JP6483444B2 - Vibration isolator - Google Patents

Description

  The present invention relates to a vibration isolator.

  Conventionally, for example, a vibration isolator described in Patent Document 1 below is known. The vibration isolator includes a cylindrical first mounting member connected to one of the vibration generating unit and the vibration receiving unit, a second mounting member connected to the other, and an elastic connecting the both mounting members. The body and the liquid chamber in the first mounting member enclosing the liquid are partitioned, the first liquid chamber having the elastic body as a part of the wall surface, and the second liquid communicating with the first liquid chamber through the restriction passage And a room.

JP 2009-275748 A

  However, the conventional vibration isolator has a problem that when a high-frequency vibration having a frequency higher than the resonance frequency of the restriction passage is input, a resonance phenomenon called surging occurs and the dynamic spring constant increases.

  The present invention has been made in view of the above-described circumstances, and an object thereof is to suppress the occurrence of surging.

In order to solve the above problems, the present invention proposes the following means.
The vibration isolator according to the present invention includes a cylindrical first attachment member connected to one of the vibration generating portion and the vibration receiving portion, a second attachment member connected to the other, and both of these attachment members. The elastic body to be connected and the liquid chamber in the first mounting member in which the liquid is sealed are partitioned, and the first liquid chamber having the elastic body as a part of the wall surface, and the restriction passage to the first liquid chamber And a second liquid chamber communicating with the first liquid chamber, wherein the liquid chamber is partitioned in the axial direction of the first mounting member, and the first liquid chamber is formed on one side in the axial direction. And a partition member that forms the second liquid chamber on the other side in the axial direction, and a part of the wall surface of the second liquid chamber is formed by a rigid lid that closes the first mounting member from the other side. is, the first liquid chamber and the second liquid chamber is lower vacuum than the liquid pressure is atmospheric pressure Characterized in that it is a state.

In this type of vibration isolator, the spring constant of the entire vibration isolator varies depending on the spring constant of the elastic body and the spring constant based on the hydraulic pressure of the first and second liquid chambers. Here, in this vibration isolator, since the first liquid chamber and the second liquid chamber are in a reduced pressure state, the spring constant based on the liquid pressure in the first and second liquid chambers described above is kept low, The spring constant can be lowered. As a result, it is possible to suppress the occurrence of surging when inputting high-frequency vibrations, and to suppress an increase in the dynamic spring constant. As a result, for example, when this vibration isolator is applied to an automobile, it is possible to reduce the booming noise and to ensure the ride comfort.
Moreover, in order to reduce the spring constant of the entire vibration isolator, the spring constant based on the fluid pressures of the first and second fluid chambers is lowered, so that the elastic body characteristics are maintained by maintaining the spring constant of the elastic body. Can be secured. Thereby, for example, the initial load applied to the vibration isolator when the vibration isolator is interposed between the vibration generator and the vibration receiver can be reliably received by the elastic body.

  In this case, since a part of the wall surface of the second liquid chamber is formed by the rigid lid, the second liquid chamber is defined by the first mounting member, the partition member, and the rigid lid, and the second liquid chamber is surely formed. It can be kept under reduced pressure.

  According to the present invention, occurrence of surging can be suppressed.

It is a longitudinal cross-sectional view which shows the vibration isolator which concerns on one Embodiment of this invention. It is a longitudinal cross-sectional view of the vibration isolator shown in FIG. 1, Comprising: It is a figure explaining the manufacturing method of a vibration isolator.

Hereinafter, with reference to FIG. 1 and FIG. 2, the vibration isolator which concerns on one Embodiment of this invention is demonstrated.
As shown in FIG. 1, the vibration isolator 10 includes a cylindrical first mounting member 11 connected to one of a vibration generating unit and a vibration receiving unit, and a second mounting member 12 connected to the other. An elastic body 13 that elastically connects the first mounting member 11 and the second mounting member 12, and a liquid chamber 16 that is disposed inside the first mounting member 11 and formed inside the first mounting member 11. The partition member 15 is provided to partition the main liquid chamber (first liquid chamber) 16a and the sub liquid chamber (second liquid chamber) 16b.

