JPH04228945A - Vibration isolation device - Google Patents

Abstract

PURPOSE:To absorb vibrations over a wide range of frequencies. CONSTITUTION:A main liquid chamber 28, a first sub-liquid chamber 46 and a second sub-liquid chamber 48 are arranged in an outer cylinder 16, and the main liquid chamber 28 and the first sub-liquid chamber 46 are connected to each other via a shake orifice 30. Also, the main liquid chamber 28 and the second subliquid chamber 48 are connected to each other via an idle orifice 32. A pipe 52 is connected to an air chamber 43 corresponding to the diaphragm 44 of the second sub-liquid chamber 48, and further connected to an intake manifold 70 via an electromagnetic valve 56. At the time of a shaking vibration, the electromagnetic valve 56 is opened and the air is drawn from the air chamber 43 by the negative pressure of the intake manifold 70. The diaphragm 44 is thereby made to adhere to the outer cylinder 16 for making the expansion or contraction of the second sub-liquid chamber 46 impossible. Liquid moves only in the shake orifice 30 and absorbs a shaking vibration. At the time of an idling vibration, the shake orifice 30 is clogged and, therefore, the electromagnetic valve 56 is closed to expand the diaphragm 44, thereby enabling the second sub-liquid chamber 46 to expand and contract. Also, the liquid is caused to move in the idle orifice 32, thereby absorbing the idling vibration.

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 vehicles, general industrial machinery, etc., which absorbs and damps vibrations from vibration generating parts.

0002

[Prior Art] A vibration isolating device serving as an engine mount is disposed between the engine and the vehicle body in an automobile engine.
It is designed to prevent engine vibrations from being transmitted to the vehicle body.

A plurality of small liquid chambers filled with liquid are formed inside this vibration isolating device, and these small liquid chambers communicate with each other through restricted passages. When engine vibration is transmitted to the vibration isolator, the vibration is absorbed by the passage resistance and liquid column resonance when the liquid filled in one small liquid chamber moves through the restriction passage to the other small liquid chamber. It is now possible to do so.

By the way, the vibrations generated in the engine include the so-called shake vibration that occurs when the vehicle is running at high speed, and the so-called idling vibration that occurs when the vehicle is idling or when the vehicle is running at about 5 km/h. etc.

Generally, the shake vibration has a frequency of 15
While the frequency of idle vibration is less than 20 Hz,
The frequency is 40Hz, and the shake vibration and idle vibration have different frequencies.

However, conventional vibration isolators are effective only when the frequency of generated vibrations is within a predetermined range determined by the opening area and length of the restricted passage, and cannot effectively attenuate vibrations at frequencies outside of this predetermined range. It cannot be absorbed.

For this reason, with conventional vibration isolators, if the vibration isolator is adjusted to effectively damp shake vibrations, it becomes difficult to effectively damp idle vibrations, and it is difficult to effectively damp idle vibrations. Adjusting the vibration isolator makes it difficult to effectively damp shake vibrations.

[0008]

SUMMARY OF THE INVENTION In view of the above-mentioned facts, it is an object of the present invention to provide a vibration isolating device capable of attenuating and absorbing vibrations over a wide range of frequencies.

[0009]

[Means for Solving the Problem] A vibration isolator according to claim 1 has an outer cylinder connected to one of a vibration generating part and a vibration receiving part, and an inner cylinder connected to the other of the vibration generating part and a vibration receiving part. tube and
an elastic body that is provided between the outer cylinder and the inner cylinder and deforms when vibration occurs; a main liquid chamber that can be expanded and contracted using the elastic body as part of a partition wall; and a main liquid chamber that is arranged inside the outer cylinder. a first sub-liquid chamber; a first restriction passage arranged inside the outer cylinder and connecting the main liquid chamber and the first sub-liquid chamber; a first restriction passage arranged inside the outer cylinder and connected to the main liquid chamber; a second restriction passage communicating with the chamber; a second sub-liquid chamber disposed inside the outer cylinder and provided in a part of the second restriction passage; and a second sub-liquid chamber arranged inside the outer cylinder and provided in a part of the second restriction passage A diaphragm constituting the partition wall of the second sub-liquid chamber is disposed inside the outer cylinder and on the opposite side of the diaphragm from the second sub-liquid chamber side, and the diaphragm is arranged inside the outer cylinder when the inside becomes negative pressure. It is characterized by comprising an air chamber that is brought into close contact with a wall surface to prevent movement of the diaphragm and substantially disappear, and negative pressure means that makes the inside of the air chamber negative pressure.

The vibration isolator according to a second aspect of the invention is the vibration isolator according to the first aspect, in which the diaphragm is an elastic body provided on the inner circumferential surface of the outer cylinder and connects the outer cylinder and the inner cylinder. It is characterized by being made up of parts.

[0011] The vibration isolator according to claim 3 is the vibration isolator according to claim 1 or 2, characterized in that the diaphragm is composed only of an elastic body.

