JP2007263301A - Fluid-filled vibration isolator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a fluid-filled vibration isolator capable of positively switching the opening and closing of orifice passages with a stable vibration isolating characteristic, compact in size with superior durability while avoiding an increase in size. <P>SOLUTION: This fluid-filled vibration isolator is provided with a first orifice passage 68 tuned to a low frequency area and a second orifice passage 76 tuned to a high frequency area. The second orifice passage 76 has a control part formed extending in a partitioning member 36, and a valve hole 78 opening to an equilibration chamber 58 is formed in the wall of the control part. A valve element 80 is assembled to the vibration isolator for shutting off the second orifice passage 76 by being inserted into the valve hole 78 while being able to enter and exit the valve hole 78, and a valve element driving means 82 is provided for switching the second orifice passage 76 between a communicated state and a shut-off state by driving and displacing the valve element 80 in the entering/exiting direction with respect to the valve hole 78. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a vibration isolator that is suitably employed for, for example, an automobile engine mount or body mount, and in particular, exhibits a vibration isolating characteristic that is exhibited based on the flow action of an incompressible fluid sealed inside. The present invention relates to a fluid-filled vibration isolator that can be switched according to the situation.

  Conventionally, as a type of vibration isolator that is mounted between members constituting a vibration transmission system, a fluid-filled vibration isolator that obtains a vibration isolating effect by using a fluid action of a fluid sealed inside. It has been known. Such a vibration isolator generally connects a first attachment member attached to one member constituting a vibration transmission system and a second attachment member attached to the other member with a main rubber elastic body, A pressure receiving chamber and an equilibrium chamber are formed on both sides of the partition member supported by the mounting member, and the pressure receiving chamber and the equilibrium chamber are communicated with each other by an orifice passage. Further, when vibration is input, a vibration isolation effect is obtained based on the resonance action of the fluid that is caused to flow through the orifice passage based on the relative pressure fluctuation caused between the pressure receiving chamber and the equilibrium chamber. For example, the one described in Patent Document 1 (Japanese Patent Laid-Open No. 8-270718).

  By the way, in such a fluid-filled vibration isolator, the vibration frequency region in which the vibration isolating effect based on the fluid flow action is effectively exhibited is a limited frequency region in which the orifice passage is tuned. On the other hand, the frequency range in which the anti-vibration effect is required for the anti-vibration device generally covers a plurality of or a wide frequency range. For example, an engine mount for automobiles is required to have an anti-vibration effect against vibrations in a low frequency range such as an engine shake during driving, while being required to have anti-vibration effects against vibrations in a high frequency range such as idling vibration when the vehicle is stopped. It becomes.

  Therefore, in order to effectively exhibit the vibration isolation effect based on the fluid flow action with respect to a plurality of vibrations in a wide frequency range, as shown in Patent Document 1, a low frequency is used. Forming a first orifice passage tuned in the region and a second orifice passage tuned in the high frequency region, and opening and closing the valve body for opening and closing the second orifice passage and the air pressure for opening and closing the valve body A fluid-filled vibration isolator having a structure provided with an actuator of the type has been proposed.

  However, in the conventional fluid-filled vibration isolator described in Patent Document 1, a pneumatic actuator is disposed outside the flexible membrane that defines the equilibrium chamber, and an output member of the actuator is provided. By pressing the flexible membrane against the opening of the second orifice passage, the opening to the equilibrium chamber in the second orifice passage is fluid-tightly closed with the flexible membrane and the second orifice passage is blocked. I was supposed to.

  Therefore, in a state where the opening to the equilibrium chamber of the second orifice passage is covered with a flexible membrane from the equilibrium chamber side and the second orifice passage is blocked, the pressure receiving chamber is passed through the second orifice passage. The applied fluid pressure will be exerted in a direction to push the actuator back through the flexible membrane and open the second orifice passage. Therefore, there are cases where it is difficult to keep the second orifice passage in a shut-off state, and there is also a problem that it is difficult to stably exhibit the target vibration isolation performance.

  In order to cope with such a problem, it is conceivable to set the pressing force of the flexible film by the actuator to be sufficiently large. However, the increase in the size of the actuator and the increase in energy consumption are problematic. In addition, when the pressing force of the actuator is increased, the thin flexible membrane is repeatedly pinched with a large force between the output member and the partition member of the actuator, so that the durability of the flexible membrane is poor. There was also a risk of becoming sufficient.

JP-A-8-270718

  Here, the present invention has been made in the background as described above, and the problem to be solved is a fluid that can stably and reliably switch the vibration-proof characteristic by opening and closing the orifice passage. An enclosed type vibration isolator is to realize a compact and excellent durability while avoiding an increase in size.

  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 mounting member and the second mounting member are connected by the main rubber elastic body, and the partition member is supported by the second mounting member so that the partition member is sandwiched between the first mounting member and the second mounting member. On the other side, a part of the wall portion is formed of the main rubber elastic body to form a pressure receiving chamber into which vibration is input, and the wall portion is formed of a flexible film on the other side of the partition member. Forming a variable volume equilibrium chamber formed of a part of the pressure chamber, enclosing an incompressible fluid in the pressure receiving chamber and the equilibrium chamber, and forming an orifice passage communicating the pressure receiving chamber and the equilibrium chamber with each other. In the fluid-filled vibration isolator that obtains the vibration isolation effect based on the fluid action of the fluid that is allowed to flow through the orifice passage, the orifice passage includes a first orifice passage that is tuned to a low frequency range; Tuned to high frequency range The second orifice passage is formed with a control portion extending inside the partition member, and a valve hole is formed in the wall portion of the control portion to open to the equilibrium chamber. By assembling a valve body that can be inserted into and removed from the hole and that is inserted into the valve hole, the valve body is driven and displaced with respect to the valve hole in the direction of entry and exit. The valve body driving means for switching the second orifice passage between the communication state and the cutoff state is provided.

