JP5468513B2 - Liquid-filled vibration isolator - Google Patents

Description

  The present invention relates to a liquid-filled vibration isolator.

  As an anti-vibration device such as an engine mount that supports the vibration of a vibration source such as an automobile engine so as not to be transmitted to the vehicle body side, a first attachment attached to the vibration source side, a second attachment attached to the support side, An anti-vibration base made of a rubber-like elastic body interposed between the fixtures, a main liquid chamber in which the anti-vibration base forms part of the chamber wall, and a sub-liquid chamber in which the diaphragm forms part of the chamber wall; A liquid-filled vibration isolator having an orifice channel for communicating between these liquid chambers is known. The liquid-filled vibration isolator is configured to perform a vibration damping function and a vibration insulating function by a liquid column resonance action caused by a liquid flow in the orifice channel and a vibration damping effect of the vibration isolation substrate.

  As this type of liquid-filled vibration isolator, in Patent Document 1 below, as shown in a schematic diagram of FIG. 9, a first fixture and a second fixture are connected by a vibration isolator base 100, and the vibration isolator is shown. A main liquid chamber 101 in which the base body 100 forms a part of the chamber wall, a first sub-liquid chamber 103 in which the first diaphragm 102 forms a part of the chamber wall, and a second diaphragm 104 having a larger expansion elasticity than the first diaphragm 102. A second sub-liquid chamber 105 separated from the first sub-liquid chamber 103 by the second sub-liquid chamber 105 and the second sub-liquid chamber 105 by the first orifice channel 106. The first sub-liquid chamber 103 is communicated with the second orifice channel 107, and the main liquid chamber 101 and the second sub-liquid chamber 105 are connected by the combined equivalent mass of the first orifice channel 106 and the second orifice channel 107. The third orifice channel 108 having a small equivalent mass With communicating, to the third orifice passage 108, which provided a flow regulating valve 109 for regulating the flow of the liquid inside the on input of a predetermined amplitude or more vibration is disclosed.

  This liquid-sealed anti-vibration device is equipped with a valve (movable rubber) that moves according to the differential pressure and regulates the flow of liquid to achieve characteristics against engine shake, idle vibration, booming noise, and acceleration noise. be able to. More specifically, for a large amplitude vibration such as an engine shake, the flow restricting valve 109 closes the third orifice channel 108, thereby causing a resonance effect of the liquid flowing through the first orifice channel 106. Demonstrate the damping effect. In addition, for a small amplitude vibration of 20 to 40 Hz such as idle vibration, the flow restricting valve 109 opens the third orifice flow path 108, so that the liquid is added to the first orifice flow path 106 and the third The orifice flow path 108 and the second orifice flow path 107 also flow, whereby the input vibration is resonant due to the combined equivalent mass of the first orifice flow path 106 and the second orifice flow path 107 and the expansion elasticity of the first diaphragm 102. Is reduced. Further, for a small amplitude vibration in a high frequency range such as a booming noise or an acceleration noise, a reduction effect is exhibited by the resonance action of the liquid flowing through the third orifice channel 108.

Japanese Patent Laid-Open No. 10-122294

  In the above prior art, the idle vibration is dealt with by one resonance system including two orifice channels, ie, the first orifice channel and the second orifice channel. As shown by C ′ in FIG. For the attenuation coefficient in the low frequency range, only a characteristic having one peak can be obtained.

  The present invention has been made in view of the above points, and satisfies an anti-vibration performance against a large amplitude vibration such as an engine shake and a vibration of a small amplitude high frequency region such as a booming sound, and is similar to an idle vibration. To provide a liquid-filled vibration isolator capable of satisfying the vibration isolating requirements for idling vibration at a higher level by realizing a characteristic having two peaks for vibration attenuation in a very low amplitude low frequency range Objective.

