JP2955304B2 - Bushing type vibration damping device with liquid - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a liquid-containing bush type vibration damping device in which a liquid chamber is provided in an elastic body interposed between inner and outer cylinders.

[Conventional technology]

As a vibration isolator used as an engine mount, a cabinet mount, a body mount, or the like of a vehicle, there is a so-called bush type vibration isolator in which an elastic body is interposed between inner and outer cylinders arranged in a parallel axis. In this vibration isolator, a hollow portion is provided through an inner cylinder in the elastic body, and a plurality of liquid chambers are provided. These liquid chambers are communicated via a restriction passage to improve the vibration isolating effect ( JP-A-1-182645).

By the way, as shown in FIG.
When is mounted on a vehicle or the like, it is press-fitted into a tubular portion 104 of a bracket 102 fixed to the vehicle or the like in advance.

An air hole 108 is formed in the cylindrical portion 104 of the bracket 102 so that the air chamber 106 of the vibration isolator 100 can communicate with the outside. For this reason, when the vibration isolator 100 is subjected to vibration and the diaphragm 110 is deformed toward the outer cylinder 112 (downward in FIG. 7), the diaphragm 110 is moved to the edge of the air hole 108.
There is a problem that the diaphragm 110 is scratched due to strong contact with the 108A, and as a result, the durability of the vibration isolator 100 is short. In order to solve this, the diaphragm 110 must be made thick or a special material must be used.

[Problems to be solved by the invention]

The present invention has been made in view of the above-described circumstances, and has as its object to provide a bush-type vibration damping device capable of extending the durability of a diaphragm.

[Means for solving the problem]

According to the invention described in claim (1), the elastic body is interposed between the inner and outer cylinders arranged in a parallel shaft shape, the elastic body is provided with a liquid chamber, and the outer cylinder communicates with the outside on the inner peripheral surface of the inner cylinder. What is claimed is: 1. A bush type vibration damping device containing a liquid used in a state of being inserted into a mounting member having a hole, provided between the inner cylinder and the outer cylinder to form an outer wall of the liquid chamber and expand and contract the liquid chamber. A diaphragm that is deformable in the direction and forms an air chamber inside the outer cylinder, a notch formed in a portion of the outer cylinder corresponding to the diaphragm, and not facing the air hole, and an outer periphery of the outer cylinder. And a passage that is recessed inward from the outer peripheral surface of the outer cylinder and extends from the end of the notch, is connected to the air chamber, and faces the air hole. Features.

[Action]

According to the first aspect of the present invention, the vibration isolator is press-fitted into a mounting member such as a bracket, and the passage formed in the outer peripheral portion of the outer cylinder corresponds to the air hole formed in the bracket. Then, vibration is applied to the vibration isolator, and even if the diaphragm is deformed in the direction of the outer cylinder, contact with the air holes formed in the bracket is prevented.

Further, since the air chamber of the vibration isolator communicates with the outside through the passage and the air holes of the bracket, the deformation of the diaphragm is not limited.

〔Example〕

1 to 6 show a vibration isolator 10 to which the present invention is applied.
One embodiment is shown.

As shown in FIGS. 1 and 2, in this vibration isolator 10, an inner cylinder 12 and an outer cylinder 14 are arranged in a parallel axis shape, and one of the inner cylinder 12 and the outer cylinder 14 is vibrated by a vehicle engine or the like and the other is vibrated. It is adapted to be connected to a vehicle body or the like as a receiving portion.

In this embodiment, a bracket in which the outer cylinder 14 is fixed to a vehicle
The tube 90 is inserted into and supported by a tubular portion 92 (shown in FIG. 6). As shown in FIG. 6, an air hole 94 is formed through the cylindrical portion 92 of the bracket 90 in the radial direction of the cylindrical portion 92.

As shown in FIGS. 1 and 2, an intermediate cylinder 18 is disposed between the inner cylinder 12 and the outer cylinder 14 so as to be parallel to the inner cylinder 12.

As shown in FIG. 3, a thin rubber 16 is vulcanized and bonded in the circumferential direction at the center of the inner peripheral surface of the outer cylinder 14.
Are convex toward the inner cylinder 12, and constitute a diaphragm 16A.

The outer cylinder 14 side of the diaphragm 16A is an air chamber 17, so that the deformation of the diaphragm 16A can be allowed.

As shown in FIG. 1, a main rubber 20 as an elastic body is stretched between the intermediate cylinder 18 and the inner cylinder 12.

A metal fitting 24 is provided at an axially intermediate portion of the inner cylinder 12.
For this reason, the main rubber 20 corresponding to the metal fitting 24 projects in the radial direction of the inner cylinder 12 (downward in FIG. 1) to serve as a stopper.

