JPH03181635A - Liquid sealed vibration isolator - Google Patents

Abstract

PURPOSE:To secure a liquid sealed vibration isolator as a whole inside a retaining opening with certainly so as to prevent any axial misalignment by reducing the diameter and deforming a retainer cylinder as a whole to inert it into the retaining opening, and securing the retaining cylinder inside the retaining opening by the diameter enlarging restoring force of elastic rubber layers. CONSTITUTION:Vibrationproof rubber 3 is interposed between an inner cylinder 1 and an outer cylinder 2 arranged coaxially with each other. A liquid chamber A for generating a vibration damping force is formed inside the vibrationproof rubber 3. Outside the outer cylinder 2, a retaining cylinder 4 constituted of a plurality of arcuate metal pieces 41, 42 divided at an interval in the circumferential direction is disposed. The arcuate pieces 41, 42 are joined at the outer periphery of the outer cylinder 2 by elastic rubber layers 51, 52, respectively. The retaining cylinder 4 is reduced in diameter and deformed as a whole until the arcuate pieces 41, 42 are brought into contact with each other, and the cylinder 4 is inserted into a retaining opening F1. Therefore, the arcuate pieces 41, 42 inserted into the retaining opening F1 are expanded in the circumferential direction with application of the restoring force of the elastic rubber layers 51, 52. The diameter of the retaining cylinder 4 is enlarged so that the cylinder 4 is pressed in contact with the inner circumference of the retaining opening F1, to be secured to the opening F1 with certainty.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a liquid-filled vibration isolator, and more particularly to a liquid-filled vibration isolator of a bush type in which a liquid chamber is formed in a vibration-proof rubber body disposed between an inner and outer cylinder. Regarding equipment.

[Prior art] Bush-type vibration isolators have been used for body mounts and suspension arm connections, in which a vibration isolating rubber body is placed between the inner and outer cylinders. A system has been proposed in which a liquid chamber is provided to efficiently damp especially low-frequency, large-amplitude vibrations (for example, Japanese Patent Laid-Open No. 63-3
12535).

On the other hand, bush-type vibration isolators have conventionally adopted a method in which an outer cylinder is fixedly installed within a holding opening of a vehicle frame.This outer cylinder is divided into halves with a gap in the circumferential direction.
A method of reducing the diameter of the outer cylinder, inserting the outer cylinder into the holding opening, and fixing the outer cylinder within the holding opening by the restoring force of the diameter expansion has been frequently used because of its high reliability.

[Problems to be Solved by the Invention] However, in the above-mentioned vibration isolating device in which a liquid chamber is formed inside the vibration isolating rubber body, it is impossible to make the outer cylinder into a half-split shape, so that removal from the holding opening is prevented. For this reason, a non-slip rubber layer is formed on the outer circumference of the outer cylinder (see the above publication). However, in this fixing method, the axial positioning is performed by the return deformation (buckling) of the rubber layer after it is press-fitted into the opening. In addition, the pull-out resistance depends on the surface roughness of the rubber layer, but this surface roughness varies widely depending on various conditions during molding, and the fixing reliability is lacking.

SUMMARY OF THE INVENTION The present invention has been made to solve this problem, and it is an object of the present invention to provide a bush-type liquid-filled vibration damping device that can be reliably positioned and fixed within a holding opening.

[Means for Solving the Problem] To explain the present invention in detail, the liquid-filled vibration isolator includes a vibration isolator between an inner cylinder 1 (FIGS. 1 and 2) and an outer cylinder 2 that are arranged concentrically. A rubber body 3 is provided, and a liquid chamber A that generates a vibration damping force is formed in the vibration isolating rubber body 3, and a plurality of chambers are provided outside the outer cylinder 2 and are divided with gaps in the circumferential direction. Metal arc piece 4
(2) A holding cylinder 4 consisting of 42 is provided, and each of the arcuate pieces 4 is
1.42 are respectively joined to the outer periphery of the outer cylinder 2 with elastic rubber 151.52.

[Function] In the liquid-filled vibration isolator having the above configuration, the holding cylinder 4 is deformed to reduce its diameter as a whole until the arcuate pieces 41 and 42 come into contact with each other, and then the holding cylinder 4 is inserted into the holding opening Fl.

