JP5060971B2 - Fluid-filled vibration isolator and its operation control method - Google Patents

Description

  The present invention relates to an anti-vibration device that is interposed between anti-vibration target members and supports the anti-vibration connections or anti-vibration of the anti-vibration target members to each other, and in particular, the flow action of an incompressible fluid sealed inside. The present invention relates to a fluid-filled vibration isolator capable of exhibiting an anti-vibration effect and an operation control method thereof.

  Conventionally, a pressure receiving chamber in which an incompressible fluid is sealed and a balance are installed as a type of a vibration isolator which is interposed between members to be vibration-isolated to mutually support the vibration isolation connection or vibration isolation. 2. Description of the Related Art There is known a fluid-filled vibration isolator that has a chamber and an orifice passage that allows the two chambers to communicate with each other and uses a vibration-proof effect based on the flow action of the sealed fluid. In addition, in order to obtain an effective anti-vibration effect against vibrations of a wider frequency, a switching type fluid-filled anti-vibration device capable of switching the anti-vibration characteristics according to the frequency of the vibration in question is also proposed. For example, there is an air pressure switching type fluid-filled vibration isolator disclosed in Patent Document 1 (Japanese Patent Laid-Open No. 2005-233242).

  By the way, in the fluid-filled vibration isolator, when vibration of a specific frequency tuned in the orifice passage is input, the vibration isolating effect based on the fluid flow action is exhibited, while the vibration frequency is higher than the tuning frequency. When vibration is input, there is a problem that the dynamic spring constant is remarkably increased due to the antiresonant action of the fluid flowing through the orifice passage, and the vibration isolation performance is deteriorated.

  In the fluid-filled vibration isolator described in Patent Document 1 in which the vibration isolating characteristics can be switched, substantially the same air pressure is exerted on the first working air chamber and the second working air chamber. Therefore, for example, when a negative pressure is exerted on the first working air chamber and the second orifice passage is communicated, a negative pressure is also exerted on the second working air chamber and the movable partition. The member is constrained. Therefore, when vibration with a frequency higher than the tuning frequency of the second orifice passage is input, the anti-resonant action of the fluid flowing through the second orifice passage causes the vibration-proof performance due to the high dynamic spring. There was a possibility that the decrease would be a problem.

JP 2005-233242 A

  Here, the present invention has been made in the background as described above, and the problem to be solved is that the vibration control characteristics can be switched and controlled with a higher degree of freedom. Improved structure fluid that suppresses the increase in dynamic spring constant due to the anti-resonant action of the fluid flowing through the passage and can reduce the deterioration of the vibration isolation performance caused by the anti-resonant action of the fluid. An object of the present invention is to provide an enclosed vibration isolator and an operation control method thereof.

  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, in the present invention, the first mounting member and the cylindrical second mounting member are spaced apart, and the first mounting member and the second mounting member are elastically connected to each other by the main rubber elastic body. A pressure receiving chamber in which a part of the wall part is composed of the main rubber elastic body on both sides of the partition member supported by the second mounting member and a part of the wall part are allowed. Equilibrium chambers composed of flexible membranes were formed, incompressible fluid was enclosed in the pressure receiving chambers and the equilibrium chambers, and an orifice passage was formed to communicate the pressure receiving chambers and the equilibrium chambers with each other. In the fluid filled type vibration damping device, the orifice passage includes a low-frequency orifice passage that communicates the pressure-receiving chamber and the equilibrium chamber, and a low-frequency orifice passage that communicates the pressure-receiving chamber and the equilibrium chamber with each other. Including a medium frequency orifice passage tuned to a high frequency, The intermediate frequency orifice passage is blocked by the valve body being pressed by the urging means against the opening of the intermediate frequency orifice passage to the equilibrium chamber. By providing one working air chamber and applying a negative pressure to the first working air chamber, the valve body is resisted against the urging force of the urging means to the equilibrium chamber of the medium frequency orifice passage. A negative pressure type actuator that is spaced apart from the opening of the negative pressure actuator and communicates the medium frequency orifice passage, and the first working air chamber of the negative pressure type actuator is connected to the negative pressure source and the atmosphere by the first air pressure switching means. As a result, the valve body is driven and the medium frequency orifice passage is switched between a communication state and a shut-off state, while a part of the wall portion has a pressure fluctuation. Suck A secondary liquid chamber is formed which is composed of a wall and encloses an incompressible fluid, and the pressure receiving chamber and the secondary liquid chamber communicate with each other and are tuned to a higher frequency than the medium frequency orifice passage. A high-frequency orifice passage is formed, and a second working air chamber formed on the opposite side of the sub liquid chamber with the pressure fluctuation absorbing wall portion sandwiched between the second liquid air chamber and the negative pressure source by the second air pressure switching means The pressure fluctuation absorbing wall portion can be switched between a suction restraint state and a deformation-permitted state due to negative pressure by being selectively held in communication with the atmosphere. The two air pressure switching means are controlled to be switched independently of each other by the switching control means, and the switching control means is configured to operate under a vibration input condition in a frequency range higher than the resonance frequency of the high frequency orifice passage. A mode in which the first air pressure switching means is operated in a mode in which the first working air chamber of the negative pressure actuator is connected and held in the atmosphere, and the second working air chamber is connected and held in a negative pressure source. And operating the second air pressure switching means .

In the fluid-filled vibration isolator having the structure according to the present invention, the first air pressure switching means for selectively maintaining the first working air chamber in communication with the negative pressure source and the atmosphere, and the second action Second air pressure switching means for selectively keeping the air chamber in communication with the negative pressure source and the atmosphere can be controlled independently of each other. As a result, the switching of the pressure exerted on the first working air chamber and the switching of the pressure exerted on the second working air chamber can be performed at different timings. Therefore, the vibration isolation characteristics can be switched with a higher degree of freedom by appropriately controlling the combination of the pressure exerted on the first working air chamber and the pressure exerted on the second working air chamber.

In addition, by appropriately switching the pressure of the first working air chamber and the pressure of the second working air chamber according to the vibration frequency that is a problem in the input vibration, anti-resonance of the fluid that flows through the orifice passage It is also possible to suppress the deterioration of the dynamic spring characteristics due to the action.
Furthermore, according to the present invention, the atmospheric pressure is applied to the first working air chamber in a situation where vibration in a frequency range higher than the tuning frequency of the high frequency orifice passage is input, so that the intermediate frequency orifice passage is While being in the shut-off state, a negative pressure is exerted on the second working air chamber, whereby a suction force toward the second working air chamber side is exerted on the pressure fluctuation absorbing wall portion, and the pressure fluctuation absorbing wall portion is Be bound. Therefore, by restraining the pressure fluctuation absorbing wall portion, a relative pressure difference cannot be generated between the pressure receiving chamber and the sub liquid chamber, and fluid flow through the high frequency orifice passage is prevented. As a result, it is possible to effectively prevent the vibration-proof performance from being lowered by the high dynamic spring based on the anti-resonant action of the fluid flowing through the high-frequency orifice passage.

  In the fluid filled type vibration damping device according to the present invention, preferably, the low frequency orifice passage is tuned to a frequency corresponding to an engine shake of an automobile, and the medium frequency orifice passage is adapted to idling vibration of the automobile. The frequency is tuned to a corresponding frequency, and the high-frequency orifice passage is tuned to a frequency corresponding to the traveling noise of an automobile.

  According to this, it is possible to exhibit excellent vibration-proof performance with respect to vibrations in a plurality of different frequency ranges in which each orifice passage is tuned. In particular, by setting the tuning frequency of each orifice passage to a frequency corresponding to the vibration of an engine shake or idling of an automobile, or a traveling noise, a fluid-filled type anti-reflection suitable for use as an engine mount for an automobile, for example. A vibration device can be realized.

  Further, in the fluid filled type vibration damping device according to the present invention, the pressure fluctuation absorbing wall portion is provided on a hard central movable plate portion and an outer peripheral side of the central movable plate portion, and elastic deformation is easily allowed. The outer peripheral movable film portion is provided, and the central movable plate portion and the outer peripheral movable film portion are disposed so as to be allowed to be displaced or deformed. It is desirable that a high-frequency orifice passage is formed and a filter orifice tuned in a higher frequency region than the high-frequency orifice passage is formed at a position corresponding to the central movable plate portion.