  Each of these members is provided coaxially with the central axis O. Hereinafter, the direction along the central axis O is referred to as the axial direction (the axial direction of the first mounting member), and the direction orthogonal to the central axis O is referred to as the radial direction (the radial direction of the first mounting member). The direction to go around is called the circumferential direction (the circumferential direction of the first mounting member). Here, the liquid chamber 16 is divided into a main liquid chamber 16a on one side in the axial direction (lower side in FIG. 1) and the other side in the axial direction (see FIG. 1). 1) and a secondary liquid chamber 16b. In these main liquid chamber 16a and sub liquid chamber 16b, for example, a liquid such as ethylene glycol, water, or silicone oil is sealed.

  The first mounting member 11 includes a plurality of sliding cylinders 21 that are slidably fitted to each other in the axial direction. In this embodiment, the first mounting member 11 includes a pair of sliding cylinders 21, and a small diameter sliding small cylinder 22 is fitted in a large diameter sliding large cylinder 23. The sliding small cylinder 22 is positioned on one side in the axial direction with respect to the sliding large cylinder 23, and the other end in the axial direction of the sliding small cylinder 22 is on the one side in the axial direction of the sliding large cylinder 23. It is fitted in the end.

  Between the sliding cylinders 21 that are fitted to each other, a restriction portion 25 that restricts the sliding cylinders 21 from sliding in the axial direction is provided. The restricting portion 25 includes a pin member 26 that is integrally inserted in the radial direction with the sliding cylinder 21 that is fitted to each other. A plurality of pin members 26 are arranged at intervals in the circumferential direction, and are inserted through insertion holes 27 formed in the sliding cylinder 21.

The first mounting member 11 is closed from the other side in the axial direction by a rigid lid 28. The rigid lid 28 is connected to the other end portion of the first mounting member 11 in the axial direction, and is integrally formed with the sliding large cylinder 23 in the illustrated example. The rigid lid 28 is formed with a liquid injection hole (not shown). The injection hole is sealed with a plug (not shown).
The second mounting member 12 is disposed in one end of the first mounting member 11 in the axial direction, and protrudes from the sliding small tube 22 to one side in the axial direction in the illustrated example.

  The elastic body 13 is a member made of a resin material such as rubber. The elastic body 13 is vulcanized and bonded separately to the inner peripheral surface of one end of the first mounting member 11 in the axial direction and the outer peripheral surface of the second mounting member 12. The elastic body 13 is formed in a cylindrical shape that protrudes from one end in the axial direction of the first mounting member 11 toward one side in the axial direction and is gradually reduced in diameter toward the one side in the axial direction. Yes.

  The elastic body 13 closes one end in the axial direction together with the second mounting member 12, and defines the liquid chamber 16 between the first mounting member 11 and the rigid lid 28. The partition member 15 is disposed in the liquid chamber 16 while being filled with the liquid. The partition member 15 defines a main liquid chamber 16 a with the elastic body 13, and a sub liquid chamber 16 b with the rigid lid 28.

  The partition member 15 is integrally formed of, for example, an aluminum alloy or resin. The partition member 15 is fitted in the first attachment member 11. In the illustrated example, the partition member 15 is liquid-tightly fitted in the sliding large cylinder 23 of the first mounting member 11. The partition member 15 is separated from the sliding small tube 22 on the other side in the axial direction.

  The partition member 15 is provided with a restriction passage 29 that communicates the main liquid chamber 16a and the sub liquid chamber 16b. The flow path length and flow path cross-sectional area of the restriction passage 29 are set (tuned) so that the resonance frequency of the restriction passage 29 becomes a predetermined frequency. Examples of the predetermined frequency include a frequency of idle vibration (for example, a frequency of 18 Hz to 30 Hz and an amplitude of ± 0.5 mm or less), and a shake vibration having a frequency lower than that of the idle vibration (for example, or a frequency of 14 Hz or less). , The amplitude of which is greater than ± 0.5 mm).

