JPH0565937A - Vibration control equipment - Google Patents

Abstract

PURPOSE:To improve a vibration control characteristic by increasing the capacity of liquid chambers without enlarging the dimensions of a vibration control equipment. CONSTITUTION:In an intermediate cylinder 30 made of a die-cast aluminum alloy, the outer cylinder 1 side corner part of a large diameter part 36 is formed into an acute angle. The axial measure C of a main liquid chamber 64 and the axial measure D of an auxiliary liquid chamber 50 can be thereby made larger compared to an existing vibration isolator in which the outer cylinder side corner part of the large diameter part is formed into R-shape, so that the maximum capacity of the auxiliary liquid chamber 50 and main liquid chamber 64 can be secured. With the enlargement of the axial measure D of the auxiliary liquid chamber 50, the area of a diaphragm corresponding to the auxiliary liquid chamber 50 can be also enlarged, and the durability of the diaphragm can be improved by suppressing the deformation quantity of the diaphragm at the vibration input time.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid-filled type vibration damping device which is used for engine mounts, roll stoppers, bushes and the like of vehicles and absorbs and dampens vibrations from vibration generating parts.

[0002]

2. Description of the Related Art An engine of a car is provided with an anti-vibration device as an engine mount between the engine and the vehicle body.
The engine vibration is prevented from being transmitted to the vehicle body. As this type of vibration damping device, a liquid-filled type vibration damping device having an intermediate cylinder has been proposed.

As shown in FIGS. 4 and 5, a thin rubber layer 114 is vulcanized and adhered to the inner peripheral surface of an outer cylinder 112 of the vibration isolator 100, and a part of the thin rubber layer 114 is located inside. The diaphragm 116 is formed by projecting. This outer cylinder 1
Reference numeral 12 is inserted and fixed in a bracket 113 for mounting a vehicle body or the like. Inside the outer cylinder 112, the intermediate cylinder 1
18 are arranged, and the inner cylinder 120 is arranged in the same direction inside the intermediate cylinder 118. An elastic body 122 is bridged between the intermediate cylinder 118 and the inner cylinder 120,
The elastic body 122 is vulcanized and bonded to the inner peripheral surface of the intermediate cylinder 118 and the outer peripheral surface of the inner cylinder 120.

Ring-shaped large-diameter portions 124 are formed at both axial ends of the intermediate cylinder 118. As shown in FIG. 4, the radial outer peripheral surfaces of the large-diameter portions 124 are the outer cylinder 1 described above.
Twelve thin rubber layers 114 are closely attached. Further, the axially intermediate portion of the intermediate cylinder 118 is reduced in diameter to form a small diameter portion 126. As shown in FIG. 5, a concave portion 130 is formed in a part of the small diameter portion 126, and the concave portion 130 and the outer cylinder 1 are formed.
A sub-liquid chamber 132 is provided between the sub-chamber 16 and the sub-chamber 16. In this intermediate cylinder 118, a pair of press-formed steel plates (such as a hot-rolled steel plate for automobile structure) intermediate cylinder components are opposed to each other and welded at the center of the small diameter portion 126.
On the inner and outer surfaces of 26, a part of the elastic body 122 is vulcanized and adhered to seal the welded portion 128 in order to improve the reliability of hermeticity.

Further, the elastic body 122 is formed with a recess 134 on the side opposite to the recess 130 with the inner cylinder 120 interposed therebetween, and the recess 134 has a semicircular arc-shaped restricting passage forming member 136 when viewed in the axial direction. Are arranged. As shown in FIG.
The longitudinal section of the restricted passage forming member 136 is substantially hat-shaped. Flange portion 13 of the restricted passage forming member 136
6A, a reduced diameter portion 124A is formed on the large diameter portion 124 of the intermediate cylinder 120, and the thin-walled elastic body 122 is vulcanized and adhered to the radially outer peripheral surface of the reduced diameter portion 124A. There is.

