JP2000320603A - Liquid-sealed vibration control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate the connecting work of a fluid passage and to broaden the damping characteristics, when a fluid passage joined at a joining part of each circular arc-like member is provided, in a liquid-sealed vibration control device, in which a pair of circular arc-like grooves separated with an elastic partitioning wall is covered with a ring member. SOLUTION: A pair of circular arc-like grooves 4, 5 are provided on the outer peripheral part of an elastic vibration control member interposed between an outer cylinder 1 and an inner member 2 arranged concentrically. Both grooves 4, 5 are separated with elastic partitioning walls 6, 7 extending in the opposite directions, with the inner member 2 between them, and respective circular arc-like grooves 4, 5 are fitted to circular arc-like members 8, 9. The circular arc-like members 8, 9 form a continuous ring shape by joining adjacent connecting surfaces 12, 13. At the joint-end part in the vicinity of this joining part, a large fluid passage 14 and a small fluid passage 15 are formed, and the fluid passages 14, 15 are communicated at the joining part of the connecting surfaces 12, 13, in a large passage and small passage state.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid-sealed vibration isolator suitable for use in a subframe mount for an automobile or the like.

[0002]

2. Description of the Related Art In Japanese Patent Publication No. 7-99187, an inner tubular fitting and an outer tubular fitting are arranged inside and outside, and these fittings are connected to each other by a rubber elastic body. And, a pair of liquid chambers partitioned by a pair of partition walls formed sandwiching the inner cylindrical metal fittings are provided, and the openings of these liquid chambers are further covered with a pair of ring-shaped semi-circular members at the time of assembly. A liquid seal vibration isolator is shown in which the liquid chambers communicate with each other through an orifice passage formed by a fluid passage formed in advance in these semicircular members.

As an orifice passage structure in such a liquid-sealed vibration isolator, for example, Japanese Patent Laid-Open No. 6-3074 is disclosed.
No. 93 shows a configuration in which a fluid passage is formed in the outer peripheral portion of each semicircular arc-shaped member, and when the respective connection ends are connected by a connection surface, the respective fluid passages are simultaneously connected at this joint. Have been.

[0004]

By the way, as in each of the above-mentioned conventional examples, a case is adopted in which a pair of semicircular members or a plurality of divided circular members are combined in a ring shape to cover the liquid chamber. As described in Japanese Patent Application Laid-Open No. Hei 6-307493, a structure for connecting the respective fluid passages formed at the joints of the two semicircular members may be required.

[0005] In such a case, however, the fluid passages must be accurately connected to each other at the connection portions of the arc-shaped members. High component accuracy and assembly accuracy are required, resulting in lower productivity and higher cost. Further, it is desired that the orifice passage be broadened so that a damping effect can be obtained in a wide frequency band. Then, this invention aims at solving such a problem.

[0006]

According to a first aspect of the present invention, there is provided a liquid ring vibration isolator according to the present invention, comprising: a cylindrical outer cylinder and an inner cylinder disposed at a concentric or eccentric position inside the outer cylinder; A member and an elastic vibration isolating member interposed between the outer cylinder and the inner member, are opened radially outward around the elastic vibration isolating member, and extend radially outward from the inner member side. A plurality of arc-shaped grooves defined by elastic partition walls formed so as to form a liquid chamber in which a liquid is sealed, and the opening of each of the arc-shaped grooves is formed by a continuous ring during assembly. The adjacent liquid chambers are covered by orifice passages formed by connecting a pair of fluid passages which are formed by connecting a pair of fluid passages which are formed by connecting to a pair of fluid passages which are formed by opening the connection surfaces of the adjacent arc-shaped members. In the liquid seal vibration isolator, Fluid passages, one large and formed so as to become smaller and the other at a connection portion, characterized in that different fluid passage to the magnitude was communicatively connected.

[0007] A second invention is the first invention, wherein
The fluid passage has a groove shape that is open to a connection surface at each connection end of an adjacent arc-shaped member and another surface continuous with the connection surface.

[0008] In a third aspect based on the first aspect,
The fluid passage is formed of a hole formed in the wall thickness near the connection end of each arc-shaped member, and both ends thereof are respectively opened to the connection surface and the surface facing the liquid chamber.