[0012] The vibration isolator according to claim 4 is the vibration isolator according to any one of claims 1, 2, and 3, in which the diaphragm moves toward the second sub-liquid chamber side in a free state. The inner wall surface of the air chamber facing the diaphragm has a convex R-shaped cross section, and has a shape that is substantially symmetrical to the shape of the diaphragm, with a plane of symmetry between the second sub-liquid chamber and the air chamber. It is said that

[0013] The vibration isolator according to claim 5 includes a first member connected to one of the vibration generating section and the vibration receiving section, and a second member 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 can be expanded and contracted using the elastic body as part of a partition wall; and a main liquid chamber that is isolated from the main liquid chamber. a partition member that isolates the main liquid chamber and the first sub-liquid chamber; and a first sub-liquid chamber formed in the partition member that communicates the main liquid chamber and the first sub-liquid chamber. a second restriction passage formed in the partition member and communicating with the main liquid chamber; a second auxiliary liquid chamber provided in a part of the second restriction passage; and a second auxiliary liquid chamber. A diaphragm constituting a partition wall of the chamber, and a diaphragm disposed inside the outer cylinder and on the opposite side of the diaphragm from the second sub-liquid chamber side, so that the diaphragm is tightly attached to the inner wall surface when the inside is made negative pressure. The present invention is characterized in that it includes an air chamber that prevents the movement of the diaphragm and substantially disappears, and a negative pressure means that makes the inside of the air chamber negative pressure.

The vibration isolator according to claim 6 is characterized in that, in the vibration isolator according to claim 5, the air chamber is provided in either the first member or the second member. .

[0015] A vibration isolator according to a seventh aspect of the present invention is the vibration isolator according to the fifth aspect, characterized in that the air chamber is provided outside the first member and the second member.

[0016]

[Function] According to the vibration isolating device according to claim 1, when the inner cylinder is connected to the vibration generation source and the outer cylinder is connected to the vibration receiving part, the vibration is received through the inner cylinder, the elastic body, and the outer cylinder. Supported by the department. At this time, vibrations are absorbed not only by resistance based on internal friction of the elastic body but also by passage resistance or liquid column resonance of the liquid flowing through the first restriction passage or the second restriction passage. When the frequency of vibration is less than a predetermined frequency, the inside of the air chamber is made to have a negative pressure by the negative pressure means, and the diaphragm constituting the partition of the second sub-liquid chamber formed in the second restriction passage is pressed against the inner wall of the air chamber. Fix tightly. As a result, the air chamber substantially disappears, and the second sub-liquid chamber cannot expand or contract. For this reason,
The liquid does not flow through the second restriction passage, and no resistance to passage of the liquid within the second restriction passage occurs. As a result, the liquid
Vibrations below a predetermined frequency are absorbed by the resistance and resonance of the liquid column when the liquid flows through the first restriction passage and passes through the first restriction passage. Further, when the frequency of vibration is higher than a predetermined frequency, the inside of the air chamber is not made negative pressure by the negative pressure means. Therefore, the diaphragm is separated from the inner wall of the air chamber and becomes elastically deformable, allowing the second sub-liquid chamber to expand and contract. As a result, the liquid flows through the second restriction passage, and vibrations in a predetermined frequency range are absorbed by liquid column resonance when the liquid passes through the second restriction passage.

According to the second aspect of the vibration isolating device, the diaphragm is formed of a part of an elastic body provided on the inner peripheral surface of the outer cylinder and connecting the outer cylinder and the inner cylinder. Therefore, there is no need to separately form and assemble a diaphragm, resulting in a reduction in the number of parts.

According to the vibration isolating device according to the third aspect, since the diaphragm is composed of only an elastic body, the rigidity can be lowered compared to a diaphragm provided with a fiber layer or the like. This makes the diaphragm easier to deform,
When the air chamber is brought into negative pressure, it can reliably come into close contact with the inner wall of the air chamber.

According to the vibration isolating device according to the fourth aspect, the diaphragm has a convex cross section toward the second sub-liquid chamber in a free state, and the inner wall surface of the air chamber facing the diaphragm is
The shape is substantially symmetrical to the shape of the diaphragm with a plane of symmetry between the second sub-liquid chamber and the air chamber. Therefore, when the air chamber is brought into negative pressure, the diaphragm can be reversed toward the air chamber and can be convex toward the air chamber. Furthermore, since the shape of the inner wall surface of the air chamber is approximately the shape of a diaphragm, the diaphragm can be securely brought into close contact with the inner wall.

According to the vibration isolating device according to the fifth aspect, when the first member is connected to the vibration generating source and the second member is connected to the vibration receiving portion, the vibration is caused by the first member, the elastic body, It is supported by the vibration receiver via the second member. At this time, vibrations are absorbed not only by resistance based on internal friction of the elastic body but also by passage resistance or liquid column resonance of the liquid flowing through the first restriction passage or the second restriction passage. When the frequency of vibration is less than a predetermined frequency, the inside of the air chamber is made to have a negative pressure by the negative pressure means, and the diaphragm constituting the partition of the second sub-liquid chamber formed in the second restriction passage is pressed against the inner wall of the air chamber. Fix tightly. As a result, the air chamber substantially disappears, and the second sub-liquid chamber cannot expand or contract. Therefore, the liquid does not flow through the second restriction passage, and no resistance to passage of the liquid in the second restriction passage occurs. As a result, the liquid flows through the first restricted passage and into the first restricted passage.
Vibrations below a predetermined frequency are absorbed by the resistance and resonance of the liquid column when passing through the restricted passage.

According to the vibration isolating device according to the sixth aspect of the present invention, the air chamber is provided in either the first member or the second member. Therefore, the air chamber can be formed by a part of the first member or the second member, resulting in a reduction in the number of parts.

According to the vibration isolating device according to the seventh aspect, the air chamber is provided outside the first member and the second member. Therefore, there is no risk of complicating the inside of the vibration isolator, and the degree of freedom in designing the internal structure increases.

[0023]

[Embodiment] [First Embodiment] FIGS. 1 to 4 show a first embodiment of a vibration isolating device 10 according to the present invention.

