A small medical transducer

Abstract

This invention belongs to the field of transducer technology and discloses a small medical transducer. The small medical transducer includes a ceramic stack and a lead-out assembly. The ceramic stack includes multiple annular piezoelectric ceramic sheets. The lead-out assembly includes a conductive lead, one end of which is electrically connected to the polarization surfaces of the multiple piezoelectric ceramic sheets and disposed within the hollow cavity of the ceramic stack. The other end of the conductive lead extends along the axial direction of the ceramic stack and is electrically connected to an external signal generating device. The small medical transducer of this invention, with its conductive lead disposed within the hollow cavity of the ceramic stack, compresses the overall volume of the transducer, achieving miniaturization, expanding its application range, and increasing its usability. The ceramic stack provides a certain degree of protection for the conductive lead, and the built-in conductive lead does not interfere with the transducer's vibration, improving the transducer's operational reliability.

Description

Technical Field

[0001] This invention relates to the field of transducer technology, and more particularly to a small medical transducer. Background Technology

[0002] A transducer is an energy conversion device that converts electrical energy into acoustic energy and vice versa. It has a wide range of applications in industry, agriculture, transportation, daily life, medicine, and the military. For sandwich transducers commonly used in the medical field (e.g., ultrasonic cutting and hemostasis systems), miniaturization is crucial for insertion into the abdominal cavity. However, existing sandwich transducers typically use electrode plates extended from the outer wall of the transducer to achieve electrical connection with the piezoelectric ceramic. This connection method occupies a significant amount of space, hindering miniaturization and limiting the transducer's application range and usage scenarios. Furthermore, the electrode plates lack protection and are prone to breakage. Additionally, the electrode plates can interfere with the transducer's vibration, reducing its reliability. Summary of the Invention

[0003] The purpose of this invention is to provide a small medical transducer that allows electrodes to be led out from inside the transducer, thus ensuring the miniaturization of the transducer, expanding its applicability, and improving its operational reliability.

[0004] To achieve this objective, the present invention adopts the following technical solution:

[0005] A small medical transducer is provided, comprising:

[0006] Ceramic stack, comprising multiple ring-shaped piezoelectric ceramic sheets;

[0007] The lead-out component includes a conductive lead-out element, one end of which is electrically connected to the polarization surfaces of a plurality of piezoelectric ceramic sheets and disposed in the hollow cavity of the ceramic stack. The other end of the conductive lead-out element extends out along the axial direction of the ceramic stack and is electrically connected to an external signal generating device.

[0008] As a preferred structure of the present invention, the medical miniature transducer further includes a front cover and a rear cover arranged coaxially. The front cover has a mounting post extending rearward along the axis and having a hollow inner cavity. The mounting post is provided with an external thread portion and an external smooth portion adjacent to the external thread portion. The external thread portion and the external smooth portion are provided with a placement groove communicating with the hollow inner cavity of the mounting post. The ceramic stack is fitted onto the external smooth portion. The rear cover is assembled via the external thread portion and pushes against the ceramic stack onto the front cover. The conductive lead-out passes through the hollow inner cavity of the mounting post and is electrically connected to a plurality of the piezoelectric ceramic sheets.

[0009] As a preferred embodiment of the present invention, the medical miniature transducer further includes a housing, and the housing and the front cover are assembled by threads or anchors.

[0010] As a preferred structure of the present invention, the polarization direction of the piezoelectric ceramic sheet is axially polarized, and the lead-out assembly further includes a plurality of electrode rings, with one piezoelectric ceramic sheet disposed between each two adjacent electrode rings. Each electrode ring has an electrode extending through the mounting groove into the hollow cavity of the mounting post. The electrode is L-shaped and is connected to the corresponding conductive lead-out member by conductive adhesive or welding according to its polarity.

[0011] As a preferred structure of the present invention, the polarization directions of each pair of adjacent piezoelectric ceramic sheets are opposite, the conductive lead includes a first lead or a second lead disposed opposite to each other, the electrodes of adjacent electrode rings are respectively connected to the first lead and the second lead according to their polarity, and an alternating signal is applied to the first lead and the second lead.

[0012] As a preferred structure of the present invention, the polarization direction of the piezoelectric ceramic sheet is radially polarized, the positive polarization surface and the negative polarization surface of the piezoelectric ceramic sheet are respectively located on the inner ring surface or the outer ring surface of the piezoelectric ceramic sheet, the conductive lead is attached to and abuts the inner ring surface, and the housing is electrically connected to the outer ring surface.

