JPH04321801A - Bladder for accumulator - Google Patents

Abstract

PURPOSE:To suppress stress concentration and extend the life of a bladder. CONSTITUTION:There are provided a fixing part (11C) which is fixed to an inner circumferential surface of a shell by means of a holder diaphragm part (11B) which is continuous relative to the fixing part (11C) and extended along the inner circumferential surface of the shell in an unloaded condition when fitted to the shell inner circumferential surface, and a bellows part (11A) which is continuous relative to the diaphragm part (11B) and reversed toward the fixing part (11C) side. This constitution allows the stress concentration to be suppressed and the life to be extended, and enables manufacturing with elastic synthetic resin material which is excellent in gas shielding property.

Description

[Detailed description of the invention]

0001

[Purpose of the invention]

0002

[Field of Industrial Application] The present invention relates to a bladder for an accumulator, and in particular, to a bladder for an accumulator, a fixed part fixed to the inner circumferential surface of a shell by a holder, and a bladder connected to the fixed part and attached to the inner circumferential surface of the shell. This invention relates to an accumulator bladder comprising a diaphragm part that extends along the inner peripheral surface of the shell in an unloaded state, and a bellows part that is continuous with the diaphragm part and is inverted toward the fixed part side. .

0003

2. Description of the Related Art Conventionally, this type of accumulator bladder has a central portion 31A and a peripheral portion 31B connected to each other via a curved inverted portion 31C, such as an accumulator bladder 30 shown in FIG. 40 is arranged on the inner peripheral surface of the shell 41 by a mounting member 42, and the internal space of the shell 41 is connected to the gas chamber 41A.
The central portion 31A is made to protrude toward the end face of the peripheral portion 31B under no load, and as the liquid pressure in the liquid chamber 41B decreases, the central portion 31A is divided into a liquid chamber 41B and a liquid chamber 41B.
A moves toward the liquid chamber 41B (also referred to as the "discharge direction"), and as the liquid pressure in the liquid chamber 41B increases, the central portion 31A moves toward the gas chamber 41A (also referred to as the "suction direction"). It was proposed to move towards the

0004

[Problems to be Solved] However, in the conventional accumulator bladder 30, (i) the central portion 31A and the peripheral portion 31B are connected to each other via the curved inverted portion 31C;
There is a drawback that stress (and therefore strain) tends to concentrate at the connecting portion with the peripheral edge portion 31B, and (ii) since the elastic material layer is made of a rubber material such as natural rubber, it cannot cope with an increase in the operating temperature. First, there was a drawback that sufficient gas shielding properties could not be ensured when downsizing or extending the lifespan.

[0005] Therefore, in order to eliminate these drawbacks, the present invention provides a fixing part that is fixed to the inner circumferential surface of the shell by a holder, and a fixing part that is continuous with the fixing part and attached to the inner circumferential surface of the shell. It is an object of the present invention to provide an accumulator bladder comprising a diaphragm part that extends along the inner peripheral surface of the shell in an unloaded state and a bellows part that is continuous with the diaphragm part and is inverted toward the fixed part side. It is something to do.

[0006]

[Structure of the invention]

[0007]

[Means for Solving the Problems] The means for solving the problems provided by the present invention is as follows: In an accumulator bladder whose peripheral edge is in contact with the inner circumferential surface of the shell of the accumulator and is fixed by a holder, (a) the shell A fixing part (11C) fixed to the inner peripheral surface by a holder, and (b
) a diaphragm part (11B) that is continuous with the fixed part (11C) and extends along the inner peripheral surface of the shell in an unloaded state when attached to the inner peripheral surface of the shell;
(c) A bellows part (11A) which is continuous with the diaphragm part (11B) and is inverted toward the fixed part (11C).

