JPH047367Y2 - - Google Patents

Description

[Detailed description of the invention] Industrial application field The invention relates to an accumulator used for accumulating and buffering pressurized liquid, and in particular, it is used to detect when a bladder is at its permissible compression limit, when a bladder is damaged, or when an increase or decrease in gas injection pressure is detected. The present invention relates to a bladder type accumulator with a shutter type sensor that can be used.

BACKGROUND TECHNOLOGY A bladder-type acumulator has a bladder airtightly installed inside a container body, gas is filled into the bladder by a filling means, and liquid is moved into and out of the container body against the gas pressure inside the bladder. However, when the gas pressure in the bladder decreases due to gas permeation through the bladder, more liquid than the specified amount enters the main body of the container, the bladder is compressed beyond the allowable compression limit, and the air supply from the lid is The bladder will be damaged if it is pushed into the mouth.

If the bladder is damaged in this manner, gas will leak to the liquid side, and the accumulator will be unable to accumulate and buffer the pressurized liquid, resulting in a fatal deficiency for the accumulator.

Conventionally, a holder that protrudes into the bladder is provided on the lid of the container body, and a detector is provided at the tip of the holder. When the bladder is compressed to 1/4, it approaches or contacts the detector and reflects the ultrasonic waves emitted by the detector, and the reflected waves are detected and a signal is emitted.
-Refer to No. 16800).

Problems that the invention aims to solve Conventional bladder-type accumulators use ultrasonic waves for detection, which makes the structure of the detector complicated, and if oil gets into the bladder due to breakage,
Detection becomes impossible or inaccurate.

In addition, since the detector is activated by the approach or contact of the bladder, there is a considerable range of activation timing, and especially under high pressure, it may not operate accurately at the bladder's permissible compression limit, and it may be damaged. Sometimes.

In view of the above circumstances, it is an object of the present invention to provide a bladder-type accumulator with a shutter-type sensor that has a simple structure and can accurately detect the allowable compression limit, increase/decrease in gas injection pressure, or bladder damage.

Means for Solving the Problems The present invention fixes both leg ends of a U-shaped optical fiber that protrudes into the bladder and is accommodated in the holder to the lid of the container body, and A light-emitting part is provided, a light-receiving part is provided at the other leg end, a shutter is provided in the middle of the optical fiber, and a driving part for the shutter is provided with an elastic protection plate on the side of the holder. This is a bladder-type accumulator with a shutter-type sensor, characterized in that an elastic protection plate is located at a portion of the bladder that changes when the compression limit is reached.

Function The shutter is open when the bladder's allowable compression limit, set oil level, or bladder damage does not occur, so the light from the light emitting section reaches the light receiving section through the optical fiber, but when the allowable compression limit or set oil level is reached, the shutter is open. At the time of discharge, the bladder presses the drive section of the shutter, so the shutter closes and the light from the light emitting section is blocked. Also, if the bladder is damaged for some reason and liquid enters the gas chamber, the bladder will not press the shutter drive part, but instead the liquid will act as a shutter, blocking the light from the light emitting part and preventing it from reaching the light receiving part. It is possible to activate a switch that issues an alarm.

Example An embodiment of the present invention will be described with reference to the accompanying drawings.

In FIG. 1, reference numeral 1 denotes a container body, which is made of a rigid material such as metal and has a shape with high pressure resistance.

A bladder 2 is inserted into the container body 1 in the axial direction, and its flange portion 3 is sandwiched between the container body 1 and the lid 4.

This bladder 2 is made of a flexible elastic material such as rubber.

A holder 6 for an optical fiber 5 is arranged inside the bladder 2 in its longitudinal direction, and the end of the holder 6 is fixed to the lid 4 via a fixture 7. A U-shaped optical fiber 5 is disposed inside the holder 6, and both end portions 8 and 9 of the optical fiber 5 are
It is fixed to the lid 4.

A quartz glass fiber, a plastic fiber, etc. is used as the optical fiber 5, but the leg ends 8, 9
If it is connected with plastic, it will melt when the ambient temperature of the accumulator A becomes abnormally high, and it will also function as a temperature fuse, which is safe.

A light emitting section 1 is attached to one leg end 8 of the optical fiber 5.
0 is provided, and the other leg end 9 is provided with a light receiving section 11.
is provided.

A shutter 12 is provided in the middle of the optical fiber 5, and the shutter 12 is opened and closed by a drive section 13.

The drive unit 13 includes an elastic protection plate 15 provided on the gas hole 14 of the holder 6, and a pin 1 whose one end is connected to the elastic protection plate 15 and whose other end contacts the shutter 12.
6.