[0009] In a fourth aspect based on the first aspect,
The distal end portion, which is the radially outer end of the elastic partition wall, is fitted into a concave portion formed across the connecting portion on the inner peripheral surface side of the adjacent arc-shaped member, and this fitting portion is connected to the distal end portion. And the fluid passage is formed in the arc-shaped member so as to bypass the distal end of the elastic partition wall.

[0010]

According to the first aspect of the present invention, the fluid passages constituting the orifice passages are provided in the vicinity of the respective connection ends of the adjacent arc-shaped members, and the fluid passages are combined in a large and small size to reduce the large ones. Because I was connected to
Connection is much easier than when fluid passages of the same size are connected.

As a result, the precision of the parts and the precision of the assembly can be greatly reduced, the production and the assembly work of the parts can be facilitated, the productivity can be improved and the cost can be reduced. Further, since the orifice passage is formed by combining large and small fluid passages, the damping characteristic of the orifice passage is broadened and a damping effect is obtained in a wider frequency band as compared with the case where only the small fluid passage is formed. be able to.

According to the second aspect of the present invention, since the fluid passage is formed as a groove that opens to the connecting surface of the arc-shaped member and any one of the surfaces following the connecting surface, the fluid passage can be formed simultaneously with the molding of the arc-shaped member. Man-hours can be reduced.

According to the third aspect of the present invention, since the fluid passage is formed in the shape of a hole in the thickness of the arc-shaped member, the influence of the elastic deformation of the elastic partition wall on the passage sectional area of the fluid passage can be eliminated.

According to the fourth aspect of the present invention, since the distal end of the elastic partition wall is fitted into the recess formed in the arc-shaped member, the distal end of the partition wall can be positioned and the distal end of the elastic partition wall can be positioned. Since the fluid passage is provided on the side of the arc member bypassing the above, the influence of the elastic deformation of the elastic partition wall can be avoided. Further, the distal end portion of the elastic partition wall abuts on the connection portion of the adjacent arc-shaped member, which is a portion where the pair of fluid passages are connected, and is fitted with the seal projection into the concave portion, so that the adjacent liquid chambers are provided. The gap can be efficiently and reliably sealed.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a first embodiment configured as a subframe mount of an automobile will be described with reference to FIGS. This sub-frame mount is a vibration isolator provided between a sub-frame provided to support an engine or the like of an automobile and a body frame.

FIG. 1 is a cross-sectional view (a cross-sectional view corresponding to the line 1-1 in FIG. 3) passing through the liquid chamber of the subframe mount, FIG. 2 is a top view thereof, and FIG. 3 is a cross-sectional view taken along a line 3-3 in FIG. FIG. 4 (sectional view is omitted), FIG. 4 is a sectional view taken along line 4-4 in FIG. 2 (same), FIG. 5 is an explanatory view of the assembly, FIG. 6 is an explanatory view of mounting of the arc-shaped member, and FIG. FIG.

First, the schematic structure of the subframe mount will be described. As shown in FIGS. 3 to 5, the sub-frame mount is composed of an outer cylinder 1 made of a suitable metal, an inner member 2 made of a similar material and concentrically or eccentrically arranged inside and appropriately formed in a cylindrical shape. And an elastic vibration isolating member 3 made of an appropriate known material such as rubber or elastomer which elastically connects the members with each other.

A pair of semicircular arc-shaped grooves 4 and 5 are formed around the generally cylindrical elastic vibration isolating member 3 in the radial direction of the elastic vibration isolating member 3 (hereinafter simply referred to as radial direction). ) Formed open to the outside, each of which is an inner member 2
A pair of elastic partition walls 6 extending to the opposite side in the radial direction with the
7 (FIG. 3), and each arc-shaped groove 4,
5 are fitted with arc-shaped members 8 and 9, whereby the liquid chamber 1 is
0 and 11 are formed (FIG. 4).

A known incompressible liquid is sealed in the liquid chambers 10 and 11 and formed at the respective ends of the arc-shaped members 8 and 9 in the vicinity of the opposing connection surfaces 12 and 13. The fluid passages 14 and 15 communicate with each other.
15 constitutes one orifice passage.

