Magnetostrictive transducer

Abstract

The invention discloses a magnetostrictive transducer, which comprises: a housing; the backing is arranged at one end of the shell in a sealed manner; one end of the magnetic core is fixedly connected with the backing, the magnetic core extends along the length of the shell and is arranged in the shell, and a coil is wound on the outer surface of the magnetic core; the amplitude-change pole is made of a material with the magnetostriction coefficient opposite to the magnetostriction coefficient of the magnetic core, the amplitude-change pole is fixedly connected with the other end of the magnetic core, and the amplitude-change pole is arranged at the other end of the shell in a closed mode; the backing, the magnetic core and the amplitude-change pole are sequentially connected and form a closed magnetic loop with the shell, materials with positive and negative magnetostriction coefficients are combined in the same magnetic loop, when the coil generates a magnetic field, the magnetic core with magnetostriction and the amplitude-change pole are subjected to the action of the magnetic field, the positive value material is excited to longitudinally extend, and the positive value material is excited to longitudinally extend. And meanwhile, the negative value material is excited to longitudinally shrink, so that a high-power transducer with high energy conversion efficiency is formed.

Description

Technical Field

[0001] The present invention relates to the technical field of transducers, and in particular to a magnetostrictive transducer. Background Art

[0002] Magnetostrictive transducer is an electroacoustic conversion device based on the magnetostrictive effect of materials. It is mainly used in the fields of ultrasound and hydroacoustics and can generate high-intensity sound waves within a certain frequency range. Magnetostrictive transducer has the characteristics of simple structure and strong resistance to mechanical shock and electrical shock. It has good application prospects in some harsh environmental conditions. Magnetostrictive materials can be divided into nickel-based materials, iron-based materials, iron-gallium-based materials, ferrite materials, and rare earth materials according to their composition. Among them, rare earth magnetostrictive materials have large strain values, but low tensile strength, large brittleness, and high material and processing costs. Non-rare earth magnetostrictive materials have good mechanical properties and high strength, but the saturation strain value is not high and the energy conversion efficiency is low.

[0003] The currently adopted scheme is as follows: The patent application with application number CN201521095907.7 discloses a dual-excitation piezoelectric transducer, which divides the ceramic element used for excitation into two parts, a front and a rear part. When working, the voltages applied to the front and rear elements are reversed, so that the elements vibrate in opposite forms at the same time, and drive the transducer to vibrate in a "compression-relaxation" vibration mode. The defect is that the front and rear ceramic elements used in this scheme require high consistency in mechanical and electrical parameters, otherwise synchronous vibration cannot be achieved, which places high requirements on the elements and processing technology.

[0004] At present, rare earth magnetostrictive materials are brittle, have low tensile strength, and are much more expensive than non-rare earth materials, which limits their large-scale application. Non-rare earth magnetostrictive materials have a small saturation magnetostriction coefficient and low electroacoustic conversion efficiency. Structurally, rare earth magnetostrictive transducers are mainly designed as straight rods. In order to reduce eddy current heating, the straight rods are cut axially symmetrically or axially parallel and then re-bonded into straight rods. Affected by the brittleness of the material, the characteristic size of the cutting is large, and the effect on eddy current control is limited. It cannot be used in long-term high-power working scenarios in the ultrasonic frequency band; the magnetic circuit is not closed, and a magnetic yoke needs to be designed separately, which occupies a large space, and the vibration during operation will affect the connection state of the magnetic conductive mechanism and the magnetostrictive material. Non-rare earth magnetostrictive transducers are mainly rolled into thin sheets, cut into window-type structures, and then multiple thin sheets are stacked into transducers. The window-type structure has a low material utilization rate, and the actual output power depends on the volume of the magnetostrictive material on both sides of the window; the window-type structure is easy to introduce bending vibration modes, which reduces the longitudinal output efficiency. Summary of the invention

[0005] The purpose of the present invention is to provide a magnetostrictive transducer, which uses non-rare earth magnetostrictive materials to design a high-power transducer with high energy conversion efficiency, which is suitable for high-power application scenarios.

