JP2001020994A - Vibration isolator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase an area of a pressure displacement part on a driving bulkhead to change the inside of a pressure liquid chamber as well as to sufficiently increase amplitude of the driving bulkhead at the time of supplying pressure to a gas sealing chamber. SOLUTION: A change-over valve 99 is connected to a gas sealing chamber 81 through a piping 97, and a supply pipe 103 communicated to an intake manifold 101 and a pressure releasing pipe 105 communicated to an outside space are respectively connected to this change-over valve 99. The piping 97 and the intake manifold 101 are communicated to each other by the change-over valve 99 on a vibration isolator 10, when the inside of the gas sealing chamber becomes negative pressure, a diaphragm 79 contracts and moves the driving bulkhead 53 downward against resiliency of a coil spring 91, thereafter, the piping 97 and the pressure releasing pipe 103 are communicated to each other by the change-over valve 99, and when the inside of the gas sealing chamber 81 becomes atmospheric pressure from negative pressure, the driving bulkhead 53 moves upward by restoring force of the coil spring 91.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to, for example, automobiles,
The present invention relates to a liquid-filled type vibration damping device that is applied to general industrial machines and the like and attenuates vibration transmitted from a vibration generating unit to a vibration receiving unit.

[0002]

2. Description of the Related Art A vibration isolator used as an engine mount of an automobile is provided with a pressure receiving liquid chamber having an elastic body as a part of an inner wall and a sub-liquid chamber communicating with the pressure receiving liquid chamber through a restriction passage (orifice). There is a liquid filling type. According to this liquid-filled type vibration damping device, the elastic body is deformed at the time of vibration input from the engine, and at the same time, the liquid flows between the pressure receiving liquid chamber and the sub liquid chamber through the orifice, whereby the liquid Vibration energy can be effectively absorbed by column resonance or the like.

In a liquid-filled type vibration damping device, the whole or a part of a partition (drive partition) that partitions a pressure receiving liquid chamber and a gas charging chamber provided adjacent to the pressure receiving liquid chamber is made of rubber. There is a hydraulic pressure control type vibration damping device which is formed and elastically deforms the driving partition wall so as to be displaceable in the direction of volume expansion and contraction of the pressure receiving liquid chamber, and alternately supplies negative pressure and atmospheric pressure to the gas filled chamber.

[0004] In the above-mentioned hydraulic control type vibration damping device, the driving partition is elastically deformed toward the expansion and contraction of the capacity of the pressure receiving liquid chamber due to a change in the air pressure in the gas filled chamber, so that the liquid pressure in the pressure receiving liquid chamber is activated. If the hydraulic pressure in the pressure receiving liquid chamber is changed at a cycle corresponding to the vibration frequency, the rise in the dynamic spring constant can be effectively suppressed in a wide frequency range, and transmitted to the vibration receiving section. Even if the frequency range of the vibration is wide, a high vibration isolation effect can be maintained.

[0005]

However, in the above-described hydraulic control type vibration damping device, when the entire driving partition is formed of rubber, the pressure receiving surface of the driving partition is supplied when the pressure is supplied to the gas filled chamber. The central portion is elastically deformed so as to be convex or concave. For this reason, the area of the pressurizing displacement portion that substantially changes the liquid pressure of the pressure receiving liquid chamber in the driving partition is reduced, and the liquid pressure in the pressure receiving liquid chamber can be efficiently changed even when the driving partition is vibrated. Can not.

Further, even when a part of the driving partition is formed of rubber, the rigidity of the rubber portion of the driving partition must be reduced in order to increase the amplitude of the driving partition when supplying pressure to the gas filled chamber. . On the other hand, the rigidity of the rubber portion of the drive partition wall needs to be large enough to withstand the hydraulic pressure in the pressure receiving liquid chamber. For this reason, the thickness and shape of the rubber portion of the drive partition are restricted, and if the rigidity of the rubber portion is reduced to increase the amplitude of the drive partition, the projected area along the volume expansion and contraction direction of the rubber portion is designed by design. (Hereinafter, referred to as a pressure receiving area) must be widened, and the area of the pressure displacement portion that substantially changes the liquid pressure of the pressure receiving liquid chamber in the drive partition wall decreases. Conversely, when the pressure receiving area of the rubber portion is reduced and the area of the pressure displacement portion in the drive partition is increased, the rigidity of the rubber portion is increased and the amplitude of the drive partition is reduced, resulting in a contradictory phenomenon.

SUMMARY OF THE INVENTION In view of the above facts, it is an object of the present invention to sufficiently increase the amplitude of a driving partition at the time of supplying pressure to a gas-filled chamber and to increase the area of a pressure displacement portion in the driving partition which changes the pressure-receiving liquid chamber. An object of the present invention is to provide a vibration isolator that can be enlarged.