The arc-shaped members 8 and 9 correspond to one ring divided into two parts, and are connected to each other at their ends to form one continuous ring-shaped arc-shaped groove 4 or 5. It covers each opening and is attached around the elastic vibration isolating member 3.

As is apparent from FIG. 1, no fluid passages are formed at the connection ends near the connection surfaces 16, 17 on the other side of the arc-shaped members 8, 9, and the liquid chambers 10, 11 are formed. There is no communication at this point. However, if necessary, the same ones as the fluid passages 14 and 15 can be provided.

As shown in FIG. 5, these arc-shaped members 8,
9 is attached to the elastic vibration isolating member 3, the sub-assembly 18 is press-fitted into the outer cylinder 1, and a projection 19 provided at one end of the outer cylinder 1 and the other end are caulked to form a sub-frame integrated as a whole. It becomes a mount (Figs. 3 and 4).

In this sub-frame mount, as shown in FIG. 1, elastic partition walls 6 and 7 are arranged toward the left and right sides of the vehicle body, and when used in this state, the fluid passages 14 and 15 through the liquid chambers 10 and 11 are used. Form an orifice passage, so that longitudinal vibration is attenuated by liquid column resonance in the orifice passage.

Further, the volumes of the liquid chambers 10 and 11 change due to the elastic deformation of the elastic partition walls 6 and 7 due to the vibration in the front-rear direction, and the liquid in the liquid chambers 10 and 11 changes with the volume fluctuation at that time. By moving between the fluid passages 14 and 15, attenuation is absorbed. Further, when vibration in the left-right direction is applied, fluid movement between the liquid chambers 10 and 11 is not involved, and the elastic partition walls 6 and 6 are not involved.
This is absorbed by the elastic deformation of 7 and the elastic deformation of the whole vibration-proof elastic member 3.

Next, details will be described with reference to FIGS. The elastic vibration isolating member 3 is formed integrally with the inner member 2 around the inner member 2. At this time, the arc-shaped grooves 4 and 5 and the elastic partition walls 6 and 7 are integrally formed, and the radially inner side of the elastic partition walls 6 and 7 is formed. The ends are integrated with the inner member 2, and the other end portions 6a and 7a on the radially outer end side are free before assembly.

However, as shown in FIG. 1, the tip portions 6a, 7a
During the assembling, the assembling portions are positioned by fitting into the concave portions formed by the step portions 20 and 22 and the step portions 21 and 23 formed near the joining portions of the arc-shaped members 8 and 9 respectively. Tip portions 6a, 7a
Around the periphery, seal projections 7b are formed in advance as shown in the enlarged portion in the figure, and the front ends come into contact with the front and rear liquid chambers 10, 11 in a state where they are liquid-tightly fitted to the arc-shaped members 8, 9 side. It is designed to partition between. Although not shown, the distal end portion 6a also has a similar sealing structure.

Each of the arc-shaped members 8 and 9 is made of an appropriate material harder than the elastic vibration isolating member 3 such as plastic or metal. In this embodiment, each of the arc-shaped members 8 and 9 is formed into a substantially semicircular shape by molding using plastic. The elastic anti-vibration member 3 is formed in an arc shape and fitted into the open portions of the arc-shaped grooves 4 and 5 from the outside in the radial direction to form a single ring and covers the open portions of the arc-shaped grooves 4 and 5. It has a shape and dimensions that can be used.

The connection surfaces 12 and 16 at both ends of the arc member 8 are connected to the connection surfaces 1 at both ends of the arc member 9 respectively.
3 and 17, and stepped portions 20, 21, 22, and 23 are formed on the inner peripheral sides of both ends of each of the arc-shaped members 8, 9, and the connecting surfaces 12 and 16 are joined by the stepped portions 20 and 22. One recessed portion is formed across the portions so that the tip portion 6a can be fitted, and the step portions 21 and 23 also have one recessed portion capable of fitting the tip portion 7a.

