that the opening window repeatedly opens and closes due to elastic deformation of the lid plate member. As a result, the anti-vibration performance is broadened and the anti-vibration effect based on the resonance action (flow action) of the fluid that can flow through the orifice passage against vibrations in a wide frequency range is effectively exhibited. It becomes.

  In the fluid-filled vibration isolator according to the present invention, it is desirable that the lid plate member is formed including a metal spring. According to this, it is possible to advantageously ensure the durability of the lid plate member that is repeatedly elastically deformed, and to improve the reliability of the opening / closing operation of the opening window.

  In the fluid-filled vibration isolator according to the present invention, a contact cushioning material that reduces the impact caused by the contact is disposed on at least a part of the contact portion between the lid plate member and the opening peripheral edge of the opening window. The provided structure is preferably employed. According to this, during the closing operation of the lid plate member, the occurrence of sound and vibration due to the lid plate member coming into contact with the opening peripheral edge of the opening window can be advantageously achieved by reducing the impact force by the contact cushioning material. Can be prevented. The contact cushioning material may be partially disposed, for example, at the opening end portion of the lid plate member, etc., but more advantageously to prevent the occurrence of vibration and abnormal noise due to impact at the time of contact. Is preferably disposed on substantially the entire contact portion between the lid plate member and the wall of the orifice passage.

  In the fluid filled type vibration damping device according to the present invention, the orifice passage is formed so as to extend in the circumferential direction of the pressure receiving chamber, and the opening window is formed in a wall portion on the inner peripheral side of the orifice passage. In addition, a structure in which the lid plate member is disposed on the inner peripheral wall of the orifice passage is preferably employed. According to this, by forming the orifice passage so as to extend in the circumferential direction, the passage length of the orifice passage can be advantageously ensured in a limited space, and tuning of the orifice passage can be performed with a high degree of freedom. realizable. Furthermore, by disposing the lid plate member on the wall portion on the inner circumferential side of the orifice passage, the movable region of the lid plate member can be advantageously ensured on the inner circumferential side of the pressure receiving chamber.

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

  First, FIG. 1 shows an automobile engine mount 10 as a first embodiment of the present invention. The engine mount 10 includes a first mounting bracket 12 as a first mounting member and a second mounting bracket 14 as a second mounting member that are spaced apart from each other. The second mounting bracket 14 has a structure in which the main rubber elastic body 16 is elastically connected. The first mounting bracket 12 is mounted on the power unit side of the automobile, while the second mounting bracket 14 is on the body side of the automobile. By attaching the power unit to the body, the power unit is supported to be vibration-proof with respect to the body. In the following description, the vertical direction means the vertical direction in FIG. 1 in principle.

  More specifically, the first mounting bracket 12 has a substantially disk shape as a whole, and a circular block-shaped central protrusion 18 is integrally formed on the upper surface thereof. Further, a mounting screw 20 projecting upward is integrally formed on the central protrusion 18, and the first mounting bracket 12 is attached to the power unit side by the mounting screw 20.

  On the other hand, the second mounting bracket 14 is composed of a cylindrical bracket 22 and a bottom bracket 24 as cylindrical portions. The cylindrical metal fitting 22 has a large-diameter stepped cylindrical shape, the small axial portion 28 is formed on the upper side in the axial direction with the step portion 26 formed in the intermediate portion in the axial direction, and the lower side in the axial direction is large. The diameter portion 30 is used. A flange portion 32 that extends radially outward is integrally formed in the upper opening of the small diameter portion 28. On the other hand, the bottom metal fitting 24 has a large-diameter shallow bottomed cylindrical shape as a whole, and a flange-like portion 34 that extends outward in the radial direction is integrally formed at the peripheral edge of the opening. And the bottom metal fitting 24 is inserted in the large diameter part 30 of the cylindrical metal fitting 22, and the opening peripheral part of the large diameter part 30 is caulked and fixed to the flange-like part 34 of the bottom metal fitting 24, so that the second The mounting bracket 14 is formed with a substantially bottomed cylindrical shape with a deep bottom as a whole. Further, a mounting bolt 36 that protrudes downward is fixed at the center of the bottom of the bottom bracket 24, and the second mounting bracket 14 is attached to the body side of an automobile (not shown) by the mounting bolt 36. It is like that.