[0008]

According to a first aspect of the present invention, there is provided a vibration isolator connected to one of a vibration generator and a vibration receiver, and a first mounting member connected to the other of the vibration generator and the vibration receiver. A second mounting member to be provided, an elastic body disposed between the first mounting member and the second mounting member, and an inner volume that is reduced by deformation of the elastic body with the elastic body being a part of a partition wall. The pressure-receiving liquid chamber that expands and contracts and constitutes another part of the partition wall in the pressure-receiving liquid chamber, and is capable of being displaced along the volume expansion and contraction direction of the pressure-receiving liquid chamber by elastic deformation of a rubber portion provided on an outer peripheral portion. A driving partition, a spring member elastically supporting the pressurized displacement section along the volume expansion / contraction direction, a gas sealing chamber adjacent to the pressure receiving liquid chamber with the driving partition interposed therebetween, and a gas sealing chamber. It constitutes a partition and is connected to the drive partition, and the inside of the gas filled chamber is formed. An elastic film that expands and contracts along the volume expansion and contraction direction according to a pressure change and displaces the driving partition wall; and a pressure supply source and an external space in which the gas filled chamber is set to a negative pressure or a positive pressure with respect to the external space. Pressure supply means alternately communicating with any of the pressure supply means.

According to the vibration damping device having the above-described structure, the pressure supply means alternately communicates the gas-filled chamber with the external space and the pressure supply source which is set to a negative pressure or a positive pressure with respect to the external space. When the gas chamber is communicated with the pressure supply source, the pressure in the gas chamber becomes positive or negative with respect to the pressure in the external space (external air pressure). When the gas chamber is communicated with the external space, the gas chamber becomes gaseous. Becomes equal to the external pressure.

At this time, when the pressure of the gas-filled chamber becomes negative with respect to the atmospheric pressure of the external space, the elastic film is deformed so as to contract in the direction of expansion and contraction of the volume of the pressure-receiving liquid chamber. When the pressure becomes positive with respect to the atmospheric pressure, the elastic membrane is deformed so as to extend in the volume expansion / contraction direction, so that the driving partition wall connected to the elastic membrane opposes the urging force of the spring member and the volume of the pressure-receiving liquid chamber is increased. It is displaced in the expansion direction or the volume reduction direction, and a hydraulic pressure change occurs in the pressure receiving liquid chamber in accordance with the displacement direction and the displacement amount of the drive partition. Thereafter, when the pressure in the gas filled chamber becomes equal to the external air pressure, the driving partition wall is displaced in the direction opposite to the negative pressure or the positive pressure by the restoring force of the spring member, and the displacement direction and the displacement amount of the driving partition wall in the pressure receiving liquid chamber. The hydraulic pressure changes according to the pressure.

Therefore, if the communication destination of the gas filled chamber is alternately switched between the pressure supply source and the external space at a period corresponding to the vibration transmitted to the vibration receiving portion, the hydraulic pressure in the pressure receiving liquid chamber during the transmission of the vibration is reduced. Since active control can be performed, even when the vibration transmitted to the vibration receiving portion changes over a wide frequency range, an increase in the dynamic spring constant due to an increase in the hydraulic pressure in the pressure receiving liquid chamber can be suppressed. As a result, the vibration from the vibration generating section can be effectively attenuated by the internal resistance of the elastic body or the like.

Further, since the driving partition is elastically supported by the spring member, it is necessary to adjust the rigidity of the rubber portion of the driving partition to set the amplitude of the driving partition when the pressure is supplied to the gas filling chamber. The rigidity of the rubber portion can be reduced by forming the rubber portion with a low-rigidity rubber material. Thus, the pressure receiving area of the rubber portion in the drive partition can be reduced, and the area of the pressure displacement portion can be sufficiently increased. Further, since the spring constant of the spring member can be easily set as compared with rubber, the amplitude of the drive partition wall at the time of supplying pressure to the gas filled chamber can be made sufficiently large.

According to a second aspect of the present invention, in the vibration isolator according to the first aspect, the pressure supply means communicates with the gas filling chamber at a period corresponding to the vibration transmitted to the vibration receiving portion. The pressure supply source and the external space are alternately switched.

According to the vibration damping device having the above structure, the pressure supply means alternately switches the communication destination of the gas-filled chamber between the pressure supply source and the external space at a cycle corresponding to the vibration transmitted to the vibration receiving portion. This makes it possible to actively control the liquid pressure in the pressure receiving liquid chamber at a period corresponding to the vibration transmitted to the vibration receiving unit. By displacing the drive partition so as to cancel the pressure rise, it is possible to suppress the dynamic spring constant from increasing due to the rise in the liquid pressure in the pressure receiving liquid chamber, so that vibration in a specific frequency range is effectively reduced by the internal resistance of the elastic body, etc. Can be attenuated.

According to a third aspect of the present invention, in the vibration isolator according to the first or second aspect, the pressure supply means is connected to an intake manifold of the engine using the gas-filled chamber as a pressure supply source. And a pressure release path connecting the gas filled chamber to an external space, and an on-off valve for opening and closing the pressure supply path and the pressure release path, respectively.