The connecting ends of the arc-shaped members 8 and 9 provided with the steps 20 and 22 are connected to the steps 20 and 22 respectively.
Fluid passages 14 and 15 are provided substantially along 22.
These fluid passages 14 and 15 can be formed simultaneously with the formation of the arc-shaped grooves 8 and 9 on the mold surfaces of the respective molds when the arc-shaped grooves 8 and 9 are formed.

Each of the fluid passages 14 and 15 is provided with a step 2
0, 22 and extends in the circumferential direction and has one end
2 and 13 and a portion that bends at the other end and extends inward, with one end open to the liquid chamber 10 or 11.

As is apparent from FIG. 1, the fluid passage 14 provided in the arc-shaped member 8 is large, and the fluid passage 15 provided in the arc-shaped member 9 is of a small and large combination. In the section, the fluid passages 14, 15
Are connected in a state where they are different in size.

As shown in FIG. 6, the fluid passage 14 is formed in a groove shape which is open to the upper surface 8a in the figure and which is engraved into the wall from above. The arc-shaped member 8
In the figures, the upper surface is 8a, the inner surface is an inner surface 8b, the lower surface is 8c, and the outer surface is 8d. Each of these surfaces is four surfaces continuous with the connection surface 12.

Each surface of the arc-shaped member 9 is similarly expressed, and the fluid passage 15 of the arc-shaped member 9 is similarly formed. However, the fluid passage 15 has a magnitude relationship such that the fluid passage 15 is included in and overlaps with the fluid passage 15 as shown by a virtual line in a connection portion when the fluid passage 15 is connected to the fluid passage 14 in the lower part of FIG. And fluid passage 15
Are both smaller than the width W1 and the depth D1 of the fluid passage 14.

The height h of the elastic partition wall 6 is substantially the same as the height H of the arc-shaped member 8, and the outer end 6 of the elastic partition wall 6 has a height h.
a is lower by d than the outer peripheral surface of the elastic vibration isolating member 3, and this dimension d is substantially the same as the width W of the arc-shaped member 8. Further, seal projections 25 are formed integrally with the inner walls 3a and 3b of the elastic vibration isolating member 3 which surround the arc-shaped groove and oppose vertically in the illustrated state.

The seal projections 25 are formed at an interval wider than the width W1 of the fluid passage 14. On the side of the inner wall 3a which comes into contact with the upper surface 8a, when the arc member 8 is fitted into the arc groove 4, 14 are formed to seal along the open edge. The same applies to the seal structure for the fluid passage 15.

FIG. 7 shows a variation of the fluid passages 14 and 15, wherein the row A in the figure shows the fluid passage 1 on the arcuate member 8 side.
Rows 4 and B show the fluid passages 15 on the side of the arc-shaped member 9 as cross sections in the vicinity of the joint, respectively. The corresponding display surfaces of the rows A and B are aligned with the row B side. The positional relationship of the fluid passage 14 at the time of being overlapped is displayed on the fluid passage 15 with a virtual line.

First, A1 and B1 are formed so that the fluid passages 14 and 15 are opened to the outer surfaces 8d and 9d, and each of the fluid passages 14 and 15 communicates with the corresponding liquid chamber 10 or 11. For this purpose, a passage penetrating the arc-shaped members 8 and 9 in and out is provided by machining or the like. Also in this case, the orifice passage can be formed by the contact of the outer ends 6a and 7a. However, these fluid passages 14 and 15 may be formed on the inner surfaces 8b and 9b side.
A passage for communicating with 0 and 11 can be omitted.

A2 and B2 are provided so as to cut out the corners of the upper surface 8a and the outer surface 8d and the upper surface 9a and the outer surface 9d. Even when the thickness is small, the formation of the fluid passage becomes easy.

In this case, the other three corners can be similarly formed. However, in the illustrated example opened to the outer surface side, it is necessary to form a passage for connecting with the liquid chambers 10 and 11, and this passage is provided in FIGS.
As shown in FIG. 7, if the grooves are formed as passages open to the upper surfaces 8a, 9a, they can be formed simultaneously with the formation of the arc-shaped grooves 8, 9.
In addition, such a passage can be omitted when it is opened to the inner side.