FIG. 4 shows an exploded perspective view of a so-called bush type vibration isolator 10. As shown in FIG.

A cylindrical outer cylinder 16 is disposed coaxially with the substantially cylindrical inner cylinder 12 . In this embodiment, the inner cylinder 1
2 is connected to an engine 76 (see FIG. 1) as a vibration generating section via a bracket (not shown), and the outer cylinder 16 is connected to a vehicle body (not shown) as a vibration receiving section via a bracket 17 (see FIG. 1). It looks like this.

[0026] An outer cylinder 1 is provided between the inner cylinder 12 and the outer cylinder 16.
An intermediate cylinder 18 is disposed coaxially with the cylinder 6. Ring-shaped large diameter portions 18A and 18B are formed at both axial ends of the intermediate cylinder 18. Further, the axially intermediate portion of the intermediate cylinder 18 is reduced in diameter to form a small diameter portion 20 as shown in FIG.
It is said that

As shown in FIG. 4, a main body rubber 14 is stretched between the inner cylinder 12 and the intermediate cylinder 18 as an elastic body. This main body rubber 14 is vulcanized and bonded to the outer peripheral surface of the inner cylinder 12 and the inner peripheral surface of the intermediate cylinder 18.

As shown in FIGS. 1 and 2, the main body rubber 14 has a notch 1 cut out toward the inner cylinder 12.
4A is formed. This notch 14A forms a main liquid chamber 28 with a top plate 22A of the partition plate 22 disposed corresponding to the notch 20A formed in the small diameter portion 20 of the intermediate cylinder 18. This main liquid chamber 28 is filled with a liquid 26 such as ethylene glycol.

As shown in FIG. 4, an orifice member 34 made of a rubber material is vulcanized and bonded to a portion of the small diameter portion 20 of the intermediate cylinder 18 excluding the notch portion 20A. This orifice member 34 is formed in a substantially arc shape, and its outer peripheral surface has the same outer diameter as the large diameter portions 18A and 18B of the intermediate cylinder 18.

As shown in FIGS. 2 to 4, a substantially C-shaped groove 36 is formed in the circumferential direction of the intermediate cylinder 18 on the side of the orifice member 34 toward the large diameter portion 18A. As shown in FIGS. 3 and 4, an opening 36A is formed at one longitudinal end of the groove 36 and communicates with the main liquid chamber 28. Also,
As shown in FIG. 1, the other end of the groove 36 is inserted into an opening 22B formed in the partition plate 22, and an opening 36B is formed at the other end.

As shown in FIG. 4, a generally arc-shaped groove 38 with a wide groove width is formed on the side of the intermediate cylinder 18 of the orifice member 34 in the direction of the large diameter portion 18B. This groove 38 is the groove 36
and the longitudinal directions are parallel to each other. As shown in FIGS. 1 and 4, a portion of the groove 38 corresponding to the flat plate portion 20B of the small diameter portion 20 of the intermediate cylinder 18 is a flat portion 38A, and a portion of the groove 38 corresponding to the circular arc portion 20C of the small diameter portion 20 is a circular arc portion. It is said to be 38B. A rising surface 38C is formed at the end of the flat portion 38A opposite to the circular arc portion 38B. An opening 38D is formed at one longitudinal end of the groove 38, and the groove 38 communicates with the main liquid chamber 28. As shown in FIG. 2, the cross-sectional area of the groove 38 is set to be considerably larger than the cross-sectional area of the groove 36.

As shown in FIG. 1, a thin film of rubber 40 as an elastic body is vulcanized and bonded to the inner peripheral surface of the outer cylinder 16. Therefore, when the intermediate cylinder 18 is inserted into the outer cylinder 16, the large diameter portions 18A and 18B of the intermediate cylinder 18 and the orifice member 34
The outer circumferential surface of is brought into pressure contact with the thin film rubber 40. As a result, the groove 36 serves as a shake orifice 30 as a first restriction passage, and the groove 38 serves as an idle orifice 32 as a second restriction passage having a larger diameter than the shake orifice 30.

A portion of the thin rubber film 40 corresponding to the partition plate 22 and a portion corresponding to the plane portion 38A are not vulcanized and bonded to the outer cylinder 16, but are attached to the diaphragms 42 and 4, respectively.
It is said to be 4. The diaphragm 42 and the partition plate 22 form a first sub-liquid chamber 46 as a small liquid chamber. This first sub-liquid chamber 46 is also filled with a liquid 26 such as ethylene glycol, similar to the main liquid chamber 28. The first sub-liquid chamber 46 corresponds to the opening 36B of the groove 36,
The groove 36 communicates with a first sub-liquid chamber 46 .

An air chamber 43 is formed by the diaphragm 42 and the outer cylinder 16, and by allowing the diaphragm 42 to move, the first sub-liquid chamber 46 can be expanded and contracted. A circular hole 47 is coaxially formed in the outer cylinder 16 and the bracket 17 corresponding to the air chamber 43 so as to communicate with the outside air.

As shown in FIG. 1, a second sub-liquid chamber 48 is formed inside the idle orifice 32 by the flat portion 38A of the groove 38 of the orifice member 34, the raised surface 38C, and the diaphragm 44. This second sub-liquid chamber 48
Similarly to the main liquid chamber 28, the main liquid chamber 28 is also filled with a liquid 26 such as ethylene glycol.

Outer cylinder 16 corresponding to the diaphragm 44
Coaxial circular holes 50 and 51 are formed in the bracket 17. One axial end portion 52A of the pipe 52 is inserted into these circular holes 50 and 51.

