Ultrasonic transducer, ultrasonic metering device and ultrasonic gas meter

Abstract

The utility model provides an ultrasonic transducer, an ultrasonic metering device and an ultrasonic gas meter. The ultrasonic transducer comprises a shell, a matching layer, a metal coating and piezoelectric ceramic. The matching layer is arranged in the shell and connected with the shell. The metal coating is formed on the matching layer. The piezoelectric ceramic is arranged in the shell and located on the side, away from the matching layer, of the metal coating, the piezoelectric ceramic comprises a plurality of vibration units, and the multiple vibration units are electrically connected with the metal coating. The risk that the signal strength is weakened in the transmission process of the ultrasonic waves can be reduced.

Description

TECHNICAL FIELD

[0001] Embodiments of the present application relate to the technical field of ultrasonic device, in particular to an ultrasonic transducer, an ultrasonic metering device and an ultrasonic gas meter. BACKGROUND

[0002] The ultrasonic gas meter is a new type of gas meter, which includes two ultrasonic transducers. The two ultrasonic transducers are used to measure the flow rate of fluid in the metering pipeline per unit time. The ultrasonic transducer generally includes a shell, a piezoelectric ceramic and a matching layer arranged in the shell. The piezoelectric ceramic also has a positive electrode and a negative electrode. The positive electrode and the negative electrode are connected to a power supply to provide power for the piezoelectric ceramic.

[0003] In order to improve the sensitivity and high-speed response of the ultrasonic transducer, a groove is usually cut on the piezoelectric ceramic to divide the piezoelectric ceramic into several different vibration sources. Therefore, the material of the shell needs to be changed so that the shell has conductivity, and then the several different vibration sources are connected together.

[0004] However, the ultrasonic signal generated by the above ultrasonic transducer is attenuated during transmission, thereby reducing the sensitivity and measurement accuracy of the ultrasonic gas meter. CONTENT OF THE INVENTION

[0005] In view of the above problems, embodiments of the present application provide an ultrasonic transducer, an ultrasonic metering device and an ultrasonic gas meter, which can reduce the risk of weakening the signal strength of ultrasonic waves during transmission.

[0006] In order to achieve the above purpose, embodiments of the present application provide the following technical solutions:

[0007] A first aspect of embodiments of the present application provides an ultrasonic transducer, which includes:

[0008] a shell;

[0009] a matching layer arranged in the shell and connected to the shell;

[0010] a metal plating layer formed on the matching layer;

[0011] a piezoelectric ceramic arranged in the shell and located on a side of the metal plating layer away from the matching layer, wherein the piezoelectric ceramic includes a plurality of vibration units, and each of the plurality of vibration units is electrically connected to the metal plating layer.

[0012] In a possible implementation, the metal plating layer is connected to the piezoelectric ceramic through a first adhesive layer, and the thickness of the first adhesive layer is less than or equal to 20 μm.

[0013] In a possible implementation, the shell is made of insulating material; and / or, the thickness of the metal plating layer is 3-10 microns.

[0014] In a possible implementation, the shell further comprises a flange, the flange extends towards the center of the shell, and the flange encloses a first opening;

[0015] The matching layer is arranged on the flange and connected to the shell through a second adhesive layer.

[0016] In a possible implementation, the piezoelectric ceramic is provided with a plurality of grooves, the groove opening of each groove faces the metal plating layer, and the depth direction of the groove is parallel to the thickness direction of the piezoelectric ceramic; the plurality of grooves separate the piezoelectric ceramic into a plurality of vibration units.

[0017] The difference between the thickness of the piezoelectric ceramic and the depth of the groove is greater than or equal to 0.4 mm.

[0018] In a possible implementation, the outer surface of the shell is formed with an annular accommodating space, and the accommodating space is provided with a sealing structure.

[0019] The sealing structure is provided with an annular sealing groove, and the groove opening of the sealing groove faces the matching layer; wherein the sealing groove is adapted to accommodate a sealing protrusion of a metering pipeline.

[0020] In a possible implementation, the shell further comprises a second opening; along the thickness direction of the piezoelectric ceramic, the second opening and the first opening are oppositely arranged.

[0021] The ultrasonic transducer further comprises a plugging member arranged in the shell and plugging the second opening.

[0022] In a possible implementation, the shell comprises a stepped surface; the plugging member comprises a baffle and a potting layer arranged in layers, the baffle is arranged on the stepped surface and located in the shell;

[0023] Alternatively, the ultrasonic transducer further comprises a first lead wire and a second lead wire, one end of the first lead wire is electrically connected to the metal plating layer, and one end of the second lead wire is electrically connected to the piezoelectric ceramic; the other end of the first lead wire and the other end of the second lead wire pass through the plugging member and extend out of the shell.