A3 and B3 are formed as large and small holes penetrating through the thickness, and one end of each hole is connected to the connection surfaces 12 and 13.
The other end is bent to the inner peripheral side within the thickness and
b, 9b. The fluid passages 14 and 15 can be formed by a mold at the same time as the formation of the arc-shaped members 8 and 9, or can be partially or entirely formed by machining. In this case, the cross-sectional area of the fluid passage is not affected by the elastic deformation of the elastic partition walls 6, 7, and the like.

Note that reference numerals 8e and 9 shown in FIGS.
Reference numeral e denotes a positioning projection integrally formed at an appropriate position on the outer peripheral portions of the arc members 8 and 9, respectively, and formed on the outer peripheral portion of the elastic vibration isolating member 3 facing the arc grooves 4 and 5 when assembled. It fits into the positioning recess 3c (FIG. 4), and serves to prevent the rotation of the arc-shaped members 8, 9 in the circumferential direction of the elastic vibration isolating member 3.

Next, the operation of this embodiment will be described. To assemble the sub-frame mount, as shown in FIG. 5, the arc-shaped members 8, 9 are fitted into the arc-shaped grooves 4, 5, and the connection surfaces 12 and 13 and 16 and 17 are joined.
Then, the fluid passage 14 is formed at the junction of the connection surfaces 12 and 13.
And 15 are communicatively connected.

At this time, as is clear from FIGS. 1 and 6, the fluid passage 14 is formed as a combination of a large fluid passage 15 and a small fluid passage 15 so that the smaller fluid passage 15 is connected to the larger fluid passage 14 at the joint. Connected in a contained state.

Therefore, the elastic vibration isolating member 3 including the arc-shaped grooves 4 and 5 and the arc-shaped members 8 and 9 can be reliably communicated without increasing the molding accuracy and the assembly accuracy as in the prior art. Molding and assembly conditions can be relaxed, parts can be easily manufactured and assembled, productivity can be improved, and costs can be reduced.

In addition, since there is no need to form a fluid passage on the side of the elastic partition walls 6 and 7 as employed in a part of the conventional vibration isolator of this type, the elastic partition walls 6 and 7 and the elastic vibration isolator are not required. The influence of the cross-sectional area of the passage due to the elastic deformation of No. 3 can be reduced, and stable vibration isolation performance can be maintained.

In addition, the radial end portion 6 of the elastic partition wall 6
a and 7a are connecting surfaces 12 and 13 of adjacent arc-shaped members 8 and 9 which are portions where a pair of fluid passages 14 and 15 are connected.
At the same time, and is fitted into the recess formed by the step portions 20 and 22 with the seal projection 7b, so that the adjacent liquid chambers 10 and 11 can be efficiently and reliably sealed.

FIG. 9 is a diagram showing the damping characteristics obtained by the orifice passage of the present invention constituted by large and small fluid passages as in the present embodiment, and the solid line in the figure is obtained by the orifice passage of the present invention. The dashed line indicates the general tendency of the damping characteristic in the orifice passage constituted by only the fluid passage corresponding to the small fluid passage 15 as shown in the present embodiment.

As is apparent from this figure, while the damping characteristic of the orifice passage composed of a single fluid passage shown by a broken line has a relatively relatively steep curve, the damping characteristic of the orifice passage of the present invention is different. It forms a gentler plateau-like curve. This is a result of forming the orifice passage by combining the large and small fluid passages 14 and 15 according to the present invention, and shows that the damping effect by the liquid column resonance is obtained in a wider frequency band than the conventional case. . Therefore,
According to the present invention, the attenuation effect can be extended to a wider frequency band, that is, the attenuation characteristics can be broadened.

FIG. 8 is a schematic view showing a portion similar to FIG. 1 according to the second embodiment. In the following description, the first
The same parts as those in the embodiment are denoted by the same reference numerals.
In this example, the fluid passages 14 and 15 are formed as in the first embodiment, but the distal ends 6a and 7 of the elastic partition walls 6 and 7 are formed.
“a” has an acute angle shape that changes to a tapered shape in which the tip end side becomes thinner.

At the tip of the tip 7a, a seal projection 7c is formed as shown in the enlarged portion in the figure. The distal end portion 7a elastically deforms the seal projection 7c to be pressed against the inner peripheral surface near the connection end portion of the arc-shaped member 8 to be in contact therewith and slidable in a liquid-tight manner. The same applies to the tip 6a.

