JPH04272533A - Vibrationproof device - Google Patents

Abstract

PURPOSE:To obtain a vibrationproof device which surely closes a restricting passage by an opening/closing member. CONSTITUTION:A main liquid chamber 28A and a subliquid chamber 28B are always connected through the second restricting passage 11 formed on a partitioning plate 30 and serve for absorbing the low frequency vibration, and the first restricting passage 36 absorbs the high frequency vibration. Since, when the low frequency vibration is generated, the cover bodies 34 and 38 are pressed to an upper plate 29, and the first restricting passage 36 is surely closed, even if each pressure in the main liquid chamber 28A and the subliquid chamber 28B rises. When the high frequency vibration is generated, a compressor 44 supplies the compressed air into a bag body 40, and the cover bodies 34 and 38 are separated from the upper plate 29, and the first restricting passage 36 is opened. Frequency of the vibration, and the passages 32 and 36 are selected to set each in the afore described described state.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibration isolating device used in automobile engine mounts, etc., for damping and absorbing vibrations from vibration generating parts.

0002

[Prior Art] In an automobile engine, a vibration isolating device as an engine mount is disposed between the engine and the vehicle body.
This prevents engine vibrations from being transmitted to the vehicle body.

[0003] Inside this vibration isolator, a main liquid chamber placed on the engine side and a sub liquid chamber placed on the vehicle body side are formed, and the main liquid chamber and the sub liquid chamber are filled with liquid. (Japanese Unexamined Patent Publication No. 61-55427). With this vibration isolator,
The main liquid chamber and the sub-liquid chamber are connected through a first restriction passage for absorbing shake vibrations and a second restriction passage for absorbing idle vibrations having a higher frequency than the shake vibrations, respectively. In this second restriction passage, an opening/closing member is provided in the sub-liquid chamber to bring the main liquid chamber and the sub-liquid chamber into communication and non-communication.

[0004] In the above-mentioned vibration isolator, when shake vibration occurs due to the vehicle being driven at high speed, the opening/closing member causes the second restricted passage to be in a disconnected state, that is, the first restricted passage is The liquid is allowed to flow back and forth between the main liquid chamber and the auxiliary liquid chamber through the chisel. Shake vibration is caused by liquid being the first
It is absorbed by the resistance or resonance of the liquid column when passing through the restricted passage. On the other hand, if idling vibration occurs due to the vehicle being stopped or running at a low speed of about 5 km/h, the first restricted passage becomes clogged, but the opening/closing member closes the second restricted passage. The restriction passage is brought into communication, and liquid flows back and forth between the main liquid chamber and the sub-liquid chamber through the second restriction passage. Therefore, idle vibrations are absorbed by the resistance or liquid column resonance when the liquid passes through the second restriction passage.

[0005]

In the above-mentioned vibration isolator, when shake vibration occurs, the opening/closing member closes the second restriction passage from the sub-liquid chamber side. By the way, as mentioned above, the main liquid chamber is arranged on the engine side as a vibration source. Therefore, due to vibration, a large pressure is applied from the main liquid chamber side to the auxiliary liquid chamber side, and the opening/closing member that closes the second restriction passage on the auxiliary liquid chamber side moves from the main liquid chamber side to the auxiliary liquid chamber side. receive great force towards Therefore, it is difficult to close the second restriction passage by the opening/closing member with sufficient reliability.

SUMMARY OF THE INVENTION In consideration of the above-mentioned facts, the present invention aims to provide a vibration isolating device that can reliably close a restriction passage by an opening/closing member.

[0007]

[Means for Solving the Problem] The invention of claim 1 provides a first member connected to one of a vibration generating section and a vibration receiving section, and a second member connected to the other of the vibration generating section and vibration receiving section. an elastic body that is provided between the first member and the second member and deforms when vibration occurs; a main liquid chamber that uses the elastic body as at least a part of a partition wall and is expandable and contractible; a sub-liquid chamber isolated from the liquid chamber; first and second restriction passages communicating the main liquid chamber and the sub-liquid chamber; and a peripheral edge of the opening of the second restriction passage provided within the main liquid chamber. an opening/closing member that can open and close a second restriction passage when pressed from the main liquid chamber side;
and a second state in which the second restriction passage is opened.