According to the vibration damping device having the above structure, the pressure supply path connects the gas filling chamber to the intake manifold of the engine as a pressure supply source, so that the pressure in the intake manifold is negative with respect to the external pressure when the engine is operating. When the pressure supply path is opened by the on-off valve and the pressure release path is closed, the pressure in the gas filled chamber can be reduced to a negative pressure, and the pressure supply path is closed by the on-off valve, and When the pressure release passage is open, the inside of the gas filled chamber can be made equal to the outside air pressure. As a result, when the apparatus is applied to an automobile or the like, it is not necessary to provide a special pressure supply source for supplying a negative pressure or a positive pressure.

According to a fourth aspect of the present invention, there is provided an anti-vibration device according to the first and second aspects.
Or the vibration isolator according to 3, wherein a part of the partition is formed of a diaphragm and a liquid is sealed therein, and a sub-liquid chamber whose internal volume expands / contracts due to deformation of the diaphragm; and the pressure-receiving liquid chamber is a sub-liquid chamber. And a communicating restricted passage.

According to the vibration damping device having the above structure, if the rigidity of the diaphragm and the flow resistance of the liquid in the restriction passage are set in accordance with the specific vibration frequency, the pressure receiving liquid chamber and the auxiliary liquid chamber can be set when the vibration of the specific frequency is input. Liquid column resonance can be generated through a restriction passage between the liquid crystal and the liquid, so that vibration energy is absorbed by a flow resistance of the liquid or a change in liquid pressure, and vibration of a specific frequency (eg, shake vibration) can be effectively attenuated. .

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a vibration isolator according to an embodiment of the present invention will be described with reference to the drawings.

(First Embodiment) FIG. 1 shows a vibration isolator 10 according to a first embodiment. The anti-vibration device 10 is applied as an anti-vibration mount for an engine in an automobile. The symbol S in the figure indicates an axis which is a center line of the apparatus, and the following description will be made with a direction along this axis as an axial direction.

FIG. 1 shows a vibration isolator 10 according to a first embodiment of the present invention. This anti-vibration device 10
Has a bottomed cylindrical outer tube fitting 18 as a mounting member. The outer cylindrical member 18 is provided with an upper cylindrical portion 20 and a lower cylindrical portion 22 having different diameters along the axial direction, and is provided between the large-diameter upper cylindrical portion 20 and the small-diameter lower cylindrical portion 22. A stepped flange portion 24 is formed in the portion.

A bolt 26 is fixed to the bottom plate of the outer tube fitting 18 by welding or the like, and the shaft of the bolt 26 projects downward along the axis S. The bolt 26 penetrates the vehicle body 12, and a nut 28 is screwed into a tip of the bolt 26. Thereby, the outer tube fitting 18 is fastened and fixed to the vehicle body 12.

In the upper cylindrical portion 20, thin supporting cylinders 30 whose both axial ends are larger than the inner diameter of the lower cylindrical portion 22 are inserted. A reduced diameter portion 3 having a small diameter with respect to both ends is provided at an axially intermediate portion of the support cylinder 30.
1 is provided. The reduced diameter portion 31 has a groove 33 having a rectangular cross section formed along the circumferential direction on the outer peripheral surface of the support cylinder 30 over the entire circumference.

An elastic body 35 made of rubber is bonded to the inner peripheral surface of the support cylinder 30 by vulcanization. The elastic body 35 is formed in a substantially truncated conical shape whose cross section is reduced upward, and the vicinity of the outer periphery at the lower end is vulcanized and bonded to the upper end of the inner peripheral surface of the support cylinder 30, and the upper end is supported cylinder It protrudes upward from 30. Further, a circular concave portion 37 which is depressed upward is formed at the center of the bottom surface of the elastic body 35.

A metal top plate 39 is vulcanized and bonded to the top surface of the elastic body 35. A bolt shaft 41 is fixed to the upper surface of the top plate fitting 39 by welding or the like so as to protrude upward along the axis S. An end of an engine bracket (not shown) serving as a vibration generating unit is mounted on the top plate fitting 39, a bolt shaft 41 passes through a mounting hole provided at an end of the bracket, and a nut is screwed into the end. . As a result, the top plate fitting 39 as an attachment member is connected to the engine.

A substantially cylindrical partition member 4 is provided in the support cylinder 30.
7 is inserted. A cylindrical hollow portion 49 penetrating in the axial direction is formed on the inner peripheral side of the partition member 47, and a partition housing portion 51 having an inner diameter that is larger than the upper side is formed at the lower end of the hollow portion 49. Is formed. Here, the partition member 47 is arranged such that the outer peripheral portion of the upper surface is in close contact with the peripheral portion of the concave portion 37 of the elastic body 35. The inner diameter of the hollow portion 49 is smaller than the inner diameter of the concave portion 37 of the elastic body 35.

A disk-shaped drive partition 53 is arranged in the partition storage portion 51 of the partition member 47. The driving partition 53 is
It is composed of a disk-shaped rigid plate 154 made of metal or resin disposed on the inner peripheral side, and a rubber elastic ring 55 disposed on the outer peripheral side of the rigid plate 54.

