CN105689248A - Cross-shaped orthogonal compound drive piezoelectric pipe-shaped transducer - Google Patents

Abstract

The invention provides a cross-shaped orthogonal compound-driven piezoelectric tubular transducer, which relates to the field of ultrasonic transducers and includes a radial radiation shell, a conical prestressed elastic expansion structure, and a cross-shaped orthogonal compound central mass block , four groups of piezoelectric ceramic crystal stacks and four outer mass blocks; the mass block includes four components; the inner surface of the component parts is surrounded by a cylindrical hole and two conical holes; the expansion structure includes a fixing device and two conical holes Expansion body; the expansion body is inserted into the tapered hole; the piezoelectric ceramic crystal stack is formed by stacking electrode sheets and even-numbered piezoelectric ceramic wafers. The electrode piece is in contact with the inner end surface of the outer mass block; the other ends of the four outer mass blocks are in contact with the inner wall of the radial radiation shell. The application solves the technical problem that the ultrasonic transducer in the prior art has a sound field "blind zone" and "standing wave characteristics", and the radial ultrasonic radiation intensity is relatively weak.

Description

Cross Orthogonal Composite Driving Piezoelectric Tube Transducer

technical field

The invention relates to the field of ultrasonic transducers, in particular to a cross-shaped orthogonal compound-driven piezoelectric tubular transducer.

Background technique

The function of the ultrasonic transducer is to convert the input electrical power into mechanical power (that is, ultrasonic waves) and then transmit it out, while consuming a small part of the power itself.

In the field of power ultrasonic and underwater acoustic technology, the sandwich longitudinal vibration piezoelectric ultrasonic transducer is the most widely used. The transducer was invented by French scientist Lang Zhiwan, and has the advantages of simple structure, large power capacity and high electromechanical conversion efficiency. With the development of science and technology and the wide application of ultrasonic technology, ultrasound has gained important applications in many new technology fields (such as ultrasonic Chinese herbal medicine extraction, ultrasonic sewage treatment, ultrasonic oil recovery and ultrasonic chemical reaction, etc.).

In these new technology fields, higher requirements are put forward for the radiation power and the range of sound waves of ultrasonic transducers: high power, high efficiency and omnidirectional ultrasonic radiation. For the existing sandwich-type longitudinal vibration piezoelectric ultrasonic transducer, due to its own theoretical and structural limitations, a single sandwich-type longitudinal vibration piezoelectric ultrasonic transducer has limited power capacity, single ultrasonic action direction, and ultrasonic radiation area. Therefore, it is difficult to meet the characteristics of high-power, omni-directional ultrasonic radiation required in new ultrasonic technology. At present, in order to improve the shortcomings of a single sandwich longitudinal vibration piezoelectric ultrasonic transducer, the following types of ultrasonic transducers have been developed.

(1) Array ultrasonic transducer. An array sound source is formed by bonding one or more rows of sandwich-type longitudinal vibration piezoelectric ultrasonic transducers at the bottom or around the container to radiate sound waves into the liquid. Although the array sound source can solve the shortcomings of a single sandwich transducer such as limited ultrasonic action area and power and single sound radiation direction, but because the radiation surface of the vibrator of the longitudinal transducer is a plane, its radiation sound field has strong directivity , there is usually a "blind zone" in the sound field, which is also the "bottleneck" that restricts the performance of this type of transducer for liquid ultrasonic treatment.

(2) push-pull transducer. Its working principle is that through the longitudinal vibration of two sandwich-type longitudinal piezoelectric transducers coupled at both ends of a metal circular tube, it produces a longitudinal push-pull effect on the circular tube and generates sound energy radiation in the radial direction of the circular tube. From the perspective of the geometric dimensions and acoustic radiation characteristics of the push-pull transducer, the vibration of this type of transducer belongs to the high-order longitudinal vibration of the metal circular tube excited by the longitudinal vibration of the sandwich longitudinal piezoelectric transducer. The radially coupled vibration is generated due to the Poisson effect in the high-order longitudinal vibration mode. Therefore, although this type of transducer can solve the shortcomings of a single sandwich-type longitudinal vibration piezoelectric ultrasonic transducer, such as a single direction of ultrasonic action and limited ultrasonic radiation area, but because the main force of the system when this type of transducer is working The vibration direction is still in the longitudinal direction, and there are disadvantages that the radial coupling vibration generated by the Poisson effect is relatively weak and the radial ultrasonic radiation intensity is also weak. In addition, since the metal circular tube works in a high-order longitudinal vibration mode, its radiated sound field has obvious "standing wave characteristics" along the longitudinal direction.