[0008] The invention according to claim 2 is characterized in that the first member is connected to one of the vibration generating section and the vibration receiving section, the second member is connected to the other of the vibration generating section and the vibration receiving section, and the first member is connected to the other of the vibration generating section and the vibration receiving section; an elastic body that is provided between the first member and the second member and deforms when vibration occurs; a main liquid chamber that is expandable and contractible using the elastic body as at least a part of a partition; and a main liquid chamber that is separated from the main liquid chamber. A sub-liquid chamber, first and second restriction passages that communicate the main liquid chamber and the sub-liquid chamber, and pressure from the main liquid chamber side to the opening periphery of the second restriction passage provided in the main liquid chamber. a first opening/closing member provided in the sub-liquid chamber and capable of opening and closing the second restriction passage; and a first opening/closing member that is provided in the sub-liquid chamber and is pressed from the sub-liquid chamber side to the opening periphery of the second restriction passage to open/close the second restriction passage. a second restriction passage provided between the first opening and closing member and the second opening and closing member, and a second restriction passage provided by the first and second opening and closing members depending on the magnitude of internal pressure; an expandable/contractable member capable of expanding and contracting between a first position where both ends of the second restriction passage are closed and a second position where both ends of the second restriction passage are opened by the first and second opening/closing members; and the vibration generating unit and pressure changing means for changing the pressure inside the expansion/contraction member according to the frequency of vibration caused by the expansion/contraction member.

[0009]

[Operation] In the vibration isolating device according to the invention of claim 1, when vibration is generated by the vibration generating section, the second
The opening/closing member is controlled to a first state in which the restriction passage is closed and a second state in which the second restriction passage is opened.

In the first state, liquid flows between the main liquid chamber and the auxiliary liquid chamber only through the first restricted passage. Therefore, the vibration generated by the vibration generator is absorbed by the resistance or liquid column resonance when the liquid passes through the first restriction passage. In this case, the liquid in the main liquid chamber exerts a large pressure from the main liquid chamber toward the auxiliary liquid chamber, but this pressure acts as a force to close the second restriction passage by the opening/closing member. Reliably closes the restricted passage. In the second state, liquid flows between the main liquid chamber and the sub liquid chamber through the second restriction passage. Therefore, the vibration generated by the vibration generating section is absorbed by the resistance when the liquid passes through the second restriction passage or by the liquid column resonance.

In the vibration isolating device according to the second aspect of the invention, when vibration is generated by the vibration generator, both ends of the second restriction passage are closed by the first and second opening/closing members depending on the frequency of the vibration. The pressure inside the expanding/contracting member is changed by the pressure changing means so that the first position is in which the expansion/contraction member is in the first position, and the second position is in which both ends of the second restriction passage are opened by the first and second opening/closing members.

In the first position, liquid flows between the main liquid chamber and the auxiliary liquid chamber only through the first restricted passage. Therefore, the vibration generated by the vibration generator is absorbed by the resistance or liquid column resonance when the liquid passes through the first restriction passage. In this case, the liquid in the main liquid chamber exerts a large pressure from the main liquid chamber toward the auxiliary liquid chamber, but this pressure acts as a force to close the second restriction passage by the opening/closing member. Reliably closes the restricted passage. Further, since the second restriction passage is closed from both sides of the main liquid chamber and the auxiliary liquid chamber by the first and second opening/closing members, the second restriction passage can be more reliably closed. In the second position, liquid flows between the main liquid chamber and the secondary liquid chamber through the second restricted passage. Therefore, the vibration generated by the vibration generating section is absorbed by the resistance when the liquid passes through the second restriction passage or by the liquid column resonance.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows a cross-sectional view of a vibration isolating device according to a first embodiment of the present invention. In the vibration isolator, a base plate 10 is fixed to a vehicle body (not shown).

A lower end portion of an outer plate 18 whose axis is perpendicular is caulked and fixed to a flange portion 10A extending from the periphery of the base plate 10. The outer periphery of rubber 20 is vulcanized and bonded to the inner periphery of the upper end of this outer plate 18 . A top plate 22 is provided at the upper center of the rubber 20. An automobile engine (not shown) is mounted on this top plate 22, and the engine is mounted on the top plate 22 with bolts 24 standing upright from the top plate 22. It is designed to be fixed to the

Outer plate 18 and base plate 1
The periphery of a diaphragm 26 is fixed between the diaphragm 26, the outer plate 18, and the rubber 20.
It is said that This liquid chamber 28 is filled with an incompressible liquid such as water or oil.

