Ultrasonic transducer

Abstract

The utility model relates to an ultrasonic transducer, which comprises a cylindrical shell with a first sound transmission hole at one end; the at least two piezoelectric ceramic pieces are coaxially arranged in the shell at intervals, are sequentially arranged on different horizontal planes from outside to inside, and are mutually independent; each piezoelectric ceramic piece and the corresponding first sound transmission hole are coaxially arranged, ultrasonic energy generated by the piezoelectric ceramic pieces is transmitted out through the corresponding first sound transmission hole, focus points of all the piezoelectric ceramic pieces are located on the same central axis, and except the piezoelectric ceramic piece on the innermost side, the other piezoelectric ceramic pieces are provided with through holes; the through hole and the other adjacent piezoelectric ceramic piece are coaxially arranged so that ultrasonic energy can penetrate out of the through hole. According to the ultrasonic transducer, different focusing depths can be achieved, the requirement problem of ultrasonic focusing of multiple focusing points is effectively solved, especially the focusing requirement with different depths is met, and the ultrasonic transducer has the advantages of being simple in structure and compact in structure.

Description

Technical Field

[0001] The utility model relates to the field of ultrasonic application, in particular to an ultrasonic transducer. Background Art

[0002] The ultrasonic transducer in the related technology usually adopts a single piezoelectric ceramic. When there is a demand for ultrasound focusing at multiple focal points, especially when there is a need for focusing with different depths, the existing technology is to install a motor on a single piezoelectric ceramic chip to achieve it. Its structure is not only complex, but also increases the demand for installation space. Utility Model Content

[0003] The technical problem to be solved by the utility model is to provide an improved ultrasonic transducer.

[0004] The technical solution adopted by the utility model to solve the technical problem is: construct an ultrasonic transducer, including:

[0005] The outer shell is cylindrical and has a first sound-permeable hole at one end;

[0006] At least two piezoelectric ceramic sheets are coaxially spaced in the housing, arranged in sequence from the outside to the inside at different horizontal planes, and are independent of each other; each piezoelectric ceramic sheet is coaxially arranged with the first sound-permeable hole, and the ultrasonic energy generated by it is transmitted through the first sound-permeable hole, and the focusing points of all the piezoelectric ceramic sheets are on the same central axis, and except for the innermost piezoelectric ceramic sheet, the other piezoelectric ceramic sheets have through holes; the through holes are coaxially arranged with another adjacent piezoelectric ceramic sheet for ultrasonic energy to pass through.

[0007] In some embodiments, the piezoelectric ceramic sheet is arched toward a side away from the first sound-transmitting hole so that the ultrasonic energy is focused on the central axis of the piezoelectric ceramic sheet.

[0008] In some embodiments, radial dimensions of at least two of the piezoelectric ceramic sheets gradually decrease from outside to inside.

[0009] In some embodiments, the ultrasonic transducer further comprises:

[0010] A fixing frame is disposed in the housing and is provided with a second sound-transmitting hole disposed opposite to the first sound-transmitting hole;

[0011] At least two piezoelectric ceramic sheets, including:

[0012] A first piezoelectric ceramic sheet is disposed in the housing and installed between the fixing frame and the first sound-permeable hole; the first piezoelectric ceramic sheet is provided with the through hole communicating with the second sound-permeable hole and the first sound-permeable hole;

[0013] The second piezoelectric ceramic sheet is mounted on the fixing frame and is coaxially arranged with the second sound-permeable hole.

[0014] In some embodiments, a limit stop is provided at one end of the housing, and the limit stop is provided in the first sound-transmitting hole along the circumference of the first sound-transmitting hole, and is used for limiting the installation of the first piezoelectric ceramic sheet.

[0015] In some embodiments, a first buffer pad is disposed between the first piezoelectric ceramic sheet and the limit stop.

[0016] In some embodiments, a second buffer pad is disposed between the first piezoelectric ceramic sheet and the fixing frame.

[0017] In some embodiments, the inner wall of the housing is provided with at least one limiting groove for limiting the installation of the fixing frame;

[0018] The fixing frame includes a cylinder and at least two clamping parts arranged on the outer periphery of the cylinder; the cylinder is hollow to form the second sound-transmitting hole;

[0019] The clamping portion extends toward the inner side wall of the shell to be clamped into the limiting groove.

[0020] In some embodiments, the fixing frame is provided with a limiting hook, and the limiting hook extends toward a side opposite to the first sound-permeable hole, and is used for limiting the installation of the second piezoelectric ceramic sheet.

[0021] In some embodiments, a third buffer pad is disposed between the second piezoelectric ceramic sheet and the fixing frame.

[0022] The implementation of the ultrasonic transducer of the utility model has the following beneficial effects: the ultrasonic transducer is provided with at least two piezoelectric ceramic sheets which are coaxially spaced and independent of each other, and at least two piezoelectric ceramic sheets are arranged in sequence from the outside to the inside on different horizontal planes, each piezoelectric ceramic sheet is coaxially arranged with the first sound-transmitting hole, and the ultrasonic energy generated by it is transmitted through the first sound-transmitting hole, and the focusing points of all the piezoelectric ceramic sheets are on the same central axis, except for the innermost piezoelectric ceramic sheet, the remaining ceramic sheets on the fixed frame are provided with through holes which are coaxially arranged with another adjacent piezoelectric ceramic sheet for the ultrasonic energy to pass through, thereby optimizing the installation space of multiple piezoelectric ceramic sheets, achieving different focusing depths, and effectively solving the problem of the need for multiple focusing points of ultrasonic focusing, especially the focusing needs with different depths, and the ultrasonic transducer has the advantages of simple structure and compact structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The present invention will be further described below with reference to the accompanying drawings and embodiments, in which:

[0024] Figure 1is a cross-sectional view of an ultrasonic transducer according to a first embodiment of the utility model;

[0025] Figure 2 yes Figure 1 Another cross-sectional view of the ultrasonic transducer shown;

[0026] Figure 3 yes Figure 1 A schematic diagram of the structure decomposition of the ultrasonic transducer shown;

[0027] Figure 4 is a cross-sectional view of an ultrasonic transducer according to a second embodiment of the present utility model;

[0028] Figure 5 yes Figure 4 Schematic diagram of the structural decomposition of the ultrasonic transducer shown. DETAILED DESCRIPTION

[0029] In order to have a clearer understanding of the technical features, purposes and effects of the utility model, the specific implementation methods of the utility model are now described in detail with reference to the accompanying drawings. In the following description, it should be understood that the directions or positional relationships indicated by "upper", "lower", "horizontal", "inner", "outer", etc. are based on the directions or positional relationships shown in the accompanying drawings, and are constructed and operated in a specific direction. They are only for the convenience of describing the technical solution, and do not indicate that the device or element referred to must have a specific direction, and therefore cannot be understood as a limitation on the utility model.

[0030] It should also be noted that, unless otherwise clearly specified and limited, the terms such as "installation", "connection", "fixation", "setting", etc. should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. When an element is referred to as being "on" or "under" another element, the element can be "directly" or "indirectly" located on the other element, or there may be one or more intermediate elements. The terms "first", "second", "third", etc. are only for the convenience of describing the present technical solution, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first", "second", "third", etc. can explicitly or implicitly include one or more of the features. For ordinary technicians in this field, the specific meanings of the above terms in the present utility model can be understood according to the specific circumstances.

[0031] In the following description, specific details such as specific system structures and technologies are provided for the purpose of illustration rather than limitation, so as to provide a thorough understanding of the embodiments of the present invention. However, it should be clear to those skilled in the art that the present invention can also be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, circuits, and methods are omitted to avoid unnecessary details that hinder the description of the present invention.

[0032] Figure 1 to Figure 2 The first embodiment of the ultrasonic transducer of the utility model is shown. The ultrasonic transducer can be used in beauty equipment to achieve different focusing depths and effectively solve the problem of the need for multiple focusing points of ultrasound, especially the need for focusing with different depths. The ultrasonic transducer has the advantages of simple and compact structure.

[0033] like Figure 1 and Figure 2 As shown, in this embodiment, the ultrasonic transducer may include a housing 10, at least two piezoelectric ceramic sheets and a fixing frame 30. The housing 10 can be used to install at least two piezoelectric ceramic sheets 2 and the fixing frame 30. The at least two piezoelectric ceramic sheets 2 are coaxially spaced in the housing 10, and are sequentially arranged at different horizontal planes from the outside to the inside, and are independent of each other, that is, the central axes of all piezoelectric ceramic sheets 2 can be overlapped, and the focal points of all piezoelectric ceramic sheets 2 can be on the same central axis. Each piezoelectric ceramic sheet 2 can be connected to a control circuit and a separate power amplifier; that is, each piezoelectric ceramic sheet 2 can be controlled separately. The fixing frame 30 can be one or more, and the fixing frame 30 is at least two. The at least two fixing frames 30 can be sequentially sleeved from the outside to the inside, and are coaxially arranged. Each fixing frame 30 can be used to install a piezoelectric ceramic sheet 2.

[0034] like Figure 3As shown, in this embodiment, the housing 10 may be cylindrical, and specifically, the housing 10 may be a through structure at both ends. A first sound-permeable hole 11 may be provided on the housing 10, and the first sound-permeable hole 11 is located at one end of the housing 10, and is used for the ultrasonic energy generated by the piezoelectric ceramic piece 2 to pass through. A cavity 12 may be defined on the inner side of the housing 10, and an opening 13 is provided at the end away from the first sound-permeable hole 11, and the opening 13 is connected to the cavity 12. A limit stop 14 is provided at one end of the housing 10, and the limit stop 14 is located at the end having the first sound-permeable hole 11, and can be provided in the first sound-permeable hole 11 along the circumference of the first sound-permeable hole 11, and is used for limiting the installation of the piezoelectric ceramic piece 2 to prevent the piezoelectric ceramic piece 2 installed thereon from falling out. At least one limiting groove 15 may be provided on the inner side wall of the housing 10. In some embodiments, the limiting groove 15 may be multiple, and the multiple limiting grooves 15 may be arranged at intervals along the axial direction of the housing 10, that is, an inner spiral structure may be formed inside the housing 10. The limiting groove 15 may be arranged along the circumference of the housing 10, and may be used for installing another fixing frame 30. The housing 10 is provided with a slot 16 on the end surface provided with the opening 13, and the slot 16 may be extended along the circumference of the housing 10.

[0035] In this embodiment, the ultrasonic transducer may include an end cap 20, which may be disposed on the housing 10 and may cover the opening 13. In this embodiment, the end cap 20 may be detachably connected to the housing 10. In this embodiment, the end cap 20 may include a cover body 21 and a nesting portion 22, and the cover body 21 may open and close the opening 13; the nesting portion 22 is protrudingly disposed on a side of the cover body 21 opposite to the opening 13, and may be substantially annular, and may be disposed along the circumference of the cover body 21. When the end cap 20 covers the opening 13, the nesting portion 22 may be embedded in the card slot 16, thereby enabling the end cap 20 to be sealed and assembled with the housing 10. In some embodiments, a glue injection hole 211 may be provided on the end cap 20, and the glue injection hole 211 may be used for injecting sealant into the cavity 12 after the components of the ultrasonic transducer are assembled.

[0036] In the present embodiment, the fixing frame 30 is arranged in the housing 10 and can be used for installing another piezoelectric ceramic sheet 2. The fixing frame 30 can be coaxially arranged with the housing 10 and can be detachably connected with the housing 10. In the present embodiment, the fixing frame 30 may include a cylinder 31 and at least two clamping parts 32. The cylinder 31 is coaxially arranged with the housing 10, and the cylinder 31 is a hollow structure with two ends penetrated. In some embodiments, a second sound-permeable hole 310 may be provided on the fixing frame 30, and the second sound-permeable hole 310 is formed in the cylinder 31. The second sound-permeable hole 310 may be arranged opposite to the first sound-permeable hole 11, and the two may be coaxially arranged. A limiting step 311 may be provided on the inner side of the cylinder 31, and the limiting step 311 may be provided along the circumference of the cylinder 31. The at least two clamping parts 32 are arranged at intervals along the circumference of the cylinder 31, and can be arranged on the outer circumference of the cylinder 31 and can extend toward the inner side wall of the housing 10. They can be hooks that can be inserted into the limiting groove 15, and then cooperate with the limiting groove 15 to limit the installation of the fixing frame 30. In some embodiments, a limiting hook 33 is provided on the fixing frame 30, and the limiting hook 33 can extend from the side wall of the cylinder 31 toward the side opposite to the first sound-permeable hole 11, and can be used to limit the installation of the piezoelectric ceramic sheet 2 installed on the fixing frame 30.

[0037] In some embodiments, the housing 10 and the fixing frame 30 are not limited to horizontal placement, and the angle can be adjusted as needed, thereby conditioning the ultrasonic incident angle. The incident angle can be horizontally 0° to 90°. The piezoelectric ceramic module can adjust the inner diameter size according to the focus spot requirements, and can also adjust the focus depth to 5 to 180 mm according to the focusing requirements.

[0038] In this embodiment, each of the at least two piezoelectric ceramic sheets 2 can be arched toward the side away from the first sound-permeable hole 11 (i.e., the side of the end cover 20), so that the ultrasonic waves generated by it can be focused on the central axis of the piezoelectric ceramic sheet 2. The cross-section of each piezoelectric ceramic sheet 2 can be roughly circular and have an arc. The radial dimensions of the at least two piezoelectric ceramic sheets 2 can be gradually reduced from the outside to the inside, which can facilitate installation and effectively utilize the internal space of the outermost fixing frame 30. In some embodiments, the piezoelectric ceramic sheet 2 can be plated, and the surface of the piezoelectric ceramic sheet 2 can be plated with a metal film by double-layer electroplating, and the thickness of the metal film can be 0.01 to 0.2 mm. Specifically, the piezoelectric ceramic sheet 2 can be silver-plated, and the silver-plating process is added between the ceramic and the waterproof adhesive layer, because silver plating can increase the stress on the surface of the piezoelectric ceramic sheet 2, and can effectively increase the reliability and durability of the product surface, further protect the service life of the piezoelectric ceramic sheet 2, reduce the degree of bubble enrichment, and reduce the energy loss caused by the interface during ultrasonic transmission. Applying a waterproof layer on the surface of the metal film (such as the silver surface) can effectively reduce the problem of loosening of the surface coating caused by vibration during ultrasonic operation. It can also prevent water and reduce the problem of bubble attachment caused by ultrasonic focusing. It can also prevent the loss of ultrasound during long-term immersion.

[0039] In this embodiment, at least two piezoelectric ceramic sheets 2 may include a first piezoelectric ceramic sheet 40 and a second piezoelectric ceramic sheet 50. It is understandable that the piezoelectric ceramic sheets 2 are not limited to two, and may also include a third piezoelectric ceramic sheet, a fourth piezoelectric ceramic sheet, etc. The first piezoelectric ceramic sheet 40 is disposed in the housing 10 and installed between the fixing frame 30 and the first sound-permeable hole 11. The second piezoelectric ceramic sheet 50 is installed on the fixing frame 30 and is coaxially arranged with the second sound-permeable hole 310. In this embodiment, except for the innermost piezoelectric ceramic sheet 2, the piezoelectric ceramic sheets 2 on the remaining fixing frames 30 have a through hole 41, and the through hole 41 can be coaxially arranged with another adjacent piezoelectric ceramic 2, that is, the second piezoelectric ceramic sheet 50 can cover the second sound-transmitting hole 310, and the first piezoelectric ceramic sheet 40 is provided with a through hole 41, which can be connected to the second sound-transmitting hole 310 and the first sound-transmitting hole 11, that is, the ultrasonic energy generated by the second piezoelectric ceramic sheet 50 can be emitted through the through hole 41 and the first sound-transmitting hole 310.

[0040] In the preparation of traditional ultrasonic transducers, the piezoelectric ceramic sheet 2 is usually pressed directly on the bottom of the shell in sequence, and then sealed and waterproofed by glue filling. In this embodiment, the internal spiral installation method can be selected during the installation of the piezoelectric ceramic sheet 2. This mode effectively reduces the close contact between the piezoelectric ceramic sheet 2 and the fixing frame 30, can effectively reduce the sound wave aftershocks caused by the gap, and reduce the loss caused by ultrasonic high-frequency operation.

[0041] In the present embodiment, the radial dimension of the first piezoelectric ceramic sheet 40 may be greater than the radial dimension of the second piezoelectric ceramic sheet 50. Specifically, the radial dimension of the first piezoelectric ceramic sheet 40 is 1 mm larger than the inner diameter of the housing 10, and is 1 mm smaller than the diameter of the opening 13 of the housing 10. In the present embodiment, the radial dimension of the first piezoelectric ceramic sheet 40 may be 10 mm to 200 mm. The aperture of the through hole 41 on the first piezoelectric ceramic sheet 40 may be 5 to 150 mm. The aperture of the second sound-permeable hole 310 on the fixing frame 30 may be greater than the aperture of the through hole 41, which is 1 to 3 mm larger than the aperture of the through hole 41.

[0042] In this embodiment, the height of the sealant filled in the cavity 12 may be higher than the height of the second piezoelectric ceramic sheet 50 . Specifically, the height of the sealant may be 3 to 10 mm higher than the highest point of the second piezoelectric ceramic sheet 50 .

[0043] In existing beauty equipment, multiple motors (dual motors, triple motors) are required to achieve the focusing depth. Since multiple motors will increase the complexity of the entire mechanism design and the failure rate and other problems, two or more piezoelectric ceramic sheets 2 are integrated to work in the axial direction, so that the two piezoelectric ceramic sheets 2 can generate two energy focuses at different horizontal positions at different depths of the skin when working. The two focuses are on the same axis, and the software and circuit control can be effectively implemented to adjust the focus position and depth, which can reduce the motion structure and motor mechanism, greatly reduce the overall structural framework, further increase the stability and reliability of the product and ultrasonic transducer, and reduce the overall cost of the product.

[0044] By using at least two piezoelectric ceramic sheets 2 that are coaxial and relatively independent, the impedance increase problem caused by each piezoelectric ceramic sheet 2 during the transmission process can be effectively reduced, the power consumption of the piezoelectric ceramic sheet 2 when generating the piezoelectric effect can be effectively reduced, the conduction of the single piezoelectric ceramic sheet 2 can be improved, and the actual service life of the piezoelectric ceramic sheet 2 can be improved. Since the two piezoelectric ceramic sheets 2 are controlled by separate power amplifiers and control circuits, the two piezoelectric ceramic sheets 2 do not affect each other during ultrasonic transmission. Therefore, it is possible to realize that the driving circuit sends a signal at the same time according to the needs to drive the piezoelectric effect of the ultrasonic piezoelectric ceramic chip to generate ultrasonic waves, and realize the simultaneous output of focal spots at different depths. In some embodiments, multiple piezoelectric ceramic sheets 2 of the ultrasonic transducer can also be connected to a control circuit, that is, the control circuit can also output multiple piezoelectric ceramic sheets 2 at the same frequency.

[0045] In this embodiment, a first buffer pad 60 is provided between the first piezoelectric ceramic sheet 40 and the limit stopper 14. The first buffer pad 60 may be annular. In some embodiments, the first buffer pad 60 may be a silicone pad. The first buffer pad 60 may be embedded in the limit stopper 14 and abut against the limit stopper 14 and the first piezoelectric ceramic sheet 40.

[0046] In this embodiment, a second buffer pad 70 can be arranged between the first piezoelectric ceramic sheet 40 and the fixing frame 30. The second buffer pad 70 can be annular. In some embodiments, the second buffer pad 70 can be a silicone pad, which is coaxially arranged with the first piezoelectric ceramic sheet 40 and the fixing frame 30, and elastically abuts against the first piezoelectric ceramic sheet 40 and the fixing frame 30.

[0047] In this embodiment, a third buffer pad 80 may be provided between the second piezoelectric ceramic sheet 50 and the fixing frame 30, and the third buffer pad 80 may be installed in the cylinder 31, located on the limiting step 311, and may elastically abut against the limiting step 311 and the second piezoelectric ceramic sheet 50. In this embodiment, the third buffer pad 80 may be a silicone pad, and may be annular, and may be coaxially arranged with the second sound-permeable hole 310.

[0048] The side effects of multiple reflections caused by the ultrasonic mechanical effect can be effectively reduced by providing the first buffer pad 60, the second buffer pad 70 and the third buffer pad 80. The above buffer pads are not only used in dual-aperture transducers, but also can be used in dual-ring piezoelectric ceramics, boat-shaped piezoelectric ceramics, and petal-shaped piezoelectric ceramics. Unique and ingenious damping devices can effectively reduce the vibration loss between each piezoelectric ceramic sheet 2 and effectively improve the efficiency of ultrasonic focusing vibration.

[0049] Figure 4 and Figure 5 The second embodiment of the utility model is shown, which differs from the first embodiment in that the slot 16 of the housing 10 can be omitted, the nesting portion 22 of the end cover 20 can be omitted, and the second buffer pad 70 can be omitted. The clamping portion 32 of the fixing frame 30 can be substantially straight and can extend radially outwardly along the cylinder 31, and the limiting hook 33 can be omitted.

[0050] It can be understood that the above embodiments only express the preferred implementation methods of the utility model, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the patent scope of the utility model. It should be pointed out that, for ordinary technicians in this field, without departing from the concept of the utility model, the above-mentioned technical features can be freely combined, and several deformations and improvements can be made, which all belong to the protection scope of the utility model. Therefore, all equivalent changes and modifications made to the scope of the claims of the utility model should belong to the scope covered by the claims of the utility model.

Claims

1. An ultrasonic transducer, characterized in that: include: The housing (10) is cylindrical and has a first sound-transmitting hole (11) at one end; At least two piezoelectric ceramic sheets (2) are coaxially arranged in the housing (10) at intervals, and are arranged in sequence from the outside to the inside at different horizontal planes and are independent of each other; each piezoelectric ceramic sheet (2) is coaxially arranged with the first sound-permeable hole (11), and the ultrasonic energy generated by it is transmitted through the first sound-permeable hole (11), and the focusing points of all the piezoelectric ceramic sheets (2) are on the same central axis, and except for the innermost piezoelectric ceramic sheet (2), the remaining piezoelectric ceramic sheets (2) have a through hole (41); the through hole (41) is coaxially arranged with another adjacent piezoelectric ceramic sheet (2) for ultrasonic energy to pass through.

2. The ultrasonic transducer according to claim 1, characterized in that: The piezoelectric ceramic sheet (2) is arched toward a side away from the first sound-permeable hole (11), so that its ultrasonic energy is focused on the central axis of the piezoelectric ceramic sheet (2).

3. The ultrasonic transducer according to claim 1, characterized in that: The radial dimensions of at least two of the piezoelectric ceramic sheets (2) gradually decrease from the outside to the inside.

4. The ultrasonic transducer according to claim 1, characterized in that: The ultrasonic transducer also includes: A fixing frame (30) is arranged in the housing (10) and is provided with a second sound-transmitting hole (310) arranged opposite to the first sound-transmitting hole (11); At least two piezoelectric ceramic sheets (2), comprising: A first piezoelectric ceramic sheet (40) is disposed in the housing (10) and installed between the fixing frame (30) and the first sound-transmitting hole (11); the first piezoelectric ceramic sheet (40) is provided with a through hole (41) communicating with the second sound-transmitting hole (310) and the first sound-transmitting hole (11); The second piezoelectric ceramic sheet (50) is mounted on the fixing frame (30) and is coaxially arranged with the second sound-permeable hole (310).

5. The ultrasonic transducer according to claim 4, characterized in that: A limit stop (14) is provided at one end of the housing (10); the limit stop (14) is arranged in the first sound-permeable hole (11) along the circumference of the first sound-permeable hole (11) and is used for limiting the installation of the first piezoelectric ceramic sheet (40).

6. The ultrasonic transducer according to claim 5, characterized in that: A first buffer pad (60) is provided between the first piezoelectric ceramic sheet (40) and the position limiting stop platform (14).

7. The ultrasonic transducer according to claim 4, characterized in that: A second buffer pad (70) is provided between the first piezoelectric ceramic sheet (40) and the fixing frame (30).

8. The ultrasonic transducer according to claim 4, characterized in that: The inner wall of the housing (10) is provided with at least one limiting groove (15) for limiting the installation of the fixing frame (30); The fixing frame (30) comprises a cylinder (31) and at least two clamping parts (32) arranged on the outer periphery of the cylinder (31); the cylinder (31) is hollow to form the second sound-transmitting hole (310); The clamping portion (32) extends toward the inner side wall of the housing (10) to be clamped into the limiting groove (15).

9. The ultrasonic transducer according to claim 4, characterized in that: The fixing frame (30) is provided with a limit hook (33), and the limit hook (33) extends toward a side opposite to the first sound-permeable hole (11), and is used for limiting the installation of the second piezoelectric ceramic sheet (50).

10. The ultrasonic transducer according to claim 4, characterized in that: A third buffer pad (80) is provided between the second piezoelectric ceramic sheet (50) and the fixing frame (30).

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