JPH0599267A - Viscous buffer cylindrical bush - Google Patents

Abstract

PURPOSE:To enable full reduction especially against the vibration in the rotational direction in addition to the vibration in the direction perpendicular to the shaft. CONSTITUTION:A viscous buffer cylindrical bush is provided with an inner cylindrical body 2 and an outer cylindrical body 3 which are arranged coaxially, a liquid chamber 5 formed by a pair of rubber elastic body 4 which are interposed between the inner and the outer cylindrical bodies, a viscous liquid 6 enclosed in this liquid chamber, an inner plate 7 fitted to the inner cylindrical body in the liquid chamber, 'and an outer plate 8 fitted to the outer cylindrical body in the liquid chamber. The inner plate and the outer plate are arranged in an alternate manner by keeping them spaced from each other at the specified space so that the shearing resistance may be created between the opposite surfaces through the viscous liquid following the relative movement of the respective opposite surfaces.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a viscous cushioning cylindrical bush used in an automobile engine mount or the like.

[0002]

2. Description of the Related Art Conventionally, as a viscous cushioning cylindrical bush used in an automobile engine mount, one in which a viscous fluid is enclosed between an inner cylinder and an outer cylinder is known (for example, Japanese Unexamined Patent Application Publication No. Sho 6-66).
4-79443). This is provided with a plurality of donut-shaped elastic block members fitted inside the outer cylinder body, and an elliptical piston member whose center portion is fitted outside the inner cylinder body, and the axial side surface of the piston member is The block members adjacent to each other are slidably adhered to each other, and the small diameter portion of the piston member and the adjacent elastic block member separate the second and third liquid chambers from the first liquid chamber between the inner and outer cylinders. A liquid chamber is formed. A thin passage (orifice) that communicates the first liquid chamber and the second and third liquid chambers with each other is formed through the elastic block member, and is formed in a direction orthogonal to the axis, that is, in the radial direction. The damping effect is obtained by the resistance to the movement of the viscous fluid through the narrow passage against the vibration of the piston member in the direction of the small diameter portion.

[0003]

However, in the above-mentioned conventional viscous cushioning cylindrical bush, the damping effect of the orifice is that the piston member is connected in the direction perpendicular to the axis in the direction connecting the second and third liquid chambers. In reality, it is not possible to obtain a sufficient damping effect with respect to vibration in the axial direction or in the rotational direction around the axis, because it cannot be exhibited unless it is moved to.

The present invention has been made in view of the above circumstances, and an object thereof is to vibrate in a direction orthogonal to the axis (hereinafter, abbreviated as the axis perpendicular direction) and to rotate the axis. (EN) Provided is a viscous cushioning cylindrical bush capable of sufficiently damping even vibrations in the rotation direction (hereinafter, simply referred to as rotation direction).

[0005]

In order to achieve the above object, the invention according to claim 1 has an inner cylinder body and an outer cylinder body which are coaxially arranged apart from each other, and is interposed between the inner cylinder body and the outer cylinder body.
A pair of elastic bodies arranged apart from each other in the axial direction, a liquid chamber formed between the pair of elastic bodies, a viscous fluid enclosed in the liquid chamber, and a liquid chamber projecting toward the outer cylinder side in the liquid chamber. The inner plate thus attached to the inner cylinder body, and the outer plate attached to the outer cylinder body so as to project toward the inner cylinder body in the liquid chamber. Then, a plurality of the inner plates are arranged in the axial direction, the outer plate is arranged between adjacent inner plates, and the inner plate and the outer plate are moved in accordance with relative movement of the facing surfaces of the both. The viscous fluids are arranged alternately so as to be separated from each other by a predetermined distance such that shear resistance is generated between the facing surfaces.

The invention according to claim 2 is the above-mentioned claim 1.
In the invention described above, the inner plate and the outer plate are configured to be positionally fixed to the inner cylindrical body or the outer cylindrical body.

According to a third aspect of the present invention, in the above-mentioned first aspect of the invention, one or both of the inner plate and the outer plate are mounted so as to be axially movable relative to the inner cylindrical body or the outer cylindrical body. It is composed of.

According to a fourth aspect of the present invention, in the above-mentioned third aspect of the invention, a rotation regulating means for regulating the inner plate and the outer plate so as not to rotate relative to the inner cylindrical body or the outer cylindrical body may be provided. It is composed of.