Based on this, the present invention provides a cross-shaped orthogonal compound-driven piezoelectric tubular transducer to solve the above-mentioned technical problems.

Contents of the invention

The purpose of the present invention is to provide a cross-shaped orthogonal composite drive piezoelectric tubular transducer to solve the "blind area" of the sound field in the array ultrasonic transducer in the prior art, while the push-pull transducer radially The ultrasonic radiation intensity is weak, and the radiation sound field has obvious "standing wave characteristics" along the longitudinal direction.

In an embodiment of the present invention, a cross-shaped orthogonal compound-driven piezoelectric tubular transducer is provided, and the cross-shaped orthogonal compound-driven piezoelectric tubular transducer includes a cross-shaped orthogonal compound sandwich piezoelectric excitation A source and a cylindrical radial radiation shell; the radial radiation shell is set outside the cross-orthogonal composite sandwich piezoelectric excitation source;

The cross-orthogonal composite sandwich-type piezoelectric excitation source includes a conical prestressed elastic expansion structure, a cross-shaped orthogonal composite central mass, four groups of piezoelectric ceramic crystal stacks with the same structure, and four outer masses with the same shape;

The cross-shaped orthogonal composite central mass includes four components with the same shape, and the four components are placed symmetrically in the center; four groups of piezoelectric ceramic crystal stacks surround the cross-shaped orthogonal composite central mass. The central axis is symmetrically placed; the four outer masses are symmetrically placed around the central axis of the cross-shaped orthogonal composite central mass;

The inner surfaces of the four components enclose a cylindrical hole and two identical tapered holes; the small ends of the two tapered holes communicate with the cylindrical hole respectively;

The conical prestressed elastic expansion structure includes a fixing device and two conical expansion bodies of the same shape; the two conical expansion bodies are respectively fixed and inserted in the two conical holes through the fixing device;

Each group of piezoelectric ceramic crystal stacks is formed by stacking an even number of piezoelectric ceramic wafers with the same shape, and metal electrode sheets are installed between two adjacent piezoelectric ceramic wafers. The outer sides of the piezoelectric ceramic wafers are also respectively equipped with the metal electrode sheets; the adjacent electrode sheets are connected to electrodes with opposite polarities;

The outer surfaces of the four components are all planes, and the inner end surfaces of the four outer masses are all planes; the electrode piece at one end of each piezoelectric ceramic stack is connected to one of the components. The outer surface abuts, and the electrode sheet at the other end abuts against the inner end surface of one of the outer masses;

The other ends of the four outer masses abut against the inner wall of the radial radiation shell.

Optionally, the fixing device is a prestressed bolt, the prestressed bolt includes a double-ended screw and two nuts, and the double-ended screw is inserted into the cylindrical hole;

The two conical expansion bodies are respectively provided with central holes, and the two conical expansion bodies are respectively sleeved on the double-ended screws through the central holes;

The two nuts are respectively screwed to the two ends of the double-ended screw.

Optionally, the four components are sequentially connected by four identical connecting pieces, and the four connecting pieces are placed symmetrically about the center.

Optionally, the cross-shaped orthogonal composite central mass is integrally formed.

Optionally, the piezoelectric ceramic wafer is circular.

Optionally, the electrode sheet includes an electrode part and a connection part, the connection part is fixedly connected to the electrode part, and the connection part is used to connect to a power supply; the electrode part is the shape of the piezoelectric ceramic wafer In the same circular shape, the electrode part overlaps with the piezoelectric ceramic wafer.

Optionally, the four outer masses are integrally formed with the radial radiation shell.

Optionally, waterproof sealing covers are fixedly connected to both ends of the radial radiation casing.

Optionally, the two waterproof sealing covers are connected to the radial radiation casing by screws.

