JPH0547281Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a bladder type accumulator, and for example, to an accumulator suitable for being connected to a hydraulic pressure supply pipe in a power sling device for a vehicle.

(Conventional technology) To prevent pulsation from hydraulic sources such as pumps,
A bladder type accumulator is one of the accumulators connected to the hydraulic pressure supply piping. this is,
a hollow outer shell having a fluid inlet and an outlet; an inner shell disposed within the outer shell and together defining a passageway communicating with the outlet; an inner shell disposed within the outer shell and attached to the inner shell; It consists of a closed bladder. The bladder together with the inner shell defines a closed space, and together with the outer shell defines passages communicating with the inlet and the passage, respectively (for example, Japanese Utility Model Application No. 61-200902).

High-pressure gas is sealed in the sealed space, and the accumulator is introduced into the hydraulic pressure supply piping. When hydraulic fluid enters the inlet of the accumulator, the bladder acts on the fluid to balance the pressure of the fluid with the pressure of the gas in the enclosed space. In this way, the pulsating fluid flows out of the outlet.

(Problems to be Solved by the Invention) In general, pumps tend to generate abnormal noises during operation, and if the pump happens to be near the passenger compartment of an automobile, it will cause discomfort to the occupants. In order to eliminate this discomfort, it is necessary to reduce the abnormal noise.

When an accumulator is used by being incorporated between a pump and an operating means such as a power cylinder, it is preferable if abnormal noise can be reduced by the accumulator itself, since there is no need to take special measures to reduce the abnormal noise. . From this point of view, the requirements that the accumulator must satisfy are that the volume of the accumulator is large and that the pressure of the gas sealed in the accumulator is low.

However, by increasing the volume of the accumulator,
If the pressure of the sealed gas is lowered, when high-pressure hydraulic fluid acts suddenly on the accumulator from the pump, for example when sudden steering is performed in a power swaying device, the responsiveness of the accumulator will deteriorate and the original function of the accumulator may be impaired. There is a risk that you will not be able to perform to your full potential.

It is an object of the present invention to provide a bladder type accumulator that can reduce pump noise and cope with sudden pressure increases.

(Means for Solving the Problems) A bladder type accumulator according to the present invention includes a hollow outer shell having a fluid inlet and an outlet, and an inner shell disposed within the outer shell, the passage communicating with the outlet. an inner shell which is disposed in the outer shell and is attached to the inner shell, which together defines a sealed space with the inner shell, and which communicates with the inlet and the passageway, respectively. a bladder defining a passage together with the outer shell; and a retainer disposed within the sealed space, the restricting hole partitioning the sealed space into a first chamber on the inlet side and a second chamber on the outlet side. and a retainer having a retainer. A fluid is sealed in the first chamber and a gas is sealed in the second chamber.

The fluid sealed in the first chamber is liquid or gas. When the fluid is a liquid, the retainer is provided with a small diameter return path for returning the liquid that has flowed from the first chamber into the second chamber through the throttle hole of the retainer to the first chamber. When the fluid is a liquid, the first chamber can be filled with the liquid or partially filled with gas. If the fluid in the first chamber is a gas, this gas is the same as the gas enclosed in the second chamber.

(Function and Effect) As a result of filling the second chamber of the closed space with high pressure gas,
The pressure inside the closed space is maintained at the same level.

When hydraulic fluid under normal pressure enters the inlet of the accumulator, the bladder is substantially deformed so that there is no substantial flow of fluid from the first chamber to the second chamber. The hydraulic fluid is subjected to the pressure of the closed space via the bladder, and pulsation of the hydraulic fluid is absorbed. The hydraulic fluid then flows out the outlet.

When the pressure of the hydraulic fluid increases rapidly, the bladder deforms, and this deformation compresses the fluid in the first chamber, which flows into the second chamber through the restrictor hole in the retainer. At this time, the hydraulic fluid loses some of its energy due to the resistance to deformation of the bladder and the resistance as the fluid flows through the throttle hole. The hydraulic fluid whose pressure has been equalized in this way flows out from the outlet.

When a sudden pressure rise occurs, the energy of the hydraulic fluid can be dissipated due to the resistance to deformation of the bladder itself and the resistance when the fluid in the first chamber passes through the restrictor hole of the retainer. It can equalize the pressure of the hydraulic fluid flowing out of the outlet and suppress pulsation.

Increase the volume of the sealed space of the accumulator,
Even if the pressure is kept low, it is possible to cope with a sudden pressure increase, so on the one hand, the function of the accumulator can be fully demonstrated, and on the other hand, the effect of reducing abnormal noise can be obtained by the accumulator itself.

(Example) As shown in FIG. 1, the bladder type accumulator includes an outer shell 10, an inner shell 12,
It includes a bladder 14 and a retainer 16.

The outer shell 10 is formed in a hollow shape and has a fluid inlet 18 and an outlet 20. In the illustrated embodiment, the outer shell 10 has a first
It consists of a shell part 11a and a second shell part 11b. The second shell part 11b is welded to the first shell part 11a after parts such as an inner shell and a bladder, which will be described later, are housed in the first shell part 11a.

The inner shell 12 is arranged within the outer shell 10. In the illustrated embodiment, the inner shell 12 includes a chamber forming portion 13a formed in a cup shape;
Outlet 2 of the outer shell 10 from the chamber forming part 13a
It consists of a cylindrical injection part 13b extending through 0. The flange 13c is at the lower end of the chamber forming part 13a,
It projects radially outward. The outer peripheral surface of the flange 13c has an octagonal shape, as shown in FIG.