  The liquid-filled vibration isolator according to the present invention includes a first fixture that is attached to one of the vibration source side and the support side, a second fixture that is attached to the other of the vibration source side and the support side, and the first attachment. An anti-vibration base made of a rubber-like elastic body interposed between the fixture and the second fixture, a main liquid chamber in which a liquid forming a part of a chamber wall of the anti-vibration base is enclosed, and rubber-like elasticity A first sub-liquid chamber in which a liquid in which a first diaphragm made of a membrane forms a part of a chamber wall is sealed and a second diaphragm made of a rubber-like elastic film is partitioned from the first sub-liquid chamber to enclose the liquid. A second sub-liquid chamber, a third sub-liquid chamber that is partitioned from the first sub-liquid chamber by a third diaphragm made of a rubber-like elastic film, and in which liquid is enclosed, the main liquid chamber, and the first sub-liquid A first orifice channel for communicating the chamber, and a tuning frequency higher than that of the first orifice channel And the second sub-liquid chamber and the third sub-liquid chamber communicating with each other, and the main liquid chamber and the second sub-liquid are tuned to a higher frequency region than the second orifice channel. A third orifice channel for communicating the chamber; a switching valve provided in the third orifice channel for opening and closing the third orifice channel; and an open state for opening the third orifice channel; And a switching valve that switches to a closed state that closes the third orifice channel when a vibration having a larger amplitude than that in the open state is input.

In the first aspect of the present invention, the liquid-filled vibration isolator is configured such that the first orifice channel of the first, second, and third orifice channels is closed by closing the third orifice channel by the switching valve. The first state where the liquid flow occurs only in the orifice flow path, and the liquid flow occurs in the first, second and third orifice flow paths when the third orifice flow path is opened by the switching valve. The first orifice channel and the second orifice channel are clogged by the vibration input in the second state and in a higher frequency range than the second state, and the liquid is only in the third orifice channel. to have a third state in which the flow of the results.

According to a fourth aspect of the present invention, the second fixture has a cylindrical shape, and the first diaphragm is attached to the second fixture to form a liquid chamber in which liquid is sealed between the anti-vibration base. The liquid chamber is partitioned into the main liquid chamber and the first sub liquid chamber by a partition portion fitted inside the peripheral wall portion of the second fixture, and the second liquid chamber is divided into the second portion. A sub liquid chamber, the third sub liquid chamber, the first orifice flow channel, the second orifice flow channel, the third orifice flow channel, and the switching valve are provided, and the switching valve has an outer peripheral portion at the partition portion. A valve body made of a rubber-like elastic membrane held in a liquid-tight manner is provided, and a pair of restricting plates for restricting deformation of the valve body are provided on both front and back sides of the valve body, and the third orifice flow is provided on the restricting plate. A communication hole forming a path is provided; A through hole is provided in a position that does not overlap with the communication hole in the main body, and the switching valve is configured to close the third orifice channel by closing the communication hole by bending deformation of the valve body. ing.

  According to the liquid-filled vibration isolator according to the present invention, for large amplitude vibration such as engine shake, the fluid that flows through the first orifice channel by the switching valve closing the third orifice channel. The damping effect is exhibited by the resonance action. For vibrations in a low amplitude region such as an idle vibration, the switching valve opens the third orifice channel, so that the resonance system by the first orifice channel and the first diaphragm, and the second orifice channel. And a characteristic having two attenuation peaks of the resonance system by the third diaphragm can be realized. Further, vibrations in a minute amplitude high frequency region such as a booming noise and acceleration noise can be reduced by resonance between the third orifice channel and the second diaphragm. Therefore, it is possible to realize a characteristic having two-peak attenuation with respect to the vibration in the low frequency range and the small amplitude while satisfying the anti-vibration performance against the vibration in the high amplitude range and the high amplitude range.

1 is a longitudinal sectional view of a liquid-filled vibration isolator according to an embodiment of the present invention. Schematic diagram of the same liquid-sealed vibration isolator Sectional view of the partition part of the liquid-sealed vibration isolator The exploded perspective view seen from the diagonal upper part of the partition part Exploded perspective view of the partition seen from diagonally below A graph showing the spring characteristics of a liquid-filled vibration isolator during minute amplitude vibration A graph showing the damping characteristics of a liquid-filled vibration isolator during minute amplitude vibration Graph showing anti-vibration characteristics of liquid-sealed anti-vibration device during large amplitude vibration Schematic diagram of a conventional liquid-filled vibration isolator

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  The liquid-filled vibration isolator 10 according to the embodiment shown in FIGS. 1 and 2 is an engine mount that supports an automobile engine, and includes an upper first attachment 12 that is attached to an engine that is a vibration source, and a support side. And a vibration-proof base 16 made of a rubber elastic body that is interposed between the two attachments 12 and 14 and connects them. Become.