Optionally, sealing rings are respectively provided between the two waterproof sealing covers and the radial radiation casing.

The cross-shaped orthogonal compound-driven piezoelectric tubular transducer provided by the present invention is divided into two types according to its vibration mode: one is a forced vibration compound type; the other is a same-frequency resonance compound type.

For the forced vibration composite type, its working principle is that the cross-shaped orthogonal composite sandwich piezoelectric excitation source inside the transducer is designed to work in the orthogonal longitudinal resonance mode, turn on the power supply, adjust the frequency and matching conditions of the power supply, when When the excitation frequency of the power supply is consistent with the longitudinal resonance frequency of the corresponding order of the cross-shaped orthogonal composite sandwich piezoelectric excitation source inside the transducer, the cross-shaped orthogonal composite sandwich piezoelectric excitation source will act along its orthogonal direction. The alternating longitudinal vibration of expansion and contraction directly drives the radial radiation shell to perform forced composite vibration, thereby radiating sound waves to the radial direction of the radiation shell.

For the same-frequency resonance composite type, its working principle is that the orthogonal longitudinal resonance frequency of the cross-shaped orthogonal composite sandwich piezoelectric excitation source inside the transducer is designed to be the same as the radial resonance frequency of its external radiation shell. Turn on the power supply, adjust the frequency and matching conditions of the power supply, when the excitation frequency of the power supply is consistent with the longitudinal resonance frequency of the cross-shaped orthogonal composite sandwich piezoelectric excitation source inside the transducer and the radial resonance frequency of the external radiation shell At this time, the longitudinal vibration of the internal cross-shaped orthogonal compound sandwich piezoelectric excitation source excites the radial vibration of the outer radiation shell along the radial direction of the radiation shell, so as to realize the longitudinal composite same-frequency resonance between the inner and outer parts And radiate sound waves radially to the radiation shell.

Piezoelectric ceramics have the following characteristics: When voltage is applied to piezoelectric ceramics, mechanical deformation will occur with changes in voltage and frequency. On the other hand, when the piezoelectric ceramic is deformed by an external force, positive and negative charges are generated on its two opposite electrode surfaces. Using this principle, piezoelectric ceramics can be used as ultrasonic transducers. The cross-shaped orthogonal composite driving piezoelectric tubular transducer provided by the present invention utilizes the characteristics of piezoelectric ceramics to generate ultrasonic waves. Inserting the conical expansion body into the conical hole makes the four central components expand outwards, giving the piezoelectric ceramic wafer an outward prestress. The four external mass blocks located on the outside give an inward prestress to the piezoelectric ceramic wafer under the action of the radial radiation shell. The radial radiation shell is made of metal material with high rigidity and can provide sufficient prestress. stress. This is equivalent to forming a cross-orthogonal compound similar to the traditional two groups of sandwich piezoelectric transducers. The depth of insertion of the tapered expansion body determines the size of the prestress. Excessive prestress causes the piezoceramic wafer to be pressed too tightly, thereby dampening its vibration. If the prestress is too small, the piezoelectric ceramic chip will be pressed too loosely, and if the gap is too large, it will be easily shattered. Therefore, a suitable prestress range is required, that is, a suitable insertion depth. This insertion depth is determined by mathematical calculations and experiments during design. This application realizes adjustable prestress through different insertion depths, which is suitable for different situations and can be adjusted to a suitable prestress.

The cross-shaped orthogonal composite drive piezoelectric tubular transducer provided by the present invention has a centrally symmetrical overall structure, radiates ultrasonic waves to the surroundings very uniformly, and does not have a "blind area" in the sound field. Ultrasonic waves are generated by four groups of piezoelectric ceramic crystal piles , using the longitudinal vibration of the piezoelectric ceramic stack to drive the radial vibration of the tube-shaped radial radiation shell. Adopting the advantages of simple structure and large power capacity of the traditional sandwich piezoelectric transducer, the purpose of improving the structure of the existing radial composite tubular transducer and increasing its power capacity is achieved, and the radial ultrasonic radiation intensity is relatively strong , there is no longitudinal "standing wave characteristic".