The elastic ring 55 has an inner peripheral surface adhered to the outer peripheral surface of the rigid plate 54 and an outer peripheral surface adhered to the inner peripheral surface of the partition wall accommodating portion 51. Thus, the hollow portion 49 of the partition member 47 is closed by the driving partition 53. Here, the concave portion 37 of the elastic body 35 and the hollow portion 49 closed by the drive partition wall 53 constitute a pressure receiving liquid chamber 57. When the pressure receiving liquid chamber 57 is elastically deformed along the axial direction, Its inner volume changes. The drive partition wall 53 can be displaced along an axial direction which is a direction in which the volume of the pressure receiving liquid chamber 57 is expanded or contracted by the elastic deformation of the elastic ring 55.

As shown in FIG. 2, a groove 48 is formed on the outer peripheral surface of the partition member 47 along the circumferential direction, and one end of the groove 48 is formed from the inner wall of the groove 40 to the inner peripheral surface of the hollow portion 49. A communication path 59 penetrating therethrough is formed.

As shown in FIG. 1, the support cylinder 30 has the inner peripheral surface of the reduced diameter portion 31 in close contact with the outer peripheral surface of the partition member 47. Thus, the outer peripheral side of the groove 33 of the partition member 47 is closed by the reduced diameter portion 31. As shown in FIG. 2, a through hole 61 is formed in the reduced diameter portion 31 of the support cylinder 30 at a position corresponding to the other end of the groove 40, and the through hole 61 is formed in the groove 33 of the support cylinder 30. And the groove 48 of the partition member 47 communicate with each other.

At the lower end of the outer peripheral surface of the partition member 47, a ring-shaped flange 63 extending in the radial direction is formed.
The upper surface of the flange 63 is in contact with the lower surface of the reduced diameter portion 31 of the support cylinder 30. In addition, a cylindrical connecting fitting 64 is disposed below the flange 63 in the outer cylindrical fitting 18. A ring-shaped flange 65 extending in the radial direction is provided at the upper end of the connection fitting 64.
4 is the flange portion 65 of the partition member 7
3 and the flange portion 24 of the outer tube fitting 18. The lower side of the connection fitting 64 is inserted into the lower cylindrical portion 22 of the outer cylinder fitting 18 and covers most of the inner peripheral surface of the lower cylinder 22.

On the other hand, a thin intermediate cylinder 69 is disposed in the upper cylindrical portion 20 of the outer cylinder fitting 18 between the outer cylinder and the outer peripheral surface of the support cylinder 30. The length of the intermediate cylinder 69 in the axial direction is equal to that of the support cylinder 30, and the inner peripheral surface covers the outer peripheral surface of the support cylinder 30. The lower end portions of the support cylinder 30 and the intermediate cylinder 69 are in contact with the upper surface of the flange portion 24 of the outer cylinder fitting 18, respectively.
Is crimped to the inner peripheral side so that the support cylinder 30, the intermediate cylinder 69, and the connection fitting 64 are connected to the outer cylinder fitting 18
Fixed within.

On the inner peripheral surface of the intermediate cylinder 69, both ends in the axial direction of a rubber diaphragm 71 having a substantially cylindrical shape are respectively vulcanized and bonded over the entire circumference. This diaphragm 7
Numeral 1 closes the outer peripheral side of the groove 33 of the support cylinder 30, and is curved in an arch shape so that the axial middle portion protrudes into the groove 24. Here, an annular space formed in the groove 33 whose outer peripheral side is closed by the diaphragm 71 is a sub liquid chamber 73. A diaphragm 7 is provided between the outer peripheral surface of the diaphragm 71 and the inner peripheral surface of the intermediate cylinder 69.
1 is an air chamber 75 capable of elastic deformation in the radial direction. The air chamber 75 is communicated with the outside of the device as needed.

The sub liquid chamber 73 and the pressure receiving liquid chamber 57 communicate with each other through a through hole 61 of the support cylinder 30, a groove 33 and a communication passage 59 of the support cylinder 30, and the through hole 61, the groove 33, and the communication hole. The passage 59 constitutes a restriction passage 77 as an orifice. Here, the pressure receiving liquid chamber 57,
Liquids such as water, oil, and ethylene glycol are filled and sealed in the sub liquid chamber 73 and the restriction passage 77.

In the vibration isolator 10 of the present embodiment, the rigidity of the diaphragm 71 forming a part of the partition wall of the sub liquid chamber 73 is set to a magnitude corresponding to the frequency of the shake vibration in the automobile, and the liquid in the restriction passage 77 is Is set to a magnitude corresponding to the frequency of the shake vibration.

An open end of a rubber diaphragm 79 formed in a cup shape near the lower end thereof is fixed to the inner peripheral surface of the connecting fitting 64 over the entire periphery by vulcanization bonding. The diaphragm 79 is arranged so as to project upward with its open end as the lower end. As a result, inside the diaphragm 79, a gas-filled chamber 81 is formed, which is a substantially cylindrical space whose lower surface is closed by the bottom plate of the outer cylindrical member 18. A circular opening 80 is formed in the top plate of the diaphragm 79 around the axis S.