  The 1st fixture 12 is the boss | hub metal fitting distribute | arranged above the axial center part of the 2nd fixture 14, and the stopper part 18 which protrudes in a flange shape toward radial direction outward is formed. Moreover, the bolt hole 20 is provided in the upper end part, and it is comprised so that it may attach to an engine side via a volt | bolt not shown.

  The second fixture 14 is a main body metal fitting composed of a cylindrical cylindrical body 22 and a cup-shaped bottom member 24 on which the vibration-isolating base 16 is vulcanized, and a mounting bolt 26 faces downward on the bottom member 24. It protrudes and is configured to be attached to the vehicle body side via this bolt 26. The lower end portion of the cylindrical body 22 is caulked and fixed to the upper end opening of the bottom member 24 by caulking portions 28. A stopper fitting 30 is caulked and fixed to the upper end portion of the cylindrical body portion 22 and exerts a stopper action with the stopper portion 18 of the first fixture 12.

  The anti-vibration base 16 is formed in a substantially umbrella shape, and its upper end is vulcanized and bonded to the first fixture 12 and its lower end is vulcanized and bonded to the upper end opening of the cylindrical body 22. A rubber film-like seal wall portion 32 that covers the inner peripheral surface of the cylindrical body portion 22 is connected to the lower end portion of the vibration isolation base 16.

  A first diaphragm 36 made of a flexible rubber film is attached to the second fixture 14 so as to face the lower surface of the vibration isolating base 16 in the axial direction X and form a liquid chamber 34 between the lower surface. The liquid chamber 34 is filled with a liquid such as water, ethylene glycol, or silicone oil. The first diaphragm 36 includes an annular reinforcing bracket 38 on the outer peripheral portion, and is fixed to the caulking portion 28 via the reinforcing bracket 38. The first diaphragm 36 has a cross-sectional wave shape in which an outer peripheral portion once bulges downward in a curved shape and then a central portion bulges upward in a curved shape.

  The liquid chamber 34 provided on the inner side of the second fixture 14 is provided on the side of the vibration isolating base 16 (ie, the upper side) by a disk-shaped partition portion 40 fitted inside the peripheral wall portion of the second fixture 14. The main liquid chamber 42 and the first sub liquid chamber 44 on the first diaphragm 36 side (that is, the lower side) are partitioned. The main liquid chamber 42 is a liquid chamber in which the vibration isolation base 16 forms a part of the chamber wall, and the first sub liquid chamber 44 is a liquid chamber in which the first diaphragm 36 forms a part of the chamber wall. The partition 40 includes a second sub liquid chamber 48 that is partitioned from the first sub liquid chamber 44 by a second diaphragm 46 made of a flexible rubber film, and a third diaphragm 50 made of a flexible rubber film. A third sub liquid chamber 52 that is partitioned from the one sub liquid chamber 44 is provided.

  The partition 40 has a first orifice channel 60 that communicates the main liquid chamber 42 and the first sub-liquid chamber 44, and a second orifice channel 62 that communicates the second sub-liquid chamber 48 and the third sub-liquid chamber 52. And a third orifice channel 64 for communicating the main liquid chamber 42 and the second sub-liquid chamber 48, and a switching valve 66 for opening and closing the third orifice channel 64 according to the input amplitude is provided in the third orifice channel. 64.

  The first orifice channel 60 is tuned to a corresponding frequency range (for example, about 5 to 20 Hz) in order to attenuate engine shake vibration during vehicle travel. That is, the tuning is performed by adjusting the cross-sectional area and length of the flow path so that the damping effect based on the resonance action of the liquid flowing through the first orifice flow path 60 is effectively exhibited against the vibration in the frequency range. Has been.

  The second orifice channel 62 is an orifice channel that is tuned to a higher frequency range than the first orifice channel 60 and to a lower frequency range than the third orifice channel 64. Here, in order to reduce vibrations in a frequency range such as an explosion primary component of an engine among idle vibrations, a moment (for example, about 20 to 40 Hz) corresponding to this is output to the vehicle ( Nm) is tuned so as to effectively exhibit the attenuation effect. That is, it is tuned by adjusting the cross-sectional area and length of the flow path so that the damping effect based on the resonance action of the liquid flowing through the second orifice flow path 62 is effectively exhibited when the idle vibration is input. Yes.