  If such a structure is adopted, a relative pressure difference is generated between the pressure receiving chamber and the sub liquid chamber due to the elastic deformation of the outer peripheral movable film portion, and the fluid passing through the high-frequency orifice passage is based on the pressure difference. The flow is effectively generated. Therefore, an anti-vibration effect based on the resonance action of the fluid flowing between the pressure receiving chamber and the sub liquid chamber through the high frequency orifice passage is effectively exhibited.

  Moreover, by providing a filter orifice tuned to a frequency higher than that of the high-frequency orifice passage at a position corresponding to the central movable plate portion that absorbs a minute amplitude vibration having a frequency higher than the tuning frequency of the high-frequency orifice passage by a minute displacement, Even when vibrations in a frequency range higher than the tuning frequency of the high-frequency orifice passage are input, the dynamic spring constant can be prevented from significantly increasing based on the fluid pressure absorbing action of the central movable plate, and a wider frequency range can be obtained. It is possible to obtain an effective anti-vibration effect over the entire area.

In the fluid-filled vibration isolator according to the present invention, the switching control means may be configured such that the switching control means includes the first actuator of the negative pressure actuator under a vibration input situation in a frequency range higher than a resonance frequency of the medium frequency orifice passage. the first pneumatic switching means together allowed to work moving the manner of connecting and retaining the working air chamber to a negative pressure source, said second pneumatic switching means the second working air chamber in a manner that retains connected to the atmosphere it may be allowed to work dynamic.

  Thus, under the vibration input situation in a frequency range higher than the tuning frequency of the medium frequency orifice passage, negative pressure is exerted on the first working air chamber, so that the medium frequency orifice passage is brought into communication. When atmospheric pressure is exerted on the second working air chamber, minute displacement or deformation of the pressure fluctuation absorbing wall portion is allowed. Then, based on the fluid pressure absorbing action exerted by the displacement or deformation of the pressure fluctuation absorbing wall, the internal pressure fluctuation induced in the pressure receiving chamber is reduced, and the fluid is sealed due to the anti-resonance of the medium frequency orifice passage. An increase in the dynamic spring constant of the vibration isolator can be suppressed. Accordingly, it is possible to effectively prevent the vibration-proof performance from being lowered due to the anti-resonant action of the medium frequency orifice passage.

Further, the first air pressure is configured such that the switching control means connects and holds the first working air chamber of the negative pressure actuator in the atmosphere under vibration input conditions in the resonance frequency region of the low frequency orifice passage. the switching means together with the allowed to work movement, the second of the second pneumatic switching means working air chamber in a manner that connects held to a negative pressure source may be allowed to create dynamic and.

  According to this, when the atmospheric pressure is exerted on the first working air chamber, the intermediate frequency orifice passage is switched to the cutoff state by the valve body, and the pressure fluctuation induced in the pressure receiving chamber is balanced through the intermediate frequency orifice passage. It can be prevented from being escaped to the room. Further, a negative pressure is exerted on the second working air chamber, and the pressure fluctuation absorbing wall portion is restrained by a negative suction force, whereby the high-frequency orifice passage is switched to a substantially cut-off state, and the pressure receiving chamber Can be prevented from being released to the secondary liquid chamber through the high-frequency orifice passage. Therefore, the amount of fluid allowed to flow between the pressure receiving chamber and the equilibrium chamber through the low frequency orifice passage can be advantageously ensured, and the vibration isolation effect based on the fluid flow through the low frequency orifice passage can be obtained more effectively. I can do it.

On the other hand, according to the present invention, (i) the switching control means keeps the first working air chamber of the negative pressure actuator connected to the atmosphere under vibration input conditions in the resonance frequency range of the low frequency orifice passage. And (ii) an operation control for operating the second air pressure switching means to operate the first air pressure switching means in a mode and to connect and hold the second working air chamber to a negative pressure source. In a mode in which the switching control means connects and holds the first working air chamber of the negative pressure type actuator to a negative pressure source under vibration input conditions in a frequency range higher than the resonance frequency of the frequency orifice passage. And (iii) the high frequency orifice, wherein the air pressure switching means is operated, and the second air pressure switching means is operated in such a manner that the second working air chamber is connected and held in the atmosphere. In a mode in which the switching control means connects and holds the first working air chamber of the negative pressure actuator in the atmosphere under vibration input conditions in a frequency range higher than the resonance frequency of the road, the first air pressure switching means together allowed to operate and an actuating control which allowed to operate said second pneumatic switching means in a manner that the connecting and retaining the said second working air chamber to a negative pressure source, including any one of claims 1 to 3 The operation control method of the fluid filled type vibration damping device described in the above item is also characterized.

  In such an operation control method of the fluid filled type vibration damping device according to the present invention, by adopting the operation control method described in (i), the internal pressure of the pressure receiving chamber is changed to the equilibrium chamber or the high frequency orifice passage through the medium frequency orifice passage and the high frequency orifice passage. By preventing escape to the secondary liquid chamber, it is possible to more effectively obtain a vibration isolation effect based on the fluid action of the fluid that is caused to flow through the low frequency orifice passage.

  Further, by adopting the operation control method described in (ii), it is possible to suppress an increase in the dynamic spring constant due to the antiresonant action of the fluid that flows through the medium frequency orifice passage. Therefore, it is possible to prevent the vibration-proof performance from being extremely lowered even when vibration is input in a frequency range higher than the tuning frequency of the medium frequency orifice passage and lower than the tuning frequency of the high frequency orifice passage.

  Furthermore, by adopting the operation control method described in (iii), the dynamic spring constant of the fluid-filled vibration isolator can be significantly increased by the anti-resonant action of the fluid flowing through the high-frequency orifice passage. Can be prevented. Therefore, even when vibration in a frequency range higher than the tuning frequency of the high-frequency orifice passage is input, it is possible to suppress a decrease in vibration-proof performance.

Note that the Te present invention method smell, the (i), (ii), is carried out the control in three combinations of (iii). Specifically, for example, at the time of vibration input, a means for specifying vibrations to be particularly vibration-proof is provided. choose corresponds to one, depending on the frequency of the vibration to be damped is selected, the (i), (ii), and selects one of three operating control how the (iii) To be adopted. At that time, as a means for identifying the vibration to be damped, it is possible to employ a vibration sensor that directly detects the vibration in the vibration suppression target in real time, but in addition, for example, in an automobile engine mount, Based on sensing data such as travel speed, engine speed, transmission gear selection, roll degree, acceleration / deceleration degree, etc. Thus, it is also possible to employ map control or the like that preferentially determines the vibration frequency of the body to be shaken.

  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 automotive engine mount 10 as a first embodiment of a fluid filled type vibration damping device according to the present invention. The engine mount 10 includes a mount body 11, and the mount body 11 includes a first mounting bracket 12 as a first mounting member and a second mounting bracket 14 as a second mounting member. The rubber elastic bodies 16 are elastically connected to each other. The first mounting bracket 12 is attached to a power unit (not shown) which is one member to be vibration-proof connected, and the second mounting bracket 14 is attached to a vehicle body (not shown) which is the other member to be vibration-proof connected. As a result, the power unit is connected to the vehicle body in a vibration-proof manner. In the following description, the up and down direction means the up and down direction in FIG. 1 which is the main vibration input direction in principle. Further, FIG. 1 shows an engine mount 10 that is not attached to a vehicle, and a shared load of the power unit is exerted in the axial direction (up and down in FIG. 1) by being attached to the vehicle.

  More specifically, the first mounting bracket 12 is a highly rigid member made of iron, aluminum alloy, or the like, and has a substantially truncated cone shape in the reverse direction in the present embodiment. In addition, the first mounting bracket 12 is integrally formed with a mounting bolt 18 that protrudes upward at the radial center portion thereof.

