JP7717030B2 - Anti-vibration device - Google Patents

Description

The present invention relates to an anti-vibration device.

Conventionally, a known vibration-damping device includes an inner mounting member connected to either the vibration generating unit or the vibration receiving unit, an outer cylinder connected to the other and surrounding the inner mounting member, and an elastic body elastically connecting the inner mounting member and the outer cylinder. The elastic body includes intermediate elastic bodies arranged separately on both sides of the inner mounting member in the radial direction. A covering member is arranged between the inner mounting member and the outer cylinder, covering the spaces between adjacent intermediate elastic bodies in the circumferential direction from the outside in the radial direction and defining liquid chambers between the inner mounting member and the outer cylinder. Orifice passages are provided between the covering member and the outer cylinder, connecting the liquid chambers.

JP 2019-86102 A

However, in order to ensure the sealing of the liquid flowing through the orifice passage with this vibration isolation device, it is necessary to, for example, increase the dimensional accuracy of the covering member or vulcanize-bond a rubber film to the inner surface of the outer cylinder. This can make it difficult to ensure the sealing of the liquid flowing through the orifice passage while keeping manufacturing costs down.

The object of this invention is to provide an anti-vibration device that can ensure sealing of the liquid flowing through the orifice passage while keeping manufacturing costs down.

In order to solve the above-mentioned problems and achieve the above-mentioned objectives, the vibration-damping device of the present invention comprises an inner mounting member connected to either the vibration generating unit or the vibration receiving unit, an outer cylinder connected to the other and surrounding the inner mounting member, and an elastic body elastically connecting the inner mounting member and the outer cylinder, wherein the elastic body comprises intermediate elastic bodies disposed separately on both sides of the inner mounting member in a radial direction intersecting the central axis of the outer cylinder in a plan view seen from the axial direction along the central axis of the outer cylinder, and the inner mounting member Between the outer cylinder and the outer tube, a covering member is disposed, covering the spaces between adjacent middle elastic bodies in the circumferential direction around the central axis in the plan view from the outside in the radial direction and defining a liquid chamber between the inner mounting member and the middle elastic bodies. The elastic bodies are spaced apart in the axial direction and include a pair of end elastic bodies that are fitted into the outer cylinder and sandwich the covering member in the axial direction. An orifice passage that connects the liquid chambers is provided between the end elastic bodies and the end surface of the covering member facing in the axial direction.

According to this invention, the orifice passage that connects each liquid chamber is provided between the end elastic body of the elastic body and the end face of the covering member, so that by pressing the end elastic body against the end face of the covering member while it is fitted into the outer tube, it is possible to reliably ensure sealing of the liquid flowing through the orifice passage.
This eliminates the need to, for example, increase the dimensional accuracy of the covering member or vulcanize-bond a sealing rubber film to other members such as the outer cylinder in order to ensure the sealing of the liquid flowing through the orifice passage, thereby reducing manufacturing costs.

The covering member may comprise a first divided body and a second divided body divided in two in the axial direction, and the orifice passage may be integrally provided between the end elastic body and the end face of the first divided body, and between the respective butting faces of the first divided body and the second divided body butted against each other in the axial direction.

The covering member comprises a first segment and a second segment divided in two in the axial direction, and the orifice passage is integrally provided between the end elastic body and the end face of the first segment, and between the abutting faces of the first segment and the second segment that are abutted against each other in the axial direction. This makes it possible to easily ensure the length of the orifice passage while reliably ensuring the sealing of the liquid flowing through the orifice passage.

This invention makes it possible to keep manufacturing costs down while ensuring a tight seal against liquid flowing through the orifice passage.

1 is a cross-sectional view of an anti-vibration device shown as an embodiment of the present invention, taken at the center in the axial direction. 2 is a cross-sectional view taken along line AA of FIG. 1, shown as a first embodiment according to the present invention. FIG. FIG. 2 is a cross-sectional view taken along line AA of FIG. 1, showing a second embodiment according to the present invention.

A first embodiment of a vibration isolation device according to the present invention will be described below with reference to FIGS. 1 and 2. FIG.
The vibration-damping device 1 of this embodiment comprises an inner mounting member 11 connected to either the vibration generating part or the vibration receiving part, an outer tube 12 connected to the other and surrounding the inner mounting member 11, and elastic bodies 31, 32 that elastically connect the inner mounting member 11 and the outer tube 12.
The vibration isolation device 1 is used, for example, as a suspension bush or engine mount for an automobile, or as a mount for industrial machinery installed in a factory.
Hereinafter, the direction along the central axis O of the outer tube 12 will be referred to as the axial direction, the direction intersecting the central axis O in a plan view from the axial direction will be referred to as the radial direction, and the direction circumferentially around the central axis O will be referred to as the circumferential direction.

