JP2010249288A - Vibration control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To surely switch restriction passages, and to simplify a structure in a vibration control device switching a plurality of the restriction passages in accordance with an input vibration frequency band. <P>SOLUTION: A third restriction passage 35 is formed between a peripheral groove 33 almost encircling an outer periphery of a partition member 30 and a lower film 18. A first restriction passage 36 is configured to pass through the partition member 30 along an axial direction S. A second restriction passage 40 is configured to pass through the partition member 30 along the axial direction S at a corresponding position while fastening the first restriction passage 36 of the partition member 30. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a vibration isolator that is used as an engine mount or the like in a general industrial machine or an automobile and absorbs and attenuates vibration transmitted from a vibration generating unit such as an engine to a vibration receiving unit such as a vehicle body.

  An anti-vibration device as an engine mount is disposed between the engine that is the vibration generation unit of the vehicle and the vehicle body that is the vibration receiving unit. As the anti-vibration device, the main component that expands and contracts according to the deformation of the rubber elastic body. A liquid-enclosed engine mount is disclosed that includes a liquid chamber and a sub-liquid chamber connected to the main liquid chamber by a restriction passage (orifice). In the liquid-sealed engine mount, a vibration isolating effect is obtained by utilizing the liquid column resonance of the liquid moving in the restricted passage.

By the way, in order to obtain an effective anti-vibration effect with respect to input vibrations in a wider frequency band as such a liquid-filled engine mount, a plurality of restricted passages tuned to different frequency bands are connected to the input vibration frequency. Switching is used according to the band.

For example, in Patent Document 1, opening and closing of a restriction passage tuned for high frequency is switched according to the frequency of input vibration, and closing is performed with a movable film. In Patent Document 2, three restriction passages corresponding to three different frequency bands, a low frequency band, a medium frequency band, and a high frequency band, are provided, and a movable film is disposed in the restriction passage corresponding to the high frequency band. Thus, the restriction passage for the medium frequency band and the restriction passage for the high frequency band are switched so as to be alternatively communicated.

However, in Patent Document 1, since locking and opening of the movable film is not forcibly performed on the apparatus side, there is a case where the restriction passage for the high frequency band is not effectively closed. Further, in Patent Document 2, the restriction passage for the medium frequency band and the restriction passage for the high frequency band share the valve body in the partition member, and the restriction passage in the partition member has a complicated shape. And tuning is difficult.

JP 2008-121811 A JP-A-11-230242

  The present invention has been made in consideration of the above facts, and in a vibration isolator that switches a plurality of restricted passages in accordance with an input vibration frequency band, the restricted passage can be switched reliably and a simpler configuration can be achieved. An object is to provide a vibration isolator.

  The vibration isolator according to claim 1 is an attachment member connected to one of the vibration generator and the vibration receiver, a cylindrical outer cylinder connected to the other of the vibration generator and the vibration receiver, and the attachment An elastic body that connects a member and the outer cylinder, deforms by vibration input from a vibration generating unit, and a liquid is sealed, and a part of the partition wall is formed by the elastic body and expands and contracts by deformation of the elastic body. A liquid chamber, a liquid is sealed, a part of the partition wall is formed of a diaphragm, and the main liquid chamber and the sub liquid chamber are partitioned by dividing the main liquid chamber and the sub liquid chamber, and the main liquid chamber is expanded and contracted by a change in liquid pressure. A partition member in which a first restriction passage, a second restriction passage, and a third restriction passage for communicating the liquid chamber and the sub liquid chamber are separately configured, and the main liquid so as to close the first restriction passage A movable elastic membrane that is elastically deformable, disposed on the chamber side, the first restriction passage, and the A first position for communicating with the liquid chamber and closing the second restriction passage; and a second position for disabling the first restriction passage and the secondary liquid chamber and opening the second restriction passage. A switching member movable between the actuator and an actuator for moving the switching member between the first position and the second position.