[0024] The second aspect of the embodiment of the application provides an ultrasonic metering device, comprising a metering pipeline and two ultrasonic transducers as described in the first aspect; the two ultrasonic transducers are arranged on the metering pipeline in a spaced manner and communicate with each other.

[0025] A third aspect of this application provides an ultrasonic gas meter, including the ultrasonic metering device described in the second aspect.

[0026] The ultrasonic transducer, ultrasonic metering device, and ultrasonic gas meter provided in this application embodiment directly electroplate a metal coating onto the matching layer, and then place piezoelectric ceramics onto the metal coating. This allows several vibration units to be electrically connected to the metal coating. Compared to related technologies, this reduces the structural adhesive layer between the metal coating and the matching layer, thereby reducing the intensity attenuation of the ultrasonic signal, thus improving the sensitivity of the ultrasonic transducer and the metering accuracy of the ultrasonic gas meter.

[0027] In addition to the technical problems solved by the embodiments of this application, the technical features constituting the technical solutions, and the beneficial effects brought about by the technical features of these technical solutions described above, other technical problems that can be solved by the ultrasonic transducer, ultrasonic metering device, and ultrasonic gas meter provided by the embodiments of this application, other technical features included in the technical solutions, and the beneficial effects brought about by these technical features will be further explained in detail in the specific embodiments. Attached Figure Description

[0028] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0029] Figure 1 This is a schematic diagram of the structure of the ultrasonic transducer provided in the embodiments of this application;

[0030] Figure 2 A partial structural diagram of the ultrasonic transducer provided in the embodiments of this application. Figure 1 ;

[0031] Figure 3 A partial structural diagram of the ultrasonic transducer provided in the embodiments of this application. Figure 2 ;

[0032] Figure 4 For along Figure 3 A cross-sectional view along the AA direction;

[0033] Figure 5 A partial structural diagram of the ultrasonic transducer provided in the embodiments of this application. Figure 3 ;

[0034] Figure 6 For along Figure 5 Cross-sectional view along the BB direction;

[0035] Figure 7 A bottom view of the piezoelectric ceramic provided for the embodiment of the present application;

[0036] Figure 8 A side view of the piezoelectric ceramic provided for the embodiment of the present application.

[0037] Explanation of reference signs:

[0038] 100: housing; 110: flange portion; 120: first opening; 130: second opening; 140: step surface;

[0039] 200: matching layer;

[0040] 300: metal plating layer; 400: piezoelectric ceramic; 410: groove; 420: vibration unit;

[0041] 500: sealing member; 510: baffle; 520: potting adhesive layer;

[0042] 600: first lead wire;

[0043] 700: second lead wire;

[0044] 800: first adhesive layer;

[0045] 900: sealing structure; 910: sealing groove. DETAILED DESCRIPTION

[0046] As described in the background, the signal strength of the ultrasonic wave in the related art has a defect of attenuation in the transmission process. The inventor found the reason through research, which is that in order to electrically connect several vibration units together, it is usually necessary to set a metal layer between the piezoelectric ceramic and the matching layer, and adhesive layers are needed on both sides of the metal layer to realize the connection between the metal and the piezoelectric ceramic and the matching layer. In this way, the ultrasonic signal needs to pass through multiple layers in the transmission process, resulting in a certain attenuation of the strength of the ultrasonic signal, thereby reducing the sensitivity of the ultrasonic transducer and the measurement accuracy of the ultrasonic gas meter.

[0047] In view of the above technical problems, the embodiment of the present application provides an ultrasonic transducer, an ultrasonic metering device and an ultrasonic gas meter. A metal plating layer is directly electroplated on the matching layer, and the piezoelectric ceramic is arranged on the metal plating layer, so that the several vibration units can be electrically connected with the metal plating layer. Compared with the related art, the structural adhesive layer between the metal plating layer and the matching layer can be reduced, thereby reducing or even avoiding the attenuation of the strength of the ultrasonic signal, thereby improving the sensitivity of the ultrasonic transducer and the measurement accuracy of the ultrasonic gas meter.

[0048] To make the above-mentioned objectives, features, and advantages of the embodiments of this application more apparent and understandable, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0049] Please refer to Figure 1 and Figure 2 This application provides an ultrasonic transducer used in an ultrasonic metering device to measure the flow rate of fluid flowing through a metering pipeline. The fluid includes natural gas, liquid, or a gas-liquid mixture.

