JP4409661B2 - Vibration isolator - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a vibration isolator that prevents transmission of vibration from a member that generates vibration, and is applicable to, for example, prevention of transmission of vibration from an engine mounted on a vehicle.
[0002]
[Prior art]
For example, an anti-vibration device as an engine mount is disposed between an engine of a vehicle that is a vibration generating unit and a vehicle body that is a vibration receiving unit, and the anti-vibration device absorbs vibration generated by the engine, Such a structure is known that prevents the transmission of the vehicle to the vehicle body side.
That is, as an example of this vibration isolator, not only the inner cylinder is disposed inside the cylindrical outer cylinder, but also the main liquid chamber and the auxiliary liquid chamber are provided inside the outer cylinder, and an orifice is provided. There is a bush type structure in which these liquid chambers communicate with each other through a restriction passage. When the mounted engine is activated and vibration is generated, it absorbs vibration or attenuates vibration as a low dynamic spring by liquid column resonance of the liquid in the restriction passage communicating with these liquid chambers. Therefore, the transmission of vibration is blocked.
[0003]
On the other hand, the engine speed changes widely with changes in the vehicle state, and the vibration frequency becomes wide in accordance with the wide operating state of the engine. Accordingly, in recent years, a vibration isolator having an orifice, which is a restricted passage having various lengths and inner diameters, has been devised in order to maintain a vibration isolating characteristic in each of vibrations in a wide range of frequencies. It was.
[0004]
Furthermore, these conventional vibration isolators generally have a structure in which one orifice is provided for each vehicle state, and a rotor that is a valve is rotatably provided, so that idling vibration is generated. In addition, the orifice can be switched between two modes at the time of traveling in which a middle / low-speed booming noise is generated. That is, the opening of the rotor serving as a switching valve is arranged so as to face one end side of each orifice, and the orifices are opened and closed by rotating the rotor.
[0005]
[Problems to be solved by the invention]
On the other hand, since the idling speed changes due to the use of a cooler or the like, the trend of recent design concepts of vehicles such as automobiles tends to be demanded to reduce vibrations in a wider range of frequencies. From the switching structure, it has become possible to consider a structure capable of switching three or more stages.
[0006]
However, if the three or more orifices are simply opened and closed sequentially with a rotor that simply rotates, the rotational angle of the rotor may increase and the switching sensitivity may decrease. That is, in a structure in which the number of orifices is simply increased and the rotor is moved in response to the vibration frequency, it is predicted that the response speed will deteriorate when switching from one mode to another. In particular, when the vehicle state is switched from the idling state to the traveling state, it is required to increase the switching speed, but it is difficult to obtain a sufficient response speed corresponding to this.
[0007]
In view of the above fact, the present invention aims to provide a vibration isolator capable of improving the switching sensitivity of the orifice even as a switching structure of three or more modes, and particularly when the vehicle state is switched from the idling state to the traveling state. An object of the present invention is to provide a vibration isolator capable of improving the switching sensitivity of an orifice by increasing the switching speed of a valve.
[0008]
[Means for Solving the Problems]
  The vibration isolator according to claim 1 includes 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 these An elastic body that is arranged between the mounting members and can be elastically deformed, a main liquid chamber in which liquid is sealed with the elastic body as a part of the partition wall, and an internal volume is changed by deformation of the elastic body, and liquid is sealed,and,At least part of the bulkheadBy the first diaphragmFormed elastically deformableFirstA secondary liquid chamber;A shake orifice for always communicating the main liquid chamber and the first sub-liquid chamber;Main liquid chamber andFirstA first orifice capable of reducing vibration by communicating with the sub liquid chamber, a main liquid chamber,SecondA second orifice communicating with the secondary liquid chamber and having one end disposed adjacent to one end of the first orifice and capable of reducing vibration at a frequency higher than a vibration frequency that the first orifice can reduce; RoomFirstA third orifice capable of reducing vibration at a frequency different from the vibration frequency that the first orifice and the second orifice can reduce by communicating between the first liquid chamber and the secondary liquid chamber;
these1st to 3rdThe three orifices are arranged so as to face each other and selectively open and close as they are rotated, so that vibrations at three different frequencies can be reduced., One through hole is formed in the cylindrical partA valve and an actuator for rotating the valve in a direction that opens the second orifice immediately after opening the first orifice;With
The space between the second diaphragm and the inner peripheral surface of the outer cylinder fitting in the second sub liquid chamber in which the liquid is sealed and a part of the partition wall is elastically deformable by the second diaphragm The second air chamber is filled with gas, and the passages for the first and third orifices are provided in parallel with the intermediate block, and a hole for the second orifice is provided in the intermediate block. The circular hole is provided on the opposite side of the passage.
[0009]
The operation of the vibration isolator according to claim 1 will be described below.
For example, when vibration in a medium frequency range is transmitted from the vibration generating unit connected to either the first mounting member or the second mounting member, the elastic body is deformed and the vibration is attenuated by the elastic body. Is done.
