JPH08251688A - Method and device for equalizing pressure of underwater sound source device and gas transmitting filter - Google Patents

Abstract

PURPOSE: To provide a method and a device for an underwater sound source device to equilibrate internal pressure with water pressure, and a gas premeable filter used therefor. CONSTITUTION: In the pressure equalizing method, the internal pressure of an enclosure 2 in the underwater sound source device constituted of surrounding the rear face of an oscillation part for emitting sound waves into water by the enclosure 2 is equalized with water pressure applied to the oscillation part. Gas is sealed into the enclosure 2 at pressure higher than the water pressure corresponding to the underwater depth of the enclosure 2 and gas is exhausted from the enclosure 2 by opening a discharge valve 14 into water.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an underwater sound source device for radiating sound into water, and more particularly to a method for equalizing an underwater sound source device for balancing internal pressure with water pressure, the device and a gas permeable filter used therefor. is there.

[0002]

BACKGROUND OF THE INVENTION Acoustics are sometimes used to probe underwater such as oceans, rivers and ponds. In contrast to the fact that light and electromagnetic waves do not reach far in water, sound propagates better in water than in air, making it suitable for remote exploration. In the acoustics, low frequencies below the audible band have been attracting attention in recent years, but a sound source that generates low frequencies with high sound pressure is required to reach a long distance.

The underwater sound source device developed for this purpose is one in which the back surface of a vibrating section that radiates sound waves in water is surrounded by an enclosure. In order to absorb the volume change of the enclosure due to the vibration of the vibrating section in the enclosure. Filled with an elastic gas. The vibrating part may have its perimeter fixed to the enclosure, but in order to generate low frequencies with high sound pressure, a vibrating plate having rigidity is used, and the perimeter of this vibrating plate is slid with respect to the enclosure. It is preferable to make it movable and to reciprocate the diaphragm in the direction of water to radiate sound waves into the water. Further, the underwater side of the diaphragm may be covered with a flexible acoustically transparent film to form an oil chamber between the diaphragm and the diaphragm, and the oil may be sealed in the oil chamber. This oil has an acoustic impedance equal to that of water, and when the diaphragm is reciprocally oscillated in the direction of the acoustically transparent film, the acoustic impedance is matched on both sides of the acoustically transparent film, so that the sound is efficiently emitted into the water. can do.

To vibrate the vibrating section, a reciprocating actuator such as a hydraulic cylinder is used.

[0005]

By the way, although the enclosure is filled with gas, the vibrating section receives water pressure. Water pressure varies greatly with water depth. When moving and using an underwater sound source, it is necessary to compensate for the internal pressure of the enclosure against changes in water pressure and to balance the pressure. Such pressure equalization of the underwater sound source is an element that leads to a reduction in the driving force of the actuator and a reduction in the weight of the vibrating portion, and is also important for obtaining a wide use range from low depth to high depth.

Conventionally, pressure equalization is achieved by connecting a flexible gas chamber made of rubber or bellows to the enclosure and expanding and contracting the gas chamber with water pressure. However, in order to generate high sound pressure at low frequencies, the enclosure requires a large volume. The above method is not suitable as a pressure equalizing method for such a large volume enclosure because the gas chamber becomes huge. In addition, there is a type in which the vibrating portion is rigidly fixed to the enclosure to resist water pressure and the actuator is driven strongly, but in this type, reduction in driving force and weight reduction cannot be expected.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to solve the above problems and provide a pressure equalizing method for an underwater sound source device for balancing the internal pressure to the water pressure, a device therefor, and a gas permeable filter used therefor.

[0008]

In order to achieve the above-mentioned object, the present invention uses the enclosure internal pressure of an underwater sound source device in which the back surface of a vibrating section that radiates sound waves in water is surrounded by an enclosure, to the water pressure received by the vibrating section. In the pressure equalization method of balancing, gas is enclosed in the enclosure at a pressure equal to or higher than the water pressure corresponding to the diving depth, and a release valve communicating with water from the enclosure is opened to release the gas.