  In such a fluid-filled vibration isolator having a structure according to the present invention, the valve body is inserted into and removed from the second orifice passage from a direction substantially perpendicular to the passage direction. Therefore, under the state where the second orifice passage is blocked by the valve body, the hydraulic pressure applied through the second orifice passage is in a direction substantially orthogonal to the driving direction (in / out direction) of the valve body. Will be affected.

  Accordingly, when the second orifice passage is maintained in the shut-off state by the valve body, it is not necessary to counteract the hydraulic pressure to be applied, and the valve body can be held in the shut-off state with a relatively small valve body holding force. It becomes possible. In addition, even if a large pressure is applied to the valve body with the input of a large vibration load, the valve body can be stably maintained in the shut-off state, and the second orifice passage by the valve body can be maintained. Switching control between the communication state and the cutoff state can be realized stably.

  Furthermore, since the driving force required for the stable operation of the valve body may be relatively small, downsizing and energy saving of the actuator used as the valve body driving means can be achieved.

  Further, in the fluid filled type vibration damping device according to the present invention, the first orifice passage is formed by extending the outer peripheral portion of the partition member in the circumferential direction, while the second orifice passage is A structure formed by linearly extending the central portion of the partition member is preferably employed.

  According to this, the passage length of the first orifice passage can be obtained efficiently using the outer peripheral portion of the partition member, and the first orifice passage exhibits an effective vibration-proofing effect against low frequency vibration. Can be tuned to Further, the second orifice passage is formed by utilizing the central portion of the partition member in which the first orifice passage is not formed, so that the first orifice passage tuned to vibrations in different frequency ranges and the second orifice passage are formed. The orifice passage can be formed in a space efficient manner.

  In the fluid filled type vibration isolator according to the present invention, the flexible film is formed of a rubber elastic film, and the rubber elastic film is integrally formed with an elastic protrusion protruding into the equilibrium chamber. A structure in which the valve body is configured by inserting the elastic protrusion into the valve hole of the partition member is preferably employed.

  More preferably, the valve body driving means is disposed on the opposite side of the equilibrium chamber across the flexible membrane, and the output member of the valve body driving means is the flexible membrane in the flexible membrane. A structure in which the elastic protrusion is fixed from the outer surface is also adopted.

  According to the fluid-filled vibration isolator having such a structure, the valve element is configured using an elastic protrusion integrally formed with a flexible film (rubber elastic film). Therefore, the valve body can be formed without newly adopting a special member, and the structure can be simplified and the number of parts can be reduced.

  In the present invention, the working air chamber is provided with an output member on the wall that is displaced based on the change in internal pressure, and the output member is biased outward from the working air chamber. An urging means is provided, and the output member is displaced outwardly by the urging force of the urging means by allowing the working air chamber to communicate with the atmosphere, while applying a negative pressure to the working air chamber. Thus, the valve in which the output member adopts a pneumatic actuator that is retracted and displaced inwardly against the biasing force of the biasing means, and the valve body is driven and displaced by the output member of the pneumatic actuator. The structure which comprises the body drive means is employ | adopted suitably.

  According to this, for example, by using a pneumatic actuator having a simple structure that is driven by an urging means such as a coil spring and a negative pressure that can be easily obtained by an intake system of an engine in an automobile, Can be effectively realized. Therefore, in the fluid filled type vibration damping device, the structure can be simplified and the size of the device can be reduced.

  Further, in the present invention, the second mounting member is formed in a substantially cylindrical shape, the first mounting member is spaced apart on one opening side, and the one opening is fluidized by the main rubber elastic body. The other opening of the second mounting member is fluid-tightly closed with the flexible membrane, while the second elastic member between the main rubber elastic body and the flexible membrane is closed. The partition member is disposed so as to spread in a direction orthogonal to the central axis of the second mounting member, and the outer peripheral edge of the partition member is supported by the second mounting member, thereby sandwiching the partition member A structure in which the pressure receiving chamber and the equilibrium chamber are formed on both sides in the axial direction is preferably employed.

  According to this, the pressure receiving chamber and the equilibrium chamber can be formed in a space efficient manner, and the fluid filled type vibration damping device can be realized in a compact manner.

  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.

  1 to 3 show an automobile engine mount 10 as an embodiment of the present invention. The engine mount 10 has a structure in which a first mounting bracket 12 as a first mounting member and a second mounting bracket 14 as a second mounting member are elastically connected by a main rubber elastic body 16. The first mounting bracket 12 is mounted on the power unit side, and the second mounting bracket 14 is mounted on the body side of the automobile, so that the power unit is supported by the body against vibration. In the following description, the vertical direction basically means the vertical direction in FIG.