According to a fifth aspect of the present invention, in the first aspect of the present invention, a biasing means for restoring the inner plate and the outer plate to a fixed axial position is provided.

According to a sixth aspect of the present invention, in the first aspect of the invention, one or both of the outer diameter of the inner plate and the inner diameter of the outer plate are set to be different from each other.

[0011]

With the above construction, in the invention according to claim 1,
When vibration in the rotation direction acts, the inner cylinder body and the outer cylinder body relatively rotate in directions opposite to each other with respect to the rotation direction, and the inner plate and the outer plate relatively shift in the rotation direction. Therefore, due to the frictional resistance with the viscous fluid, a shear shearing resistance in the direction opposite to the displacement direction of the two plates is generated between the facing surfaces of both plates. Vibration is dampened. Further, when the vibration in the direction perpendicular to the axis acts, the inner cylinder body and the outer cylinder body relatively move in a direction eccentric to each other, and like the case of the rotation direction, there is a gap between the opposed faces of the both plates. As a result, shear shear resistance is generated, which damps the vibration in the direction perpendicular to the axis. Further, when vibration in the axial direction occurs, the inner cylindrical body and the outer cylindrical body relatively move in the axial direction, and accordingly, the inner plate and the outer plate relatively move. The gap between the two changes and the viscous fluid is forcibly moved. The gap acts as an orifice, and the vibration in the axial direction is damped by the movement resistance when the viscous fluid moves. As described above, since the viscous shear resistance damps vibrations in the rotational direction and the axial direction, vibrations in a higher frequency range are damped as compared with the conventional damping due to movement resistance at the orifice in the bush. It

According to the invention described in claim 2,
In addition to the action of the invention described above, since the inner plate and the outer plate are fixed to the inner cylindrical body or the outer cylindrical body, both the plates are reliably kept at a predetermined interval, and the two plates face each other. Ensures that a predetermined disconnection resistance acts.

According to the third aspect of the present invention, in addition to the action according to the first aspect of the present invention, a sufficient damping action also occurs with respect to axial vibration. That is, when axial vibration occurs, relative movement occurs in the axial direction between the inner cylinder body and the outer cylinder body, and accordingly, the inner plate and the outer plate relatively move. At this time, since one or both of the inner plate and the outer plate are movable in the axial direction with respect to the inner cylinder or the outer cylinder, it is possible to move at least the predetermined distance in accordance with vibration, A sufficient damping action is obtained accordingly.

According to the invention described in claim 4, in addition to the effect according to the invention described in claim 3, even when the inner cylinder and the outer cylinder rotate relative to each other when vibration in the rotational direction acts, the inner plate And the outer plate are reliably regulated by the rotation restricting means so as not to rotate relative to the inner cylinder or the outer cylinder, and follow the inner cylinder or the outer cylinder so that the disconnection resistance is accompanied by the relative rotation. Works reliably.

According to the invention of claim 5, in addition to the operation of the invention of claim 1, even if the inner plate or the outer plate relatively moves in the axial direction due to the vibration in the axial direction, the inner plate or the outer plate is The biasing means ensures that the original position is restored, whereby the predetermined damping action is reliably maintained.

According to the invention of claim 6, in addition to the effect of the invention of claim 1, one or both of the outer diameter of the inner plate and the inner diameter of the outer plate are set to be different from each other. The opening cross-sectional areas of the fluid passages such as the gap between the outer peripheral edge of the plate and the outer peripheral surface of the outer cylinder and the gap between the inner peripheral edge of the outer plate and the outer peripheral surface of the inner cylinder are axially different from each other, which causes axial vibration. In this case, the movement resistance of the viscous fluid differs depending on the inner plate or the outer plate. Therefore, axial vibrations in a plurality of frequency regions corresponding to the movement resistance are damped. Along with this, when the outer diameters are different from each other, the areas of the inner plate and the outer plate facing each other are different from each other depending on the inner plate or the outer plate. The disconnection resistance of is generated. Therefore, vibrations in the rotational direction in a plurality of frequency regions corresponding to the plurality of shear resistances are damped.

[0017]

Embodiments of the present invention will be described below with reference to the drawings.