This drive part 13 is located in the movable part 2A of the bladder within the permissible compression limit or within the accumulator operating pressure range.

17 is a gas supply port, and the gas injected from this supply port 17 is passed through the gas passage 18 and the gas hole 14.
It is filled into the bladder through the

Reference numeral 109 denotes a liquid supply/discharge port, which is a liquid inlet/outlet, and inside thereof is a valve body 11 supported by a shaft 112.
1 is provided. This valve body 111 is connected to the spring 1
It is opened by the elasticity of the bladder 2 and closed by pressing due to the deformation inside the bladder 2.

Next, the operation of this embodiment will be explained. When gas is injected into the bladder 2 from the gas supply port 17 and a predetermined gas pressure is reached, the bladder 2 comes into close contact with the inner wall of the main body and is connected to the optical fiber 5 from the light emitting part 10. Light is sent and received by the light receiving section 11.

Then, operate the pump P and the tank (not shown)
When the liquid is pressurized into the supply/discharge port 109, the bladder 2
are compressed and deformed by the hydraulic pressure, but do not come into contact within the allowable compression limit or the set oil amount, so the shutter 12 remains open and the light from the light emitting section 10 passes through the optical fiber 5. The light reaches the light receiving section 11.

However, if the sealed gas exceeds the permissible compression limit of the leakage bladder 2 during permeation, the movable portion 2a of the bladder presses the drive portion 13 and the shutter 12, causing the shutter 12 to close. , the light from the light emitting unit 10 that has passed up to that point is
Since the light is blocked and does not reach the light receiving section 11, a detection signal is generated, which closes a control valve (not shown) and issues an alarm. At this time, by filling the bladder 2 with gas up to a predetermined gas pressure, it is possible to avoid using the bladder 2 beyond its compression limit, and the bladder is also not damaged. When operating the sensor within the operating pressure range of the accumulator, the set pressure of the pressure switch PS is set to the lower limit set pressure and the upper limit set pressure.

Here, the lower limit set pressure refers to a set pressure lower than the sensor operating pressure, and the upper limit set pressure refers to a set pressure higher than the sensor operating pressure.

If the gas injection pressure in the bladder decreases, the sensor operating pressure will operate at a pressure lower than the lower limit setting pressure, and if the pressure increases due to a rise in temperature, the sensor operating pressure will operate at a pressure higher than the upper limit operating pressure. Since it is activated, it is possible to detect increases and decreases in the injection gas pressure.

When the bladder is damaged, even if the pressure on the hydraulic side is reduced, the oil that has entered the bladder will cause a shutter effect, and if the fluid does not enter the bladder, the shutter will operate due to the deformation of the bladder, causing the light emitting part 10 to Since the light remains blocked and does not reach the light receiving section 11, the detection signal continues to be emitted, allowing bladder damage to be detected. In this case, the bladder can be replaced and filled with gas.

Effects of the Invention Since the present invention is constructed as described above, the structure is simple, and even if the bladder is deformed, the optical fiber is protected by the holder, so it will not be damaged. Furthermore, when the bladder reaches its permissible compression limit, the shutter driving section is pressed against the movable portion of the bladder to reliably close the shutter, making it possible to accurately detect the limit.

At this time, the movable portion of the bladder closes the shutter while making surface contact with the elastic protector of the driving portion of the shutter, so the load per unit area at the contact portion of the bladder is smaller than in the case of point contact. Therefore, since concentrated stress is not applied to the bladder, accidents that break the bladder can be prevented.

Additionally, when the bladder is damaged, the light passing through the optical fiber is blocked by the liquid that has entered the bladder.
Bladder damage can be detected with certainty.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view showing an embodiment of the present invention. A...Accumulator, 1...Container body, 2...
...bladder, 4...lid, 5...optical fiber, 10...
... Light emitting section, 11 ... Light receiving section, 12 ... Shutter.

Claims (1)

[Scope of claims for utility model registration] 1. The lid of the container body protrudes into the bladder, and
Both leg ends of the U-shaped optical fiber housed in the holder are fixed, a light emitting part is provided at one leg end,
A light receiving part is provided at the other leg end, a shutter is provided in the middle of the optical fiber, and a driving part of the shutter is provided with an elastic protection plate on the side of the holder, and the elastic protection plate of the drive part is provided. A bladder-type accumulator with a shutter-type sensor, characterized in that it is located at a portion of the bladder that changes when the compression limit is reached. 2. A bladder-type accumulator with a shutter-type sensor according to claim 1, wherein the leg end of the optical fiber is a plastic connection.