A partition plate 30 is provided inside the liquid chamber 28.
The liquid chamber 28 is divided by the partition plate 30, and a main liquid chamber 28A is arranged above and a sub liquid chamber 28B is arranged below. The partition plate 30 includes a cylindrical portion 31 having an upper plate 29 and a flange portion 33 extending radially outward from an end of the cylindrical portion 31 on the side opposite to the upper plate 29. This flange portion 33 is clamped and fixed between the diaphragm 26 and the outer plate 18.

A second restriction passage 36, which is a circular through hole, is provided approximately at the center of the cylindrical portion 31. The cylindrical part 31 has a thick wall near the connection part with the flange part 33, and the first restriction passage 11, which is a C-shaped gap in the longitudinal direction around the second restriction passage 36, is formed inside. First restricted passage 1
1 connects the main liquid chamber 28A through the opening 11A and the opening 11.
It communicates with the sub-liquid chamber 28B via B. therefore,
The first restriction passage 11 communicates the main liquid chamber 28A and the sub liquid chamber 28B.

A lid 34 serving as a first opening/closing member is disposed within the main liquid chamber 28A. The lid body 34 is formed into a cylindrical shape with a top plate 35. A through hole 35A is bored approximately in the center of the upper plate 35. Top plate 35 of lid body 34
The opposite side is open and forms an opening 34A.

A lid 38 serving as a second opening/closing member is disposed within the sub-liquid chamber 28B. The lid body 38 is formed into a cylindrical shape with a lower plate 39. A through hole 39A is bored approximately in the center of the lower plate 39. Lower plate 39 of lid body 38
The opposite side is open and forms an opening 38A.

[0020] A bag body 40 as an expandable member having an opening 41 is provided between the lid body 34 and the lid body 38. The bag body 40 is made of a stretchable material such as rubber. The bag body 40 is formed with a ring-shaped groove 40A on the opposite side to the opening 41 and a groove 40B on the opening 41 side. The groove 40A is in close contact with the inner wall of the through hole 35A and the peripheral edge of the through hole 35A of the upper plate 35, and the groove 40B is in close contact with the inner wall of the through hole 39A and the through hole 39 of the lower plate 39.
It is closely attached to the periphery of A. The lid body 34 and the lid body 38
is in the state shown in FIG. 1 when the bag 40 is contracted. In the state shown in FIG. 1, the lower end surface of the lid 34 is in close contact with the entire peripheral edge of the second restriction passage 36 of the upper plate 29 from above, and the main liquid chamber 28A side of the second restriction passage 36 is closed. Further, in the state shown in FIG. 1, the upper end surface of the lid 38 is brought into close contact with the entire peripheral edge of the second restriction passage 36 of the upper plate 29 from below, thereby closing the second restriction passage 36 on the side of the sub-liquid chamber 28. .

When the bag body 40 is inflated, the lower end surface of the lid body 34 and the upper end surface of the lid body 38 are separated from the upper plate 29.
The main liquid chamber 28A side of the second restriction passage 36 and the sub liquid chamber 28B
The side is open and the main liquid chamber 2 is opened through the second restriction passage 36.
8A and the sub-liquid chamber 28B are communicated with each other. One end of a pipe 42 serving as a passage for air supplied from the compressor 44 is attached to the opening 41 in close contact with the opening 42A. The pipe 42 is made of elastically deformable resin or the like, and the other end of the pipe 42 is connected to an air outlet (not shown) of a compressor 44. The middle part 42A of the pipe 42 is connected to the diaphragm 26 and the outer plate 1.
The inner wall of the through hole formed in 8 is in close contact with the inner wall of the through hole. The compressor 41 is connected to a control means 46 . The control means 46 controls the compressor 44 in accordance with the frequency of vibration of the engine so that the pressure inside the bag body 40 becomes a predetermined value. The compressor 44 is capable of lowering and increasing the pressure inside the bag 40, and allows the lid 34 and the lid 38 to be placed in the positions shown in FIGS. 1 and 2.