  On the other hand, the second mounting bracket 14 is a highly rigid member formed of the same metal material as the first mounting bracket 12 and has a thin cylindrical shape with a large diameter. Further, an inner flange-shaped step portion 20 that is bent inward in the radial direction is integrally formed at the upper end portion in the axial direction of the second mounting bracket 14 and is directed upward from the inner peripheral edge portion of the step portion 20. A taper portion 22 that extends out is integrally formed. The tapered portion 22 has a cylindrical shape that gradually expands upward, and an upper end edge of the tapered portion 22 is integrally formed with a contact flange portion 24 that extends in the direction perpendicular to the axis toward the outer peripheral side. Yes.

  And the 1st mounting bracket 12 and the 2nd mounting bracket 14 are arrange | positioned on the same central axis, and with respect to the upper side opening part of the 2nd mounting bracket 14 by which the 1st mounting bracket 12 was made into the cylindrical shape. The first mounting bracket 12 and the second mounting bracket 14 are connected to each other by a main rubber elastic body 16.

  The main rubber elastic body 16 is a rubber elastic body having a generally frustoconical shape with a large thickness and a large diameter as a whole, and has a large-diameter recess 26 that opens to the end surface on the large-diameter side. The first mounting bracket 12 is inserted into the small diameter side end of the main rubber elastic body 16 and vulcanized and bonded, and the outer peripheral surface of the large diameter side end of the main rubber elastic body 16 is the second mounting metal. 14 are overlapped and vulcanized and bonded to the inner peripheral surface of the taper portion 22. Thereby, the main rubber elastic body 16 is interposed between the first mounting bracket 12 and the second mounting bracket 14, and the first mounting bracket 12 and the second mounting bracket 14 are connected to the main rubber elastic body 16. And the upper opening of the second mounting bracket 14 is fluid-tightly closed by the main rubber elastic body 16. In the present embodiment, the main rubber elastic body 16 is formed as an integrally vulcanized molded product integrally including the first mounting bracket 12 and the second mounting bracket 14.

  Further, the main rubber elastic body 16 is integrally formed with a seal rubber layer 28 extending downward from the outer peripheral edge of the main rubber elastic body 16. The seal rubber layer 28 is formed of a rubber elastic body having a thin and large-diameter substantially cylindrical shape, and is formed on the inner peripheral surface of the second mounting bracket 14, so that the inner peripheral surface of the second mounting bracket 14 is formed. Is covered to the middle part in the axial direction.

  In addition, a diaphragm 30 as a flexible film is attached to the second mounting member 14. Diaphragm 30 is formed of a rubber elastic body having a generally thin disk shape as a whole, and has a central valve portion 32 as a valve body having a relatively thick plate at the center. The outer peripheral portion has sufficient deflection in the axial direction so that elastic deformation is easily allowed. Further, an annular fixing portion 34 is integrally formed on the outer peripheral edge portion of the diaphragm 30, and an annular fixing fitting 36 is vulcanized and bonded to the fixing portion 34. Note that the diaphragm 30 in the present embodiment is formed as an integrally vulcanized molded product provided with a fixing metal fitting 36.

  The diaphragm 30 is inserted from the lower opening of the second mounting bracket 14 and is disposed in the lower end portion of the second mounting bracket 14, and is eight-way throttled with respect to the second mounting bracket 14. By being subjected to diameter reduction processing such as, it is fixed to the second mounting bracket 14. As a result, the lower opening of the second mounting bracket 14 is covered with the diaphragm 30 and is fluid-tightly closed.

  In addition, the upper opening of the second mounting bracket 14 is closed by the main rubber elastic body 16 and the lower opening of the second mounting bracket 14 is closed by the diaphragm 30. 14 is formed between the main rubber elastic body 16 and the diaphragm 30 on the inner peripheral side thereof in the axial direction.

  Furthermore, incompressible fluid is sealed in the fluid sealing region 38. The incompressible fluid to be enclosed is not particularly limited, and for example, water, alkylene glycol, polyalkylene glycol, silicone oil, a mixed solution thereof, or the like can be appropriately employed. In particular, as the sealed fluid, it is desirable to employ a low-viscosity fluid having a viscosity of 0.1 Pa · s or less in order to advantageously obtain an anti-vibration effect based on the resonance action of the fluid through the orifice passage described later.

  A partition member 40 is accommodated in the fluid sealing region 38. As shown in FIGS. 1 to 3, the partition member 40 has a substantially thick and large-diameter disk as a whole, and includes a partition member main body 42 and a lid fitting 44.

  The partition member main body 42 is formed of a metal material, a hard synthetic resin material, or the like, and has a thick, substantially disk shape as shown in FIG. In addition, a circular recess 46 that opens toward the upper end surface is formed at the center portion in the radial direction of the partition member main body 42, and a communication recess 48 that opens at the lower end surface is formed. Further, a central recess 50 opening upward is formed at the center of the bottom wall of the circular recess 46. In the present embodiment, the circular recess 46, the communication recess 48, and the central recess 50 are all circular recesses.

  A circumferential groove 52 is formed on the outer peripheral edge of the partition member main body 42. The circumferential groove 52 is a concave groove that opens to the outer peripheral surface of the partition member main body 42 and extends with a predetermined length. In the present embodiment, the circumferential groove 52 is folded back in the circumferential direction and extends with a length of less than two rounds. Further, as shown in FIGS. 1 to 3, one end of the circumferential groove 52 is connected to the communication recess 48 through a communication path 54 extending in the radial direction.

  A plurality of locking projections 56 projecting upward are formed on the outer peripheral portion of the partition member main body 42. The locking projections 56 have a small-diameter columnar shape, and in this embodiment, as shown in FIG. 4 and the like, a pair is formed at positions opposed in one radial direction.

  On the other hand, as shown in FIGS. 1 and 5 and the like, the lid fitting 44 has a thin and large-diameter substantially disk shape, and is formed of a metal material having sufficient rigidity. Moreover, the lid metal fitting 44 has a step in the radial intermediate portion, and the outer peripheral side sandwiching the step is positioned higher than the inner peripheral side sandwiching the step, so that the central portion as a whole is recessed. It has a disc shape. Further, the lid fitting 44 is formed with a small-diameter locking hole 58 on the outer peripheral side across the step. The locking hole 58 is a small-diameter circular hole formed at a position corresponding to the locking protrusion 56 in the partition member main body 42, and in the present embodiment, a pair of locking holes are positioned at positions facing each other in one radial direction. 58, 58 are formed.

  The lid member 44 is superimposed on the partition member main body 42 from above and assembled to each other, whereby the partition member 40 in the present embodiment is configured. In the present embodiment, the locking protrusion 56 that protrudes upward from the partition member main body 42 is inserted into the locking hole 58 that is formed through the lid fitting 44, so that the partition member main body 42 The lid fittings 44 are aligned with each other in the circumferential direction.

  The partition member 40 having such a structure is accommodated in a fluid sealing region 38 formed between the opposing surfaces of the main rubber elastic body 16 and the diaphragm 30 and supported by the second mounting member 14. That is, before attaching the diaphragm 30 to the second mounting bracket 14, the partition member 40 is inserted into the second mounting bracket 14 from the lower opening of the second mounting bracket 14. Thereafter, the diaphragm 30 is inserted into the second mounting member 14 from the lower opening, and the diaphragm 30 is overlapped with the partition member 40 from below. And, in such a state that the partition member 40 and the diaphragm 30 are inserted into the second mounting bracket 14 as described above, the partition member 40 The diaphragm 30 can be simultaneously fixed to the second mounting bracket 14.

  In this way, the partition member 40 is disposed so as to expand in the direction perpendicular to the axis in the fluid sealing region 38, so that the fluid sealing region 38 is divided into two vertically. That is, on the upper side in the axial direction across the partition member 40, a part of the wall portion is constituted by the main rubber elastic body 16, and pressure fluctuation based on elastic deformation of the main rubber elastic body 16 is caused when a vibration load is input. A pressure receiving chamber 60 is formed. On the other hand, on the lower side in the axial direction across the partition member 40, an equilibrium chamber 62 in which a part of the wall portion is constituted by the diaphragm 30 and volume change is easily allowed is formed. The pressure receiving chamber 60 and the equilibrium chamber 62 are filled with incompressible fluid sealed in the fluid sealing region 38, respectively.