The flange portion 13 of the restricted passage forming member 136
6A is an elastic body 12 between the reduced diameter portion 124A and the outer cylinder 116.
2 and the thin rubber layer 120, the bottom surface portion 138 of the restricted passage constituting member 136 is in close contact with the small diameter portion 126 through the thin elastic body 122 at both longitudinal ends.

The limiting passage forming member 136 and the concave portion 134
A main liquid chamber 140 is formed between the and. As shown in FIG. 5, the groove 142 of the restricted passage constituting member 136 constitutes a restricted passage 144 between itself and the outer cylinder 112.
One end of 44 is connected to the sub liquid chamber 132, and the other end is connected to the main liquid chamber 140 via the opening 148.

[0008]

By the way, in the vibration isolator 100, the radial outer peripheral surface of the large diameter portion 124 of the intermediate cylinder 118 is brought into close contact with the thin rubber layer 114 on the inner peripheral surface of the outer cylinder 116. A seal is made to prevent the liquid inside from flowing out. Here, in order to prevent the liquid from flowing out, as shown in FIG. 4, the large diameter portion 124 and the thin rubber layer 114 are provided.
It is necessary to secure the length A of the close contact portion with, that is, the length of the seal portion as long as possible. Further, in order to ensure the durability of the diaphragm 116, it is necessary to make the volume of the sub liquid chamber 132 as large as possible to make the area of the diaphragm 116 large (if the area of the diaphragm 116 is made large, the sub liquid at the time of vibration). The deformation amount of the diaphragm 116 can be reduced with respect to the volume change of the chamber 132, the stress acting on the diaphragm 116 is reduced, and the diaphragm 116 does not contact the bracket 113). It is desirable to make the length D of D as long as possible. In addition, the length C of the main liquid chamber 140 also needs to be increased in order to increase the capacity (in order to increase the capacity of the liquid chamber to allow a large amount of liquid to flow back and forth in the restriction passage and increase the loss coefficient). Further, the width B of the reduced diameter portion 124A needs to be long in order to sandwich and fix the restricted passage forming member 136 with the outer cylinder 112.

By the way, the intermediate cylinder 1 of the vibration isolator 100
18 is made by press molding, and the outside of the bent portion is R-shaped (see FIG. 4). Generally, 90
When bent at an angle of R, the radius R on the outside of the bent portion has a radius of at least about 1.5 times the plate thickness. For example, the intermediate cylinder 1
When 30 is formed of a steel plate having a plate thickness of 2 mm, R on the outer side of the bent portion is at least 3 mm or more.

However, as shown in FIG. 4, the R on the outside of the bent portion of the intermediate cylinder 130 is unnecessary in a limited size (the axial length L of the vibration isolator 10). Recognize. That is, if the shape on the outside of the bent portion is an acute angle, the length C of the main liquid chamber 140 and the length D of the sub liquid chamber 132 can be increased without changing the length A of the contact portion. Although it is conceivable to cut the rod material to form the intermediate cylinder 118, the number of cut portions is large and the manufacture is complicated.

Further, since the outer periphery of the intermediate cylinder 118 is circular, when the elastic body 122 is vulcanized and bonded to the intermediate cylinder 118, the intermediate cylinder 118 rotates in the axial direction in the mold for vulcanization molding. There is a possibility that the thickness of the elastic body 112 that covers the small diameter portion 126 (including the concave portion 130) may be partially reduced, and the sealing performance may be deteriorated.

In consideration of the above facts, an object of the present invention is to obtain a vibration isolator capable of increasing the capacity of the liquid chamber and improving the characteristics without increasing the size of the vibration isolator.

[0013]

SUMMARY OF THE INVENTION The present invention has a plurality of liquid chambers connected by a restricting passage, is arranged in an outer cylinder, constitutes a part of a partition wall of the liquid chamber, and is formed in the outer cylinder. A liquid-filled type vibration damping device comprising an intermediate cylinder that is in close contact with the inner peripheral surface to prevent the liquid from leaking out, wherein the intermediate cylinder is brought into contact with the inner peripheral surface of the outer cylinder to leak out the liquid. It is characterized in that it is made of a molding die in which the corner portion of the contact surface of the intermediate cylinder for preventing the above is formed at an acute angle.