  The third orifice channel 64 is an orifice channel tuned to a higher frequency range than the second orifice channel 62. Here, in order to reduce vibration / noise in a high frequency range such as a booming noise and acceleration noise, tuning is performed in the high frequency range (for example, about 80 to 200 Hz). That is, the cross-sectional area and the length of the flow path are adjusted so that the low dynamic spring effect based on the resonance action of the liquid flowing through the third orifice flow path 64 is effectively exhibited at the time of vibration input in the high frequency range. Has been tuned by.

  Specifically, as shown in FIG. 3, the partition portion 40 includes a partition portion main body 54 that forms a second sub liquid chamber 48 and a third sub liquid chamber 52 inside, and an upper surface that covers the upper surface of the partition portion main body 54. It consists of a wall 56 and a receiving plate 58 that receives the lower surface of the partition body 54. The partition portion 40 fixes the receiving plate portion 58 together with the reinforcing metal fitting 38 to the caulking portion 28, so that the partition portion 40 is axially disposed between the step portion 32 </ b> A provided on the seal wall portion 32 and the receiving plate portion 58 (that is, (Vertical direction) is held between X.

  As shown in FIGS. 3 to 5, the partition body 54 is provided with an arcuate cavity 68 that forms the second secondary liquid chamber 48 and a circular recess that forms the third secondary liquid chamber 52. 70 is provided to open downward. The receiving plate portion 58 is formed of a disk-shaped metal fitting in which the second diaphragm 46 and the third diaphragm 50 are vulcanized and bonded, and covers the recess 70 at a portion where the third diaphragm 50 is provided, thereby separating the partition portion main body. A third sub liquid chamber 52 is formed between the first sub liquid chamber 52 and the second sub liquid chamber 52. Further, the cavity portion 68 is covered from the lower surface at the portion of the receiving plate portion 58 where the second diaphragm 46 is provided, and the upper surface of the partition portion main body 54 is covered by the upper wall portion 56, whereby the upper wall portion 56 and the partition portion are covered. A second sub liquid chamber 48 is formed between the main body 54 and the receiving plate portion 56. The third diaphragm 50 has a shape that bulges upward in a curved shape, and has a larger expansion elasticity than the first diaphragm 36. The second diaphragm 46 has a thin flat plate shape, and its expansion elasticity is set larger than that of the first diaphragm 36 and the third diaphragm 50.

  A first concave groove 72 extending in the circumferential direction is provided on the outer peripheral surface of the partition portion main body 54, and the first concave groove 72 and the seal wall portion 32 extend in the circumferential direction as shown in FIG. 1. An orifice channel 60 is formed. The first orifice channel 60 has a main liquid chamber side opening 60A (see FIG. 4) that opens to the main liquid chamber 42 side at one end in the circumferential direction, and the first sub liquid chamber 44 side to the other end in the circumferential direction. The first sub liquid chamber side opening 60 </ b> B (see FIG. 5) opens, and thereby the main liquid chamber 42 and the first sub liquid chamber 44 communicate with each other.

  The second orifice channel 62 is formed by a second groove 73 provided around the recess 70 on the lower surface side of the partition body 54 and a third groove 74 provided on the lower surface side of the upper wall portion 56. The upper and lower stages are formed (see FIGS. 3 and 5). The second concave groove 73 and the third concave groove 74 are connected via a through hole 75 (see FIG. 4) provided in the partition portion main body 54. One end 62A of the second orifice channel 62 opens into the second secondary liquid chamber 48, and the other end 62B opens into the third secondary liquid chamber 52 (see FIG. 5).

  The third orifice channel 64 includes a switching valve 66 so that the flow of the liquid in the third orifice channel 64 is regulated by the switching valve 66 when a vibration having a predetermined amplitude or more (for example, ± 0.3 mm or more) is input. It is configured as follows.

  As shown in FIGS. 3 to 5, the switching valve 66 includes a valve main body 76 made of a flexible rubber film whose outer peripheral portion 76 </ b> A is liquid-tightly held by the partition portion 40. A pair of restricting plates 78 and 79 for restricting the bending deformation of the valve body 76 are provided. Both restriction plates 78 and 79 are provided with a communication hole 80 constituting the third orifice flow path 64, and the valve body 76 is provided with a through hole 81 at a position not overlapping the communication hole 80. The switching valve 66 is configured to close the third orifice channel 64 by closing the communication hole 80 due to the bending deformation.