A cup-shaped spring receiving member 83 is disposed in the gas filling chamber 81, and the top surface of the spring receiving member 83 is in close contact with the top plate of the diaphragm 79. The spring receiving member 83 has a through-hole 8 in its top plate along the axis S.
4 is formed, and a cylindrical wall 85 bent downward is formed on the outer peripheral portion. Here, a connection pin 87 that penetrates the center of the drive partition wall 53 and protrudes downward is inserted into the through hole 84 of the spring receiving member 83. Connecting pin 87 protruding into gas filling chamber 81 from through hole 84
A fixing ring 89 is caulked and fixed to the tip of the. Thus, the spring receiving member 83 is connected to the drive partition wall 53.

Here, on the upper surface side of the spring receiving member 83, a circular convex portion 86 is formed at the peripheral edge of the through hole 84. When the spring receiving member 83 is connected to the drive partition wall 53, the convex portion is formed. The top surface of 86 is in close contact with the lower surface of the rigid plate 54 of the drive partition wall 53. A diaphragm 79 is provided on the outer peripheral surface of the convex portion 86.
Of the opening 80 in the diaphragm 79 is compressed by being sandwiched between the top surface of the spring receiving member 83 and the lower surface of the rigid plate 54.

In the gas filling chamber 81, a metal coil spring 91 is disposed between the spring receiving member 83 and the bottom surface of the outer tube fitting 18. This coil spring 91 is
The center axis thereof substantially coincides with the axis S, and the lower end thereof is in pressure contact with the bottom surface of the outer sleeve 18 and the upper end thereof is a spring receiving member 83.
Is pressed against the inside of the wall portion 85, thereby being compressed in the axial direction by a predetermined amount.

The space formed between the outer peripheral surface of the diaphragm 79 and the inner peripheral surface of the connection fitting 65 is the same as that of the diaphragm 7.
9 is an air chamber 93 capable of being deformed in the radial direction, and the air chamber 93 is provided with a connecting fitting 93 and a lower cylindrical portion 22.
Is communicated to the outside by an air hole 95 penetrating through.

One end of a pressure pipe 97 is connected to the bottom plate of the outer cylinder 18 via a nipple (not shown) or the like, and the other end of the pressure pipe 97 is connected to a three-port two-position switching valve (hereinafter, switching valve). (Referred to as a valve) 99.

The switching valve 99 is connected to a pressure supply pipe 103 communicating with the intake manifold 101 of the engine and a pressure release pipe 105 communicating with the external space. The switching valve 99 is an electromagnetic opening / closing valve having a built-in electromagnetic solenoid. In an excited state where a driving voltage (for example, DC 12 V) is applied, the switching valve 99 communicates the pressure supply pipe 103 with the pressure pipe 97 and receives a driving voltage. In the non-excited state, the pressure release pipe 105 communicates with the pressure pipe 97.

Here, the intake manifold 101 is
When the engine is operating, the inside is always maintained at a negative pressure with respect to the atmospheric pressure. Therefore, when the drive voltage is applied to the switching valve 99, the gas filling chamber 81 communicates with the intake manifold 101, and the internal pressure of the gas filling chamber 81 becomes negative, and when the driving voltage is not applied to the switching valve 99, The gas filling chamber 81 communicates with the external space, and the internal pressure of the gas filling chamber 81 becomes equal to the atmospheric pressure.

In the vibration isolator 10, when the internal pressure of the gas filling chamber 81 changes from the atmospheric pressure to a negative pressure, the diaphragm 79 contracts downward in the axial direction, and the driving partition 53 is moved downward by the elastic ring 55 and the coil spring 91. Displace downward along the axial direction against the deformation resistance. Thereby, the elastic body 35
Is maintained in an undeformed state, the pressure receiving fluid chamber 57
And the pressure in the pressure receiving liquid chamber 57 decreases.

When the internal pressure of the gas filling chamber 81 changes from negative pressure to atmospheric pressure, the driving partition wall 53 is displaced upward in the axial direction by the elastic restoring force of the elastic ring 55 and the coil spring 91, and the driving partition wall is moved upward. A diaphragm 79 connected to 53 extends upward. As a result, if the elastic body 35 is kept in an undeformed state, the volume of the pressure receiving liquid chamber 57 is reduced and the liquid pressure in the pressure receiving liquid chamber 57 is increased. At this time, the drive partition wall 53 is moved above the initial position shown in FIG. 1 by the restoring force and the inertia force of the elastic ring 55 and the coil spring 99.

At this time, since the outer peripheral surface of the elastic ring 55 is fixed to the inner peripheral surface of the partition member 47 in the drive partition wall 53, it is a central portion excluding a part of the outer peripheral side of the elastic ring 46. The pressure receiving liquid chamber 5 is substantially formed by the pressurizing displacement portion 56.
It can be considered that the hydraulic pressure in 7 changes. The diameter of the pressure displacement portion 57 is smaller than the diameter of the entire drive partition 53,
And R becomes larger than the diameter of the rigid plate 54.

The vibration isolator 10 has a controller 107 for controlling the switching valve 99.
Is connected to a vibration sensor 109 installed on the vehicle body 12. The vibration sensor 109 is installed in the vicinity of the mounting portion of the engine 14 on the vehicle body 12, detects vibration of the vehicle body 12, and uses an electric signal of a waveform (for example, a sine waveform) corresponding to the vibration as a detection signal as a controller. Output to 107.