The inner mounting member 11 is formed in a cylindrical shape and disposed coaxially with the central axis O. In the illustrated example, the inner mounting member 11 includes a cylindrical core metal portion 21 and a resin portion 22 fixed to the outer peripheral surface of the core metal portion 21. Note that the entire inner mounting member 11 may be formed as a single unit.
The resin portion 22 includes a middle portion 26 provided in the axially middle portion of the outer peripheral surface of the core metal portion 21, and a pair of outer portions 27 each extending axially outward from the middle portion 26. The outer peripheral surface of the outer portions 27 is located radially inward of the outer peripheral surface of the middle portion 26.

The elastic bodies 31, 32 are made of rubber and are vulcanization bonded to the outer peripheral surface of the inner mounting member 11. The elastic bodies 31, 32 are arranged axially spaced apart and comprise a pair of annular end elastic bodies 31 fitted within the outer tube 12, and intermediate elastic bodies 32 arranged separately on both sides of the inner mounting member 11, sandwiching it radially between the end elastic bodies 31.

The end elastic body 31 has an end flange portion 31a that surrounds the outer portion 27 from the radial outside, and an end connecting portion 31b that connects the radial inner end of the end flange portion 31a to the outer peripheral surface of the inner mounting member 11.

The end flange portion 31a extends continuously over the entire circumferential length. The end flange portion 31a is disposed coaxially with the central axis O. An annular rigid plate 33 extending in the circumferential direction is provided on the end flange portion 31a. The rigid plate 33 is formed of a hard material such as a metal material or a synthetic resin material. The rigid plate 33 is embedded within the end flange portion 31a.
The end connecting portion 31b is formed in a cylindrical shape and extends continuously over the entire circumferential length. The end connecting portion 31b extends radially inward from the radially inner end of the end flange portion 31a toward the axially inner side. The end connecting portion 31b is connected to the axially outer end of the middle portion 26. The end connecting portion 31b is disposed coaxially with the central axis O.

The pair of middle elastic bodies 32 are formed to have the same shape and size. The middle elastic body 32 is formed entirely from a rubber material. The outer axial ends of the middle elastic bodies 32 are connected to the end elastic bodies 31.

The inner mounting member 11 has a stopper elastic portion 34 on its outer peripheral surface, protruding toward each of the liquid chambers 14a and 14b. The stopper elastic portion 34 does not necessarily have to be provided on the outer peripheral surface of the inner mounting member 11. The stopper elastic portion 34 is provided on the middle portion 26. The stopper elastic portion 34 is capable of abutting against the inner surface of the covering member 17 (described later) when the inner mounting member 11 and the outer tube 12 move toward each other. The stopper elastic portion 34 is disposed between adjacent middle elastic bodies 32 in the circumferential direction and forms part of the partition wall between the liquid chambers 14a and 14b. The stopper elastic portion 34 is circumferentially connected to the middle elastic body 32. The stopper elastic portion 34 is axially connected to the end connecting portion 31b. The stopper elastic portion 34 and the elastic bodies 31 and 32 are integrally formed from, for example, a rubber material. The entire outer peripheral surface of the inner mounting member 11 is covered with, for example, a rubber material.

A covering member 17 is disposed between the inner mounting member 11 and the outer cylinder 12. The covering member 17 covers the portion located between the pair of end elastic bodies 31 and the circumferentially adjacent middle elastic bodies 32 from the radial outside, and defines liquid chambers 14a, 14b between the inner mounting member 11 and the covering member 17. Water, ethylene glycol, or the like is sealed in the liquid chambers 14a, 14b.
The covering member 17 is made of, for example, a synthetic resin material that is harder than the material that forms the elastic bodies 31, 32. The covering member 17 is fitted between the pair of end elastic bodies 31 while being sandwiched in the axial direction.

The covering member 17 surrounds the inner mounting member 11 from the outside in the radial direction along the entire circumference. The inner surface of the covering member 17 abuts liquid-tightly against the outer surface of the middle elastic body 32, but is not in contact with the stopper elastic portion 34.