[0050] Please continue to refer to this. Figure 1 and Figure 2 The ultrasonic transducer includes a housing 100, which serves as the main component of the ultrasonic transducer and provides a mounting platform for other components. Furthermore, the housing 100 can also function as a connecting component for connecting the ultrasonic transducer to other structures. For example, the housing 100 can be connected to a metering pipeline.

[0051] The housing 100 is made of an insulating material. For example, it can be formed by injection molding of a plastic material. The plastic material may include polyetheretherketone (PEEK), polyimide (PI), or polycarbonate (PC).

[0052] The ultrasonic transducer also includes a matching layer 200, which is disposed within and connected to the housing 100. The matching layer 200 is a key component of the ultrasonic transducer, located between the piezoelectric ceramic 400 and the fluid medium, and is used to optimize the transmission efficiency of ultrasonic waves. In this embodiment, the housing 100 circumferentially encloses the matching layer 200, effectively protecting it and preventing impacts to the matching layer 200 from affecting the performance of the ultrasonic transducer.

[0053] It should be noted that the mating layer 200 can be connected to the housing 100 through the first adhesive layer, which can simplify the assembly of the mating layer 200 and the housing 100. In order to improve the connection stability between the mating layer 200 and the housing 100, the housing 100 includes a flange 110, which extends toward the center of the housing 100, so that the top of the flange 110 forms a bearing surface.

[0054] The mating layer 200 is disposed on the flange portion 110 and is connected to the housing 100 through the second adhesive layer. That is, the bottom surface of the mating layer 200 is laid on the bearing surface, and its side surface is connected to the housing 100 through the second adhesive layer.

[0055] It should be understood that the shape of the flange 110 can be selected in various ways. For example, the shape of the flange 110 is an annular shape. Another example is that the shape of the flange 110 is an arc segment. In order to improve the load-bearing capacity of the flange 110, there are multiple flanges 110, and the multiple flanges 110 are arranged at intervals along the circumference of the shell 100.

[0056] Furthermore, the flange 110 can be integral with the housing 100, or other options are possible. For example, along the height direction of the housing 100, i.e., attached... Figure 1 In the Z-direction, one end of the housing 100 is bent toward the center of the housing 100 to form a flange 110. This improves the connection strength between the flange 110 and the housing 100.

[0057] The flanged portion 110 encloses and forms the first opening 120, which facilitates the transmission of ultrasonic signals.

[0058] Please refer to Figure 4 and Figure 6 The ultrasonic transducer also includes a metal plating layer 300, which is formed on the matching layer 200. For example, a metal plating layer 300 of a certain thickness can be formed on the matching layer 200 by an electroplating process. In this embodiment, the metal plating layer 300 is made of silver or nickel.

[0059] In this embodiment, the thickness of the metal coating 300 is 3μm to 10μm. For example, the thickness of the metal coating 300 can be 3μm, 4μm, 5μm, 6μm, 7μm, 8μm, 9μm, 10μm, or any range between two values. By adjusting the thickness of the metal coating 300, this embodiment can ensure the conductivity of the metal coating 300 while avoiding excessive attenuation of the ultrasonic signal, thereby improving the sensitivity of the ultrasonic transducer.

[0060] Please continue to refer to this. Figure 1 The ultrasonic transducer also includes a piezoelectric ceramic 400, which is disposed within the housing 100 and located on the side opposite to the matching layer 200. For example, the piezoelectric ceramic 400 can be connected to the metal plating layer 300 via a first adhesive layer 800. Thus, the matching layer 200, the metal plating layer 300, and the piezoelectric ceramic 400 are disposed within the housing 100. The piezoelectric ceramic 400 includes several vibration units, all of which are electrically connected to the metal plating layer 300.

[0061] In this embodiment, a metal plating layer 300 is formed directly on the matching layer 200 by electroplating, and a piezoelectric ceramic 400 is disposed on the metal plating layer 300, so that several vibration units can be electrically connected to the metal plating layer 300. Compared with related technologies, the structural adhesive layer between the metal plating layer 300 and the matching layer 200 can be reduced, thereby reducing or even avoiding the intensity attenuation of the ultrasonic signal, thus improving the sensitivity of the ultrasonic transducer and the metering accuracy of the ultrasonic gas meter.