  In the vibration isolator according to claim 1, when the switching member is disposed at the first position, the third restriction passage and the auxiliary liquid chamber, and the first restriction passage and the auxiliary liquid chamber are communicated with each other, The second restriction passage is closed. Therefore, it is possible to effectively obtain a vibration isolation effect for vibration corresponding to tuning of the third restriction passage and vibration corresponding to tuning of the first restriction passage.

  Moreover, when the switching member is arrange | positioned in the 2nd position, a 1st restriction | limiting channel | path and a subliquid chamber are disconnected, and the 2nd restriction | limiting channel | path is open | released. Therefore, it is possible to effectively obtain a vibration isolation effect for the vibration corresponding to the tuning of the third restriction passage and the vibration corresponding to the second restriction passage.

  In the present invention, the switching between the first restriction passage and the second restriction passage can be reliably performed by the movement of the switching member by the actuator. Moreover, since the 1st-3rd restriction | limiting path | route is each comprised by the partition member separately, while being able to be made a simple structure, each tuning can be performed easily.

  According to a second aspect of the present invention, the switching member is inserted into the first restriction passage and moves along the first restriction passage to open and close the opening of the first restriction passage to the sub liquid chamber. A first switching unit; and a second switching unit configured integrally with the first switching unit to open and close the opening of the second restriction passage to the sub liquid chamber. .

  With the above configuration, the switching member can be moved using the first restriction passage, and a simple configuration can be realized.

  The invention described in claim 3 is characterized in that the first restriction passage is configured to penetrate through a central portion of the partition member.

  Thus, by arranging the first restricting passage in the center of the partition member, the first restricting passage can be made simple and the characteristics of the movable elastic membrane can be effectively exhibited.

  The invention according to claim 4 is characterized in that the diaphragm forms a seal surface at a position facing the opening of the second restriction passage of the second switching portion by being bonded to the second switching portion. To do.

Thus, by closing the second restriction passage using a part of the diaphragm, it is not necessary to prepare another member and a simple configuration can be achieved.

The invention according to claim 5 is characterized in that the actuator moves the switching member by switching a chamber chamber formed on the opposite side of the main liquid chamber of the switching member between a negative pressure and an atmospheric pressure. It is characterized by.

Thus, the switching member can be moved using the pressure switching type actuator.

  As described above, according to the above-described configuration of the present invention, in the vibration isolator that switches a plurality of restricted passages according to the input vibration frequency band, the restricted passage is reliably switched, and the vibration proof having a simpler configuration is provided. It can be a device.

It is a sectional side view which shows the structure (at the time of idle mode) of the vibration isolator which concerns on embodiment of this invention. It is a sectional side view which shows the structure (at the time of a shake mode) of the vibration isolator which concerns on embodiment of this invention. It is the sectional side view rotated 90 degree | times from the state of FIG. 1 which shows the structure (in idle mode) of the vibration isolator which concerns on embodiment of this invention. It is the sectional side view rotated 90 degree | times from the state of FIG. 2 which shows the structure (at the time of a shake mode) of the vibration isolator which concerns on embodiment of this invention. It is a disassembled perspective view which shows the structure of the partition member vicinity of the vibration isolator which concerns on embodiment of this invention. It is the graph which showed the vibration proof characteristic.

  Hereinafter, an embodiment of a vibration isolator according to the present invention will be described with reference to the drawings.

  1 to 4 show a vibration isolator 10 according to an embodiment of the present invention. The vibration isolator 10 is applied as an engine mount that supports an engine that is a vibration generating unit in an automobile to a vehicle body that is a vibration receiving unit. Note that the symbol S in the figure indicates the axis of the apparatus, the direction along the axis is the axis direction S of the apparatus, and the vertical direction in the figure is the vertical direction of the vibration isolator 10 in the following description. Main vibration (main vibration) for the purpose of vibration isolation is input in the axial direction S.