  Further, the outer peripheral surface of the partition member 40 is brought into close contact with the inner peripheral surface of the second mounting member 14 via the seal rubber layer 28, so that the outer peripheral side opening of the peripheral groove 52 formed in the partition member 40 is formed. The second mounting bracket 14 is closed. One end portion in the length direction of the circumferential groove 52 is communicated with the pressure receiving chamber 60 through the communication hole 64, and the other end portion in the length direction of the circumferential groove 52 is communicated with the equilibrium chamber 62 through the communication hole 66. I'm hurt. As a result, a first orifice passage 68 as a low frequency orifice passage communicating the pressure receiving chamber 60 and the equilibrium chamber 62 with each other is formed using the circumferential groove 52.

  The first orifice passage 68 in the present embodiment has a low frequency region around 10 Hz corresponding to an engine shake that tends to cause a problem in the running state of the automobile by adjusting the ratio of the length and the cross-sectional area of the passage. The vibration is tuned so as to exhibit an anti-vibration effect based on the resonance action of the fluid.

  Further, the communication recess 48 formed in the partition member 40 is opened toward the equilibrium chamber 62, so that the communication hole 64, a part of the circumferential groove 52, the communication path 54, and the communication recess 48 are cooperated. Due to the action, a second orifice passage 70 is formed as an intermediate frequency orifice passage that allows the pressure receiving chamber 60 and the equilibrium chamber 62 to communicate with each other. The second orifice passage 70 is tuned so as to exhibit a vibration isolation effect due to fluid flow against vibrations in a higher frequency range than the first orifice passage 68. In this embodiment, the second orifice passage 70 is The second orifice passage 70 is tuned so that the vibration-proofing effect of the second orifice passage 70 can be exerted against vibrations in the middle frequency range of about a dozen Hz corresponding to the idling vibration that is likely to cause a problem in a stopped state.

  A negative pressure actuator 72 is disposed below the mount body 11 having such a structure. The negative pressure actuator 72 includes a base bracket 74 and a movable partition member 76.

  The base bracket 74 is a highly rigid member having a large-diameter, generally cylindrical shape, and is formed of a metal material such as steel in the present embodiment. An annular mounting leg 78 is superimposed on the outer peripheral surface of the lower end of the base bracket 74 and fixed by means such as welding. The mounting leg 78 is integrally provided with a cylindrical portion 80 that is cylindrical and is fitted and fixed to the base bracket 74, and a mounting flange 82 that extends to the outer peripheral side at the lower end of the cylindrical portion 80. Then, a fixing bolt (not shown) is inserted into bolt holes 84 penetratingly formed at a plurality of locations on the circumference of the mounting flange 82, and the fixing bolt is screwed to the vehicle body, whereby the base A bracket 74 is fixed to the vehicle body.

  A movable partition member 76 is assembled to the base bracket 74. The movable partition member 76 has a partition rubber portion 86 as shown in FIG. The partition rubber portion 86 is formed of a rubber elastic body having a substantially annular plate shape, and an annular fitting 88 is overlapped and vulcanized and bonded to the outer peripheral surface. In the present embodiment, the partition rubber portion 86 is tapered so as to incline upward toward the inner peripheral side, so that a stroke of a reciprocating operation described later can be advantageously ensured.

  Further, an output fitting 90 is vulcanized and bonded to the inner peripheral edge of the partition rubber portion 86. The output metal fitting 90 has a substantially cup shape in the reverse direction, and the opening peripheral edge of the lower side thereof is fixed to the inner peripheral edge of the partition rubber portion 86. Further, a covering rubber layer 92 integrally formed with the partition rubber portion 86 is fixed to the surface of the output fitting 90, and the surface of the output fitting 90 is covered with the covering rubber layer 92 throughout. Furthermore, a circular block-shaped guide rubber 94 protruding downward is integrally formed with the covering rubber layer 92 on the upper bottom wall portion of the output fitting 90. In the present embodiment, the peripheral edge of the opening of the output metal fitting 90 is formed in a flange shape, and an annular stopper rubber 95 protruding downward is integrated with the covering rubber layer 92 on the lower surface of the flange-shaped portion. Is formed.

  The movable partition member 76 structured as described above is fitted to the base bracket 74. That is, the fitting member 88 vulcanized and bonded to the outer peripheral surface of the partition rubber portion 86 in the movable partition member 76 is fitted and fixed to the lower end portion of the base bracket 74, so that the movable partition member 76 is fixed to the base bracket. It superimposes so that it may be located upwards with respect to the bottom wall part of 74. FIG. In the assembled state of the base bracket 74 and the movable partition wall member 76, the output metal fitting 90 is relative to the bottom wall portion of the base bracket 74 in the approach direction and the separation direction in the axial direction due to elastic deformation of the partition wall rubber portion 86. Displaceable.

  In the assembled state of the movable partition member 76 with respect to the base bracket 74, a first working air chamber 96 is formed between the overlapping surfaces of the base bracket 74 and the movable partition member 76. In the first working air chamber 96, a part of the wall portion is formed by a movable partition member 76, and is sealed from the outside.

  The first working air chamber 96 is provided with a coil spring 98 as urging means. The coil spring 98 is inserted into the inner peripheral side of the output fitting 90, and one end in the axial direction is brought into contact with the output fitting 90 via the covering rubber layer 92, and the other in the axial direction. The end portion is brought into contact with the bottom wall portion of the base bracket 74. As a result, an urging force in a direction away from the base bracket 74 is always applied to the output fitting 90 using the elastic force of the coil spring 98. In this embodiment, the guide rubber 94 vulcanized and bonded to the output fitting 90 is inserted into one end of the coil spring 98 with a predetermined gap in the radial direction. Can be stably and easily realized.

  A small-diameter cylindrical port fitting 100 is inserted into the bottom wall portion of the base bracket 74 constituting a part of the wall portion of the first working air chamber 96, and one end of the port fitting 100 is inserted. Is located in the first working air chamber 96, and the other end of the port fitting 100 is connected to the first air duct 102. Further, a first switching valve 104 as a first air pressure switching means is disposed on the first air pipe 102. The first switching valve 104 in the present embodiment is a general three-way valve, and the first working air chamber 96 is connected to the negative pressure source 108 and the atmosphere by the switching operation of the first switching valve 104. It can be communicated alternatively.

  Then, by operating the first switching valve 104, the pressure in the first working air chamber 96 is switched between the atmospheric pressure and the negative pressure, so that the output fitting 90 is driven and displaced in the axial direction. That is, when atmospheric pressure is applied to the first working air chamber 96, the output fitting 90 is displaced upward in the axial direction by the urging force of the coil spring 98 and is held at the top dead center. On the other hand, when a negative pressure is applied to the first working air chamber 96, the output fitting 90 is suctioned and displaced downward in the axial direction against the urging force of the coil spring 98 so as to be held at the bottom dead center. It has become. In this embodiment, the downward displacement of the output fitting 90 is limited in a buffering manner by the contact of the stopper rubber 95 with the base bracket 74.

  The negative pressure actuator 72 having such a structure is assembled to the mount body 11. That is, the second mounting bracket 14 of the mount body 11 is press-fitted and fixed to the base bracket 74 of the negative pressure actuator 72 from above, so that the mount body 11 is assembled to the base bracket 74. An engine mount 10 according to the present embodiment is configured. Note that the upper end portion of the base bracket 74 is brought into contact with the contact flange portion 24, whereby the mount body 11 and the negative pressure actuator 72 are positioned in the axial direction.

  In addition, when the mount body 11 and the negative pressure actuator 72 are assembled, the central portion in the radial direction of the movable partition member 76 is overlapped with the central valve portion 32 of the diaphragm 30 from below in the axial direction. Then, by causing atmospheric pressure to act on the first working air chamber 96, the central valve portion 32 can be brought close to the partition member 40 by the biasing force of the coil spring 98, and top dead center. The second orifice passage 70 is pressed so as to cover the opening of the second orifice passage 70 on the equilibrium chamber 62 side, so that the second orifice passage 70 is blocked. On the other hand, a negative pressure is applied to the first working air chamber 96, and the output fitting 90 is sucked and displaced downward, whereby the central valve portion 32 is separated from the partition member 40, and the second The orifice passage 70 is switched to the communication state.