The controller 107 includes a vibration sensor 109
, The frequency and phase of the vibration in the vehicle body 12 are determined. In the vibration isolator 10 of the present embodiment, when the controller 107 determines that the vibration transmitted to the vehicle body 12 is idle vibration (20 to 50 Hz), the drive partition wall 53 is driven at a frequency equal to the vibration frequency of the vehicle body 12. The duty ratio of the drive voltage, that is, the ratio between the on-time for turning on the drive voltage to the switching valve 99 and the off-time for turning off the drive voltage so as to vibrate, is set. Further, the controller 107 adjusts the phase of the drive voltage so that the drive partition wall 53 vibrates at a phase that is different from the phase of the vibration in the vehicle body 12 by a predetermined time or at the same phase.

Next, the vibration isolator 10 according to the embodiment of the present invention will be described.
The operation of will be described.

When vibration from the engine is input to the vibration isolator 10, the vibration is transmitted to the elastic body 35, whereby the elastic body 35 is elastically deformed and the pressure receiving liquid chamber 57 expands and contracts.
As a result, the vibration is absorbed by the resistance based on the internal friction of the elastic body 35, and the liquid in the pressure receiving liquid chamber 57 moves back and forth between the auxiliary liquid chamber 73 through the restriction passage 77, and the liquid flows in the restriction passage 77. A large damping force is generated by resonance (liquid column resonance). As a result, shake vibration (less than 15 Hz), which is low-frequency vibration generated as the vehicle travels at a relatively high speed among engine vibrations, is effectively absorbed, and the vibration is transmitted to the vehicle body 12 side. It becomes difficult.

When the shake vibration is input, the switching valve 99 may be controlled so that the inside of the gas filled chamber 81 is in a negative pressure state with respect to the atmospheric pressure in order to prevent free vibration of the drive partition wall 53. .

On the other hand, in an idling state or a low-speed running state, the vibration frequency is higher than the
Idle vibration (20 to 50H)
z) is input to the vibration isolator 10. In this case, the controller 97 sets a duty ratio corresponding to the vibration frequency transmitted to the vehicle body 12, and turns on / off the drive voltage applied to the switching valve 99 according to the duty ratio. As a result, the drive partition wall 53 reciprocates (vibrates) in the same phase as the transmitted vibration or at a phase shifted by a predetermined time, so that an increase in the liquid pressure in the pressure receiving liquid chamber 77 can be suppressed.

That is, even when the restriction passage 77 is clogged due to the input of the idle vibration, the driving partition 53 is vibrated at a frequency equal to the vibration frequency, and the vibration phase of the driving partition 53 with respect to the phase of the transmission vibration is kept constant. Since the hydraulic pressure in the pressure receiving liquid chamber 57 can be suppressed from rising by shifting the time or in phase, the dynamic spring constant in the idle vibration region does not increase, and the vibration in the idle vibration region is reliably absorbed, and Vibration transmitted to the side 12 can be reduced.

Further, in the vibration isolator 10 of the present embodiment, the drive partition wall 53 is moved in the coil spring 9 along the volume expansion / contraction direction.
1 and a diaphragm 79 connected to the rigid plate 54 of the drive partition 53 is provided in the gas filled chamber 8.
The elastic ring 5 of the driving partition 53 is extended and contracted along the axial direction in accordance with a change in atmospheric pressure in the driving partition 1 to displace the driving partition.
It is not necessary to adjust the rigidity of the elastic ring 5 to set the amplitude of the drive partition wall 53 when the pressure is supplied to the gas sealing chamber 81, and the elastic ring 55 is formed of a low-rigidity rubber material to reduce the rigidity of the elastic ring 55. Therefore, the projected area (pressure receiving area) of the driving partition 55 along the axial direction of the elastic ring 55 can be reduced. As a result, the ratio of the pressure receiving area occupied by the rigid plate 54 in the drive partition wall 53 can be increased, and the area of the pressure displacement section 56 of the drive partition wall 53 can be made sufficiently large.
The fluid pressure in the inside can be changed efficiently.

Further, as compared with the case where the spring constant is set by the elastic ring 55, the spring constant can be easily set by the coil spring 91 and the spring constant can be set in a wide range.
The spring constant of the driving partition 53 can be made sufficiently small with respect to the magnitude of the negative pressure in 1, and the amplitude of the driving partition 53 when the pressure is supplied to the gas filled chamber 81 can be made sufficiently large.

Further, since the diaphragm 79 has a damping ability with respect to the vibration system, it is possible to prevent the occurrence of higher-order resonance in the drive partition wall 53. As a result, it is possible to prevent the vibration of the drive partition wall 53 from being disturbed by the influence of the higher-order resonance. For example, it is possible to smoothly vibrate the drive partition wall 53 along a sine waveform corresponding to the waveform of the vibration transmitted to the vehicle body 12. .