  More specifically, the first mounting member 12 has a substantially columnar shape, and a screw hole 18 that opens in the upper end surface and extends in the axial direction is formed in the central portion in the radial direction. A stopper plate 20 that extends in a direction perpendicular to the axis is integrally formed at the lower end portion. The first mounting member 12 having such a structure is adapted to be attached to the power unit side of the automobile by a bolt (not shown) screwed into the screw hole 18.

  The second mounting member 14 has a substantially stepped cylindrical shape as a whole, and has a large diameter portion 24 on the upper side in the axial direction with a step portion 22 formed in the intermediate portion in the axial direction. The lower side in the axial direction is a small diameter portion 26. Further, an inward projecting portion 28 that is bent inward in the direction perpendicular to the axis is formed at the opening edge of the second mounting member 14 on the small diameter portion 26 side.

  And the 1st mounting bracket 12 is arrange | positioned so that it may space apart in the axial direction upper direction on substantially the same central axis with respect to the opening part by the side of the large diameter part 24 in the 2nd mounting bracket 14, These 1st The mounting bracket 12 and the second mounting bracket 14 are elastically connected by a main rubber elastic body 16. The main rubber elastic body 16 has a substantially truncated cone shape as a whole, and a large-diameter recess 30 that opens to the center portion is formed on the large-diameter side end face. The main rubber elastic body 16 has a small-diameter side end face vulcanized and bonded to the lower end portion of the first mounting bracket 12, and a large-diameter side end outer peripheral surface of the main rubber elastic body 16 having a large diameter in the second mounting bracket 14. By being vulcanized and bonded to substantially the entire inner peripheral surface of the portion 24, it is formed as an integrally vulcanized molded product including the first mounting bracket 12 and the second mounting bracket 14. Further, the lower end surface of the outer peripheral portion of the main rubber elastic body 16 is vulcanized and bonded to the upper surface of the step portion 22 of the second mounting bracket 14. As a result, the upper opening of the second mounting member 14 is fluid-tightly closed by the main rubber elastic body 16.

  Note that a stopper rubber 32 protruding upward at the outer peripheral portion is integrally formed with the main rubber elastic body 16 on the stopper plate 20 of the first mounting member 12. Further, a seal rubber layer 34 integrally formed with the main rubber elastic body 16 is vulcanized and bonded to the inner peripheral surface of the small diameter portion 26 of the second mounting bracket 14.

  Further, a partition member 36 is fitted and assembled to the small diameter portion 26 of the second mounting bracket 14. The partition member 36 has a thick, substantially disk shape as a whole, and is formed using a hard material such as a metal material or a synthetic resin material. The partition member 36 includes a partition metal body 38 and a lid plate metal 40. The partition metal fitting main body 38 has a thick, substantially disk shape, and an upper locking groove 42 and a lower locking groove 44 extending in the circumferential direction are formed on the outer circumferential surface so as to be lined up and down in the axial direction. Yes. Further, a thin plate-shaped lid plate metal 40 is superimposed on the upper end surface of the partition metal body 38, and the partition member 36 in the present embodiment is constituted by the partition metal body 38 and the cover plate metal 40. Has been.

  The partition member 36 is inserted into the small-diameter portion 26 of the second mounting bracket 14, and the second mounting bracket 14 is subjected to a diameter reduction process such as an eight-way stop so that the second mounting bracket 14 has a reduced diameter. On the other hand, it is fixedly assembled. In particular, in the present embodiment, when the diameter of the second mounting bracket 14 is reduced, the inner protrusion 28 formed on the lower end portion of the second mounting bracket 14 is formed on the outer peripheral surface of the partition bracket main body 38. It is inserted into the stop groove 42 and locked. Thereby, the partition member 36 is fixed so as to spread in the direction perpendicular to the axis with respect to the second mounting bracket 14, and the outer peripheral surface of the upper portion of the partition member 36 above the upper locking groove 42 is the seal rubber layer 34. Is fluid-tightly superimposed on the inner peripheral surface of the second mounting bracket 14. Further, the partition member 36 is superimposed on the lower end surface of the main rubber elastic body 16 at the opening peripheral edge of the recess 30, and the partition metal body 38 and the cover plate metal 40 are substantially fixed in the axial direction. In addition, a diaphragm 46 as a flexible film is assembled to the lower end portion of the partition member 36.

  The diaphragm 46 is formed of a thin, substantially disc-shaped rubber elastic film that is sufficiently deformed to be easily deformed. Further, a fixed metal fitting 48 having a large-diameter substantially annular shape is vulcanized and bonded to the outer peripheral edge of the diaphragm 46. The fixing bracket 48 is externally attached to the lower end portion of the partition bracket main body 38 and is fixed to the partition member 36 by subjecting the fixing bracket 48 to diameter reduction processing such as an eight-way stop. In particular, in the present embodiment, a locking protrusion 50 extending inward in the radial direction is integrally formed at the upper end portion of the fixing metal 48, and the locking protrusion 50 is partitioned when the diameter of the fixing metal 48 is reduced. It is inserted into the lower locking groove 44 formed on the outer peripheral surface of the metal fitting body 38 and locked. As a result, the diaphragm 46 is fixed to the partition member 36, and thus the second mounting bracket 14, and the outer peripheral surface of the lower portion of the partition bracket body 38 than the lower locking groove 44 is connected to the diaphragm 46. It is fluidly superimposed on the inner peripheral surface of the fixing bracket 48 via a seal rubber layer 52 that is integrally formed and is attached to the inner peripheral surface of the fixing bracket 48.