  As shown in FIGS. 1 to 4, the vibration isolator 10 includes an attachment member 12 attached to the engine side, an outer cylinder 20 attached to the vehicle body side, and a rubber elastic body connecting the attachment member 12 and the outer cylinder 20. With 16

The outer cylinder 20 includes a substantially cylindrical cylindrical portion 20A, a flange portion 20B extending radially outward from one end of the cylindrical portion 20A, a partition member 30 and a diaphragm 44 described later on the other end side of the cylindrical portion 20A, and the like. It has a caulking portion 20C for caulking and fixing. The caulking portion 20C extends radially outward from the other end side of the cylindrical portion 20A, and the tip end portion thereof is bent and crimped to the opposite side of the flange portion 20B.

The mounting member 12 has a substantially conical shape whose outer diameter is smaller than the inner diameter of the outer cylinder 20, is coaxial with the outer cylinder 20, protrudes outside the outer cylinder 20 in the axial direction S, and has a smaller diameter side on the outer cylinder It arrange | positions so that it may become 20 side. A recess 12 </ b> A is formed at the tip of the mounting member 12 on the outer cylinder 20 side. A connecting portion 12 </ b> C is formed on the end surface 12 </ b> B on the large diameter side of the mounting member 12. The attachment member 12 is connected to an engine (not shown) by an attachment portion (not shown).

  The rubber elastic body 16 is vulcanized and bonded to the outer periphery of the mounting member 12 and is vulcanized and bonded to the inner periphery of the cylindrical portion 20A of the outer cylinder 20 to elastically connect the mounting member 12 and the outer cylinder 20 to each other. is doing. A concave portion 16 </ b> A is formed on the lower surface of the rubber elastic body 16 (the surface on the outer cylinder 20 side). The rubber elastic body 16 is integrally formed with a thin lower film 18 extending toward the caulking portion 20 </ b> C along the inner wall of the outer cylinder 20. The inner surface of the outer cylinder 20 is covered with the lower film 18.

  A partition member 30 is fixed coaxially with the outer cylinder 20 on the caulking portion 20 </ b> C side inside the outer cylinder 20. A main liquid chamber 26 is formed between the partition member 30 and the rubber elastic body 16. The main liquid chamber 26 is fluid-tight and filled with liquid. As the liquid, water, ethylene glycol or the like can be used.

  As shown in FIG. 5, the partition member 30 has a substantially columnar shape, a small-diameter portion 32 is formed at an end portion on the main liquid chamber 26 side in the axial direction S, and a large-diameter portion 34 is formed at an intermediate portion in the axial direction S. Is formed. The small-diameter portion 32 has a flange shape slightly smaller in diameter than the cylindrical portion 20A, and is press-fitted through the lower film 18 to the inner periphery of the cylindrical portion 20A. The large-diameter portion 34 has a flange shape larger in diameter than the cylindrical portion 20A, and is clamped and fixed together with the lower film 18 and a later-described diaphragm 44 together with the caulking portion 20C. A passage portion 31 is formed at the center of the lower surface side of the large diameter portion 34 so as to protrude downward.

  A circumferential groove 33 is formed between the small diameter portion 32 and the large diameter portion 34 on the outer periphery of the partition member 30. The circumferential groove 33 is configured so as to make one round of the outer periphery of the partition member 30, and the circumferential groove 33 is closed by the inner circumferential surface (lower film 18) of the outer cylinder 20, thereby forming the third restriction passage 35. ing. One end side of the third restriction passage 35 communicates with the main liquid chamber 26, and the other end side communicates with a sub liquid chamber 28 described later. The length and cross-sectional area of the third restriction passage 35 are set (tuned) so as to match the frequency (for example, 8 to 15 Hz) and amplitude of the shake vibration.

  A first restriction passage 36 that penetrates the partition member 30 in the axial direction S is formed at the center of the partition member 30. A lid hole plate 38 and a movable elastic film 37 are disposed on the main liquid chamber 26 side of the first restriction passage 36. As shown in FIG. 5, the lid hole plate 38 has a disk shape, and a plurality of holes are perforated. The lid hole plate 38 is disposed closer to the main liquid chamber 26 than the movable elastic film 37.