[0008]

[Function] As clearly stated in the above-mentioned [Means for solving problems] section, the bladder for an accumulator according to the present invention is for use in an accumulator, in which the peripheral edge is in contact with the inner peripheral surface of the shell of the accumulator and is fixed by a holder. A bladder, in particular, has a fixed part that is fixed to the inner circumferential surface of the shell by a holder, and a fixed part that is continuous to the fixed part and that when attached to the inner circumferential surface of the shell, is attached to the inner circumferential surface of the shell in a no-load state. Since it includes a diaphragm part that extends along the diaphragm part, and a bellows part that is continuous with the diaphragm part and is reversed toward the fixed part, (i) the connecting part between the fixed part and the diaphragm part or the diaphragm part; and functions to suppress stress concentration on the connecting part of the bellows part, thereby (ii
) acts to extend lifespan, and (iii)
This function allows it to be made using an elastic plastic material that has superior gas shielding properties compared to rubber materials.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, preferred embodiments of the accumulator bladder according to the present invention will be described in detail with reference to the accompanying drawings.

However, in the embodiments described below,
The description is provided to facilitate or accelerate the understanding of the present invention, and is not described to limit the present invention.

In other words, each element disclosed in the embodiments described below includes all design changes and equivalent substitutions that fall within the spirit and technical scope of the present invention.

(Explanation of attached drawings)

FIG. 1 is a sectional view showing an embodiment of an accumulator bladder according to the present invention, in a no-load state.

FIG. 2A is a partial sectional view showing the manufacturing procedure of the embodiment shown in FIG. 1, and shows the bladder body 11 in a blow-molded state.

FIG. 2B is a partial sectional view showing the manufacturing procedure of the embodiment shown in FIG. 1, in which the diaphragm portion 11B and the fixing portion 11C of the bladder body 11 are attached to the bellows portion 11A after blow molding. The figure shows a state in which the poppet 12 is not yet attached to the bellows portion 11A.

FIG. 2C is a partial sectional view showing the manufacturing procedure of the embodiment shown in FIG. The holder 23 is shown attached to the fixed part 11C before being attached to the shell 21 after the poppet 12 is attached to the part 11A.

FIG. 3 is a cross-sectional view showing the usage state of the embodiment shown in FIG. 1, in which it is attached to the shell 21 and is in an unloaded state.

FIG. 4A is a cross-sectional view for explaining the operating state of the embodiment shown in FIG. It shows.

FIG. 4B is a cross-sectional view for explaining the usage state of the embodiment shown in FIG. It shows the state that has been applied.

(Configuration of Example)

First, the construction of an embodiment of an accumulator bladder according to the present invention will be described in detail with reference to FIGS. 1 to 4B.

Reference numeral 10 indicates a bladder for an accumulator according to the present invention, and a bladder body 11 is made by blow molding using an elastic plastic material (for example, polyamide elastomer or polyester elastomer) that has superior gas shielding properties compared to rubber materials. and a poppet 12 attached to the center of the outer peripheral surface of the bladder body 11 (the surface located on the liquid chamber 21B side when attached to the shell 21 described later). Incidentally, the reason why the poppet 12 is attached to the bladder body 11 is that when the poppet 12 is attached to the shell 21, which will be described later, the bladder body 11 is sucked into the liquid guide hole 25a of the liquid inlet/outlet member 25.
This is to prevent it from being damaged.

The bladder body 11 includes a bellows portion 11A including a central portion to which the poppet 12 is attached, and a bellows portion 11A.
A and after blow molding, the bellows part 11A
A diaphragm part 11B as an intermediate part that is inverted toward the bellows part 11A side on the outside of the diaphragm part 11
It includes a fixed part 11C as a peripheral part continuous with B.

Reference numeral 20 denotes an accumulator, and the accumulator bladder 10 according to the present invention
The internal space is divided into a gas chamber 21A and a liquid chamber 21B. That is, the accumulator bladder 10 according to the present invention has a diaphragm portion 11 of a bladder main body 11.
The outer peripheral surface of B is arranged along the inner peripheral surface of the shell 21 of the accumulator 20, and the fixing part 11 of the bladder body 11 is
After the outer circumferential surface of C is placed in contact with the inner circumferential surface of the shell 21 of the accumulator 20 via the O-ring 22, the fixed part 11C of the bladder body 11 is fixed by the holder 23.
By being pressed toward the inner peripheral surface of the shell 21 through the ring 22, it is arranged against the inner peripheral surface of the shell 21, and divides the internal space of the shell 21 into a gas chamber 21A and a liquid chamber 21B. There is.

A suitable working gas (for example, nitrogen gas) is supplied to the gas chamber 21A of the shell 21 through a gas supply port 24a.
After filling, the closing member 24 and the sealing member 2
4b by closing the gas supply port 24a.