  Then, the diaphragm 46 is assembled to the other opening (lower in FIG. 1) of the second mounting bracket 14 via the partition member 36, so that the axially lower opening of the second mounting bracket 14 is A diaphragm 46 covers the fluid tightly. As a result, a sealed region that is sealed with respect to the external space is formed between the axially opposed surfaces of the main rubber elastic body 16 and the diaphragm 46, and the incompressible fluid is sealed in the sealed region. A fluid chamber 54 is formed. As the sealed fluid sealed in the fluid chamber 54, for example, water, alkylene glycol, polyalkylene glycol, silicone oil, or the like is employed. In particular, in order to effectively obtain a vibration isolation effect based on the fluid flow action, it is desirable to employ a low viscosity fluid of 0.1 Pa · s or less as the sealed fluid. The incompressible fluid is sealed by, for example, assembling the partition member 36 and the diaphragm 46 to the integrally vulcanized molded product of the main rubber elastic body 16 having the first and second mounting brackets 12 and 14. This is realized by performing in a fluid.

  Further, since the partition member 36 is disposed between opposing surfaces of the main rubber elastic body 16 and the diaphragm 46 in the axial direction (upper and lower in FIG. 1), the partition member 36 is disposed inside the fluid chamber 54. The fluid chamber 54 is vertically divided into two by the partition member 36. As a result, a part of the wall portion is configured by the main rubber elastic body 16 on the one axial side (in FIG. 1, upper side) sandwiching the partition member 36, and the first mounting bracket 12 and the second mounting bracket 12. A pressure receiving chamber 56 is formed in which pressure fluctuations are caused by elastic deformation of the main rubber elastic body 16 when vibration is input between the mounting brackets 14. On the other hand, on the other side in the axial direction with respect to the partition member 36 (downward in FIG. 1), a part of the wall portion is constituted by a diaphragm 46, and volume change is easily allowed based on elastic deformation of the diaphragm 46. An equilibrium chamber 58 is formed. In addition, the lower side recess 60 opened in the center part is formed in the lower end surface of the partition metal fitting main body 38, and the volume of the equilibrium chamber 58 is advantageously ensured by the lower side recess 60 here. .

  A circumferential groove 62 extending in the circumferential direction with a predetermined length of a little less than one round is formed in the outer peripheral portion of the partition fitting main body 38. The circumferential groove 62 is opened upward in the axial direction, and the opening is covered fluid-tightly by the lid plate fitting 40, so that a tunnel-like flow path extending in a circumferential direction with a predetermined length is formed. Is formed. Further, the end of the tunnel-shaped flow path has a communication hole 64 formed so as to penetrate the lid plate metal 40 in the axial direction and a communication hole formed so as to penetrate the partition metal body 38 in the axial direction. 66 and the pressure receiving chamber 56 and the equilibrium chamber 58, respectively. Accordingly, the first orifice passage 68 that extends the outer peripheral portion of the partition member 36 in the circumferential direction by using the flow path formed by the circumferential groove 62 and allows the pressure receiving chamber 56 and the equilibrium chamber 58 to communicate with each other is formed. Is formed.

  In addition, a concave groove 70 linearly extending in one radial direction (left and right in FIG. 2) is formed in the central portion in the radial direction of the partition metal body 38. The concave groove 70 is opened upward in the axial direction, and the opening is covered fluid-tightly by the cover plate fitting 40, thereby forming a tunnel-like flow path linearly extending in one radial direction. ing. The end of the tunnel-shaped flow path includes a communication hole 72 formed so as to penetrate the lid plate metal 40 in the axial direction, and a communication hole 74 formed so as to penetrate the partition metal body 38 in the axial direction. The pressure receiving chamber 56 and the equilibrium chamber 58 are communicated with each other. As a result, by using the flow path formed by the concave groove 70, the central portion of the partition member 36 extends linearly in the direction perpendicular to the axis, and the second pressure chamber 56 and the equilibrium chamber 58 communicate with each other. An orifice passage 76 is formed. In the present embodiment, the second orifice passage 76 is formed so as to extend along the surface direction (perpendicular to the axis) of the partition member 36 over substantially the entire length. Is a control part over substantially the entire length.

  In the present embodiment, the resonance frequency of the fluid flowing through the first orifice passage 68 has an effective anti-vibration effect (high damping effect) based on the resonance action of the fluid of 10 Hz corresponding to an engine shake or the like. It is tuned so that it can be obtained against vibrations in the front and rear low frequency range. On the other hand, the resonance frequency of the fluid flowing through the second orifice passage 76 corresponds to an effective vibration isolation effect based on the resonance action of the fluid (vibration insulation effect based on the low dynamic spring characteristics) equivalent to idling vibration. It is tuned so as to be obtained with respect to vibrations in a high frequency range of about 40 Hz.