  In this example, the upper wall portion 56 is provided with a lower regulating plate 78 and is fixed to the upper surface of the partition body 54, and an upper regulating plate 79 is provided on the upper surface of the first member 82. A second member 84 to be fixed, and a valve body 76 in which an outer peripheral portion 76A is sandwiched liquid-tightly by the first member 82 and the second member 84 are configured. The upper and lower restricting plates 78 and 79 are provided with a plurality of circular communication holes 80 penetrating each other. The communication holes 80 are sized and positioned so as to overlap each other between the upper and lower restricting plates 78 and 79. Is set. The upper and lower regulating plates 78 and 79 are arranged so as to face each other with a predetermined gap with respect to the front and back membrane surfaces of the valve body 76.

  The valve body 76 has a disc shape, and an outer peripheral portion 76A sandwiched between upper and lower restricting plates 78 and 79 is formed thick. On the front and back membrane surfaces of the valve main body 76, reinforcing ribs 86 are provided in portions that close the communication holes 80 (that is, portions that face the communication holes 80). The ribs 86 are radial so as to connect the annular rib 86A along the outer peripheral edge of each communication hole 80, the circular convex portion 86B located at the center of the communication hole 80, and the annular rib 86A and the convex portion 86B. And a radial rib 86 </ b> C extending in the direction. By providing the rib 86, when the communication hole 80 is closed during large amplitude vibration, the valve body 76 can be prevented from being broken by being sucked into the communication hole 80 and excessively deformed.

  The valve body 76 is provided with a plurality of through-holes 81 in a portion where the rib 86 is not provided, so that liquid flows between the main liquid chamber 42 and the second sub liquid chamber 48. It communicates so that it can do. In this example, the total cross-sectional area of the plurality of through-holes 81 is set to the same value as the total cross-sectional area of the communication holes 80 provided in the restricting plates 78 and 79, and the through-hole 81 is also the third orifice channel. 64. In other words, the third orifice channel 64 opens into the main liquid chamber 42 through the communication hole 80 of the upper restriction plate 79 and passes through the through hole 81 of the valve body 76 from the communication hole 80 to the lower restriction plate. The second sub liquid chamber 52 is formed to open from the 78 communication holes 80.

  With this configuration, the switching valve 66 bends when the valve main body 76 is bent when the vibration is input with a larger amplitude than that of the open state when the third orifice channel 64 is opened during the minute amplitude vibration. The third orifice channel 64 is switched to a closed state in which the third orifice channel 64 is closed by deforming and closing the communication hole 80.

  In the liquid-filled vibration isolator 10 having the above-described configuration, the third orifice flow path 64 is closed by the switching valve 66 against a large-amplitude vibration in a low frequency region such as an engine shake. Therefore, of the first to third orifice channels, the liquid flow occurs only in the first orifice channel 60 that communicates the main liquid chamber 42 and the first sub-liquid chamber 44 (first state). Therefore, the damping effect is exhibited by the resonance action determined by the spring constant of the first orifice channel 60 and the first diaphragm 36, and the input vibration is reduced.

  For vibrations in a low amplitude region such as an idle vibration, the third orifice channel 64 is opened by the switching valve 66, so that the second orifice channel 62 and the second orifice channel 60 and the first orifice channel 60 are opened. Liquid flow also occurs in the three-orifice channel 64 (second state). Since the tuning frequency of the third orifice channel 64 is set high, the characteristics of the input vibration are determined by the resonance of the first orifice channel 60 and the second orifice channel 62 and the spring constant of the second diaphragm 46. Is decided. At this time, the resonance frequency of the first orifice channel 60 is determined by the spring constant of the first diaphragm 36, and the resonance frequency of the second orifice channel 62 is determined by the spring constant of the third diaphragm 50. The characteristic with can be realized.

  The third orifice flow path 64 is opened by the switching valve 66 against vibrations in a fine amplitude and high frequency range such as a booming noise and acceleration noise. At this time, since the first orifice channel 60 and the second orifice channel 62 having a low tuning frequency are clogged, the liquid flow occurs only in the third orifice channel 64 (third state). ). Therefore, the input vibration can be reduced by resonance between the third orifice channel 64 and the second diaphragm 46. That is, the second diaphragm 46 is effective, and a low dynamic spring can be realized.