When the inner shell 12 is placed inside the outer shell 10, the flange 13c is connected to the ridge 11 provided on the outer shell 10 via a second retainer, which will be described later.
c, and the corner portion of the outer peripheral surface of the flange 13c contacts the inner peripheral surface of the outer shell 10. A passage 22 is defined by the chamber forming portion 13a and the outer shell 10. Then, a gap 24 is formed between the side of the outer peripheral surface of the flange 13c and the inner peripheral surface of the outer shell 10. This gap 24 becomes a passage through which the hydraulic fluid flows.

In the illustrated embodiment, the ring 26 is attached to the flange 1
3c and the second shell portion 11b of the outer shell, and firmly fixes the inner shell 12. The gap 24 is a hole 27 provided in the ring 26.
It communicates with passage 22 through.

The bladder 14 is formed of rubber into a cup shape and is disposed within the outer shell 10. A radially outwardly directed rim 13d projects from the flange 13c of the inner shell 12, and an inwardly directed rim 15a is provided on the bladder 14. This rim 15a is attached to the inner shell 12.
The bladder 14 is attached to the inner shell 12 by fitting into the rim 13d of the inner shell 12. two pobets 2
8 and 30 are attached to the pressure receiving part 15b at the center of the bladder 14.

The bladder 14 together with the inner shell 12 defines a closed space 32 , and together with the outer shell 10 defines a passage 34 communicating with the inlet 18 . The passage 34 communicates with the passage 22 via the gap 24 and the hole 27 in the ring.

The retainer 16 is formed into a cup shape,
It is arranged in a sealed space 32, and the sealed space 32 is divided into a first chamber 33a on the inlet 18 side and a second chamber 33a on the outlet 20 side.
It is partitioned into a chamber 33b. The retainer 16 has a throttle hole 36 at its center and a plurality of through holes 37 at its outer periphery.

In the illustrated embodiment, a second retainer 38 circumscribes the bladder 14 . Second retainer 38
The flange 39a is connected to the protuberance 1 of the outer shell 10.
It is held on 1c. Flange 39a
has the same octagonal shape as the flange 13c of the inner shell 12. A hole 40 is bored in the center introduction part 39b of the retainer 38. second retainer 3
8 prevents the bladder 14 from deforming due to the pressure of the gas within the closed space 32. Therefore, it is preferable to provide this retainer 38.

After storing oil in the lower part of the first chamber 33a of the sealed space 32, high pressure gas such as nitrogen is injected from the valve core 42 of the injection part 13b of the inner shell 12, and the upper part of the first chamber 33a and the second chamber are filled with oil. 33
b and cap 44.

The basic configuration of the embodiment shown in FIG. 2 is the same as that shown in FIG. In this embodiment, the fluid sealed in the first chamber 33a of the closed space 32 is gas. Therefore, only the throttle hole 36 is provided in the retainer 16. In this embodiment, the closed space 32
For example, high-pressure nitrogen is filled in the entire area.

When hydraulic fluid under normal pressure enters through the inlet 18 of the accumulator shown in FIG. 1, a portion of the hydraulic fluid acts on the bladder 14 through the hole 40 in the retainer 38, smoothing out the pulsations. And the hydraulic fluid is in passage 3
4. The liquid passes through the gap 24 and the hole 27 to reach the passage 22, and flows out from the outlet 20. At this time, the bladder 14 hardly deforms.

When the hydraulic fluid whose pressure has suddenly increased enters from the inlet 18, the speed of the hydraulic fluid flowing from the hole 40 toward the bladder 14 increases, causing the bladder 14 to deform. By deforming the bladder 14, first the first chamber 33
Nitrogen in a passes through the throttle hole 36. Bladder 14
As the deformation becomes even larger, the oil in the first chamber 33a passes through the throttle hole 36, and the bladder 14 finally hits the retainer 16. The oil that has entered the second chamber 33b from the first chamber 33a passes through the drain hole 37 and returns to the first chamber 33a.

In the embodiment of FIG. 1, the energy of the hydraulic fluid is dissipated in three stages. That is, the first stage is due to the resistance of oil passing through hole 40, the resistance of deforming bladder 14, and the resistance of nitrogen passing through throttle hole 36. In the second and third stages, in addition to the resistance when the oil passes through the hole 40 and the resistance when deforming the bladder 14, respectively, in the second stage, due to the resistance when the oil passes through the throttle hole 36, In the third stage, the impact occurs when the bladder 14 hits the retainer 16. In this way, the energy due to the pressure increase in the hydraulic fluid is dissipated and the pulsations are smoothed out.

In the embodiment of FIG. 2, the first and third steps are
The energy of the hydraulic fluid is dissipated in stages.

In the embodiment shown in FIG. 1, by arranging the entire accumulator at an angle, it is possible to change the degree of energy dissipation in the second stage.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of the accumulator, FIG. 2 is a cross-sectional view of another embodiment of the accumulator, and FIG. 3 is a cross-sectional view taken along line 3--3 in FIG. 1, showing the upper half. 10... Outer shell, 12... Inner shell, 14... Bladder, 16... Retainer, 18...
...Inflow port, 20...Outflow port, 32...Closed space,
36...Aperture hole.

Claims (1)

[Scope of utility model registration request] a hollow outer shell having a fluid inlet and an outlet, an inner shell disposed within the outer shell that together with the outer shell defines a passageway communicating with the outlet, and an inner shell disposed within the outer shell; A bladder attached to the inner shell, which together with the inner shell defines a sealed space,
a bladder that, together with the outer shell, defines passages that communicate with the inlet and the passage, respectively; and a retainer that is disposed in the sealed space and connects the sealed space to a first chamber on the inlet side and the outlet. a retainer having a throttle hole partitioned into a second chamber on the side, the first chamber being filled with fluid, and the second chamber filled with gas.