The conical prestressed elastic expansion structure is used to cooperate with the external tubular shell to apply internal and external bidirectional prestress to the four sets of piezoelectric ceramic crystal stacks inside, which greatly improves the power density of the tubular transducer. At the same time, the expansion prestressing mechanism also enhances the radial stiffness of the orthogonal compound driven piezoelectric tubular transducer. Setting the outer mass block on the outside gives the piezoelectric ceramic chip an inward prestress, which has a better fixing effect, improves the stiffness of the entire device, and further improves the overall vibration performance of the entire transducer. It can also be used in high-pressure environments, such as deep well oil production acoustic emission transducers, underwater acoustic emission transducers in deep sea, etc., expanding its application range. In addition, since the prestress of the internal piezoelectric ceramic crystal stack of the present application is applied by the conical prestress elastic expansion structure in conjunction with the external tubular shell, the central prestress of the traditional sandwich piezoelectric transducer is omitted Bolts, so the piezoelectric crystal stack can replace the piezoelectric ring used in the traditional sandwich piezoelectric transducer with a whole piece of piezoelectric ceramic wafer. Therefore, the piezoelectric ceramic crystal stack that the present application adopts piezoelectric ceramic wafer to form has larger volume than the piezoelectric ceramic crystal stack that the traditional sandwich-type piezoelectric transducer is formed by circular piezoelectric ceramic wafer, thereby further increases The power capacity of the transducer is increased. The greater the power, the stronger the radial ultrasonic radiation intensity, and there is no longitudinal "standing wave characteristic".

Based on this, the application uses the longitudinal vibration of the piezoelectric ceramic crystal pile to drive the radial vibration of the tubular radial radiation shell, so as to realize the high-power operation of the transducer and the radial omni-directional sound wave radiation, and there is no "blind area" of the sound field and longitudinal "standing wave characteristics". This application has the advantages of high power, high efficiency, radial and omni-directional sound wave radiation and adjustable prestress of the transducer, etc., and can be widely used in ultrasonic oil recovery, underwater acoustic emission transducers, ultrasonic cleaning, ultrasonic extraction, ultrasonic emulsification, Ultrasonic pulverization and sonochemical liquid treatment and other technical fields.

Description of drawings

In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the accompanying drawings that need to be used in the description of the specific embodiments or prior art. Obviously, the accompanying drawings in the following description The drawings show some implementations of the present invention, and those skilled in the art can obtain other drawings based on these drawings without any creative work.

Fig. 1 is the structural representation of embodiment cross-shaped orthogonal composite driving piezoelectric tubular transducer;

Fig. 2 is the sectional view of embodiment cross-shaped orthogonal composite driving piezoelectric tubular transducer;

Fig. 3 is the schematic structural diagram of the cross-orthogonal compound sandwich type piezoelectric excitation source of the embodiment;

Fig. 4 is the explosion schematic diagram of embodiment prestressed bolt and cross-shaped orthogonal compound central mass matching;

Fig. 5 is a top view of a cross-shaped orthogonal composite central mass;

Fig. 6 is an A-direction cross-sectional view of a cross-shaped orthogonal composite central mass;

Fig. 7 is the structural representation of embodiment piezoelectric ceramic crystal pile;

Fig. 8 is a front view of the piezoelectric ceramic crystal stack of the embodiment.

Reference signs:

1-radial radial shell; 2-conical prestressed elastic expansion structure; 3-cross-shaped orthogonal composite central mass;

4-Piezoelectric ceramic crystal pile; 5-External mass block; 6-Cylindrical hole;

7-tapered hole; 8-tapered expansion body; 9-double-ended screw;

10-nut; 11-central hole; 12-piezoelectric ceramic chip;

13-electrode sheet; 14-waterproof sealing cover; 31-component.

detailed description

The technical solutions of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Apparently, the described embodiments are some of the embodiments of the present invention, but not all of them. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" etc. The indicated orientation or positional relationship is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the referred device or element must have a specific orientation, or in a specific orientation. construction and operation, therefore, should not be construed as limiting the invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and should not be construed as indicating or implying relative importance.

In the description of the present invention, it should be noted that unless otherwise specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection or a detachable connection. Connection, or integral connection; it can be mechanical connection or electric welding connection; it can be direct connection or indirect connection through an intermediary, and it can be the internal communication of two components. Those of ordinary skill in the art can understand the specific meanings of the above terms in the present invention in specific situations.