  As described above, according to the present embodiment, while satisfying the anti-vibration performance against the large-amplitude vibration such as the engine shake and the low-amplitude high-frequency vibration such as the booming noise, the fine-amplitude low frequency such as the idle vibration It is possible to realize a characteristic having a two-peak attenuation with respect to the vibration in the region, and to satisfy the demand for idle vibration at a higher level.

  6 to 8 are graphs showing the vibration isolation characteristics of the liquid filled vibration isolator 10 of the above embodiment together with the liquid filled vibration isolator according to the comparative example having the configuration shown in FIG. In the figure, K represents a storage (dynamic) spring constant of the vibration isolator according to the embodiment, and K ′ represents a storage (dynamic) spring constant of the vibration isolator according to the comparative example. C represents the attenuation coefficient of the vibration isolator according to the embodiment, and C ′ represents the attenuation coefficient of the vibration isolator according to the comparative example.

  As shown in FIG. 8, at the time of large amplitude vibration input corresponding to engine shake (± 0.50 mm), the embodiment and the comparative example have the same characteristics in both the storage spring constant and the damping coefficient, and the low frequency range. Excellent damping performance was obtained.

  As shown in FIGS. 6 and 7, with respect to the vibration input (± 0.05 mm) having a small amplitude corresponding to the idle vibration, the comparative example has a low frequency range of 50 Hz or less with respect to the damping coefficient (C ′). In contrast, the attenuation coefficient (C) of the embodiment has a first peak due to resonance of the first orifice channel 60 to about 5 to 20 Hz, and 25 to 40 Hz. The second peak due to the resonance of the second orifice channel 62 could be realized to the extent. Moreover, also about the storage spring constant, in the thing (K) of embodiment, the storage spring constant of around 50 Hz was reducing. Further, in the high frequency range of about 100 to 140 Hz corresponding to the booming noise and the acceleration noise, the action of the second diaphragm 46 has a low storage spring constant and a low spring is achieved.

  In the above embodiment, the first fixture 12 is attached to the vibration source side and the second fixture 14 is attached to the support side. Conversely, the first fixture 12 is attached to the support side. The second fixture 14 may be attached to the vibration source side. In addition, the switching valve 66 provided in the third orifice flow path 64 is only an example of the above embodiment, and is not limited thereto. Although not enumerated one by one, various modifications can be made without departing from the spirit of the present invention.

  The present invention can be used for various vibration isolators such as a mount that supports other power units such as a motor, a body mount, and a differential mount, in addition to an engine mount.

DESCRIPTION OF SYMBOLS 10 ... Liquid enclosure type vibration isolator 12 ... 1st attachment 14 ... 2nd attachment 16 ... Anti-vibration base | substrate 34 ... Liquid chamber 36 ... 1st diaphragm 40 ... Partition part 42 ... Main liquid chamber 44 ... 1st sub liquid chamber 46 ... Second diaphragm 48 ... Second sub-liquid chamber 50 ... Third diaphragm 52 ... Third sub-liquid chamber 60 ... First orifice channel 62 ... Second orifice channel 64 ... Third orifice channel 66 ... Switching valve 76 ... Valve body 76A ... Outer peripheral part of valve body 78, 79 ... Restriction plate 80 ... Communication hole 81 ... Through hole X ... Axial direction

Claims (4)