  In the engine mount 10 having such a structure, when vibration is input between the first mounting bracket 12 and the second mounting bracket 14 in a mounted state on the vehicle, the main rubber elastic body 16 is elastically deformed. As a result, pressure fluctuation is induced in the pressure receiving chamber 56. Then, based on the relative pressure difference between the pressure receiving chamber 56 and the equilibrium chamber 58 due to such pressure fluctuation, fluid flow through the first and second orifice passages 68 and 76 occurs between the two chambers 56 and 58. It can be tightened. Thereby, when the input vibration is a vibration in a low frequency range, an effective vibration isolation effect is exhibited by the fluid flow through the first orifice passage 68, while the input vibration is in a high frequency range. In the case of the above vibration, an effective vibration isolation effect is exhibited by the fluid flow through the second orifice passage 76.

  Here, the second orifice passage 76 has a valve penetrating the bottom wall portion in an intermediate portion (substantially central portion in the passage length direction in this embodiment) in the passage length direction (left and right in FIG. 2). A valve element insertion hole 78 as a hole is formed. As shown in FIGS. 1 and 2, the valve body insertion hole 78 extends in the axial direction with a substantially constant rectangular cross section, and the second orifice passage 76 is inserted in the middle of the valve body. It communicates with the equilibrium chamber 58 through a hole 78.

  The diaphragm 46 is integrally formed with a protruding valve body 80 as an elastic protrusion protruding upward in the axial direction at a substantially central portion in the radial direction. The protruding valve body 80 is formed to protrude in the axial direction with a substantially constant rectangular cross-sectional shape, and has a shape substantially corresponding to the valve body insertion hole 78. Further, the protruding valve body 80 is formed to protrude at a position corresponding to the position where the valve body insertion hole 78 is formed, and is inserted into the valve body insertion hole 78 from below in the axial direction. Thus, the valve body insertion hole 78 is substantially closed by the protruding valve body portion 80, so that the fluid flowing through the second orifice passage 76 is prevented from being short-circuited to the equilibrium chamber 58 through the valve body insertion hole 78. It has become. Furthermore, the protruding valve body portion 80 is inserted into the valve body insertion hole 78 so as to be able to enter and exit in the mount axis direction.

  Further, a pneumatic actuator 82 as a valve body driving means is disposed and assembled below the diaphragm 46 on the opposite side of the equilibrium chamber 58 with the diaphragm 46 interposed therebetween. The actuator 82 has a structure in which a pressing member 86 having a substantially hat shape as a whole is assembled to a thin, substantially cup-shaped housing fitting 84 in an accommodated state. The pressing member 86 includes a pressing fitting 88 as a substantially reverse cup-shaped output member, and a support rubber elastic body 90 that elastically connects and supports the pressing fitting 88 to the housing fitting 84.

  Specifically, the pressing fitting 88 is integrally formed with an annular plate-shaped flange 92 that extends radially outward from the peripheral edge of the opening. Further, the support rubber elastic body 90 spreads slightly in the axially downward direction radially outward from the covering portion 94 that covers the entire surface of the pressing fitting 88 and the flange portion 92 of the pressing fitting 88. An annular plate-shaped support portion 96 is provided, and a ring metal fitting 98 is vulcanized and bonded to the outer peripheral edge portion of the support portion 96. Furthermore, on the inner peripheral side of the pressing metal 88, a circular block-shaped elastic fitting part 102 that protrudes downward in the axial direction from the center portion of the upper bottom 100 of the pressing metal 88 is integrated with the support rubber elastic body 90. Is formed.

  A ring metal fitting 98 fixed to the outer peripheral edge of the support rubber elastic body 90 is fitted into the housing metal fitting 84 and is fitted and fixed to the lower end portion of the cylindrical wall portion 104 of the housing metal fitting 84. Thereby, the pressing metal fitting 88 is elastically supported with respect to the housing metal fitting 84 by the support portion 96 of the support rubber elastic body 90. Further, the space defined between the diaphragm 46 and the housing fitting 84 is fluid-divided into the bottom wall portion 106 side and the opening portion side of the housing fitting 84 by the pressing member 86, so that the pressing member An air chamber 108 that allows deformation of the diaphragm 46 is formed between the pressure member 86 and the diaphragm 46, and a sealed working air chamber 110 is formed between the pressing member 86 and the bottom wall portion 106 of the housing fitting 84. ing.

  Further, a connection port 112 is attached through substantially the center of the bottom wall portion 106 of the housing fitting 84 so that air pressure can be applied to the working air chamber 110 from the outside through the connection port 112. It has become.

  Further, the working air chamber 110 accommodates a coil spring 114 as urging means, one end of which is externally fitted to the elastic fitting portion 102 of the support rubber elastic body 90 and the other end. Is externally fitted to the support protrusion 116 projecting from the center of the bottom surface of the housing fitting 84, so that it is disposed across the bottom wall portion 106 of the housing fitting 84 and the upper bottom portion 100 of the pressing fitting 88. Yes. As a result, the urging force of the coil spring 114 is constantly applied to the pressing fitting 88 in a direction away from the bottom wall portion 106 of the housing fitting 84.