  The movable elastic film 37 has a disk shape and can be elastically deformed. The movable elastic membrane 37 is spaced from the lid hole plate 38 below the lid hole plate 38 so as to close the first restriction passage 36. An intermediate hole 39 is formed below the movable elastic film 37. The intermediate hole 39 has a disk shape, and a plurality of holes are perforated. The intermediate hole 39 and the movable elastic film 37 are also spaced apart. Thereby, the movable elastic film 37 can be vibrated between the cover hole plate 38 and the intermediate hole portion 39 by elastic deformation.

  A side of the first restriction passage 36 opposite to the main liquid chamber 26 is constituted by a passage portion 31. A portion of the passage portion 31 corresponding to the first restriction passage 36 (hereinafter referred to as “center tube portion 31 </ b> A”) has a cylindrical shape, and the first restriction passage 36 is formed in the cylinder. Moreover, the opening 36A connected to the sub-liquid chamber 28 mentioned later is comprised by the side wall of 31 A of center cylinder parts at two opposing positions. The first restriction passage 36 has a length, a cross-sectional area, and the like so as to obtain an effective anti-vibration effect with respect to a high-frequency vibration of about 70 to 120 Hz (hereinafter referred to as “high-frequency vibration”).

  A second restriction passage 40 that penetrates the partition member 30 in the axial direction S is formed on both sides of the first restriction passage 36 of the partition member 30. A side of the second restriction passage 40 opposite to the main liquid chamber 26 is constituted by a passage portion 31. A portion of the passage portion 31 corresponding to the second restriction passage 40 (hereinafter referred to as a “side portion 31B”) extends radially outward from the central cylindrical portion 31A, and is configured integrally with the central cylindrical portion 31A. A through hole is formed so as to correspond to the restriction passage 40. The second restriction passage 40 has a length and a cross-sectional area so as to obtain an effective vibration-proofing effect against vibrations of about 15 to 40 Hz (hereinafter referred to as “idle vibrations”) having a lower frequency than high-frequency vibrations. Has been.

  A sub liquid chamber 28 is formed on the opposite side of the main liquid chamber 26 across the partition member 30. The auxiliary liquid chamber 28 is configured by being surrounded by a partition member 30, a diaphragm 44, and a slide valve 50. The secondary liquid chamber 28 is fluid-tight and filled with liquid. As the liquid, water, ethylene glycol or the like can be used. The sub-fluid chamber 28 is expanded and contracted so that the diaphragm 44 is deformed according to the fluid pressure and the fluid pressure change is suppressed.

  The slide valve 50 includes a first switching part 52, a second switching part 54, and an outer peripheral part 56. The first switching unit 52 has a bottomed cylindrical shape, and includes a cylindrical shaft portion 52A and a disc-shaped bottom plate portion 52B. The outer diameter of the shaft portion 52 </ b> A is slightly smaller than the inner diameter of the first restriction passage 36. The bottom plate portion 52B closes one end side of the shaft portion 52A, and a convex portion 51 is formed on the outer surface side. The shaft portion 52A is inserted into the first restriction passage 36 from the side opposite to the bottom plate portion 52B. The shaft 52A has an opening 52H that overlaps with the opening 36A and forms the communication port 36H in a state where the insertion tip side of the shaft 52A is close to the intermediate hole 39.