A first fixture attached to one of the vibration source side and the support side;
A second fixture attached to the other of the vibration source side and the support side;
An anti-vibration base made of a rubber-like elastic body interposed between the first fixture and the second fixture;
A main liquid chamber in which a liquid in which the vibration isolating substrate forms a part of a chamber wall is enclosed;
A first sub-liquid chamber in which a liquid in which a first diaphragm made of a rubber-like elastic film forms part of a chamber wall is enclosed;
A second sub-liquid chamber that is partitioned from the first sub-liquid chamber by a second diaphragm made of a rubber-like elastic film and in which a liquid is enclosed;
A third sub-liquid chamber that is partitioned from the first sub-liquid chamber by a third diaphragm made of a rubber-like elastic film and in which a liquid is enclosed;
A first orifice channel for communicating the main liquid chamber and the first sub liquid chamber;
A second orifice channel that is tuned to a higher frequency range than the first orifice channel and communicates the second sub-liquid chamber and the third sub-liquid chamber;
A third orifice channel that is tuned to a higher frequency range than the second orifice channel and communicates the main liquid chamber and the second sub-liquid chamber;
A switching valve provided in the third orifice channel for opening and closing the third orifice channel, wherein the third orifice channel is opened and when a vibration having a larger amplitude than the opened state is input. A switching valve for switching to a closed state for closing the third orifice channel;
Equipped with a,
A first state in which a liquid flow occurs only in the first orifice channel among the first, second and third orifice channels by closing the third orifice channel by the switching valve; A second state in which liquid flows in the first, second, and third orifice channels when the third orifice channel is opened by the switching valve, and a higher frequency region than the second state. Having a third state in which the first orifice channel and the second orifice channel are clogged by vibration input and a liquid flow occurs only in the third orifice channel;
Liquid-filled vibration isolator. The second fixture has a cylindrical shape, and the first diaphragm is attached to the second fixture to form a liquid chamber in which a liquid is sealed between the anti-vibration base, and the liquid chamber is the first chamber. 2 The main liquid chamber and the first sub liquid chamber are partitioned by a partition portion fitted inside the peripheral wall portion of the fixture, and the second sub liquid chamber and the third sub liquid chamber are formed in the partition portion. liquid chamber, said first orifice passage, said second orifice passage, the third hydraulic antivibration device according to claim 1, wherein the orifice passage and the selector valve is provided. The switching valve includes a valve main body made of a rubber-like elastic film whose outer peripheral portion is liquid-tightly held in the partition portion, and a pair of restriction plates for restricting bending deformation of the valve main body are provided on both front and back sides of the valve main body. The restriction plate is provided with a communication hole that constitutes the third orifice flow path, and the valve body is provided with a through hole at a position that does not overlap the communication hole. The liquid-filled type vibration damping device according to claim 2 , wherein the switching valve is configured to close the third orifice channel when the hole is closed. A first fixture attached to one of the vibration source side and the support side;
A second fixture attached to the other of the vibration source side and the support side;
An anti-vibration base made of a rubber-like elastic body interposed between the first fixture and the second fixture;
A main liquid chamber in which a liquid in which the vibration isolating substrate forms a part of a chamber wall is enclosed;
A first sub-liquid chamber in which a liquid in which a first diaphragm made of a rubber-like elastic film forms part of a chamber wall is enclosed;
A second sub-liquid chamber that is partitioned from the first sub-liquid chamber by a second diaphragm made of a rubber-like elastic film and in which a liquid is enclosed;
A third sub-liquid chamber that is partitioned from the first sub-liquid chamber by a third diaphragm made of a rubber-like elastic film and in which a liquid is enclosed;
A first orifice channel for communicating the main liquid chamber and the first sub liquid chamber;
A second orifice channel that is tuned to a higher frequency range than the first orifice channel and communicates the second sub-liquid chamber and the third sub-liquid chamber;
A third orifice channel that is tuned to a higher frequency range than the second orifice channel and communicates the main liquid chamber and the second sub-liquid chamber;
A switching valve provided in the third orifice channel for opening and closing the third orifice channel, wherein the third orifice channel is opened and when a vibration having a larger amplitude than the opened state is input. A switching valve for switching to a closed state for closing the third orifice channel;
With
The second fixture has a cylindrical shape, and the first diaphragm is attached to the second fixture to form a liquid chamber in which a liquid is sealed between the anti-vibration base, and the liquid chamber is the first chamber. 2 The main liquid chamber and the first sub liquid chamber are partitioned by a partition portion fitted inside the peripheral wall portion of the fixture, and the second sub liquid chamber and the third sub liquid chamber are formed in the partition portion. A liquid chamber, the first orifice channel, the second orifice channel, the third orifice channel, and the switching valve;
The switching valve includes a valve main body made of a rubber-like elastic film whose outer peripheral portion is liquid-tightly held in the partition portion, and a pair of restriction plates for restricting bending deformation of the valve main body are provided on both front and back sides of the valve main body. The restriction plate is provided with a communication hole that constitutes the third orifice flow path, and the valve body is provided with a through hole at a position that does not overlap the communication hole. The switching valve is configured to close the third orifice flow path by closing the hole ,
Liquid-filled vibration isolator.

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