  In the present embodiment, the main liquid chamber 16a and the sub liquid chamber 16b are in a reduced pressure state in which the liquid pressure is lower than the atmospheric pressure. The main liquid chamber 16a and the sub liquid chamber 16b are in a depressurized state in a non-mounted state before the vibration isolator 10 is interposed between the vibration generating unit and the vibration receiving unit.

  Next, a method for manufacturing the vibration isolator will be described.

First, the first mounting member 11, the second mounting member 12, the elastic body 13, the partition member 15, and the rigid lid 28 are assembled, and a liquid chamber space serving as a liquid chamber is defined in the first mounting member 11. At this time, as shown in FIG. 2, the first mounting member 11 is contracted in the axial direction with respect to the completed state by adjusting the size in the axial direction of the fitting portions of the sliding cylinders 21 that fit together. deep. At this time, the liquid chamber space is opened to the outside through the injection hole.
Thereafter, the liquid chamber 16 is formed in the first attachment member 11 by injecting the liquid into the liquid chamber space through the injection hole, filling the liquid chamber space with the liquid, and sealing the injection hole with a stopper. .

Then, the sliding cylinders 21 of the first mounting member 11 are slid in the axial direction, and the sliding small cylinder 22 of the first mounting member 11 is slid to one side in the axial direction with respect to the sliding large cylinder 23. . As a result, the volume of the liquid chamber 16 is expanded, and the main liquid chamber 16a and the sub liquid chamber 16b are in a reduced pressure state. At this time, in the example shown in the figure, the volume of the main liquid chamber 16a is expanded, so that a fluctuation in the hydraulic pressure occurs in the main liquid chamber 16a, and this fluctuation in the hydraulic pressure is transmitted to the sub liquid chamber 16b through the restriction passage 29. The main liquid chamber 16a and the sub liquid chamber 16b are in a reduced pressure state.
Thereafter, the anti-vibration device 10 is formed by inserting the pin member 26 into the insertion hole 27 and restricting the relative movement of the sliding cylinders 21 in the axial direction by the restricting portion 25.

  Next, the operation of the vibration isolator will be described.

  The vibration isolator 10 is attached to, for example, an automobile and suppresses transmission of engine vibration to the vehicle body. In the vibration isolator 10, the second mounting member 12 is connected to an engine (not shown) as a vibration generating unit, while the first mounting member 11 is connected to a vehicle body as a vibration receiving unit via a bracket (not shown). At this time, an initial load is applied to the vibration isolator 10, and this initial load is received by the elastic body 13. In the present embodiment, the main liquid chamber 16a and the sub liquid chamber 16b are in a reduced pressure state in an initial state where an initial load is applied to the vibration isolator 10, but the main liquid chamber 16a and the sub liquid chamber 16b are in a reduced pressure state. The chamber 16a and the auxiliary liquid chamber 16b are not necessarily in a reduced pressure state.

  When vibration having a frequency equal to the frequency of the restriction passage 29 is input to the vibration isolator 10 in the initial state and the elastic body 13 is deformed and the hydraulic pressure in the main liquid chamber 16a fluctuates, the main liquid passes through the restriction passage 29. The liquid pressure is transmitted between the chamber 16a and the sub liquid chamber 16b to cause liquid column resonance, and the vibration is absorbed and attenuated. Note that the first mounting member 11 and the rigid lid 28 have such rigidity that they can hold a fixed shape even when the hydraulic pressure in the main liquid chamber 16a and the sub liquid chamber 16b is affected. ing. Here, the hydraulic pressure fluctuations in the main liquid chamber 16a and the sub liquid chamber 16b include hydraulic pressure fluctuations based on the initial load and predetermined vibrations expected to be input (for example, vibrations whose frequency is equivalent to the frequency of the restriction passage 29). ) Based on hydraulic pressure fluctuation.