The liquid chamber 21B of the shell 21 has a liquid guide hole 25a whose inner opening can be closed by the poppet 12.
liquid inlet/outlet member (so-called “oil port”)
25 are arranged. For this reason, the liquid chamber 21B can be connected to an appropriate liquid supply source ( (not shown), and an appropriate amount of liquid is supplied depending on the liquid pressure of the liquid supply source.

(Effect of the embodiment)

Further, with reference to FIGS. 1 to 4B, an embodiment of the accumulator bladder according to the present invention will be described in detail while briefly explaining the functions of the accumulator.

[0029] At the time of creation

Accumulator bladder 1 according to the present invention
0 has a structure in which the diaphragm part 11B is continuous with the bellows part 11A as shown in FIGS. 1 to 2C, so an elastic plastic material with superior gas shielding properties compared to rubber material is used. As a result, the accumulator can be made smaller and cheaper.

Accumulator bladder 1 according to the present invention
0 also means that the bladder body 11 has a bellows portion 11A and a diaphragm portion 11B as shown in FIGS. 1 to 2C.
Since it has a structure in which the parts are continuous, it can be produced by blow molding, and as a result, manufacturing efficiency can be improved.

[0032] At the time of installation

Accumulator bladder 1 according to the present invention
0, as shown in FIG. 3, the diaphragm part 11B of the bladder body 11 is arranged so as to be in contact with the inside of the shell 21, and the outer peripheral surface of the fixing part 11C is brought into contact with the O-ring 22 and pressed by the holder 23. The internal space of the shell 21 is divided into a gas chamber 21A and a liquid chamber 21.
Since it is divided into B and B, the work of attaching the shell 21 can be simplified.

[0034] When charging working gas

Accumulator bladder 1 according to the present invention
0, when attached to the shell 21 of the accumulator 20, the diaphragm portion 11B extends along the inner circumferential surface of the shell 21 and is provided with the bellows portion 11A, so that appropriate action can be performed via the gas supply port 24a. When gas is filled and sealed by the closing member 24 and the sealing member 24b, the diaphragm portion 11B is supported by the inner circumferential surface of the shell 21, and the bellows portion 11A is contracted so as to be folded over, as shown in FIG. 4A. Therefore, the accumulator bladder 10 according to the present invention can be prevented from being damaged by the gas pressure of the working gas when it is filled with the working gas.

[0036] No load

Accumulator bladder 1 according to the present invention
By screwing the threaded part of the liquid supply pipe into the threaded part 25b of the liquid inlet/outlet member 25, the accumulator 20 with No. 0 attached can be connected to an appropriate liquid supply source (not shown) through the liquid guide hole 25a. An appropriate amount of liquid is supplied according to the liquid pressure of the liquid supply source.

Accumulator bladder 1 according to the present invention
At this time, if there is no load, the diaphragm portion 11B of the bladder body 11 extends along the inner circumferential surface of the shell 21 (may be in substantial contact with it), as shown in FIG. The bellows part 11A is the gas chamber 2.
It protrudes toward 1A.

[0039] When inhaling liquid

When the liquid pressure of the liquid supply source increases compared to the no-load state, the accumulator bladder 10 according to the present invention has the bellows portion 11A of the bladder body 11 facing the gas chamber 21A (that is, in the "suction direction"). As shown by the arrow X, the pressure applied to both sides of the
That is, the gas pressure in the gas chamber 21A and the liquid chamber 21B
The liquid pressures) stop at a position where they are in equilibrium with each other (see Figures 3 and 4B).

Accumulator bladder 1 according to the present invention
0, at this time, the bellows portion 11A of the bladder body 11
and the diaphragm part 11B, so the bellows part 11A, the diaphragm part 11B, and the bellows part 1 are included.
It is possible to suppress stress (and strain) from concentrating on both the connecting portion of the diaphragm portion 1A and the diaphragm portion 11B, and as a result, the shape of the accumulator 20 can be reduced in size and its lifespan can be increased.