The discharge valve may be opened when water is dipped to a predetermined depth by previously filling a gas on the water in the enclosure at a pressure equal to or higher than the water pressure corresponding to the predetermined diving depth.

A compensating tank for storing high-pressure compressed gas is connected to the enclosure via an injection valve, and when the enclosure internal pressure is lower than water pressure, the injection valve is opened to inject gas into the enclosure so that the enclosure internal pressure is lower than water pressure. The release valve may be opened when high.

The apparatus is an underwater sound source apparatus which emits sound waves into water by reciprocating the diaphragm in the water by enclosing the opposite side of the diaphragm facing one surface in water with an enclosure. In a pressure equalizer that balances the internal pressure of the enclosure with the water pressure received by the vibrating section,
A compensating tank that stores high-pressure compressed gas is connected to the enclosure via an injection valve, and a discharge valve that communicates from the enclosure to water is provided.When the enclosure internal pressure is lower than water pressure, the injection valve is opened, and the enclosure internal pressure is higher than water pressure. A pressure controller for opening the discharge valve is sometimes provided.

The underwater side of the diaphragm may be covered with a flexible acoustically transparent film to form an oil chamber between the diaphragm and the diaphragm, and oil may be sealed in the oil chamber.

It is also possible to partition the interior of the enclosure with a flexible blocking film facing the diaphragm to form a sub oil chamber between the diaphragm and the sub oil chamber, and to fill the sub oil with oil.

A check valve that opens only when the upstream side has a high pressure may be provided downstream of the discharge valve.

A gas permeation filter for permeating gas and blocking water may be provided downstream of the discharge valve.

A gas permeation filter used for pressure equalization of an underwater sound source device has a cell having a gas inlet and a liquid inlet,
A continuous polymer porous film that transmits gas and blocks water is divided into a gas chamber and a liquid chamber, and a punching metal is superposed on the gas chamber side of the continuous polymer porous film.

Alternatively, in a housing having a gas introducing port and a liquid introducing port, a filter element constructed by laminating a porous metal plate on one surface of a polymer continuous porous film which transmits gas and blocks water, Arranged in multiple stages so that the films and the metal plates face each other, the liquid flow path formed between the films is communicated with the liquid introduction port, and the gas flow path formed between the metal plates is the gas introduction port. It was made to communicate with.

[0018]

With the above construction, the internal pressure of the enclosure becomes equal to or higher than the hydraulic pressure corresponding to the diving depth, so when the release valve is opened, gas is released and the internal pressure of the enclosure is balanced with the hydraulic pressure. It can handle high depth without changing the enclosure volume.

If the discharge valve is opened when the gas is sealed in advance on water and the dive is performed to a predetermined depth, the equipment for sealing the gas and the enclosure are separated and it is not necessary to detect the water pressure. The structure of the pressure equalizer is simplified.

When the compensating tank is connected to the enclosure, the pressure can be equalized by operating the injection valve and the discharge valve when the pressure inside the enclosure is lower or higher than the water pressure.
It can follow changes in diving depth.

In the case of an underwater sound source device in which the diaphragm reciprocates in the direction of water, the diaphragm cannot be fixedly supported by the enclosure, so that the diaphragm is supported exclusively by the internal pressure of the enclosure. According to the present invention, the pressure controller can perform pressure equalization by operating the injection valve and the discharge valve both when the internal pressure of the enclosure is lower than the water pressure and when it is high.
Even pressure is always maintained regardless of water pressure.

Even when sound waves are emitted through the oil chamber, the pressure in the oil chamber can be equalized by equalizing the internal pressure and the water pressure in the enclosure.

By enclosing the oil in the sub oil chamber, the diaphragm vibrates only in the oil. Further, since it is partitioned from the sub oil chamber by a flexible film, when the internal pressure of the enclosure is equalized, the sub oil chamber is also equalized.