  The first mounting bracket 12 is disposed on the substantially same central axis at a predetermined distance above the second mounting bracket 14 in the axial direction, and the first mounting bracket 12 and the second mounting bracket 12 are attached to each other. A main rubber elastic body 16 is interposed between the metal fittings 14. The main rubber elastic body 16 has a generally frustoconical shape with a large diameter as a whole, and has a concave mortar-shaped recess 38 that opens at the end face on the large diameter side. A cylindrical sealing rubber layer 40 is integrally formed on the outer peripheral edge of the large-diameter side end face of the main rubber elastic body 16 so as to extend downward in the axial direction. The first mounting bracket 12 is superimposed on the end surface on the small diameter side of the main rubber elastic body 16 and vulcanized and bonded, while the second mounting bracket 14 is formed on the outer peripheral portion of the large diameter end portion. The small-diameter portion 28 of the tube fitting 22 is vulcanized and bonded in a state where it is embedded. As a result, the opening on the upper side in the axial direction of the cylindrical fitting 22 is fluid-tightly closed by the main rubber elastic body 16. The seal rubber layer 40 formed integrally with the main rubber elastic body 16 has its outer peripheral surface fixed to the inner peripheral surface of the large-diameter portion of the cylindrical metal fitting 22, and the upper inner peripheral surface of the cylindrical metal fitting 22 is the seal rubber layer 40. Covered with.

  In addition, a partition member 42 and a diaphragm 44 as a flexible film are sequentially inserted and arranged in the large-diameter portion 30 of the tubular fitting 22. The partition member 42 is formed of a hard material such as a hard synthetic resin material or a metal material, and has a thick disk shape as a whole. In particular, in the present embodiment, the partition member 42 is formed of a metal material such as an aluminum alloy in consideration of rigidity and the like. In addition, a circular recess 46 opened upward is formed at the central portion of the partition member 42 so as to expand at a substantially constant depth, and the outer peripheral portion is opened to the outer peripheral surface and has a predetermined length in the circumferential direction. A concave groove 48 extending continuously is formed. On the other hand, the diaphragm 44 is formed of a thin rubber film that can be easily deformed, and the outer peripheral portion is slackened so as to be easily deformed. The partition member 42 and the diaphragm 44 are sequentially inserted into the large-diameter portion 30 of the cylindrical metal member 22 so that the outer peripheral portion of the partition member 42 is superimposed on the lower end surface of the main rubber elastic body 16 and the outer peripheral edge of the diaphragm 44. The portion is overlapped with the outer peripheral edge of the lower surface of the partition member 42, and is caulked and fixed at the opening peripheral edge of the large-diameter portion 30 together with the flange-shaped portion 34 of the bottom fitting 24. As a result, the partition member 42 is fixedly supported to the second mounting bracket 14 in a state where the partition member 42 spreads substantially perpendicular to the central axis of the cylindrical bracket 22, and the diaphragm 44 is below the cylindrical bracket 22. It is attached to the second mounting bracket 14 in a state in which the side opening is closed fluid-tightly. The outer peripheral surface of the partition member 42 is superimposed on the cylindrical metal member 22 via a seal rubber layer 40 that is attached to the inner peripheral surface of the cylindrical metal member 22, and the outer peripheral surface of the diaphragm 44 is directly connected to the cylindrical metal member 22. It is superimposed on the inner surface.