Furthermore, the internal volume of the main liquid chamber changes due to the deformation of the elastic body. At this time, the second and third orifices of the three orifices connecting the main liquid chamber and the sub liquid chamber are closed by a valve. With this state, the liquid does not flow into the closed orifice, but the liquid actively flows to the sub liquid chamber side by the opened first orifice. As a result, a pressure change occurs in the liquid in the opened first orifice, and accordingly, the partition wall of the sub liquid chamber formed to be elastically deformable is deformed.
[0010]
That is, when vibration in a medium frequency range is transmitted from the vibration generating unit side, the absolute spring is connected not only by the elastic body but also by the first orifice that connects the main liquid chamber and the sub liquid chamber and is opened by the valve. Is reduced, the vibration in the middle frequency range is absorbed, and the vibration is hardly transmitted to the vibration receiving portion side.
On the other hand, the vibration frequency is changed, and the above-described open first orifice generates vibration in which vibration in a high frequency range that cannot reduce vibration is connected to either the first mounting member or the second mounting member. Even when transmitted from the part side, the internal volume of the main liquid chamber changes due to the deformation of the elastic body as described above.
[0011]
At this time, the actuator rotates the valve in accordance with the frequency of vibration to open the second orifice connecting the main liquid chamber and the sub liquid chamber, thereby changing the internal volume of the main liquid chamber. Then, a pressure change occurs in the liquid in the newly opened second orifice, and accordingly, the partition wall of the sub liquid chamber formed to be elastically deformable is deformed. As a result, even when vibration in the high frequency range is transmitted from the vibration generating part side, the absolute spring is lowered by the second orifice opened by the valve in the same manner as described above, so that the vibration in the high frequency range is absorbed. It becomes difficult for vibration to be transmitted to the receiving side.
[0012]
Further, the vibration frequency changes, and vibrations in a frequency range that cannot be reduced by the first and second orifices, such as vibrations having a frequency lower than the vibration frequency that can be reduced by the first orifice, or vibrations that can be reduced by the second orifice. Even when vibration having a frequency higher than the frequency is transmitted from the vibration generating unit side, the elastic body is deformed and the actuator rotates the valve to open the third orifice in the same manner as described above. The absolute spring is lowered by the three orifices, so that the vibration in this frequency range is absorbed and the vibration is hardly transmitted to the vibration receiving portion side.
[0013]
From the above, in accordance with the rotation of the valve, which is disposed opposite to one end of each of these three orifices that can reduce vibration by communicating between the main liquid chamber and the sub liquid chamber, These three orifices are selectively opened and closed, and accordingly, vibrations at three different frequencies can be reduced. As a result, vibrations are appropriately absorbed at any vibration frequency, and a wide range of vibrations can be reduced.
[0014]
At this time, since the actuator rotates the valve in the direction in which the second orifice is opened immediately after opening the first orifice, the valve is rotated and the three orifices are sequentially opened and closed. The rotation angle becomes larger than necessary and the switching sensitivity does not decrease, and the switching sensitivity of the orifice can be maintained well.
[0015]
The operation of the vibration isolator according to claim 2 will be described below.
The present invention operates in the same manner as in the first aspect, but further, the third orifice is configured to reduce the vibration at a frequency lower than the vibration frequency that the first orifice can reduce, and the third orifice is opened. Since one end of the orifice is arranged so that the first orifice is opened immediately afterward, for example, low idle vibration and high idle vibration that occur during idling can be reduced while improving the switching sensitivity of the orifice.
[0016]
The operation of the vibration isolator according to claim 3 will be described below.
The present invention operates in the same manner as in the first and second aspects, but further, the third orifice is capable of reducing vibrations at two different frequencies from each other, and the third orifice on the low frequency side and the high frequency side can be reduced. Since the third orifice is opened in order of the third orifice on the low frequency side, the third orifice on the high frequency side, and the first orifice in this order, vibrations in a wider range are reduced while improving the switching sensitivity of the orifice. become able to.
[0017]
  According to a fourth aspect of the present invention, a vibration isolator is disposed between the first attachment member connected to one of the engine and the vehicle body, the second attachment member connected to the other of the engine and the vehicle body, and elastically disposed between these attachment members. A deformable elastic body, a main liquid chamber in which liquid is sealed with the elastic body as a part of the partition wall and the internal volume is changed by deformation of the elastic body, and liquid is sealed,and,At least part of the bulkhead, According to the first diaphragmAnd elastically deformableFirstA secondary liquid chamber;A shake orifice for always communicating the main liquid chamber and the first sub-liquid chamber;Main liquid chamber andFirstA first orifice capable of reducing high idle vibration by communicating with the secondary liquid chamber, a main liquid chamber,SecondA second orifice that communicates with the secondary liquid chamber and that has one end disposed adjacent to one end of the first orifice and that can reduce vibration during traveling at a frequency higher than the vibration frequency that the first orifice can reduce. And the main liquid chamberFirstA third orifice that is capable of reducing low idle vibrations that are lower in frequency than the vibration frequency that the first orifice can reduce by communicating with the secondary liquid chamber;1st to 3rdThe three orifices are arranged so as to face each other and selectively open and close as they are rotated, so that vibrations at three different frequencies can be reduced., One through hole is formed in the cylindrical partA valve and an actuator for rotating the valve in a direction that opens the second orifice immediately after opening the first orifice;With,The space between the second diaphragm and the inner peripheral surface of the outer cylinder fitting in the second sub liquid chamber in which the liquid is sealed and a part of the partition wall is elastically deformable by the second diaphragm The second air chamber is filled with gas, and the passages for the first and third orifices are provided in parallel with the intermediate block, and a hole for the second orifice is provided in the intermediate block. The circular hole is provided on the opposite side of the passage.
