JP4820793B2 - Fluid filled vibration isolator - Google Patents

Description

  The present invention relates to a vibration isolator which is interposed between members constituting a vibration transmission system and elastically supports or elastically connects these members to each other. In particular, the present invention utilizes the flow action of a fluid sealed inside. The present invention relates to a fluid-filled vibration isolator that exhibits a desired vibration isolating effect.

  Conventionally, as a means for anti-vibration connection of one member to be anti-vibration connected to the other member, for example, an anti-vibration structure having a structure in which a first attachment member and a second attachment member are connected to each other by a main rubber elastic body. Shaking devices are known. In addition, in order to obtain an excellent anti-vibration effect against vibration in a specific frequency range, which is a problem, the fluid enclosed inside is allowed to flow between the two chambers through an orifice passage communicating the pressure receiving chamber and the equilibrium chamber. A fluid-filled vibration isolator that utilizes the anti-vibration effect exerted is also generally known, and is adopted as, for example, an engine mount or a member mount for an automobile.

  By the way, in such a fluid-filled vibration isolator, abnormal noise and vibration may be a problem when a shocking heavy load is input. Specifically, for example, when a fluid-filled vibration isolator is used as an engine mount of an automobile, the vibration or abnormal noise that can be felt in the passenger compartment by running on an uneven wavy road, etc. May occur.

  Although the mechanism for generating such abnormal noise and vibration has not yet been fully clarified, it is considered that the cavitation phenomenon contributes to this abnormal noise and vibration. That is, a sudden and large elastic deformation of the main rubber elastic body due to the input of a shocking large load temporarily reduces the fluid pressure in the pressure receiving chamber significantly, thereby generating cavitation bubbles in the pressure receiving chamber and collapses the cavitation bubbles. The water hammer pressure that is generated when doing so is considered to be the cause of abnormal noise and vibration.

  Therefore, considering such an abnormal noise and vibration generation mechanism, for example, in Patent Document 1 (Japanese Patent No. 2805305), a slit is formed in a rubber film disposed so as to partition the pressure receiving chamber and the equilibrium chamber. A fluid-filled vibration isolator having the above structure has been proposed. In such a structure described in Patent Document 1, when an excessive negative pressure is generated in the pressure receiving chamber, the rubber film is sucked by the negative pressure and elastically deformed to open the slit, and the pressure receiving through the slit. The chamber and the equilibrium chamber are short-circuited with each other, and the cavitation phenomenon is prevented by quickly eliminating the negative pressure in the pressure receiving chamber.

  However, even the fluid-filled vibration isolator described in Patent Document 1 has some problems that cannot be solved yet. First, as shown in Patent Document 1, when a slit is formed in the rubber film separating the pressure receiving chamber and the equilibrium chamber, not only when a negative pressure is applied to the pressure receiving chamber but also a positive pressure is applied to the pressure receiving chamber. In addition, the slit may open and the pressure receiving chamber and the equilibrium chamber may be short-circuited. In this way, when a normal load that is subject to vibration isolation is input, if the slit opens and the hydraulic pressure in the pressure receiving chamber is released to the equilibrium chamber side, a sufficient amount of fluid flow through the orifice passage cannot be obtained. The vibration-proof performance that should be exhibited based on the fluid flow action may be reduced.

  As a means for solving such a problem, it may be possible to make the slit difficult to open by, for example, increasing the rigidity by making the rubber film thick and limiting the elastic deformation of the rubber film. However, if the rigidity of the rubber film is sufficiently increased, the desired vibration isolation effect can be realized, but the slit opening amount may not be sufficiently obtained even when an excessive negative pressure that should open the slit is generated. There is a problem that the effect of reducing the above-mentioned abnormal noise and vibration is reduced.

  As another problem, there is a decrease in productivity due to the formation of slits and a decrease in durability of the rubber film. That is, in the fluid-filled vibration isolator described in Patent Document 1, since it is necessary for the slit to be closed during normal vibration input, it is virtually impossible to form the slit simultaneously with the molding of the rubber film. Is possible. Therefore, after the rubber film is first vulcanized, a slit having the desired size and shape must be cut into the rubber film with a cutter or the like, and a special process is required for such processing. Become. Moreover, since the slit cannot be molded, there is a problem that it is difficult to stably set the shape and dimensions of the slit with high accuracy. In addition, with a slit that is simply cut with a cutter, the stress concentration at the end of the slit is large when the slit is opened and closed, and cracks are likely to occur at the end of the slit, making it difficult to obtain sufficient durability. There was also a problem.

Japanese Patent No. 2805305

  Here, the present invention has been made in the background as described above, and the problem to be solved is to prevent an excessive negative pressure from being generated in the pressure receiving chamber due to a short circuit between the pressure receiving chamber and the equilibrium chamber. In the obtained fluid-filled vibration isolator, the opening and closing of the short-circuiting channel is realized with high accuracy, and the desired original vibration isolating effect at the time of normal vibration input is exhibited and the impact load that causes cavitation is a problem. A fluid-filled type with a new structure that can effectively obtain the negative pressure elimination effect due to a short circuit at the time of input, and further prevent adverse effects on durability and decrease in productivity due to the provision of a short-circuit flow path The object is to provide a vibration isolator.

  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, the present invention is characterized in that the first mounting member and the second mounting member are connected by the main rubber elastic body, and a part of the wall portion is configured by the main rubber elastic body so that it is incompressible. A pressure receiving chamber in which a fluid is sealed and an equilibrium chamber in which a part of the wall is formed of a flexible membrane and in which an incompressible fluid is sealed are formed, and the pressure receiving chamber and the equilibrium chamber are mutually connected by an orifice passage. In the fluid-filled vibration isolator which is in communication, a rubber valve body film is disposed between the pressure receiving chamber and the equilibrium chamber so that the pressure of the pressure receiving chamber is exerted on one surface of the rubber valve body film and the rubber While allowing the pressure of the equilibrium chamber to be exerted on the other surface of the valve body membrane, the rubber valve body membrane is formed with a longitudinal short-circuit opening extending with a predetermined opening width, and the short-circuit opening is opened with an opening width. Both side edges sandwiched in the direction protrude to the pressure acting surface side of the pressure receiving chamber. An action member having an insertion window at a position corresponding to the action protrusion of the rubber valve body film is disposed on the pressure action surface side of the pressure receiving chamber with respect to the rubber valve body film. And is supported by the second mounting member, and can be displaced in the insertion direction by inserting the action protrusion of the rubber valve body film with respect to the insertion window of the action member. At least one of the abutting portions of the inner surface of the insertion window and the outer surface of the working projection of the rubber valve body film gradually approaches each other in the width direction toward the base side of the working projection and becomes narrower. As the inclined surface, the short-circuit opening opens to allow the pressure receiving chamber and the equilibrium chamber to communicate with each other while the working protrusion is displaced to the protruding side in the insertion window, while the working protrusion is The short-circuit port is guided by the inclined surface in a state of being displaced to the drawing side which is the base side in the insertion window. Together adapted to be busy, in the provision of the urging mechanism allowed to resiliently held in the position of the pull side and biases the said working projections on the pull side.

  In such a fluid-filled vibration isolator having a structure according to the present invention, when a shocking heavy load is input, the negative pressure exerted in the pressure receiving chamber is prevented or quickly eliminated, resulting in cavitation bubbles. It is possible to effectively prevent abnormal noise and vibration that are thought to occur. In addition, when a normal load (anti-vibration target load) is input, the sealed fluid in the pressure receiving chamber is short-circuited to the equilibrium chamber side to prevent the hydraulic pressure from being absorbed, thereby preventing the fluid based on the fluid flow through the orifice passage. The vibration effect can be obtained effectively.

  That is, in the fluid-filled vibration isolator according to the present invention, the acting protrusion formed on the rubber valve body film is short-circuited in a single state (stationary state) where no external force is exerted on the rubber valve body film. It is made into the shape which opposed at a predetermined distance in the opening width direction of the opening | mouth. Then, the pressure receiving chamber and the equilibrium chamber are short-circuited through the short-circuit port, so that the negative pressure in the pressure receiving chamber can be quickly eliminated.

  Therefore, in order to realize a target vibration-proofing effect at the time of normal load input, it is necessary that the short-circuit port is held in a closed state. Therefore, in the fluid-filled vibration isolator according to the present invention, the rubber valve body membrane is attached to the fluid-filled vibration isolator as a means for holding the short-circuited opening in a closed state in advance. An inclined surface in which at least one of the outer surface of the action protrusion provided on the valve body membrane and the inner surface of the insertion window provided on the action member is narrowed in the opening width direction of the short-circuit opening toward the base side of the action protrusion. The two special structures of the guide mechanism and the urging mechanism that urges and holds the action protrusion toward the base side are employed in combination.

  By having a structure having these, the working protrusions facing each other at a predetermined distance in the width direction of the short-circuit opening in a single state are gradually drawn along the inclined surface by being drawn to the base side by the biasing mechanism. Of each other in the opening width direction. Under the assembly of the rubber valve body membrane to the fluid-filled vibration isolator, the short-circuit port formed between these operating protrusions is maintained in a substantially closed state by the holding action of the biasing mechanism. ing.