[0013] As a preferred structure of the present invention, the conductive lead-out member includes a conductive part and a lead-out part. The conductive part passes through the mounting groove and then fits against the polarized inner annular surface of the piezoelectric ceramic sheet. The lead-out part extends rearward from the conductive part and is accommodated in the hollow inner cavity of the mounting post.

[0014] As a preferred structure of the present invention, the conductive part is provided with a plurality of conductive protrusions, the conductive protrusions being able to abut against the polarized inner ring surface of the piezoelectric ceramic sheet, and the outer surface of the conductive protrusions being provided with a wear-resistant conductive coating, the wear-resistant conductive coating material including aluminum or gold or conductive epoxy resin or graphite.

[0015] In a preferred embodiment of the present invention, the polarization directions of two adjacent piezoelectric ceramic sheets are opposite. The conductive lead-out includes a first conductive element and a second conductive element disposed opposite to each other. The conductive protrusions of the first conductive element and the conductive protrusions of the second conductive element are offset according to their polarities. The conductive protrusions of the first conductive element are used to abut against the positive polarization surface of the piezoelectric ceramic sheet, and the conductive protrusions of the second conductive element are used to abut against the negative polarization surface of the piezoelectric ceramic sheet. The signal applied to the first conductive element and the signal applied to the second conductive element are two alternating signals with opposite phases.

[0016] As a preferred structure of the present invention, the polarization directions of two adjacent piezoelectric ceramic sheets are the same, the multiple conductive protrusions of the conductive lead-out member abut against the inner ring surface of the multiple piezoelectric ceramic sheets in sequence, the housing is electrically connected to the outer ring surface, and the signal applied to the conductive lead-out member is an alternating signal.

[0017] The beneficial effects of this invention are:

[0018] The medical miniature transducer provided by this invention comprises a ceramic stack including multiple annular piezoelectric ceramic sheets, which are stacked sequentially. One end of a conductive lead is electrically connected to the multiple piezoelectric ceramic sheets and is disposed within the hollow cavity of the ceramic stack. The other end of the conductive lead extends along the axial direction of the ceramic stack and is electrically connected to an external signal generating device. The conductive lead can be a metal sheet or metal wire, or other structures with conductive properties. Through the lead-out of the conductive lead, the piezoelectric ceramic sheets are electrically connected to the external signal generating device, thereby generating vibration of the ceramic stack. The conductive lead is disposed within the hollow cavity of the ceramic stack, avoiding the excessive space occupied by placing it outside the ceramic stack, thus compressing the overall volume of the medical miniature transducer, achieving miniaturization, expanding its application range, and increasing its usability. Electrodes placed outside the ceramic stack are prone to breakage and can interfere with the vibration of the medical miniature transducer. The conductive leads are placed inside the hollow ceramic stack to prevent them from breaking easily. Furthermore, the built-in conductive leads do not interfere with the vibration of the medical miniature transducer, thereby improving the operational reliability of the medical miniature transducer. Attached Figure Description

[0019] Figure 1 This is a structural cross-sectional view of the medical miniature transducer provided in Embodiment 1 of the present invention;

[0020] Figure 2 This is a schematic diagram of the electrode ring, mounting post, and lead-out assembly for ceramic stacking provided in Embodiment 1 of the present invention;

[0021] Figure 3 This is a schematic diagram of the polarization surface of the piezoelectric ceramic sheet provided in Embodiment 1 of the present invention;

[0022] Figure 4 This is a polarized cross-sectional view of the piezoelectric ceramic sheet provided in Embodiment 1 of the present invention;

[0023] Figure 5 This is a schematic diagram of the structure of the electrode ring connected to the conductive lead provided in Embodiment 1 of the present invention. Figure 1 ;

[0024] Figure 6 This is a schematic diagram of the structure of the electrode ring connected to the conductive lead provided in Embodiment 1 of the present invention. Figure 2 ;

[0025] Figure 7 This is a schematic diagram of an alternating signal introduced into a piezoelectric ceramic sheet according to Embodiment 1 of the present invention;

[0026] Figure 8 This is a structural cross-sectional view of the small medical transducer provided in Embodiment 2 of the present invention;

[0027] Figure 9 This is a schematic diagram of the polarization surface of the piezoelectric ceramic sheet provided in Embodiment 2 of the present invention;