[0018]
  The operation of the vibration isolator according to claim 4 will be described below. In this claim, the same effect as in claim 1 is obtained. However, in this claim,1st to 3rdThese three orifices are selectively opened and closed by a valve rotated by an actuator, so that low idle vibration, high idle vibration and vibration during traveling can be reduced.
[0019]
In other words, when the vibration generator is an engine and the vibration receiver is a vehicle body, the actuator rotates the valve and selectively opens and closes the three orifices. The first orifice reduces certain high idle vibrations, the second orifice reduces vibrations during running, which are vibrations in the high frequency range, and further, low orifice vibrations, which are low frequency range vibrations generated during idling, in the third orifice. Was reduced. As a result, similarly to the first aspect, the vibration is appropriately absorbed at any vibration frequency, and a wide range of vibration can be reduced.
[0020]
At this time, since the actuator rotates the valve in the direction in which the second orifice is opened immediately after opening the first orifice, the valve is rotated and the three orifices are sequentially opened and closed. The rotation angle becomes larger than necessary and the switching sensitivity does not decrease, and the switching sensitivity of the orifice can be maintained well when the vibration frequency is changed from high idle vibration to vibration during traveling. .
[0021]
The operation of the vibration isolator according to claim 5 will be described below.
The present invention operates in the same manner as the fourth aspect, but further, since the first orifice is opened immediately after the third orifice that reduces the vibration at a frequency lower than the vibration frequency that the first orifice can reduce is opened. The low idle vibration and the high idle vibration can be reduced while improving the switching sensitivity of the orifice.
[0022]
The operation of the vibration isolator according to claim 6 will be described below.
In this claim, the same action as in claim 4 and claim 5 is performed, but in this claim, as in claim 3, a wider range of vibrations can be reduced while improving the switching sensitivity of the orifice. .
[0023]
DETAILED DESCRIPTION OF THE INVENTION
A first embodiment of a vibration isolator according to the present invention is shown in FIG. 1 to FIG. 5, and the present embodiment will be described based on these drawings.
As shown in FIGS. 1 and 2, the so-called bush type vibration isolator 10 is provided with a mounting frame 12 formed in a ring shape for connection to a vehicle body (not shown). Is fitted with a cylindrical outer tube fitting 16. The outer peripheral portion of the rubber-made thin first diaphragm 20 is vulcanized and bonded to the metal bracket 14, and the first diaphragm 20 is closer to the upper portion in FIGS. 1 and 2 on the inner peripheral surface side of the outer tube fitting 16. Has been placed. Further, as shown in FIGS. 1 and 2, a first air chamber 31 is provided between the first diaphragm 20 and the outer tube fitting 16, and communicates with the outside as necessary.
[0024]
The intermediate cylinder 22 and the intermediate block 24 are inserted into the outer cylinder fitting 16, and the intermediate cylinder 22 and the intermediate block 24 constitute a partition member.
The intermediate block 24 is formed in a substantially semicircular block shape when viewed from the axial direction of the outer cylinder fitting 16, and the outer peripheral surface of the intermediate block 24 is formed on the inner circumference surface of the outer cylinder fitting 16 as shown in FIG. 1. It is in close contact. As shown in FIG. 2, flange portions 22A are formed at both axial ends of the intermediate tube 22, and the intermediate block 24 is inserted between the pair of flange portions 22A. Further, the outer peripheral surfaces of the pair of flange portions 22A are in close contact with the inner peripheral surface of the outer tube fitting 16.
[0025]
As shown in FIGS. 1 and 2, a portion of the intermediate cylinder 22 that faces the flat surface portion 24 </ b> B serving as the upper surface of the intermediate block 24 is a cavity, and an inner cylinder fitting 26 that is connected to an engine (not shown) in the cavity. Has penetrated. The inner cylinder fitting 26 is arranged in parallel with the outer cylinder fitting 16, and an elastic body 28 formed of a rubber material or the like is suspended between the inner cylinder fitting 26 and the intermediate cylinder 22. As a result, the inner cylinder fitting 26 can be moved relative to the outer cylinder fitting 16.
That is, the inner cylinder fitting 26 connected to the engine that is the vibration generating portion serves as the first attachment member, and the outer cylinder fitting 16 that is connected to the vehicle body that is the vibration receiving portion via the attachment frame 12 is the second attachment member. It is made a member.
[0026]
Further, the elastic body 28 is also extended to the outer peripheral surface between the flange portions 22A of the intermediate cylinder 22, and protrudes from both end portions of the intermediate block 24 to the inner peripheral arc on the inner peripheral side of the portion formed in an arc shape. A part of the elastic body 28 is in close contact with the surface 24A. In addition, a cutout portion 28A is formed in the middle portion of the elastic body 28 and below the inner cylindrical metal fitting 26 so as to dent the lower surface of the elastic body 28. The cutout portion 28A and the intermediate block 24 are The space between them is a main liquid chamber 30.