  The 2nd switching part 54 is made into the flange shape which extended the baseplate part 52B of the 1st switching part 52 to the radial direction outer side. An inner end portion of a diaphragm 44 described later is bonded to the upper surface side (side facing the partition member 30) of the second switching portion 54, thereby forming a seal portion 44A. When the shaft portion 52A is disposed at a position where the opening 36A and the opening 52H overlap to form the communication port 36H (hereinafter referred to as “shake position P2”), the second switching portion 54 has the seal portion 44A disposed in the passage portion 31. And the second restriction passage 40 is closed. The shaft portion 52A moves below the shake position P2, the opening 36A is closed by the outer wall of the shaft portion 52A, the opening 52H is closed by the inner wall of the central cylindrical portion 31, and the seal portion 44A is lowered from the passage portion 31. Hereinafter, a position where the second restriction passage 40 is opened away to the side is referred to as an idle position P1. The slide valve 50 is movable in the axial direction S, and is moved between a shake position P2 and an idle position P1 by an actuator 60 described later.

  The outer peripheral portion 56 has a cylindrical shape arranged coaxially with the shaft portion 52 </ b> A, and is configured to extend downward from the outer peripheral end of the second switching portion 54. A movable diaphragm 62 to be described later is bonded to the outer peripheral portion 56.

  The diaphragm 44 is composed of a thin film and has a substantially annular shape. The outer peripheral end of the diaphragm 44 is caulked together with the lower film 18, the large diameter portion 34, and an upper end portion 58A of a bracket 58 described later. On the upper and lower surfaces of the inner diameter side slightly from the outer periphery of the diaphragm 44, annular seal ridges 45A and 45B are respectively configured. The seal ridge 45A is inserted into a groove 34A formed on the lower surface of the large-diameter portion 34, and the seal ridge 44B is inserted into a groove 59A of an intermediate cylinder 59 described later. The inner peripheral end of the diaphragm 44 is bonded to the upper surface of the second switching portion 54 to form a seal portion 44A. Bonding of the diaphragm 44 to the second switching portion 54 can be performed by vulcanization.

  A bracket 58 is disposed below the outer cylinder 20. The bracket 58 has a substantially cylindrical shape, and the upper end 58A is curved outward in the radial direction. On the upper end portion 58, the outer peripheral end of the diaphragm 44, the outer peripheral end of the large diameter portion 34, and the lower end portion of the lower film 18 are laminated and fixed by caulking from the outside by a caulking portion 20C.

  An actuator 60 is disposed below the slide valve 50 and inside the bracket 58. The actuator 60 includes an intermediate cylinder 59, a movable diaphragm 62, a bottom plate member 64, a coil spring 63, and a pressure switching unit 66.

  The intermediate cylinder 59 is disposed on the inner peripheral side of the bracket 58. The intermediate cylinder 59 has a cylindrical shape and has an outer diameter slightly smaller than the inner diameter of the bracket 58. On the upper end surface and the lower end surface of the intermediate tube 59, groove portions 59A and 59B, which are grooves that make one round in the circumferential direction, are configured. Further, a through hole 59C is drilled in the side wall of the intermediate cylinder 59, and a recess 59D that is recessed radially inward from the other outer peripheral surface is formed below the outer peripheral surface corresponding to the through hole 59C. . The through hole 59C and the recess 59D constitute an atmosphere communication path 58E that communicates the inside of the intermediate cylinder 59 and the atmosphere outside the bracket 58.

The movable diaphragm 62 is formed of a thin film and has a substantially annular shape. The inner peripheral end of the movable diaphragm 62 is bonded to the outer peripheral portion of the slide valve 50. On the upper and lower surfaces of the inner diameter side slightly from the outer periphery of the movable diaphragm 62, annular seal protrusions 62A and 62B are respectively configured. The seal protrusion 62A is inserted into the groove 59A of the intermediate tube 59. The seal protrusion 62B is inserted into a groove portion 64A described later of the bottom plate member 64.
The bonding of the movable diaphragm 62 and the diaphragm 44 to the slide valve 50 can be performed in one step by vulcanization.

  The bottom plate member 64 has a substantially disk shape and is press-fitted and fixed inside the bracket 58. In the actuator 60, the bottom plate member 64, the movable diaphragm 62, and the outer peripheral portion 56 of the slide valve 50 constitute a chamber chamber 67 surrounded by them. A switching port 65 that protrudes toward the partition member 30 is formed at the center of the bottom plate member 64. The chamber chamber 67 and the pressure switching unit 66 are communicated with each other via the switching port 65.