[0006] The present invention provides a magnetostrictive transducer, comprising: shell; A backing, the backing being closed and disposed at one end of the shell; A magnetic core, wherein the magnetic core is formed by stacking and gluing thin sheets of magnetostrictive material, one end of the magnetic core is fixedly connected to the backing, and the magnetic core extends along the length of the shell and is arranged in the shell, and a plurality of coils are wrapped around the outer surface of the magnetic core; A horn, wherein the horn is made of magnetostrictive material, the magnetostriction coefficient of the horn is made of a material with a positive and negative opposite magnetostriction coefficient to that of the magnetic core, the horn is fixedly connected to the other end of the magnetic core, and the horn is closed and arranged at the other end of the housing; Among them, the backing, magnetic core and amplitude transformer are connected in sequence and form a closed magnetic circuit with the shell, and materials with opposite positive and negative magnetostrictive coefficients are combined in the same magnetic circuit. When the coil generates a magnetic field, the magnetic core and amplitude transformer with magnetostriction are affected by the magnetic field, and the positive value material is excited to stretch longitudinally, while the negative value material is excited to contract longitudinally, forming a push-pull action.

[0007] Preferably, the magnetic core is made of magnetostrictive sheets processed into rectangular sheets, which are then stacked and glued together, wherein when the magnetic core is made of a material with a positive magnetostrictive coefficient, the amplitude transformer is made of a material with a negative magnetostrictive coefficient; or when the magnetic core is made of a material with a negative magnetostrictive coefficient, the amplitude transformer is made of a material with a positive magnetostrictive coefficient.

[0008] Preferably, the amplitude transformer is slit along the axial direction of the magnetic core on the side connected to the magnetostrictive sheet and an insulating glue layer is provided in the slit.

[0009] Preferably, a cooling tube is provided between the magnetic core and the coil and along the outer surface of the magnetic core, and the cooling tube is a non-magnetic metal tube.

[0010] Preferably, the shell is a soft ferromagnetic metal structure, and the backing is a soft ferromagnetic metal structure.

[0011] Preferably, the magnetic core includes a first magnetostrictive segment and a second magnetostrictive segment, the first magnetostrictive segment and the second magnetostrictive segment are respectively composed of materials with opposite magnetostriction coefficient values, the first magnetostrictive segment and the second magnetostrictive segment are fixedly connected, and the two ends of the first magnetostrictive segment and the second magnetostrictive segment are respectively connected to the backing and the amplitude rod.

[0012] Preferably, the flange on the horn structure itself is connected to the housing by screws.

[0013] Preferably, the backing is connected to the shell by bolts.

[0014] Preferably, a water inlet is provided on the side wall of the shell.

[0015] Preferably, the structure of the amplitude transformer is any one of a stepped shape, a conical shape, an exponential shape, a catenary shape and a composite amplitude transformer.

[0016] Due to the adoption of the above technical solution, the present invention has the following advantages and positive effects compared with the prior art: 1. The magnetostrictive transducer provided by the present invention is designed to make the magnetic circuit smoother by sequentially connecting the housing, backing, magnetic core and amplitude transformer to form a closed magnetic circuit and coaxially arranged. When the coil generates a magnetic field, it can effectively reduce the magnetic resistance, enhance the transfer efficiency of the magnetic flux, and allow the magnetic energy to act more efficiently on the magnetic core and the amplitude transformer, thereby realizing the efficient conversion of electrical energy to mechanical energy; the backing is closed at one end of the housing, and the amplitude transformer is closed at the other end of the housing, which effectively protects the internal components. At the same time, the components are connected by fixed connection, screw connection or bolt connection, which enhances the overall stability of the structure, reduces the risk of loosening and damage of components due to vibration, impact and other factors, and improves the reliability and service life of the transducer.