Embodiment one

As shown in Figures 1-8, a cross-shaped orthogonal compound-driven piezoelectric tubular transducer is provided in this embodiment, and the cross-shaped orthogonal compound-driven piezoelectric tubular transducer includes a cross-orthogonal A composite sandwich piezoelectric excitation source and a cylindrical radial radiation casing 1; the radial radiation casing 1 is set outside the cross-orthogonal composite sandwich piezoelectric excitation source;

The cross-orthogonal composite sandwich piezoelectric excitation source includes a conical prestressed elastic expansion structure 2, a cross-shaped orthogonal composite central mass 3, four groups of piezoelectric ceramic crystal stacks 4 with the same structure and four outer shells with the same shape. mass block 5;

The cross-shaped orthogonal composite central mass 3 includes four components 31 of the same shape, and the four components 31 are placed symmetrically in the center; four groups of piezoelectric ceramic crystal stacks 4 surround the cross-shaped orthogonal composite The central axis of the central mass 3 is symmetrically placed; the four outer masses 5 are symmetrically placed around the central axis of the cross-shaped orthogonal composite central mass 3;

The inner surfaces of the four components 31 enclose a cylindrical hole 6 and two identical tapered holes 7; the small ends of the two tapered holes 7 communicate with the cylindrical hole 6 respectively;

The conical prestressed elastic expansion structure 2 includes a fixing device and two conical expansion bodies 8 of the same shape; the two conical expansion bodies 8 are respectively fixed and inserted in the two conical expansion bodies through the fixing device. Inside hole 7;

Each group of piezoelectric ceramic crystal stacks 4 is formed by stacking piezoelectric ceramic wafers 12 of the same shape in an even number, and metal electrode sheets 13 are installed between adjacent two piezoelectric ceramic wafers 12, located at The outer sides of the piezoelectric ceramic wafers 12 at both ends are also respectively equipped with the metal electrode sheets 13; the adjacent electrode sheets 13 are connected to electrodes with opposite polarities; in this embodiment, each group of piezoelectric ceramic crystal stacks 4 includes four disc-shaped piezoelectric ceramic wafers, which are respectively marked as 12a, 12b, 12c and 12d in the figure for the convenience of understanding. Between two adjacent piezoelectric ceramic wafers and on the outside of the piezoelectric ceramic wafers 12a and 12d are respectively installed electrode sheets, which are respectively marked as 13a, 13b, 13c, 13d and 13e in the figure for the convenience of description. The electrode pieces 13a, 13c and 13e are connected to the negative pole of the power supply, and the electrode pieces 13b and 13d are connected to the positive pole of the power supply.

The outer surfaces of the four component parts 31 are all planes, and the inner end surfaces of the four outer mass blocks 5 are all planes; the electrode sheets (13a) at one end of each piezoelectric ceramic crystal stack are connected with one of them The outer surface of the component part 31 abuts, and the electrode piece (13e) at the other end abuts against the inner end surface of one of the outer masses 5;

The other ends of the four outer masses 5 abut against the inner wall of the radially radiating shell 1 .

The cross-shaped orthogonal compound-driven piezoelectric tubular transducer provided by the present invention is divided into two types according to its vibration mode: one is a forced vibration compound type; the other is a same-frequency resonance compound type.

For the forced vibration composite type, its working principle is that the cross-shaped orthogonal composite sandwich piezoelectric excitation source inside the transducer is designed to work in the orthogonal longitudinal resonance mode, turn on the power supply, adjust the frequency and matching conditions of the power supply, when When the excitation frequency of the power supply is consistent with the longitudinal resonance frequency of the corresponding order of the cross-shaped orthogonal composite sandwich piezoelectric excitation source inside the transducer, the cross-shaped orthogonal composite sandwich piezoelectric excitation source will act along its orthogonal direction. The alternating longitudinal vibration of expansion and contraction directly drives the radial radiation shell 1 to perform forced composite vibration, thereby radiating sound waves to the radial direction of the radiation shell.