As shown in FIG. 1, the other end 52B of the pipe 52 communicates with an intake manifold 70 of an engine 76. Further, an enlarged diameter part 54 is formed in the middle part of the pipe 52, and the inner diameter of the pipe 52 is set to be large.
This prevents air attenuation from occurring.

The intake manifold 70 communicates with the cylinder 72 via an intake valve 74. Therefore, when the piston 78 serving as a negative pressure means moves away from the intake valve 74 (downward in FIG. 1), the intake valve 74 is opened and the inside of the intake manifold 70 becomes negative pressure. As a result, the insides of the pipe 52 and the air chamber 43 become negative pressure.

A solenoid valve 56 as negative pressure means is installed between the enlarged diameter portion 54 of the pipe 52 and the intake manifold 70. This solenoid valve 56 is connected to and controlled by control means 60. The solenoid valve 56 has a built-in solenoid coil 56A.
Inside, a movable iron core 56B is connected to an electromagnetic coil 56 by an exciting current.
It is designed to be attracted to and separated from A. As a result,
The valve body 56C connected to the movable core 56B exits from the pipe 52 when the movable core 56B is attracted by the electromagnetic coil 56A, and advances into the pipe 52 when the movable core 56B is separated from the electromagnetic coil 56A. It has become.

Therefore, unless the valve body 56C of the electromagnetic valve 56 shuts off the pipe 52, the pressure in the pipe 52 and the air chamber 43 becomes negative. When the valve body 56C advances into the pipe 52 and shuts off the pipe 52, it prevents the pipe 52 and the air chamber 43 from becoming negative pressure.

The control means 60 is driven by the vehicle power source, receives detection signals from at least a vehicle speed sensor 62 and an engine rotation sensor 64, and is capable of detecting vehicle speed and engine rotation speed. Accordingly, the control means 60 determines whether the vehicle is idling or shaking.

Next, the operation of the embodiment will be explained. When a vehicle equipped with the vibration isolator 10 according to the present invention as an engine mount runs at a speed of 70 to 80 km/h, shake vibration (1
5 HZ) may occur. The control means 60 is a vehicle speed sensor 6
2. The engine rotation speed sensor 64 determines whether shake vibration is occurring. When the control means 60 determines that shake vibration is occurring, the control means 60 energizes the solenoid valve 56 . Therefore, the movable iron core 56B is connected to the electromagnetic coil 56B.
The pipe 52 is not shut off by the valve body 56C. As a result, the piston 78 of the engine 76 moves away from the intake valve 74 in the air chamber 43, thereby creating a negative pressure state. Therefore, the diaphragm 44 comes into close contact with the inner circumferential surface of the outer cylinder 16, as shown by the imaginary line in FIG. As a result, the expandable and contractible second sub-liquid chamber 48 is not formed in the idle orifice 32, and the liquid 26 no longer flows in the idle orifice 32.

Therefore, the liquid 26 is transferred to the shake orifice 3.
The main liquid chamber 28 and the first sub-liquid chamber 46 are exchanged by passing only through the main liquid chamber 28 and the first sub-liquid chamber 46. Furthermore, since the cross-sectional area of the shake orifice 30 through which the liquid 26 passes is small, the shake vibration is absorbed by the resistance and liquid column resonance when the liquid 26 passes through the shake orifice 30.

[0044] In addition, when the engine is idling or the vehicle speed is 5 km/h or less, idle vibration (20
~40Hz) occurs. The control means 60 uses a vehicle speed sensor 62 and an engine rotation speed sensor 64 to determine whether or not idle vibration is occurring. When the control means 60 determines that idle vibration is occurring, the control means 60 does not energize the electromagnetic valve 56, so the movable iron core 56B is not attracted by the electromagnetic coil 56B. Therefore, the pipe 52 is connected to the valve body 56C.
The interior of the air chamber 43 is blocked by the engine 76.
The downward movement of the piston 78 in FIG. 1 does not create a negative pressure state.

As a result, the diaphragm 44 approaches the flat portion 38A of the groove 38 (as shown by the solid line in FIG. 1), and a second sub-liquid chamber 48 that can be expanded and contracted is formed within the idle orifice 32. Therefore, even if the shake orifice 30 becomes clogged due to idle vibration and the liquid 26 no longer passes through the shake orifice 30, the liquid 26 will pass through the idle orifice 32 with a large flow path area and enter the main liquid chamber 28. and the second sub-liquid chamber 48. Therefore, idle vibration can be reliably absorbed by the liquid column resonance of the liquid 26.

[Second Embodiment] Vibration isolating device 10 according to the present invention
A second embodiment of the present invention will be described with reference to FIGS. 5 to 7.

The same components as those in the first embodiment are given the same reference numerals, and the explanation thereof will be omitted.

As shown in FIG. 5, this vibration isolator 10 includes a mounting frame 112 for mounting on a vehicle body (not shown).
is provided, and the annular portion 1 of this mounting frame 112
An outer cylinder 116 is inserted into 14. A thin rubber layer 118 is vulcanized and bonded to the inside of this outer cylinder 116. This thin rubber layer 118 has a diaphragm 120 whose upper part is separated from the inner peripheral surface of the outer cylinder 116, and a diaphragm 121 whose lower part is separated from the inner peripheral surface of the outer cylinder 116.
It is said that As shown in FIG. 6, the diaphragm 121
is formed to have a substantially spherical convex shape toward the inside of the outer cylinder 116, and an air chamber 136 is formed between the inner periphery of the outer cylinder 116 and the diaphragm 121.