[0017] 2. The magnetic core used in the present invention is formed by stacking and gluing magnetostrictive sheets. The material with a positive or negative magnetostrictive coefficient is selected according to the needs. The horn is composed of a material with a magnetostrictive coefficient opposite to that of the magnetic core. This combination makes the positive material and the negative material cooperate with each other under the action of the magnetic field. For example, when the magnetic core of the positive material is longitudinally extended under the excitation of the magnetic field, the horn of the negative material will shrink longitudinally, forming a push-pull action, which greatly increases the longitudinal strain output of the transducer, improves the magnetostrictive efficiency and mechanical output capacity of the transducer, and improves the efficiency of energy utilization and power capacity through the composition of the two materials.

[0018] 3. The design of the magnetic core used in the present invention including the first magnetostrictive section and the second magnetostrictive section also increases the flexibility of the structural design. By selecting materials with different magnetostrictive coefficients with opposite positive and negative values ​​to form the two sections, the overall magnetostrictive performance of the magnetic core can be more finely adjusted, thereby optimizing the magnetic field distribution and strain characteristics of the transducer.

[0019] 4. The present invention performs slit processing along the axial direction of the magnetic core on one side of the amplitude rod connected to the magnetostrictive sheet and provides an insulating rubber layer in the slit, which can effectively reduce the heat generated by eddy currents and improve energy conversion efficiency. The design of a cooling tube surrounding the outer surface of the magnetic core between the magnetic core and the coil and a water outlet on the side wall of the shell can effectively solve the problem of heat generated by the transducer during operation. The circulation of the coolant in the cooling tube and the heat dissipation of the water outlet can timely remove the heat, ensure that the various components of the transducer work within a suitable temperature range, reduce performance degradation and component damage caused by overheating, and improve the working efficiency and reliability of the transducer. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a plan view of the structure of a magnetostrictive transducer in an embodiment of the present invention; Figure 2 is a magnetic circuit diagram of a magnetostrictive transducer in an embodiment of the present invention; Figure 3 is a vibration mode diagram of a magnetostrictive transducer in an embodiment of the present invention; Among them, 1-housing; 2-backing; 3-magnetic core; 4-coil; 5-amplifier; 6-cooling tube. DETAILED DESCRIPTION

[0021] The following is an explanation of the embodiments of the present invention by specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be understood that the orientation or position relationship indicated by the terms "center", "longitudinal", "lateral", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc. is based on the orientation or position relationship shown in the drawings, which is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention. In addition, the terms "first", "second", etc. are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, the features defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, the meaning of "multiple" is two or more.

[0022] It should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood by specific circumstances.

[0023] like Figure 1-3 As shown, an embodiment of the present invention provides a magnetostrictive transducer, that is, a non-rare earth magnetostrictive transducer with high power and high energy conversion efficiency, comprising: Shell 1; The backing 2 is sealed and arranged at one end of the housing 1; the backing 2 is made of soft ferromagnetic metal material, axially cut, the cut structure is similar to the amplitude transformer 5, and is filled with insulating glue, and the backing 2 is connected to the rear cover of the housing 1.

[0024] A magnetic core 3, wherein the magnetic core 3 is formed by stacking and gluing thin sheets of magnetostrictive material, one end of the magnetic core 3 is fixedly connected to the backing 2, and the magnetic core 3 extends along the length of the shell 1 and is arranged in the shell 1, and a plurality of coils 4 are surrounded on the outer surface of the magnetic core 3, and the wire adopts a high temperature resistant insulation layer; A horn 5, wherein the horn 5 is made of magnetostrictive material, the magnetostriction coefficient of the horn 5 is made of a material with a positive and negative opposite magnetostriction coefficient to that of the magnetic core 3, the horn 5 is fixedly connected to the other end of the magnetic core 3, and the horn 5 is closed and arranged at the other end of the housing 1; The backing 2, the magnetic core 3 and the horn 5 are connected in sequence and form a closed magnetic circuit with the shell 1, and materials with opposite magnetostrictive coefficients are combined in the same magnetic circuit. When the coil 4 generates a magnetic field, the magnetic core 3 and the horn 5 with magnetostrictive properties are acted upon by the magnetic field, and the positive value material is excited to extend longitudinally, while the negative value material is excited to contract longitudinally, forming a push-pull action, that is, materials with positive and negative magnetostrictive coefficients are combined to synchronously realize a compression-relaxation push-pull excitation mode in the same magnetic circuit, thereby improving the electroacoustic conversion efficiency. This method is different from a dual-excitation piezoelectric transducer, and does not require two excitation elements to be connected separately, and synchronous excitation of different materials can be realized with only one set of coils 4. The horn 5, the backing 2 and the shell 1 form a magnetic circuit with the magnetic core 3, and the horn 5 is selected to be tightly connected to the shell 1 at the vibration displacement node, thereby avoiding the influence of large-amplitude vibration of the magnetostrictive material on the magnetic circuit.