  Further, by appropriately setting the urging force exerted on the acting projection by the urging mechanism, when an excessive negative pressure that causes cavitation is exerted on the pressure receiving chamber, the acting projection is not negative. By the action of the pressure, it is retracted and displaced toward the pressure receiving chamber side against the urging force of the urging mechanism. When the action protrusion is displaced toward the pressure receiving chamber in this way, the restraining force due to the guide action exerted on the action protrusion is released, and the short-circuit port is opened. Accordingly, the pressure receiving chamber and the equilibrium chamber are communicated with each other through the short-circuit port, and the negative pressure in the pressure-receiving chamber is eliminated by the flow of the sealed fluid into the pressure receiving chamber side through the short-circuit port.

  As described above, the short-circuit opening is stabilized by the urging force by the urging mechanism or the holding force and the guide action by the inclined surface when assembled to the fluid-filled vibration isolator in the stationary state and the normal load input state. In addition to being able to maintain the closed state, if excessive negative pressure occurs in the pressure receiving chamber, the negative pressure in the pressure receiving chamber is eliminated by pulling the operating protrusion to the pressure receiving chamber side by the action of the negative pressure and opening the short circuit port. You can do that.

  Furthermore, in the present invention, by utilizing the urging force by the urging mechanism and the guide action by the inclined surface, the short-circuit port can be closed when the rubber valve body membrane is assembled to the fluid-filled vibration isolator, In a single state of the rubber valve body film, the action protrusions may be spaced apart in the opening width direction of the short-circuit opening and the short-circuit opening may be opened. Accordingly, the short-circuit port can be formed simultaneously with the vulcanization molding of the rubber valve body film without forming the short-circuit port in the rubber valve body film by post-processing. Therefore, a special process for forming the short-circuit opening is not required, and the shape and dimensions of the short-circuit opening can be stably set with high accuracy by molding to realize the desired vibration-proof performance. Any reduction of abnormal cavitation noise can be realized effectively.

  Moreover, in the fluid-filled vibration isolator according to the present invention, the short-circuit port may have a shape extending linearly.

  With the short-circuit opening having a linearly extending shape, the short-circuit opening can be blocked more stably. Accordingly, the opening and closing of the short-circuit opening can be switched with high accuracy, and the reduction or prevention of noise and vibration considered to be caused by the intended vibration-proof performance and cavitation can be realized at the same time.

  Furthermore, in the fluid filled type vibration isolator according to the present invention, when the short-circuit opening having the linearly extending shape as described above is employed, the short-circuit opening extending linearly includes a plurality of straight lines extending so as to cross each other. It is desirable to be constituted by parts.

  According to this, it is possible to smoothly open and close the short-circuit opening, to realize the original vibration isolation effect at the time of normal load input, and to limit the abnormal noise and vibration caused by cavitation at the time of input of impact load. Can be realized more effectively.

  Furthermore, in the fluid-filled vibration isolator according to the present invention, when the short-circuit opening is constituted by a plurality of linear portions extending in an intersecting manner, the action protrusion in the rubber valve body film is a circular outer peripheral surface. The plurality of linear portions constituting the short-circuit opening are formed so as to intersect on the central axis of the working protrusion and extend in a direction orthogonal to the central axis. It is more desirable.

  Thus, the action protrusion has a circular outer peripheral surface, so that the whole action protrusion is elastically deformed so that the diameter of the action protrusion is reduced or increased by the guide action of the inclined surface. Therefore, the deformation of the working protrusion is realized more stably, and the narrowing or widening of the short-circuit opening composed of a plurality of straight portions extending so as to divide the working protrusion in the circumferential direction is smoother and more reliable. To be realized. Further, by forming a plurality of straight portions intersecting each other, the entire length of the short-circuit opening can be efficiently ensured in a narrow space of the rubber valve body membrane.

  In the fluid filled type vibration damping device according to the present invention, preferably, the inner surface of the insertion window in the working member is the inclined surface having a convex curved cross-sectional shape, and the outer surface of the working protrusion. Is the inclined surface having a linear cross-sectional shape, and the contact position of the inclined surface moves outward in the opening width direction of the short-circuit opening as the action protrusion is displaced to the protruding side in the insertion window. It is supposed to be.

  The inner surface of the insertion window and the outer surface of the action protrusion in the action member are inclined surfaces having specific cross-sectional shapes, respectively, and the contact points of these inclination surfaces are moved along with the displacement of the action protrusion. Thus, the opening amount of the short circuit opening can be progressively changed with the displacement of the action member toward the tip side (pressure receiving chamber side).

  That is, when the action member is slightly displaced from the state pulled into the base side by the urging mechanism that is in the closed state of the short-circuit port toward the projecting tip side, the short-circuit port does not cause a problem of fluid flow. It can be maintained in a substantially occluded state. Therefore, it is possible to prevent the short-circuit opening from being opened due to the input of the vibration-proof target load, and to effectively prevent the vibration-proof performance from being deteriorated due to the absorption of the hydraulic pressure in the pressure-receiving chamber.

  On the other hand, when a large negative pressure is exerted in the pressure receiving chamber and the working projection is greatly displaced toward the tip side, the shapes of the inner surface of the insertion window and the outer surface of the working projection and the movement of their contact positions As a result, the amount of expansion of the short circuit opening can be progressively increased. As a result, the short-circuit opening can be efficiently opened in a limited stroke in the protruding direction of the action protrusion, and the avoidance or reduction of the negative pressure can be effectively achieved.

  Further, in the fluid filled type vibration damping device according to the present invention, an end through-hole having a wide opening width and a smooth curved inner peripheral surface is formed at each tip of the short-circuit opening. Is desirable.

  By forming an end through hole at each tip of the short-circuit opening where cracking due to stress concentration is likely to be a problem, the stress concentration at the tip of the short-circuit opening is relaxed to reduce strain, thereby short-circuiting It is possible to improve the durability of the rubber valve membrane by suppressing the occurrence and elongation of cracks at the tip of the mouth.

  In the fluid filled type vibration damping device according to the present invention, a movable rubber film is disposed between the pressure receiving chamber and the equilibrium chamber, and the pressure of the pressure receiving chamber is exerted on one surface of the movable rubber film. And a hydraulic pressure absorption mechanism that absorbs pressure fluctuations in the pressure receiving chamber by applying the pressure of the equilibrium chamber to the other surface of the movable rubber film. The rubber valve body film can be formed by forming the short-circuit opening and the action protrusion on the movable rubber film.

  By providing such a hydraulic pressure absorbing mechanism, an effective anti-vibration effect is exhibited against vibrations in a wider frequency range. Moreover, since the rubber valve body film is configured by providing a short-circuit opening and an action protrusion with respect to the movable rubber film constituting the hydraulic pressure absorbing mechanism, the number of parts is increased by providing the hydraulic pressure absorbing mechanism. Can be prevented.

  In the fluid-filled vibration isolator according to the present invention, a pressing force in a direction of pressing the pressure acting surface side of the pressure receiving chamber is exerted by the acting member on an outer peripheral portion of the acting protrusion in the rubber valve body film. Accordingly, it is desirable that the urging mechanism is configured to urge the working protrusion toward the retracting side and elastically hold it at the position on the retracting side.

  Thus, by pressing the pressure acting surface side of the pressure receiving chamber of the rubber valve body film with the acting member, the urging mechanism can be configured with a small number of parts. Preferably, a pressing force is applied to the outer peripheral portion of the action protrusion over the entire circumference in the circumferential direction.

  Furthermore, in the fluid filled type vibration damping device according to the present invention, when the urging mechanism as described above is configured, the urging mechanism is disposed at the outer peripheral portion of the working protrusion in the rubber valve body film. A pressing protrusion that protrudes from at least one of the opposing surfaces of the valve body film and the action member toward the other may be provided, and a pressing force may be applied to the rubber valve body film by the pressing protrusion. .

  By providing such a pressing protrusion and exerting a pressing force on the rubber elastic film, the urging mechanism can be easily realized. Preferably, the pressing protrusion is integrally formed with the rubber valve body film or the action member. Moreover, it is desirable that the pressing protrusion is provided over the entire circumference.

  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 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 connected to each other by a main rubber elastic body 16. is doing. The first mounting bracket 12 is attached to a power unit of an automobile (not shown) that is one member to be vibration-proof connected, and the body of an automobile (not shown) that is the other member to which the second mounting bracket 14 is connected to be prevented. As a result, the power unit is supported by the vehicle body in a vibration-proof manner.

  1 shows the state of the engine mount 10 as a single unit before being mounted on the automobile, but in the present embodiment, in the mounted state, the shared support load of the power unit is in the mount axis direction (in FIG. 1, (Up and down). Therefore, in the mounted state, the first mounting member 12 and the second mounting member 14 are displaced in the axial direction toward each other based on the elastic deformation of the main rubber elastic body 16. In addition, under such a mounted state, main vibrations to be vibrated are input substantially in the mount axis direction. In the following description, unless otherwise specified, the vertical direction refers to the vertical direction in FIG.

  More specifically, the first mounting member 12 is made of metal such as iron or aluminum alloy, and has a substantially circular block shape. A mounting bolt 18 that protrudes upward from the upper end surface is integrally formed at the central portion of the first mounting bracket 12.