[0014]

According to the present invention having the above-mentioned structure, when vibration is input, the liquid moves back and forth between the liquid chambers through the restriction passage to receive the passage resistance or resonate in the liquid column to absorb the vibration.

According to the present invention, since the intermediate cylinder is made of a molding die in which the corner portion of the contact surface that comes into contact with the inner peripheral surface of the outer cylinder to prevent the liquid from leaking out is formed into an acute angle, the contact of the intermediate cylinder is prevented. The corner of the contact surface is an acute angle and no R is attached. Therefore, in the case where the vibration isolator has the same axial length, the vibration isolator of the present invention has a shaft of the liquid chamber more than that of the conventional vibration isolator using the intermediate cylinder having R at the corners. The dimension in the direction can be increased by a length corresponding to the radius of the corner of the conventional intermediate cylinder. Therefore,
A large loss coefficient can be obtained by expanding the capacity of the liquid chamber and increasing the amount of the liquid flowing back and forth in the restriction passage during vibration.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a vibration isolator 10 according to the present invention will be described with reference to FIGS.

As shown in FIG. 1, the anti-vibration device 10 is provided with a mounting frame 12 for mounting on a vehicle body (not shown) such as an automobile. This mounting frame 1
2 is provided with an annular portion 14. As shown in FIG. 2, an outer cylinder 16 is inserted into the annular portion 14, and the outer cylinder 16 is fixed in the annular portion 14 by crimping both ends of the annular portion 14 inward.

As shown in FIG. 1, a pair of rectangular holes 18 are formed in the outer cylinder 16 along the circumferential direction, and a thin rubber layer 20 is vulcanized and adhered to the inner peripheral surface. As shown in FIG. 3, the thin rubber layer 20 has a portion corresponding to the rectangular hole 18 protruding inward to form a diaphragm 24. An air chamber 26 is formed between the diaphragm 24 and the annular portion 14. The air chamber 26 may have a hole formed in the annular portion 14 to communicate with the outside air.

As shown in FIGS. 1 and 2, a cylindrical block 28 is inserted inside the outer cylinder 16. This cylindrical block 28 is an intermediate cylinder 3 made of aluminum alloy die cast.
0, the elastic body 34, and the inner cylinder 22. The inner cylinder 22 is arranged inside the intermediate cylinder 30 in the same direction, and the elastic body 34 is bridged between the intermediate cylinder 30 and the inner cylinder 22. (See FIG. 3). The elastic body 34 is vulcanized and adhered to the inner peripheral surface of the intermediate cylinder 30 and the outer peripheral surface of the inner cylinder 22.

As shown in FIG. 1, a pair of enlarged diameter ring-shaped large diameter portions 36 are formed at both axial ends of the intermediate cylinder 30, and as shown in FIG. A radial outer peripheral surface 36A of the portion 36 is formed of the thin rubber layer 20 of the outer cylinder 16.
Is in close contact with. It should be noted that the corners of the outer peripheral surface 36A on the radial direction side of the large-diameter portion 36, the outer surface 36B, and the inner surface 36C are acute.

As shown in FIGS. 1 and 3, the axially intermediate portion of the intermediate cylinder 30 is reduced in diameter to form a small diameter portion 40. A recess 42 that is recessed toward the inner cylinder 22 is formed in a part of the small diameter portion 40.
And a notch 44 is formed on the side opposite to the recess 42 with the inner cylinder 22 interposed therebetween. Further, arcuate portions 46 and 48 are formed on both sides of the inner cylinder 22 between the recess 42 and the notch 44.

The recess 42 and the diaphragm 24 are opposed to each other, and the space between the recess 42 and the outer cylinder 16 is the sub liquid chamber 50.
It is said that.