  Here, the partition member 40 is provided with a movable member 110 as a pressure fluctuation absorbing wall portion. As shown in FIG. 1, the movable member 110 has a structure in which an annular metal fitting 114 and a reinforcing metal fitting 116 are fixed to a plate-like rubber elastic body 112.

  The plate-like rubber elastic body 112 is formed of a rubber elastic body having a substantially disk shape as a whole, and the central portion is a stepped disk-shaped central movable plate portion 118 having a substantially constant thickness. . As will be described later, a reinforcing metal fitting 116 is vulcanized and bonded to the central movable plate portion 118 to form a hard portion that is substantially prevented from elastic deformation.

  Further, on the outer peripheral side of the central movable plate portion 118 in the plate-like rubber elastic body 112, an elastic contact ridge 120 protruding toward both sides in the thickness direction is integrally formed, and the elastic contact ridge 120 is Elastic support protrusions 122 that protrude larger than the elastic contact protrusions 120 toward both sides in the thickness direction are integrally formed at a plurality of locations on the circumference.

  Further, a ring-shaped annular fixing portion 124 is integrally formed on the outer peripheral edge portion of the plate-like rubber elastic body 112. Furthermore, an outer peripheral rubber film portion 126 is integrally formed between the elastic contact protrusion 120 and the elastic support protrusion 122 and the annular fixing portion 124 in the radial direction of the plate rubber elastic body 112. The outer peripheral rubber film portion 126 is a rubber film that is thinner than the central movable plate portion 118 and can be deformed relatively easily, and spreads in a direction perpendicular to the axis at the axial center portion of the annular fixing portion 124. ing.

  An annular metal fitting 114 is vulcanized and bonded to the outer peripheral edge of the plate-like rubber elastic body 112 having such a structure. The annular metal fitting 114 has an annular shape corresponding to the circular recess 46 formed in the partition member main body 42, and in this embodiment, the metal has a rigidity that does not cause a problem of deformation due to the action of pressure input. It is made of material.

  In addition, a reinforcing metal fitting 116 is embedded and fixed to the central movable plate portion 118 of the plate-like rubber elastic body 112, and the central movable plate portion 118, which is the central portion of the movable member 110, is reinforced by the reinforcing metal fitting 116 and substantially. It is considered to be hard. The reinforcing metal fitting 116 has a thin and substantially disk shape, and as shown by a broken line in FIG. 6, notches are formed at a plurality of locations corresponding to the elastic support protrusions 122 on the circumference. . Further, a circular through hole is formed in the central portion in the radial direction of the reinforcing metal fitting 116, and minute deformation of the plate-like rubber elastic body 112 is allowed at the position where the through hole is formed.

  The movable member 110 having such a structure is fitted into a circular recess 46 formed in the partition member main body 42 and assembled between the opposing surfaces of the partition member main body 42 and the lid fitting 44. That is, the annular metal fitting 114 vulcanized and bonded to the outer peripheral surface of the plate-like rubber elastic body 112 is press-fitted into the circular recess 46 and fixed, and the elastic support protrusion 122 is opposed to the partition member main body 42 and the cover metal fitting 44. It is sandwiched between the surfaces and is elastically supported.

  Under such an assembly, the movable member 110 is supported by the central movable plate portion 118 so as to be slightly displaceable based on the elastic deformation of the elastic support protrusion 122, and the outer peripheral rubber film portion 126 has the partition member main body 42 and the lid. It is separated from any of the metal fittings 44 and is allowed to be minutely deformed. Note that a minute gap is provided between the protruding tip of the elastic contact protrusion 120 and the partition member main body 42 and the cover metal 44, and the partition member main body 42 and the cover metal 44 44 due to displacement or deformation of the movable member 110. It can come into contact with either one of these.

  In addition, a sub liquid chamber 128 is formed between the movable member 110 and the lid fitting 44 under the arrangement of the movable member 110. A part of the wall portion of the sub liquid chamber 128 is configured by the movable member 110 and an incompressible fluid similar to that of the pressure receiving chamber 60 and the equilibrium chamber 62 is enclosed.

  In addition, a circular through hole is formed at a central portion in the radial direction of the lid fitting 44, and a central cylindrical portion 130 that protrudes upward from the opening peripheral edge of the through hole is integrally formed. As a result, a third orifice passage 132 as a high-frequency orifice passage communicating the pressure receiving chamber 60 and the sub liquid chamber 128 with each other is formed using the central hole of the central cylindrical portion 130. The third orifice passage 132 is tuned so as to obtain a desired vibration-proofing effect against vibrations in a higher frequency range than the second orifice passage 70. In this embodiment, the third orifice passage 132 is an automobile. It is set so as to exhibit an anti-vibration effect against high-frequency vibrations of around 70 Hz, which corresponds to a running-over sound that is likely to cause problems during high-speed running.

  Further, the pressure fluctuation of the pressure receiving chamber 60 transmitted to the sub liquid chamber 128 through the third orifice passage 132 is exerted on one surface of the central movable plate portion 118 in the movable member 110.

  Further, in the lid fitting 44, a plurality of through holes 134 extending in the circumferential direction with a predetermined length are formed at positions corresponding to the outer peripheral rubber film portion 126 of the movable member 110. As a result, the pressure of the sub liquid chamber 128 communicated with the pressure receiving chamber 60 through the through hole 134 is applied to one surface of the outer peripheral rubber film portion 126.

  Further, the central movable plate portion 118 that is the central portion in the radial direction of the movable member 110 is positioned so as to cover the opening of the central recess 50 formed in the partition member main body 42. Thus, a second working air chamber 136 separated from the outside is formed on the opposite side (lower side in FIG. 1) from the pressure receiving chamber 60 with the movable member 110 interposed therebetween.

  Furthermore, an annular annular recess 138 is formed in a portion of the partition member main body 42 corresponding to the outer peripheral rubber film portion 126 of the movable member 110, and is opened upward in the axial direction. Furthermore, between the radial direction of the annular recess 138 and the central recess 50, a communication concave groove 140 extending in the radial direction is formed at a plurality of locations on the circumference, and the central recess 50 and the annular recess are formed through the communication concave groove 140. Recesses 138 are in communication with each other. As a result, the pressure of the second working air chamber 136 is applied to the annular recess 138 through the communication recess groove 140, and the second working air chamber 136, the annular recess 138, and the communication recess groove 140 are applied. Thus, the second working air chamber in this embodiment is formed.

  In addition, a port portion 142 is integrally formed on the outer peripheral edge of the partition member main body 42 at a part of the periphery. One end of the central hole of the port 142 is communicated with the second working air chamber 136. Further, the other end of the port portion 142 is exposed to the outside through an insertion hole penetrating the second mounting bracket 14, the seal rubber layer 28, and the base bracket 74, and is inserted through the insertion hole. Are connected to the air pipe 144. Furthermore, a second switching valve 146 serving as a second air pressure switching unit is disposed on the second air pipe 144. In the present embodiment, the second switching valve 146 is configured by a general three-way valve as with the first switching valve 104, and the second working air chamber 136 is operated to switch the second switching valve 146. Thus, the negative pressure source 148 and the atmosphere can be selectively communicated with each other.

  Then, the second switching valve 146 is switched and the pressure exerted on the second working air chamber 136 is switched, whereby the movable member 110 is switched between the suction restraint state and the deformation-permitted state. ing. That is, when a negative pressure is applied to the second working air chamber 136, the negative pressure is applied to the lower surface of the movable member 110, and the movable member 110 is sucked toward the second working air chamber 136 to move. The member 110 is in a restrained state in which the deformation or displacement of the member 110 is limited. On the other hand, when atmospheric pressure is applied to the second working air chamber 136, the atmospheric pressure is applied to the lower surface of the movable member 110, and the movable member 110 is allowed to be deformed or displaced so that the restraint is released. .

  The first switching valve 104 that switches the pressure exerted on the first working air chamber 96 and the second switching valve 146 that switches the pressure exerted on the second working air chamber 136 are controlled as switching control means. The operation is controlled by the device 150. The control device 150 can independently control the first switching valve 104 and the second switching valve 146, and can switch the switching valves 104 and 146 at any timing independent of each other. I can do it.