  In such an actuator 82, the flange-shaped portion 118 formed integrally with the peripheral edge of the opening of the housing fitting 84 is superimposed on the stepped portion 22 of the second mounting fitting 14 and positioned in the axial direction. Of the second mounting bracket 14 are externally attached to the small-diameter portion 26 of the second mounting bracket 14 and the fixing bracket 48 fixed to the diaphragm 46. It is fixedly attached to the metal fitting 14. Further, in the assembled state of the actuator 82, the upper bottom portion 100 of the pressing fitting 88 is overlapped and fixed to the radial center portion of the diaphragm 46 from below in the axial direction. The diameter of the ring fitting 98 is reduced by subjecting the housing fitting 84 to a diameter reduction process, and the supporting rubber elastic body 90 fixed to the inner peripheral surface of the ring fitting 98 is pre-compressed in the radial direction. Yes. Thereby, the effect | action of the tensile stress with respect to the support rubber elastic body 90 can be reduced, and durability can be aimed at.

  In the actuator 82, the external conduit 120 is connected to the connection port 112 in a state where the engine mount 10 is mounted on the automobile, and the switching valve 122 connected to the external conduit 120 is switched. By operating it, the atmosphere and the negative pressure source 124 can be selectively connected to the connection port 112. Further, the switching valve 122 is switched under the control of a controller (not shown) that outputs a switching signal corresponding to the traveling state of the automobile, so that the external conduit 120 is selectively selected from the atmosphere and the negative pressure source 124. Switching connection is made. Thereby, the atmospheric pressure and the negative pressure are selectively exerted on the working air chamber 110. As the negative pressure source 124, for example, a negative pressure generated in an air intake portion of an internal combustion engine of an automobile is used, a negative pressure generating pump is provided, or a negative pressure tank is additionally installed as necessary. This is advantageously realized.

  The pressure fitting 88 can be driven and displaced in the axial direction by switching and controlling the pressure in the working air chamber 110 of the actuator 82. The central portion of the diaphragm 46 superimposed on the bottom 100 is displaced in the axial direction. As a result, the protruding valve body 80 formed on the upper surface of the central portion of the diaphragm 46 can be displaced into and out of the valve body insertion hole 78 formed in the partition member 36. By driving the valve body insertion hole 78 in the exit / entry direction, the communication state and the shutoff state of the second orifice passage 76 are switched. In short, in the present embodiment, the valve body is constituted by the protruding valve body portion 80 that is inserted into the valve body insertion hole 78 and driven and displaced in the direction of entry and exit, and the protruding valve body portion 80 is driven and displaced. The valve body driving means is configured by the pressing fitting 88 of the actuator 82, and the projecting valve body portion 80 is driven and displaced by the actuator 82, so that the second orifice passage 76 is switched between the communication state and the cutoff state. It has become.

  That is, when vibration in a low frequency range such as an engine shake is input to the engine mount 10, the external conduit 120 is opened to the atmosphere, and the pressure in the working air chamber 110 becomes substantially atmospheric pressure. To be controlled. When the atmospheric pressure is applied to the working air chamber 110 in this way, the pressing fitting 88 is elastically protruded upward by the urging force of the coil spring 114, and the upper bottom portion of the pressing fitting 88. 100 pushes up the diaphragm 46 and presses the central portion of the diaphragm 46 against the center of the lower surface of the partition member 36. As shown in FIG. 1, a projecting valve body portion 80 that is formed to project from the upper surface of the central portion in the radial direction of the diaphragm 46 opens to the lower surface of the partition metal body 38 and opens the second orifice passage 76. It is inserted from below in the axial direction into the valve body insertion hole 78 formed in the intermediate portion, and the projecting tip surface of the projecting valve body 80 is brought into contact with the lower surface of the lid plate metal fitting 40. Yes. Note that the protruding valve body portion 80 in the present embodiment has substantially the same cross-sectional shape as the opening shape of the valve body insertion hole 78 and is positioned below the valve body insertion hole 78 in the axial direction.

  As a result, the protruding valve body 80 is inserted in a direction perpendicular to the fluid flow direction (left and right in FIG. 1) in the second orifice passage 76, and the protruding valve body 80 causes the second The orifice passage 76 is substantially blocked at the longitudinal intermediate portion. On the other hand, the communication hole 66 that allows the first orifice passage 68 to communicate with the equilibrium chamber 58 is formed at a position away from the contact portion of the diaphragm 46 that is pressed by the pressing fitting 88, thereby the first orifice. The passage 68 is always maintained in a communicating state. Therefore, by preventing the fluid flow through the second orifice passage 76, the fluid pressure fluctuation in the pressure receiving chamber 56 can be effectively secured, and the amount of fluid that can flow through the first orifice passage 68 is advantageously obtained. I can do it. Therefore, an excellent vibration isolation effect can be advantageously obtained based on the resonance action of the fluid that can flow through the first orifice passage 68 tuned to the low frequency range.

  Further, when vibration in a high frequency range such as idling vibration is input to the engine mount 10, the external conduit 120 is connected to the negative pressure source 124, and the pressure in the working air chamber 110 becomes negative. It is controlled to become. When the negative pressure is applied to the working air chamber 110 in this manner, the pressing fitting 88 is pulled and displaced toward the working air chamber 110 (downward in FIG. 1) against the urging force of the coil spring 114. Thus, the central portion of the diaphragm 46 is displaced away from the lower surface of the central portion of the partition member 36 in the axial direction. As shown in FIG. 3, the protruding valve body 80 is displaced downward in the axial direction while being inserted into the valve body insertion hole 78 formed in the partition metal body 38, so that the protruding valve body The protruding front end surface of the portion 80 is separated from the lower surface of the lid plate metal 40 in the axial direction.