FIGS. 1 and 2 show a viscous cushioning bush 1 according to a first embodiment of the present invention. The bush 1 has an inner cylindrical body 2 serving as a shaft member and an axis X of the inner cylindrical body 2. An outer cylinder body 3 arranged coaxially, and a pair of rubber block bodies (elastic bodies) 4 interposed between the outer cylinder body 3 and the inner cylinder body 2.
A fluid 6 having a relatively high viscosity enclosed in a liquid chamber 5 formed between the pair of block bodies 4, and an inner plate 7 and an outer arranged coaxially with the axis X in the liquid chamber 5. The plate 8 is basically configured.

The block body 4 is separated by a predetermined distance in the axis X direction and externally fitted on the inner cylinder body 2 by vulcanization adhesion or the like, and the outer cylinder body 3 is fitted on the block body 4 to be hermetically sealed. A liquid chamber 5 which is a closed space is formed. Here, when the outer cylinder body 3 is fitted onto the block body 4, the outer cylinder tube 10 is embedded in the vicinity of the outer circumference of the block body 4, and the outer circumference and the end portion of the outer cylinder tube 10 are outside. A liquid-tight seal is formed by being compressed by the cylindrical body 3. Further, the inner plate 7 is fitted onto the inner tubular body 2 so that a plurality of inner plates 7 (in the example shown in FIG.
Sheets) are arranged at a predetermined distance from each other, and the outer plate 8 is made up of adjacent inner plates 7, 7.
It is arranged so as to be fitted inside the outer cylindrical body 3 at a position sandwiched therebetween. As a result, the inner plate 7 and the outer plate 8 are alternately arranged in the axis X direction with a predetermined distance therebetween.

The inner plate 7 and the outer plate 8 are formed in an annular shape from a material that produces a relatively high contact frictional resistance against the viscous fluid 6. The plurality of inner plates 7, 7, ... Have different outer diameters in a range smaller than the inner diameter of the outer cylindrical body 3,
The plurality of outer plates 8, 8, ... Are the inner cylindrical body 2
Have inner diameters different from each other in a range larger than the outer diameter. Therefore, the axial perpendicular gaps 511 to 514 between each inner plate 7 and the inner peripheral surface of the outer tubular body 3, and the axial perpendicular gaps 521 to each of the outer plate 8 and the outer peripheral surface of the inner tubular body 2. The passage of the viscous fluid 6 formed by 523 and the axial gaps 531 to 536 between the facing surfaces of the plates 7 and 8 has different passage cross-sectional areas along the passage, and Areas of overlapping portions (lap amounts, areas of annular portions shown by A in FIG. 1) facing each other between the facing surfaces are combined so as to be different from each other along the passage. In addition, the distance between the inner plate 7 and the outer plate 8 (the distance indicated by D in FIG. 1) is such that when the two adjacent plates move relative to each other in the plane direction,
The distance is initially set to such a distance that the shear-shear resistance force is generated between the opposed surfaces due to the contact friction resistance force with the viscous fluid 6. The spacing may be changed according to the viscous fluid 6 to be enclosed and the surface properties of the plates 7 and 8.

Next, to explain the operation and effect of the first embodiment, when vibration in the rotational direction around the axis X is input to the viscous buffer bush 1, the inner cylindrical body 2 and the outer cylindrical body 3 are connected. Relatively rotates about the axis X, and the inner plate 7 and the outer plate 8 relatively rotate in opposite directions. At that time, a shear shearing resistance force is generated between the opposing surfaces of the plates 7 and 8 through the viscous fluid 6. That is, a contact frictional resistance force is generated between the facing surfaces and the viscous fluid 6, and a viscous shear resistance force due to the viscosity of the viscous fluid 6 is generated. Then, the vibration in the rotation direction is absorbed and damped by the shearing resistance force.

Further, in this vibration damping in the rotational direction, since the lapping amounts of the plates 7 and 8 adjacent to each other on the facing surfaces are made different from each other in the axis X direction, the distance between the facing surfaces is increased. The shearing resistances generated at the different positions also differ from each other depending on the amount of lap. That is, a plurality of axial gaps 531 to 536 existing in the axial direction generate shear resistances of different magnitudes, and exhibit a plurality of damping characteristics corresponding to the shear resistances. For this reason, in the first embodiment, rotational direction vibrations in a plurality of frequency regions are damped. Further, in the first embodiment, the vibration absorption is performed by the disconnection resistance via the viscous fluid 6, so that the vibration absorption is performed by the movement resistance at the orifice like the conventional viscous buffer bush. In comparison, vibrations in the higher frequency range are damped.