  The second mounting bracket 14 is a high-rigidity member formed of a metal such as iron or aluminum alloy, like the first mounting bracket 12, and has a thin cylindrical shape with a large diameter. . Further, a flange-like portion 20 is integrally formed on the upper end portion of the second mounting bracket 14 over the entire circumference.

  The first mounting bracket 12 and the second mounting bracket 14 are arranged so that the first mounting bracket 12 is spaced apart on the one opening side in the axial direction of the second mounting bracket 14. The main rubber elastic body 16 is interposed between the first mounting metal 12 and the second mounting metal 14, and the first mounting metal 12 and the second mounting metal 14 are the main rubber elastic body 16. Are interconnected.

  The main rubber elastic body 16 has a substantially frustoconical shape, and a large-diameter recess 22 having a mortar shape or a hemispherical shape opening downward is provided on the end surface on the large-diameter side. The small-diameter side end face of the main rubber elastic body 16 is vulcanized and bonded in a state where substantially the entire portion from the axially intermediate portion to the lower end portion of the first mounting member 12 is embedded. On the other hand, the outer peripheral surface of the main rubber elastic body 16 is vulcanized and bonded to the outer peripheral surface of the second mounting bracket 14 from the intermediate portion in the axial direction to the upper end portion thereof. Further, a thin seal rubber layer 24 integrally formed with the main rubber elastic body 16 is formed so as to cover almost the entire inner peripheral surface from the axially intermediate portion to the lower end portion of the second mounting bracket 14. . In other words, the main rubber elastic body 16 is formed as an integrally vulcanized molded product including the first mounting bracket 12 and the second mounting bracket 14, whereby the first mounting bracket 12 and the second mounting bracket 12 are attached. The metal fittings 14 are elastically connected to each other by the main rubber elastic body 16, and the opening on one axial direction (the upper side in FIG. 1) of the second mounting metal fitting 14 is fluid-tight by the main rubber elastic body 16. Is blocked.

  In addition, a diaphragm 26 as a flexible film is provided in the opening portion on the other axial direction (lower side in FIG. 1) of the second mounting bracket 14. The diaphragm 26 is made of a thin rubber film that can be easily deformed, and has a substantially disk shape that is slackened in the axial direction. A large-diameter cylindrical fixing ring 28 is vulcanized and bonded to the outer peripheral edge of the diaphragm 26, and the fixing ring 28 is fitted into the opening below the second mounting bracket 14, so that the second mounting bracket 14 is subjected to a diameter reduction process such as an eight-way drawing, so that the fixing ring 28 is fitted and fixed in close contact with the second mounting member 14 via a seal rubber layer 24 that is compressed and deformed in the radial direction. Yes.

  Thereby, the diaphragm 26 is fixed to the second mounting bracket 14, and the opening of the other axial direction other side (lower in FIG. 1) of the second mounting bracket 14 is fluid-tightly covered with the diaphragm 26. Between the axially opposing surfaces of the main rubber elastic body 16 and the diaphragm 26 inside the second mounting bracket 14, a fluid sealing region 30 that is sealed with respect to the external space is formed.

  A partition member 32 is disposed in the fluid sealing region 30 and is supported by the second mounting bracket 14. As shown in FIGS. 1 to 3, the partition member 32 has a thick, generally disc shape as a whole, and includes an upper partition metal 34 and a lower partition metal 36 as acting members. ing.

  The upper partition fitting 34 is a substantially disk-shaped member made of metal or hard synthetic resin. In addition, a central recess 38 that opens downward in the radial direction is formed in the central portion of the upper partitioning bracket 34. Moreover, the notch-shaped fitting recessed part 40 opened toward a lower side and an outer peripheral side is continuously formed in the outer peripheral edge part of the upper partition metal fitting 34 over the perimeter. In other words, the upper partition fitting 34 includes a central recess 38 and a fitting recess 40, and the central recess 38 and the fitting recess 40 are separated from each other by a partition wall 42 serving as a pressing projection, and the center in the radial direction. It is formed in the part and the outer periphery. Furthermore, a notch-shaped communication window 44 is formed in a part of the circumference on the outer peripheral edge portion of the upper partition fitting 34. The communication window 44 is formed so as to penetrate the upper wall portion of the fitting recess 40 in the thickness direction.

  The lower partition fitting 36 is a substantially disk-shaped member made of the same material as the upper partition fitting 34. Note that the upper and lower partition members 34 and 36 are not necessarily formed of the same material. An accommodation recess 46 that opens upward is formed in the central portion of the lower partition fitting 36. The housing recess 46 is a circular recess having a larger diameter and a deeper bottom than the central recess 38 formed in the upper partition metal 34, and is fitted to the outer peripheral edge of the upper partition metal 34. The inner peripheral side wall surface of the receiving recess 40 and the peripheral wall surface of the housing recess 46 formed in the central portion of the lower partition metal 36 are set at substantially the same position in the radial direction. In addition, a notch-shaped circumferential concave portion 48 that opens toward the upper side and the outer circumferential side is formed in the outer peripheral edge portion of the lower partition metal 36. The circumferential recess 48 is formed to continuously extend in a circumferential direction with a predetermined length of about 5/8. In other words, the lower partition fitting 36 has an accommodation recess 46 and a circumferential recess 48, and the accommodation recess 46 and the circumferential recess 48 separate the partition wall portion 50 from the radial central portion and the outer peripheral edge. It is formed in the part. Further, a notch-shaped communication window 52 is formed in a part of the circumference on the outer peripheral edge of the housing recess 46. The communication window 52 is formed so as to penetrate the lower wall portion of the circumferential recess 48 in the thickness direction at one end in the circumferential direction of the circumferential recess 48.

  A partition member 32 is configured including the upper and lower partition fittings 34 and 36. That is, the upper and lower partition fittings 34 and 36 are aligned in the radial direction and overlapped in the axial direction so that the partition wall portion 42 of the upper partition fitting 34 is press-fitted into the housing recess 46 of the lower partition fitting 36. As a result, the upper partition metal 34 and the lower partition metal 36 are fixed to each other. Thereby, the partition member 32 in this embodiment is comprised.

  Under the assembly of the upper and lower partition fittings 34, 36, a circumferential groove 54 is formed on the outer peripheral side of the partition wall portion 50 in the lower partition fitting 36. The circumferential groove 54 is formed by using a fitting recess 40 formed at the outer peripheral edge of the upper partition metal 34 and a circumferential recess 48 formed at the outer peripheral edge of the lower partition metal 36. That is, the partition between the partition 50 provided in the lower partition 36 and the circumferential end of the circumferential recess 48 is externally fitted and fixed to the fitting recess 40 formed in the upper partition 34. As a result, the upper opening of the circumferential recess 48 is covered by the upper side wall portion of the fitting recess 40, and the circumferential groove 54 that opens to the outer peripheral surface of the partition member 32 and extends in the circumferential direction by a predetermined length is formed. Yes. A communication window 44 formed in the upper partition metal 34 is formed at one end of the circumferential groove 54, and a communication window 52 formed in the lower partition metal 36 is formed at the other end of the circumferential groove 54. Is formed.

  Further, under the assembly of the upper and lower partition fittings 34, 36, the opening of the central recess 38 of the upper partition fitting 34 is covered with the lower partition fitting 36 and the opening of the receiving recess 46 of the lower partition fitting 36. Is covered with an upper divider 34. In addition, a predetermined gap 56 is formed between the lower end surface of the partition wall portion 42 in the upper partition fitting 34 and the bottom wall surface of the accommodation recess 46 in the lower partition fitting 36. As a result, an accommodation region 58 separated from the outside is formed between the upper partition metal 34 and the lower partition metal 36.

  Further, a through-hole 60 is formed through the portion of the upper partition 34 that constitutes the upper bottom wall surface of the accommodation area 58, in other words, the upper wall portion of the central recess 38. As shown in FIG. 2, the through holes 60 are formed in the outer peripheral portion of the upper side wall portion of the central recess 38, and a plurality of through holes 60 are formed at a predetermined distance in the circumferential direction. In the present embodiment, the through holes 60 are formed so as to extend in the circumferential direction with a length of a little less than ¼ circumference, and the four through holes 60 are formed on the circumference.

  Further, a through-hole 62 is formed through the portion of the lower partition metal 36 that constitutes the bottom wall surface of the accommodation area 58, in other words, the lower wall portion of the accommodation recess 46. As shown in FIG. 3, the through holes 62 are formed in the outer peripheral portion of the upper wall portion of the receiving recess 46, and a plurality of through holes 62 are formed at a predetermined distance in the circumferential direction. In the present embodiment, the through holes 62 have a substantially sector shape with rounded corners in plan view.

  Here, an insertion hole 64 is formed in a central portion in the radial direction of the upper partition metal fitting 34. The insertion hole 64 is a circular through hole, and penetrates the upper bottom wall portion of the central recess 38 in the thickness direction. In addition, a guide cylinder portion 66 that extends upward in the axial direction is formed at the opening peripheral edge portion of the insertion hole 64. The guide tube portion 66 has a substantially cylindrical shape, and is integrally formed with the upper partition fitting 34. Further, the inner peripheral surface of the guide tube portion 66 is an inner peripheral tapered surface 68 as an inclined surface that gradually decreases in diameter as it goes downward on the base end side. In the present embodiment, an insertion window 70 that penetrates the upper partition metal 34 in the axial direction is configured by the cooperation of the insertion hole 64 and the central hole of the guide tube portion 66.