  As a result, fluid can flow through the axially facing surface between the projecting tip surface of the projecting valve body 80 and the lower surface of the cover plate metal 40, and the second orifice passage 76 forms the pressure receiving chamber 56 and the equilibrium chamber 58. Are opened to communicate with each other. On the other hand, the first orifice passage 68 tuned to the low frequency range is substantially closed due to the antiresonant action of the fluid when the vibration is input in the frequency range higher than the tuning frequency. Therefore, the fluid pressure in the pressure receiving chamber 56 is effectively ensured without escaping through the first orifice passage 68, and the amount of fluid flow through the second orifice passage 76 tuned to a high frequency region is advantageously obtained. I can do it. Therefore, it is possible to advantageously obtain an anti-vibration effect based on the resonance action of the fluid flowing through the second orifice passage 76. In this embodiment, since the protruding valve body 80 is displaced in the axial direction without being extracted from the valve body insertion hole 78, the valve body insertion hole 78 is always moved by the protruding valve body 80. It is blocked. Therefore, it is possible to prevent the fluid flowing through the second orifice passage 76 from being short-circuited to the equilibrium chamber 58 through the valve element insertion hole 78, and based on the fluid flow action in the second orifice passage 76. The anti-vibration effect in the intended tuning frequency range is effectively exhibited.

  In the automobile engine mount 10 having the structure according to the present embodiment, the protruding valve body portion 80 that blocks the second orifice passage 76 has a passage direction of the second orifice passage 76 (in FIG. ) In a direction orthogonal to (in FIG. 1, the bottom). Thereby, when the second orifice passage 76 is blocked by the protruding valve body portion 80, the hydraulic pressure acting on the protruding valve body portion 80 through the second orifice passage 76 is increased in the driving direction of the protruding valve body portion 80. On the other hand, it is exerted in a direction substantially perpendicular to it. Therefore, it is possible to avoid the state in which the second orifice passage 76 is blocked by the protruding valve body 80 being released by the action of the hydraulic pressure. Accordingly, it is possible to stably and advantageously obtain a vibration isolation effect based on the fluid flow action in the plurality of orifice passages 68 and 76. In addition, the second orifice passage 76 can be maintained in the cutoff state without being affected by the hydraulic pressure, and the protruding valve body 80 can be held at the cutoff position with a relatively small holding force.

  Further, since it is not necessary to operate the protruding valve body 80 against the hydraulic pressure, the second orifice passage 76 is stably shut off even when the driving force of the actuator 82 is relatively small. I can do it. Therefore, even when a special negative pressure source for advantageously obtaining the driving force of the actuator 82 is not prepared, the actuator 82 having a compact and simple structure that uses a negative pressure such as an intake system of the engine can be used. The opening / closing operation of the portion 80 can be realized stably.

  In addition, the first orifice passage 68 tuned to the low frequency region is formed using the circumferential groove 62 extending in the circumferential direction on the outer peripheral portion of the partition member 36, and the second tuned to the high frequency region. The orifice passage 76 is formed by using a concave groove 70 extending in the radial direction at the radial center portion of the partition member 36. Thus, the first and second orifice passages 68 and 76 tuned to different frequency ranges are formed with good space efficiency in the outer peripheral portion and the inner peripheral portion of the partition member 36. Therefore, the engine mount 10 that exhibits an excellent anti-vibration effect against vibrations in a plurality of frequency ranges can be realized in a compact manner.

  In addition, the communication state and the cutoff state of the second orifice passage 76 are switched by driving the protruding valve body 80 by the actuator 82, and the switching control is performed in accordance with the vibration frequency of the input vibration. It has become. Therefore, in the plurality of orifice passages 68 and 76 tuned to different frequency ranges, the vibration isolation effect against the input vibration in the tuning frequency range can be more effectively exhibited. In particular, at the time of vibration input in the low frequency range, the hydraulic pressure in the pressure receiving chamber 56 escapes through the second orifice passage 76 by closing the second orifice passage 76 tuned to the high frequency range. Therefore, it is possible to advantageously obtain the amount of fluid flow in the first orifice passage 68 tuned to a low frequency range, and to resonate the fluid flowed through the first orifice passage 68. The anti-vibration effect based on it is exhibited more advantageously.

  As mentioned above, although one 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 above-described embodiment, the protruding valve body portion 80 formed integrally with the diaphragm 46 is employed as the valve body. However, the valve body does not necessarily have to be formed integrally with the diaphragm 46 and is provided as a separate member. May be. Specifically, for example, the diaphragm has a substantially annular plate shape, and a disk-shaped plate portion formed of a synthetic resin material or the like is formed at the center portion, and protrudes upward from the upper surface of the plate portion. It is also possible to form the valve body as described above. As is clear from this example, the valve body does not necessarily need to be formed of a rubber elastic body, and may be formed of a metal material, a synthetic resin material, or the like.

  Further, the protruding valve body 80 (valve body) is inserted from a direction orthogonal to the passage direction of the second orifice passage 76 to stably shut off the second orifice passage 76. Although it is desirable to have a rectangular cross section as shown in the embodiment, the shape of the protruding valve body is not limited in any way by the specific description of the embodiment.