[0062] This embodiment directly connects the metal plating layer 300 and the matching layer 200, which not only simplifies the intermediate adhesive coating process and reduces costs, but also improves the intensity of the ultrasonic signal.

[0063] In this embodiment, the thickness of the first adhesive layer 800 is less than or equal to 20 μm. This avoids excessively thick layers in the stacked matching layer 200, metal plating layer 300, first adhesive layer, and piezoelectric ceramic 400, resulting in a more compact ultrasonic transducer structure. Furthermore, by appropriately controlling the thickness of the first adhesive layer, attenuation and reflection of the ultrasonic signal in the multilayer structure can be reduced, thereby improving the sensitivity of the ultrasonic transducer.

[0064] In one possible implementation, please refer to Figure 7 and Figure 8 The piezoelectric ceramic 400 has multiple grooves 410, which are spaced apart along a first direction, and each groove 410 extends along a second direction. The first and second directions are perpendicular to each other. Taking a square shape for the piezoelectric ceramic 400 as an example, the first direction can be either the length or width direction of the piezoelectric ceramic 400. For example, the first direction can be... Figure 7 In the X direction, the second direction can be Figure 7 Center Y direction.

[0065] The opening of each groove 410 faces the metal plating 300, and the depth direction of the groove 410 is parallel to the thickness direction of the piezoelectric ceramic 400. That is to say, the groove 410 is dug at the bottom of the piezoelectric ceramic 400.

[0066] Multiple grooves 410 divide the piezoelectric ceramic 400 into several vibration units. These vibration units can operate independently or collaboratively, enhancing the transmission and reception capabilities of ultrasonic waves. Furthermore, in this embodiment, the multiple grooves 410 extend only along the second direction, thus isolating the piezoelectric ceramic 400 from vibration in the first direction and reducing attenuation and reflection of the ultrasonic signal during transmission.

[0067] It should be noted that the number of grooves 410 in this embodiment can be varied; for example, there can be two, three, or even more grooves 410. For example, please refer to... Figure 7 andFigure 8 The number of grooves 410 is three.

[0068] It should also be understood that the distance between adjacent grooves 410 may be equal or unequal. For example, several vibration units 420 have equal widths in the first direction. The width of the vibration unit 420 is... Figure 7 In this way, the vibration units 420 with equal width have consistent amplitude and frequency characteristics when vibrating, which can produce a uniform sound field distribution, thereby improving the propagation efficiency of ultrasound in fluids.

[0069] In one possible implementation, the difference between the thickness of the piezoelectric ceramic 400 and the depth of the groove 410 is greater than or equal to 0.4 mm. Wherein, the thickness of the piezoelectric ceramic 400 is... Figure 8 The depth of groove 410 shown in the figure is H. Figure 8 h.

[0070] In this way, by reasonably adjusting the depth of the groove 410, a more stable vibration unit 420 can be formed, and the depth of the groove 410 can be avoided from being too large, thus ensuring the structural stability of the piezoelectric ceramic 400.

[0071] It should be noted that the width of the groove 410 in the first direction may be equal to or different from the depth of the groove 410. For example, the width of the groove 410 in the first direction is equal to the depth of the groove 410. For instance, both the width and depth of the groove 410 in the first direction are 0.4 mm.

[0072] In one possible implementation, the size of the first opening 120 in the first direction is larger than the maximum size of the piezoelectric ceramic 400. It should be noted that the maximum size of the piezoelectric ceramic 400 can be determined based on its shape. Specifically, the size of the first opening 120 can be... Figure 1 In the middle d, the maximum dimension of the piezoelectric ceramic 400 is a.

[0073] In some examples, when the piezoelectric ceramic 400 has a regular shape, such as a polygon, the maximum dimension of the piezoelectric ceramic 400 is the length of the diagonal of the polygon. For another example, please refer to... Figure 3 and Figure 5 When the piezoelectric ceramic 400 is circular, the maximum size of the piezoelectric ceramic 400 is the diameter of the circle.

[0074] In other examples, when the piezoelectric ceramic 400 is irregularly shaped, the maximum dimension refers to the maximum linear dimension of its circumscribed geometry (such as a rectangle or a circle).

[0075] In this embodiment, the size of the first opening 120 in the first direction is larger than the maximum size of the piezoelectric ceramic 400. This provides sufficient space for the piezoelectric ceramic 400 to move, reducing stress concentration caused by thermal expansion or mechanical vibration. It also reduces the reflection and scattering of ultrasonic signals during transmission, improving the sensitivity of the ultrasonic transducer.