Since the check valve is opened only when the upstream side has a high pressure, it is closed on the downstream side, that is, when the water pressure is higher, so that the inflow of water is prevented.

Since the gas permeable filter permeates the gas and blocks the water, the inflow of water is prevented when the gas is discharged into the water.

The polymer continuous porous film permeates gas and blocks water. Punching metal does not impede gas permeation and can support films that are compressed when water pressure is higher than atmospheric pressure.

A wide transmission area can be secured by arranging the filter elements in multiple stages such that the films and the metal plates face each other.

[0028]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the accompanying drawings.

As shown in FIG. 1, an enclosure 2 is incorporated in the underwater sound source device 1, and one side of the enclosure 2 is formed of a vibration transmitting film 3. Inside the enclosure 2, a vibration plate 4 facing the vibration transmission film 3 is provided. The diaphragm 4 is almost equal to the inner diameter of the enclosure 2 and is allowed to reciprocate by sliding, and also partitions the enclosure 2 into two. The vibration permeable membrane 3 side of the vibration plate 4 is called an oil chamber 5, and the back side of the vibration plate 4 is called a gas chamber 6. Acoustic oil transmission oil is enclosed in the oil chamber 5. The gas chamber 6 is filled with compressed gas. A rod 7 is attached to the back side of the diaphragm 4, and the rod 7 penetrates the opposite side of the enclosure 2 and is inserted into a hydraulic cylinder 8. A piston 9 is provided in the hydraulic cylinder 8, and a rod 7 is attached to the piston 9. A hydraulic control device (not shown) can reciprocate the piston 9 at a low frequency to reciprocate the diaphragm 4 in the direction of the sound transmitting film 3.

The principle of acoustic radiation in water of the underwater sound source device 1 is that the sound due to the reciprocating motion of the diaphragm 4 propagates in the acoustic oil in the oil chamber 5 and the acoustic impedances on both sides of the acoustic transmission film 3 are matched. Since the sound is apparent, the sound transmission film 3
It passes through and is emitted into the water.

A gas sealing line 11 communicating with the outside of the underwater sound source device 1 is connected to the gas chamber 6, and a valve 12 is provided in the gas sealing line 11. Valve 12
Is opened only when the compressed gas is filled on the water, and closed when used in the water. Further, the gas chamber 6 is connected to another gas discharge line 13 communicating with the outside of the underwater sound source device 1, and the gas discharge line 13 is provided with a discharge valve 14 and a check valve 15. The discharge valve 14 is closed until the underwater sound source device 1 dives to a predetermined depth, and then opened for pressure equalization. The check valve 15 closes the opening when the large diameter side of the opening has a high pressure,
When the small diameter side has a high pressure, the spherical member opens the opening, so that passage in only one direction from upstream to downstream is allowed. In the gas exhaust line 13, the gas chamber 6 is upstream and the outside of the underwater sound source device 1 is downstream.

When the underwater sound source device 1 is used in water, a high pressure cylinder or the like is used to compress the water pressure at a predetermined depth into the gas chamber 6 through the gas sealing line 11 at a high pressure. Enclose the gas. As the compressed gas, nitrogen gas, helium gas or the like having good compressibility is used. In the underwater sound source device 1 in which the compressed gas is sealed in the gas chamber 6 at a high pressure, the vibration plate 4 is largely pushed to the outside because the outside pressure of the vibration permeable membrane 3 is low on the water or during diving. In order to avoid this, the piston 9 is restricted in the hydraulic cylinder 8 and the diaphragm 4 does not go outside more than necessary.

After diving the underwater sound source device 1 to a predetermined depth in water, the discharge valve 14 of the gas discharge line 13 is opened. By discharging the high-pressure compressed gas, the internal pressure of the gas chamber 6 is balanced with the water pressure.

In this case, when the underwater sound source device 1 is moved in the direction of shallow depth, the pressure equalization can be maintained by further discharging the compressed gas. Therefore, when moving and using the underwater sound source device 1, it is preferable to start from the deepest place and gradually decrease the depth.