  Further, the drive direction of the valve element does not necessarily have to be the mount axis direction. Specifically, for example, a valve hole (valve element insertion hole) is formed in the side wall portion of the second orifice passage 76, and the valve hole is applied from a direction perpendicular to the axis perpendicular to the passage direction of the second orifice passage 76. Alternatively, a valve body (protruding valve body portion) may be inserted into the second orifice passage 76 so that the communication state and the shut-off state of the second orifice passage 76 are switched.

  In the above-described embodiment, the pneumatic actuator 82 that is driven by selectively causing atmospheric pressure and negative pressure to act on the working air chamber 110 is employed as the valve body driving means. The present invention is not construed as being limited by the description in the embodiment, and various known actuators such as an electromagnetic actuator can also be employed.

  Further, the first orifice passage 68 and the second orifice passage 76 are as shown in the above-described embodiment in order to advantageously realize improvement of space efficiency and securing the passage length of the first orifice passage 68. In addition, it is desirable that the first orifice passage 68 is formed so that the outer peripheral portion of the partition member 36 extends in the circumferential direction, and the second orifice passage 76 is formed in the central portion in the radial direction of the partition member 36. However, the first and second orifice passages 68 and 76 are not necessarily formed in the shape and arrangement shown in the above-described embodiment, and can be freely arranged in various passage shapes.

  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.

FIG. 3 is a diagram showing a state in which atmospheric pressure is exerted on the working air chamber in the automobile engine mount as one embodiment of the present invention, corresponding to a cross section taken along line II in FIG. 2. The II-II sectional view taken on the line of the engine mount in FIG. FIG. 3 is a view showing a state where a negative pressure is exerted on the working air chamber in the engine mount, and is a cross-sectional view taken along line III-III in FIG. 2.

Explanation of symbols

10 engine mount, 12 first mounting bracket, 14 second mounting bracket, 16
Main rubber elastic body, 36 partition member, 46 diaphragm, 56 pressure receiving chamber, 58 equilibrium chamber, 68 first orifice passage, 76 second orifice passage, 78 valve body insertion hole, 80 projecting valve body portion, 82 actuator, 86 Press member, 88 press fitting, 90 support rubber elastic body, 110 working air chamber, 114 coil spring

Claims (6)

The first mounting member and the second mounting member are connected by a main rubber elastic body, and the partition member is supported by the second mounting member, and the main rubber elastic body is disposed on one side of the partition member. A part of the wall is formed to form a pressure receiving chamber for receiving vibration, and the other side of the partition member is a flexible membrane with a part of the wall formed of a variable volume balance. Forming a chamber, enclosing an incompressible fluid in the pressure receiving chamber and the equilibrium chamber, and forming an orifice passage communicating the pressure receiving chamber and the equilibrium chamber with each other. In the fluid-filled vibration isolator that obtains the vibration isolation effect based on the flow action,
As the orifice passage, a first orifice passage tuned to a low frequency range and a second orifice passage tuned to a high frequency range are provided, and a control portion extending inside the partition member is provided in the second orifice passage. And a valve hole that opens to the balance chamber in the wall of the control portion, and is made to be able to enter and exit the valve hole and is inserted into the valve hole, thereby the second orifice passage. And a valve body drive means for switching the second orifice passage between the communication state and the cutoff state by displacing the valve body in the direction of entering and exiting the valve hole. A fluid-filled vibration damping device.   The first orifice passage is formed by extending the outer peripheral portion of the partition member in the circumferential direction, while the second orifice passage is formed by extending the central portion of the partition member linearly. The fluid-filled vibration isolator according to claim 1.   The flexible film is formed of a rubber elastic film, and an elastic protrusion protruding into the equilibrium chamber is integrally formed on the rubber elastic film, and the elastic protrusion is formed in the valve hole of the partition member. The fluid-filled vibration damping device according to claim 1, wherein the valve body is configured by being inserted into the valve.   The valve body driving means is disposed on the opposite side of the equilibrium chamber with the flexible film interposed therebetween, and an output member of the valve body driving means is located at a portion where the elastic protrusion is formed on the flexible film. The fluid-filled vibration isolator according to claim 3, which is fixed to the outer surface.   A working air chamber provided with an output member is provided on a wall portion that is displaced based on a change in internal pressure, and a biasing means for biasing the output member outward from the working air chamber is provided. By connecting the working air chamber to the atmosphere, the output member is projected and displaced outward by the urging force of the urging means, while applying a negative pressure to the working air chamber causes the output member to Claims comprising a valve actuator that employs a pneumatic actuator that is retracted inwardly against the biasing force of the biasing means, and that drives and displaces the valve body with the output member of the pneumatic actuator. Item 5. The fluid filled type vibration damping device according to any one of Items 1 to 4. The second mounting member has a substantially cylindrical shape, the first mounting member is spaced apart on one opening side of the second mounting member, and the one opening is fluid-tightly closed by the main rubber elastic body. The other opening of the second mounting member is fluid-tightly closed with the flexible membrane, while the central axis of the second mounting member is between the opposing surfaces of the main rubber elastic body and the flexible membrane. The partition member is disposed so as to spread in a direction orthogonal to the outer periphery, and the outer peripheral edge of the partition member is supported by the second mounting member, so that the pressure receiving is received on both sides in the axial direction across the partition member. The fluid filled type vibration damping device according to claim 1, wherein a chamber and the equilibrium chamber are formed.

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