When vibration in the direction perpendicular to the axis is input to the viscous cushioning bush 1, the inner cylindrical body 2 and the outer cylindrical body 3 are eccentric, and the inner plate 7 and the outer plate 8 move in the perpendicular direction (see FIG. 1). (For example, in the vertical direction). In this case, similarly to the case of the vibration in the rotation direction, a shear shearing resistance force is generated between the opposed surfaces of the plates 7 and 8 via the viscous fluid 6. For this reason, the vibration in the rotation direction is absorbed and damped by the shear shear resistance force. In this damping as well, vibration is absorbed by the shear resistance via the viscous fluid 6, so that there is a damping action for vibrations in a higher frequency range than when vibration is carried out by the moving resistance at the orifice. Same as for vibration.

In the viscous cushioning bush 1 of the first embodiment, the relative movement amount of the inner plate 7 and the outer plate 8 in the axial direction is determined by the axial gap 51.
1 to 514, 521 to 523 are limited to the smallest one (gap 511 in FIG. 1), and the smallest gap 511 has a relatively small gap in the axial direction (gap shown in FIG. 1B). Since it is set, the vibration absorption capacity in the perpendicular direction is also limited to a relatively small value corresponding to the interval in the perpendicular direction.

Further, when the vibration in the axis X direction is input to the viscous buffer bush 1, the inner cylinder 2 and the outer cylinder 3 are moved to the axis X.
The inner plate 7 and the outer plate 8 move relative to each other in the X-direction. With this relative movement, the viscous fluid 6 is forcibly moved within the liquid chamber 5, and during this movement, the axial gaps 511 to 514, 5 are formed.
Since 21 to 523 act as orifices, a movement resistance is generated in both plates 7 and 8. The movement resistance absorbs and attenuates the vibration in the X direction.

In this axial vibration damping, a plurality of axial gaps 511 to 514, 52 existing in the axial X direction are present.
Since 1 to 523 are formed so that their opening cross-sectional areas are different from each other, the movement resistance forces generated also differ from each other according to the above-mentioned opening cross-sectional areas. That is, a plurality of mutually different magnitudes of movement resistance force are generated due to the respective axial perpendicular gaps, and a plurality of damping characteristics corresponding to the plurality of movement resistance forces are exhibited. Therefore, in the first embodiment, axial vibrations in a plurality of frequency regions are damped. In the viscous cushioning bush 1 of the first embodiment, the inner plate 7 and the outer plate 8 are both fixed in position with respect to the inner cylindrical body 2 or the outer cylindrical body 3, so that they are relatively fixed in the axial X direction. Since the amount of movement is limited within the range of the initial setting interval of both plates 7 and 8, the vibration absorbing capacity in the axis X direction is also limited to that corresponding to the initial setting interval.

In this viscous buffer bush 1,
When a relatively large vibration or impact is applied, the rubber block body 4 absorbs the energy such as the impact in addition to the vibration absorption by the shear resistance via the viscous fluid 6.

As described above, in the first embodiment, it is possible to damp vibrations in the rotational direction, the axially perpendicular direction, and the axially perpendicular direction, and to isolate the vibrations. Particularly for vibration in the rotational direction, a sufficient damping effect can be exhibited by the shear resistance via the viscous fluid 6, and vibration in a higher frequency region can be effectively damped.
Moreover, since the amount of overlap between the inner plate 7 and the outer plate 8 is changed, it is possible to effectively damp vibrations in a plurality of different frequency regions. In addition, regarding axial vibration, the axial gaps 511 to 51 are also provided.
Since the opening cross-sectional areas of 4,521 to 523 are changed, vibrations in a plurality of different frequency regions can be similarly damped.

Incidentally, as the plurality of inner plates 7 and outer plates 8 in the first embodiment described above, FIG.
It is also possible to use the same shapes 7a and 8a as shown in FIG. In the viscous buffer bush 1a shown in FIG. 3, the liquid chamber 5
The axial clearances 511a to 514a, 521a to 52a
Since 3a and the axial gaps 531a to 536a have the same opening cross-sectional area, vibrations in a predetermined frequency region corresponding to the opening cross-sectional area are mainly damped.
Therefore, the viscous cushioning bush 1a is suitable for vibration damping for such one type of frequency region. Further, in this viscous cushioning bush 1a, by setting the axial distance of the axial gaps 511a to 514a and 521a to 523a larger than the minimum distance of the first embodiment, it is possible to sufficiently prevent the axial vibration. It is possible to obtain various damping effects.