The operation of this embodiment will be explained below. When a vehicle travels at a high speed of, for example, 70 km/h or more, shake vibration occurs. The control means 46 determines whether the vibration is shake vibration or not. When it is determined that shake vibration is occurring, the lids 34 and 38 are placed in the state shown in FIG.
That is, the pressure inside the bag body 40 is lowered and the lid bodies 34, 3 are closed.
8, the compressor 41 is controlled so that the second restriction passage 36 is closed.

As a result, liquid is prevented from passing back and forth between the main liquid chamber 28A and the auxiliary liquid chamber 28B through the second restriction passage 36. Therefore, the liquid passes only through the first restriction passage 11 and flows back and forth between the main liquid chamber 28A and the sub liquid chamber 28B. Therefore, the shake vibration is effectively absorbed by the resistance when the liquid passes through the first restricted passage 11 or by the resonance of the liquid column. In the process of absorbing shake vibration, some liquid in the liquid chamber 28 alternately exerts a force from the main liquid chamber 28A side to the sub liquid chamber 28B side and a force from the sub liquid chamber 28B side to the main liquid chamber 28A side. receive. The force of the liquid directed from the main liquid chamber 28A to the auxiliary liquid chamber 28B acts on the upper plate 35 of the lid 34 to strengthen the closing force of the second restriction passage 36 by the lid. The restriction passage 36 can be reliably closed, and a mechanism for reliably closing it is not required. Further, a force is applied to the liquid from the side of the sub-liquid chamber 28B toward the side of the main liquid chamber 28A.
This acts to strengthen the closing force of the second restriction passage 36 by the lid body 38, so that the second restriction passage 36 can be reliably closed. Furthermore, in this embodiment, since the second restriction passage 36 is closed from both the main liquid chamber 28A side and the auxiliary liquid chamber 28B side, the second restriction passage 36 can be more reliably closed.

[0024] Also, when the engine is running at idle or when the vehicle speed is less than 5 km/h, idle vibration (20 to 3
0Hz) occurs. When idle vibration is occurring, the first restriction passage 11 is clogged. The control means 46 determines whether the vibration is idle vibration. When it is determined that idle vibration is occurring, the lid body 34,
38 is in the state shown in FIG.
The compressor 41 is controlled so that the pressure inside the compressor 0 is increased to release the second restriction passage 36 from being closed by the lids 34 and 38.

In the state shown in FIG. 2, the liquid flows through the second restricted passage 3.
6, it comes to go back and forth between the main liquid chamber 28A and the auxiliary liquid chamber 28B. Therefore, idle vibrations are effectively absorbed by the resistance when the liquid passes through the second restriction passage 36 or by liquid column resonance.

In the above embodiment, the bag body 4 is compressed by the compressor 44.
Although the pressure within 0 is changed, the negative intake pressure of the engine may also be used.

A second embodiment of the invention is shown in FIGS. 3 and 4. In the vibration isolator of the second embodiment, a lid 48 fixed to the upper plate 29 (FIG. 1) from below is used in place of the lid 39 of the first embodiment. The lid body 48 is attached to the lower plate 4
It is formed in a cylindrical shape with 7. The end surface of the lid body 48 opposite to the lower plate 47 is fixed from below to the peripheral edge of the second restriction passage 36 of the upper plate 29 (upside down is reversed from the state shown in FIG. 3). In this case, the lid 48 may be formed integrally with the upper plate 29.

A circular hole 47A is formed in the center of the lower plate 47, into which the groove 40B (FIG. 1) of the bag body 40 is tightly fitted, and a circular hole 47A is formed around the circular hole 47A along the circumferential direction of the lower plate 47. A plurality of long holes 47B are formed. Therefore, in this embodiment, when the lid body 34 opens the second restriction passage 36, liquid flows back and forth between the main liquid chamber 28A and the sub liquid chamber 28B via the elongated hole 47B.

The operation of the second embodiment will be explained below with reference to FIG. When the control means 46 determines that shake vibration is occurring, the lid 34 is moved to the state shown in FIG.
The compressor 44 is controlled so that the compressor 6 is in the closed state.

As a result, the liquid flows between the main liquid chamber 28A and the auxiliary liquid chamber 28B through only the first restricted passage 11. Therefore, the shake vibration is effectively absorbed by the resistance when the liquid passes through the first restricted passage 11 or by the resonance of the liquid column.