  A pressure switching unit 66 is connected to the switching port 65. The pressure switching unit 66 includes an atmospheric pressure space 66A, a negative pressure space 66B, and a switching valve 66C. When the switching valve 66C is switched to the atmospheric pressure space 66A, the chamber chamber 67 communicates with the atmospheric pressure space 66A, and the inside of the chamber chamber 67 is at atmospheric pressure. When the switching valve 66C is switched to the negative pressure space 66B, the chamber chamber 67 communicates with the negative pressure space 66B, and the inside of the chamber chamber 67 becomes negative pressure.

  A controller 66D is connected to the switching valve 66C, and a vehicle speed sensor 66E and an engine speed sensor 66F are connected to the controller 66D. The controller 66D determines the driving situation of the vehicle and transmits a switching signal to the switching valve 66C. The controller 66D is connected to a vehicle speed sensor 66E that determines the driving state of the vehicle and an engine speed sensor 66F that detects the engine speed path. Based on the signals from the vehicle speed sensor 66E and the engine speed sensor 66F, the controller 66D determines whether shake vibration or idle vibration occurs, that is, whether the vehicle is stopped or running.

  A coil spring 63 is disposed below the shaft portion 52A of the slide valve 50. One end of the coil spring 63 is extrapolated to the convex portion 51, and the other end is extrapolated to the switching port 65. The slide valve 50 is supported by the coil spring 63.

  When the chamber 67 is communicated with the atmospheric pressure space 66A and is at atmospheric pressure, the slide valve 50 is disposed at the shake position P2 by the urging force of the coil spring 63. The state of the vibration isolator 10 at this time is hereinafter referred to as “shake mode”. When the chamber chamber 67 communicates with the negative pressure space 66B and is at a negative pressure, the slide valve 50 moves downward against the biasing force of the coil spring 63 by the suction from the chamber chamber 63, and the idle position P1. Placed in. The state of the vibration isolator 10 at this time is hereinafter referred to as “idle mode”.

  FIG. 6 shows an example of the characteristics of the vibration isolator 10. FIG. 6A shows the relationship between the absolute spring constant of the vibration isolator 10 and the input vibration frequency when the amplitude is 0.1 mm in the idle mode. The absolute spring constant is suppressed in the idle region of 15 to 40 Hz. FIG. 6B shows the relationship between the absolute spring constant of the vibration isolator 10 and the input vibration frequency when the amplitude is 0.1 mm in the shake mode. In the high frequency region of 70 to 120 Hz, the absolute spring constant is suppressed. FIG. 6C shows the relationship between the damping coefficient of the vibration isolator 10 and the input vibration frequency when the amplitude is 1.0 mm in the shake mode. High attenuation can be obtained in a low frequency region of 8 to 15 Hz.

  Next, the operation and action of the vibration isolator 10 according to the present embodiment configured as described above will be described.

  When the engine to which the attachment member 12 is connected operates, the vibration of the engine is transmitted to the rubber elastic body 16 via the attachment member 12. The rubber elastic body 16 acts as a vibration absorbing main body and can absorb vibrations by a vibration absorbing function based on elastic deformation of the rubber elastic body 16. Further, along with the deformation of the rubber elastic body 16, the internal volume of the main liquid chamber 26 changes (expands / contracts) to change the hydraulic pressure, and according to the amplitude and frequency of the input vibration and the position of the slide valve 50. Thus, the liquid flows between the main liquid chamber 26 and the sub liquid chamber 28 through the first restriction passage 36, the second restriction passage 40, and the third restriction passage 35. Note that the first restriction passage 36 moves in accordance with the vibration caused by the elastic deformation of the movable elastic film 37. In the sub liquid chamber 28, the diaphragm 44 is deformed with a small resistance as the liquid flows in and out, so that the liquid pressure change is sufficiently small with respect to the liquid pressure change in the main liquid chamber 26.