[0028] Figure 10 This is a cross-sectional view of the front cover threaded connection housing in Embodiment 2 of the present invention. Figure 1 ;

[0029] Figure 11 This is a cross-sectional view of the front cover anchor bolt connection shell of Embodiment 2 of the present invention. Figure 2 ;

[0030] Figure 12 This is a schematic diagram of the structure of the conductive lead-out component provided in Embodiment 2 of the present invention;

[0031] Figure 13 This is a polarized cross-section of the piezoelectric ceramic sheet provided in Embodiment 2 of the present invention. Figure 1 ;

[0032] Figure 14 This is a polarized cross-section of the piezoelectric ceramic sheet provided in Embodiment 2 of the present invention. Figure 2 ;

[0033] Figure 15 This is a schematic diagram of introducing an alternating signal into a piezoelectric ceramic sheet according to Embodiment 2 of the present invention. Figure 1 ;

[0034] Figure 16 This is a schematic diagram of introducing an alternating signal into a piezoelectric ceramic sheet according to Embodiment 2 of the present invention. Figure 2 ;

[0035] Figure 17 This is a schematic diagram of the installation of the conductive lead-out component provided in Embodiment 2 of the present invention. Figure 1 ;

[0036] Figure 18 This is a schematic diagram of the installation of the conductive lead-out component provided in Embodiment 2 of the present invention. Figure 2 .

[0037] In the picture:

[0038] 1. Ceramic stack; 11. Piezoelectric ceramic sheet; 12. Front cover; 121. Mounting post; 1211. External threaded part; 1212. External smooth part; 1213. Reservoir; 13. Rear cover; 2. Lead-out assembly; 21. Conductive lead-out element; 211. First lead-out element; 212. Second lead-out element; 213. Conductive part; 214. Lead-out part; 215. Conductive protrusion; 216. First conductive element; 217. Second conductive element; 22. Electrode ring; 221. Electrode; 23. Lead wire; 3. Housing;

[0039] 100. Press the buckle. Detailed Implementation

[0040] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, and not all of the structures.

[0041] In the description of this invention, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0042] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0043] In the description of this embodiment, the terms "upper," "lower," "left," and "right," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention. In addition, the terms "first" and "second" are used only for distinction in description and have no special meaning.

[0044] Example 1

[0045] like Figures 1-7 As shown, Embodiment 1 of the present invention provides a small medical transducer, which includes a ceramic stack 1 and a lead-out assembly 2. The ceramic stack 1 includes multiple annular piezoelectric ceramic sheets 11, which are stacked sequentially to form the ceramic stack 1. The polarization direction of the piezoelectric ceramic sheets 11 is radial or axial polarization. A high voltage is applied to both sides of the PZT ceramic (lead zirconate titanate) to form an electric field, which polarizes the piezoelectric ceramic sheets 11. When a voltage is applied to the radially or axially polarized piezoelectric ceramic sheets 11, the piezoelectric ceramic sheets 11 will generate axial expansion and contraction vibrations due to the inverse piezoelectric effect of the piezoelectric body expanding and contracting in the vertical or horizontal direction. The lead-out assembly 2 includes a conductive lead 21. One end of the conductive lead 21 is electrically connected to the polarization surface of the multiple piezoelectric ceramic sheets 11 and is disposed in the hollow cavity of the ceramic stack 1. The other end of the conductive lead 21 extends out along the axial direction of the ceramic stack 1 and is electrically connected to an external signal generating device. The conductive lead-out 21 can be a metal sheet or metal wire, or other structure with conductive properties. Through the lead-out 21, the piezoelectric ceramic sheet 11 is electrically connected to an external signal generating device, thereby generating vibration of the ceramic stack 1. The conductive lead-out 21 is disposed within the hollow cavity of the ceramic stack 1, avoiding the need for an external placement that would occupy excessive space. This reduces the overall size of the medical miniature transducer, enabling miniaturization, expanding its application range, and increasing its usability. The ceramic stack 1 provides some protection for the conductive lead-out 21, preventing breakage. Furthermore, the built-in conductive lead-out 21 does not interfere with the vibration of the medical miniature transducer, thus improving its operational reliability.