Further, a cavity 22 communicated in the axial direction is formed between the main rubber 20 and the intermediate cylinder 18 (upper side in FIG. 1) so that the inner cylinder 12 can be moved.

A liquid chamber 26 is provided on the opposite side (lower side in FIG. 1) of the hollow portion 22 via the inner cylinder 12, and a liquid such as water or oil is sealed therein.

The liquid chamber 26 is formed by cutting the main rubber 20 from the outer peripheral portion toward the inner cylinder 12. Specifically, when the main rubber 20 is formed, a mold corresponding to the size of the liquid chamber 26 ( Is formed by inserting the core into the mold.

The liquid chamber 26 has a part of the outer wall constituted by the diaphragm 16A.

A partition plate 28 having a substantially hat-shaped cross section is inserted into the liquid chamber 26 to divide the liquid chamber 26 into small liquid chambers 26A and 26B.

The flange portion 28A of the partition plate 28 is sandwiched between the intermediate cylinder 18 and the diaphragm 16A.

As shown in FIG. 1, the center of the partition plate 28 is inserted into the liquid chamber 26 through a notch 18A provided in the intermediate cylinder 18, and the vicinity of the notch 18A is The cross section is approximately L so as to limit the amount of movement of the outer peripheral portion in the direction of the inner cylinder 12
It is a character-shaped bent portion.

As shown in FIG. 3, a substantially C-shaped concave portion 30 is formed at the axial center of the intermediate cylinder 18 when viewed from the axial direction.

Rubber 31 is vulcanized and bonded to both sides of the recess 30 in the axial direction of the intermediate cylinder 18.

The concave portion 30 forms a restriction passage 32 between the elastic film 16 and the elastic film 16 as shown in FIGS. 1 and 2 after the assembly.

As shown in FIG. 2, the restriction passage 32 circulates in a substantially C shape inside the outer cylinder 14, and one end 32A in the longitudinal direction is
The other end 32B communicates with the small liquid chamber 26A via a concave part 28B formed in a part of the small liquid chamber 8 and the other end 32B.

As shown in FIG. 3, grooves 40 are formed in both ends in the axial direction of the intermediate cylinder 18 in the circumferential direction. An O-ring 42 is provided in the groove 40 to enhance the sealing performance of the restriction passage 32.

As shown in FIG. 4, a rectangular cutout 44 having a long side in the circumferential direction and a short side in the axial direction is formed in a portion of the outer cylinder 14 corresponding to the diaphragm 16A of the elastic film 16.

At the center of the notch 44 is a column that straddles the outer cylinder 14 in the axial direction.
46 is bridged, dividing notch 44 into two small notches.

As shown in FIG. 2, rubber 50 is vulcanized and bonded to the inner peripheral surface of the column portion 46 so that the diaphragm 16A is deformed and abutted against the column portion 46 so that the diaphragm 16A is not damaged. Has become.

In addition, as shown in FIG. 4, a rectangular passage 52 long in the circumferential direction of the outer cylinder 14 is formed on the outer peripheral surface of the column portion 46.

This passage 52 is concave in the direction of the inner cylinder 12.

For this reason, as shown in FIG. 5, when the vibration isolator 10 is pressed into the cylindrical portion 92 of the bracket 90 of the vehicle body, a gap is formed between the inner peripheral surface of the cylindrical portion 92 and the passage 50. Since the air chamber 17 of the vibration isolator 10 is formed and communicates with the outside air through the passage 50 and the air hole 94 of the bracket 90, the deformation of the diaphragm 16A is not limited.

 Next, a method of manufacturing the vibration isolator 10 of the present embodiment will be described.

First, the main rubber 20 is vulcanized and bonded between the inner cylinder 12 and the intermediate cylinder 18. The main rubber 20 has a concave portion for forming the liquid chamber 26 corresponding to the notch 18A of the intermediate cylinder 18.

On the other hand, the outer cylinder 14 is vulcanized and bonded to the inner peripheral surface of the outer cylinder 14.
In this case, a concave diaphragm 16A is formed in the rubber 16,
The diaphragm 16A is made to correspond to the notch 44 of the outer cylinder 14.

Therefore, this diaphragm 16A is not vulcanized and bonded.

Here, when the inner cylinder 12 and the intermediate cylinder 18 are inserted into the outer cylinder 14 in the liquid, the liquid is filled into the liquid chamber 26 and the restriction passage 32.

In this case, by making the inner diameter of the rubber 16 larger by about 2 mm than the outer diameter of the main body, that is, the intermediate cylinder 18, both can be easily assembled.

Further, since the rubber 16 is vulcanized and adhered to the outer cylinder 14, the diaphragm 16A can be easily accommodated in the elastic concave portion of the main body with its assembly position around the axis and in the axial direction being accurate.