[0027]
On the other hand, a first sub-liquid chamber 32 surrounded by the intermediate cylinder 22 and the first diaphragm 20 is formed between the pair of flange portions 22 </ b> A of the intermediate cylinder 22. Further, as shown in FIG. 5, a groove portion 46 is formed in a U shape on the outer peripheral surface of the intermediate block 24. One end of the groove 46 opens to the right end of the intermediate block 24 in FIG. 1 and is connected to the first sub liquid chamber 32. The other end of the groove 46 communicates with the main liquid chamber 30 through a through hole 48 formed through the intermediate block 24. And these groove part 46 and through-hole 48 become the shake orifice 64 as a restriction | limiting channel | path for shake vibration absorption.
[0028]
Further, a circular hole 34 is formed on the flat portion 24B side of the intermediate block 24, and a circular shape that has a smaller diameter than the circular hole 34 and penetrates the outer peripheral surface of the intermediate block 24 at the bottom of the circular hole 34. A through hole 35 is formed coaxially with the circular hole 34. Further, a counterbore portion 39 is provided coaxially with the circular through-hole 35 on the outer cylindrical metal fitting 16 side of the intermediate block 24, and a sealing O-ring 41 is fitted on the outer side of the counterbore portion 39. Yes.
[0029]
A rotor 36 that is a valve is rotatably inserted into the circular hole 34 and the circular through hole 35. The main liquid chamber 30 side of the rotor 36 is a cylindrical cylindrical portion 36A, and a thin shaft portion 36B as a rotating shaft is provided coaxially with the cylindrical portion 36A on the opposite side of the cylindrical portion 36A. Yes. Further, a cover plate 40 that also serves as a washer is fixed to the flat portion 24B side of the intermediate block 24 to prevent the rotor 36 from coming off.
[0030]
In addition, a pair of O-rings 44 are fitted on the outer periphery of the thin shaft portion 36B. Accordingly, the liquid does not leak out of the intermediate block 24 through the circular through hole 35 by the O-ring 44. Furthermore, a through-hole 38 is formed in the cylindrical portion 36A of the rotor 36 to communicate the inside and outside of the cylindrical portion 36A. On the other hand, a passage 56 and a passage 57 are formed in the intermediate block 24 so that one end sides thereof are respectively connected to the circular holes 34 and extend in parallel with each other in the direction perpendicular to the paper surface in FIG. ing. That is, one end of each of the passage 56 and the passage 57 is opened on the inner periphery of the circular hole 34. The cross-sectional area of the passage 57 is formed larger than the cross-sectional area of the passage 56, and the liquid passage resistance of the passage 57 is smaller than the passage resistance of the passage 56.
[0031]
As shown in FIGS. 4 and 5, the other end of the passage 56 communicates with one end of a passage 58 that is a groove formed in the outer periphery of the intermediate block 24 along the circumferential direction. Is communicated with the first auxiliary liquid chamber 32. Accordingly, when the rotor 36 rotates and the through hole 38 faces the passage 56 as shown in FIG. 3A, the passages 56 and 58 provide a space between the main liquid chamber 30 and the first sub liquid chamber 32. It will be communicated. That is, the passages 56 and 58 allow the main liquid chamber 30 and the first sub-liquid chamber 32 to communicate with each other and serve as a low idle vibration absorbing restriction passage that is a low frequency vibration among the idle vibrations. An idle orifice 60 is formed.
[0032]
As shown in FIGS. 4 and 5, the other end of the passage 57 is also communicated with one end of the passage 58 in the same manner as described above. Accordingly, when the rotor 36 rotates and the through hole 38 faces the passage 57 as shown in FIG. 3B, the passage between the main liquid chamber 30 and the first sub liquid chamber 32 is caused by the passages 57 and 58. It will be communicated.
That is, the passages 57 and 58 allow the main liquid chamber 30 and the first sub-liquid chamber 32 to communicate with each other and serve as a restriction passage for absorbing high idle vibration that is vibration on the high frequency side even in idle vibration. The idle orifice 61 is configured, and accordingly, the passage 58 is a passage shared by the low idle orifice 60 and the high idle orifice 61.
[0033]
On the other hand, as shown in FIG. 1, the intermediate block 24 further has a hole 92 for burial along the radial direction of the circular hole 34 and in the opposite direction to the passages 56, 57. Is formed. A second sub-liquid chamber 96 having an arcuate space is formed in the portion of the intermediate block 24 corresponding to the opening end of the hole 92 for the hole. The second auxiliary liquid chamber 96 is opened. Accordingly, when the rotor 36 is rotated and the through hole 38 faces the hole 92 for volume as shown in FIGS. 1 and 3C, the space between the main liquid chamber 30 and the second sub liquid chamber 96 is set. Will be communicated.
In other words, the main liquid chamber 30 and the second sub liquid chamber 96 are communicated with each other through the hole 92 for the hole formed so as to be shorter than the passages 56 and 57 so as to absorb high-frequency vibration. The orifice 62 for a construction used as a restriction passage for absorbing the medium-low speed construction sound which is the vibration of the frequency is constituted.