As shown in FIG. 2, the elastic body 34 is formed with a through hole 52 axially penetrating to the concave portion 42 side of the inner cylinder 22. On the opposite side, a recess 54 is formed that is cut out toward the inner cylinder 22 side.

In the recess 54, a semicircular arc-shaped restricting passage forming member 56 is arranged as viewed in the axial direction. The limiting passage forming member 56 is made of an aluminum alloy die cast in this embodiment.

As shown in FIG. 2, the longitudinal section of the restricted passage forming member 56 is substantially hat-shaped. Corresponding to the restricted passage forming member 56, an arcuate step portion 59 is formed so as to project along the outer periphery of the large diameter portion 36 on the inner side surface 36C of the large diameter portion 36 of the intermediate cylinder 30. The radial outer peripheral surface of the step portion 59 is perpendicular to the inner side surface 36C of the large diameter portion 36. Further, a part of the elastic body 34 is thinly extended and fixed to the surface of the step portion 59.

The flange portion 58 of the restricted passage forming member 56 is sandwiched between the step portion 59 of the intermediate cylinder 30 and the thin rubber layer 20 of the outer cylinder 16. Both widthwise end portions of the flange portion 58 are in contact with the inner side surface 36C of the large diameter portion 36, whereby the restriction passage forming member 56 is prevented from moving in the axial direction.

As shown in FIG. 3, the arcuate portion 4 of the intermediate cylinder 30.
Protrusions 62 are formed on the concave portion 42 side of each of the reference numerals 6 and 48, and both longitudinal end portions of the limiting passage constituting member 56 abut on these protruding portions 62, so that the limiting passage constituting member 56 is rotated in the axial direction. Is blocked from moving. The bottom surface portion 56A of the restricted passage forming member 56 is in close contact with the arc portion 46 on one side in the longitudinal direction and is in close contact with the arc portion 48 on the other side in the longitudinal direction. Further, the outer surface of the side wall portion 56B of the restricted passage forming member 56 is in close contact with the seals 63 provided at both axial end portions of the circular arc portions 46 and 48.

A main liquid chamber 64 is formed between the restricted passage forming member 56 and the recess 54. Groove 6 of restricted passage forming member 56
Reference numeral 6 forms a limiting passage 68 between the outer cylinder 16 and the groove 66. One end of the groove 66 is closed by a closing wall 70 and the other end is connected to the sub liquid chamber 50. Further, an opening 72 is formed on the restriction passage forming member 56 on the side of the closing wall 70, and the restriction passage 68 is provided with the main liquid chamber 64 through the opening 72.
Is connected with.

The main liquid chamber 64, the sub liquid chamber 50 and the restriction passage 68 are filled with a liquid such as water or oil.

Next, the operation of the vibration isolator 10 of this embodiment will be described. This vibration isolator 10 is, for example, a mounting frame 12
Is connected to a vibration receiving portion such as a vehicle body of an automobile (not shown) and the inner cylinder 22 is connected to a vibration generating portion such as an engine (not shown), the vibration is generated by the inner cylinder 22, the elastic body 34 and the mounting frame 12
Is supported by a vibration receiving portion such as a vehicle body. At this time, the elastic body 34 is elastically deformed and the vibration is absorbed by the resistance based on the internal friction.
The vibration is absorbed by passing back and forth between 4 and the compound liquid chamber 50 to receive a passage resistance or resonate in a liquid column.