4 and 5 show a viscous cushioning bush 1b according to a second embodiment of the present invention. In this viscous buffer bush 1b, a plurality of protrusions 21 extending in the axial X direction are formed on the outer peripheral surface of the inner cylindrical body 2b so as to project in the circumferential direction, and the protrusions 21 are formed on the inner peripheral edge of the inner plate 7b. A concave and convex engaging claw portion 71 that fits into the concave groove 22 between the adjacent ridges 21 and 21 is formed, and the engaging claw portion 71 fits into the convex line 21 and the concave groove 22. Thus, the inner plate 7b is attached so as to be relatively movable with respect to the inner cylindrical body 2b in the axis X direction and not to rotate relative to the axis X. Similarly, the outer cylindrical body 3b has a ridge 3 on its inner peripheral surface.
1 and the concave groove 32 are formed, and the outer plate 8
On the outer peripheral edge of b, an engaging claw portion 81 that fits into the convex line 31 and the concave groove 32 is formed, and the engaging claw portion 81 fits into the convex line 31 and the concave groove 32. Thus, the outer plate 8b is attached so as to be relatively movable in the axis X direction with respect to the outer cylindrical body 3b and not to rotate relative to the axis X. The protrusions 21 and 31, the concave grooves 22 and 32, and the claws 71 and 81 constitute the rotation restricting means 9. Further, a flange portion extending radially inward from the axially outer end is formed on the outer cylindrical tube 10a in the present embodiment, and the outer peripheral surface has the ridges 31 and the concave grooves 32 of the outer cylindrical body 3b. A gear-like concavo-convex to be fitted is formed by drawing, and by fitting the concavo-convex into the convex line 31 and the concave groove 32, the outer cylinder body 3b is sufficiently fitted to the block body 4. Has been Since the other constitution of the viscous cushioning bush 1b is similar to that of the first embodiment, the same members are designated by the same reference numerals and the description thereof is omitted.

In the case of the second embodiment, when vibration in the rotational direction is input to the viscous buffer bush 1b, the inner plate 7b is attached to the inner cylinder 2b and the outer plate 8b is attached.
Are attached to the outer cylindrical body 3b so as not to rotate relative to each other around the axis X, the plates 7b and 8b are displaced from each other in the above-described rotation direction, and their facing surfaces are displaced, as in the first embodiment. A shear shearing resistance force acts on the oil via the viscous fluid 6, and the vibration in the rotational direction can be damped by this shearing shear resistance force.

When vibration in the axis X direction is input, the inner plate 7b and the outer plate 8b relatively move in the axis X direction to forcibly move the viscous fluid 6, but the viscous buffer bush 1b. Then both plates 7 above
Since b and 8b can move in the direction of the axis X along the ridges 21 and 31, both plates 7b and 8b can move relative to each other within the range of the initial setting interval or more. For this reason, it is possible to perform greater absorption and damping with respect to the axial vibration as compared with the first embodiment. After the relative movement of the plates 7b and 8b, the viscous fluid 6 reversely pushes them in the opposite directions to restore them.

In the second embodiment, both the inner plate 7b and the outer plate 8b are configured to be movable in the axis X direction, but the invention is not limited to this. For example, only one of the inner plate and the outer plate can be moved. It may be movable. In this case, both plates can be moved relative to each other within the range of the distance between the fixed side plates.

FIG. 6 shows a viscous buffer bush 1c according to the third embodiment of the present invention. With this viscous buffer bush 1c,
Inner plate 7c is inner cylinder 2, outer plate 8
c is movably attached to the outer cylindrical body 3 in the direction of the axis X, and a rubber spacer (biasing means) 72 is attached to both of the plates 7c and 8c at the inner peripheral end of the inner plate 7c.
The rubber spacer (biasing means) 82 is the outer plate 8c.
Are fixed to the outer peripheral ends of the so as to project to both sides in the X direction.