[0034]
As described above, the high idle orifice 61 is the first orifice, and the massing orifice 62 is the second orifice that can reduce vibration during traveling at a frequency higher than the vibration frequency reduced by the first orifice. Is the third orifice. In addition, although one end of the high idle orifice 61, the bulk orifice 62, and the low idle orifice 60 is arranged to face the rotor 36, one end of the bulk orifice 62 is one end of the high idle orifice 61 in FIG. Is disposed adjacent to the downstream side in the direction of arrow R.
[0035]
A rubber-made thin second diaphragm 94 is sandwiched between the outer tube fitting 16 and the intermediate block 24 at the outer peripheral portion of the intermediate block 24 with respect to the second auxiliary liquid chamber 96. The second diaphragm 94 is an elastically deformable partition wall of the second sub liquid chamber 96. For this reason, the space between the second diaphragm 94 and the inner peripheral surface side of the outer cylinder fitting 16 is a second air chamber 98 built in the outer cylinder fitting 16 and filled with gas inside. Two air chambers 98 allow the second diaphragm 94 to be deformed.
[0036]
Therefore, the second diaphragm 94 constitutes a part of the partition wall of the second sub-liquid chamber 96, and the area of the second diaphragm 94 is the partition wall of the first sub-liquid chamber 32 as shown in FIG. The area of the first diaphragm 20 constituting a part of the first diaphragm 20 is smaller, and the thickness of the second diaphragm 94 is substantially equal to that of the first diaphragm 20, so that the second diaphragm 94 is higher in rigidity than the first diaphragm 20. become. The main liquid chamber 30, the first sub liquid chamber 32, and the second sub liquid chamber 96 are sealed so as to be filled with a liquid such as ethylene glycol.
[0037]
On the other hand, on the outside of the mounting frame 12, a motor 70 is disposed as an actuator that rotates only in one predetermined direction. The distal end of the rotating shaft 71 of the motor 70 is fitted into the distal end side of the thin shaft portion 36 </ b> B of the rotor 36. Further, the motor 70 is provided with a flange portion 70 </ b> A, and the flange portion 70 </ b> A is formed in an arc shape along the outer diameter of the mounting frame 12. For this reason, a screw (not shown) inserted through the flange portion 70 </ b> A is screwed into a screw portion (not shown) provided on the attachment frame 12, whereby the motor 70 is fixed to the attachment frame 12.
[0038]
With the above structure, when the rotor 36 is rotated by the motor 70 and the through hole 38 of the cylindrical portion 36A opens the low idle orifice 60 as shown in FIG. The main liquid chamber 30 and the first sub liquid chamber 32 communicate with each other. Further, from this position, when the rotor 36 is rotated 120 ° in the direction of arrow R by the motor 70 and the through hole 38 of the cylindrical portion 36A opens the high idle orifice 61 as shown in FIG. The main liquid chamber 30 and the first sub liquid chamber 32 communicate with each other through 61. Further, from this position, the rotor 36 is rotated 120 ° in the direction of arrow R by the motor 70, and when the through hole 38 of the cylindrical portion 36A opens the squeezing orifice 62 as shown in FIG. The main liquid chamber 30 and the second sub liquid chamber 96 communicate with each other through 62.
[0039]
Then, when the rotor 36 is further rotated 120 ° in the direction of arrow R by the motor 70 from this position, the low idle orifice 60 is opened again as described above, and thereafter the orifices are sequentially opened as described above. Will be. Therefore, these orifices 60, so that low idle vibration that is low frequency vibration, high idle vibration that is medium frequency vibration, and vibration during traveling that is high frequency vibration can be reduced. The rotor 36 opens and closes 61 and 62 to switch the orifice.
[0040]
As described above, the rotor 36 moves between the main liquid chamber 30 and the first sub liquid chamber 32 via the low idle orifice 60 or the high idle orifice 61 as shown in FIGS. 3 (A) and 3 (B). As shown in FIG. 3C, the motor is selectively arranged between the main liquid chamber 30 and the second sub liquid chamber 96 via the squeezing orifice 62 as shown in FIG. The rotor 36 is rotated by 70.
[0041]
The motor 70 is connected to a controller 72 which is a control means, and its rotation is controlled by the controller 72. The controller 72 is operated by the vehicle power supply, can receive at least detection signals from the vehicle speed sensor 74 and the engine speed detection sensor 76, detect the vehicle speed and the engine speed, and can determine whether idle vibration or shake vibration has occurred. Therefore, it is possible to determine whether the generated idle vibration is low idle vibration or high idle vibration.
[0042]
Next, the operation of the present embodiment will be described.
When the engine mounted on the vibration isolator 10 is connected to the inner cylinder fitting 26, the vibration of the engine is transmitted to the elastic body 28 via the inner cylinder fitting 26. The elastic body 28 acts as a vibration absorbing main body and can absorb vibrations by a vibration damping function based on the internal friction of the elastic body 28.