One of the axial ends of the covering member 17 and the end flange portion 31a of the end elastic body 31 are axially sandwiched and fixed by a fixing portion 23 formed on one of the axial ends of the outer tube 12. In this embodiment, a fixing flange portion 17c that protrudes radially outward and extends circumferentially is formed on the one end of the covering member 17, and the fixing flange portion 17c and the rigid plate 33 are axially sandwiched and fixed by the fixing portion 23. The fixing flange portion 17c and the radially outer end of the rigid plate 33 are layered in the axial direction with a rubber film interposed between them. Note that the fixing flange portion 17c does not necessarily have to be formed on the covering member 17.

The fixing portion 23 is recessed radially outward and has a circumferential groove that extends continuously over its entire circumferential length. The fixing flange portion 17c and the end flange portion 31a, along with the rigid plate 33, are fitted into this circumferential groove over its entire circumferential length. The fixing portion 23 is formed by bending the one end of the outer tube 12 and bulges radially outward.

A support protrusion 24 is formed at the other of the two axial ends of the outer tube 12, protruding radially inward and supporting the other of the two axial ends of the covering member 17 in the axial direction. The support protrusion 24 is formed by bending the other end of the outer tube 12 into a flange shape. The support protrusion 24 supports the other end of the covering member 17 in the axial direction via the end flange portion 31a of the end elastic body 31.

Hereinafter, the axial side where the fixing portion 23 of the outer cylinder 12 is located will be referred to as the upper side, and the axial side where the support protrusion 24 of the outer cylinder 12 is located will be referred to as the lower side.

In this embodiment, an orifice passage that connects the liquid chambers 14a, 14b is provided between the end elastic body 31 and the end surface of the covering member 17 facing the axial direction.
The orifice passage is provided in the upper end surface 17a of the covering member 17. The upper end surface 17a is a flat surface facing upward. The orifice passage may also be provided in the lower end surface 17b of the covering member 17.

The upper end of the covering member 17 is formed with a circumferentially extending main groove 19, a first communication opening 18 that opens into one of the liquid chambers 14a, 14b and the main groove 19, and a second communication opening 20 that opens into the other of the liquid chambers 14a, 14b and the main groove 19.
The main body groove 19 is formed in the upper end surface 17a of the covering member 17, and the first communication opening 18 and the second communication opening 20 open to the inner surface of the covering member 17. The upper end opening of the main body groove 19 is liquid-tightly closed by the end flange portion 31a of the end elastic body 31.

The covering member 17 includes a plurality of segments 15 separated in the circumferential direction, and the peripheral edges 15a of adjacent segments 15 abut against each other to form a cylindrical shape as a whole. The two segments 15 are formed to have the same shape and size. Alternatively, the covering member 17 may be configured to be integrally formed into a cylindrical shape as a whole.
The covering member 17 covers the entire periphery of the intermediate elastic body 32. The peripheral edge 15a of the divided body 15 is located at the center of the intermediate elastic body 32 in the circumferential direction.

The outer tube 12 is fitted onto the covering member 17, and the fixing portion 23 and the support protrusion 24 axially sandwich the covering member 17 via the end elastic body 31, thereby elastically connecting the outer tube 12 and the inner mounting member 11, and defining an orifice passage connecting the liquid chambers 14a, 14b between the end elastic body 31 and the upper end surface 17a of the covering member 17. The orifice passage connects the liquid chambers 14a, 14b through the first communication opening 18 and the second communication opening 20.
When vibration is input to this vibration-damping device 1, the elastic bodies 31, 32 elastically deform, causing the internal volume of each liquid chamber 14a, 14b to fluctuate, causing the liquid in the liquid chambers 14a, 14b to flow through the orifice passage and generate liquid column resonance, thereby damping and absorbing the vibration.

As described above, according to the vibration-damping device 1 of this embodiment, an orifice passage connecting each liquid chamber 14a, 14b is provided between the end elastic body 31 and the upper end surface 17a of the covering member 17, so that by pressing the end elastic body 31 against the upper end surface 17a of the covering member 17 while it is fitted into the outer tube 12, it is possible to reliably ensure sealing of the liquid flowing through the orifice passage.
This makes it possible to eliminate the need to, for example, increase the dimensional accuracy of the covering member 17 or to vulcanize-bond a sealing rubber film to other members such as the outer cylinder 12 in order to ensure the sealing of the liquid flowing through the orifice passage, thereby reducing manufacturing costs.