Next, an embodiment in which the internal structure of the enclosure 2 is modified will be described.

In the underwater sound source device 1a of FIG. 2, the same members as those of the underwater sound source device 1 of FIG. 1 are designated by the same reference numerals, and the description thereof will be omitted. The underwater sound source device 1a
Unlike the underwater sound source device 1 in FIG. 1, a flexible film 21 having flexibility is provided on the back side of the diaphragm 4. A partition between the diaphragm 4 and the flexible film 21 is a sub oil chamber 22.
2 is filled with oil. The compartment on the back side of the flexible membrane 21 is the gas chamber 23. The sound radiation and the pressure equalization method of the underwater sound source device 1a are the same as those of the underwater sound source device 1.

In the underwater sound source device 1a, since the gas chamber 23 and the sub oil chamber 22 are partitioned by the flexible film 21, the internal pressure of the gas chamber 23 and the sub oil chamber 22 are kept equal. When the gas chamber 23 is filled with the compressed gas at high pressure, the flexible film 21 swells toward the diaphragm 4, and when the internal pressure of the gas chamber 23 and the water pressure are balanced, the flexible film 21 does not swell.

The underwater sound source devices 1 and 1a have a simple structure because they do not have complicated members for enclosing and discharging gas.
Further, it is downsized and can be used at a deep depth.

Next, an underwater sound source device capable of increasing the internal pressure of the sound source by providing a tank for compressed gas will be described.

As shown in FIG. 3, the underwater sound source device 31
Is provided with an enclosure 32 in which a compressed gas is enclosed, and one side of the enclosure 32 is configured with a vibrating portion 33 capable of vibrating in and out. An actuator 34 that vibrates the vibrating portion 33 is provided in the enclosure 32. The enclosure 32 corresponds to the gas chamber 6 of FIG. 1, and the actuator 34 corresponds to the hydraulic cylinder 8. The vibrating section 33 may be composed of only the vibrating plate 4, or may be composed of the vibrating plate 4, the sound transmitting film 3 and the acoustic oil. In order to efficiently radiate sound into the water from the vibrating section 33, it is necessary to balance the internal pressure of the enclosure 32 with the water pressure.

The underwater sound source device 31 is provided with a compensation tank 35 for storing compressed gas at high pressure. Compensation tank 3
5 is connected to the enclosure 32 via a first solenoid valve (injection valve) 36. The enclosure 32 is connected to the outside of the underwater sound source device 31 via a second electromagnetic valve (release valve) 37, a gas permeable filter 38, and a check valve 15. Check valve 1 arranged downstream of the second solenoid valve 37
5 is the same as that used in the underwater sound source device 1 of FIG. The gas permeation filter 38 permeates gas and blocks water, the details of which will be described later. The gas permeable filter 38 is
If it is downstream of the second electromagnetic valve 37, it can be used either upstream or downstream of the check valve 15 or on both sides.
The pressure controller 39 is connected to a pressure sensor (not shown) that detects the internal pressure of the enclosure and a pressure sensor (not shown) that detects the water pressure. When the internal pressure of the enclosure 32 is lower than the external water pressure, the first solenoid valve 36 is connected.
And the second solenoid valve 37 is opened when the internal pressure is higher than the water pressure.

When the internal pressure of the enclosure 32 is lower than the external water pressure, the first electromagnetic valve 36 is opened and the high pressure compressed gas in the compensation tank 35 is injected into the enclosure 32. When the pressure difference detected by the pressure sensor is within the allowable range,
The first solenoid valve 36 is closed. On the contrary, when the internal pressure of the enclosure 32 is higher than the water pressure, the second electromagnetic valve 37 is opened and the gas is released into the water through the gas permeable filter 38 and the check valve 15. When the pressure difference detected by the pressure sensor is within the allowable range, the second solenoid valve 37 is closed.

According to this structure, even if the depth of the underwater sound source device 31 changes up and down, the difference between the internal and external pressures is kept within the allowable range.