[0042] When discharging liquid

Accumulator bladder 1 according to the present invention
0 means that when the liquid pressure of the liquid supply source decreases compared to the no-load state or the liquid suction state, the bellows portion 11A gradually moves toward the liquid chamber 21B side (that is, the "discharge direction") as shown by arrow Y. The pressure applied to both sides (i.e., the gas pressure in the gas chamber 21A and the pressure in the liquid chamber 21A)
The liquid pressures (B) stop at a position where they are in equilibrium with each other (see Figures 3 to 4B).

Accumulator bladder 1 according to the present invention
0, at this time, the bellows portion 11A of the bladder body 11
and the diaphragm part 11B, so the bellows part 11A, the diaphragm part 11B, and the bellows part 1 are included.
It is possible to suppress stress (and strain) from concentrating on both the connecting portion of the diaphragm portion 1A and the diaphragm portion 11B, and as a result, the shape of the accumulator 20 can be reduced in size and its lifespan can be increased.

Therefore, in the accumulator bladder 10 according to the present invention, even if the bellows portion 11A repeatedly approaches and separates from the liquid inlet/outlet member 25 due to fluctuations in the liquid pressure of the liquid supply source, the bellows portion 11A It is possible to suppress stress (and strain) from concentrating on both the diaphragm portion 11B and the connecting portions of the bellows portion 11A and the diaphragm portion 11B, thereby making it possible to downsize the accumulator 20 and extend its life.

(Modification) In the above description, the bladder body 1
Although the case in which the bladder body is blow-molded using an elastic plastic material has been described, the present invention is not limited thereto. (ii) It also includes cases where the bladder body is molded using a conventional rubber material by an appropriate molding method.

In other words, the accumulator bladder according to the present invention includes at least a fixed part fixed to the inner circumferential surface of the shell by the holder, and a fixed part continuous to the fixed part and attached to the inner circumferential surface of the shell. As long as it includes a diaphragm part that extends along the inner circumferential surface of the shell under no load, and a bellows part that is continuous with the diaphragm part and is reversed toward the fixed part, the manufacturing procedure or material may be changed. It may be selected as desired.

[0048]

Effects of the Invention As is clear from the above, the bladder for an accumulator according to the present invention has a holder in which the peripheral edge is in contact with the inner circumferential surface of the shell of the accumulator, as specified in the section [Means for solving problems]. A bladder for an accumulator is fixed by a holder, in particular, a fixed part is fixed to the inner peripheral surface of the shell by a holder, and the bladder is connected to the fixed part and has no load when attached to the inner peripheral surface of the shell. (i) The fixed part and the diaphragm are provided with a diaphragm part that extends along the inner circumferential surface of the shell and a bellows part that is continuous with the diaphragm part and is inverted toward the fixed part side. This has the effect of suppressing stress concentration on the connecting portion of the diaphragm portion or the connecting portion of the diaphragm portion and the bellows portion.
i) It has the effect of extending the lifespan, and (iii) it has the effect of being able to be made using an elastic plastic material that has superior gas shielding properties compared to rubber materials.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing one embodiment of an accumulator bladder according to the present invention.

2A is a partial cross-sectional view showing the manufacturing procedure of the embodiment shown in FIG. 1; FIG.

2B is a partial cross-sectional view showing the manufacturing procedure of the embodiment shown in FIG. 1. FIG.

FIG. 2C is a partial cross-sectional view showing the manufacturing procedure of the embodiment shown in FIG. 1;

FIG. 3 is a sectional view showing the usage state of the embodiment shown in FIG. 1;

4A is a sectional view for explaining the operating state of the embodiment shown in FIG. 1. FIG.

4B is a sectional view for explaining the usage state of the embodiment shown in FIG. 1. FIG.

FIG. 5 is a sectional view showing a conventional example.

[Explanation of symbols]

Claims (1)

[Claims] Claim 1: A bladder for an accumulator in which the peripheral edge is in contact with the inner peripheral surface of the shell of the accumulator and is fixed by a holder, comprising: (a) a fixing part (11C) fixed to the inner peripheral surface of the shell by the holder; ,(b)
a diaphragm part (11B) that is continuous with the fixed part (11C) and extends along the inner peripheral surface of the shell in an unloaded state when attached to the inner peripheral surface of the shell;
) A bladder for an accumulator, comprising: a bellows part (11A) which is continuous with a diaphragm part (11B) and is inverted toward a fixed part (11C).