JPS61189339A - Liquid-containing elastic bush - Google Patents

Abstract

PURPOSE:To reduce working man-hours, material cost, and weight by fitting, through caulking, an outer cylinder to an elastic member, to the end part of which an intermediate ring is attached, thereby ensuring liquid tightness for the liquid enclosed in liquid chambers. CONSTITUTION:An elastic member 3 installed between an inner cylinder 1 and an outer cylinder 2 is provided with a plurality of liquid chambers 5, which are separated from each other in the peripheral direction, at the middle part with respect to the axial direction of the member 3. These liquid chambers 5 are connected to each other by means of a throttle passage 9. Intermediate rings 4 and 4 are stuck through vulcanization to the end part in the axial direction of the elastic member 3, while the outer cylinder 2 is attached through caulking to these intermediate rings 4 and 4.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a liquid-filled elastic bushing that is used in automobiles, industrial machinery, and other devices and provides effective vibration isolation.

(Prior Art) Conventionally known liquid-filled elastic bushings that provide vibration damping mainly based on the flow resistance of an incompressible fluid sealed in a liquid chamber include, for example, German Patent No. 2.841.
There is one disclosed in the specification of No. 505.

This elastic bushing is made by fixing an intermediate cylinder with a window hole of dimensions corresponding to the contour of the liquid chamber to the outer periphery of an elastic member fixed to the inner cylinder and the outer cylinder, and a throttle passage formed on the outer periphery of the intermediate cylinder. This brings about communication between the liquid chambers.

(Problem to be solved by the invention) However, in such a liquid-filled elastic bushing, (
When assembling the outer cylinder, it is common to caulk and fix it to the outer periphery of the intermediate cylinder, so the crimping process deforms the throttle passage formed on the outer periphery of the intermediate cylinder, which is a rigid member, and prevents it from working as expected. Moreover, due to the caulking process, the incompressible liquid in the liquid chamber causes deformation of the elastic member in the circumferential and axial directions. acts to restrain their deformation, so a large initial stress acts locally on the interior of the elastic member and the joint surface between it and the intermediate cylinder, which reduces the durability of the elastic bushing and reduces vibration damping. There was a problem that performance was impaired.

Furthermore, since the intermediate cylinder is formed by forming a plurality of window holes in a cylinder member having approximately the same length as the elastic bushing, there is a problem that the processing man-hours and material costs increase, and the weight of the elastic bushing increases. Ta.

The present invention advantageously solves the problems of the prior art, and includes a throttle passage that is not affected at all or hardly by the caulking of the outer cylinder, and also eliminates the effect of locally large initial stress during the caulking. The purpose of the present invention is to provide a liquid-filled elastic bushing that effectively alleviates the problem and further reduces weight, processing steps, etc.

(Means for Solving the Problems) The liquid-filled elastic bushing of the present invention includes an elastic member provided between the inner and outer cylinders arranged concentrically, and a predetermined interval in the circumferential direction of the elastic member in the axial center of the elastic member. With multiple liquid chambers,
Furthermore, an intermediate ring is disposed between the elastic member and the outer cylinder at the axial end portion of the elastic member, and a low-rigidity throttle passage that brings the liquid chambers into communication with each other is arranged on the inner or outer surface of the elastic member or It is installed inside.

(Function) In this liquid-filled elastic bushing, by caulking the outer cylinder of the elastic member with the intermediate ring attached to the end portion, sufficient liquid-tightness against the fluid sealed in the liquid chamber is provided. By forming multiple window holes in the elastic member, processing steps, material costs, and weight can be reduced compared to the conventional technology in which the intermediate cylinder is constructed. The intermediate rings do not restrict the circumferential deformation of the elastic members that partition the liquid chambers, and the intermediate rings are spaced apart from each other against deformation of the elastic members in the axial direction. This separation of the intermediate ring makes it difficult for the pressure inside the liquid to rise, making it easier for liquid resonance to occur and increasing the vibration damping effect. In the part or its neighboring part,
Durability is improved because large initial stress does not act locally on the elastic members and their joint surfaces.

Furthermore, the diameter of the low-rigidity restricting passage provided on the inner or outer surface of the elastic member or inside the elastic member is expanded due to the increase in the internal pressure of the liquid during caulking of the outer cylinder. By determining the diameter of the throttle passage by taking into account the expansion of the passage diameter due to the increase in the internal pressure of the chamber, the initial vibration damping effect can be achieved under the passage length that meets the requirements.

(Example) The present invention will be explained below based on the drawings.

FIGS. 1(a) and 1(b) are cross-sectional views showing one embodiment of the present invention, in which 1 represents an inner cylinder, 2 represents an outer cylinder, and 3 represents an inner and outer cylinder made of steel, for example. The elastic member provided between the tubes 1 and 2 is shown.

Here, the elastic member 3 made of rubber, rubber-like elastic material, etc. is fixed to the inner cylinder 1 by vulcanization adhesive, bonding with an adhesive or adhesive, and 1, the outer cylinder 2 thereof is fixed. At the center part of the elastic member 3 in the axial direction, the outer cylinder 2 is caulked directly to the outer peripheral surface of the elastic member 3, and at the end part, the outer cylinder 2 is fixed to the elastic member 3 by applying, for example, vulcanized adhesive. This is achieved by caulking the outer cylinder 2 to the intermediate rings 4, 4 which have been formed. Therefore, the elastic member 3
The diameter of the part of the outer cylinder 2 where the outer cylinder 2 is directly caulked is slightly larger than the outer diameter of the intermediate ring 4.4 so as not to create a gap between the elastic member 3 and the outer cylinder 2. It is necessary to Note that the caulking process here is preferably performed by drawing in a hexagonal direction in a liquid in order to prevent air from flowing in and to prevent the O-ring from getting caught.