[0076] In one possible implementation, continue to refer to Figure 1 The outer surface of the housing 100 forms an annular accommodating space. For example, the housing 100 may have different outer diameters; for instance, the housing 100 may include a first housing and a second housing connected to each other, both of which are cylindrical. In this case, the outer diameter of the first housing is larger than the outer diameter of the second housing, so that the housing forms an inverted convex shape, thereby forming an annular accommodating space on the outer surface of the housing 100.

[0077] A sealing structure 900 is provided within the accommodating space. The sealing structure 900 includes an annular sealing groove 910, the opening of which faces the matching layer 200. The sealing groove 910 is adapted to accommodate the sealing protrusion of the metering pipeline. This improves the sealing performance between the ultrasonic transducer and the metering pipeline.

[0078] It should be noted that the sealing groove 910 can be a regular U-shaped groove, or it can have other structures. For example, along the direction away from the center of the housing 100, the sealing structure 900 includes a first wall and a second wall disposed opposite to each other, wherein the first wall is connected to the housing 100. In the direction perpendicular to the mating layer 200, the length of the first wall is greater than that of the housing 100, which can increase the contact area between the first wall and the housing 100, thereby improving the connection strength between the sealing structure 900 and the housing 100.

[0079] In one possible implementation, the housing 100 further includes a second opening 130; the second opening 130 and the first opening 120 are disposed opposite each other along the thickness direction of the piezoelectric ceramic 400.

[0080] by Figure 1 and Figure 2 Taking the orientation shown as an example, the first opening 120 is the bottom opening of the housing 100, and the second opening 130 is the top opening of the housing 100. The above-mentioned components can be installed into the housing 100 through the second opening 130, which increases the ease of installation of the above-mentioned components.

[0081] The ultrasonic transducer also includes a sealing component 500, which is disposed within the housing 100 and seals the second opening 130. This creates a sealed space within the housing 100, preventing external dust, moisture, or other contaminants from entering the housing and improving the environmental adaptability and reliability of the ultrasonic transducer.

[0082] The sealing element 500 can be a single sealant or have other structures. Exemplarily, the sealing element 500 includes a baffle 510 and a potting compound layer 520 stacked together. The baffle 510 is disposed within the housing 100 and connected to the inner wall of the housing 100. The potting compound layer 520 fills the area enclosed by the baffle 510 and the housing 100. In this way, the baffle 510 provides a supporting base for the potting compound layer 520, facilitating the injection of the potting compound layer 520 and preventing corrosion and contamination of the piezoelectric ceramic 400 by moisture or pollutants, thereby improving the performance of the ultrasonic transducer.

[0083] In this embodiment, the piezoelectric ceramic 400 is disposed within the inner cavity of the housing 100, and the potting compound layer 520 is spaced apart from the piezoelectric ceramic 400, so that the potting compound layer 520 does not encapsulate the piezoelectric ceramic. During alternating hot and cold temperature shock tests, the shrinkage force generated by the thermal expansion and contraction of the potting compound layer 520 can be avoided from acting on the piezoelectric ceramic 400, improving the reliability and service life of the piezoelectric ceramic 400. Specifically, this design reduces stress concentration caused by temperature changes, preventing the piezoelectric ceramic 400 from cracking or degrading due to external stress, thereby ensuring its stability and durability in harsh environments. In this embodiment, the baffle 510 can be bonded to the inner wall of the housing 100, or it can be connected in other ways.

[0084] In order to improve the connection strength between the baffle 510 and the housing 100, in this embodiment, the housing 100 further includes a stepped surface 140, and the baffle 510 is disposed on the stepped surface 140 and located inside the housing 100.

[0085] The stepped surface 140 can be achieved by adjusting the inner diameter of the housing 100. For example, the housing 100 includes a first segment and a second segment, the diameter of the first segment being larger than the diameter of the second segment, thus forming a stepped surface 140 between the first segment and the second segment.

[0086] In this embodiment, the ultrasonic transducer further includes a first wire 600 and a second wire 700. One end of the first wire 600 is electrically connected to the metal plating layer 300, and one end of the second wire 700 is electrically connected to the piezoelectric ceramic 400.

[0087] The other end of the first wire 600 and the other end of the second wire 700 pass through the sealing member 500 and extend to the outside of the housing 100. One of the first wire 600 and the second wire 700 can be a positive electrode, and the other can be a negative electrode.

[0088] When the ultrasonic transducer is used as a transmitter, when an alternating current of a certain frequency is applied to the first conductor 600 and the second conductor 700, the piezoelectric ceramic 400 will vibrate in the thickness direction due to the inverse piezoelectric effect, thereby transmitting the ultrasonic waves through the matching layer 200.