  As a result of the assembly of the partition member 42 and the diaphragm 44, the openings on both sides in the axial direction of the tubular fitting 22 are closed fluid-tightly by the main rubber elastic body 16 and the diaphragm 44, and the main rubber elastic body 16 and the diaphragm 44 are opposed to each other. A sealed region is formed between the surfaces that is blocked from the external space. Further, the sealed region is fluid-divided into two by the partition member 42, whereby a part of the wall portion is formed of the main rubber elastic body 16 on the upper side of the partition member 42, and the incompressible fluid is supplied. While the enclosed pressure receiving chamber 50 is formed, an equilibrium chamber 52 in which a part of the wall portion is configured by the diaphragm 44 and incompressible fluid is enclosed is formed below the partition member 42. . As the incompressible fluid sealed in the pressure receiving chamber 50 and the equilibrium chamber 52, for example, water, alkylene glycol, polyalkylene glycol, silicone oil, or the like can be used. In order to effectively obtain the anti-vibration effect based on this, a low-viscosity fluid having a viscosity of 0.1 Pa · s or less is preferably employed.

  Further, the outer peripheral surface of the partition member 42 is overlapped with the inner peripheral surface of the large-diameter portion 30 of the cylindrical metal member 22 over the entire circumference in the circumferential direction via the seal rubber layer 40. As a result, the opening on the outer peripheral side of the groove 48 provided in the partition member 42 is fluid-tightly closed by the seal rubber layer 40, and the outer peripheral portion of the partition member 42 is continuously extended in a circumferential direction over a predetermined length. An extending tunnel-shaped passage is formed. Further, as shown in FIG. 2, one end of the tunnel-shaped passage is connected to the pressure receiving chamber 50 through a communication hole 54 opened in the inner peripheral wall surface of the partition member 42, and the other end is bottom. It is connected to the equilibrium chamber 52 through a communication hole 56 that opens to the wall. As a result, an orifice passage 58 that connects the pressure receiving chamber 50 and the equilibrium chamber 52 to each other is formed using the tunnel-like passage. In the present embodiment, the orifice passage 58 is tuned to a low frequency range of around 10 Hz so that a vibration isolation effect based on the fluid flow action is exhibited against low frequency large amplitude vibration such as engine shake. It has become. Further, as is clear from the above description, the orifice passage 58 extends in the circumferential direction so as to surround the circular recess 46 constituting a part of the pressure receiving chamber 50, and the orifice passage 58 is formed in the pressure receiving chamber 50. Is formed so as to extend in the circumferential direction.

  Here, as shown in FIG. 2, an opening window 60 is formed in a part of the inner peripheral side wall portion of the orifice passage 58. The opening window 60 is formed in the vicinity of the end of the orifice passage 58 on the pressure receiving chamber 50 side, and is formed so as to penetrate the inner peripheral side wall surface of the orifice passage 58 in the radial direction. Further, the opening window 60 is formed with a predetermined length in the circumferential direction. In particular, in this embodiment, the opening window 60 is formed with a length of about ¼ of the orifice passage 58 in the circumferential direction.

  Further, a cover plate metal member 62 as a cover plate member is disposed so as to cover the opening window 60. The lid plate fitting 62 is a metal leaf spring that has elasticity and has a thin plate shape, and is bent so as to follow the curved shape of the inner peripheral side wall portion of the orifice passage 58. Then, the inner peripheral side wall portion of the orifice passage 58 in a state in which the end portion of the lid plate fitting 62 located on the pressure receiving chamber 50 side of the orifice passage 58 can be freely separated from the inner peripheral side wall portion of the orifice passage 58. And the end of the lid plate fitting 62 located on the equilibrium chamber 52 side of the orifice passage 58 is overlaid on the inner peripheral surface of the inner peripheral side wall portion of the orifice passage 58 to open the opening window. It is fixed to the opening edge of 60 by rivets or the like. In short, the lid plate fitting 62 is disposed on the inner peripheral side wall portion of the orifice passage 58 in the partition member 42 in a cantilever state in which one end portion in the circumferential direction is fixedly supported, and the fixed end is not provided. The orifice passage 58 is positioned on the equilibrium chamber 52 side. In particular, in this embodiment, the end of the cover plate fitting 62 located on the pressure receiving chamber 50 side of the orifice passage 58 is urged against the inner peripheral side wall portion of the orifice passage 58 by the elasticity of the cover plate fitting 62 itself. When the vibration is not input, the opening window 60 is held in a state of being covered fluid-tightly by the cover plate fitting 62.