[0046] As a preferred option, such as Figure 2As shown, the medical miniature transducer also includes a front cover 12 and a rear cover 13 coaxially arranged. The front cover 12 has a mounting post 121 extending rearward along the axis and having a hollow inner cavity. The mounting post 121 is provided with an external threaded portion 1211 and an external smooth portion 1212 adjacent to the external threaded portion 1211. The external threaded portion 1211 and the external smooth portion 1212 are provided with a placement groove 1213 communicating with the hollow inner cavity of the mounting post 121. The ceramic stack 1 is fitted onto the external smooth portion 1212. The rear cover 13 is assembled via the external threaded portion 1211 and pushed against the ceramic stack 1 to the front cover 12. That is, multiple piezoelectric ceramic sheets 11 are fitted onto the mounting post 121, and the two ends of the ceramic stack 1 abut against the front cover 12 and the rear cover 13 respectively, thereby fixing the multiple piezoelectric ceramic sheets 11. The conductive lead 21 passes through the hollow inner cavity of the mounting post 121 and is electrically connected to the multiple piezoelectric ceramic sheets 11. The hollow inner cavity creates a hollow structure for the mounting post 121, allowing one end of the conductive lead 21 to extend out. It is understood that multiple piezoelectric ceramic sheets 11 are fitted around the outer smooth portion 1212 to form a ceramic stack 1. The conductive lead 21 passes through the mounting groove 1213 provided in the outer smooth portion 1212 and the external thread portion 1211, allowing the free end of the conductive lead 21 to extend within the hollow inner cavity. Because the mounting groove 1213 connects to the hollow inner cavity, one end of the conductive lead 21 can pass through the mounting groove 1213 and extend within the hollow inner cavity, thus changing the space occupied by the lead wire and not occupying space outside the ceramic stack 1, thereby reducing the size of the small medical transducer. The conductive lead 21 extends from the mounting groove 1213 into the hollow inner cavity until it reaches the outside of the small medical transducer, thereby electrically connecting to an external signal generating device. For ease of manufacturing, the mounting post 121 can be integrally formed with the front cover 12.

[0047] More specifically, the medical miniature transducer also includes a housing 3, such as Figure 1 As shown, the housing 3 and the front cover 12 are assembled by threads or anchor bolts (see reference). Figure 11 (As shown); then, add threadlocker or other adhesives to further increase the reliability and sealing of the connection. Besides threaded connections, the housing 3 and the front cover 12 can also be connected using multiple anchor bolts, such as... Figure 11 As shown, the anchor bolts pass through the shell 3 along its wall thickness and connect to the front cover 12. At least three anchor bolts are required for stable support, and these anchor bolts are evenly distributed circumferentially around the shell 3. For example, the number of anchor bolts can be four, five, or six. The shell 3 serves as a conductive structure, ensuring the normal operation of the ceramic stack 1. Compared to flange connections, threaded and anchor bolt connections significantly reduce space requirements, eliminating the need for connecting flanges and further reducing the size of the small medical transducer.

[0048] Specifically, when the polarization direction of the piezoelectric ceramic sheet 11 is axially polarized, the positive polarization surface and the negative polarization surface of the piezoelectric ceramic sheet 11 are respectively disposed at both ends of the piezoelectric ceramic sheet 11 (D33 type piezoelectric ceramic), such as... Figure 3 As shown in the figure, the shaded area represents the polarization surface; the positive and negative polarization surfaces of the polarized piezoelectric ceramic sheet 11 are represented by + and -, respectively, as shown in the figure. Figure 4 As shown. The lead-out assembly 2 also includes multiple electrode rings 22, which are respectively disposed between two adjacent piezoelectric ceramic sheets 11. Each electrode ring 22 has an electrode 221 extending towards the center, which extends through the mounting groove 1213 into the hollow cavity of the mounting post 121. Figure 5 As shown, electrode 221 is connected to conductive lead-out component 21. Since electrode ring 22 cannot be directly processed into a long, bent structure, it can be divided into a single circular ring and a long strip for connection. Electrode 221 is led out by two metal springs. The lead-out end of electrode 221 is roughly L-shaped or arc-shaped, and is connected to the corresponding conductive lead-out component 21 by conductive adhesive or welding according to polarity. Specifically, electrode 221 and conductive lead-out component 21 can be fixedly connected by conductive adhesive bonding or welding, which simplifies the processing of electrode ring 22. Furthermore, conductive lead-out component 21 can be a superimposed connection of multiple conductive metal sheets: during processing, each electrode 221 of electrode ring 22 is connected to a conductive metal sheet. Multiple electrode rings 22 are evenly arranged among multiple piezoelectric ceramic sheets 11, and the conductive metal sheets of each electrode ring 22 are superimposed to form a conductive lead-out component 21 extending along the axial direction.