[0025] It can be understood that the transducer used in the embodiment of the present invention is composed of a magnetic core 3, a horn 5, a housing 1, a backing 2, a cooling tube 6, and a coil 4. The transducer structure is as follows Figure 1 As shown, the magnetic core 3 is connected to the horn 5, and the contact surface is polished and connected by adhesive or welding. The horn 5 is tightly connected to the housing 1 by screws through the flange in its structure. The magnetic core 3 is tightly connected to the backing 2, and the contact surface is polished and connected by adhesive or welding. The backing 2 is connected to the housing 1 by bolts to form a complete magnetic circuit. In the embodiment of the present invention, the magnetic core 3 and the horn 5 with opposite magnetostrictive coefficients are combined in the same magnetic circuit, and a push-pull action can be formed when the coil 4 generates a magnetic field. For example, when the magnetostrictive coefficient of the magnetic core 3 is positive, it will be longitudinally stretched under the excitation of the magnetic field, and when the magnetostrictive coefficient of the horn 5 is negative, it will shrink longitudinally. Compared with a single material, this synergistic effect greatly enhances the overall longitudinal strain capacity of the transducer, makes the mechanical output larger, and can effectively improve the efficiency of converting magnetic energy into mechanical energy. By designing that the multi-strand coil 4 surrounds the magnetic core 3, the magnetic field can act more evenly on the magnetic core 3 and the horn 5. At the same time, the closed magnetic circuit structure reduces magnetic resistance, effectively improves the utilization rate of the magnetic field, and allows magnetic energy to be more efficiently converted into the telescopic movement of the magnetic core 3 and the horn 5, further improving the performance of the transducer. The backing 2 is closed at one end of the shell 1, and the horn 5 is closed at the other end of the shell 1, and the backing 2, the magnetic core 3 and the horn 5 are connected in sequence to form a closed structure, which provides good protection for the internal components. Compared with the split or semi-open structure, it can effectively prevent the external environmental factors from interfering with and damaging the internal components, and enhance the structural stability of the entire transducer. One end of the magnetic core 3 is fixedly connected to the backing 2, and the other end is fixedly connected to the horn 5. A reliable connection method is used to ensure that the connection between the components is firm. During long-term use, it can reduce the occurrence of problems such as loosening and wear of components due to external forces such as vibration and impact, thereby improving the reliability and service life of the transducer. The magnetic core 3 is composed of magnetostrictive material sheets stacked and glued together. This structure increases the number and thickness of the insulation layer to a certain extent. At the same time, the use of different magnetostrictive materials between the amplitude transformer 5 and the magnetic core 3 also helps to improve the insulation performance. Good insulation performance can prevent current leakage and ensure the safe operation of the transducer, especially in some high-voltage, high-frequency and other working environments, and can effectively avoid the occurrence of safety problems such as short circuits.