  Prior to the assembly of the diaphragm 26 to the second mounting bracket 14, the partition member 32 is fitted in the axial direction from the opening below the second mounting bracket 14. A fixing ring 28 of the diaphragm 26 fitted in the second mounting bracket 14 is overlaid on the lower end portion of the lower partition bracket 36 of the partition member 32. Then, by subjecting the second mounting bracket 14 to diameter reduction processing such as an eight-way drawing, the outer peripheral surface of the partition member 32 is compressed and deformed in the direction perpendicular to the axis based on the diameter reduction deformation of the second mounting bracket 14. It is overlaid on the inner peripheral surface of the second mounting bracket 14 via the seal rubber layer 24.

  Thereby, the partition member 32 including the upper and lower partition fittings 34 and 36 is fixedly supported by the second attachment fitting 14, and the fluid sealing region 30 inside the second attachment fitting 14 is fluid-tight. Dividing into two. On one side of the fluid sealing region 30 across the partition member 32, a part of the wall portion is constituted by the main rubber elastic body 16, and a pressure receiving pressure is generated by the elastic deformation of the main rubber elastic body 16. A chamber 72 is formed, and on the other side, an equilibrium chamber 74 in which a part of the wall portion is constituted by the diaphragm 26 is formed.

  The pressure receiving chamber 72 and the equilibrium chamber 74 are filled with an incompressible fluid. As the sealing fluid, for example, water, alkylene glycol, polyalkylene glycol, silicone oil or the like is adopted, and in order to effectively obtain a vibration isolation effect based on a fluid action such as a resonance action of the fluid, 0.1 Pa · It is desirable to employ a low-viscosity fluid of s or less. The incompressible fluid is sealed in the pressure receiving chamber 72 or the equilibrium chamber 74, for example, the partition member 32 or the diaphragm for the integrally vulcanized molded product of the main rubber elastic body 16 including the first and second mounting brackets 12 and 14. This is preferably realized by performing the assembly of 26 in an incompressible fluid.

  In addition, the communication groove of the upper partition fitting 34 in which the circumferential groove 54 of the partition member 32 is fluid-tightly covered with the second mounting bracket 14 and one end portion in the circumferential direction of the circumferential groove 54 is aligned in the circumferential direction. 44, the other end in the circumferential direction of the circumferential groove 54 is connected to the equilibrium chamber 74 through the communication window 52 of the lower partition fitting 36. As a result, an orifice passage 76 extending in the circumferential direction with a predetermined length is formed on the outer peripheral side of the partition member 32, and the pressure receiving chamber 72 and the equilibrium chamber 74 are communicated with each other through the orifice passage 76. Between the chambers 72 and 74, fluid flow through the orifice passage 76 is allowed.

  In the present embodiment, the resonance frequency of the fluid that is caused to flow through the orifice passage 76 is effective against vibrations in a low frequency region around 10 Hz that corresponds to an engine shake or the like based on the resonance action of the fluid. It is tuned so that the damping effect is demonstrated. Tuning of the orifice passage 76 is performed by, for example, the rigidity of the wall springs of the pressure receiving chamber 72 and the equilibrium chamber 74, that is, the main rubber elastic body 16 corresponding to the amount of pressure change required to change the chambers 72 and 74 by a unit volume. It is possible to adjust the length and cross-sectional area of the orifice passage 76 while taking into consideration the characteristic values based on the respective elastic deformation amounts of the diaphragm 26 and the diaphragm 26. Generally, the pressure transmitted through the orifice passage 76 The frequency at which the phase of the fluctuation changes to bring about the resonance state can be grasped as the tuning frequency of the orifice passage 76.

  Here, a movable rubber valve element 78 as a rubber valve element film shown in FIGS. 4 and 5 is accommodated in the accommodating area 58 provided in the partition member 32. The movable rubber valve element 78 includes an action film part 80 and a valve element protrusion 82 as an action protrusion.

  The action film portion 80 is formed into a film shape formed of a rubber elastic body having a substantially disk shape as a whole, and spreads in a direction substantially perpendicular to the axis. In addition, the outer diameter of the working film portion 80 is slightly smaller than the inner diameter of the housing recess 46. Further, as shown in FIG. 4, the working film portion 80 in the present embodiment has a plurality of bent portions in the radial intermediate portion thereof, and is gradually positioned upward as it goes to the center side. It is inclined to.

  Here, a slit 84 as a short-circuit opening is formed in the central portion of the working film portion 80. The slit 84 is formed by a longitudinal cut extending linearly in a plan view, and is formed to linearly penetrate the central portion of the movable rubber valve element 78 in the thickness direction. In the present embodiment, two cuts having a shape extending linearly in the direction perpendicular to the axis are formed, and the two cuts are formed so as to intersect each other at a right angle. Thereby, in the central part of the movable rubber valve body 78, a slit 84 having a cross shape formed by cutting them is formed.

  Further, in the present embodiment, a crack preventing hole 86 as an end through hole is formed at the outer peripheral side end of the slit 84. The crack prevention hole 86 has a substantially constant cross-sectional shape and is formed so as to penetrate the action film portion 80 in the movable rubber valve body 78 in the axial direction. As shown in FIG. It has an arc shape extending at a predetermined length, and its inner peripheral surface is a curved surface that is smoothly connected to the inner surface of the slit 84.

  In addition, valve body protrusions 82 are provided at both side edges in the width direction of the respective cuts constituting the slit 84. The valve body protrusion 82 is a protrusion that rises upward in the axial direction from the radial center portion of the action film part 80, and is integrally formed with the action film part 80.

  More specifically, the valve body protrusion 82 has a base portion 88 that protrudes upward from the radial center portion of the working film portion 80. Each of the base portions 88 has a thin-walled small-diameter arc shape extending in the axial direction, and has a substantially cylindrical shape as a whole by combining the base portions 88 adjacent to each other in the circumferential direction with a notch constituting the slit 84 therebetween. It is like that. In the present embodiment, a small-diameter circular hole is formed through the central portion of the working film portion 80 in the radial direction, and the base 88 is formed so as to extend from the opening peripheral edge of the circular hole.

  Further, a valve portion 90 is integrally formed at the upper end of each base portion 88 in the valve body protrusion 82. Each valve portion 90 has a structure in which a rubber elastic body having a substantially frustoconical shape in the opposite direction is divided into four in the circumferential direction, and a base portion 88 extends downward from an end portion on the small diameter side. In other words, a slit 84 composed of two cuts intersecting on the central axis is formed on a rubber elastic body having a substantially frustoconical shape in the opposite direction, so that the rubber elastic body is slit 84. The rubber elastic bodies divided by the slit 84 and cut by the slits 84 form the respective valve portions 90.

  Moreover, the outer peripheral surface of the valve part 90 is made into the outer peripheral taper surface 92 as an inclined surface which becomes a small diameter gradually as it goes to the base 88 side from an axial direction intermediate part to a lower end part. In addition, a notch-shaped recess 94 is formed in the upper center portion of the valve portion 90, and the thickness of the valve portion 90 at the protruding tip portion is suppressed.

  Further, as shown in FIGS. 4 and 5, each valve portion 90 is provided with a slit 84 in a state where the movable rubber valve body 78 is not attached to the partition member 32, in other words, in a single state of the movable rubber valve body 78. Are spaced apart from each other and are opposed in the radial direction. In short, in the single state, the slit 84 is maintained in an open state.

  As shown in FIG. 1, the movable rubber valve element 78 having such a structure is accommodated in the accommodating region 58 and disposed inside the partition member 32. That is, the movable rubber valve body 78 is disposed on the same central axis with respect to the housing recess 46 formed in the lower partition metal fitting 36 so as to spread in the direction perpendicular to the axis. When the upper partition fitting 34 is assembled to the lower partition fitting 36 under the assembly of the movable rubber valve body 78 to the lower partition fitting 36 to the lower partition fitting 36, the working film portion 80 of the movable rubber valve body 78 is formed. The outer peripheral portion enters the gap 56 formed between the upper and lower partition fittings 34 and 36 and is sandwiched between the upper and lower partition fittings 34 and 36. As described above, the movable rubber valve element 78 is assembled to the partition member 32.

  Therefore, in the present embodiment, the radial intermediate portion of the working film portion 80 enters the gap 56 and is overlapped with the lower end surface of the partition wall portion 42 of the upper partition metal fitting 34. The action film portion 80 is pressed downward in the axial direction by the lower end surface of the partition wall portion 42, and the central portion is lowered in the axial direction by utilizing the elasticity of the action film portion 80 by the action of the pressing force. It is energized. Thereby, the urging mechanism in the present embodiment is configured using the elasticity of the action film portion 80. In the present embodiment, the portion where the working film portion 80 is superimposed on the lower end surface of the partition wall portion 42 is a tapered surface that is gradually inclined upward toward the inner peripheral side, and the inner peripheral edge portion of the partition wall portion 42. It is possible to prevent a decrease in the durability of the working film portion 80 and the like due to the corner portion being strongly pressed against the working film portion 80.