On the other hand, when the control means 46 determines that idle vibration is occurring, the lid 34 is moved upward in FIG. 1 to open the second restriction passage 36, that is, The compressor 44 is controlled so that the second restriction passage 36 is no longer closed by the lid 34 .

As a result, the liquid flows back and forth between the main liquid chamber 28A and the auxiliary liquid chamber 28B through the second restriction passage 36 and the elongated hole 47B. Therefore, idle vibrations are effectively absorbed by the resistance when the liquid passes through the second restriction passage 36 or by liquid column resonance. As described above, in this embodiment, the lid body 3
8 is fixed to the upper plate 29, the pipe 42 does not deform even if the states shown in FIGS. 1 and 2 are alternately repeated, so that the durability of the pipe 42 is improved. Furthermore, since the lid 48 is fixed, the amount of displacement of the lid 34 with respect to the upper plate 29 is reduced.

Next, a third embodiment of the present invention will be described with reference to FIG. As shown in FIG. 5, in the vibration isolator of this embodiment, the lower end portion of the outer plate 58 is fixed to a flange portion 50A that stands up from the periphery of the base plate 50 from above in the vertical direction of the vehicle body. A hollow portion 58A is formed inside the outer plate 58. The outer plate 58 has an enlarged diameter portion 58C in which the bottom of the hollow portion 58A is enlarged in inner diameter via a stepped portion 58B. A partition part 70 is inserted into the enlarged diameter part 58C from below the outer plate 58, and the base plate 50 is fixed to the lower surface of the outer plate 58, thereby fixing the partition member 70 to the outer plate 58. . A peripheral portion of the diaphragm 66 is sandwiched between the partition member 70 and the base plate 50.

The top of the hollow portion 58A of the outer plate 58 is a tapered surface whose inner diameter gradually increases upward, and the outer periphery of the rubber 60 is vulcanized and bonded to this tapered surface. This rubber 60 has an integrally extended and hanging extension part 60A arranged on the inner periphery of the hollow part 58A and the enlarged diameter part 58C.

A sleeve 64 is fixed through the rubber 60 at its center. A liquid chamber 68 is formed by the hollow part 58A of the outer plate 58, the rubber 60, and the diaphragm 66, and is filled with an incompressible liquid such as water or oil. It is an air chamber 67, and is communicated with outside air as necessary. The outer plate 58 is fixed to, for example, the body of an automobile, and the sleeve 64 is fixed to, for example, the engine of the automobile.

Furthermore, on the top of the outer plate 58,
Both ends 62A and 62B of the cover 62 are fixed to limit the maximum stroke of the sleeve 64.

A flange portion 70B extending outward is provided at the lower end of the partition member 70, and this flange portion 70B is clamped and fixed between the base plate 50 and the outer plate 58. Further, a rubber 60 is provided between the flange portion 70B of the partition member 70 and the outer plate 58.
The lower end edge 60C of is pinched.

A first restriction passage 74 is formed in the center of the partition member 70, and a lid 78 is brought into contact with the first restriction passage 74 from above the partition member 70. (the position indicated by the imaginary line in FIG. 5). Further, in the normal state, the lid body 78 is in the first position, so that the liquid chamber 68 is divided into the main liquid chamber 68A and the sub liquid chamber 68A.
It is divided into 8B. In this embodiment, the lid is not provided on the side of the sub-liquid chamber 68B, but only on the side of the main liquid chamber 68A.

The lid 78 is fixed to the tip of the drive shaft 52, and the drive shaft 52 is connected to the gearbox 54. A diaphragm 66 is fixed to the outer periphery of the gearbox 54 by vulcanization adhesive or the like, and the lower part of the gearbox 54 is fixed to the center of the base plate 50. Further, the gearbox 54 is connected to a motor 57 supported by a bracket 56 fixed to the lower center of the base plate 50.
The rotation of the motor 57 is converted into movement in the direction along the axis of the drive shaft 52.

Therefore, the motor 57 acts as a drive source and moves the drive shaft 52 in the direction along the axis, thereby bringing the lid body 78 into contact with and away from the first restriction passage 74, and moving the lid body 78 between the first position and the second position. (solid line position in FIG. 5), and when the lid 78 is in the second position, the lid 78 can be moved to the second position.
and the chamber wall of the main liquid chamber 68A (extended portion 60A of the rubber 60 of the hollow portion 58A of the outer plate 58) so that a gap 79 having an opening area wider than the opening area of the first restriction passage 74 is formed between It has become. In addition, the lid body 78 and the partition member 7
A seal member 72 is provided at the contact portion with 0,
This improves the sealing performance when the lid body 78 comes into contact with the partition member 70.