Further, the liquid in the main liquid chamber 30 and the first sub liquid chamber 32 whose internal volumes change with deformation of the elastic body 28 and the first diaphragm 20 is shaken orifice 64, high idle orifice 61 or low idle orifice 60. The liquid in the main liquid chamber 30 and the second sub liquid chamber 96 in which the internal volume changes with deformation of the elastic body 28 and the second diaphragm 94 is retained. The vibration isolation effect can be improved by the damping action based on the viscous resistance of the liquid flow generated in the orifice space and the liquid column resonance.
[0043]
In addition to the shake orifice 64 that is always open, a low idle orifice 60, a high idle orifice 61, and a closing orifice 62 are provided. As a result of providing the rotor 36 for switching the passage, the following operation is performed.
[0044]
For example, when the engine is idling or when the vehicle speed is 5 km / h or less, low idle vibration (about 25 Hz) occurs. The controller 72 not only determines whether or not idle vibration is generated by the vehicle speed sensor 74 and the engine speed detection sensor 76, but also determines whether the generated idle vibration is low idle vibration or high idle vibration.
When the controller 72 determines that the idle vibration is occurring and determines that the low idle vibration is occurring, the controller 72 rotates the motor 70 to cause the through hole 38 of the rotor 36 to pass through the low hole 38 as shown in FIG. The arrangement is made to correspond to the idle orifice 60 and not to correspond to the high idle orifice 61 and the massing orifice 62.
[0045]
As a result, the high idle orifice 61 and the bulk orifice 62 are closed, and the liquid passes between the main liquid chamber 30 and the first sub liquid chamber 32 via the low idle orifice 60 having a small cross-sectional area and a large liquid passage resistance. In this low idle orifice 60, the liquid column resonates and the absolute spring, which is the dynamic spring constant, decreases, and the low idle vibration is absorbed.
[0046]
On the other hand, when a cooler or the like is used when the engine is in idling operation, the engine speed during idling changes, and high idle vibration (about 45 Hz), which is vibration on the high frequency side, occurs among idle vibrations. The controller 72 not only determines whether or not idle vibration is generated by the vehicle speed sensor 74 and the engine speed detection sensor 76, but also determines whether the generated idle vibration is low idle vibration or high idle vibration.
When the controller 72 determines that the idle vibration is occurring and determines that the high idle vibration is occurring, the controller 72 rotates the motor 70 to set the through hole 38 of the rotor 36 to the high position as shown in FIG. The arrangement is made to correspond to the idle orifice 61 and not to correspond to the low idle orifice 60 and the massing orifice 62.
[0047]
As a result, the low idle orifice 60 and the bulk orifice 62 are closed, and the liquid passes between the main liquid chamber 30 and the first sub liquid chamber 32 via the high idle orifice 61 having a large cross-sectional area and a small liquid passage resistance. In this high idle orifice 61, the liquid column resonates and the absolute spring is lowered to absorb the high idle vibration.
[0048]
On the other hand, when the vehicle travels at a high speed of, for example, 70 to 80 km / h or more, shake vibration (about 10 Hz) occurs. The controller 72 determines whether or not the shake vibration is generated by the vehicle speed sensor 74 and the engine speed detection sensor 76. If the controller 72 determines that the shake vibration has occurred, the controller 72 operates the motor 70 to rotate the rotor 36, and as shown in FIG. The low idle orifice 60 and the high idle orifice 61 are arranged so as not to correspond to each other.
[0049]
As a result, the low idle orifice 60 and the high idle orifice 61 are closed, the normally open shake orifice 64 communicates the main liquid chamber 30 and the first sub liquid chamber 32, and the bulk orifice 62 is the main liquid chamber. 30 and the second auxiliary liquid chamber 96 communicate with each other. As a result, a pressure change based on the engine vibration generated in the main liquid chamber 30 is transmitted to the liquid in the shake orifice 64 and the squeeze orifice 62, and the resistance of the liquid is received to absorb the shake vibration.
Furthermore, for medium and low speed booming noise (about 80 Hz), which is a high-frequency and small-amplitude vibration that may occur with shake vibration, the liquid spring resonates in the short-length boom orifice 62 and the absolute spring is lowered. This booming sound is absorbed.
[0050]
As described above, the rotor 36 disposed to face one end of the three orifices 60, 61, 62 that can communicate with the main liquid chamber 30 and the sub liquid chambers 32, 96 to reduce vibrations is provided in the motor. The three orifices 60, 61, and 62 are selectively opened and closed as they are rotated by the actuator 70, and accordingly, vibrations at three different frequencies can be reduced. became. As a result, vibrations are appropriately absorbed at any vibration frequency, and a wide range of vibrations can be reduced.
[0051]
At this time, since the motor 70 rotates the rotor 36 in the direction in which the opening orifice 62 is opened immediately after opening the high idle orifice 61, the rotor 36 is rotated to open and close the three orifices in sequence. Even in the structure, the rotation angle of the rotor 36 does not increase and the switching speed does not decrease, and the switching sensitivity of the orifice can be maintained well.
Further, the low idle orifice 60 is configured to reduce the vibration at a frequency lower than the vibration frequency that the high idle orifice 61 can reduce, so that the high idle orifice 61 is opened immediately after the low idle orifice 60 is opened. Since one end of the orifice is arranged in the low-idle vibration and the high-idle vibration generated during idling, the orifice switching sensitivity can be reduced and improved.
