JP2000018202A - Pressure pulsation absorbing foamed body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pulsation preventing structure for reducing pulsation of a pressurized fluid flowing in a pressure piping capable of absorbing a large quantity of pulsation surge of the fluid in the pressure piping. SOLUTION: This pressure pulsation absorbing foamed body absorbs pulsation, which is formed by wrapping a formed body of elastic material 1a in an elastic film 1b. Projections and recessions are formed on the surface of the formed body, which are immersed in pressurized fluid flowing. Accordingly, a flexible change in capacity to the inside of the formed body is available to obtain a high pulsation absorbing effect.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pulsation prevention device used for reducing pulsation of a pressure fluid in a pressure line system, and more particularly, to a pressure and flow pulsation of a pressure fluid flowing in a pipe. The present invention relates to a pulsation absorbing structure that efficiently absorbs.

[0002]

2. Description of the Related Art Conventionally, as means for suppressing the pulsation of a pressure fluid, a bladder or diaphragm made of synthetic rubber is used in an accumulator to which a bladder or a diaphragm is attached, and in a piston type accumulator type, the piston and a spring are used. In a bellows-type accumulator, the bellows is used to suppress the pressure by changing the volume or spring of the enclosed gas in response to pressure fluctuations in the fluid (absorption).
are doing. Among these, as an in-line accumulator, there is an accumulator having a configuration as shown in FIG. 4 when described with reference to the drawings.

In this accumulator, end covers (3a) are respectively attached to outer cylinder portions (3) each formed in a substantially cylindrical shape, and a swelling tube made of synthetic rubber connected to the end covers (3a) at both ends. A bladder (4) having a shape is arranged, the inside of the bladder (4) is used as a pressure fluid flow path, and a gas (5) is sealed between the outer cylinder (3) and the bladder (4). A structure in which an inner tube (6) in which a number of holes are cut in order to suppress excessive deformation of the bladder (4) is disposed on the inner peripheral side of (4) is a generally used configuration. is there.

[0004]

[SUMMARY OF THE INVENTION However, accumulator of such an inline-type structure can be cited as a complex and expensive biggest drawback is the point is, also, use applications limited, N ₂ pressure gas It has various drawbacks that cannot be generalized, such as accompanying complicated maintenance. In order to solve such a drawback, a simple structure (not shown) for reducing the pulsation of the fluid pressure by mounting a foamed rubber body in the pressure fluid flow path has been considered. When pulsation is repeated, the air inside the cells of the foamed rubber body leaks into the liquid, or the permeation of the liquid into the foamed rubber body through the rubber penetrates the fatal defect that the pulsation prevention effect is reduced early. Therefore, this has not yet become popular.

In view of the drawbacks, the present invention has invented a simple and wide-ranging pulsation absorbing material based on an unconventional idea, and is capable of generating a large amount of pulsating surge of fluid in a pressure line. It is intended to provide a pressure pulsation absorber for absorbing.

[0006]

The present invention is constituted by the following constitution. The present invention, as shown in FIG.
1. A pressure pulsation absorbing foam (1) for effectively absorbing pulsations arranged in a high voltage circuit, as shown in FIG. 1, foaming an elastic body such as synthetic rubber or synthetic resin into an appropriate foam. To form a foam (1a), and from the outside of the foam (1a), an elastic thin film (1a) having low permeability.
b) wrapping to form a pressure pulsation absorbing foam (1). At this time, the surface is shaped into an uneven shape (12b) such as a wrinkle, a wave, or a fold, and the pressure pulsation absorbing foam (1) is immersed in the pressure fluid in the pressure pipe (2) system.

Further, as shown in FIG. 2, a pressure pulsation absorbing foam (1) is formed by foaming an elastic body made of synthetic rubber, synthetic resin or the like to form a foam (1a) having a constant thickness. From the outside, a plate-shaped pressure pulsation absorbing foam (1) is wrapped with an elastic thin film (1b) having low permeability to form a plate-like pressure pulsation absorbing foam (1). As shown in the drawing, it is characterized by being immersed in the pressure fluid in the pressure line (2) system.

[0008]

As described above, the present invention relates to a pressure pulsation absorbing foam (1) in which a foam (1a) having closed cells is wrapped in a thin film (1b) having low permeability in a pressure line (2) system. ) Is arranged to allow the pressurized fluid to flow therethrough. In the mounting operation, the surface is formed into an uneven shape (12b) or the plate-like molded product is screwed into a spiral shape (13b) to reduce the surface area. When it is dramatically expanded and immersed in a hydraulic circuit, the pulsation and surge pressure of the pressure fluid generated by various control devices are extremely effectively suppressed.