[0026] In one embodiment, the magnetic core 3 is made of magnetostrictive thin sheets processed into rectangular thin sheets, which are then stacked and glued together. When the magnetic core 3 is made of a material with a positive magnetostrictive coefficient, the horn 5 is made of a material with a negative magnetostrictive coefficient; or, when the magnetic core 3 is made of a material with a negative magnetostrictive coefficient, the horn 5 is made of a material with a positive magnetostrictive coefficient. In this embodiment, after the rectangular thin sheet-shaped magnetic core 3 is stacked, its cross-sectional shape and area help to more effectively guide and concentrate the magnetic flux. Compared with other irregular shapes, the rectangular structure can make the magnetic flux more evenly distributed inside the magnetic core 3, reduce magnetic flux leakage, and thus increase the magnetic flux density of the magnetic circuit. This is conducive to generating a stronger magnetic field acting on the magnetic core 3 and the horn 5 under the same excitation conditions, thereby improving the magnetostrictive performance of the transducer. The manufacturing method of stacking and gluing thin sheets makes the contact between the layers of the magnetic core 3 close and uniform. This close connection reduces the air gap and discontinuity points inside the magnetic core 3, thereby reducing the magnetic resistance. The reduction of magnetic resistance means that when the coil 4 generates a magnetic field, the magnetic energy loss is reduced, and more magnetic energy can effectively act on the magnetic core 3 and the horn 5, thereby improving the efficiency of the transducer. When the magnetic core 3 is made of a material with a positive magnetostriction coefficient, and the horn 5 is made of a material with a negative magnetostriction coefficient (and vice versa), a push-pull action is formed under the action of the magnetic field. This combination method makes the magnetostrictive characteristics of the transducer in different directions complement and enhance each other. For example, under the excitation of the magnetic field, the elongation of the magnetic core 3 and the contraction of the horn 5 work together to produce a greater longitudinal strain. Compared with a transducer made of a single material, this structural design greatly improves the mechanical output capacity of the transducer, enabling it to perform well in applications that require large displacement or force output. The magnetic core 3 is made of stacked thin sheets, which increases the strength and rigidity of the structure. When subjected to external vibration, impact and other forces, this structure is less likely to deform or damage. At the same time, the magnetic core 3 and the amplitude transformer 5 are fixedly connected by gluing or other means, which further enhances the stability of the overall structure, helps the transducer maintain reliable performance in different working environments, and reduces the risk of failure due to structural looseness or damage.

[0027] In one embodiment, the horn 5 is slitted along the axial direction of the magnetic core 3 on the side connected to the magnetostrictive thin sheet and an insulating adhesive layer is provided in the slit, which effectively cuts off the possible leakage path of the current. When the transducer is working, the magnetic field generated by the coil 4 will cause the magnetic core 3 and the horn 5 to produce a magnetostrictive effect, and good insulation can ensure that the current will not form a loop between the magnetic core 3, the horn 5 and the housing 1, thereby avoiding the influence of current leakage on the performance of the transducer and ensuring the normal operation of the transducer. The presence of the insulating adhesive layer can improve the insulation strength between the horn 5 and the magnetic core 3, so that it can withstand higher voltages. The slit treatment can form a stress release area at the connection between the horn 5 and the magnetic core 3. During the operation of the transducer, the expansion and contraction of the magnetic core 3 will be transmitted through the horn 5. The slit can alleviate the stress concentration phenomenon at the connection part, reduce the material fatigue, cracking and other damages that may be caused by stress concentration, and improve the mechanical reliability and service life of the transducer. Among them, the insulating adhesive layer is formed by high temperature resistant (operating temperature> 250°C) adhesives such as silicone, silicate, and phosphate.