  Further, under the assembly of the movable rubber valve element 78, the movable rubber valve element 78 has an outer peripheral portion fixed to the partition member 32 and a central portion covering the opening of the central recess 38. Arranged and allowed to move upward in the axial direction. In the present embodiment, since the central portion of the movable rubber valve element 78 is separated from the bottom wall portion of the housing recess 46, a downward displacement in the axial direction can be slightly allowed.

  Further, in the present embodiment, a plurality of through holes 60 and 62 are formed in portions of the upper partition metal 34 and the lower partition metal 36 that constitute the upper and lower wall portions of the accommodation region 58. As a result, the pressure in the pressure receiving chamber 72 is exerted on one surface of the working film portion 80 through the through hole 60, and the pressure in the equilibrium chamber 74 is exerted on the other surface through the through hole 62. It is like that.

  Further, as shown in FIG. 6, the valve body protrusion 82 formed at the central portion of the movable rubber valve body 78 can be displaced in the axial direction with respect to the insertion window 70 formed in the upper partition metal fitting 34. Is inserted through.

  That is, under the assembly of the movable rubber valve element 78 to the accommodating region 58, the valve element protrusion 82 is located at the central portion of the upper partition metal member 34 positioned on the pressure receiving chamber 72 side with respect to the movable rubber valve element 78. The valve body protrusion 82 is positioned on the central axis of the insertion window 70.

  Then, the valve element protrusion 82 is inserted into the insertion window 70 in a state where the action film part 80 is assembled in the accommodating region 58, and the valve element 90, which is the end part on the tip side of the valve element protrusion 82, is inserted. The large-diameter side end is exposed in the pressure receiving chamber 72 through the insertion window 70. In the present embodiment, a hollow recess 94 is formed at the large-diameter side end of the valve portion 90, and the large-diameter side end of the valve portion 90 is thinned in the radial direction. As a result, the large-diameter side end of the valve portion 90 can be deformed so as to shrink in the radial direction and can be inserted through the insertion window 70.

  In this case, the frustoconical rubber elastic body formed by combining the valve portions 90 (the valve portion 90 in the closed state of the slit 84) has an outer diameter of the large-diameter side end portion which is the distal end side end portion of the insertion window 70. The outer diameter of the small-diameter side end that is the base end side end is smaller than the inner diameter of the insertion window 70, and the base is formed integrally with the lower end of the valve portion 90. The outer diameter of 88 is also smaller than the inner diameter of the insertion window 70. Further, the protruding height of the valve element protrusion 82 in the axial direction is set to be sufficiently larger than the axial length of the insertion window 70. Accordingly, the valve body protrusion 82 is inserted into the insertion window 70 so as not to be extracted, and is allowed to be displaced by a predetermined distance in the insertion window 70 in the axial direction.

  Further, when the movable rubber valve body 78 is attached to the partition member 32, the central portion of the working film portion 80 is urged downward in the axial direction by the urging mechanism as described above. Due to the urging force exerted on 80, the valve body protrusion 82 integrally formed at the central portion of the action film portion 80 is urged downward in the axial direction, and axial displacement within the insertion window 70 is allowed. The valve body protrusion 82 is retracted and displaced elastically by being moved toward the housing region 58 side, which is the base side, by the action of the urging force.

  In this way, the valve body protrusion 82 is retracted and displaced toward the base side, so that each valve portion 90 is displaced in the direction of diameter reduction by the guide action by the sliding contact between the inner peripheral tapered surface 68 and the outer peripheral tapered surface 92. To be sedated. The valve portions 90 are positioned in the axial direction and the radial direction by causing the valve portions 90 to contact each other in the facing direction. Here, the slits 84 formed between the valve portions 90 are held in a blocked state by the valve portions 90 being brought into contact with each other.

  In the present embodiment, the outer peripheral taper surface 92 constituting the outer peripheral surface of the valve portion 90 under the arrangement of the movable rubber valve element 78 in the accommodating region 58 is, as shown in FIG. Are overlapped with an inner peripheral tapered surface 68 constituting the inner peripheral surface. In the present embodiment, the inner peripheral tapered surface 68 and the outer peripheral tapered surface 92 are inclined surfaces corresponding to each other, in other words, inclined surfaces having the same inclination angle, and these surfaces 68 and 92 are mutually connected. The valve portion 90 is slidably displaced relative to the guide tube portion 66 in a state of being overlapped.

  Further, under the closed state of the slit 84, the portion extending from the axially intermediate portion to the lower end of the base portion 88 and the valve portion 90 in the valve body projecting portion 82 is separated from the inner peripheral surface of the insertion window 70 on the inner peripheral side. In this portion, a gap is provided between the valve element protrusion 82 and the insertion window 70.

  When the automobile engine mount 10 having the above-described structure is mounted on the automobile and vibrations in a low frequency range such as an engine shake which is a problem during driving are input, a relatively large pressure fluctuation occurs in the pressure receiving chamber 72. Be born. Here, the axial displacement of the valve portion 90 is suppressed to be sufficiently small, and the slit 84 is held in a closed state. Therefore, the flow amount of the fluid through the orifice passage 76 is effectively ensured by the difference in the relative pressure fluctuation generated between the pressure receiving chamber 72 and the equilibrium chamber 74, and the fluid action such as the resonance action of the fluid is achieved. Based on this, an anti-vibration effect (high damping effect) effective against low-frequency vibrations such as engine shake is exhibited.

  Furthermore, when the automobile travels over a step or travels on a road surface with large unevenness, an impact load is input between the first mounting bracket 12 and the second mounting bracket 14, and the main rubber elastic body 16 suddenly moves. If it is elastically deformed excessively or excessively, an excessive negative pressure is induced in the pressure receiving chamber 72. When this negative pressure is applied to the action film part 80 and the valve part 90 of the valve body protrusion 82, the action film part 80 has its own elastic force under the assembly of the movable rubber valve element 78 to the partition member 32. Since the elastic force is set to such an extent that it is sucked and elastically deformed against the pressure receiving chamber 72, the action film portion 80 is elastically deformed to the pressure receiving chamber 72 side when the impact load is input. The valve body protrusion 82 formed integrally with the membrane portion 80 is pushed and displaced toward the pressure receiving chamber 72 in the insertion window 70 as the action membrane portion 80 is elastically deformed.

  Here, when the valve element protrusion 82 is displaced to the front end side, the restraining force (guide action) applied to the valve part 90 by the contact between the inner peripheral tapered surface 68 and the outer peripheral tapered surface 92 is released. 7, the valve portion 90 is displaced so as to be separated from each other based on the elasticity of the movable rubber valve body 78 itself. Then, when the valve portions 90 are spaced apart from each other and opposed to each other, the slit 84 formed between the valve portions 90 is expanded in the width direction that is the opposite direction of the valve portion 90, and the slit 84 Is opened and held in communication.

  Further, one opening of the slit 84 that is in communication is communicated with the pressure receiving chamber 72, and the other opening is communicated with the equilibrium chamber 74 via the accommodating region 58, so that the pressure receiving chamber 72 and the equilibrium chamber are communicated. A short-circuit channel that communicates 74 with each other is formed by a slit 84. In this case, since the flow resistance of the short-circuit channel is sufficiently smaller than that of the orifice passage 76, the short-circuit channel is formed by the slit 84 in the communication state, so that the pressure receiving chamber 72 and the pressure-receiving chamber 72 are connected to each other. A fluid flow is generated between the equilibrium chambers 74 so that the negative pressure exerted on the pressure receiving chamber 72 is quickly eliminated.

  As is clear from the above description, in the automobile engine mount 10 according to the present embodiment, the closed state of the slit 84 can be stably maintained when vibration is not input and when normal vibration is input. Therefore, the desired vibration-proofing effect can be exhibited reliably. In addition, when a shocking heavy load is input due to overcoming a step or traveling on a road surface having relatively large unevenness, the opening operation of the slit 84 is realized with high accuracy, and the slit 84 is used. The negative pressure induced in the pressure receiving chamber 72 is eliminated as quickly as possible by the fluid flow through the short-circuit channel configured as described above.

  Further, in the movable rubber valve element 78 in the present embodiment, the valve portions 90 are spaced apart from each other and are in a state where the slit 84 is opened in a single state before assembly to the partition member 32. ing. Therefore, the slit 84 can be formed simultaneously when the movable rubber valve body 78 is vulcanized and molded by filling a molding die with a rubber material. Therefore, the formation process of the slit 84 can be omitted, and a high-quality movable rubber valve element 78 can be provided while suppressing manufacturing errors in the shape and dimensions of the slit 84.

  In particular, in the present embodiment, when the movable rubber valve body 78 is assembled to the partition member 32, the slit 84 that has been opened in advance is closed using the elastic force of the movable rubber valve body 78 itself. It has become. Therefore, the original vibration-proofing effect of the target engine mount 10 can be stably obtained without requiring a special member constituting the urging mechanism.

  Furthermore, in the present embodiment, the slits 84 are linearly extended, and the two slits 84 are formed so as to be orthogonal to each other at the center. As a result, four valve body protrusions 82 having a fan shape in a plan view are formed, and the entire valve body protrusions 82 are relatively displaced in the direction of diameter expansion or contraction, whereby the slit 84 Opening and closing operations are realized stably and reliably.