The partition member 70 has a ring groove 70C on the outer periphery.
is formed, and a ring-shaped orifice 51 is formed between it and the lower part 60B of the rubber 60. The orifice 51 has a C-shaped planar shape, and one end thereof communicates with the main liquid chamber 68A through a circular hole 53 formed adjacent to the first restriction passage 74 of the partition member 70. , the vicinity of the other end communicates with the sub-liquid chamber 68B via a circular hole 55 formed in the inner circumference of the ring groove 70C. Therefore, the orifice 51 has the role of a restriction passage that communicates the main liquid chamber 68A and the sub liquid chamber 68B.

Next, the operation of this embodiment will be explained. When the automobile engine attached to the sleeve 64 vibrates at a low frequency (set to less than 15 Hz in this embodiment), the liquid in the main liquid chamber 68A whose pressure increases due to this vibration passes through the orifice 51 to the sub liquid chamber 68B. When reaching the main liquid chamber 68A from the auxiliary liquid chamber 68B, or conversely, a damping effect based on viscous resistance and liquid column resonance occurs in the orifice 51, so that low frequency vibrations (shake vibrations) can be effectively absorbed. Can be done. In this case, a portion of the liquid in the liquid chamber 68 is moved from the main liquid chamber 68A side to the auxiliary liquid chamber 68B side by a force acting on the lid body 78, and the first restricted passage 74 by the lid body 78 is
Since the first restriction passage 74 acts to strengthen the closing force, the first restriction passage 74 can be reliably closed.

When the frequency of vibration of an automobile engine becomes high (20 to several 100 Hz), there is a possibility that the liquid in the orifice 51 becomes clogged. In this case, the motor 57 is driven, the drive shaft 52 is pushed up into the main liquid chamber 68A through the gear box 54, and the lid 78 is moved from the first position to the second position. It is separated from the first restriction passage 74 and communicates the main liquid chamber 68A and the sub-liquid chamber 68B via the first restriction passage 74. As a result, the liquid in the main liquid chamber 68A and the auxiliary liquid chamber 68B can flow through this first restriction passage 74, and the liquid near this first restriction passage 74 causes liquid column resonance, and vibrations are damped. Ru. Therefore, high-frequency vibrations that cause idle vibrations and muffled sounds can be absorbed.

In this embodiment, the lid 78 is provided only on the main liquid chamber side, but even if a force is applied to the liquid from the main liquid chamber 68A side toward the auxiliary liquid chamber 68B side due to vibration, the lid body Since it acts in the direction of strengthening the closing of the first restriction passage 74 by 78, the first restriction passage 74 can be reliably closed.

Next, a fourth embodiment of the present invention will be described with reference to FIG. Note that the same members as those in FIG. 5 are designated by the same reference numerals, and the description thereof will be omitted. One end of a wire 80 is connected to the end of the drive shaft 52 opposite to the valve body 78, and the other end of the wire 80 is connected to a piston 84 that reciprocates within the cylinder 82. A portion of the wire 80 near the connecting portion with the drive shaft 52 is inserted into a substantially L-shaped guide tube 86 fixed to the base plate 50 . The other end of a coil spring 88, one end of which is fixed to the cylinder 82, is connected to the surface of the piston 84 opposite to the wire 80. A pipe line 90 is connected to the cylinder 82 . Control means (not shown) is configured to apply engine suction negative pressure to the cylinder 82 via the pipe 90 when the frequency of the automobile engine is low, and to cut off the application of suction negative pressure when the engine frequency becomes high. controlled by With this suction negative pressure applied, the first restriction passage 74 is closed by the valve body 78, and with the suction negative pressure blocked, the valve body 78 is moved toward the main liquid chamber 68 side by the biasing force of the coil spring 88. The first restricted passage 74 is opened.