  In the engine mount 10 having such a structure, when vibration in a substantially vertical direction is input between the first mounting bracket 12 and the second mounting bracket 14 in a state of being mounted on an automobile, the pressure receiving chamber 50 Based on the fact that a relative pressure difference is generated between the balance chambers 52, fluid flow through the orifice passage 58 is generated between the two chambers 50 and 52. In particular, when low-frequency large-amplitude vibration such as engine shake with the orifice passage 58 tuned in is inputted, low-frequency large-amplitude vibration such as engine shake is caused based on the resonance action of the fluid flowing through the orifice passage 58. On the other hand, an effective anti-vibration effect is exhibited. In addition, a sufficient urging force is applied to the cover plate fitting 62 so that the opening window 60 can be held fluid-tightly closed during normal vibration input such as engine shake vibration. .

  Further, when a shocking heavy load vibration is input to the engine mount 10 at the time of cranking or sudden acceleration / deceleration of the automobile, the cover plate metal member 62 is elastically deformed, and the opening window 60 is opened / closed. To be sedated.

  That is, when the first mounting bracket 12 and the second mounting bracket 14 are relatively displaced in the axial direction and separated from each other, the pressure in the pressure receiving chamber 50 is lower than the pressure in the equilibrium chamber 52. Become. Here, when a shocking heavy load vibration is input to the engine mount 10, the relative pressure difference between the two chambers 50 and 52 is greater than the urging force with which the lid plate fitting 62 is applied in advance. The lid plate metal 62 is elastically deformed by being pulled toward the pressure receiving chamber 50 by force. As a result, as shown in FIG. 3, the free end of the lid plate fitting 62 (the end located on the pressure receiving chamber 50 side of the orifice passage 58) is separated from the inner peripheral side wall portion of the orifice passage 58 in the direction perpendicular to the axis. Thus, the orifice passage 58 is communicated with the pressure receiving chamber 50 through the opening window 60 at a portion closer to the equilibrium chamber 52 than the communication hole 54 in the length direction. Therefore, the passage length of the orifice passage 58 can be substantially shortened.

  On the other hand, when the first mounting bracket 12 and the second mounting bracket 14 are displaced relative to each other in the axial direction and brought closer to each other, the pressure in the pressure receiving chamber 50 is higher than the pressure in the equilibrium chamber 52. Become. Due to the pressure difference between the two chambers 50, 52, pressure is applied to the lid plate fitting 62 in the direction of pressing against the inner peripheral side wall portion of the orifice passage 58. Therefore, the lid plate fitting 62 is held in a state of fluidly covering the opening of the opening window 60, and the orifice passage 58 has an intended passage length tuned to a low frequency region.

  Here, it is known that the tuning frequency of the orifice passage 58 has an amplitude dependency that gradually shifts to a lower frequency side as the amplitude of the input vibration increases. Further, in the engine mount 10 according to the present embodiment, the elastic deformation of the cover plate metal 62 increases as the amplitude of the input vibration increases, and the opening amount of the opening window 60 increases, so that the amplitude of the input vibration increases. Accordingly, the substantial passage length of the orifice passage 58 is shortened. Therefore, the tuning frequency of the orifice passage 58 set by the ratio (A / L) of the passage length of the orifice passage 58: L and the passage cross-sectional area: A gradually increases as the amplitude of the input vibration increases. Will change. Therefore, the deviation of the tuning frequency of the orifice passage 58 according to the amplitude of the input vibration is canceled out by the change of the tuning frequency due to the change of the passage length of the orifice passage 58, and the difference in the amplitude of the input vibration Regardless, the vibration isolation effect based on the fluid flow through the orifice passage 58 can be effectively exerted against the vibration subject to vibration isolation.