[0028] In one embodiment, a cooling tube 6 is provided between the magnetic core 3 and the coil 4 along the outer surface of the magnetic core 3. The cooling tube 6 is made of a non-magnetic metal tube. The non-magnetic metal material usually has a high thermal conductivity, such as copper, aluminum, etc., which can quickly conduct the heat generated by the magnetic core 3 to avoid heat accumulation in the magnetic core 3 and the coil 4. For example, in the operation of some high-power transducers, the magnetic core 3 will generate a large amount of heat due to the frequent changes in the magnetostrictive effect. The cooling tube 6 can quickly transfer this heat to the surrounding environment, keep the magnetic core 3 at a lower temperature level, and thus ensure the normal operation of the transducer. The cooling tube 6 surrounds the outer surface of the magnetic core 3. Compared with the traditional heat dissipation method, the cooling tube 6 greatly increases the heat dissipation area, can fully contact the outer surface of the magnetic core 3, and can dissipate heat from all directions, thereby improving the heat dissipation efficiency. Especially in some application scenarios with high requirements for heat dissipation, such as industrial transducers that work continuously for a long time or ultrasonic transducers with high power density, the increased heat dissipation area can effectively reduce the temperature of the magnetic core 3 and reduce the risk of performance degradation due to overheating. Since the cooling tube 6 is made of a non-magnetic metal tube, it will not interfere with the magnetic field around the magnetic core 3. When the transducer is working, the magnetic field generated by the magnetic core 3 needs to maintain a certain uniformity and stability to ensure the effective conversion of the magnetostrictive effect. If the cooling tube 6 is a magnetic material, it may change the distribution of the magnetic field and affect the performance of the transducer. The non-magnetic metal tube can avoid this situation, so that the magnetic field can act on the magnetic core 3 and the horn 5 in the designed manner, thereby improving the energy conversion efficiency of the transducer. The reasonable layout of the cooling tube 6 helps to ensure the integrity of the magnetic circuit. When winding the coil 4, the presence of the cooling tube 6 will not destroy the magnetic field loop generated by the coil 4. On the contrary, it can provide a good heat dissipation channel for the magnetic core 3 without changing the magnetic field loop, so that the magnetic core 3 can better respond to changes in the magnetic field, thereby achieving more stable magnetostrictive performance, and then improving the working performance of the entire transducer. Among them, the cooling tube 6 is made of copper or aluminum tube, and water, compressed air or other coolants are passed through it.

[0029] In one embodiment, the shell 1 is a soft ferromagnetic metal structure, and the backing 2 is a soft ferromagnetic metal structure. Soft ferromagnetic metal has a high magnetic permeability, which means that the shell 1 and the backing 2 can effectively concentrate and guide the magnetic field lines. When the coil 4 generates a magnetic field, the shell 1 and the backing 2 of the soft ferromagnetic metal can gather the magnetic field around the magnetic core 3, reduce the leakage of the magnetic field, and thus form a stronger magnetic field in the magnetic core 3. For example, in an electromagnetic transducer, a stronger magnetic field can cause the magnetic core 3 to produce a more significant magnetostrictive effect, thereby improving the efficiency of the transducer in converting electrical energy into mechanical energy (or vice versa). The characteristics of soft ferromagnetic metal help to make the magnetic field around the magnetic core 3 more uniform. A uniform magnetic field is essential for the stable operation of the transducer because it ensures that the magnetic core 3 is subjected to a consistent magnetic force throughout the volume, thereby producing uniform magnetostriction. This can ensure the stability and reliability of its performance for some application scenarios with high precision requirements, such as transducers in ultrasonic imaging and precision manufacturing. The soft ferromagnetic metal shell 1 can act as a magnetic shield to prevent external stray magnetic fields from entering the interior of the transducer. In actual application environments, such as factory workshops or hospitals, there are magnetic fields generated by various electromagnetic devices, and these external magnetic fields may interfere with the normal operation of the transducer. The soft ferromagnetic metal shell 1 can absorb and offset most of the external magnetic field, so that the magnetic field environment inside the transducer remains relatively stable, thereby improving its anti-interference ability. At the same time, the backing 2, as a soft ferromagnetic metal structure, can also cooperate with the shell 1 to further reduce the electromagnetic radiation generated by the transducer itself, which helps to meet the electromagnetic compatibility (EMC) standards, especially in the fields of medical equipment, aerospace equipment, etc., which have strict restrictions on electromagnetic radiation. Reducing electromagnetic radiation can prevent interference with other electronic equipment and ensure the normal operation of the entire system.