Each of the arcuate pieces 41 and 42 inserted into the holding opening Fl expands in the circumferential direction under the restoring force of the elastic rubber layers 51 and 52, and the holding cylinder 4 expands in diameter and is brought into pressure contact with the inner periphery of the holding opening F1. , is securely fixed within the opening Fl.

[Example] In Figs. 1 and 2, the vibration isolator has a thick-walled inner cylinder 1 at the center, and a thin-walled outer cylinder 2 surrounding it.
A thick anti-vibration rubber body 3 is connected between the upper end of the inner cylinder (3) and the outer cylinder 2.

Ring bodies 61 and 62 are fitted to the inner periphery of the lower end of the outer cylinder 2 and the outer periphery of the flat end of the inner cylinder 2, respectively.
, 62, and the space below the vibration-proof rubber body 3 sealed by the rubber membrane 6 is defined as a liquid chamber A.

A disc body 7 is fixed to the outer periphery of the lower intermediate portion of the inner cylinder 1, and the outer periphery of the disc body 7 reaches near the ring body 62 and faces the inner periphery of the ring body 62 with a small gap. ing.

A holding cylinder 4 is disposed outside the outer cylinder 2, and the holding cylinder 4
is a pair of metal arc-shaped pieces 41 formed into an arc-shaped half-tube.
．． It is composed of 42. These arcuate pieces 41, 42 are arranged with a gap between their end faces in the circumferential direction (Fig. 2), and an elastic rubber layer 51, 52 of a predetermined thickness is joined between each inner periphery and the outer periphery of the outer cylinder 2. . The upper edges of each of the arcuate pieces 41, 42 are bent outward to form flanges 411, 421, and a portion of the rubber layer 51, 52 is extended onto the surface of these flanges 411, 421 to form a chevron-shaped cross section. Stopper part 53.
It is 54.

The liquid-filled vibration isolator having the above structure is installed by inserting and fixing the holding cylinder 4 into the holding opening Fl of the vehicle frame F, as shown in the figure. That is, the pair of arcuate pieces 4
When the holding cylinder 4 as a whole is deformed in diameter until L42 come into contact with each other and inserted into the holding opening Fl, the holding opening Fl
Each of the arcuate pieces 41 and 42 positioned inside expands in the circumferential direction under the restoring force of the elastic rubber layers 5 and 52, and the diameter of the holding cylinder 4 as a whole expands so that the outer periphery of each of the arcuate pieces 41 and 42 expands. The vibration isolator is in pressure contact with the inner periphery of the holding opening F1, and the vibration isolator is securely fixed within the opening F1.

A fixing bolt is inserted into the inner cylinder 1 of the vibration isolator fixedly installed in this way to connect and place the vehicle body. When vibration is input from the vehicle body, the inner cylinder 1 moves up and down in response, and the sealing fluid flows through the outer circumferential gap of the disc body 7 that moves up and down together with the inner cylinder 1, exerting a large vibration damping force. arise.

[Effect of the Invention 1] As described above, according to the liquid-filled vibration isolator of the present invention, the plurality of metal arc-shaped pieces constituting the holding cylinder are pressed against the inner periphery of the holding opening by the elastic force of the elastic rubber layer, and Since the inner periphery of the holding opening contacts the metal surfaces with a predetermined surface roughness, the entire device is securely fixed within the holding opening. Further, there is no possibility of axial positional displacement due to buckling as in the conventional case.

[Brief explanation of drawings]

Figure (3) is an overall sectional view of a liquid-filled vibration isolator according to an embodiment of the present invention installed on a vehicle frame, and the figure is a plan view of the same before installation. 1... Inner tube 2... Outer tube 3... Vibration-proof rubber body 41.42... Metal arc-shaped piece 51.52... Elastic rubber layer F... Vehicle frame Fl... Holding opening 2 Figure 2

Claims (1)

[Claims] A vibration isolating rubber body is provided between the inner cylinder and the outer cylinder which are arranged concentrically, and a liquid chamber that generates a vibration damping force is formed inside the vibration isolating rubber body, and a liquid chamber is provided outside the outer cylinder in the circumferential direction. A holding cylinder made of a plurality of metal arc-shaped pieces divided with gaps is provided,
Each of the arcuate pieces is joined to the outer periphery of the outer cylinder through an elastic rubber layer, and the holding cylinder as a whole is deformed in diameter and inserted into the holding opening. A liquid-filled vibration isolator characterized in that a holding cylinder is fixed within a holding opening.