In this state, the vibration isolator 10 is completed by performing a squeezing process to reduce the outer diameter of the outer cylinder 14.

 Next, the operation of the present embodiment will be described.

When the vibration isolator 10 is press-fitted into the bracket 90, the air holes 94 of the bracket 90 correspond to the column portions 46 of the vibration isolator 10, and then the vibration isolator 10 is press-fitted into the cylindrical portion 92 of the bracket 90.

When the operation of press-fitting the vibration isolator 10 into the bracket 90 is completed, the air holes 94 provided in the cylindrical portion 92 of the bracket 90 correspond to the passages 52 of the column portions 46 of the vibration isolator 10.

For this reason, the vibration isolator 10 receives the vibration and the diaphragm 16
Even if A is deformed, the diaphragm 16A abuts the column 46,
Contact with the air holes 94 is prevented.

For this reason, the diaphragm 16A does not come into contact with the edge of the air hole 94, so that the diaphragm 16A is not damaged.

Moreover, since the air chamber 17 of the vibration isolator 10 communicates with the outside through the passage 52 and the air hole 94 of the bracket 90, the deformation of the diaphragm 16A is not limited.

The column 46 provided on the outer cylinder 14 is
When the vibration isolator 10 is press-fitted into the 90, it also has a function of suppressing deformation of the outer cylinder 14.

That is, by this press-fitting, as shown in FIG.
A frictional force is generated between the outer peripheral surface of the outer cylinder 14 of FIG. 10 and the inner peripheral surface of the cylindrical portion 92 of the bracket 90, and a compressive force in the directions indicated by arrows M and N acts on the notch 44 of the outer cylinder 14. .

However, since the column portion 46 is formed in the notch 44 of the outer cylinder 14 to increase rigidity, even when a compressive force is applied to the vicinity of the notch 44 of the outer cylinder 14 when the bracket 90 of the vibration isolator 10 is press-fitted, the outer portion 14 is not removed. The possibility that the cylinder 14 is deformed is small.

For this reason, the diaphragm 16A is pulled in the axial direction of the outer cylinder 14 due to the deformation of the outer cylinder 14, and the characteristics and durability are reduced.
It is possible to prevent the sealing property of 10 from being lowered.

In the above embodiment, the pillar 46 is formed integrally with the outer cylinder 14 in the axial direction.However, the pillar 46 is formed in the circumferential direction of the outer cylinder 14 so as to bridge the notch 44. You may.

〔The invention's effect〕

As described above, in the present invention, if the vibration isolator is press-fitted into a mounting member such as a bracket, and the passage formed in the outer peripheral portion of the outer cylinder and the air hole formed in the bracket correspond to each other, Even if vibration is applied to the vibration isolator and the diaphragm is deformed in the direction of the outer cylinder, the diaphragm is prevented from contacting the air holes formed in the bracket.

For this reason, the diaphragm does not come into contact with the air holes and is not damaged, thereby providing an excellent effect that the durability of the vibration isolator is improved.

[Brief description of the drawings]

1 to 6 show an embodiment of a vibration isolator according to the present invention. FIG. 1 is a sectional view taken along the line II of FIG. 2, and FIG.
FIG. 3 is an exploded perspective view, and FIG.
FIG. IV is a bottom view as seen from the direction of the arrows, FIG. 5 is a partially enlarged view of FIG. 2 in a state where the vibration isolator is pressed into the bracket, and FIG. 6 is a press fit of the vibration isolator into the bracket. A bottom view on the way,
FIG. 7 is a sectional view of a state in which the conventional vibration isolator is pressed into a bracket. 10 ... Bushing type vibration damping device with liquid, 12 ... Inner cylinder, 14 ... Outer cylinder, 16A ... Diaphragm, 20 ... Body rubber (elastic body), 26 ... Liquid chamber, 44 ... Notch (Notch) Part), 46 ... pillar part, 52 ... passage, 56 ... cushion rubber (buffer), 58 ... through hole.

Claims (1)

(57) [Claims] 1. An attachment member having an elastic body interposed between an inner and an outer cylinder arranged in a parallel axis shape, a liquid chamber provided in the elastic body, and an outer cylinder having an air hole in an inner peripheral surface thereof communicating with the outside. A bush type vibration damping device containing liquid used in an inserted state, wherein the device is provided between the inner cylinder and the outer cylinder to form an outer wall of the liquid chamber and to be deformable in a direction in which the liquid chamber expands and contracts. A diaphragm forming an air chamber inside the outer cylinder; a notch formed in a portion of the outer cylinder corresponding to the diaphragm, not facing the air hole; A liquid recessed bush that is recessed inward from the outer peripheral surface of the outer cylinder, extends from the end of the cutout, is connected to the air chamber, and faces the air hole. Type vibration isolator.