[0049] Inside this outer cylinder 116, there is an intermediate block 1.
22 and intermediate block 124 are inserted. The intermediate block 122 has flange portions 122A formed at both ends in the axial direction, and the outer circumferential surface of the intermediate block 122 is in close contact with the thin rubber layer 118.
An intermediate block 124 is fitted between the flange portions 122A. As shown in FIG.
has a substantially semicircular block shape when viewed from the axial direction of the outer cylinder 116, and its outer peripheral surface is in close contact with the thin rubber layer 118.

Furthermore, a notch 122B is formed in the center of the intermediate block 122 facing the intermediate block 124.
An inner cylinder 126 passes through it. This inner cylinder 126 is the outer cylinder 11
6, and a main body rubber 128 as an elastic body is stretched between the intermediate block 122 and the intermediate block 122. This allows the inner cylinder 126 to move relative to the outer cylinder 116.

A part of the outer peripheral surface of the main body rubber 128 is in close contact with the top surface 124A of the intermediate block 124, and a notch 128A forming a main liquid chamber 130 between it and the intermediate block 124 is formed in a part of the intermediate part. is formed. Further, between the flange portions 122A of the intermediate block 122, the inner peripheral surface is formed by the intermediate block 122, and the outer peripheral surface is formed by the thin rubber layer 118.
A first sub-liquid chamber 132 is defined by the diaphragm 120. Note that an air chamber 131 is formed between the diaphragm 120 and the outer cylinder 116, and is communicated with the outside as necessary.

As shown in FIGS. 6 and 7, a passage 164 is formed around the outer periphery of the intermediate block 124. As shown in FIGS. One end of this passage 164 is connected to the first sub-liquid chamber 132, and the other end is connected to the main liquid chamber 130 via an opening 164A.
Shake orifice 162 surrounded by outer cylinder 116
It consists of

[0053] A notch 12 is provided at the bottom of the intermediate block 124.
4A is formed, and this notch 124A is surrounded by the thin rubber layer 118 and the diaphragm 121, and a second cutout 124A is formed.
A sub-liquid chamber 133 is configured. Also, the intermediate block 12
4 includes an idler having a rectangular longitudinal section, one end of which is connected to the second sub-liquid chamber 133, and the other end of which is connected to the main liquid chamber 130 through an opening 160A formed in the inner circumference of the intermediate block 124. An orifice 160 is formed.

Note that these main liquid chamber 130, first sub-liquid chamber 132, second sub-liquid chamber 133, and idle orifice 160
The shake orifice 162 is filled with a liquid 138 such as ethylene glycol.

Thin rubber layer 1 corresponding to the air chamber 131
18, one end portion 52A of the pipe 52 is inserted through the outer cylinder 116 and the annular portion 114. Note that the pipe 52 is connected to an intake manifold 70 (not shown) of an engine 76 (not shown) as in the first embodiment.

Next, the operation of this embodiment will be explained. When the vibration is shake vibration (less than 15 Hz), the control means 60 energizes the solenoid valve 56 as in the first embodiment. As a result, the inside of the air chamber 136 is brought into a negative pressure state, and the diaphragm 121 comes into close contact with the inner circumferential surface of the outer cylinder 116 as shown by the imaginary line in FIG. As a result, the second sub-liquid chamber 133 cannot expand or contract, and the flow of the liquid 128 within the idle orifice 160 is eliminated. Therefore, the liquid 128 passes only through the shake orifice 162 to the main liquid chamber 130 and the first sub-liquid chamber 13.
2, the liquid 128 flows through the shake orifice 16.
The shake vibration is absorbed by the resistance and liquid column resonance when passing through the liquid column.

Further, when the vibration is idle vibration, the control means 60 does not energize the solenoid valve 56 and does not bring the inside of the air chamber 136 into a negative pressure state. As a result, the diaphragm 121 swells toward the second sub-liquid chamber 133 and enters a free state (as shown by the solid line in FIG. 6), so that the second sub-liquid chamber 133 can expand and contract. Therefore, the liquid 128 passes through the idle orifice 160 and moves back and forth between the main liquid chamber 130 and the second sub-liquid chamber 133, and the liquid column resonates within the idle orifice 160, thereby absorbing idle vibration.

[Third Embodiment] Vibration isolating device 10 according to the present invention
A third embodiment will be described with reference to FIGS. 8 and 9.

Note that the same components as those in the first embodiment are given the same reference numerals, and the explanation thereof will be omitted.

As shown in FIG. 8, the bottom plate 212 of the vibration isolator 10 has a mounting bolt 214 protruding from the lower center thereof, and is fixed to the body of an automobile (not shown), as an example.

The periphery of the bottom plate 212 is a cylindrical standing wall portion 212A bent at right angles, and a flange portion 212B bent at right angles is continuously formed at the upper end of this standing wall portion 212A.

The lower end of the outer cylinder 216, which is fixed to the bottom plate 212, is fixed to the flange portion 212B by caulking. A peripheral edge of a diaphragm 218 is held between the flange portion 212B and the lower end of the outer cylinder 216. An air chamber 220 is formed between the diaphragm 218 and the bottom plate 212, and is communicated with the outside as necessary.

The upper end of the outer cylinder 216 is an expanded part 216B whose inner diameter is gradually enlarged, and the outer periphery of the main body rubber 222 is vulcanized and bonded. The outer circumferential portion 224A of the support base 224 is vulcanized and bonded to the inner circumferential portion of the main body rubber 222. Further, a portion of the main body rubber 222 extends to the cylindrical portion 216C and a portion of the lower end of the outer tube 216 and is vulcanized and bonded. The support base 224 is a mounting part for an engine (not shown), and a mounting bolt 226 for fixing the engine is protruded from the support base 224.