  As a result, in the vibration isolator 10, when vibration from the engine side is transmitted through the attachment member 12, the vibration isolator 10 is not only damped by the deformation of the rubber elastic body 16 but also the main liquid chamber 26 and the sub liquid chamber 28. The vibration is attenuated by the damping action based on the liquid column resonance or the like in the restriction passages communicating with each other, and the vibration is hardly transmitted to the vehicle body side.

  Below, operation | movement and an effect | action of the vibration isolator 10 which concern on this Embodiment are demonstrated more concretely.

  Controller 66D switches switching valve 66C to the atmospheric pressure space 66A side when it is determined that shake vibration is occurring based on signals from vehicle speed sensor 66E and engine speed sensor 66F. Accordingly, the chamber chamber 67 becomes atmospheric pressure, and the slide valve 50 is disposed at the shake position P2 by the reaction force of the coil spring 63, as shown in FIGS. Thus, the opening 36A of the first restriction passage 36 overlaps with the opening 52H of the shaft portion 52A to form a communication hole 36H, and the first restriction passage 36 communicates with the sub liquid chamber 28. The second restriction passage 40 is closed by the seal portion 44A of the second switching portion 54.

  In this state, when shake vibration is input, a resonance phenomenon (liquid column resonance) occurs in the liquid that flows between the main liquid chamber 26 and the sub liquid chamber 28 through the third restriction passage 35, As shown in FIG. 6C, a high damping effect can be obtained during shake vibration.

  Further, the vehicle travels at a speed higher than the speed at which the shake vibration is generated, and the vibration transmitted to the vibration isolator 10 is a high-frequency vibration having a frequency higher than that of the idle vibration, and a high-frequency such as a booming sound having a small amplitude. When the vibration is generated, in the vibration isolator 10, the third restriction passage 35 tuned to match the shake vibration becomes clogged, and the liquid does not easily flow through the third restriction passage 35. On the other hand, the movable elastic film 37 is elastically deformed so as to expand and contract the internal volume of the main liquid chamber 26 in response to the input vibration, so that an increase in the hydraulic pressure in the main liquid chamber 26 can be suppressed. As shown in FIG. 6B, it is possible to suppress an increase in the dynamic spring constant of the device (rubber elastic body 16) due to the increase in the hydraulic pressure in the main liquid chamber 26. Accordingly, even when such high-frequency vibrations such as a booming sound are input, the absolute spring constant of the rubber elastic body 16 can be kept low and high-frequency vibrations can be effectively absorbed.

  On the other hand, the controller 66D switches the switching valve 66C to the negative pressure space 66B side when it is determined that idle vibration is occurring based on signals from the vehicle speed sensor 66E and the engine speed sensor 66F. Thereby, the chamber chamber 67 becomes negative pressure, and as shown in FIGS. 1 and 3, the slide valve 50 is disposed at the idle position P1. As a result, the opening 36A of the first restriction passage 36 is closed by the shaft portion 52A, and the movement of the liquid between the main liquid chamber 26 and the sub liquid chamber 28 via the first restriction passage 36 becomes impossible. The movable elastic film 37 is in a locked state (a state where it is not elastically deformed). On the other hand, the second restriction passage 40 is opened when the second switching portion 54 moves downward and the seal portion 44A is separated.

  In this state, when the idle vibration is input, the third restriction passage 35 tuned to match the shake vibration is clogged, but the second restriction passage 40 is opened, so the third restriction passage 35 is opened. The liquid comes and goes between the main liquid chamber 26 and the sub liquid chamber 28 through the second restriction passage 40 having a smaller flow resistance of the liquid than the passage 35. At this time, a resonance phenomenon (liquid column resonance) occurs in the liquid that flows between the main liquid chamber 26 and the sub liquid chamber 28 through the second restriction passage 40, and as shown in FIG. It is possible to effectively absorb the idle vibration by keeping the absolute spring constant low when the idle vibration is input.