[0052]
Next, FIG. 6 shows a second embodiment of the vibration isolator according to the present invention, and this embodiment will be described based on this figure. In addition, the same code | symbol is attached | subjected to the member same as the member demonstrated in 1st Embodiment, and the overlapping description is abbreviate | omitted.
As shown in FIG. 6, the present embodiment has a structure in which one more orifice that is opened and closed by the through hole 38 of the rotor 36 is added to the intermediate block 24. That is, the length between the low idle orifice 60 and the high idle orifice 61 is the same as that of the two orifices 60, 61 and is larger than the cross-sectional area of the low idle orifice 60. A middle idle orifice 63 having a cross-sectional area smaller than 61 is disposed, and the orifice is switched in four stages.
[0053]
One end of the middle idle orifice 63 is opened in the circular hole 34 while being positioned between one end of the low idle orifice 60 and one end of the high idle orifice 61. The other end of the middle idle orifice 63 is also communicated with the first sub liquid chamber 32, for example.
As a result, in the present embodiment, the third orifice is composed of a pair of orifices that can reduce vibrations at two different frequencies. Specifically, the low idle orifice 60 for absorbing the low idle vibration that is the low frequency side vibration among the idle vibrations is the third orifice on the low frequency side. The middle idle orifice 63 for absorbing the middle idle vibration, which is a vibration, is the third orifice on the high frequency side, so that the third orifice is formed by the third orifice on the low frequency side and the third orifice on the high frequency side. Will be composed.
[0054]
As described above, this embodiment can also obtain the same characteristics as those of the first embodiment. Furthermore, in the present embodiment, the respective orifices are sequentially opened by rotating the rotor 36 by 90 ° in the order of (A), (B), (C), and (D) of FIG. 6 according to the vehicle state. Is done.
That is, since the low idle orifice 60, the middle idle orifice 63, the high idle orifice 61, and the orifice for massing 62 are sequentially opened in order, so that a wider range of vibration can be reduced while improving the switching sensitivity of the orifice. Become.
[0055]
Further, as a structure for switching the orifices in four stages, for example, there may be a configuration in which the idle orifice has two stages, a low idle orifice and a high idle orifice, and the traveling orifice has two stages, that is, a low-speed traveling orifice and a high-frequency orifice. In this case as well, if the low idle orifice, the high idle orifice, the low-speed moving traveling orifice, and the high-frequency traveling orifice are sequentially opened in this order, a wider range of vibrations can be reduced while improving the switching sensitivity of the orifice. It becomes like this.
[0056]
In the above embodiment, the outer cylinder fitting 16 side is attached to the vehicle body, and the inner cylinder fitting 26 side is attached to the engine. However, the reverse arrangement may be adopted, and the auxiliary liquid chamber is the first auxiliary liquid. Two chambers and a second sub-liquid chamber are provided, but one sub-liquid chamber may be used. Furthermore, in the above-described embodiment, the structure in which the orifice is switched in three stages and the structure in which the orifice is switched in four stages have been described as examples.
On the other hand, in the above embodiment, the purpose is to isolate the engine mounted on the vehicle, but it goes without saying that the anti-vibration device of the present invention can be used for other purposes as well as the shape and the like. It is not limited to the thing of the form.
On the other hand, in the above embodiment, the rotor is rotated by the motor. However, the present invention is not limited to this, and the actuator for rotating the rotor may be other than the motor, and the valve body is a valve other than the rotor. Etc. may be used.
[0057]
【The invention's effect】
As a result of the configuration described above, the vibration isolator of the present invention can improve the switching sensitivity of the orifice even in a switching structure of three or more modes, and in particular, the vehicle state is changed from the idling state to the traveling state. When switching, it is possible to improve the switching sensitivity of the orifice by increasing the switching speed of the valve.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a first embodiment of a vibration isolator according to the present invention.
FIG. 2 is a view taken along line 2-2 in FIG.
FIG. 3 is a view showing the relationship between the through hole and the orifice of the rotor of the first embodiment of the vibration isolator according to the present invention, wherein (A) shows a state where the low idle orifice is opened; B) shows a state in which the high idle orifice is opened, and (C) shows a state in which the squeeze orifice is opened.
FIG. 4 is an exploded perspective view of an intermediate block and a rotor applied to the first embodiment of the vibration isolator according to the present invention.
5A and 5B are diagrams showing an intermediate block applied to the first embodiment of the vibration isolator according to the present invention, in which FIG. 5A is a left side view, and FIG. 5B is a bottom view; (C) is a right side view.
FIG. 6 is a diagram showing a relationship between a through hole and an orifice of a rotor of a second embodiment of a vibration isolator according to the present invention, wherein (A) shows a state where a low idle orifice is opened; (B) shows a state in which the middle idle orifice is opened, (C) shows a state in which the high idle orifice is opened, and (D) shows a state in which the squeeze orifice is opened.