According to the vibration isolator 10 according to the present embodiment as described above, the spring constant of the entire vibration isolator 10 is based on the spring constant of the elastic body 13 and the hydraulic pressures of the main liquid chamber 16a and the sub liquid chamber 16b. Varies depending on the spring constant. Here, in the vibration isolator 10, since the main liquid chamber 16a and the sub liquid chamber 16b are in a depressurized state, the spring constant based on the liquid pressure in the main liquid chamber 16a and the sub liquid chamber 16b described above is suppressed to be low. The spring constant of the entire device 10 can be lowered. As a result, it is possible to suppress the occurrence of surging when inputting high-frequency vibrations, and to suppress an increase in the dynamic spring constant. As a result, for example, when this vibration isolator 10 is applied to an automobile, it is possible to reduce the muffled noise and to ensure riding comfort.
In addition, since the spring constant based on the hydraulic pressures of the main liquid chamber 16a and the sub liquid chamber 16b is reduced in order to reduce the spring constant of the vibration isolator 10 as a whole, the spring constant of the elastic body 13 is maintained and elastic. The characteristics of the body 13 can be ensured. Thereby, for example, the initial load applied to the vibration isolator 10 when the vibration isolator 10 is interposed between the vibration generator and the vibration receiver can be reliably received by the elastic body 13.

  In addition, since a part of the wall surface of the secondary liquid chamber 16b is formed by the rigid lid 28, the secondary liquid chamber 16b is defined by the first mounting member 11, the partition member 15, and the rigid lid 28, and the secondary liquid chamber 16b. Can be reliably maintained in a reduced pressure state.

  The technical scope of the present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention.

  In the embodiment described above, the main liquid chamber 16a and the sub liquid chamber 16b are in a reduced pressure state by enlarging the volume of the liquid chamber 16, but the present invention is not limited to this. For example, the liquid chamber space may be in a vacuum state, and the main liquid chamber 16a and the sub liquid chamber 16b may be in a reduced pressure state by vacuum suction of the liquid into the liquid chamber space. It is possible to adopt a form different from the form shown in the embodiment.

  In the said embodiment, although the partition member 15 divided the liquid chamber 16 into the main liquid chamber 16a and the subliquid chamber 16b in the axial direction, this invention is not limited to this. For example, the second mounting member 12 is inserted into the first mounting member 11, and a pair of elastic bodies 13 are arranged so as to sandwich the second mounting member 12 in the radial direction. It is also possible to apply the present invention to a configuration in which the liquid chamber 16 is partitioned in the radial direction by the elastic body 13 by being separately connected to the member 12.

  In the said embodiment, the case where the 2nd attachment member 12 and an engine were connected and the 1st attachment member 11 and a vehicle body were connected was demonstrated. However, the present invention is not limited to this, and may be configured to be connected in reverse, or the vibration isolator 10 may be installed in another vibration generating unit and vibration receiving unit.

  The vibration isolator 10 according to the present invention is not limited to an engine mount of a vehicle, and can be applied to other than the engine mount. For example, the present invention can be applied to a mount of a generator mounted on a construction machine, or can be applied to a mount of a machine installed in a factory or the like.

  In addition, it is possible to appropriately replace the constituent elements in the embodiment with known constituent elements without departing from the spirit of the present invention, and the above-described modified examples may be appropriately combined.

DESCRIPTION OF SYMBOLS 10 Vibration isolator 11 1st attachment member 12 2nd attachment member 13 Elastic body 15 Partition member 16 Liquid chamber 16a Main liquid chamber (1st liquid chamber)
16b Secondary liquid chamber (second liquid chamber)
28 Rigid lid 29 Restricted passage

Claims (1)

A cylindrical first mounting member coupled to one of the vibration generating unit and the vibration receiving unit, and a second mounting member coupled to the other;
An elastic body connecting both of these mounting members;
A liquid chamber in the first mounting member in which the liquid is sealed is partitioned, and a first liquid chamber having the elastic body as a part of a wall surface and a second liquid communicating with the first liquid chamber through a restriction passage A vibration isolator comprising a chamber,
A partition that divides the liquid chamber in the axial direction of the first mounting member, forms the first liquid chamber on one side in the axial direction, and forms the second liquid chamber on the other side in the axial direction. Comprising a member,
A part of the wall surface of the second liquid chamber is formed by a rigid lid that closes the first mounting member from the other side,
The anti-vibration device according to claim 1, wherein the first liquid chamber and the second liquid chamber are in a reduced pressure state in which the liquid pressure is lower than the atmospheric pressure.

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