  Further, in the vibration isolator 10, when the idle vibration is generated, the movable elastic film 37 is locked and the main liquid chamber 26 is prevented from elastic deformation in the volume expansion / contraction direction. It is possible to prevent the movable elastic film 37 from being deformed in the volume expansion / contraction direction due to the fluid pressure change in the fluid 26 and the fluid pressure change in the main fluid chamber 26 being suppressed. Accordingly, it is possible to reliably prevent the driving force (pumping force) that causes the liquid to flow through the second restriction passage 40 due to the elastic deformation of the movable elastic film 37.

  As described above, in the vibration isolator 10 according to the present embodiment, the vibration isolating effect can be exerted more effectively by switching between the shake mode and the idle mode according to the input vibration.

  In addition, the first restriction passage 36, the second restriction passage 40, and the third restriction passage 35 are each configured separately in the partition member 30, and the above switching can be realized with a simple structure. Can be easily tuned.

  In the vibration isolator 10 according to the present embodiment, the example in which the pressure switching type actuator is used as the actuator has been described. However, another type of actuator, for example, an electromagnetic actuator may be used.

DESCRIPTION OF SYMBOLS 10 Vibration isolator 12 Attachment member 16 Rubber elastic body 20 Outer cylinder 26 Main liquid chamber 28 Sub liquid chamber 30 Partition member 35 1st restriction path 36 2nd restriction path 37 Movable elastic film 38 Cover hole board 39 Middle hole part 40 Restriction path 44A Sealing portion 44 Diaphragm 50 Slide valve 60 Actuator P2 Shake position P1 Idle position S Axial direction

Claims (5)

An attachment member connected to one of the vibration generating portion and the vibration receiving portion;
A cylindrical outer cylinder connected to the other of the vibration generating part and the vibration receiving part;
An elastic body that connects the mounting member and the outer cylinder, and is deformed by vibration input from a vibration generating unit;
A main liquid chamber in which a liquid is enclosed, a part of a partition wall is constituted by the elastic body, and expands and contracts by deformation of the elastic body;
A sub liquid chamber in which a liquid is enclosed, a part of the partition wall is configured by a diaphragm, and the internal volume is expanded and contracted by a change in hydraulic pressure;
A partition in which the first restriction passage, the second restriction passage, and the third restriction passage that separate the main liquid chamber and the sub liquid chamber and communicate the main liquid chamber and the sub liquid chamber are configured separately. Members,
A movable elastic membrane that is elastically deformable and disposed on the main liquid chamber side so as to close the first restriction passage;
The first restriction passage communicates with the secondary liquid chamber and closes the second restriction passage, the first restriction passage and the secondary liquid chamber are made non-communication and the second restriction passage is opened. A switching member movable between the second position to be opened; and
An actuator for moving the switching member between the first position and the second position;
Anti-vibration device with   The switching member is inserted into the first restriction passage, moves along the first restriction passage, and opens and closes the opening of the first restriction passage to the sub liquid chamber; 2. A vibration isolator according to claim 1, further comprising: a second switching unit configured integrally with the switching unit to open and close an opening of the second restriction passage to the sub liquid chamber. .   3. The vibration isolator according to claim 1, wherein the first restriction passage is configured to penetrate a central portion of the partition member.   The said diaphragm is adhere | attached on the said 2nd switching part, and comprises a sealing surface in the position facing the opening of the said 2nd restriction | limiting channel | path of the said 2nd switching part, The Claim 2 or Claim 3 characterized by the above-mentioned. The vibration isolator as described.   The said actuator moves the said switching member by switching the chamber chamber comprised on the opposite side to the said main liquid chamber of the said switching member to a negative pressure and atmospheric pressure. Item 5. The vibration isolator according to any one of items 4.

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