[0049] For axially polarized piezoelectric ceramic sheets 11, to achieve a larger vibration effect in the medical miniature transducer, adjacent piezoelectric ceramic sheets 11 need to have the same compression or expansion state; therefore, adjacent piezoelectric ceramic sheets 11 need to have opposite polarization directions. In this case, such as... Figure 6 As shown, the conductive lead-out element 21 includes a first lead-out element 211 and a second lead-out element 212 disposed opposite to each other. The electrodes 221 of adjacent electrode rings 22 are respectively connected to the first lead-out element 211 or the second lead-out element 212 according to their polarity. An alternating signal is applied between the first lead-out element 211 and the second lead-out element 212. In this embodiment of the invention, the first lead-out element 211 is used to lead out the positive electrode of the positive polarization surface, and the second lead-out element 212 is used to lead out the negative electrode of the negative polarization surface, such as... Figure 7 As shown, GND is the grounding wire of the first lead 211, and VCC is the power supply voltage connected to the second lead 212.

[0050] Example 2

[0051] like Figures 8-18As shown, Embodiment 2 of the present invention provides a small medical transducer having the same ceramic stack 1 and lead-out component 2 as Embodiment 1. The ceramic stack 1 includes multiple annular piezoelectric ceramic sheets 11, which are sequentially stacked to form the ceramic stack 1, as shown. Figure 8 As shown, the conductive lead-out element 21 is disposed within the hollow cavity of the ceramic stack 1 and extends outwards, avoiding its placement on the outside of the ceramic stack 1 and thus occupying excessive space, thereby compressing the overall volume of the medical miniature transducer and achieving miniaturization of the medical miniature transducer. The difference in Embodiment 2 of the present invention is that the polarization direction of the piezoelectric ceramic sheet 11 is radial polarization, and the positive polarization surface and negative polarization surface of the piezoelectric ceramic sheet 11 are respectively disposed on the inner ring surface or the outer ring surface of the piezoelectric ceramic sheet 11, such as... Figure 9 As shown. The conductive lead-out component 21 is attached to and abuts against the inner ring surface, and the housing 3 is electrically connected to the outer ring surface, thereby leading out the electrodes of the inner and outer ring surfaces respectively. The housing 3 can be a metal shell, and is led out to the ground wire through the ground wire terminal; a small amount of conductive adhesive can be used for electrical connection between the piezoelectric ceramic sheets 11 and between the piezoelectric ceramic sheets 11 and the housing 3.

[0052] As a preferred embodiment, the conductive lead-out member 21 includes a conductive portion 213 and a lead-out portion 214 that are interconnected, such as Figure 12 As shown, the conductive part 213 is the large-diameter end, and the lead-out part 214 is the small-diameter end. The conductive part 213 passes through the mounting groove 1213 and then fits against the inner ring surface of the piezoelectric ceramic sheet 11, while the lead-out part 214 is housed within the hollow cavity. In the second embodiment of the present invention, the conductive lead-out part 21 can be made of a metal spring sheet, which has conductivity and a certain degree of elasticity. Since the lead-out part 214 at the small-diameter end is confined within the hollow cavity of the mounting post 121, it is ensured that the conductive part 213 at the large-diameter end can fit tightly against the inner ring surface.

[0053] Furthermore, the conductive lead 21 is provided with multiple conductive protrusions 215, which can abut against the polarized inner ring surface of the piezoelectric ceramic sheet 11, improving the conductivity of the conductive lead 21 and preventing the conductive lead 21 from shifting position. The outer surface of the conductive protrusions 215 can be plated with a wear-resistant conductive coating, and the material of the wear-resistant conductive coating includes, but is not limited to, aluminum film, gold plating, conductive epoxy resin, or graphite.

[0054] Specifically, for the radially polarized piezoelectric ceramic sheet 11 in this embodiment 2, the polarization directions of two adjacent piezoelectric ceramic sheets 11 can be opposite, such as... Figure 14 As shown; the polarization directions of two adjacent piezoelectric ceramic sheets 11 can also be the same, such as Figure 13As shown, both can achieve a relatively large vibration effect in small medical transducers. The polarized piezoelectric ceramic sheet 11 has an electrode surface, with the positive polarization surface and negative polarization surface represented by + and -, respectively. The edges of the piezoelectric ceramic sheet 11 are chamfered to prevent short circuits from occurring at the contact edges of adjacent piezoelectric ceramic sheets 11 when they have different polarities.

[0055] When the polarization directions of two adjacent piezoelectric ceramic sheets 11 are opposite, the conductive lead-out member 21 includes a first conductive member 216 and a second conductive member 217 arranged opposite to each other. The conductive protrusions 215 of the first conductive member 216 and the conductive protrusions 215 of the second conductive member 217 are arranged alternately according to polarity. The conductive protrusions 215 of the first conductive member 216 are used to abut against the positive polarization surface of the piezoelectric ceramic sheet 11, and the conductive protrusions 215 of the second conductive member 217 are used to abut against the negative polarization surface of the piezoelectric ceramic sheet 11. Since the polarization directions of two adjacent piezoelectric ceramic sheets 11 are opposite, their inner annular surfaces are the positive polarization surface and the negative polarization surface, respectively. The positive polarization surface and the negative polarization surface are led out through the first conductive member 216 and the second conductive member 217, respectively. The alternating current applied to the first conductive member 216 and the alternating current applied to the second conductive member 217 are out of phase, thereby ensuring that the compression state or expansion state of the adjacent piezoelectric ceramic sheets 11 is consistent. For this radially polarized piezoelectric ceramic sheet 11 with opposite polarization directions, three leads 23 are needed to realize two alternating signals. Two leads 23 are connected to the first conductive element 216 and the second conductive element 217, respectively, and the third lead 23 is connected to the housing 3, as shown below. Figure 16 As shown, GND is the grounding wire of the housing 3, and VCC+ and VCC- are respectively connected to the power supply voltage of the first conductive element 216 and the alternating signal of the second conductive element 217.

[0056] Furthermore, the first conductive element 216 and the second conductive element 217 can be metal springs with identical shapes. The lead-out portions 214 of the first conductive element 216 and the second conductive element 217 are arranged opposite each other, as are the conductive portions 213 of the first conductive element 216 and the second conductive element 217. When installing the conductive lead-out element 21, the elasticity of the conductive lead-out element 21 can be utilized. By pressing the buckle 100, one end of the lead-out portion 214 is gathered, and one end of the conductive portion 213 is deformed in the axial direction, facilitating passage through the hollow cavity of the mounting post 121. Figure 17 As shown; then release the pressing buckle 100, and one end of the conductive part 213 will recover its elastic deformation, thus tightly fitting and abutting against the inner ring surface, as shown. Figure 18 As shown. The structure of the snap fastener 100 is prior art in this field, and will not be described in detail here.

[0057] Similarly, it can be seen that for medical miniature transducers with the same polarization direction for two adjacent piezoelectric ceramic sheets 11, the electrodes on adjacent inner annular surfaces are identical. Therefore, only one conductive lead-out element 21 is needed, and the multiple conductive protrusions 215 of the conductive lead-out element 21 sequentially abut against multiple piezoelectric ceramic sheets 11. For such radially polarized piezoelectric ceramic sheets 11 with the same polarization direction, two leads 23 are required to achieve one alternating signal. One lead 23 is connected to the conductive lead-out element 21, and the other lead 23 is connected to the housing 3, as shown below. Figure 15 As shown, GND is the grounding wire of the housing 3, and VCC is the power supply voltage connected to the conductive lead 21. That is, corresponding to the application of D31 type piezoelectric ceramics in medical miniature transducers, when adjacent piezoelectric ceramic sheets 11 have the same polarization direction, two leads 23 are needed to lead out the electrodes. By applying an alternating signal to the two leads 23, the compression / expansion state of the two adjacent piezoelectric ceramic sheets 11 can be made consistent.

[0058] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art will be able to make various obvious changes, readjustments, and substitutions without departing from the scope of protection of the present invention. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A small medical transducer, characterized in that, include: The ceramic stack (1) includes multiple annular piezoelectric ceramic sheets (11). The lead-out component (2) includes a conductive lead-out element (21). One end of the conductive lead-out element (21) is electrically connected to the polarization surfaces of a plurality of piezoelectric ceramic sheets (11) and is disposed in the hollow cavity of the ceramic stack (1). The other end of the conductive lead-out element (21) extends out along the axial direction of the ceramic stack (1) and is electrically connected to an external signal generating device. The medical miniature transducer also includes a front cover (12) and a rear cover (13) arranged coaxially. The front cover (12) has a mounting post (121) extending rearward along the axis and having a hollow inner cavity. The mounting post (121) is provided with an external threaded portion (1211) and an external smooth portion (1212) adjacent to the external threaded portion (1211). The external threaded portion (1211) and the external smooth portion (1212) are provided with a placement groove (1213) communicating with the hollow inner cavity of the mounting post (121). The ceramic stack (1) is fitted onto the external smooth portion (1212). The rear cover (13) is assembled through the external threaded portion (1211) and pushed against the ceramic stack (1) to the front cover (12). The conductive lead (21) passes through the hollow inner cavity of the mounting post (121) and is electrically connected to a plurality of piezoelectric ceramic sheets (11).

2. The medical miniature transducer according to claim 1, characterized in that, The medical miniature transducer also includes a housing (3), which and the front cover (12) are assembled by threads or anchors.

3. The medical miniature transducer according to claim 1, characterized in that, The piezoelectric ceramic sheet (11) is axially polarized. The lead-out assembly (2) also includes a plurality of electrode rings (22). A piezoelectric ceramic sheet (11) is disposed between each two adjacent electrode rings (22). Each electrode ring (22) has an electrode (221) extending through the mounting groove (1213) into the hollow cavity of the mounting post (121). The electrode (221) is L-shaped and is connected to the corresponding conductive lead-out (21) by conductive adhesive or welding according to polarity.

4. The medical miniature transducer according to claim 3, characterized in that, The polarization directions of each pair of adjacent piezoelectric ceramic sheets (11) are opposite. The conductive lead (21) includes a first lead (211) and a second lead (212) arranged opposite to each other. The electrodes (221) of adjacent electrode ring sheets (22) are respectively connected to the first lead (211) or the second lead (212) according to their polarity. An alternating signal is applied to the first lead (211) and the second lead (212).

5. The medical miniature transducer according to claim 2, characterized in that, The polarization direction of the piezoelectric ceramic sheet (11) is radial polarization. The positive polarization surface and the negative polarization surface of the piezoelectric ceramic sheet (11) are located on the inner ring surface or the outer ring surface of the piezoelectric ceramic sheet (11), respectively. The conductive lead-out member (21) is attached to and abuts the inner ring surface, and the housing (3) is electrically connected to the outer ring surface.

6. The medical miniature transducer according to claim 5, characterized in that, The conductive lead-out member (21) includes a conductive part (213) and a lead-out part (214). The conductive part (213) passes through the mounting groove (1213) and then fits against the polarized inner ring surface of the piezoelectric ceramic sheet (11). The lead-out part (214) extends rearward from the conductive part (213) and is accommodated in the hollow cavity of the mounting post (121).

7. The medical miniature transducer according to claim 6, characterized in that, The conductive part (213) is provided with a plurality of conductive protrusions (215), the conductive protrusions (215) can abut against the polarized inner ring surface of the piezoelectric ceramic sheet (11), and the outer surface of the conductive protrusions (215) is provided with a wear-resistant conductive coating, the material of the wear-resistant conductive coating including aluminum or gold or conductive epoxy resin or graphite.

8. The medical miniature transducer according to claim 7, characterized in that, The polarization directions of two adjacent piezoelectric ceramic sheets (11) are opposite. The conductive lead-out member (21) includes a first conductive member (216) and a second conductive member (217) arranged opposite to each other. The conductive protrusions (215) of the first conductive member (216) and the conductive protrusions (215) of the second conductive member (217) are arranged in a staggered manner according to polarity. The conductive protrusions (215) of the first conductive member (216) are used to abut against the positive polarization surface of the piezoelectric ceramic sheet (11), and the conductive protrusions (215) of the second conductive member (217) are used to abut against the negative polarization surface of the piezoelectric ceramic sheet (11). The signal applied to the first conductive member (216) and the signal applied to the second conductive member (217) are two alternating signals and the phases of the two alternating signals are opposite.

9. The medical miniature transducer according to claim 7, characterized in that, The polarization directions of two adjacent piezoelectric ceramic sheets (11) are the same. The multiple conductive protrusions (215) of the conductive lead-out member (21) abut against the inner ring surface of the multiple piezoelectric ceramic sheets (11) in sequence. The housing (3) is electrically connected to the outer ring surface. The signal applied to the conductive lead-out member (21) is an alternating signal.

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