[0030] In one embodiment, the magnetic core 3 includes a first magnetostrictive segment and a second magnetostrictive segment, wherein the first magnetostrictive segment and the second magnetostrictive segment are respectively structures composed of materials with opposite magnetostrictive coefficient values, the first magnetostrictive segment and the second magnetostrictive segment are fixedly connected, and the two ends of the first magnetostrictive segment and the second magnetostrictive segment are respectively connected to the backing 2 and the horn 5. Since the magnetostrictive coefficient values ​​of the first magnetostrictive segment and the second magnetostrictive segment are opposite in positive and negative, under the action of the magnetic field, when one magnetostrictive segment contracts, the other magnetostrictive segment will stretch, and this bidirectional magnetostrictive characteristic can compensate each other, reducing the internal stress concentration of the material caused by magnetostriction in a single direction. For example, in some high-precision transducer applications, such as precision flow control or micro-displacement detection, this bidirectional compensation mechanism can enable the transducer to maintain better structural stability during operation, thereby improving its accuracy and reliability. By combining two materials with opposite magnetostrictive coefficients, the magnetostrictive strain range of the entire magnetic core 3 can be expanded. Compared with a single magnetostrictive material, this composite structure can produce a larger size change under the same magnetic field change, which is very beneficial for transducer applications that require a larger displacement or vibration amplitude, such as ultrasonic generators or vibration sensors, and can effectively improve their working efficiency and performance. The first magnetostrictive segment and the second magnetostrictive segment are fixedly connected, and the two ends are respectively connected to the backing 2 and the amplitude rod 5, forming a relatively closed magnetic circuit structure, which helps to reduce the leakage of the magnetic field in the non-working area (such as the air around the magnetic core 3), so that the magnetic field is more concentrated inside the magnetic core 3, thereby improving the utilization efficiency of the magnetic field. In an electromagnetic transducer, a higher magnetic field utilization efficiency means that a stronger magnetic field can be generated under the same input power, thereby enhancing the magnetostrictive effect and improving the performance of the transducer. Due to the connection method of the two sections of magnetostrictive material, the magnetic field is more evenly distributed inside the magnetic core 3. The uniform magnetic field can ensure that magnetostriction occurs more uniformly over the entire length of the magnetic core 3, avoiding local excessive expansion or contraction due to uneven magnetic field, and improving the energy conversion efficiency and working stability of the transducer.

[0031] In one embodiment, the flange on the structure of the horn 5 is connected to the housing 1 by screws, which can ensure a tight and stable connection between the horn 5 and the housing 1. During the operation of the transducer, whether it is the vibration generated by the internal magnetic field force or the mechanical shock or vibration of the external environment, this screw connection can effectively resist and ensure that the relative position of the horn 5 and the housing 1 will not shift, thereby improving the stability of the transducer structure. For example, in some high-power ultrasonic transducers used in industrial sites, a stable connection can prevent components from loosening due to vibration, affecting the normal operation of the transducer.

[0032] When installing the horn 5, the concentricity of the horn 5 and the housing 1 can be ensured by evenly tightening the screws. Good concentricity helps to make the magnetic field distribution inside the transducer more uniform, reduce the magnetic field distortion caused by the non-concentricity of components, and thus improve the efficiency and stability of the magnetostrictive effect.

[0033] In one embodiment, the backing 2 is connected to the shell 1 by bolts, and the backing 2 and the shell 1 are made of soft magnetic materials such as pure iron and silicon steel.

[0034] In one embodiment, a water port is provided on the side wall of the housing 1. During the operation of the transducer, heat is generated to increase its temperature. When a water port is provided on the side wall of the housing 1, cooling water can be introduced or water can be allowed to circulate inside the housing 1. Water has a large specific heat capacity and can absorb a large amount of heat. For example, in some high-power industrial transducers, a lot of heat is generated. By injecting circulating cooling water through the water port, the heat can be quickly taken away, keeping the transducer working within a suitable temperature range, and avoiding degradation or damage to component performance due to overheating. By reasonably arranging the water ports, the cooling water can form a relatively uniform flow path in the housing 1, thereby dissipating heat more comprehensively to each heating part. This helps to improve the uniformity of heat dissipation of the entire transducer, reduce local overheating, and further improve the performance of the transducer.