  In the present embodiment, the crack prevention holes 86 are formed at both ends of the linear cuts constituting the slit 84, the inner peripheral surface of the crack prevention hole 86 is a smooth curved surface, and The inner peripheral surface of the prevention hole 86 and the inner surface of the slit 84 are smoothly connected. As a result, the stress exerted on both ends of the slit 84 during the opening operation of the slit 84 is relieved, cracks generated due to stress concentration and the accompanying increase in strain are prevented, and the durability of the movable rubber valve element 78 is improved. Can be planned.

  Next, FIG. 8 shows an engine mount 96 for automobiles as a second embodiment of the fluid filled type vibration damping device according to the present invention. In the following description, members and portions that are essentially the same as those of the above-described embodiment are denoted by the same reference numerals in the drawings and description, and the description thereof is omitted.

  That is, the engine mount 96 according to this embodiment includes a partition member 98 as shown in FIGS. The partition member 98 includes an upper partition metal 100 and a lower partition metal 102.

  The upper partition fitting 100 is a hard member having a thin and large-diameter substantially disk shape. Further, four through-holes 104 are formed through the middle portion of the upper partition 100 in the radial direction. As shown in FIG. 9, the through holes 104 extend in the circumferential direction with a predetermined length of a little less than ¼ circumference, and are positioned at a predetermined distance from each other in the circumferential direction. Further, a notch-shaped communication window 44 is formed on the outer peripheral edge of the upper partition member 100. In the present embodiment, an annular recess that extends continuously in the circumferential direction is formed on the lower surface of the central portion of the upper partition member 100.

  Further, an insertion hole 64 penetrating in the thickness direction is formed in the central portion of the upper partitioning metal 100. The insertion hole 64 is a small-diameter circular hole and is formed so as to be separated from the through hole 104 on the inner peripheral side. Further, a guide tube portion 66 is formed at the opening peripheral edge portion of the insertion hole 64. The guide tube portion 66 has a substantially cylindrical shape extending linearly in the axial direction, and is provided integrally with the upper partition fitting 100 at the opening peripheral edge portion of the insertion hole 64. Further, the inner peripheral surface of the upper end portion of the guide tube portion 66 is an inner peripheral tapered surface 68 that gradually decreases in diameter downward.

  On the other hand, the lower partition fitting 102 has a thick and large-diameter substantially disk shape, and is a hard member formed of metal or a hard synthetic resin like the upper partition fitting 100. In addition, an accommodation recess 106 is formed in a central portion in the radial direction of the lower partition fitting 102. The housing recess 106 is a shallow circular recess and is formed so as to open at the upper end surface of the lower partition fitting 102. Further, on the outer peripheral side of the housing recess 106, a notch-shaped circumferential recess 48 is formed extending in the circumferential direction with a predetermined length. Furthermore, a communication window 52 penetrating the lower wall portion is formed at one circumferential end of the circumferential recess 48.

  Furthermore, a through hole 108 is formed in the outer peripheral portion of the bottom wall portion of the housing recess 106. As shown in FIG. 10, the through hole 108 has substantially the same shape as the through hole 104 formed in the upper partition metal fitting 100, and is formed to penetrate at a position corresponding to the through hole 104. A communication hole 110 is formed in the central portion of the bottom wall portion of the housing recess 106. As shown in FIG. 10, the communication hole 110 is a circular through hole, and is spaced apart from the through hole 108 on the inner peripheral side.

  And these upper and lower partition metal fittings 100 and 102 are aligned on the same central axis and overlapped with each other in the axial direction. Here, an accommodation region 112 is formed between the upper and lower partition members 100, 102. The accommodation area 112 is formed by covering the opening of the accommodation recess 106 formed in the lower partition fitting 102 with the central portion of the upper partition fitting 100. In addition, a circumferential groove 54 is formed on the outer peripheral side of the accommodation region 112 using a circumferential recess 48.

  Here, as shown in FIG. 8, the movable rubber film 114 is accommodated in the accommodation region 112. As shown in FIGS. 11 and 12, the movable rubber film 114 is a rubber film having a substantially disk shape as a whole, and includes a hydraulic pressure absorbing portion 116, a working film portion 118, and a valve body protrusion 120. It consists of

  The hydraulic pressure absorbing portion 116 is a rubber film having a substantially annular plate shape formed on the outer peripheral portion of the movable rubber film 114, and is thinner than the axial dimension of the accommodation region 112.

  Further, an annular fitting portion 122 is integrally formed on the outer peripheral edge portion of the hydraulic pressure absorbing portion 116. The annular fitting portion 122 has a substantially constant rectangular cross section, and has a shape protruding at both sides in the thickness direction at the outer peripheral edge portion of the hydraulic pressure absorbing portion 116. Further, an annular support portion 124 is integrally formed on the inner peripheral edge portion of the hydraulic pressure absorbing portion 116. The annular support portion 124 has substantially the same shape as the annular fitting portion 122, and has a shape that protrudes to both sides in the thickness direction at the inner peripheral edge portion of the hydraulic pressure absorbing portion 116. The annular fitting portion 122 and the annular support portion 124 have the same or slightly larger axial dimension than the axial dimension of the accommodation region 112.

  The working film part 118 in the present embodiment is a rubber film having a substantially disk shape, and is integrally formed so as to be located on the inner peripheral side of the annular support part 124. Further, as shown in FIG. 11, the working film portion 118 is gradually inclined upward as it goes to the center side. In addition, a slit 84 is formed in the central portion of the working film portion 118. The slit 84 extends to the intermediate portion in the radial direction of the working film portion 118. As is clear from FIGS. 11 and 12, the slit 84 in the present embodiment is also maintained in an open state when the movable rubber film 114 is in a single state, as in the first embodiment.

  In addition, a small-diameter circular hole is formed through the central portion of the working film portion 118, and a valve body protrusion 120 protruding upward is integrally formed at the opening peripheral edge of the circular hole. Four valve body protrusions 120 are provided so as to face each other across each linear cut forming the slit 84, and each has a base portion 88 and a valve portion 126.

  The base portion 88 has a substantially arc shape and is integrally formed with the inner peripheral edge portion of the working film portion 118. On the other hand, as shown in FIG. 12, the valve portion 126 has a substantially fan shape in a plan view, and has a structure in which the cross-sectional shape expands in a substantially similar shape toward the center in the axial direction. Further, a notch-shaped cutout recess 94 is formed at the inner peripheral edge of the upper end of the valve portion 126.

  The movable rubber film 114 having such a structure is disposed in the accommodation region 112 as shown in FIG. That is, the movable rubber film 114 is fitted into the receiving recess 106, the annular fitting portion 122 is positioned on the outer peripheral side of the through hole 108, and the annular support portion 124 is the diameter of the through hole 108 and the communication hole 110. Positioned between directions. Thereby, both the annular fitting part 122 and the annular support part 124 are positioned on the bottom wall part of the housing recess 106 over the entire circumference. Although not particularly limited, in this embodiment, the outer diameter of the annular fitting portion 122 is slightly larger than the inner diameter of the accommodation recess 106, and a slight compressive force is applied to the movable rubber film 114. It is designed to work. Thereby, the tensile stress acting on the movable rubber film 114 can be relaxed and durability can be improved.

  The upper partition metal fitting 100 is assembled to the lower partition metal fitting 102 in a state where the movable rubber film 114 is fitted into the housing recess 106 as described above. Under such assembling, the annular fitting portion 122 and the annular support portion 124 provided on the movable rubber film 114 are both pressed and abutted against the upper and lower partition fittings 100, 102. , 102 are compressed in the axial direction and supported by pinching.

  Further, the hydraulic pressure absorbing portion 116 formed on the outer peripheral portion of the movable rubber film 114 includes an upper bottom wall portion of the accommodation area 112 configured by the upper partition metal fitting 100 and an accommodation area 112 configured by the lower partition metal fitting 102. Between the opposing surfaces of the lower bottom wall part, it is located away from any of these wall parts. Thereby, the hydraulic pressure absorption part 116 is arrange | positioned in the state which supported the inner and outer both ends elastically, and the micro displacement in the axial direction is permitted.

  Further, the valve body protrusion 120 is inserted through the insertion window 70 formed in the upper partition metal fitting 100. In the present embodiment, the outer diameter of the entire valve portion 126 under the blockage of the slit 84 is larger than the inner diameter of the insertion window 70 in the axially intermediate portion, and is a portion that is larger than the inner diameter of the insertion window 70. However, it is positioned so as to protrude upward in the axial direction from the upper partition member 100 through the insertion window 70. Thereby, the valve body protrusion 120 is inserted into the insertion window 70 so as not to be extracted.

  In the present embodiment, as shown in FIG. 13, an annular pressing rubber 128 as a pressing protrusion is fixed to an annular recess formed on the lower surface of the upper partition metal fitting 100. The annular pressing rubber 128 continuously extends over the entire circumference with a substantially constant cross-sectional shape. The annular pressing rubber 128 may be fixed to the upper partition fitting 100 by post-bonding, but is vulcanized and bonded to the upper partition fitting 100 in this embodiment.