  In particular, the opening window 60 in the present embodiment is formed so as to extend to a certain length in the length direction of the orifice passage 58, and similarly extends in the length direction of the orifice passage 58 to open the opening on the pressure receiving chamber 50 side. The communication hole 54 side is covered with a cover plate fitting 62 fixed to the inner peripheral side wall portion of the orifice passage 58 in a cantilever state so as to be a free end. As a result, the opening and closing of the opening window 60 utilizing the elastic deformation of the cover plate fitting 62 is not switching between the opening state and the closing state as in simple ON / OFF control, but the opening degree of the opening window 60 according to the amplitude of the input vibration. Are provided with multistage or continuous open states. Therefore, the tuning frequency of the orifice passage 58 can be changed with high accuracy in accordance with the amplitude of the input vibration, and a vibration isolation effect based on the resonance action of the fluid flowing through the orifice passage 58 can be advantageously obtained. I can do it.

  Further, when the first mounting member 12 and the second mounting member 14 are relatively displaced so as to be separated from each other in the axial direction, the cover plate member 62 is elastically deformed as described above, and the passage length of the orifice passage 58 is increased. Is changed, and the tuning frequency of the orifice passage 58 is changed. On the other hand, when the first mounting bracket 12 and the second mounting bracket 14 are relatively displaced so as to approach each other in the axial direction, the lid plate bracket Since 62 is held in a state in which the opening window 60 is covered fluid-tightly, the passage length of the orifice passage 58 is maintained at the initial length. Therefore, it may be possible to obtain a vibration isolation effect based on the resonance action of the fluid flowing through the orifice passage 58 in a plurality of or a wide frequency range.

  Further, when a significant negative pressure is generated in the pressure receiving chamber 50, abnormal noise or vibration due to cavitation tends to be a problem. The abnormal noise and vibration due to the cavitation are caused by the pressure inside the pressure-receiving chamber 50 being in a negative pressure state, so that the dissolved gas in the sealed fluid is separated and bubbles are generated, and an explosive micro jet (micro) formed when the bubbles collapse. Jet) is considered to be generated by water hammer pressure being propagated to the first mounting member and the second mounting member and transmitted to the body of the automobile. Furthermore, it has been confirmed that cavitation bubbles are mainly generated in the vicinity of the pressure receiving chamber 50 side opening of the orifice passage 58, and the negative pressure generated in the vicinity of the pressure receiving chamber 50 side opening of the orifice passage 58 is quickly eliminated. This is considered to be effective for reducing or avoiding abnormal noise and vibration caused by cavitation. Here, in the present embodiment, an opening window 60 is formed in the vicinity of the opening of the orifice passage 58 on the pressure receiving chamber 50 side, and a cover plate fitting 62 is disposed so as to close the opening window 60. The lid plate fitting 62 is sucked and opened by the negative pressure in the pressure receiving chamber 50. Therefore, when a significant negative pressure is generated in the pressure receiving chamber 50, the passage length of the orifice passage 58 is shortened, and the fluid flow is advantageously ensured. Therefore, the negative pressure in the vicinity of the opening on the pressure receiving chamber 50 side of the orifice passage 58 is quickly eliminated by the fluid flowing through the orifice passage 58, and the generation of abnormal noise and vibration due to gas phase separation is effectively reduced or reduced. This can be avoided.

  Next, FIG. 4 shows an engine mount 64 as a second embodiment of the present invention. In the following description, members or parts that are substantially the same as those of the first embodiment are denoted by the same reference numerals in the drawings, and the description thereof is omitted.