[0035] In one embodiment, the structure of the horn 5 is any one of a stepped shape, a conical shape, an exponential shape, a catenary shape, and a composite horn 5. The materials of the magnetic core 3 and the horn 5 can be selected from materials with magnetostrictive properties such as iron-aluminum alloy, iron-nickel alloy, iron-cobalt alloy, iron-gallium alloy, and pure nickel, wherein the magnetic core 3 and the horn 5 are respectively composed of materials with opposite positive and negative magnetostrictive coefficient values. The magnetic core 3 can be made of a material with a positive magnetostrictive coefficient and a negative magnetostrictive coefficient of the horn 5; or the magnetic core 3 can be made of a material with a negative magnetostrictive coefficient and a positive magnetostrictive coefficient of the horn 5.

[0036] The embodiments of the present invention are described in detail above in conjunction with the accompanying drawings, but the present invention is not limited to the above embodiments. Even if various changes are made to the present invention, if these changes fall within the scope of the claims of the present invention and their equivalents, they still fall within the protection scope of the present invention.

Claims

1. A magnetostrictive transducer, characterized in that: include: shell; A backing, the backing being closed and disposed at one end of the shell; A magnetic core, wherein the magnetic core is formed by stacking and gluing thin sheets of magnetostrictive material, one end of the magnetic core is fixedly connected to the backing, and the magnetic core extends along the length of the shell and is arranged in the shell, and a plurality of coils are wrapped around the outer surface of the magnetic core; A horn, wherein the horn is made of magnetostrictive material, the magnetostriction coefficient of the horn is made of a material with a positive and negative opposite magnetostriction coefficient to that of the magnetic core, the horn is fixedly connected to the other end of the magnetic core, and the horn is closed and arranged at the other end of the housing; Among them, the backing, magnetic core and amplitude transformer are connected in sequence and form a closed magnetic circuit with the shell, and materials with opposite positive and negative magnetostrictive coefficients are combined in the same magnetic circuit. When the coil generates a magnetic field, the magnetic core and amplitude transformer with magnetostriction are affected by the magnetic field, and the positive value material is excited to stretch longitudinally, while the negative value material is excited to contract longitudinally, forming a push-pull action.

2. The magnetostrictive transducer according to claim 1, characterized in that: The magnetic core is made of magnetostrictive sheets processed into rectangular sheets, which are then stacked and glued together. When the magnetic core is made of a material with a positive magnetostrictive coefficient, the horn is made of a material with a negative magnetostrictive coefficient; or when the magnetic core is made of a material with a negative magnetostrictive coefficient, the horn is made of a material with a positive magnetostrictive coefficient.

3. The magnetostrictive transducer according to claim 2, characterized in that: The amplitude transformer is cut along the axial direction of the magnetic core on the side connected to the magnetostrictive sheet, and an insulating glue layer is arranged in the cut.

4. The magnetostrictive transducer according to claim 1, characterized in that: A cooling pipe is arranged between the magnetic core and the coil along the outer surface of the magnetic core, and the cooling pipe is a non-magnetic metal pipe.

5. The magnetostrictive transducer according to claim 1, characterized in that: The shell is a soft ferromagnetic metal structure, and the backing is a soft ferromagnetic metal structure.

6. The magnetostrictive transducer according to claim 1, characterized in that: The magnetic core includes a first magnetostrictive segment and a second magnetostrictive segment, the first magnetostrictive segment and the second magnetostrictive segment are respectively made of materials with opposite magnetostrictive coefficient values, the first magnetostrictive segment and the second magnetostrictive segment are fixedly connected, and the first magnetostrictive segment and the second magnetostrictive segment are respectively connected to the backing and the amplitude rod at both ends.

7. The magnetostrictive transducer according to claim 1, characterized in that: The flange on the horn structure itself is connected to the shell through screws.

8. The magnetostrictive transducer according to claim 1, characterized in that: The backing is connected to the shell by bolts.

9. The magnetostrictive transducer according to claim 1, characterized in that: A water opening is arranged on the side wall of the shell.

10. The magnetostrictive transducer according to claim 1, characterized in that: The structure of the horn is any one of a stepped shape, a conical shape, an exponential shape, a catenary shape and a composite horn.

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