  The annular pressing rubber 128 is brought into contact with the action film portion 118 of the movable rubber film 114 under the arrangement of the movable rubber film 114 in the accommodation region 112. That is, the annular pressing rubber 128 is protruded downward from the lower surface of the upper partition metal 100 and is brought into contact with the surface of the working film portion 118 on the pressure receiving chamber 72 side. As a result, the working film portion 118 is pressed downward by the annular pressing rubber 128, and as shown in FIG. 13, the working film portion 118 is inclined so that the inner peripheral side gradually inclines from the contact portion. ing.

  Due to such elastic deformation of the action film portion 118, a biasing force acting downward is exerted on the valve body protrusion 120. The valve body protrusion 120 is pulled downward in the axial direction by being biased downward, and the valve body protrusion 120 is guided by the sliding action between the inner peripheral tapered surface 68 and the outer peripheral tapered surface 92. Is deformed in the direction of diameter reduction. As a result, as shown in FIG. 13, the valve portions 126 are brought closer to each other and come into contact with each other by the elasticity of the movable rubber film 114 itself, and the slit 84 is closed by the valve portion 126. As is clear from the above description, the urging force applied to the valve body protrusion 120 based on the elasticity of the movable rubber film 114 itself when the movable rubber film 114 is pressed by the annular pressing rubber 128. The urging mechanism in this embodiment is constituted by this.

  The partition member 98 provided with the movable rubber film 114 is accommodated in the fluid sealing region 30 and is fixedly supported by the second mounting member 14 as in the first embodiment. Here, the pressure in the pressure receiving chamber 72 is exerted on one surface of the movable rubber film 114 on the side where the valve body protrusion 120 protrudes. On the other hand, the pressure in the equilibrium chamber 74 is applied to the other surface of the movable rubber film 114.

  The engine mount 96 according to the present embodiment including the partition member 98 is interposed between the power unit and the body of the automobile, and prevents them mutually, like the engine mount 10 in the first embodiment. Swing connected.

  In the automobile engine mount 96 according to this embodiment, as in the first embodiment, an effective vibration-proofing effect due to the orifice effect is exhibited against vibration in a low frequency range corresponding to engine shake. Is done.

  Further, when an impact load is input due to stepping over a step or the like, the negative pressure in the pressure receiving chamber 72 acts on the movable rubber film 114 and the valve body protrusion 120 is displaced to the pressure receiving chamber 72 side. To be sedated. Thereby, as shown in FIG. 14, the valve portion 126 is displaced in the diameter-expanding direction to be separated from each other, and the slit 84 is opened. Then, the fluid flow is generated between the pressure receiving chamber 72 and the equilibrium chamber 74 through the short-circuit channel constituted by the opened slit 84, so that the negative pressure in the pressure receiving chamber 72 is quickly eliminated, and cavitation and The accompanying noise and vibration are prevented.

  Further, in the engine mount 96 according to the present embodiment, the movable rubber film 114 has the hydraulic pressure absorbing portion 116, and the pressure in the pressure receiving chamber 72 is exerted on one surface of the hydraulic pressure absorbing portion 116 through the through hole 104. In addition, the pressure in the equilibrium chamber 74 is applied to the other surface through the through hole 106. When medium to high frequency vibration corresponding to idling vibration is input between the first mounting bracket 12 and the second mounting bracket 14, the hydraulic pressure absorbing portion 116 is positively minutely deformed in a resonance state. As a result, a hydraulic pressure transmission action for transmitting minute pressure fluctuations in the pressure receiving chamber 72 to the equilibrium chamber 74 side is exhibited. Thereby, the high dynamic spring in the pressure receiving chamber 72 is prevented, and an effective anti-vibration effect with respect to vibration in the middle to high frequency range is exhibited.

  In particular, in the present embodiment, such a hydraulic pressure absorption mechanism is configured using a part of the movable rubber film 114 including the valve body protrusion 120. As a result, a hydraulic pressure absorbing mechanism can be realized without adding special parts and without adding an assembly process accompanying the addition of parts.

  Further, as shown in the present embodiment, a pressing protrusion (annular pressing rubber 128 in the present embodiment) made of a separate member is fixed to the upper partition metal fitting 100, and the working film portion An urging mechanism that exerts an urging force on the valve body protrusion 120 by pressing 118 can also be realized. In particular, as shown in the present embodiment, by forming the pressing protrusion with an elastic body such as an annular pressing rubber 128, it is possible to prevent the movable rubber film 114 from being damaged by pressing and to improve durability. I can do it.

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

  For example, in the first and second embodiments, the inner peripheral taper surface 68 and the outer peripheral taper surface 92 that are spread out with a certain inclination are shown as the inclined surfaces. 92 does not necessarily have a planar shape that spreads at a constant inclination.

  Specifically, for example, the protruding tip portion of the guide tube portion 130 has an arcuate curved cross section as in one aspect of the fluid-filled vibration isolator according to the present invention shown in FIGS. In addition, the inner peripheral tapered surface 132 can be configured by a convex arcuate curved surface that constitutes the inner peripheral surface of the protruding tip portion of the guide tube portion 130. According to this, the inner peripheral tapered surface 132 is brought into contact with the outer peripheral tapered surface 92 which is a flat inclined surface per line, and the smoothness of the valve portion 126 is reduced by reducing the frictional resistance during sliding. The displacement can be realized and the slit 84 can be opened and closed with high accuracy.

  In addition, in the structure shown in FIGS. 15 and 16, the inner peripheral tapered surface 132 has a convex curved cross section in the longitudinal cross section, and the outer peripheral tapered surface 92 has a linear cross section. By adopting such a structure, when the displacement amount of the valve body protrusion 82 toward the pressure receiving chamber 72 is relatively small, in other words, when the normal vibration is input, the separation distance between the valve portions 90 is relatively small. Thus, the slit 84 is maintained in a substantially closed state. Therefore, it is possible to prevent the fluid from being short-circuited through the slit 84 and obtain a target vibration-proofing effect. Here, the substantially closed state of the slit 84 includes an open state in which fluid flow through the slit 84 does not occur.

  On the other hand, when the displacement amount of the valve body protrusion 82 toward the pressure receiving chamber 72 increases, in other words, when shocking large amplitude vibration is input, as shown in FIG. The separation distance increases progressively, and the slit 84 is quickly shifted to a sufficiently open state. In particular, with the inner peripheral tapered surface 132 and the outer peripheral tapered surface 92 as a specific curved surface and a flat surface, the contact location is moved to the outer peripheral side with the displacement of the valve portion 90, so that the stroke of the valve body projection 82 is reduced. Thus, the opening width of the slit 84 can be obtained efficiently. Accordingly, the action of eliminating the negative pressure in the pressure receiving chamber 72 due to the short circuit of the fluid is effectively exhibited, and generation of abnormal noise and vibration can be advantageously prevented.

  In the first and second embodiments, a structure having two straight portions cut into a cross as a short-circuiting port is shown, but the short-circuiting port is, for example, one linearly extending It may be configured by cutting. That is, in the movable rubber valve element 134 employed in the fluid-filled vibration isolator as one aspect of the present invention shown in FIG. 17, a cut extending linearly in one radial direction in the central portion of the working film portion 80. A slit 136 is formed as a short-circuit opening formed by the above-described configuration, and a valve body protrusion 138 is formed so as to face the slit 136 in the opening width direction. The valve body protrusion 138 has a substantially semicircular shape in plan view, and combines a pair of the slits 136 in the width direction of the slit 136 to form a substantially frustoconical rubber elastic body. It has a base (not shown) extending from the lower end. Also in the movable rubber valve body 134 having the slit 136 configured by one notch extending linearly as described above, it is possible to obtain the same function and effect as in the first embodiment. Needless to say, the short-circuit opening may be formed by combining three or more cuts.

  Further, in the first and second embodiments, a slit configured by a linearly extending cut is shown as a short-circuit opening, but the short-circuit opening is curved at least partially in the middle portion in the longitudinal direction. It may be bent or bent. Further, the short-circuit port may be curved or bent in the axial direction.

  As shown in the first embodiment, the pressure of the pressure receiving chamber 72 is applied to one surface of the working film portion 80 to achieve smooth operation of the valve body protrusion 82. In order to achieve this, it is not always necessary that the pressure of the pressure receiving chamber 72 be applied to the working film portion 80, and the structure such as the through hole 60 shown in the first embodiment is not essential. Absent.

  In the first and second embodiments, the structure in which the inclined surface is configured on both the outer peripheral surface of the working protrusion and the inner peripheral surface of the insertion window is shown. It may be formed on the side. For example, as shown in FIG. 18, the outer peripheral surface of the valve element protrusion 82 as the action protrusion does not have an inclined surface, and a corner 142 is formed. A line contact may be made with respect to the circumferential taper surface 68.