For the same-frequency resonance composite type, its working principle is that the orthogonal longitudinal resonance frequency of the cross-shaped orthogonal composite sandwich piezoelectric excitation source inside the transducer is designed to be the same as the radial resonance frequency of its external radiation shell. Turn on the power supply, adjust the frequency and matching conditions of the power supply, when the excitation frequency of the power supply is consistent with the longitudinal resonance frequency of the cross-shaped orthogonal composite sandwich piezoelectric excitation source inside the transducer and the radial resonance frequency of the external radiation shell At this time, the longitudinal vibration of the internal cross-shaped orthogonal compound sandwich piezoelectric excitation source excites the radial vibration of the outer radiation shell along the radial direction of the radiation shell, so as to realize the longitudinal composite same-frequency resonance between the inner and outer parts And radiate sound waves radially to the radiation shell.

The cross-shaped orthogonal composite driving piezoelectric tubular transducer provided by the present invention utilizes the characteristics of piezoelectric ceramics to generate ultrasonic waves. Inserting the conical expansion body 8 into the conical hole 7 causes the four central components 31 to expand outward, giving the piezoelectric ceramic wafer 12 an outward prestress. The four outer masses 5 located on the outside give an inward prestress to the piezoelectric ceramic wafer 12 under the action of the radially radiating shell 1 . This is equivalent to forming a cross-orthogonal compound similar to the traditional two groups of sandwich piezoelectric transducers. The insertion depth of the conical expansion body 8 determines the size of the prestress. Excessive prestress makes the piezoelectric ceramic wafer 12 pressed too tightly, thereby suppressing its vibration. If the prestress is too small, the piezoelectric ceramic chip 12 is easily pressed too loosely, and the gap is too large, which is easy to be shattered. Therefore, a suitable prestress range is required, that is, a suitable insertion depth. This insertion depth is determined by mathematical calculations and experiments during design. This application realizes adjustable prestress through different insertion depths, which is suitable for different situations and can be adjusted to a suitable prestress.

The cross-shaped orthogonal compound-driven piezoelectric tubular transducer provided by the present invention has a centrally symmetrical overall structure, radiates ultrasonic waves to the surroundings very uniformly, and has no "blind area" in the sound field. Ultrasonic waves are generated by four groups of piezoelectric ceramic crystal stacks 4 , and the radial vibration of the tubular radial radiation shell 1 is driven by the longitudinal vibration of the piezoelectric ceramic crystal stacks 4 . Utilizing the advantages of simple structure and large power capacity of the traditional sandwich piezoelectric transducer, the purpose of improving the structure of the existing radial composite tubular transducer and increasing its power capacity is achieved. In this application, the radial ultrasonic radiation intensity is relatively strong, and there is no longitudinal "standing wave characteristic".

The conical prestressed elastic expansion structure 2 is adopted, and the external tubular shell is used to apply internal and external bidirectional prestress to the internal four sets of piezoelectric ceramic crystal piles 4, which greatly improves the power density of the tubular transducer. At the same time, the expansion type prestressing mechanism also enhances the radial stiffness of the orthogonal compound driven piezoelectric tubular transducer, and the external mass 5 is arranged to give the piezoelectric ceramic wafer 12 prestress, the fixing effect is relatively good, and the The stiffness of the entire device is improved, thereby improving the overall vibration performance of the entire transducer. It can also be used in high-pressure environments, such as deep well oil production acoustic emission transducers, underwater acoustic emission transducers in deep sea, etc., expanding its application range. In addition, since the prestress of the internal piezoelectric ceramic crystal stack 4 of the present application is applied by the conical prestressed elastic expansion structure 2 in coordination with the external tubular shell, the center of the traditional sandwich piezoelectric transducer is omitted. Prestressed bolts, so the piezoelectric crystal stack can use a whole piece of piezoelectric ceramic wafer 12 to replace the piezoelectric ring used in the traditional sandwich piezoelectric transducer. Therefore, the piezoelectric ceramic crystal stack 4 composed of ceramic wafers used in the present application has a larger volume than the piezoelectric ceramic crystal stack 4 composed of annular piezoelectric ceramic wafers in the traditional sandwich piezoelectric transducer, thereby further increasing the the power capacity of the transducer. The greater the power, the stronger the radial ultrasonic radiation intensity, and there is no longitudinal "standing wave characteristic".