  In a state where the engine mount 10 having such a structure is mounted on a vehicle, when vibration in a low frequency range corresponding to an engine shake is input, the first difference is based on the pressure difference between the pressure receiving chamber 60 and the equilibrium chamber 62. A fluid is caused to flow between the two chambers 60 and 62 through the orifice passage 68 so that a vibration isolation effect based on a fluid action such as a resonance action of the fluid is exhibited.

  Further, when a vibration in the middle frequency range corresponding to the idling vibration is input in a state in which the engine mount 10 is mounted on the vehicle, the second mount passage 70 passes through the second orifice passage 70 based on the pressure difference between the pressure receiving chamber 60 and the equilibrium chamber 62. A fluid is caused to flow between the two chambers 60 and 62 so that an anti-vibration effect based on a fluid action such as a resonance action of the fluid is exhibited.

  Further, when vibration in a high frequency range corresponding to traveling noise is input in a state where the engine mount 10 is mounted on the vehicle, the third orifice passage 132 is based on the pressure difference between the pressure receiving chamber 60 and the sub liquid chamber 128. Thus, the fluid is caused to flow between the two chambers 60 and 128 so that a vibration isolation effect based on a fluid action such as a resonance action of the fluid is exhibited.

  Here, in the engine mount 10 according to the present embodiment, the first switching valve 104 and the second switching valve 146 are switched independently of each other by the control device 150, so that the first working air chamber 96 is controlled. The pressure and the pressure in the second working air chamber 136 can be switched separately. Accordingly, it is possible to effectively obtain the vibration isolation effect exhibited by the orifice passages 68, 70, and 132, and to input vibrations in a frequency range higher than the tuning frequencies of the second and third orifice passages 70 and 132. By virtue of the anti-resonant action of the second and third orifice passages 70 and 132, it is possible to prevent the vibration-proof performance from deteriorating.

  Below, the operation control method of the engine mount 10 in this embodiment is demonstrated.

  More specifically, at the time of vibration input in the low frequency range (around 10 Hz) corresponding to the engine shake, as shown in FIG. 7, the first switching valve 104 is switched by the control device 150, and the first switching valve 104 is switched. One working air chamber 96 is communicated with the atmosphere. As a result, the central valve portion 32 of the diaphragm 30 is pressed against the opening of the second orifice passage 70 on the equilibrium chamber 62 side, and the second orifice passage 70 is blocked. Therefore, the pressure fluctuation induced in the pressure receiving chamber 60 through the second orifice passage 70 can be prevented from being released to the equilibrium chamber 62.

  Further, when a vibration corresponding to the engine shake is input, the second switching valve 146 is switched by the control device 150 and the second working air chamber 136 is communicated with the negative pressure source 148. Thereby, a negative pressure is exerted on the second working air chamber 136, and the movable member 110 constituting a part of the wall portion of the sub liquid chamber 128 is sucked and restrained to the second working air chamber 136 side. . Therefore, the third orifice passage 132 is substantially blocked, and the pressure fluctuation of the pressure receiving chamber 60 can be prevented from being released to the sub liquid chamber 128 through the third orifice passage 132.

  As a result, it is possible to secure a large amount of fluid flow between the pressure receiving chamber 60 and the equilibrium chamber 62 through the first orifice passage 68 by efficiently causing the pressure fluctuation in the pressure receiving chamber 60. The anti-vibration effect exhibited based on the fluid flow through the first orifice passage 68 can be effectively obtained.

  In addition, when the vibration is input in the middle frequency range (about several tens of Hz) corresponding to the idling vibration, the first switching valve 104 is switched by the control device 150 as shown in FIG. The negative pressure of the negative pressure source 108 is exerted on the first working air chamber 96. As a result, the diaphragm 30 is separated from the opening of the second orifice passage 70 on the side of the equilibrium chamber 62, and the second orifice passage 70 tuned to the middle frequency range is communicated. The fluid flow through the second orifice passage 70 is generated based on the relative pressure fluctuation between the pressure receiving chamber 60 and the equilibrium chamber 62.

  Further, when vibration corresponding to idling vibration is input, the second switching valve 146 is switched by the control device 150, and the second working air chamber 136 is communicated with the negative pressure source 148. Thus, when negative pressure is applied to the second working air chamber 136, the movable member 110 constituting a part of the wall portion of the sub liquid chamber 128 is sucked toward the second working air chamber 136. Be bound. Thereby, the relative pressure fluctuation of the pressure receiving chamber 60 and the sub liquid chamber 128 is prevented, and the third orifice passage 132 is substantially blocked. Therefore, it is possible to prevent the pressure fluctuation in the pressure receiving chamber 60 from being released to the sub liquid chamber 128 through the third orifice passage 132.

  At the time of vibration input in the middle to high frequency range, the first orifice passage 68 is substantially blocked by the antiresonant action, and fluid flow through the first orifice passage 68 is prevented. ing.

  As a result, the pressure fluctuation induced in the pressure receiving chamber 60 is prevented from escaping through the first and third orifice passages 68 and 132, and the pressure receiving chamber 60 and the equilibrium chamber 62 formed by the second orifice passage 70 are prevented. The fluid flow between them can be generated efficiently. Accordingly, it is possible to more effectively obtain the vibration isolation effect that is exhibited based on the fluid flow through the second orifice passage 70.

  In addition, vibration in a frequency range higher than the tuning frequency of the second orifice passage 70 and in a lower frequency range than the tuning frequency of the third orifice passage 132, more specifically, vibration of about 50 Hz to 70 Hz is input. In this case, both the first and second orifice passages 68 and 70 are substantially cut off by antiresonant action, and the dynamic spring constant of the engine mount 10 tends to increase.

  Therefore, in the engine mount 10 according to the present embodiment, as shown in FIG. 7, the first switching valve 104 is controlled by the control device 150 to be switched when a vibration of about 50 Hz to 70 Hz is input. As a result, the first working air chamber 96 is communicated with the negative pressure source 108. Thereby, a negative pressure is exerted on the first working air chamber 96, and the second orifice passage 70 is brought into a communication state.

  Further, the second switching valve 146 is controlled by the control device 150 to be switched, whereby the second working air chamber 136 is communicated with the atmosphere. When the atmospheric pressure is applied to the second working air chamber 136, the restraint due to the negative pressure of the movable member 110 is released, and the displacement or deformation of the movable member 110 is allowed.

  Then, the central movable plate portion 118 of the movable member 110 is slightly displaced based on the hydraulic pressure of the sub liquid chamber 128 exerted on one surface of the movable member 110, and the outer peripheral rubber film portion 126 is elastically deformed. The pressure fluctuation exerted on the pressure receiving chamber 60 is absorbed, and the fluid flow through the second orifice passage 70 is suppressed. As a result, an increase in the dynamic spring constant of the engine mount 10 due to the anti-resonant action of the fluid flowing through the second orifice passage 70 can be suppressed. It is possible to effectively reduce the decrease.

  Further, as shown in FIG. 7, when the vibration is input in a high frequency range (about 70 Hz to 100 Hz) corresponding to the traveling noise, the first switching valve 104 is switched by the control device 150. An atmospheric pressure is exerted on the first working air chamber 96. As a result, the second orifice passage 70 is blocked, and the internal pressure of the pressure receiving chamber 60 can be prevented from escaping to the equilibrium chamber 62 through the second orifice passage 70.

  Further, the second switching valve 146 is switched by the control device 150, and atmospheric pressure is exerted on the second working air chamber 136. As a result, the movable member 110 is brought into a restrained release state in which deformation or displacement is allowed, and volume change of the sub liquid chamber 128 based on elastic deformation or displacement of the movable member 110 is allowed. Based on the relative pressure difference generated between the pressure receiving chamber 60 and the sub liquid chamber 128, fluid flow is generated between the pressure receiving chamber 60 and the sub liquid chamber 128 through the third orifice passage 132. Thus, an anti-vibration effect based on the fluid flow action is exhibited.