  In the first and second embodiments, the inner surface of the insertion window has a circular inner peripheral surface shape, and the insertion window has a circular window shape. However, the structure of the insertion window is not limited to such a circular shape. Specifically, for example, the insertion window has a substantially rectangular window shape, and an inclined portion in which the facing portion on the inner peripheral surface of the insertion window gradually approaches as it goes to the base side of the working protrusion inserted through the insertion window. It may be a surface. In addition, when adopting such a rectangular window-shaped insertion window, only a pair of portions facing each other on the inner peripheral surface of the insertion window may be inclined surfaces, or all of which constitute the inner peripheral surface This part may be an inclined surface. Further, the shape of the outer peripheral surface of the action protrusion is not particularly limited, and particularly when the rectangular insertion window having the above structure is employed, the outer shape of the action protrusion is the inner periphery of the insertion window. It is desirable to have a shape corresponding to the surface shape, and the action protrusion may be a rectangular column shape or the like.

  In the first and second embodiments, both the movable rubber valve body 78 and the movable rubber film 114 have a movable film structure in which at least the outer peripheral edge portion is fixedly supported by the partition member 32. However, the rubber valve body film and the movable rubber film are accommodated in the accommodation area without being fixedly supported by any member including a partition member, for example, and are slightly displaced in the axial direction in the accommodation area. Thus, the movable plate structure may be configured such that the pressure in the pressure receiving chamber can be transmitted to the equilibrium chamber side.

  In addition, the pressing protrusion shown in the second embodiment does not necessarily have to be configured as a member separate from the action member, and is integrated with the action member, the rubber valve body film, and the movable rubber film. It may be provided. For example, a protrusion protruding downward is integrally formed on the action member, and the protrusion is pressed against the rubber valve body film from the pressure receiving chamber side, thereby forming the pressing protrusion with the protrusion. You can also The pressing protrusion does not need to be formed of a rubber elastic body, and may be formed of metal, synthetic resin, or the like. Furthermore, the pressing protrusion does not necessarily have to be formed continuously over the entire circumference, and may be provided intermittently in a part or a plurality of locations in the circumferential direction.

  In the first and second embodiments, the structure including only the orifice passage tuned in the low frequency range is shown. For example, the first orifice passage tuned in the frequency range different from each other is shown. The present invention can also be applied to a so-called double-orifice fluid-filled vibration isolator having a second orifice passage. In addition, the specific description regarding tuning of the orifice channel | path 76 and the hydraulic pressure absorption part 116 in each said embodiment is an illustration to the last.

  In the first and second embodiments, a structure in which the present invention is applied to a so-called bowl-shaped fluid-filled vibration isolator is illustrated, but the inner cylinder member and the outer cylinder member are radially arranged. The present invention can also be applied to a so-called cylindrical fluid-filled vibration isolator having a structure connected by a main rubber elastic body.

  In the first and second embodiments, an automobile engine mount is shown as an example of the fluid filled type vibration damping device according to the present invention. However, the present invention is not necessarily applied only to the engine mount. For example, the present invention can be applied to various fluid-filled vibration damping devices such as an upper support in a suspension mechanism. Furthermore, the present invention is not limited to a fluid-filled vibration isolator for automobiles, and is used for a fluid-filled vibration isolator for other vehicles such as trains and vibrations other than vehicles. The present invention can also be applied to a fluid-filled vibration isolator.

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

It is sectional drawing which shows the engine mount for motor vehicles as 1st embodiment of this invention, Comprising: It is II sectional drawing in FIG. The top view of the partition member which comprises the same engine mount. The bottom view of the partition member. IV-IV sectional drawing in FIG. 5 of the movable rubber valve body which comprises the same engine mount. The top view of the movable rubber valve body. The expanded sectional view which shows the obstruction | occlusion state of the slit in the engine mount. The expanded sectional view which shows the opening state of the slit in the engine mount. It is sectional drawing which shows the engine mount for motor vehicles as 2nd embodiment of this invention, Comprising: VIII-VIII sectional drawing in FIG. The top view of the partition member which comprises the same engine mount. The bottom view of the partition member. XI-XI sectional drawing in FIG. 12 of the movable rubber valve body which comprises the same engine mount. The top view of the movable rubber valve body. The expanded sectional view which shows the obstruction | occlusion state of the slit in the engine mount. The expanded sectional view which shows the opening state of the slit in the engine mount. The expanded sectional view which shows the obstruction | occlusion state of the slit in the engine mount as another one Embodiment of this invention. The expanded sectional view which shows the opening state of the slit in the engine mount. The top view of the movable rubber valve body which comprises the engine mount as another one Embodiment of this invention. The expanded sectional view which shows the principal part of the engine mount as another one Embodiment of this invention.

Explanation of symbols

10: Automotive engine mount, 12: First mounting bracket, 14: Second mounting bracket, 16: Rubber elastic body, 26: Diaphragm, 34: Upper partition bracket, 42: Bulkhead, 68: Inner taper Surface: 70: insertion window, 72: pressure receiving chamber, 74: equilibrium chamber, 76: orifice passage, 78: movable rubber valve body, 84: slit, 82: valve body protrusion, 86: crack prevention hole, 88: base, 90: valve portion, 92: outer peripheral tapered surface, 114: movable rubber film, 128: annular pressing rubber

Claims (9)

The first mounting member and the second mounting member are connected by a main rubber elastic body, and a pressure receiving chamber in which a part of a wall portion is configured by the main rubber elastic body and incompressible fluid is enclosed, and a flexible In a fluid-filled vibration isolator in which a part of the wall portion is formed of a conductive film to form an equilibrium chamber in which an incompressible fluid is enclosed, and the pressure receiving chamber and the equilibrium chamber communicate with each other by an orifice passage.
A rubber valve body membrane is disposed between the pressure receiving chamber and the equilibrium chamber so that the pressure of the pressure receiving chamber is applied to one surface of the rubber valve body membrane and the equilibrium is applied to the other surface of the rubber valve body membrane. While the pressure of the chamber is exerted, while the rubber valve body film is formed with a longitudinal short-circuit opening extending with a predetermined opening width, both side edges sandwiching the short-circuit opening in the opening width direction are respectively provided. An action protrusion projecting toward the pressure acting surface side of the pressure receiving chamber is formed, and the pressure acting surface side of the pressure receiving chamber with respect to the rubber valve body film corresponds to the action protrusion of the rubber valve body film. An action member having an insertion window is disposed at a position and supported by the second mounting member, and the action protrusion of the rubber valve body film is inserted into the insertion window of the action member to insert the action member. The inner surface of the insertion window of the action member and the outer surface of the action protrusion of the rubber valve body membrane At least one of the abutting portions is inclined toward the base side of the working projection in the width direction so as to gradually narrow toward each other, and the working projection is displaced to the projecting side in the insertion window. In this state, the shunt is opened to allow the pressure receiving chamber and the equilibrium chamber to communicate with each other, while the working protrusion is displaced to the drawing side which is the base side in the insertion window. The short-circuit opening is closed by a guide action by a surface, and an urging mechanism is provided to urge the action protrusion toward the drawing side and elastically hold it at the position on the drawing side. A fluid-filled vibration isolator characterized by the above.   The fluid-filled type vibration damping device according to claim 1, wherein the short-circuit port has a shape extending linearly.   The fluid-filled vibration isolator according to claim 2, wherein the linearly extending short-circuit port is constituted by a plurality of linear portions extending so as to intersect each other.   The working protrusion in the rubber valve body membrane has a circular outer peripheral surface shape, and the plurality of straight portions constituting the short-circuit port intersect on the central axis of the working protrusion and the center The fluid filled type vibration damping device according to claim 3, wherein the vibration filled type vibration damping device is formed so as to extend in a direction orthogonal to the axis.   An inner surface of the insertion window in the action member is the inclined surface having a convex curved cross-sectional shape, and an outer surface of the action protrusion is the inclined surface having a linear cross-sectional shape, and the action protrusion 5. The contact position of these inclined surfaces is moved outward in the opening width direction of the short-circuit opening as the guide plate is displaced to the projecting side in the insertion window. 6. Fluid-filled vibration isolator.   The fluid-filled type according to any one of claims 1 to 5, wherein each tip end portion of the short-circuit port is formed with an end through hole having an opening width wide and a smooth curved inner peripheral surface. Anti-vibration device.   A movable rubber film is disposed between the pressure receiving chamber and the equilibrium chamber so that the pressure of the pressure receiving chamber is exerted on one surface of the movable rubber film, and the other surface of the movable rubber film is A hydraulic pressure absorbing mechanism that absorbs pressure fluctuations in the pressure receiving chamber by applying the pressure in the equilibrium chamber constitutes the short circuit port and the action bump against the movable rubber film of the hydraulic pressure absorbing mechanism. The fluid-filled vibration isolator according to claim 1, wherein the rubber valve body film is formed by forming a portion.   A pressing force in a direction of pressing the pressure acting surface side of the pressure receiving chamber is exerted by the acting member on the outer peripheral portion of the working projecting portion of the rubber valve body film, so that the acting projecting portion is directed toward the drawing side. The fluid filled type vibration damping device according to any one of claims 1 to 7, wherein the biasing mechanism is configured to be biased and elastically held at a position on the drawing side.   A pressing protrusion protruding from at least one of the opposing surfaces of the rubber valve body film and the action member toward the other is provided at an outer peripheral portion of the action protrusion in the rubber valve body film, and the pressing protrusion The fluid filled type vibration damping device according to claim 8, wherein the biasing mechanism is configured by exerting a pressing force on the rubber valve body film.

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