Next, the operation of this embodiment will be explained. When the automobile engine vibrates at a low frequency (set to less than 15 Hz in this example), the liquid in the main liquid chamber 68A passes through the orifice 51 to the auxiliary liquid chamber 68B, or conversely from the auxiliary liquid chamber 68B. Orifice 5 when reaching the main liquid chamber 68A
1, a damping effect based on viscous resistance and liquid column resonance occurs, so low frequency vibrations (shake vibrations) can be effectively absorbed. In this case, the first restriction passage 74 is closed because the valve body 78 is brought into close contact with the partition member 70 due to the suction negative pressure of the engine.

When the frequency of vibration of an automobile engine becomes high (20 to several 100 Hz), there is a possibility that the liquid in the orifice 51 becomes clogged. In this case, the application of negative suction pressure from the engine to the cylinder 82 is cut off under control by a control means (not shown), and the biasing force of the coil spring 88 pushes up the drive shaft 52 into the main liquid chamber 68A, causing the lid 78 to move into the main liquid chamber. Moved to 68A side. As a result, the first restriction passage 74 is opened, and the main liquid chamber 68A and the sub liquid chamber 68B are brought into communication via the first restriction passage 74. Therefore, the liquid in the main liquid chamber 68A and the auxiliary liquid chamber 68B can flow through this first restriction passage 74, and the liquid near this first restriction passage 74 causes liquid column resonance, and vibrations are damped. Ru. Therefore, high-frequency vibrations that cause idle vibrations and muffled sounds can be absorbed.

[0048]

Effect of the invention: As explained above, claims 1 and 2
According to the present invention, since the opening/closing member capable of opening and closing the second restriction passage is provided on the main liquid chamber side, it is possible to obtain a vibration isolating device in which the second restriction passage can be reliably closed by the opening/closing member. Has excellent effects.

[Brief explanation of the drawing]

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

FIG. 2 is an operational diagram of FIG. 1;

FIG. 3 is a perspective view showing a lid of a vibration isolator according to a second embodiment of the present invention.

FIG. 4 is a sectional view of the lid shown in FIG. 3;

FIG. 5 is a sectional view of a vibration isolator according to a third embodiment of the present invention.

FIG. 6 is a sectional view of a vibration isolator according to a fourth embodiment of the present invention.

[Explanation of symbols]

10 Base plate 11 Second restricted passage 20 Rubber 22 Top plate 30 Partition plate 34 Lid body 36 Second restricted passage 38 Lid body 40 Bag body 44 Compressor 46 Control means

Claims (2)

[Claims] 1. A first member connected to one of the vibration generating section and the vibration receiving section, a second member connected to the other of the vibration generating section and the vibration receiving section, and a first member connected to the first member and the first member connected to the other of the vibration generating section and the vibration receiving section. an elastic body that is provided between the second member and deforms when vibration occurs; a main liquid chamber that is expandable and contractible using the elastic body as at least a part of the partition wall; and a sub-liquid chamber that is isolated from the main liquid chamber. First and second restriction passages that communicate the main liquid chamber and the auxiliary liquid chamber; an opening/closing member capable of opening and closing the restriction passage;
A control means for controlling the opening/closing member to a first state in which the second restriction passage is closed and a second state in which the second restriction passage is opened according to the frequency of vibration by the vibration generation unit. Anti-vibration device with. 2. A first member connected to one of the vibration generating section and the vibration receiving section, a second member connected to the other of the vibration generating section and the vibration receiving section, and a second member connected to the first member and the vibration receiving section. an elastic body that is provided between the second member and deforms when vibration occurs; a main liquid chamber that is expandable and contractible using the elastic body as at least a part of the partition wall; and a sub-liquid chamber that is isolated from the main liquid chamber. First and second restriction passages that communicate the main liquid chamber and the auxiliary liquid chamber; a first opening/closing member capable of opening and closing the restriction passage; and a second opening/closing member provided in the sub-liquid chamber and capable of opening/closing the second restriction passage by being pressed from the sub-liquid chamber side to the periphery of the opening of the second restriction passage. an opening/closing member; a first opening/closing member provided between the first opening/closing member and the second opening/closing member;
and a first position where both ends of the second restriction passage are closed by the second opening and closing member; and a second position where both ends of the second restriction passage are closed by the second opening and closing member;
an expandable/contractable member that can be expanded/contracted to a second position where both ends of the restriction passage are open; and a pressure changing means that changes the pressure inside the expandable/contractable member in accordance with the frequency of vibration generated by the vibration generating section. Anti-vibration device with.