Here, the inner peripheral part of the outer cylinder 216, the vibration absorbing main body 22
2 and the diaphragm 218.
8 is formed. This liquid chamber 228 is filled with a liquid 229 such as ethylene glycol.

An orifice member 230 is disposed within the liquid chamber 228 to divide the liquid chamber 228 into a main liquid chamber 232 and a first sub-liquid chamber 23.
It is divided into 4 parts. The orifice member 230 is made of synthetic resin or the like and has a substantially hat-shaped cross section.

As shown in FIGS. 8 and 9, a narrow groove 244 having a rectangular cross section is formed along the circumferential direction on the outer periphery of the orifice member 230. Outer cylinder 216 of this narrow groove 244
The side is closed by an extension of the main body rubber 222 to form a shake orifice 252. This shake orifice 252 has a rectangular opening 24 at one end in the longitudinal direction.
4A, and the other end communicates with the first sub-liquid chamber 234 via an opening 244B.

In addition, a rectangular hole 242 is formed in the orifice member 230 from the outer periphery to the opposite outer periphery, and the tip of this rectangular hole 242 communicates with the main liquid chamber 232 through an opening 242A. It constitutes an orifice 246.

A boss 260 is fixed to the outer periphery of the cylindrical portion 216C of the outer cylinder 216 corresponding to the rectangular hole 242. This boss 260 has a recess 262 formed on the side opposite to the cylindrical portion 216C, and this recess 262 is closed by a pressing plate 264. An annular recess 266 is formed at the opening of the recess 262 .
A peripheral portion of a diaphragm 268 is held between the holding plate 264 and the holding plate 264 . In a free state, this diaphragm 268 projects in a substantially hemispherical shape toward the cylindrical portion 216C, and a second sub-liquid chamber 270 is formed between the diaphragm 268 and the recessed portion 262. This second sub-liquid chamber 270
and the rectangular hole 242, the main body rubber 222 and the outer cylinder 2
16 and the boss 260 through a through hole 272 that communicates with the rectangular hole 242 .

An air chamber 274 is formed between the diaphragm 268 and the holding plate 264, and this air chamber 274 is connected to the engine 76 (not shown) through a pipe 52 connected to the holding plate 264. ) is connected to an intake manifold 70 (not shown).

Next, the operation of the third embodiment will be explained. In the vibration isolator 10 of this embodiment, a bottom plate 12 is fixed to a vehicle body (not shown) via mounting bolts 14, and an engine is mounted on a support base 24.
It is mounted on top and fixed with mounting bolts 26.

When the vibration is shake vibration (less than 15Hz), the control means 60 controls the solenoid valve 56 as in the first embodiment.
energize. As a result, the inside of the air chamber 274 is brought into a negative pressure state, and the diaphragm 268 comes into close contact with the inner wall surface of the pressing plate 264 as shown by the imaginary line in FIG. As a result,
The second sub-liquid chamber 270 cannot expand or contract, and the flow of the liquid 229 within the idle orifice 246 is eliminated. Therefore, the liquid 229 passes between the main liquid chamber 232 and the first sub-liquid chamber 234 only through the shake orifice 252, and the liquid 229
The shake vibration is absorbed by the resistance and liquid column resonance when the liquid passes through the shake orifice 252.

Further, when the vibration is idle vibration, the control means 60 does not energize the solenoid valve 56 and does not bring the inside of the air chamber 274 into a negative pressure state. As a result, the diaphragm 268 swells toward the second sub-liquid chamber 270 and enters a free state (solid line state in FIG. 8), allowing the second sub-liquid chamber 270 to expand and contract. Therefore, the liquid 229 passes through the idle orifice 246 and moves back and forth between the main liquid chamber 232 and the second sub-liquid chamber 270, and the liquid 229 resonates in the liquid column within the idle orifice 242, thereby absorbing idle vibration.

In this embodiment, since the second auxiliary liquid chamber 270 and the air chamber 274 are provided outside the outer cylinder 216, there is no possibility that the structure inside the outer cylinder 216 will become complicated.

[Fourth embodiment] Vibration isolating device 10 according to the present invention
A fourth embodiment will be described with reference to FIGS. 10 and 11.

The fourth embodiment is a modification of the third embodiment, and the same components as those in the third embodiment are denoted by the same reference numerals, and the explanation thereof will be omitted.

As shown in FIG. 10, in the vibration isolator 10 of the fourth embodiment, a cylindrical block-shaped outer cylinder 316 is bolted to the flange part 212B of the bottom plate 212, and the flange part 212B and the outer cylinder 316 are connected by bolts. The orifice member 230 and the peripheral edge of the diaphragm 218 are sandwiched between the lower end and the lower end.

The upper end of the inner circumferential surface of the outer cylinder 316 is an enlarged part 316B whose inner diameter is gradually enlarged, and the main body rubber 2
The outer periphery of 22 is vulcanized and bonded. In addition, the main body rubber 22
2 extends to a part of the lower end of the inner circumference of the outer cylinder 316 and is vulcanized and bonded.

The orifice member 2 is provided on the outer periphery of the outer cylinder 316.
A recess 362 is formed at a position corresponding to the rectangular hole 242 of No. 30, and this recess 362 is closed by a block 364. A through hole 372 is formed at the bottom of the recess 362, and this through hole 372 communicates with the rectangular hole 242 via a hole 222A passing through the main body rubber 222.

