JP2001241483A - Hydraulic shock absorber - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hydraulic shock absorber capable of providing in a space of narrow width without deteriorating damping performance of the hydraulic shock absorber. SOLUTION: In an intermediate part of an outer cylinder 2 of this hydraulic shock absorber 1, a protrusion part 9 having a width W of external diameter R or less of the outer cylinder 2 is formed to protrude toward the upward. In the inside of this protrusion part 9, a reservoir 8 is constituted by providing a bag unit 10 made of polyester to seal gas in the inside. By this constitution, even in the case that a diameter of an inner cylinder 4 approaches to a diameter of the outer cylinder 2 by inevitably making it small, a capacity of the reservoir can be efficiently ensured, damping performance can be ensured.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a double cylinder type hydraulic shock absorber.

[0002]

2. Description of the Related Art Conventionally, a technique for providing a hydraulic shock absorber in the wall of a building to attenuate the vibration of the building is disclosed in JP-A-49-114415.

FIG. 5 shows a case where such a technique is used as a vibration damping device for a general wooden house.

[0004] Pillars 21, 22 are erected on the foundation 20,
A beam 23 is provided at the upper end of the column. The lower panel 24 that transmits the horizontal movement of the foundation 20 to the foundation 20, and the upper panel 2 that transmits the horizontal movement of the beam 23 to the beam 23.
5 is fixed.

[0005] A hydraulic shock absorber 28 is mounted between the lower panel 24 and the upper panel 25 by mounting plates 26 and 27.

When an earthquake occurs, the basics 2
0 and the beam 23 move relative to each other in the horizontal direction, and the lower panel 24
And the upper panel 25 also move in the horizontal direction by substantially the same amount.
At this time, since the outer cylinder 29 side is attached to the lower panel 24 and the piston rod 30 side is attached to the upper panel 25, the piston rod 30 expands and contracts, and a damping force generating mechanism in a hydraulic shock absorber (not shown) Generates damping force.
Damping by this damping force, suppressing the building from resonating,
Prevent building collapse.

[0007]

In such a hydraulic shock absorber used for a vibration damping device, in order to generate a stable damping force for a minute stroke, the diameter of a piston in the hydraulic shock absorber is required. Needs to be as large as possible to increase the amount of oil flowing when the piston moves.

[0008] However, when the diameter of the piston is increased, the diameter of the hydraulic shock absorber increases, and there is a problem that the hydraulic shock absorber cannot be provided in a narrow wall.

An object of the present invention is to provide a hydraulic shock absorber which can be provided in a narrow space without deteriorating the damping performance.

[0010]

Means for Solving the Problems To solve the above problems, the present invention has the following features.

The present invention provides a multi-cylinder hydraulic shock absorber in which a reservoir is provided between an outer cylinder and an inner cylinder, and a piston fixed to a piston rod is slidably provided in the inner cylinder. On the side of the outer cylinder, a protrusion having a radial width less than or equal to the outer diameter of the outer cylinder is formed by plastic deformation, and a bag body having a gas therein is provided in the protrusion. I do.

Therefore, according to the present invention, the piston diameter can be made as large as possible, and the radial width of the hydraulic shock absorber can be minimized.

[0013]

FIG. 1 is a side view of a hydraulic shock absorber 1 according to an embodiment of the present invention, FIG. 2 is a bottom view, FIG. 3 is an axial sectional view, and FIG. An AA end view is shown and described.

The hydraulic shock absorber 1 is usually installed so that the axial direction is horizontal. From one end of the cylindrical outer cylinder 2, the piston rod 3 projects through the rod guide 11 and the seal 12 so as to be able to expand and contract.

One end of the piston rod 3 has an inner cylinder 4
The piston 5 is provided with a damping force generating mechanism 6 which includes a disk valve and an orifice and generates a damping force when the piston rod 3 expands and contracts.