  In other words, in the engine mount 64 according to the present embodiment, the shock absorbing rubber member 66 serving as the contact shock absorbing material is covered with the outer peripheral surface of the lid plate fitting 62 (the surface on the side overlapped with the inner peripheral side wall portion of the orifice passage 58). It is formed. The shock absorbing rubber member 66 is fixed to a portion of the lid plate metal 62 that overlaps with the opening peripheral edge of the opening window 60 in the inner peripheral side wall of the orifice passage 58, and is substantially rectangular formed of a thin rubber elastic body. It is a frame-shaped member.

  Further, a contact stepped portion 68 is formed in a portion where the shock absorbing rubber member 66 is brought into contact with the inner peripheral side wall portion of the orifice passage 58. The abutting step portion 68 is formed so as to surround the entire periphery of the opening edge of the opening window 60, and the abutting step portion 68 forms a buffer rubber on the inner peripheral side wall portion of the orifice passage 58. The thickness of the portion where the member 66 is overlapped is thinner than the other portion of the inner peripheral side wall portion of the orifice passage 58 by substantially the same dimension as the thickness of the shock absorbing rubber member 66. In the present embodiment, the height dimension of the opening window 60 is made smaller than the height dimension of the inner peripheral side wall portion of the orifice passage 58, and the waist wall formed on the inner peripheral side wall portion of the orifice passage 58 Wall portions of a form such as a leaning wall are positioned above and below the opening window 60, and a sleeve-like wall portion is formed between the opening window 60 and the communication hole 54. As a result, a wall portion that extends in the vertical direction over the entire periphery is formed at the opening periphery of the opening window 60, and the contact stepped portion 68 is formed on the wall portion, whereby the opening periphery of the opening window 60 is formed. A contact stepped portion 68 is formed so as to surround the portion over the entire circumference. Further, in the present embodiment, since the buffer rubber member 66 is formed so as to be overlapped over the entire periphery of the opening peripheral edge of the opening window 60, the contact stepped portion 68 extends over the entire opening window 68. However, the contact stepped portion 68 does not necessarily have to be formed over the entire circumference, and may be formed at a location corresponding to the position where the cushioning rubber member 66 is formed. Furthermore, such a contact stepped portion 68 is not essential, and may be omitted depending on the shape of the cover plate fitting 62 and the shock absorbing rubber member 66.

  The lid metal fitting 62 to which the shock-absorbing rubber member 66 is fixed is assembled to the inner peripheral side wall portion of the orifice passage 58 provided with the contact step portion 68 by rivets, bolts, or the like. Under such an attached state, the shock absorbing rubber member 66 is clamped between the cover plate fitting 62 and the inner peripheral side wall portion of the orifice passage 58 to fluidly seal between the overlapping surfaces of the cover plate fitting 62 and the orifice passage 58. It is sealed. The buffer rubber member 66 is clamped between the lid plate metal 62 and the inner peripheral side wall portion of the orifice passage 58 by a fastening force such as a rivet or a bolt on the fixed end side of the lid plate metal 62. In addition, the free end side of the cover plate fitting 62 is clamped by an urging force based on the elasticity of the cover plate fitting 62 itself.

  In the engine mount 64 having the structure according to this embodiment, the lid plate fitting 62 is generated between the lid plate fitting 62 and the inner peripheral side wall portion of the orifice passage 58 when the lid plate fitting 62 closes the opening window 60. It is possible to reduce or avoid hitting sound and impact. Further, by providing the shock absorbing rubber member 66 between the opposed surfaces of the lid plate fitting 62 and the inner peripheral side wall of the orifice passage 58, the closed state of the opening window 60 can be advantageously realized with higher fluid tightness. I can do it.

  As mentioned above, although some embodiment of this invention has been described, this is an illustration to the last, Comprising: This invention is not limited at all by the specific description in this embodiment.