The rubber spacers 72 come into contact with the rubber spacers 72 of the adjacent inner plates 7c, and also come into contact with the pair of block bodies 4 so as to hold the inner plates 7c at predetermined intervals in the axial X direction. The protrusion amount of is set. Similarly to the rubber spacer 72, the rubber spacer 82 has a projection amount in the axial X direction so as to hold the outer plate 8c at a predetermined position between the inner plates 7c. Further, in the rubber spacers 72, 82, the inner plate 7c is the inner cylinder 2 and the outer plate 8c is the outer cylinder 3 when the inner cylinder 2 and the outer cylinder 3 relatively rotate due to the contact friction resistance force. The inner cylindrical body 2 and the outer cylindrical body 3 are fitted so as to follow each of the above. Further, in the block body 4 in the present embodiment, the outer cylindrical tube 10 is embedded near the outer peripheral side thereof, and the inner cylindrical tube 10b is embedded near the inner peripheral side thereof,
The outer cylinder body 2 is press-fitted to the outer cylinder body 3 by the outer cylinder tube 10 and the inner cylinder tube 10b. Since the other constitution of the viscous cushioning bush 1c is similar to that of the first embodiment, the same members are designated by the same reference numerals and the description thereof is omitted.

In the case of the third embodiment, when vibration in the rotational direction is input to the viscous buffer bush 1c, the inner plate 7c follows the inner cylindrical body 2 and the outer plate 8c follows the outer cylindrical body 3, respectively. Since the two plates 7c and 8c are mounted in such a manner that the plates 7c and 8c are displaced from each other in the rotation direction as described in the first embodiment, a shear shear resistance force acts between their facing surfaces via the viscous fluid 6. However, the vibration in the rotation direction can be damped by the shearing resistance force.

When the vibration in the axis X direction is input, the inner plate 7c and the outer plate 8c relatively move in the axis X direction to forcibly move the viscous fluid 6, but the viscous buffer bush 1c is used. Then both plates 7 above
Since the c and 8c are movable in the direction of the axis X by the compression of the rubber spacers 72 and 82, the two plates 7c and 8c can be relatively moved within the range of the initial setting interval or more. Then, the compression restoring force of the rubber spacers 72 and 82 restores the plates 8c and 7c to their original positions. Therefore, the viscous cushioning bush 1c is capable of absorbing and damping a larger amount of axial vibration as compared with the first embodiment, and at the same time, the plates 7c and 8c.
It is possible to reliably restore c to the original initial setting interval as compared with the second embodiment. As a result, the predetermined damping effect on the axial vibration can always be reliably exhibited.

Although the rubber spacers 72 and 82 are used as the urging means in the third embodiment, the invention is not limited to this. For example, as shown in FIG. 7, the outer peripheral end portion of the inner plate 7d and the outer plate may be formed. Claws 73 and 83 that obliquely project are integrally formed at the inner peripheral end of 8d.
You may make it use 83 as a biasing means.

Further, instead of the rubber spacers 72 and 82 which are the urging means of the third embodiment, stopper portions 73 and 83 may be provided on both plates 7e and 8e as shown in FIG. That is, the stopper portions 73 and 83 protruding in the axis X direction are integrally formed at the inner peripheral end portion of the inner plate 7e and the inner peripheral end portion of the outer plate 8e, and by hitting the adjacent stopper portions 73 and 83, the inner cylinder Inner plate 7e for body 2, outer cylinder 3
The relative movement of each of the outer plates 8e with respect to is stopped. As a result, both plates 7e,
8e can move relative to the inner cylinder 2 or the outer cylinder 3 in the axial X direction by a predetermined amount, and can be prevented from moving further by the stopper portions 73 and 83. ..

The present invention is not limited to the above-mentioned first to third embodiments, but includes various other modifications. For example, the viscous cushioning bush may be constructed by combining the structure of the first embodiment with the rotation restricting means such as the convex strip of the second embodiment. Further, the viscous cushioning bush may be constructed by combining the constitution of the first embodiment with the biasing means of the third embodiment. Furthermore, the constitution of the first embodiment is combined with the rotation restricting means and the biasing means. A viscous buffer bush may be formed by using the above.

[0041]

As described above, according to the viscous cushioning cylindrical bush of the first aspect of the present invention, in addition to the vibration in the axial direction and the axial direction, the viscous fluid can be vibrated especially in the rotational direction. Sufficient damping can be performed by the shear resistance between the inner plate and the outer plate via the. Moreover, since the viscous shear resistance is used to damp the vibrations in the rotational direction and the axial direction, the vibration in a higher frequency region is damped as compared with the damping by the movement resistance at the orifice in the conventional bush. be able to.