The closed cells of the pressure pulsation absorbing foam (1) each have a gas inside and have a balloon shape with high elasticity. And, since this is wrapped in a thin film (1b) having low permeability of liquid, the danger of liquid permeating into the inside as well as the outer surface of the closed cell is eliminated, and each closed cell is formed by the fluid pressure. Each time the volume is changed, the pressure change is absorbed.

The absorption function is further enhanced by the uneven shape (12b) formed on the surface, and each of the unevennesses, particularly the concave portion, has a receiving plate structure to completely receive the pressure pulsation, and does not allow it to escape. Absorb all. Naturally, the large surface area formed by the concavo-convex shape (12b) or the spiral shape (13b) greatly contributes to the pulsation absorbing action. Particularly, in the spiral shape (13b), a large area of both entrained surfaces is exposed. Therefore, the pulsation can be alleviated, so that an efficient pulsation absorbing effect can be expected. Regarding this absorbing effect, the foam (1a) of the pressure pulsation absorbing foam (1) has the irregular shape (12b).
As a result, the gas is placed in a state close to a state in which the gas is dispersed in the liquid, and the individual bubble portions flexibly receive the changed bubble volume near the contacting surface. Then, a fluid without pulsation, pressure change, and the like can be pumped to another device.

[0011]

Embodiments of the present invention will be described below in detail with reference to the drawings. In FIG. 3, a recess (2) is provided on the side of the pressure line (2).
a) is provided with the pressure pulsation absorbing foam (1) of the present invention mounted in the concave portion (2a). Here, the pressure pulsation absorbing foam having a spiral shape (13b) against large pulsation or strong impact is provided. The large outer surface structure of (1) shows a sufficient allowance, and can exhibit an effective absorption action. When the pressure pulsation absorbing foam (1) having the spiral shape (13b) shown here is disposed so that the direction of the winding axis is perpendicular to the flow of the fluid, a wide surface thereof may directly contact the pressure pulsation. It can provide quick and accurate absorption. In addition, it is possible to use the above-mentioned uneven shape (12b) and spiral shape (13b) together, and in this structure, it is possible to prevent surface contact due to wrapping, so that absorption efficiency can be further increased.

The thin film (1b) is made of a film-like elastic material such as synthetic rubber having low permeability to liquid or gas, or an elastic material having low permeability to liquid or gas. (For example, a fluororesin coating or the like). On the other hand, the uneven shape can be freely shaped such as a straight or bent strip corresponding to the flow from the shape in which the concave and the convex are alternately provided, and can cope with the required performance in any way. Things.

[0013]

According to the above configuration, the following excellent effects can be obtained. In the pressure pulsation absorbing foam (1) of the present invention, the uneven shape (12b) or the spiral shape (1) is used.
3b) secures a large surface area and achieves an excellent pulsation absorbing action which cannot be considered conventionally. In addition, closed cells without liquid permeation can be flexibly changed in volume to the inside of the foam due to the uneven shape (12b) penetrating into the inside, and it is possible to absorb pulsations in a wide frequency range from high frequency to low frequency. Become. Further, since the elastic body is formed by covering the foam with a thin film, it can be freely bent and stretched, so that a mounting shape with a small flow resistance of the fluid is possible, and the pressure loss is extremely small.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention.

FIG. 2 is a perspective view showing another embodiment of the present invention.

FIG. 3 is a sectional view showing a mounted state of the embodiment shown in FIG. 2;

FIG. 4 is a sectional view showing a conventional structure not using the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Pressure pulsation absorption foam 1a Foam 1b Thin film 12b Concavo-convex shape 13b Spiral shape 2 Pressure pipeline 2a Depression 3 Outer cylinder 3a End cover 4 Bladder 5 Gas 6 Inner tube

Claims (2)

[Claims] 1. A pressure pulsation absorbing foam disposed in a high-pressure circuit for absorbing pulsation, the foam being formed by foaming an elastic body and having a low permeability from the outside thereof. When wrapped in a thin film to form a pressure pulsation absorbing foam, its outer surface is wrinkled,
A pressure pulsation absorbing foam characterized by being formed into a corrugated or fold-like uneven shape and immersed in a fluid in a pressure pipe system. 2. A pressure pulsation absorbing foam disposed in a high-pressure circuit for absorbing pulsation, the foam being formed by foaming an elastic body, and having a low permeability from the outside thereof. A pressure pulsation absorbing foam characterized by forming a plate-shaped pressure pulsation absorbing foam by wrapping it in a thin film, screwing it into a spiral shape, and immersing it in a fluid in a pressure pipeline system.