Each of the inner peripheral surfaces of the arc-shaped members 8, 9 in contact with the distal ends 6a, 7a in the vicinity of the connection ends is the first.
Without the concave portion as in the embodiment, the distal end portions 6a and 7a form a continuous and uniform curved surface with other portions so as to be slidable in a liquid-tight manner.
The connecting portions of the arc-shaped members 8 and 9 are located at positions displaced in the circumferential direction from the sliding range of the tip portions 6a and 7a.

By forming the outer ends 6a and 7a at acute angles in this manner, the elastic partitions 6 and 7 have a directionality to absorb the input vibration applied from the extending direction of the partition walls 6 and 7 and have a direction according to the magnitude of the input vibration. The spring rate can be changed, and the inner peripheral surfaces of the arc-shaped members 8 and 9 can be slid so that a low dynamic spring can be realized.

In addition, the sealing property of the sliding portion can be maintained at a high level by the seal projection 7c, the adjacent liquid chambers 10 and 11 can be reliably sealed, and the arc-shaped members 8, 9 and the elastic partitioning walls 6 or 7 can be sealed. Since it is not necessary to collectively connect the three members at one point, it becomes easier to join them in a liquid-tight manner.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view passing through a liquid chamber of a subframe mount according to a first embodiment.

FIG. 2 is a top view thereof.

FIG. 3 is a sectional view taken along line 3-3 in FIG. 2;

FIG. 4 is a sectional view taken along line 4-4 in FIG. 2;

FIG. 5 is an explanatory view of the assembly.

FIG. 6 is an explanatory view of mounting an arc-shaped member.

FIG. 7 is a view showing a variation of a fluid passage.

FIG. 8 is a schematic view showing a portion similar to FIG. 1 according to the second embodiment.

FIG. 9 is an attenuation characteristic diagram according to the present invention.

[Description of Signs] 1: Outer cylinder, 2: Inner member, 3: Elastic vibration isolator, 4: Arc groove, 5: Arc groove, 6: Elastic partition wall, 7: Elastic partition wall, 8: Arc shape Member, 9: arc-shaped member, 10: liquid chamber, 1
1: liquid chamber, 14: fluid passage, 15: fluid passage

Claims (4)

[Claims] 1. An elastic vibration isolator comprising: a cylindrical outer cylinder; an inner member disposed at a concentric or eccentric position inside the outer cylinder; and an elastic vibration isolating member interposed between the outer cylinder and the inner member. A plurality of arc-shaped grooves which are open radially outward and extend from the inner member side in a radial direction and are defined by elastic partition walls. Is a liquid chamber in which the liquid is sealed, and the open part of each arc-shaped groove is covered with a plurality of arc-shaped members forming a continuous ring shape at the time of assembly, and each of the connection surfaces of adjacent arc-shaped members is opened. In a liquid seal vibration isolator in which adjacent liquid chambers are communicated with an orifice passage formed by connecting a pair of formed fluid passages, the pair of fluid passages that are connected to each other have one larger at a connection portion and The other is formed to be smaller and this Liquid sealed vibration isolating device which is characterized in that is communicatively connected to different fluid passage small. 2. The fluid passage according to claim 1, wherein each of the fluid passages has a groove shape open to a connection surface at each connection end of the adjacent arc-shaped member and another surface continuous with the connection surface. 2. The liquid-sealed vibration isolator according to 1. 3. The fluid passage comprises a hole formed in a wall thickness near a connection end of each arc-shaped member, and both ends thereof are respectively opened on a connection surface and a surface facing the liquid chamber. The liquid-sealed vibration isolator according to claim 1, wherein: 4. A distal end portion of the elastic partition wall, which is an outer end in the radial direction, is fitted into a concave portion formed over a connecting portion on the inner peripheral surface side of an adjacent arc-shaped member, and this fitting is performed. And a fluid passage formed in the arc-shaped member so as to bypass the distal end of the elastic partition wall while sealing the portion with a seal projection provided in advance at the distal end. The described liquid ring vibration isolator.