  Moreover, in the present embodiment, the outer peripheral rubber film portion 126 provided on the outer peripheral portion of the movable member 110 is slightly deformed, thereby exhibiting a hydraulic pressure absorbing action that absorbs pressure fluctuations exerted on the pressure receiving chamber 60. It is possible to obtain a vibration isolation effect more effectively.

  Further, when vibration in a frequency range higher than the tuning frequency of the third orifice passage 132 (hundreds of tens Hz) is input, the anti-resonant action of the third orifice passage 132 causes the movement of the engine mount 10. The spring constant tends to increase.

  Therefore, in the engine mount 10 according to the present embodiment, as shown in FIG. 7, the first switching valve 104 is controlled by the control device 150 when the vibration is input in the frequency range of several hundreds of Hz. By being actuated, the first working air chamber 96 is brought into communication with the atmosphere. As a result, atmospheric pressure is applied to the first working air chamber 96, and the second orifice passage 70 is shut off. Therefore, it is possible to prevent the dynamic spring characteristics from being deteriorated due to the antiresonance of the fluid flowing through the second orifice passage 70.

  Further, at the time of vibration input in the frequency range of hundreds of tens Hz, the second switching valve 146 is controlled by the control device 150 to be switched, so that the second working air chamber 136 communicates with the negative pressure source 148. It is done. Then, a negative pressure is applied to the second working air chamber 136, and a restraining force due to the negative pressure is applied to the movable member 110. Accordingly, the displacement or deformation of the movable member 110 is limited, and fluid flow through the third orifice passage 132 is prevented. Therefore, the increase in the dynamic spring constant of the engine mount 10 due to the anti-resonant action of the fluid flowing through the third orifice passage 132 is effectively prevented, and the deterioration of the vibration isolation performance is prevented. I can do it.

  Thus, it is apparent from the measurement results shown in FIGS. 8 and 9 that the anti-vibration performance effective in a wider frequency range can be effectively exhibited in the engine mount 10 according to the present embodiment.

  That is, as shown in FIG. 8, when the low frequency vibration around 10 Hz corresponding to the engine shake is input, the engine mount 10 according to the present embodiment indicated by the solid line is employed. In the embodiment, the high damping effect based on the fluid flow through the first orifice passage 68 is more advantageous than the comparative example in which the characteristic switching type engine mount having the conventional structure shown by the broken line is adopted. It has been demonstrated that it is possible to obtain a more effective anti-vibration effect against low-frequency large-amplitude vibration.

  Furthermore, as shown in FIG. 9, the dynamic spring constant of the example is suppressed to be smaller than the dynamic spring constant of the comparative example at the time of vibration input in the middle to high frequency range. In particular, the high dynamic spring due to the anti-resonant action of the second orifice passage 70 is problematic, and the high dynamic spring due to the anti-resonant action of the third orifice passage 132 is problematic. It is shown in the measurement results of FIG. 9 that the dynamic spring constant can be reduced very effectively when a vibration input of several tens of Hz is applied.

  Note that in a state where the engine mount 10 is mounted on a vehicle, generally, vibrations in a plurality of different frequency ranges are input in a composite manner. Since it varies depending on the number of rotations (accelerator opening), etc., it responds to input vibration by controlling the first and second switching valves 104, 146 with the control device 150 according to changes in the running state, etc. The switching state to be realized can be realized, and an effective anti-vibration effect can be obtained.

  Next, FIG. 10 shows an engine mount 152 for an automobile as a second embodiment of the fluid filled type vibration damping device according to the present invention. In addition, in the following description, about the member thru | or site | part substantially the same as said 1st embodiment, description is abbreviate | omitted by attaching | subjecting the same code | symbol in a figure.

  That is, the engine mount 152 has a partition member 154. The partition member 154 has a thick, substantially disk shape, similar to the partition member 40 shown in the first embodiment, and includes the partition member main body 42, the lid fitting 156, and the movable member 110. Has been.

  As shown in FIGS. 10 and 11, the lid fitting 156 is formed of a thin metal plate having a substantially disk shape as a whole. In addition, the lid fitting 156 has a central through hole 158 formed in a circular hole shape in the central portion in the radial direction, and an outer peripheral through hole 160 formed in the middle portion in the radial direction. As shown in FIG. 11, the outer peripheral through hole 160 is a through hole extending in a predetermined length in the circumferential direction, and a plurality of outer peripheral through holes 160 are spaced apart from each other by a predetermined distance on the same circumference. Is formed.

  Further, a cylindrical inner peripheral wall portion 162 is formed on the inner peripheral side and a cylindrical outer peripheral wall portion 164 is formed on the outer peripheral side at the opening peripheral portion of the outer peripheral through hole 160 in the lid fitting 156. . Both the inner peripheral wall portion 162 and the outer peripheral wall portion 164 are integrally formed with the lid fitting 156, protruded upward in the axial direction at a predetermined height, and both sides sandwiching the outer peripheral through hole 160 in the radial direction. These inner peripheral wall 162 and outer peripheral wall 164 are formed.

  The lid fitting 156 having such a structure is overlapped and fixed from above in the axial direction to the partition member main body 42 to which the movable member 110 is assembled. Under the assembly to the partition member main body 42, the central through hole 158 is formed at a position corresponding to the central movable plate portion 118 of the movable member 110, and the outer peripheral through hole 160 is the outer peripheral rubber film portion of the movable member 110. It is formed at a position corresponding to 126.

  The partition member 154 provided with the lid fitting 156 having such a structure is supported by the second mounting fitting 14 and accommodated in the fluid sealing region 38 as in the first embodiment. Accordingly, as in the first embodiment, the pressure receiving chamber 60 and the equilibrium chamber 62 are formed on both sides of the partition member 154 on the inner peripheral side of the second mounting bracket 14.

  Further, under the housing arrangement of the partition member 154 in the fluid sealing region 38, the pressure receiving chamber 60 and the auxiliary liquid chamber 128 are connected to each other as a high-frequency orifice passage by the cooperation of the outer peripheral through hole 160 and the inner and outer peripheral wall portions 162 and 164. A third orifice passage 166 is formed. The third orifice passage 166 is tuned to a high frequency range corresponding to a traveling boom noise, similarly to the third orifice passage 132 shown in the first embodiment.

  Furthermore, under the accommodation arrangement in the fluid sealing region 38, the pressure receiving chamber 60 and the secondary liquid chamber 128 are communicated with each other through the central through hole 158, and the filter orifice in the present embodiment is utilized by using the central through hole 158. Is formed. The filter orifice is tuned to a frequency higher than the tuning frequency of the third orifice passage 166.

  Here, even in a state where the engine mount 152 according to the present embodiment is mounted on an automobile, low frequency range vibration corresponding to engine shake and middle frequency range corresponding to idling vibration are controlled by the same control as in the above embodiment. And vibrations in a high frequency range corresponding to traveling noise are effectively exerted on the basis of the fluid flow action, and the orifice passages 68, 70, 166 A significant increase in the dynamic spring constant due to the anti-resonant action can be prevented, and deterioration of the vibration isolation characteristics can be reduced.

  In addition, when vibration in a higher frequency region becomes a problem than the frequency region in which the anti-resonance of the third orifice passage 166 becomes a problem, the first switching valve 104 is controlled by the control device 150. Atmospheric pressure is applied to the first working air chamber 96, and the second switching valve 146 is controlled by the control device 150, whereby atmospheric pressure is applied to the second working air chamber 136. It is like that.

  As a result, the pressure fluctuation induced in the pressure receiving chamber 60 based on the vibration input is exerted on the central movable plate portion 118 of the movable member 110 through the central through hole 158 formed in the central portion of the lid fitting 156, so that the central movable member is movable. The plate portion 118 can be slightly displaced, and a vibration isolation effect based on the hydraulic pressure absorbing action is exhibited.

  Although several embodiments of the present invention have been described above, these are merely examples, and the present invention is not construed as being limited to specific descriptions in such embodiments.

  For example, the operation control by the control device 150 shown in the first and second embodiments is merely an example, and the input vibration in question, the desired vibration-proof performance, the durability of the device, and the reliability of the control. It can be appropriately controlled in consideration of the properties and the like. That is, for example, it is possible to selectively combine the controls corresponding to the vibrations that are problematic from the mode of the switching control shown in the embodiment. Specifically, when the deterioration of the dynamic spring characteristics due to anti-resonance of the high-frequency orifice passage is not a problem, it is necessary to switch the vibration-proof characteristic against vibration at a frequency that causes anti-resonance of the high-frequency orifice passage. Absent.