An annular recess 366 is formed on the outer periphery of the bottom of the recess 362, and the peripheral edge of the diaphragm 368 is held between the annular recess 266 and the block 364. In a free state, the diaphragm 368 projects into the through hole 372 in a substantially hemispherical shape, and the through hole 372 is closed by the diaphragm 368 to form a second sub-liquid chamber 370 . Further, the surface of the block 364 facing the diaphragm 368 is connected to the diaphragm 36
The diaphragm 368 has a substantially symmetrical shape with respect to the peripheral edge of the diaphragm 368 as a plane of symmetry, that is, a substantially hemispherical concave shape.

An air chamber 374 is provided between the diaphragm 368 and the block 364, and this air chamber 374 is connected to the engine 76 (not shown) via the pipe 52 connected to the block 364. It communicates with an intake manifold 70 (not shown).

In the vibration isolator 10 of the fourth embodiment, the air chamber 3
When the inside of 74 is in a negative pressure state, the diaphragm 26
8 is inverted at the periphery of the diaphragm 368, so that no wrinkles occur locally, and it can reliably come into close contact with the inner wall surface of the block 264 as shown by the imaginary line in FIG.

In this embodiment, the air chamber 374 is connected to the outer cylinder 316.
The number of parts can be reduced compared to a configuration in which an air chamber is provided outside the outer cylinder 316.

[Fifth embodiment] Vibration isolating device 10 according to the present invention
A fifth embodiment of the present invention will be described with reference to FIGS. 12 and 13.

The fifth embodiment is a modification of the fourth embodiment, and the same components as the fourth embodiment are denoted by the same reference numerals, and the explanation thereof will be omitted.

As shown in FIG. 13, in the vibration isolator 10 of the fifth embodiment, the orifice member 430 is composed of an upper orifice member 430A and a lower orifice member 430B. A diaphragm 468 is sandwiched between them.

As shown in FIG. 12, the upper orifice member 430A has a substantially hemispherical recess 476 formed on the diaphragm 468 side.
An air chamber 474 is provided between the air chamber 76 and the air chamber 76 . This air chamber 4
74 is communicated with an intake manifold 70 (not shown) of an engine 76 (not shown) via a passage 480 of the upper orifice member 430A, a through pipe 482, a connecting fitting 484, and a pipe 52, as in the first embodiment.

[0087] In addition, the lower orifice member 430B includes:
A recess 478 having an arcuate cross section is formed on the surface of the diaphragm 468, and a second sub-liquid chamber 470 is defined between the diaphragm 468 and the recess 478.

As shown in FIGS. 13 and 12, a thin groove 451 having a rectangular cross section is formed on the lower outer periphery of the orifice member 430.
is formed along the circumferential direction. The outer cylinder 316 side of this narrow groove 451 is closed by an extension of the main body rubber 222 to form a shake orifice 452. One longitudinal end of the shake orifice 452 communicates with the main liquid chamber 232 through a rectangular opening 452A, and the other end communicates with the first sub-liquid chamber 434 through an opening 452B.

Furthermore, a wide groove 445 having a rectangular cross section is formed along the circumferential direction on the upper outer periphery of the orifice member 430. The wide groove 445 on the outer cylinder 316 side is closed by the extension of the main body rubber 222 to form an idle orifice 446. This idol orifice 4
46 has one longitudinal end communicated with the main liquid chamber 232 via a rectangular opening 446A, and the other end communicated with the second sub-liquid chamber 470 via a passage 446B.

In the vibration isolating device 10 of this embodiment, when the vibration is shake vibration (less than 15 Hz), the control means 60 energizes the solenoid valve 56 to close the air chamber 474 as in the fourth embodiment. With negative pressure inside, diaphragm 4
68 is brought into close contact with the recess 476 as shown by the imaginary line in FIG. 12, so that the second sub-liquid chamber 470 cannot be expanded or contracted, thereby preventing the flow of the liquid 229 within the idle orifice 446.

[0091] Also, the idle orifice 4 of this embodiment
Since 46 is provided on the outer periphery of the orifice member 430, it is the idle orifice 24 of the vibration isolator 10 of the fourth embodiment.
Compared to No. 6, the dimensions in the liquid movement direction are longer and the passage resistance is greater, so the idle vibration damping ability is higher.

In the embodiment, the piston 78 of the engine 76 is used as the negative pressure means, but a separate device for sucking the air in the air chamber 43 may be provided separately.

[0093] In addition, although the bush type and composite type vibration isolators are shown in the embodiments, the present invention is not limited thereto, and vibration isolators other than the bush type and composite type may be used. .

Further, in the embodiment, a vibration isolator is shown as an engine mount, but the present invention is not limited to this, and it goes without saying that it may be applied to a cab mount, a body mount, etc.

Furthermore, depending on the required conditions, the first sub-liquid chamber 46 and shake orifice 30 of the embodiment may be eliminated, and the desired vibration damping characteristics may be achieved using only the main liquid chamber 28, second sub-liquid chamber 48, and idle orifice 32. It is also possible to obtain

[0096]

As explained above, the present invention has the excellent effect of effectively attenuating and absorbing vibrations over a wide range of frequencies, although it is a single vibration isolating device.

[Brief explanation of the drawing]

FIG. 1 shows a first embodiment of the present invention, and is a partial sectional view of a vibration isolator and an engine.

FIG. 2 shows a first embodiment of the present invention, and shows II-II in FIG.
FIG.

FIG. 3 shows the first embodiment of the present invention, and FIG. 4II of the intermediate cylinder.
It is a view taken along the I line.