The gas permeable filter 38 will be described in detail.

As shown in FIG. 4, the gas permeable filter 38 has a cell 43 having a gas inlet 41 and a liquid inlet 42, which is partitioned by a continuous porous film 44 made of a polymer such as polytetrafluoroethylene. ing. The gas inlet 41 is connected to the upstream side, that is, the second solenoid valve 37 in FIG. The liquid introduction port 42 is connected to the downstream side, that is, the check valve 15 or the outside. Continuous porous film 44
Is sandwiched by metal laths 45 from both sides. On the upstream metal lath 45, a punching metal 46 having a large number of holes formed in a metal plate is superposed. A liquid chamber 42a is formed in the cell 43 between the continuous porous film 44 and the liquid introduction port 42, and a gas chamber 41a is formed in the cell 43 between the continuous porous film 44 and the gas introduction port 41. To be done.

When the upstream side is under high pressure, the gas permeates through the holes of the punching metal 46, and the continuous porous film 4
Passes through 4 and exits downstream. Conversely, when the downstream side has a high pressure, water is blocked by the continuous porous film 44 and cannot escape to the upstream side. Although the continuous porous film 44 is a thin film, it is supported by the punching metal 46 and is not damaged by being pressed by water.

In the underwater sound source devices 1, 31, etc., the discharge port of the pipe for discharging gas to the outside is directed downward. This is to prevent water from flowing in through the discharge port. In particular, if the underwater sound source devices 1 and 31 have a discharge port at the bottom, the discharged gas is not immediately discharged to the water and is collected, so that the water is well prevented from flowing into the discharge port. However, since the underwater sound source devices 1 and 31 are towed underwater, their postures change. When the posture changes, the gas around the discharge port escapes to the water. In addition, water may flow in even if the discharge port is directed downward. Underwater sound source device 1, 3
1. When water flows into the inside, since this water is water in the natural environment, it contains impurities, salt, etc., and causes problems such as pollution and rust. By providing the gas permeable filter 38 as in the present invention, such inflow of water is prevented.

The gas permeable filter 38 can secure the amount of passing gas by making the basic structure of FIG. 4 multistage. That is, as shown in FIG. 5, in the laminated gas permeation filter 51, the continuous porous film 44, the metal lath 45, and the punching metal 46 are stacked, and the gas passages 52 and the liquid passages 53 are alternately sandwiched to form a multi-stage. Is formed in. The gas introduction port 54 provided on one side in the axial direction communicates with the shaft center portion, and the gas flow path 5 extends radially outward from the shaft center portion.
Liquid introduction port 5 branched into two and provided on the opposite side in the axial direction
5 communicates with the outer peripheral portion, and is branched into the liquid flow path 53 from the outer peripheral portion toward the inner side in the radial direction. With this configuration, a large surface area of the gas permeable portion is secured and concentrated, so that the laminated gas permeable filter 51 can pass a large amount of gas even if it is small.

[0049]

The present invention exhibits the following excellent effects.

(1) It is not necessary to strengthen the vibrating section, the underwater sound source is made lighter, and the driving force of the actuator is reduced.

(2) Even at a high depth, the pressure can be equalized with high accuracy, and as a result, the output sound pressure can be obtained with a high gain.

[Brief description of drawings]

FIG. 1 is a configuration diagram of an underwater sound source device showing an embodiment of the present invention.

FIG. 2 is a configuration diagram of an underwater sound source device showing a modified example of the present invention.

FIG. 3 is a configuration diagram of an underwater sound source device showing another embodiment of the present invention.

FIG. 4 is a sectional view of the gas permeable filter of the present invention.

FIG. 5 is a cross-sectional view of a laminated gas permeation filter of the present invention.

[Explanation of symbols]

 2 Enclosure 3 Sound Transmission Membrane 4 Vibration Plate 5 Oil Chamber 6 Gas Chamber 14 Release Valve

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Koji Sonehara 3-1-1, Toyosu, Koto-ku, Tokyo Ishikawajima Harima Heavy Industries Co., Ltd. Toni Technical Center (72) Inventor Manu Muto 3-chome, Toyosu, Koto-ku, Tokyo No. 1-15 Ishikawajima Harima Heavy Industries Co., Ltd. Toni Technical Center (72) Inventor Toshio Kojima 3-15-15 Toyosu, Koto-ku, Tokyo Ishikawajima Harima Heavy Industries Co., Ltd. Toji Technical Center (72) Inventor Tada Torao Ishikawajima Harima Heavy Industries Co., Ltd. Toni Technical Center, 3-15-15 Toyosu, Koto-ku, Tokyo

Claims (10)

[Claims] 1. A pressure equalizing method for balancing the internal pressure of the enclosure of an underwater sound source device in which a back surface of a vibrating section that radiates sound waves into water is surrounded by an enclosure, to a diving depth within the enclosure. A pressure equalizing method for an underwater sound source device, characterized in that a gas is sealed at a pressure equal to or higher than a corresponding water pressure, and a discharge valve communicating with water from this enclosure is opened to discharge the gas. 2. A gas is sealed in advance in water in the enclosure at a pressure equal to or higher than a water pressure corresponding to a predetermined diving depth, and the release valve is opened when diving to a predetermined depth. The pressure equalizing method for an underwater sound source device according to claim 1. 3. A compensating tank for storing high-pressure compressed gas is connected to the enclosure via an injection valve, and when the enclosure internal pressure is lower than water pressure, the injection valve is opened to inject the gas into the enclosure so that the enclosure internal pressure is The pressure equalizing method for an underwater sound source device according to claim 1, wherein the discharge valve is opened when the pressure is higher than the water pressure. 4. The internal pressure of the enclosure of an underwater sound source device, wherein the opposite side of a diaphragm facing one surface in water is surrounded by an enclosure, and the diaphragm is reciprocally moved in the water direction to radiate sound waves into the water. In a pressure equalizer that balances the water pressure received by the vibrating section, a compensating tank that stores high-pressure compressed gas is connected to the enclosure through an injection valve, and a discharge valve that communicates from the enclosure to water is provided. A pressure equalizing device for an underwater sound source device, comprising: a pressure controller that opens the injection valve when the pressure is lower than the hydraulic pressure and opens the discharge valve when the internal pressure of the enclosure is higher than the hydraulic pressure. 5. An oil chamber is formed between the diaphragm and the diaphragm by covering the underwater side with a flexible acoustically transparent film, and oil is sealed in the oil chamber. 4. A pressure equalizing device for an underwater sound source device according to 4. 6. The sub-oil chamber is formed between the enclosure and the diaphragm by partitioning the interior of the enclosure with a flexible blocking film facing the diaphragm, and the sub-oil chamber is filled with oil. The pressure equalizing device for an underwater sound source device according to claim 5. 7. The pressure equalizing device for an underwater sound source device according to claim 4, further comprising a check valve provided downstream of the discharge valve, the check valve being opened only when the upstream side has a high pressure. 8. The pressure equalizing device for an underwater sound source device according to claim 4, further comprising a gas permeable filter downstream of the release valve, the gas permeable filter transmitting gas and blocking water. 9. A cell having a gas introduction port and a liquid introduction port is divided into a gas chamber and a liquid chamber by a polymer continuous porous film that allows gas to pass therethrough and blocks water, and the polymer continuous pores. A gas permeation filter characterized in that a punching metal is superposed on the gas chamber side of a high quality film. 10. A filter element constituted by stacking a porous metal plate on one side of a polymer continuous porous film that allows gas to pass therethrough and blocks water in a housing having a gas inlet and a liquid inlet. Arranged in multiple stages so that the films and the metal plates face each other, the liquid flow path formed between the films is communicated with the liquid introduction port, and the gas flow path formed between the metal plates is the gas introduction port. A gas permeation filter characterized by being communicated with.