In the vibration isolator 10 of the present embodiment,
Although the structure in which the outer tube fitting 18 is attached to the vehicle body 12 is adopted, the structure in which the outer tube fitting 18 is attached to the engine side may be reversed. Also, the controller 107
The type of vibration transmitted to the vehicle body 12 is determined based on a detection signal from the vibration sensor 109, and the switching valve 99 is controlled. A crank signal corresponding to the engine speed is input to the controller 107, and the crank signal is input. May be caused to cause the controller 107 to control the switching valve 99.

Also, in the vibration isolator 10 of the present embodiment, the case has been described where an intake manifold which is maintained at a negative pressure state when the engine is operated is used as a pressure supply source. It is also possible to use the exhaust manifold of the engine as a pressure source, for example, as a pressure source.

(Second Embodiment) FIG. 3 shows a vibration isolator 210 according to a second embodiment. In FIG. 3, members having the same configuration and operation as those of the first embodiment described above with reference to FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted or simplified.

The vibration isolator 210 is provided with a cup-shaped lower mounting base 212 as a mounting member, on which mounting bolts 214 are erected. A flange portion 216 extending radially outward is formed at the upper end of the lower mounting base 212. The lower mounting base 212 is mounted on the vehicle body 12 of the automobile, and the lower mounting base 212 is connected and fixed to the vehicle body 12 by screwing the nut 220 into the mounting bolt 214.

On the other hand, the flange portion 21 of the lower mounting base 212
6, a flange portion 65 of a connection fitting 64 housed in the lower mounting base 212 is placed.
On flange 5, a flange portion 227 extending in the radial direction from the lower end of cylindrical support fitting 226 is mounted.

The driving partition 53 is provided on the inner peripheral side of the support fitting 226.
Are disposed, and the elastic ring 55 of the drive partition wall 53 is provided.
Are vulcanized and bonded to the inner peripheral surface of the support fitting 226 over the entire circumference. Further, the lower end of the diaphragm 79 is vulcanized and bonded to the inner peripheral surface of the connection fitting 64 over the entire circumference, similarly to the vibration isolator 10 according to the first embodiment.

On the upper side of the lower mounting base 212, the outer cylinder fitting 23 is provided.
8 are arranged coaxially. A tapered portion 239 whose inner and outer diameters increase toward the upper side is formed on the upper side of the outer cylindrical fitting 238, and an annular elastic body 240 is vulcanized on the inner peripheral surface of the tapered portion 239. Glued. A part of the elastic body 240 is thinly extended to near the lower end of the inner periphery of the outer metal fitting 238. Outer tube fitting 23
8 has a flange portion 242 extending radially outward.
The outer peripheral side of the flange portion 242 is caulked inward, and the outer cylinder fitting 238 and the lower mounting base 212 are fixed to each other. Further, between the flange portion 242 of the outer cylinder fitting 238 and the flange portion 216 of the lower mounting base 212, the flange portion 65 of the connection fitting 64 and the support fitting 2 are provided.
The thin-walled lower end of the elastic body 240 is sandwiched together with the 26 flanges 127 and is fixed respectively.

At the center of the elastic body 240, a fixing portion 244 formed in a cup shape in this example is disposed.
4 and the outer tube fitting 238 are integrally vulcanized and bonded by an elastic body 240.

A substantially hat-shaped air chamber forming portion 246 is provided above the fixing portion 244. A flange portion 248 provided at a lower end of the air chamber forming portion 246 is a flange portion of the fixing portion 244. The air chamber forming portion 246 is fixed to the fixing portion 244 by being placed on the upper portion 245 and the outer peripheral side of the flange portion 245 is caulked inward. A peripheral portion of the diaphragm 250, which is an elastic film made of rubber, is sandwiched between the fixing portion 244 and the air chamber forming portion 246.

The air chamber forming part 246 and the diaphragm 250
Is formed as an air chamber 252, and the inside thereof is communicated with outside air as needed. A mounting bolt 254 for mounting the engine is provided upright on the upper shaft core of the air chamber forming portion 246. An engine bracket (not shown) is mounted on the air chamber forming portion 246, and a nut is screwed into a mounting bolt 254 that penetrates the engine bracket. Linked to

The space between the fixing portion 244 and the diaphragm 250 is a sub-liquid chamber 260, and the space between the fixing portion 244 and the driving partition 53 is formed by connecting the elastic body 240 and the driving partition 53 to each other. The pressure receiving liquid chamber 262 is a part. A thin, cylindrical passage forming member 264 whose lower side is sealed is fitted and fixed inside the fixing portion 244, and a restriction passage 266 is formed on a lower outer peripheral side of the passage forming member 264. One end of the restriction passage 266 is connected to the pressure receiving liquid chamber 262, and the other end is connected to the sub liquid chamber 260. Therefore, the restriction passage 266 communicates the pressure receiving liquid chamber 262 with the sub liquid chamber 260. The inside of the pressure receiving liquid chamber 262 and the sub liquid chamber 260 is filled with a liquid such as ethylene glycol.