  For example, in the first and second embodiments, the opening window 60 is formed on the inner peripheral side wall portion of the orifice passage 58, and the cover plate fitting 62 disposed so as to cover the opening window 60 is perpendicular to the axis. It opens and closes depending on the direction. However, the formation position of the opening window does not necessarily have to be the inner peripheral side wall portion of the orifice passage 58. Specifically, for example, an opening window is formed as a through hole opening in the upper wall portion of the orifice passage 58, and the lid plate metal fitting 62 is overlapped on the upper wall portion of the orifice passage 58 so as to cover the opening window. It may be arranged. According to this, it is not necessary to use the central portion of the partition member 42 as an opening / closing space for the cover plate fitting 62, and a movable plate that absorbs the hydraulic pressure is disposed using the circular recess 46. It is also possible to improve the anti-vibration performance against vibrations in the high frequency range. As is clear from the above structure, the lid plate metal fitting need not be a curved plate shape as shown in the first and second embodiments, but may be a flat plate shape or the like. .

  In addition, as shown in the first and second embodiments, in order to stably realize excellent vibration isolation performance with respect to normal vibration isolation target vibration, the lid plate metal fitting 62 is provided with an opening peripheral edge ( Although it is desirable that the urging force is applied in advance so as to be pressed against the inner peripheral side wall portion of the orifice passage 58, such an urging force is not essential. For example, the lid plate fitting 62 may be superimposed on the inner peripheral side wall portion of the orifice passage 58 without being pressed. The lid plate metal 62 is overlapped with the wall portion of the orifice passage 58 so as to close the opening window 60 when vibration is not input.

  Further, the lid metal fitting 62 that is repeatedly elastically deformed in the shearing direction is preferably formed of a metal material such as stainless steel from the viewpoint of durability or the like, but is not limited thereto, for example, rubber elasticity It is also possible to employ other materials such as a body.

  Further, the buffer rubber member 66 shown in the second embodiment is not construed as being limited in any way by the specific description in the embodiment. In other words, the shock absorbing rubber member is interposed on the entire contact surface between the cover plate metal fitting and the inner peripheral side wall portion of the orifice passage in order to reduce the impact caused by the contact between the cover plate metal fitting and the wall portion of the orifice passage. However, it is not always necessary to be disposed on the entire contact surface, and may be partially disposed. Specifically, for example, even if the frame-shaped shock absorbing rubber member 66 shown in the second embodiment is made narrower and attached to the contact surface of the lid plate metal fitting 62 in a shape like a ridge. Alternatively, the cushioning rubber member may be disposed only at the free end side end portion of the lid plate fitting 62 where the separation distance from the inner peripheral side wall portion of the orifice passage 58 is the largest. In the second embodiment, the contact stepped portion 68 is formed so as to extend over the entire periphery of the opening peripheral portion of the opening window 60 where the buffer rubber member 66 is superimposed. The abutting stepped portion 68 is not essential and may not be formed. As described above, for example, when the shock absorbing rubber member is disposed only on the free end side of the lid plate fitting 62, You may form only in the part with which this buffer rubber member is piled up.

  Further, according to the present invention, the first mounting member and the second mounting member arranged concentrically or eccentrically with each other are connected by the main rubber elastic body, and the first mounting member and the second mounting member are connected. A hollow space extending through the members in the axial direction is formed over a substantially half circumference in the circumferential direction, and a wall is formed by the main rubber elastic body between the first mounting member and the second mounting member. And a pressure receiving chamber in which a pressure change is generated when a vibration is input is formed, and a flexible film is disposed in the empty space, and the flexible film and the second mounting member Are formed with an equilibrium chamber in which volume change is easily allowed, an incompressible fluid is sealed in the pressure receiving chamber and the equilibrium chamber, and an orifice passage that communicates the pressure receiving chamber and the equilibrium chamber with each other. It can also be applied to fluid filled vibration isolator It is a function. When the present invention is applied to such a fluid-filled vibration isolator, the orifice passage extends so as to meander along the wall of the pressure receiving chamber or extends over a length of one or more circumferences in the circumferential direction. It is desirable to employ a material for the orifice passage so that an opening window can be formed in a part of the wall portion of the orifice passage, and a cover plate can be provided so that the passage of the orifice passage according to the amplitude of the input vibration can be provided. A change in length can be realized.