The vibration isolator 10 secures a predetermined dimension for the axial length A of the portion that seals the main liquid chamber 64 and the sub liquid chamber 50, that is, the large-diameter portion 36 of the intermediate cylinder 30, and is also vibration-proof. When the size of the device 10 (the length L in the axial direction and the outer shape) is the same, unlike the conventional vibration damping device using the intermediate cylinder formed by pressing the steel plate, the large diameter portion 36 Since the corners are acute, the axial dimension D of the sub liquid chamber 50 and the axial dimension C of the main liquid chamber 64 are made longer than those of the conventional vibration isolator. Along with this, the axial length of the diaphragm 24 is extended to increase the area of the diaphragm 24, so that the deformation amount of the diaphragm 24 with respect to the volume change of the sub liquid chamber 50 at the time of vibration is made smaller than that of the conventional vibration isolator. be able to. Therefore, a large stress does not act on the diaphragm 24 at the time of vibration input, and the diaphragm 24 does not contact the annular portion 14 even at the time of vibration with a large amplitude, and the durability of the diaphragm 24 is good.

Further, since the capacity of the sub liquid chamber 50 and the main liquid chamber 64 of the vibration isolator 10 is larger than that of the conventional vibration isolator, a large amount of liquid can be moved back and forth in the restriction passage 68, resulting in a large loss. The coefficient can be obtained. Also,
Since there is no unnecessary R portion at the corner of the large diameter portion 36, the step portion 59 which holds the flange portion 58 of the restricted passage constituting member 56 also has the dimension B.
Can secure a sufficient length.

Further, since the intermediate cylinder 30 is die-cast, there is no welded portion unlike the conventional intermediate cylinder having a welded structure of steel plates, and the small diameter portion 40 of the intermediate cylinder 30 is covered with an elastic body for sealing. There is no need. Further, since the intermediate cylinder 30 is made by die casting, it can be formed into a shape that could not be obtained by press molding, and the protrusion 62 can be easily formed on the small diameter portion 40. In addition to the role of the stopper for preventing the movement of the restricted passage forming member 56, the protrusion 62 also has a role of preventing the intermediate cylinder 30 from rotating in the vulcanizing mold during vulcanization of the elastic body 34. There is.

In this embodiment, the intermediate cylinder 30 and the restricted passage forming member 56 are made of aluminum alloy die cast, but the present invention is not limited to this, and the material of the intermediate cylinder 30 and the restricted passage forming member 56 is not limited to this. May be a metal or alloy other than aluminum alloy.

Further, the intermediate cylinder 30 and the restricted passage constituting member 5
6 may be a synthetic resin injection molded product.

Further, the intermediate cylinder 30 and the restricted passage forming member 5
Needless to say, 6 may be formed by a molding die, and may be formed by another type of molding method such as casting or lost wax. Even in these cases, it is possible to form an acute angle without forming the corner portion into the R shape.

[0037]

As described above, since the vibration isolator of the present invention has the above-mentioned structure, the capacity of the liquid chamber can be increased and the characteristics can be improved without increasing the size of the vibration isolator. Have an effect.

[Brief description of drawings]

FIG. 1 is an exploded perspective view of a vibration damping device according to the present invention.

FIG. 2 is a sectional view taken along line II-II of FIG. 3, showing a vibration damping device according to the present invention.

FIG. 3 shows an anti-vibration device according to the present invention, which is shown in FIG.
It is a II line disconnection figure.

FIG. 4 is a cross-sectional view taken along the axis of a conventional vibration damping device.

5 is a sectional view taken along line VV of FIG. 4, showing a vibration isolator according to a conventional example.

[Explanation of symbols]

 10 Vibration Isolator 16 Outer Cylinder 30 Intermediate Cylinder 50 Sub-Liquid Chamber 64 Main Liquid Chamber

Claims (1)

[Claims] 1. A plurality of liquid chambers connected by a restriction passage,
A liquid-filled type vibration damping device provided with an intermediate cylinder which is disposed in an outer cylinder and constitutes a part of a partition wall of the liquid chamber, and which is in close contact with an inner peripheral surface of the outer cylinder to prevent liquid from leaking out. And wherein the intermediate cylinder is made of a molding die in which a corner portion of an abutting surface of the intermediate cylinder that abuts an inner peripheral surface of the outer cylinder to prevent leakage of liquid is formed into an acute angle. Anti-vibration device.