A diaphragm 79 gas-filled chamber 81 fixed to the inner peripheral surface of the connection fitting 64 is formed. Gas filled chamber 8
A dish-shaped spring receiving member 280 is disposed in 1, and the top surface of the spring receiving member 280 is in close contact with the top plate of the diaphragm 79. In the spring receiving member 280, a through hole 282 is formed in the top plate along the axis S, and the cylindrical wall portion 2 bent downward at the outer peripheral portion is formed.
84 are formed.

The driving partition 53 is provided in the opening 80 of the diaphragm 79 and the through hole 282 of the spring receiving member 280.
A connection pin 87 that penetrates through the center portion and protrudes downward is inserted. A fixing ring 89 is caulked and fixed to the distal end of the connecting pin 87 projecting from the through hole 282 into the gas sealing chamber 81. As a result, the spring receiving member 280 is
Linked to Further, the diaphragm 79 is connected to the spring receiving member 28.
0 and the driving partition wall 53 to be compressed in the axial direction.

The gas receiving chamber 81 has a spring receiving member 280 therein.
A metal coil spring 91 is arranged between the outer cylindrical fitting 18 and the bottom surface. This coil spring 91
Has its central axis substantially coinciding with the axis S, and its lower end presses against the bottom surface of the outer sleeve 18 and its upper end presses against the inside of the wall 284 of the spring receiving member 20. It is compressed in a predetermined direction.

The space formed between the outer peripheral surface of the diaphragm 79 and the inner peripheral surface of the connection fitting 65 is the same as that of the diaphragm 7.
9 is an air chamber 93 that can be deformed in the radial direction.
2 is communicated to the outside by an air hole 286 penetrating therethrough.

The anti-vibration device 210 according to the present embodiment also includes the controller 107 for controlling the switching valve 99 based on a signal from the vibration sensor 109.
07 performs basically the same control as the first embodiment on the switching valve 99. Therefore, the same operation and effect as those of the anti-vibration device 10 according to the first embodiment can also be obtained by the anti-vibration device 210.

[0073]

As described above, according to the vibration damping device of the present invention, the amplitude of the driving partition at the time of supplying pressure to the gas filled chamber is made sufficiently large, and the driving partition which changes the liquid pressure in the pressure receiving liquid chamber is provided. , The area of the pressure displacement portion can be increased.

[Brief description of the drawings]

FIG. 1 is a side sectional view of a vibration isolator according to a first embodiment of the present invention.

FIG. 2 is a perspective view showing a support cylinder and a partition member in the active damper according to the first embodiment of the present invention.

FIG. 3 is a side sectional view of an active damper according to a second embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Vibration isolator 12 Body (vibration receiving part) 18 Outer cylinder fitting (first mounting member) 39 Top plate fitting (second mounting member) 35 Elastic body 53 Drive partition 57 Pressure receiving liquid chamber 73 Sub liquid chamber 77 Restricted passage 79 Diaphragm (elastic film) 81 Gas filled chamber 99 Switching valve (pressure supply means) 101 Intake manifold (pressure supply source) 103 Pressure supply pipe (pressure supply path) 105 Pressure release pipe (pressure release path) 107 Controller (pressure supply means) 210 Vibration isolator 212 Lower mounting base (first mounting member) 240 Elastic body 246 Air chamber forming part 262 Pressure receiving liquid chamber

Claims (4)

[Claims] A first mounting member connected to one of the vibration generating unit and the vibration receiving unit; a second mounting member connected to the other of the vibration generating unit and the vibration receiving unit; and the first mounting An elastic body disposed between a member and the second mounting member; a pressure-receiving liquid chamber whose inner volume is expanded and contracted by deformation of the elastic body with the elastic body as a part of the partition; and a partition in the pressure-receiving liquid chamber. A drive partition wall which constitutes another part, and which can be displaced along a volume expansion / contraction direction of the pressure receiving liquid chamber by elastic deformation of a rubber portion provided on an outer peripheral portion; A spring member elastically supported along a direction, a gas filling chamber adjacent to the pressure receiving liquid chamber with the driving partition interposed therebetween, and a partition of the gas filling chamber, and connected to the driving partition, In accordance with the pressure change in the enclosure, An elastic film that expands and contracts to displace the drive partition wall; and a pressure supply unit that alternately communicates the gas-filled chamber with a pressure supply source that is set to a negative pressure or a positive pressure with respect to an external space and an external space. A vibration isolator characterized by the above-mentioned. 2. The pressure supply means alternately switches the communication destination of the gas filling chamber between a pressure supply source and an external space at a period corresponding to the vibration transmitted to the vibration receiving portion. 2. The vibration isolator according to 1. 3. The pressure supply means includes: a pressure supply path connected to an intake manifold of an engine using the gas-filled chamber as a pressure supply source; a pressure release path connected to the gas-filled chamber to an external space; 3. An anti-vibration device according to claim 1, further comprising an on-off valve for opening and closing the passage and the pressure release passage, respectively. 4. A sub-liquid chamber in which a part of the partition is formed of a diaphragm and in which a liquid is sealed and whose inner volume expands / contracts due to deformation of the diaphragm, and a restriction passage connecting the pressure-receiving liquid chamber to the sub-liquid chamber. The vibration isolator according to claim 1, 2, or 3, further comprising: