阅读说明：本技术 一种高稳定性水声标准器及制作方法 (High-stability underwater sound standard device and manufacturing method thereof ) 是由 何涛 赵涵 易文胜 于 2021-05-28 设计创作，主要内容包括：本发明公开了一种高稳定性水声标准器及制作方法。水声标准器主要由敏感元件组件、支撑杆、上下端盖、透声橡胶套、填充油、不锈钢压环、水密屏蔽电缆等构成。敏感元件选用多个小直径压电陶瓷圆管,谐振频率高于工作频率上限的2倍,远离谐振频率工作。压电陶瓷圆管通过软性的支撑垫柔性悬挂于支撑杆内部,保持自由振动状态。选用透声橡胶套作为透声窗,通过填充油传递能量,避免敏感元件与透声材料直接接触。在制作工艺方面,透声橡胶套与上下端盖通过不锈钢压环挤压变形密封,填充油充满后通过抽真空去除填充油内部气泡,该结构形式及制作工艺保证水声标准器具有良好温度压力时间稳定性,适合作为水声计量标准装置的考核标准。(The invention discloses a high-stability underwater sound standard device and a manufacturing method thereof. The underwater sound standard device mainly comprises a sensitive element assembly, a support rod, an upper end cover, a lower end cover, a sound-transmitting rubber sleeve, filling oil, a stainless steel pressure ring, a watertight shielding cable and the like. The sensitive element adopts a plurality of small-diameter piezoelectric ceramic round tubes, the resonant frequency is 2 times higher than the upper limit of the working frequency, and the piezoelectric ceramic round tubes work far away from the resonant frequency. The piezoelectric ceramic round tube is flexibly suspended inside the supporting rod through the soft supporting pad, and the free vibration state is kept. An acoustic-transmission rubber sleeve is selected as an acoustic-transmission window, energy is transmitted through filling oil, and the sensitive element is prevented from being in direct contact with an acoustic-transmission material. In the aspect of the manufacturing process, the sound-transmitting rubber sleeve and the upper end cover and the lower end cover are extruded and deformed to be sealed through the stainless steel compression ring, and air bubbles in the filling oil are removed through vacuumizing after the filling oil is filled.)

1. A high stability underwater sound etalon which is characterized in that: the acoustic transmission device comprises an upper end cover (4), a lower end cover (2), an acoustic transmission rubber sleeve (6) and a sensitive element assembly (1), wherein two ends of the acoustic transmission rubber sleeve (6) are respectively connected with the upper end cover (4) and the lower end cover (2) to form a closed space, and oil (5) is filled in the acoustic transmission rubber sleeve (6) to serve as a medium for energy transmission; a plurality of supporting rods (3) are arranged in the space and connected with the end faces of the upper end cover (4) and the lower end cover (2), a plurality of sensitive element assemblies (1) for receiving and transmitting sound waves are arranged up and down and flexibly hung on the supporting rods (3), and the positive and negative electrodes of the plurality of sensitive element assemblies (1) are connected in parallel through leads (7) and then connected to an electric connector (8); the watertight shielding cable (11) is connected with the electric connector (8), and the cable head (12) is arranged in the top cavity of the upper end cover (4) and is fixed through a fastening screw (13).

2. The high stability underwater acoustic etalon of claim 1, wherein: the sensitive element assembly (1) comprises an upper cover plate (14), a piezoelectric ceramic round tube (15), a supporting gasket (16) and a lower cover plate (17), wherein the piezoelectric ceramic round tube (15) is arranged between the upper cover plate (14) and the lower cover plate (17), and the supporting gasket (16) passes through the piezoelectric ceramic round tube (15) and is flexibly suspended on the supporting rod (3).

3. The high stability underwater acoustic etalon of claim 2, wherein: the inside of the piezoelectric ceramic round tube (15) is air decoupling, and the resonant frequency of the piezoelectric ceramic round tube is 2 times higher than the upper limit of the working frequency.

4. The high stability hydroacoustic etalon of claim 1 or 2, wherein: 8 sensitive element assemblies (1) are connected in parallel to form an equidistant linear array.

5. The high stability underwater acoustic etalon of claim 1, wherein: the acoustic impedance of the filling oil (5) should match that of water.

6. The high stability underwater acoustic etalon of claim 1, wherein: the sound-transmitting rubber sleeve (6) is sealed with the upper end cover (4) and the lower end cover (2) by extrusion deformation through the stainless steel pressure ring (9).

7. A method of making the high stability underwater acoustic etalon of claim 1 wherein: the method comprises the following steps:

1) a plurality of support rods (2) are arranged on an upper end cover (4), the assembled sensitive element assemblies (1) are sequentially arranged in the support rods (2) at equal intervals, and are fixed at corresponding positions by using glue, and the lower end cover (2) is covered;

2) the positive and negative electrodes of the sensitive element assemblies (1) are respectively connected together by using a lead (7) and finally connected with an electric connector (8);

3) the sound-transmitting rubber sleeve (6) penetrates through the lower end cover (2) to cover the outside of the support rod (3), one end of the sound-transmitting rubber sleeve is aligned with the step left by the upper end cover (4), and the other end of the sound-transmitting rubber sleeve is aligned with the step of the lower end cover (2); the stainless steel pressing ring (9) is arranged at the connecting position of the sound-transmitting rubber sleeve (6) and the end cover, and the stainless steel pressing ring (9) is extruded and deformed by buckling equipment to realize the sealing of the end cover and the rubber sleeve;

4) selecting proper filling oil (5) to be injected into the interior of the standard device through an oil filling hole in the upper end cover (4), vacuumizing the vacuum cavity after the standard device is filled with the filling oil, keeping the vacuum cavity for a certain time until all air bubbles in the standard device are discharged, screwing down an oil filling sealing screw 10, and realizing oil filling sealing by virtue of a sealing ring on the end surface of the oil filling sealing screw;

5) the watertight shielding cable (11) penetrates through the cable head (12), a certain length is reserved to strip the outer skin, the core wire is left, the watertight cable is vulcanized by using a mold, after the watertight shielding cable (11) is connected with the electric connector (8), the cable head (12) is installed into the top cavity of the upper end cover (4), and the underwater acoustic standard device is fixed by using the fastening screw (13), so that the underwater acoustic standard device is manufactured.

Technical Field

The invention relates to the field of underwater sound measurement, in particular to a standard device for examining an underwater sound measurement standard device, and mainly relates to a high-stability underwater sound standard device and a manufacturing method thereof.

Background

Before and after the second war, with the needs of military struggle and ocean development, the underwater acoustic engineering discipline is born. Through continuous development for decades, the application of the underwater acoustics engineering is more and more extensive nowadays, and the underwater acoustics engineering is integrated into various aspects of daily life, and the underwater acoustics engineering is mainly applied to military such as various sonar systems, torpedo sound guidance, torpedo sound fuzes, underwater sound countermeasure equipment and the like, and is mainly applied to civil such as marine communication, marine environment observation, oil and gas resource exploration, submarine submerged object search, fishery resource investigation and the like. In order to accurately evaluate whether the acoustic performance of the underwater acoustic equipment and an underwater acoustic system and components thereof meets the technical indexes and the use requirements of design, various underwater acoustic performance test systems need to be established, a plurality of sets of underwater acoustic measurement standard devices are established in a national defense technology industry underwater acoustic primary measurement station, the frequency range is from low frequency to high frequency, and the pressure is from normal pressure to high hydrostatic pressure. The underwater sound measurement standard device has small measurement uncertainty, and is a difficult work for judging whether the running condition is normal or not, and the operation is realized by using the device assessment standard. The standard for evaluating the receiving performance is generally called a standard hydrophone, the standard for evaluating the transmitting performance is called a standard transmitter, and the standard for evaluating the transmitting and receiving performance is called an underwater acoustic standard. The standard hydrophones are researched more, such as a "20 Hz-150 kHz high stability standard hydrophone" reported by Jia friend, Shen Xin and the like, and a "100 kHz-500 kHz piezoelectric composite material standard hydrophone" reported by He Tao, Xuzhuo and the like, but the standard hydrophones are usually provided with preamplifiers and can only be used for receiving performance evaluation and cannot be used for transmitting performance evaluation. Huaminglong et al propose '15 kHz-25 kHz underwater sound standard transmitting transducer' CN85200255, which is in a short cylindrical shape and has flat transmitting response in the working frequency range. As a common transmitting transducer, the transducer adopts PZT-4 material, the surface sealing material is sound-transmitting rubber, and the transducer works near the resonant frequency, so the performance of the transducer along with the change of temperature and pressure is far more than the measurement uncertainty of a standard device, and the transducer is not suitable as the transmitting evaluation standard of the standard device.

Disclosure of Invention

The invention aims to overcome the defects in the prior art and provides a high-stability underwater sound standard device and a manufacturing method thereof.

The invention discloses a high-stability underwater sound standard device structure and a manufacturing method thereof, wherein a plurality of small-diameter piezoelectric ceramic round tubes are used as sensitive elements, the sensitive elements are flexibly suspended, and oil is filled in the structure.

The object of the present invention is achieved by the following technical means. A high-stability underwater sound standard device comprises an upper end cover, a lower end cover, a sound-transmitting rubber sleeve and a sensitive element assembly, wherein two ends of the sound-transmitting rubber sleeve are respectively connected with the upper end cover and the lower end cover to form a closed space, and oil is filled in the sound-transmitting rubber sleeve to serve as a medium for energy transfer; the plurality of supporting rods are arranged in the space and connected with the end faces of the upper end cover and the lower end cover, a plurality of sensitive element assemblies for receiving and transmitting sound waves are arranged up and down and flexibly hung on the supporting rods, and the positive electrodes and the negative electrodes of the plurality of sensitive element assemblies are connected to the electric connector after being connected in parallel through leads; the watertight shielding cable is connected with the electric connector, and the cable head is arranged in the top cavity of the upper end cover and is fixed through the fastening screw.

The sensitive element assembly comprises an upper cover plate, a piezoelectric ceramic round tube, a supporting gasket and a lower cover plate, wherein the piezoelectric ceramic round tube is arranged between the upper cover plate and the lower cover plate, and the supporting gasket passes through the piezoelectric ceramic round tube and is flexibly suspended on the supporting rod.

The inside of the piezoelectric ceramic round tube is air decoupling, and the resonant frequency of the piezoelectric ceramic round tube is 2 times higher than the upper limit of the working frequency.

8 sensitive element assemblies are connected in parallel to form an equidistant linear array.

The acoustic impedance of the oil fill should match that of water.

The sound-transmitting rubber sleeve, the upper end cover and the lower end cover are sealed in a deformation mode through stainless steel pressure rings.

The invention also discloses a manufacturing method of the high-stability underwater sound standard device, which comprises the following steps:

1. mounting a plurality of support rods on an upper end cover, sequentially mounting the assembled sensitive element assemblies in the support rods, arranging the sensitive element assemblies at equal intervals, fixing the sensitive element assemblies at corresponding positions by using glue, and covering a lower end cover;

2. connecting the positive and negative electrodes of the multiple sensitive element assemblies together by using wires, and finally connecting the positive and negative electrodes with an electric connector;

3. the sound-transmitting rubber sleeve penetrates through the lower end cover to cover the outside of the support rod, one end of the sound-transmitting rubber sleeve is aligned with the step left by the upper end cover, and the other end of the sound-transmitting rubber sleeve is aligned with the step of the lower end cover; the stainless steel compression ring is arranged at the connecting position of the sound-transmitting rubber sleeve and the end cover, and the stainless steel compression ring is extruded and deformed by utilizing a buckling and pressing device, so that the end cover and the rubber sleeve are sealed;

4. selecting proper filling oil to be injected into the interior of the standard device through an oil filling hole in the upper end cover, vacuumizing the vacuum cavity after the filling oil is filled, keeping the vacuum cavity for a certain time until all bubbles in the interior of the standard device are discharged, screwing down an oil filling sealing screw, and realizing oil filling sealing by virtue of a sealing ring on the end surface of the oil filling sealing screw;

5. the watertight shielding cable penetrates through the cable head, a certain length is reserved for peeling off the outer skin, the core wire is left, the watertight is realized by utilizing the die vulcanization, after the watertight shielding cable is connected with the electric connector, the cable head is installed into the top cavity of the upper end cover, and the fastening screw 13 is utilized for fixing, so that the underwater acoustic standard device is manufactured.

The invention has the beneficial effects that:

a) the sensitive element adopts a small-diameter piezoelectric ceramic circular tube, the resonant frequency of the sensitive element is far higher than the upper limit of the working frequency during transmitting and receiving, the influence of the resonant frequency change caused by temperature, pressure and time change on the transmitting and receiving performance is small, and the underwater acoustic standard has high temperature pressure time stability.

b) The piezoelectric ceramic round tube is fixed inside the supporting gasket, and then the supporting rod is suspended flexibly, so that the rubber pad has a good decoupling effect, the free vibration state of the piezoelectric ceramic round tube is ensured, and the receiving sensitivity response flatness of the underwater acoustic standard device is improved.

c) The sound transmission rubber sleeve is adopted for sound transmission, filling oil with good stability is filled in the sound transmission rubber sleeve, the sound transmission material is not in direct contact with the piezoelectric ceramic round tube, the influence of the performance of the sound transmission material along with the change of temperature and pressure is greatly reduced, and the temperature and pressure stability of the standard device is further improved.

d) A plurality of piezoelectric ceramic round tubes are connected in parallel to form a linear array, so that the sending voltage response of the underwater acoustic standard device is greatly improved; after parallel connection, the static capacitance is increased, and the cable capacity of the standard device is improved.

Drawings

Fig. 1 is a schematic view of the general structure of the present invention.

Fig. 2 is a schematic view of a sensor assembly.

Reference numerals: the device comprises a sensitive element assembly 1, a lower end cover 2, a support rod 3, an upper end cover 4, filling oil 5, a sound-transmitting rubber sleeve 6, a lead 7, an electric connector 8, a stainless steel pressure ring 9, an oil-filling sealing screw 10, a watertight shielding cable 11, a cable head 12, a fastening screw 13, an upper cover plate 14, a piezoelectric ceramic round tube 15, a support gasket 16 and a lower cover plate 17.

Detailed Description

The invention will be described in detail with reference to the following figures and examples:

as shown in fig. 1, a high-stability underwater acoustic standard device mainly comprises a sensing element assembly 1, a lower end cover 2, a support rod 3, an upper end cover 4, filling oil 5, an acoustic rubber sleeve 6, a lead 7, an electric connector 8, a stainless steel pressure ring 9, an oil filling sealing screw 10, a watertight shielding cable 11, a cable head 12, a fastening screw 13 and the like. Two ends of the sound-transmitting rubber sleeve 6 are respectively connected with the upper end cover 4 and the lower end cover 2 to form a closed space, and oil 5 is filled in the sound-transmitting rubber sleeve 6 to serve as a medium for energy transmission; a plurality of support rods 3 are arranged in the space and connected with the end faces of the upper end cover 4 and the lower end cover 2, a plurality of sensitive element assemblies 1 for receiving and transmitting sound waves are arranged up and down and flexibly suspended on the support rods 3, and the positive and negative electrodes of the plurality of sensitive element assemblies 1 are connected in parallel through leads 7 and then connected to an electric connector 8; the watertight shielded cable 11 is connected with the electric connector 8, and the cable head 12 is installed in the top cavity of the upper end cover 4 and fixed by the fastening screw 13.

As shown in fig. 2, the sensor assembly, which is the core of the electro-acoustic conversion, converts the sensed acoustic signal into an electrical signal when the etalon is used for reception; when the etalon is used for transmission, the power amplifier excitation signal is applied to the sensor assembly to produce high frequency vibrations which transmit sound waves underwater. The sensitive element assembly 1 comprises an upper cover plate 14, a piezoelectric ceramic round tube 15, a supporting gasket 16 and a lower cover plate 17, wherein the piezoelectric ceramic round tube 15 is arranged between the upper cover plate 14 and the lower cover plate 17, and the supporting gasket 16 passes through the piezoelectric ceramic round tube 15 and is flexibly suspended on the supporting rod 3. The upper cover plate and the lower cover plate are used for sealing two end faces of the piezoelectric ceramic round tube, and an internal air layer is decoupled. The piezo ceramic cylinder is a small diameter cylinder that operates away from the resonant frequency, typically with an upper limit of the etalon operating frequency below 1/2 of the resonant frequency of the element. The supporting pad is made of rubber materials, a through hole with the same diameter as the piezoelectric ceramic round tube is reserved inside the supporting pad, the piezoelectric ceramic round tube is fixed inside the supporting pad and flexibly suspended inside the supporting rod, and the piezoelectric ceramic round tube is in a free vibration state. In implementation, the upper cover plate 14 and the lower cover plate 16 are respectively bonded to two end faces of the circular piezoelectric ceramic tube 15, the assembly body is installed inside the support gasket 16 after curing and molding, and the assembly body is fixed by glue, so that the sensitive element assembly is manufactured.

The lower end cover is made of copper or stainless steel materials with high density, and a through hole is reserved at the bottom of the lower end cover and used for hanging a balancing weight and keeping the standard device to be perpendicular to water when the standard device works. A step is reserved at the upper end of the lower end cover, the height of the step is equivalent to that of the sound-transmitting rubber sleeve, one end of the sound-transmitting sleeve is arranged at the step, and the stainless steel pressure ring is used for extrusion deformation to realize sealing between the end cover and the sound-transmitting rubber sleeve.

The support rod is a high-strength metal rod and is used for installing the sensitive element assembly and playing a role in protection. The diameter of the support rods is related to the highest working frequency, is generally less than 1/10 of the wavelength of the highest working frequency, and is far away from the piezoelectric ceramic round tube as far as possible.

The upper end cover is made of copper or stainless steel materials with high density, a step is reserved on the lower portion of the upper end cover, the height of the step is equal to that of the sound-transmitting rubber sleeve, one end of the sound-transmitting rubber sleeve is installed at the step, and the stainless steel pressure ring is used for extrusion deformation to seal the end cover and the sound-transmitting rubber sleeve. An electric connector is arranged in the upper end cover, and an oil-filled threaded through hole is reserved. The top cavity is closely matched with the cable head in size, and a radial O-shaped sealing ring on the cable head is used for realizing water tightness.

The filling oil is filling liquid between the sound-transmitting rubber sleeve and the piezoelectric ceramic round tube. The function of the device is to realize the energy transfer between the piezoelectric ceramic round tube and the sound-transmitting rubber sleeve. There are three requirements for the choice of oil extender material. First, acoustic properties, the acoustic impedance of the fill fluid should match that of water to avoid focusing or diverging of the sound waves. And secondly, the chemical property is stable, and the sound-transmitting rubber and the piezoelectric ceramic are not corrosive. And the viscosity is small in change along with temperature, and the liquid expansion coefficient is low. Silicone oils with good stability are generally selected.

The sound-transmitting rubber sleeve is vulcanized and formed by a mould, and the thickness is usually 3-5 mm. The sound-transmitting rubber sleeve needs to meet the requirements that sound waves incident on the material layer can pass through without reflection and loss, the characteristic impedance of the sound-transmitting rubber sleeve is matched with water, the attenuation constant is very low, the sound-transmitting rubber sleeve has low water permeability, and the sound-transmitting rubber sleeve can work underwater for a long time and is usually made of chloroprene rubber or butyl rubber.

The lead wires are used for electrical connection among the 8 sensitive element assemblies and connection between the sensitive element assemblies and the cable connector. The etalon needs to be used for transmission and the wires should meet the current-voltage requirements for transmission.

The electric connector is used for electrically connecting the oil filling part of the standard device with the rear end, a 2-core small-size electric connector is selected, one end of the electric connector is connected with the anode and the cathode of the piezoelectric ceramic circular tube, and the other end of the electric connector is connected with a core wire of the watertight shielding cable.

The stainless steel pressure ring is mainly used for sealing between the sound-transmitting rubber sleeve and the end cover. Before the rubber sleeve is not deformed, the inner diameter of the rubber sleeve is the same as the outer diameter of the rubber sleeve, and the rubber sleeve is extruded and deformed by utilizing a buckling and pressing device, so that the rubber sleeve is deformed, and the watertight between the rubber sleeve and the end cover is realized.

The watertight shielding cable transmits the electric signal converted by the piezoelectric ceramic round tube to the signal acquisition end during receiving, and applies an excitation signal to the piezoelectric ceramic round tube from the power amplifier end during transmitting. And a watertight cable with a shield is selected. The metal shielding layer is used for shielding electromagnetic signals in the space and reducing electromagnetic interference.

The specific manufacturing method comprises the following steps:

1. installing 6 support rods 2 on an upper end cover 4, sequentially installing the assembled sensitive element assemblies 1 in the support rods 2, arranging the sensitive element assemblies at equal intervals, fixing the sensitive element assemblies at corresponding positions by using glue, and covering the lower end cover 2;

2. the positive and negative electrodes of the 8 sensitive element assemblies 1 are respectively connected together by using a lead 7 and finally connected with an electric connector 8;

3. the sound-transmitting rubber sleeve 6 penetrates through the lower end cover 2 to cover the outside of the support rod 3, one end of the sound-transmitting rubber sleeve is aligned with the step left by the upper end cover 4, and the other end of the sound-transmitting rubber sleeve is aligned with the step of the lower end cover 2; the stainless steel pressing ring 9 is arranged at the connecting position of the sound-transmitting rubber sleeve 6 and the end cover, and the stainless steel pressing ring 9 is extruded and deformed by a buckling and pressing device to realize the sealing of the end cover and the rubber sleeve;

4. selecting proper filling oil 5 to be injected into the interior of the standard device through an oil filling hole in the upper end cover 4, vacuumizing the vacuum cavity after the filling, keeping the vacuum cavity for a certain time until all bubbles in the interior of the standard device are discharged, screwing an oil filling sealing screw 10, and realizing oil filling sealing by virtue of a sealing ring on the end face of the oil filling sealing screw;

5. the watertight shielding cable 11 penetrates through the cable head 12, a certain length is reserved for peeling off the outer skin, a core wire is left, the watertight shielding cable 11 is vulcanized by using a mold to realize watertight shielding, after the watertight shielding cable 11 is connected with the electric connector 8, the cable head 12 is installed into a cavity at the top of the upper end cover 4, and the fastening screw 13 is used for fixing, so that the underwater sound standard device is manufactured.

The invention selects the sound-transmitting rubber sleeve as the sound-transmitting window, and energy is transmitted by filling oil, so that the sensitive element is prevented from directly contacting with the sound-transmitting material. In the aspect of the manufacturing process, the sound-transmitting rubber sleeve and the upper end cover and the lower end cover are extruded and deformed to be sealed through the stainless steel compression ring, and air bubbles in the filling oil are removed through vacuumizing after the filling oil is filled.

It should be understood that equivalent substitutions and changes to the technical solution and the inventive concept of the present invention should be made by those skilled in the art to the protection scope of the appended claims.