Further, here, the elastic member 3 is provided with two diametrically opposed depressions 3a at its central portion in the axial direction, and the space formed by the depressions 3a, the intermediate ringay, and the outer cylinder 2 is inserted into the elastic member 3. By enclosing an incompressible liquid, two opposing liquid chambers 5 are formed, and each of these liquid chambers 5 includes:
A stopper 6 protruding from the inner cylinder side or the outer cylinder side is provided. This stopper 6, which is not an essential component in the present invention and protrudes from the inner cylinder side in the illustrated example, is formed by, for example, fitting and fixing a bossed rigid member 7 to the inner cylinder 1, and attaching the elastic member 3 to the surface thereof. The stopper 8 can be constructed by covering the elastic material 8 of the same quality, and when the amount of relative displacement between the inner and outer cylinders 1.2 becomes excessive, the stopper 8 prevents the relative displacement from occurring under the buffering action of the elastic material 8. It acts to restrain.

Furthermore, in this example, in the part of the elastic member 3 where the outer cylinder 2 is caulked directly, the elastic member 3 and the outer cylinder 2 are
A low-rigidity throttle passage 9 is provided between the liquid chamber 5.5 and the liquid chamber 5.5. This throttle passage 9 is, for example, shown in FIG.
), a groove 3b is provided on the outer periphery of the elastic member 3 and has a curved cross-sectional shape such as an arc shape or a U-shape;
In addition to the groove facing portion of the outer cylinder 2 which is caulked onto the elastic member to close the opening of the groove 3b, the inner groove 3b provided as shown in FIG. fart,
It can also be constructed by fitting pipes 10 of low rigidity tightly together as shown in FIG. 2(b).

Here, if the concentration of stress on the peripheral surface of the throttle passage 9 is not a problem, the cross-sectional shape of the throttle passage 9 may be shaped into a corner such as a triangle or a square, regardless of whether or not a low-rigidity pipe is fitted. Alternatively, the cross-sectional shape of the restrictor passage 9 may be changed to a radially inner position of the elastic member 3, as long as a sufficient restrictor passage length is ensured to provide the desired vibration damping. It can be provided in a curved or angular shape, in a straight line or in red and white.

According to such a liquid-filled elastic bushing, the intermediate ring 4.4, which can be made of steel, for example, provides sufficient liquid tightness in the axial direction of the bushing by caulking the outer cylinder 2 thereto, and also provides elastic The central part of the member 3 provides liquid tightness in the circumferential direction of the bushing by caulking the outer cylinder 2 thereto. Therefore, the flow of the incompressible fluid in the bunsch takes place only through the restriction passage 9, and the restriction passage 9, whose length is appropriately selected, causes various energy losses to the liquid passing therethrough. Therefore, vibrations transmitted to the inner cylinder or outer cylinder are damped as expected by the energy loss.

Note that since a simple ring is sufficient as the intermediate ring 4.4 here, the number of processing steps, material cost, and weight are reduced compared to the prior art. Moreover, these intermediate rings 4, which are fixed only to both ends of the elastic member 3,
4, when caulking the outer cylinder 2, the deformation of the elastic member 3 in the circumferential direction and the axial direction is not restrained so much, so the increase in internal pressure in the liquid chamber is small, liquid resonance is more likely to occur, and the vibration damping effect is increased. Further, a large initial stress does not act on the joint portions of the elastic member 3 to the intermediate rings 4, 4 or the vicinity thereof, and therefore the durability and vibration damping characteristics of the elastic bushing are improved.

Furthermore, by determining the initial dimensions of the low-rigidity restricting passage 9 in consideration of the increase in liquid chamber pressure, the low-rigidity restricting passage 9 can be prevented from being undesirably deformed due to caulking of the outer cylinder 2. The vibration damping function can be achieved as expected.

The present invention has been described above based on the illustrated example, but the illustrated example has one throttle passage, but the throttle passage may be made into two or more, and the throttle passage may be made red or white in at least one of the axial direction and the radial direction of the elastic bushing. It is also possible to have three or more liquid chambers.

(Effects of the Invention) Therefore, according to the present invention, in particular, an intermediate ring is provided at both ends of the elastic member, and a low-rigidity throttle passage is provided in the center portion of the elastic member to allow a plurality of liquid chambers to communicate with each other. This reduces the processing time, material cost, and weight of the intermediate ring itself and the elastic bushing, and also reduces the damping effect due to the increase in hydraulic pressure when assembling the outer cylinder, deforms the throttle passage, and reduces local This means that the generation of a large initial stress can be sufficiently and effectively prevented.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an embodiment of the present invention, and FIG. 2 is a sectional view showing an example of the configuration of a throttle passage. 1... Inner cylinder 2... Outer cylinder 3... Elastic member 3b... Groove 4... Intermediate ring 5
...liquid chamber 9...throttle passage 10...pipe patent applicant Brideston Co., Ltd. Figure 1 (a) (1)) (3) (b)

Claims (1)

[Claims] 1. An inner cylinder and an outer cylinder arranged concentrically, an elastic member provided between these inner and outer cylinders, and a plurality of liquid chambers provided at predetermined intervals in the circumferential direction at the axial center of the elastic member. A liquid-filled elastic bushing comprising: an intermediate ring provided between the elastic member and the outer cylinder at an axial end portion of the elastic member; and a low-rigidity throttle passage that brings the liquid chambers into communication with each other.