  Furthermore, the specific numerical values of the frequencies in the control methods shown in the first and second embodiments are merely examples, and are not particularly limited. It is set appropriately according to the characteristics.

  In the first and second embodiments, the first and second switching valves 104 and 146 are independently controlled by one control device 150. For example, each switching valve is controlled separately. An apparatus may be provided to control the switching valve independently. Furthermore, in the first and second embodiments, the first and second working air chambers 96 and 136 are connected to different negative pressure sources 108 and 150 through the first and second air pipes 102 and 144, respectively. However, it may be connected to the same negative pressure source.

  In the first and second embodiments, examples in which the fluid-filled vibration isolator according to the present invention is employed as an engine mount are shown, but the present invention is not necessarily applied only to the engine mount. However, the present invention can be applied to various fluid-filled vibration isolators such as suspension member mounts and body mounts.

  Furthermore, in the first and second embodiments, examples in which the present invention is applied to an engine mount of an automobile are shown. However, the scope of application of the present invention is limited to a fluid-filled vibration isolator for an automobile. For example, a fluid-filled vibration isolator for trains and a fluid-filled vibration isolator used for various other purposes can be within the scope of the present invention.

  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.

II sectional drawing of FIG. 2 which shows the engine mount as 1st embodiment of this invention. The top view of the partition member which comprises the same engine mount. The bottom view of the partition member which comprises the same engine mount. The perspective view of the partition member main body which comprises the partition member. The top view of the cover metal fitting which comprises the partition member. The top view of the movable member which comprises the partition member. Explanatory drawing which shows the operation control method of the engine mount. The graph which shows the attenuation in the low frequency region of the engine mount. The graph which shows the dynamic spring constant of the engine mount. Sectional drawing which shows the engine mount as 2nd embodiment of this invention. The top view of the cover metal fitting which comprises the engine mount.

Explanation of symbols

10: engine mount, 12: first mounting bracket, 14: second mounting bracket, 16: rubber elastic body, 30: diaphragm, 32: central valve, 60: pressure receiving chamber, 62: equilibrium chamber, 68: First orifice passage, 70: Second orifice passage, 72: Negative pressure actuator, 96: First working air chamber, 98: Coil spring, 104: First switching valve, 108: Negative pressure source, 110: Movable member, 118: central movable plate portion, 126: outer peripheral rubber film portion, 128: secondary liquid chamber, 132, 166: third orifice passage, 136: second working air chamber, 146: second switching valve, 148: negative pressure source, 150: control device, 158: central through hole, 160: outer peripheral through hole

Claims (6)

The first mounting member and the cylindrical second mounting member are spaced apart from each other, and the first mounting member and the second mounting member are elastically connected to each other by a main rubber elastic body. A pressure receiving chamber in which a part of the wall is made of the main rubber elastic body on both sides of the partition member supported by the second mounting member, and a part of the wall is made of a flexible film. The fluid-filled vibration isolating apparatus in which an incompressible fluid is sealed in the pressure receiving chamber and the equilibrium chamber, and an orifice passage is formed to communicate the pressure receiving chamber and the balance chamber with each other. In
The orifice passage is tuned at a higher frequency than the low-frequency orifice passage by communicating the pressure-receiving chamber and the equilibrium chamber with each other, and a low-frequency orifice passage communicating with the pressure-receiving chamber and the equilibrium chamber. A frequency orifice passage, and the valve body is pressed against the opening of the medium frequency orifice passage to the equilibrium chamber by an urging means so that the medium frequency orifice passage is blocked. And a first working air chamber is provided to apply a negative pressure to the first working air chamber, thereby causing the valve body to resist the biasing force of the biasing means. A negative pressure actuator is provided to communicate the medium frequency orifice passage away from the opening of the orifice passage to the equilibrium chamber, and the first working air chamber of the negative pressure actuator is a first air. By selectively maintaining the negative pressure source and the atmosphere in communication with the switching means, the valve body is driven to switch the medium frequency orifice passage between the communication state and the cutoff state. A sub liquid chamber in which a part of the wall portion is constituted by a pressure fluctuation absorbing wall portion and in which an incompressible fluid is sealed is formed, and the intermediate pressure is communicated with the pressure receiving chamber and the sub liquid chamber. A high-frequency orifice passage tuned to a frequency higher than that of the orifice passage is formed, and a second working air chamber formed on the opposite side of the subfluid chamber with the pressure fluctuation absorbing wall portion interposed therebetween is a first working air chamber. The pressure fluctuation absorbing wall portion can be switched between a suction restraint state due to negative pressure and a deformation-permitted state by being selectively held in communication with the negative pressure source and the atmosphere by the second air pressure switching means. The first air Independently of each other with is adapted to be switched controlled by switching means and said second air pressure switching means switching control means,
In a mode in which the switching control means connects and holds the first working air chamber of the negative pressure type actuator in the atmosphere under vibration input conditions in a frequency range higher than the resonance frequency of the high frequency orifice passage. A fluid-filled type vibration damping device , wherein the air pressure switching means is operated, and the second air pressure switching means is operated in such a manner that the second working air chamber is connected and held to a negative pressure source .   The low frequency orifice passage is tuned to a frequency corresponding to an automobile engine shake, the medium frequency orifice passage is tuned to a frequency corresponding to automobile idling vibration, and the high frequency orifice passage is The fluid filled type vibration damping device according to claim 1, which is tuned to a frequency corresponding to traveling noise.   The pressure fluctuation absorbing wall portion has a hard central movable plate portion and an outer peripheral movable film portion that is provided on the outer peripheral side of the central movable plate portion and easily allows elastic deformation, and the central movable plate And the outer peripheral movable film part are disposed so as to be allowed to be displaced or deformed, the high-frequency orifice passage is formed at a position corresponding to the outer peripheral movable film part, and the central movable plate part The fluid-filled vibration isolator according to claim 1 or 2, wherein a filter orifice tuned to a frequency region higher than that of the high-frequency orifice passage is formed at a position corresponding to.   In a mode in which the switching control means connects and holds the first working air chamber of the negative pressure actuator to a negative pressure source under vibration input conditions in a frequency range higher than the resonance frequency of the medium frequency orifice passage. 4. The fluid according to claim 1, wherein the first air pressure switching unit is operated and the second air pressure switching unit is operated in such a manner that the second working air chamber is connected and held in the atmosphere. Enclosed vibration isolator. The first air pressure switching means is configured in such a manner that the switching control means keeps the first working air chamber of the negative pressure actuator connected to the atmosphere under vibration input conditions in the resonance frequency region of the low frequency orifice passage. together allowed to operate the fluid-filled vibration damping according to any one of claims 1 to 4 allowed to operate the second air pressure switching means in a manner that the connecting and retaining the second working air chamber to a negative pressure source apparatus. An operation control method for the fluid filled type vibration damping device according to any one of claims 1 to 3,
(I) In a mode in which the switching control means connects and holds the first working air chamber of the negative pressure actuator in the atmosphere under vibration input conditions in a resonance frequency range of the low frequency orifice passage. Actuation control for activating the second air pressure switching means to operate the air pressure switching means and connect and hold the second working air chamber to the negative pressure source;
(Ii) A mode in which the switching control means connects and holds the first working air chamber of the negative pressure actuator to a negative pressure source under a vibration input condition in a frequency range higher than the resonance frequency of the medium frequency orifice passage. Operating the first air pressure switching means and operating the second air pressure switching means in such a manner that the second working air chamber is connected and held in the atmosphere.
(Iii) In a mode in which the switching control means connects and holds the first working air chamber of the negative pressure actuator in the atmosphere under vibration input conditions in a frequency range higher than the resonance frequency of the high-frequency orifice passage. An operation control for activating the second air pressure switching means in such a manner that the first air pressure switching means is operated and the second working air chamber is connected and held to a negative pressure source;
And operation control method for a fluid filled vibration damping device according to claim containing Mukoto.

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