At the other end of the outer cylinder 2 is provided a bottom valve 7 made up of a disk valve or an orifice, and a reservoir 8 formed between the outer cylinder 2 and the inner cylinder 4 via the bottom valve 7. And the inside of the inner cylinder 4 are communicated. And
When the piston rod 3 is extended, the inner cylinder 4
When the piston rod 3 is shortened, the oil is supplied from the inner cylinder 4 to the reservoir 8 with almost no damping force.
The damping force is generated to cause the oil liquid to flow out.

A projection 9 having a width W equal to or smaller than the outer diameter R of the outer cylinder 2 is formed at an intermediate portion of the outer cylinder 2 so as to protrude upward.

Inside the projection 9, there is provided a cylindrical bag body 10 made of polyester and filled with gas.

Here, the upper portion 9A of the projection 9 has a circular shape such that the inside has substantially the same diameter as the outer diameter of the bag 10,
The bag body 10 is fitted with the upper part 9A of the projection 9.

With this bag 10, compensation for intrusion of the piston rod 3, compensation for temperature, and compensation for oil leakage can be performed.

The protruding portion 9 plastically deforms the outer cylinder by press working at an intermediate portion of the cylindrical tube, or by providing a mold outside the cylindrical tube and applying fluid pressure to the inside to perform press working by fluid pressure. It is formed by this. And the upper end of the outer cylinder 2 is circular.

In the hydraulic shock absorber of the above embodiment,
Even if the diameter of the inner cylinder 4 is set to a value close to the diameter of the outer cylinder 2, a sufficient reservoir volume can be secured inside the projection 9 without increasing the overall width W. Therefore, the damping performance is not sacrificed even when the mounting space is restricted, such as when the mounting space is provided in the wall space as shown in FIG.

Further, the bag body 10 can be formed in a cylindrical shape,
Since the bag body 10 is easy to manufacture and the width W of the projection 9 is equal to or smaller than the outer diameter R of the outer cylinder 2, when the bag body 10 is formed into a cylindrical shape, the outer diameter of the bag body is equal to or smaller than the width W, that is, Since the diameter is equal to or less than the inner diameter of the outer cylinder 2, it can be easily inserted into the outer cylinder 2.

[0024]

As described above, according to the present invention, a protrusion having a width in the radial direction smaller than the outer diameter of the outer cylinder is formed on the side of the outer cylinder by plastic deformation. Since the bag body containing gas is provided inside, the diameter of the inner cylinder can be increased without increasing the width of the hydraulic shock absorber, and sufficient damping performance is obtained even in a narrow mounting environment. be able to.

[Brief description of the drawings]

FIG. 1 is a side view of a hydraulic shock absorber showing an embodiment according to the present invention.

FIG. 2 is a view of the hydraulic shock absorber of FIG. 1 as viewed from a bottom direction.

FIG. 3 is an axial sectional view of the hydraulic shock absorber of FIG. 1;

FIG. 4 is an AA end view of the hydraulic shock absorber of FIG. 1;

FIG. 5 is a view showing a state in which a conventional hydraulic shock absorber of the present invention is provided in a wall surface as a vibration damping device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Hydraulic shock absorber 2 Outer cylinder 3 Piston rod 4 Inner cylinder 8 Reservoir 9 Protrusion 10 Bag

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI theme coat ゛ (Reference) F16F 9/32 Z (72) Inventor Yuugi Takagi 1116 Koizono, Ayase-shi, Kanagawa Tokiko Co., Ltd. 72) Inventor Ryo Matsuno 1116 Kozono, Ayase-shi, Kanagawa F-term in Sagami Plant of Tokiko Corporation 2E001 DG01 DH31 FA03 FA71 GA01 KA03 LA11 3J048 AA06 BE03 DA01 EA38 3J069 AA52 AA54 CC10 EE73

Claims (1)

[Claims] 1. A multi-cylinder hydraulic shock absorber in which a reservoir is provided between an outer cylinder and an inner cylinder, and a piston fixed to a piston rod is slidably provided in the inner cylinder. Hydraulic pressure characterized by forming a protrusion having a width in the radial direction smaller than the outer diameter of the outer cylinder by plastic deformation on a side portion of the cylinder, and providing a bag body having gas inside the protrusion. Shock absorber.