Next, a vibration isolation device 2 according to a second embodiment will be described with reference to FIG.
In the second embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted, and only the differences will be described.

In this embodiment, the covering member 17 includes a first divided body 28 and a second divided body 29 that are divided into two in the axial direction.
The first division 28 is provided above the second division 29. The first division 28 has an upper end surface 17a of the covering member 17, and the second division 29 has a lower end surface 17b of the covering member 17. The axial size of the first division 28 is smaller than the axial size of the second division 29. The first division 28 faces the end connecting portion 31b in the radial direction over almost the entire axial length.

The first divided body 28 is formed with a main body groove 19 and a first communication opening 18 similar to those in the first embodiment.
Of the two axial end portions of the second divider 29, a second main body groove 29a extending in the circumferential direction and a second communication opening 29c opening into the other liquid chamber 14b of the liquid chambers 14a, 14b and into the second main body groove 29a are formed in the upper end portion axially adjacent to the first divider 28. The second main body groove 29a is formed in an abutting surface (upper end surface) 29b of the second divider 29 that abuts against the first divider 28 in the axial direction.
The main body groove 19 and the second main body groove 29a are axially connected through a through hole (not shown) formed in the mating surface (lower end surface) 28b of the first partition 28, which is axially mated with the second partition 29.
The abutting surfaces 28b, 29b of the first divided body 28 and the second divided body 29 are flat surfaces facing the axial direction.

As described above, in the vibration-damping device 2 according to this embodiment, the covering member 17 comprises a first division 28 and a second division 29 that are divided into two axially, and the orifice passage is integrally provided between the end elastic body 31 and the upper end surface 17a of the first division 28, and between the abutting surfaces 28b, 29b of the first division 28 and the second division 29 that are abutted against each other in the axial direction. This makes it possible to easily ensure the length of the orifice passage while reliably ensuring the sealing of the liquid flowing through the orifice passage.

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

The end elastic body 31 does not need to be provided with the rigid plate 33, and the outer cylinder 12 does not need to be formed with the fixing portion 23 and the support protrusion 24.
In the second embodiment, the first divided body 28 may be made of a soft material that is softer and more elastic than the second divided body 29, such as elastomer or rubber.

In addition, the components in the above-described embodiments may be replaced with well-known components as appropriate, and the above-described embodiments and variations may be combined as appropriate, without departing from the spirit of the present invention.

1, 2: Vibration isolation device 11: Inner mounting member 12: Outer cylinder 14a, 14b: Liquid chamber 17: Covering member 17a: Upper end surface (end surface)
26c: recess 28: first divided body 28b, 29b: butting surface 29: second divided body 31: end elastic body (elastic body)
32 Medium elastic body (elastic body)
O center axis

Claims (2)

an inner mounting member connected to one of the vibration generating unit and the vibration receiving unit, and an outer cylinder connected to the other and surrounding the inner mounting member;
an elastic body that elastically connects the inner mounting member and the outer cylinder,
the elastic body includes intermediate elastic bodies disposed on both sides of the inner mounting member in a radial direction intersecting the central axis line in a plan view seen from an axial direction along the central axis line of the outer cylinder,
a covering member is disposed between the inner mounting member and the outer cylinder, the covering member covering the spaces between the intermediate elastic bodies adjacent to each other in the circumferential direction around the central axis in the plan view from the outside in the radial direction and defining a liquid chamber between the inner mounting member and the intermediate elastic bodies;
the elastic body includes a pair of end elastic bodies that are arranged at an interval in the axial direction, are fitted into the outer cylinder, and sandwich the covering member in the axial direction;
An anti-vibration device in which a groove formed on an end surface of the covering member facing the axial direction is liquid-tightly blocked by the end elastic body, thereby providing an orifice passage connecting each of the liquid chambers between the end elastic body and the end surface of the covering member facing the axial direction. the covering member includes a first divided body and a second divided body that are divided into two in the axial direction,
The vibration-damping device described in claim 1, wherein the orifice passage is provided between the end elastic body and the end face facing the axial direction of the first division by liquid-tightly blocking a groove formed in the end face facing the axial direction of the first division with the end elastic body, and is provided between the butting surfaces of the first division and the second division, which are butted together in the axial direction, by liquid-tightly blocking a groove formed in the end face facing the axial direction of one of the first division and the second division with the other of the first division and the second division.