[Explanation of symbols]
10 Vibration isolator
16 Outer tube bracket
26 Inner tube bracket
28 Elastic body
30 Main liquid chamber
32 First sub-liquid chamber
36 rotor
60 Low idle orifice
61 High idle orifice
62 Orifice for cedar
70 motor
96 Second secondary liquid chamber

Claims (6)

A first attachment member coupled to one of the vibration generator and the vibration receiver;
A second attachment member coupled to the other of the vibration generating portion and the vibration receiving portion;
An elastic body arranged between these mounting members and capable of elastic deformation;
A main liquid chamber in which liquid is sealed with the elastic body as a part of the partition wall and the internal volume changes due to deformation of the elastic body;
A first sub-liquid chamber in which a liquid is enclosed , and at least a part of the partition wall is formed to be elastically deformable by the first diaphragm (20) ;
A shake orifice (64) for always communicating the main liquid chamber and the first sub liquid chamber;
A first orifice (61) capable of reducing vibration by communicating between the main liquid chamber and the first sub liquid chamber;
A vibration frequency that allows communication between the main liquid chamber and the second sub liquid chamber (96) and that one end is disposed adjacent to one end of the first orifice (61) and the first orifice (61) can be reduced. A second orifice (62) that can reduce higher frequency vibrations;
The main liquid chamber and the first of the first orifice (61) communicates between the auxiliary liquid chamber and the second third orifice orifice (62) is capable of reducing the vibration of a frequency different from the frequency of vibration can be reduced ( 60)
These three first to three orifices are arranged so as to face each other and selectively open and close as the three orifices are rotated to generate vibrations at three different frequencies. A valve (36) in which one through hole (38) is formed in the cylindrical portion (36A), each of which can be reduced;
An actuator (70) for rotating the valve (36) in a direction that opens the second orifice (62) immediately after opening the first orifice (61) ;
The second diaphragm (94) and the inner periphery of the outer tube fitting (16) of the second sub-liquid chamber in which the liquid is sealed and a part of the partition wall is elastically deformable by the second diaphragm (94) The space between the surfaces is a second air chamber (98) in which gas is sealed.
The passages (57, 56) for the first and third orifices (61, 60) are provided in parallel with the intermediate block (24), and the hole for the second orifice (62) is filled ( 92) is provided on the opposite side of the passage (57, 56) across the circular hole (34) of the intermediate block (24) .  One end of the third orifice is arranged in an arrangement in which the first orifice is opened immediately after the third orifice is opened so that the vibration at a frequency lower than the vibration frequency that can be reduced by the first orifice is reduced. The vibration isolator according to claim 1, wherein:  The third orifice is a pair of orifices that can reduce vibrations at two different frequencies, and the third orifice on the high frequency side is opened immediately after the third orifice on the low frequency side is opened. 3. The vibration isolator according to claim 2, wherein one end of the third orifice is disposed so that the first orifice can be opened immediately after the third orifice on the frequency side is opened. A first attachment member coupled to one of the engine and the vehicle body;
A second attachment member coupled to the other of the engine and the vehicle body;
An elastic body arranged between these mounting members and capable of elastic deformation;
A main liquid chamber in which liquid is sealed with the elastic body as a part of the partition wall and the internal volume changes due to deformation of the elastic body;
Liquid is sealed, and, at least a portion of the partition wall, the first auxiliary liquid chamber which is elastically deformable formed by the first diaphragm (20),
A shake orifice (64) for always communicating the main liquid chamber and the first sub liquid chamber;
A first orifice (61) capable of reducing high idle vibration by communicating between the main liquid chamber and the first sub liquid chamber;
The main liquid chamber and the second sub liquid chamber (96) communicate with each other and one end is disposed adjacent to one end of the first orifice (61) , and the first orifice has a frequency higher than the vibration frequency that can be reduced. A second orifice (62) that can reduce vibration during traveling,
A third orifice (60) that can communicate between the main liquid chamber and the first sub-liquid chamber to reduce low idle vibration at a frequency lower than the vibration frequency that the first orifice (61) can reduce;
These three first to three orifices are arranged so as to face each other and selectively open and close as the three orifices are rotated to generate vibrations at three different frequencies. A valve (36) in which one through hole (38) is formed in the cylindrical portion (36A), each of which can be reduced;
Comprising an actuator (70) to rotate the valve (36) in a direction in which the order to open the second orifice (62) immediately after opening the first orifice (61),
The second diaphragm (94) and the inner periphery of the outer tube fitting (16) of the second sub-liquid chamber in which the liquid is sealed and a part of the partition wall is elastically deformable by the second diaphragm (94) The space between the surfaces is a second air chamber (98) in which gas is sealed.
The passages (57, 56) for the first and third orifices (61, 60) are provided in parallel with the intermediate block (24), and the hole for the second orifice (62) is filled ( 92) is provided on the opposite side of the passage (57, 56) across the circular hole (34) of the intermediate block (24) .  5. The vibration isolator according to claim 4, wherein one end of the third orifice is arranged in an arrangement in which the first orifice is opened immediately after the third orifice is opened.  The third orifice is a pair of orifices that can reduce vibrations at two different frequencies, and the third orifice on the high frequency side is opened immediately after the third orifice on the low frequency side is opened. 6. The vibration isolator according to claim 5, wherein one end of the third orifice is arranged so that the first orifice can be opened immediately after the third orifice on the frequency side is opened.

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