Based on this, the present application uses the longitudinal vibration of the piezoelectric ceramic crystal pile 4 to drive the radial vibration of the tubular radial radiation shell 1, so as to realize the high-power operation of the transducer and the radial omni-directional sound wave radiation without the existence of a sound field " dead zone" and longitudinal "standing wave characteristics". This application has the advantages of high power, high efficiency, radial and omnidirectional emission of sound waves, and adjustable prestress of the transducer, and can be widely used in ultrasonic oil recovery, underwater acoustic emission transducers, ultrasonic cleaning, ultrasonic extraction, ultrasonic emulsification, Ultrasonic pulverization and sonochemical liquid treatment and other technical fields.

As shown in Figures 1-6, in the optional solution of this embodiment, the fixing device is a prestressed bolt, and the prestressed bolt includes a double-ended screw 9 and two nuts 10, and the double-ended screw 9 is inserted into the Inside the cylindrical hole 6;

The two conical expansion bodies 8 are respectively provided with central holes 11, and the two conical expansion bodies 8 are respectively fitted on the double-ended screws 9 through the central holes 11;

The two nuts 10 are respectively screwed to the two ends of the double-ended screw 9 .

In this way, by rotating the two nuts 10 at both ends clockwise and counterclockwise, the depth at which the two conical expansion bodies 8 are inserted into the two conical holes 7 is adjusted, thereby adjusting the pressure of each group. The prestressed electroceramic crystal stack 4 is simple in structure and convenient to adjust.

In an optional solution of this embodiment, the four components 31 are sequentially connected by four identical connecting pieces, and the four connecting pieces are placed symmetrically about the center.

The four component parts 31 are connected together to facilitate assembly, which is more convenient than the assembly of four separately existing component parts 31.

Further, the cross-shaped orthogonal composite central mass 3 is integrally formed.

The cross-shaped orthogonal composite central mass 3 is integrally formed, and four U-shaped slits are cut in the center, so that the four component parts 31 are connected by wires, which is easy to assemble and process.

As shown in Figures 7 and 8, in an alternative solution of this embodiment, the piezoelectric ceramic wafer 12 is circular.

The circular piezoelectric ceramic wafer 12 is easy to process, and compared with traditional sandwich piezoelectric transducers, it does not need to be fixed with central prestressing bolts. In the case of the same outer diameter, the present application adopts a piezoelectric crystal stack 4 composed of disc-shaped piezoelectric ceramic wafers, which has a higher Larger volume, thus further increasing the power capacity of the transducer.

Further, the electrode sheet 13 includes an electrode part and a connection part, the connection part is fixedly connected to the electrode part, and the connection part is used to connect to a power supply; the electrode part is connected to the piezoelectric ceramic wafer 12 The shape is circular with the same shape, and the electrode part overlaps with the piezoelectric ceramic wafer 12 .

Such arrangement makes the piezoelectric ceramic chip 12 and the electrode sheet 13 laminated together, avoiding strong vibrations that easily cause high-voltage ignition and electrode shedding when the input power of the transducer is large.

In an optional solution of this embodiment, the four outer masses 5 are integrally formed with the radial radiation shell 1 .

The purpose is to avoid the contact surface formed between the cross-shaped orthogonal composite sandwich piezoelectric excitation source and the radial radiation shell 1, and effectively avoid the transmission loss of ultrasonic energy between the contact surfaces.

As shown in FIG. 1 , in an alternative solution of this embodiment, waterproof sealing covers 14 are fixedly connected to both ends of the radial radiation housing 1 .

Prevent dust, moisture, etc. from entering, causing short circuits, etc.

Further, the two waterproof sealing covers 14 are connected to the radial radiation casing 1 by screws.

The way of screw connection is relatively simple and convenient to process.

Further, sealing rings are respectively provided between the two waterproof sealing covers and the radial radiation housing 1 .

The sealing characteristics are further improved to prevent the ingress of dust and moisture.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present invention, rather than limiting them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: It is still possible to modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the technical solutions of the various embodiments of the present invention. scope.