  In the first and second embodiments, specific examples of applying the present invention to the fluid-filled vibration isolator having one orifice passage are shown, but a plurality of orifice passages are provided. Of course, the present invention can also be applied to a fluid-filled vibration isolator. When the present invention is applied to a fluid-filled vibration isolator having a plurality of orifice passages, an opening window may be formed in each orifice passage, and a cover plate metal fitting may be provided. An opening window may be formed for one or some of the passages, and a cover plate fitting may be provided.

  In addition, in the first or second embodiment, specific examples of the present invention applied to an engine mount for automobiles have been shown. However, the present invention is not limited to body mounts for automobiles or various types other than automobiles. Any of the vibration isolator used in the apparatus can be advantageously applied.

  In addition, although not enumerated one by one, the present invention can be carried out in a mode to which various changes, modifications, improvements and the like are added based on the knowledge of those skilled in the art. It goes without saying that all are included in the scope of the present invention without departing from the spirit of the present invention.

It is a longitudinal cross-sectional view which shows the engine mount for motor vehicles as 1st embodiment of this invention, Comprising: The II sectional view taken on the line in FIG. The II-II sectional view taken on the line of the engine mount in FIG. It is the III-III sectional view taken on the line of the engine mount in FIG. 1, Comprising: The figure which shows the open operation state of a cover plate metal fitting. FIG. 4 is a cross-sectional view showing an automobile engine mount as a second embodiment of the present invention, corresponding to FIG. 2.

Explanation of symbols

10 engine mount, 12 first mounting bracket, 14 second mounting bracket, 16
Rubber elastic body of main body, 50 pressure receiving chamber, 52 equilibrium chamber, 58 orifice passage, 60 opening window, 62 lid plate metal fitting, 66 shock absorbing rubber member

Claims (4)

A wall portion is formed by connecting a first mounting member attached to one member to be anti-vibrated and a second attachment member attached to the other member to be anti-vibrated and connected by a main rubber elastic body. And a pressure receiving chamber in which an incompressible fluid is enclosed, and a wall portion in which a part of the wall is formed of a flexible film form an equilibrium chamber in which the incompressible fluid is enclosed. In a fluid-filled vibration isolator having an orifice passage that allows the chamber and the equilibrium chamber to communicate with each other,
An opening window that opens to the pressure receiving chamber is formed in at least a part of the wall of the orifice passage, and an elastic lid plate member is disposed so as to close the opening window. While being held in a state of covering the opening window by its elasticity, the opening side to the equilibrium chamber of the orifice passage in the lid plate member is fixedly supported, and the pressure receiving force in the lid plate member The opening side to the chamber is configured to be relatively displaceable with respect to the opening window, and the lid plate member is elastically deformed based on the pressure fluctuation of the pressure receiving chamber at the time of vibration input. A fluid-filled vibration damping device, wherein the opening window is opened, and the orifice passage is communicated with the pressure receiving chamber through the opening window.   The fluid-filled vibration isolator according to claim 1, wherein the lid plate member includes a metal spring.   The fluid-filled type according to claim 1, wherein a contact cushioning material that reduces an impact caused by contact is disposed on at least a part of a contact portion between the lid plate member and the opening peripheral edge of the opening window. Anti-vibration device. The orifice passage is formed so as to extend in the circumferential direction of the pressure receiving chamber, the opening window is formed in the inner peripheral wall portion of the orifice passage, and the inner peripheral wall portion of the orifice passage The fluid-filled vibration isolator according to any one of claims 1 to 3, wherein the lid plate member is disposed on the lid.

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