FIG. 4 shows a first embodiment of the present invention and is a partially exploded perspective view of a vibration isolator.

FIG. 5 is an exploded perspective view of a vibration isolator, showing a second embodiment of the present invention.

FIG. 6 shows a second embodiment of the present invention and is a sectional view of a vibration isolator.

FIG. 7 shows a second embodiment of the present invention, and FIG. 6VI of the intermediate cylinder.
I is a view taken along the line.

FIG. 8 shows a third embodiment of the present invention and is a sectional view of a vibration isolator.

FIG. 9 shows a third embodiment of the present invention, and shows IX-IX in FIG.
FIG.

FIG. 10 shows a fourth embodiment of the present invention and is a sectional view of a vibration isolator.

FIG. 11 shows a fourth embodiment of the present invention, and shows the XI-
It is a sectional view taken along the line XI.

FIG. 12 shows a fifth embodiment of the present invention and is a sectional view of a vibration isolator.

FIG. 13 is a partially cross-sectional perspective view of an orifice member showing a fifth embodiment of the present invention.

[Explanation of symbols]

10 Vibration isolator 12 Inner cylinder 14 Main body rubber (elastic body) 16 Outer cylinder 26 Liquid 28 Main liquid chamber 30 Shake orifice (first restriction passage) 3
2 Idle orifice (second restriction passage) 40
Thin film rubber (thin elastic body) 42 Air chamber 44 Diaphragm 46 First sub-liquid chamber 48 Second sub-liquid chamber 56 Solenoid valve (negative pressure means) 78 Piston (negative pressure means) 116 Outer cylinder 118 Thin rubber layer (thin elastic body) ) 121 Diaphragm 126 Inner cylinder 128 Main body rubber (elastic body) 130 Main liquid chamber 132 First sub-liquid chamber 133 Second sub-liquid chamber 136 Air chamber 160 Idle orifice (second restriction passage) 16
2 Shake orifice (first restriction passage) 212
Bottom plate (first member) 222 Main body rubber (elastic body) 230 Orifice member (partition member) 224 Support stand (second member) 232 Main liquid chamber 234 First sub-liquid chamber 246 Idle orifice (second restriction passage) 25
2 Shake orifice (first restriction passage) 268
Diaphragm 270 Second sub-liquid chamber 274 Air chamber 368 Diaphragm 370 Second sub-liquid chamber 374 Air chamber 446 Idle orifice (second restriction passage) 45
2 Shake orifice (first restriction passage) 468
Diaphragm 470 Second sub-liquid chamber 474 Air chamber

Claims (7)

[Claims] 1. An outer cylinder connected to one of the vibration generating part and the vibration receiving part, an inner cylinder connected to the other of the vibration generating part and the vibration receiving part, and between the outer cylinder and the inner cylinder. an elastic body that is provided and deforms when vibration occurs; a main liquid chamber that can be expanded and contracted using the elastic body as part of a partition; a first sub-liquid chamber that is disposed inside the outer cylinder; a first restriction passage arranged inwardly and connecting the main liquid chamber and the first sub-liquid chamber; a second restriction passage arranged inwardly of the outer cylinder and communicating with the main liquid chamber; a second sub-liquid chamber arranged inside the outer cylinder and provided in a part of the second restriction passage; a diaphragm arranged inside the outer cylinder and forming a partition wall of the second sub-liquid chamber; , disposed inside the outer cylinder and on the opposite side of the diaphragm to the second sub-liquid chamber side, and brings the diaphragm into close contact with the inner wall surface to prevent movement of the diaphragm when the inside becomes negative pressure. 1. A vibration isolator comprising: an air chamber that substantially disappears when the vibration is applied; and negative pressure means that makes the inside of the air chamber a negative pressure. 2. The vibration isolator according to claim 1, wherein the diaphragm is formed of a part of an elastic body provided on the inner circumferential surface of the outer cylinder and connecting the outer cylinder and the inner cylinder. Device. 3. The vibration isolating device according to claim 1, wherein the diaphragm is comprised only of an elastic body. 4. In a free state, the diaphragm has a convex R-shaped cross section toward the second sub-liquid chamber, and the inner wall surface of the air chamber facing the diaphragm is located between the second sub-liquid chamber and the air chamber. Claim 1 characterized in that the shape is substantially symmetrical to the shape of the diaphragm, with a plane of symmetry between the diaphragms and the diaphragm.
, the vibration isolator according to any one of claims 2 and 3. 5. 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 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 can be expanded and contracted using the elastic body as part of a partition; a first sub-liquid chamber that is isolated from the main liquid chamber; and a partition member that isolates the main liquid chamber and the first sub-liquid chamber. , a first restriction passage formed in the partition member and communicating with the main liquid chamber and the first sub-liquid chamber; a second restriction passage formed in the partition member and communicating with the main liquid chamber; a second sub-liquid chamber provided in a part of the second restriction passage; a diaphragm forming a partition wall of the second sub-liquid chamber; and an inner side of the outer cylinder and a side of the second sub-liquid chamber of the diaphragm. an air chamber which is disposed on the opposite side of the air chamber and which causes the diaphragm to come into close contact with the inner wall surface to prevent movement of the diaphragm and substantially disappear when the inside is brought into negative pressure; A vibration isolating device characterized in that it is provided with a negative pressure means. 6. The vibration isolator according to claim 5, wherein the air chamber is provided in either the first member or the second member. 7. The vibration isolator according to claim 5, wherein the air chamber is provided outside the first member and the second member.