According to the viscous cushioning bush of the second aspect of the invention, in addition to the effect of the first aspect of the invention, the inner plate and the outer plate are fixed to the inner cylinder or the outer cylinder. Therefore, it is possible to reliably maintain the distance between both plates to a predetermined amount, and it is possible to more reliably act a predetermined shearing resistance due to the displacement between the facing surfaces of both plates. In addition, according to this viscous cushioning bush, it is possible to provide a mount member that is suitable for damping vibration mainly in the axial direction and the rotational direction.

According to the viscous cushioning bush of the third aspect of the invention, in addition to the effect of the first aspect of the invention, it is possible to obtain a sufficient damping effect particularly for vibration in the axial direction.

According to the viscous cushioning bush of the fourth aspect of the invention, in addition to the effect of the third aspect of the invention, it is possible to reliably obtain a sufficient damping effect particularly for vibration in the axial direction and the rotational direction. You can

According to the viscous cushioning bush of the fifth aspect of the invention, in addition to the effect of the first aspect of the invention, it is possible to obtain a sufficient damping effect by vibrating in the axial direction, and by the biasing means. The inner plate and the like can be reliably restored to the initial setting state, and the predetermined damping action can be reliably maintained.

According to the viscous buffer bush of the sixth aspect of the invention, in addition to the effect of the first aspect of the invention, one or both of the outer diameter of the inner plate and the inner diameter of the outer plate are set to be different from each other. Therefore, it is possible to effectively damp rotational vibrations in a plurality of frequency regions and axial vibrations in a plurality of frequency regions.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing a viscous cushioning bush according to a first embodiment of the present invention.

FIG. 2 is a partially cutaway perspective view of the viscous cushioning bush of the first embodiment.

FIG. 3 is a vertical sectional view showing a modified example of the first embodiment.

FIG. 4 is a vertical cross-sectional view showing a viscous buffer bush according to a second embodiment.

5 is a cross-sectional view of an upper half portion taken along line AA of FIG. 4 and a lower half portion taken along line BB of FIG.

FIG. 6 is a vertical sectional view showing a viscous buffer bush according to a third embodiment.

FIG. 7 is a partial cross-sectional view showing another aspect of the third embodiment.

FIG. 8 is a vertical cross-sectional view showing another mode different from FIG. 7 in the third embodiment.

[Explanation of symbols]

 1, 1a, 1b, 1c, 1d, 1e Viscous buffer bush 2, 2a Inner cylinder 3, 3a Outer cylinder 4 Block body 5, 5a, 5b Liquid chamber 6 Viscous fluid 7, 7a, 7b, 7c, 7d, 7e Inner plate 8, 8a, 8b, 8c, 8d, 8e Outer plate 9 Rotation restricting means 10 Energizing means 31 Convex strip 32 Groove 71, 81 Engaging claw 72, 82 Rubber spacer 73, 83 Claw 74, 84 Stopper part

Claims (6)

[Claims] 1. An inner cylindrical body and an outer cylindrical body which are coaxially arranged apart from each other, a pair of elastic bodies which are interposed between the inner cylindrical body and the outer cylindrical body and which are arranged apart from each other in the axial direction, and the pair of elastic bodies. A liquid chamber formed between them, a viscous fluid enclosed in the liquid chamber, an inner plate attached to the inner cylinder so as to project to the outer cylinder side in the liquid chamber, and an inner cylinder side in the liquid chamber An outer plate attached to the outer cylindrical body so as to project to the inner plate, a plurality of the inner plates are arranged in the axial direction, the outer plates are arranged between the inner plates adjacent to each other, and the inner plate and the outer plate are arranged. The plates are alternately arranged at a predetermined interval such that a shearing resistance is generated between the facing surfaces via the viscous fluid due to the relative movement of the facing surfaces. Cylinder bush with viscous buffer. 2. The inner plate and the outer plate are positionally fixed to the inner cylindrical body or the outer cylindrical body.
The described viscous cushioning cylindrical bush. 3. The viscous cushioning cylindrical bush according to claim 1, wherein one or both of the inner plate and the outer plate are attached so as to be movable relative to the inner cylinder or the outer cylinder in the axial direction. 4. The viscous cushioning cylindrical bush according to claim 3, further comprising a rotation restricting means that restricts the inner plate and the outer plate from rotating relative to the inner cylinder or the outer cylinder. 5. The viscous cushioning cylindrical bush according to claim 1, further comprising a biasing means for restoring the inner plate and the outer plate to a constant axial position. 6. The viscous cushioning bush according to claim 1, wherein one or both of the outer diameter of the inner plate and the inner diameter of the outer plate are set to be different from each other.