Claims (10)

1. the cross orthogonal composite flooding tubular transducer of piezoelectricity, it is characterised in that include cross orthogonal composite sandwich formula piezoelectric excitation source and cylindric radial radiation housing；Described radial radiation housing is sleeved on outside described cross orthogonal composite sandwich formula piezoelectric excitation source；

Described cross orthogonal composite sandwich formula piezoelectric excitation source includes taper prestressing force elastic expansion structure, cross orthogonal complex centre mass, outer mass that piezoelectric ceramics crystalline substance heap that four groups of structures are identical is identical with four shapes；

Described cross orthogonal complex centre mass includes four block-shaped identical composition portions, and four pieces of described composition portion centrosymmetry are placed；Described in four groups, piezoelectric ceramics crystalline substance heap is placed around the central shaft centrosymmetry of described cross orthogonal complex centre mass；Four described outer masses are placed around the central shaft centrosymmetry of described cross orthogonal complex centre mass；

The medial surface in four described composition portions surrounds a cylindrical hole and two identical bellmouths；The small end of two described bellmouths is through with described cylindrical hole respectively；

Described taper prestressing force elastic expansion structure includes fixing device and the identical expansion cone of two shapes；Two described expansion cone are inserted in two described bellmouths by described fixing device is fixing respectively；

Often organize described piezoelectric ceramics crystalline substance heap to stack together by the piezoelectric ceramic wafer that even slice shape is identical, being mounted on metal electrode film between piezoelectric ceramic wafer described in adjacent two panels, the outside of the described piezoelectric ceramic wafer being positioned at two ends is also separately installed with described metal electrode film；Adjacent described electrode slice connects opposite polarity electrode；

The lateral surface in four described composition portions is plane, and the inner face of four described outer masses is plane；The lateral surface of described electrode slice and one of described composition portion that each described piezoelectric ceramics crystalline substance piles one end abuts, and the inner face of the described electrode slice mass outer with one of them described of the other end abuts；

The other end of four described outer masses abuts with the inwall of described radial radiation housing。

2. the tubular transducer of cross according to claim 1 orthogonal composite flooding piezoelectricity, it is characterised in that described fixing device is pre-stressed bolt, described pre-stressed bolt includes double threaded screw and two nuts, and described double threaded screw is inserted in described cylindrical hole；

Two described expansion cone are respectively arranged with centre bore, and two described expansion cone are set on described double threaded screw by described centre bore；

Two described nuts are spirally connected with the two ends of described double threaded screw respectively。

3. the tubular transducer of cross according to claim 1 orthogonal composite flooding piezoelectricity, it is characterised in that four pieces of described composition portions are sequentially connected with by four identical connectors, four described connectors are centrosymmetric placement。

4. the tubular transducer of cross according to claim 3 orthogonal composite flooding piezoelectricity, it is characterised in that described cross orthogonal complex centre mass is one-body molded。

5. the tubular transducer of cross according to claim 1 orthogonal composite flooding piezoelectricity, it is characterised in that described piezoelectric ceramic wafer is circular。

6. the tubular transducer of cross according to claim 5 orthogonal composite flooding piezoelectricity, it is characterised in that described electrode slice includes electrode portion and connecting portion, described connecting portion is affixed with described electrode portion, and described connecting portion is for being connected with power supply；Described electrode portion is the circle identical with described piezoelectric ceramic wafer profile, and described electrode portion overlaps with described piezoelectric ceramic wafer and stacks。

7. the tubular transducer of cross according to claim 1 orthogonal composite flooding piezoelectricity, it is characterised in that four described outer masses and described radial radiation housing integrated molding。

8. the cross orthogonal composite flooding tubular transducer of piezoelectricity according to any one of claim 1-7, it is characterised in that described radial radiation housing two ends have also been respectively and fixedly connected with waterproof sealing lid。

9. the tubular transducer of cross according to claim 8 orthogonal composite flooding piezoelectricity, it is characterised in that two described waterproof sealing lids are connected by screw with described radial radiation housing。

10. the tubular transducer of cross according to claim 9 orthogonal composite flooding piezoelectricity, it is characterised in that be respectively arranged with sealing ring between two described waterproof sealing lids and described radial radiation housing。