[0089] Similarly, when the ultrasonic transducer acts as a receiver, when the sound wave is transmitted to the piezoelectric ceramic 400 through the matching layer 200, the piezoelectric ceramic 400 vibrates in the thickness direction. Due to the positive piezoelectric effect, an electrical signal is generated on the surface of the first conductor 600 and the second conductor 700.

[0090] In this embodiment, portions of the first conductor 600 and the second conductor 700 are wrapped with a potting compound layer 520, which can prevent moisture or other pollutants from corroding and contaminating the first conductor 600 and the second conductor 700.

[0091] This application also provides an ultrasonic metering device, including a metering pipe (not shown in the figure) and ultrasonic transducers as described in any of the above embodiments. Two ultrasonic transducers are spaced apart on the metering pipe and are interconnected with it. The two ultrasonic transducers are located on the same side of the metering pipe.

[0092] To facilitate the description of the functions of the two ultrasonic transducers, we may refer to them as the first ultrasonic transducer and the second ultrasonic transducer.

[0093] In practical application, ultrasonic waves are first transmitted from the first ultrasonic transducer to the second ultrasonic transducer, and the flight time T1 of the ultrasonic wave is measured. Then, the second ultrasonic transducer transmits ultrasonic waves back to the first ultrasonic transducer, and the flight time T2 of the ultrasonic wave is measured. Since the flow of the gas to be detected affects the two flight times, they differ. The gas velocity can be obtained using a pre-defined formula, thereby allowing the calculation of the gas flow rate. It should be noted that the formula used in this embodiment is existing technology, and will not be elaborated upon further in this embodiment.

[0094] Since the ultrasonic measuring device provided in this embodiment includes the ultrasonic transducer described in any of the above embodiments, it has all the structure and all the beneficial effects of the ultrasonic transducer, and will not be described in detail here.

[0095] This application also provides a gas meter including the ultrasonic metering device described in any of the above embodiments. It should be understood that the gas meter provided in this embodiment also includes a housing, in which the ultrasonic metering device is installed.

[0096] Since the gas meter provided in this embodiment includes the ultrasonic metering device described in any of the above embodiments, it has all the structure and all the beneficial effects of the ultrasonic metering device, and will not be described in detail here.

[0097] The various embodiments or implementation methods described in this specification are presented in a progressive manner. Each embodiment focuses on the differences from other embodiments, and the same or similar parts between the embodiments can be referred to each other.

[0098] It should be noted that the terms "one embodiment," "embodiment," "exemplary embodiment," "some embodiments," etc., mentioned in the specification indicate that the described embodiment may include a specific feature, structure, or characteristic, but not every embodiment necessarily includes that specific feature, structure, or characteristic. Furthermore, such phrases do not necessarily refer to the same embodiment. Moreover, when a specific feature, structure, or characteristic is described in connection with an embodiment, implementing such a feature, structure, or characteristic in conjunction with other embodiments, whether explicitly described or not, is within the knowledge scope of those skilled in the art.

[0099] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. An ultrasonic transducer, characterized in that, include: case; A matching layer is disposed within the housing and connected to the housing; A metal coating formed on the mating layer; A piezoelectric ceramic is disposed within the housing and located on the side of the metal plating away from the matching layer. The piezoelectric ceramic includes several vibration units, all of which are electrically connected to the metal plating.

2. The ultrasonic transducer according to claim 1, characterized in that, The metal coating is connected to the piezoelectric ceramic via a first adhesive layer, the thickness of which is less than or equal to 20 μm.

3. The ultrasonic transducer according to claim 1, characterized in that, The housing is made of an insulating material; and / or the thickness of the metal plating is 3 μm to 10 μm.

4. The ultrasonic transducer according to claim 1, characterized in that, The housing also includes a flange that extends toward the center of the housing and forms a first opening; The matching layer is disposed on the inner side of the flange and is connected to the housing through the second adhesive layer.

5. The ultrasonic transducer according to any one of claims 1-4, characterized in that, The piezoelectric ceramic has multiple grooves, with the opening of each groove facing the metal coating, and the depth direction of the groove is parallel to the thickness direction of the piezoelectric ceramic; the multiple grooves divide the piezoelectric ceramic into several vibration units; The difference between the thickness of the piezoelectric ceramic and the depth of the groove is greater than or equal to 0.4 mm.

6. The ultrasonic transducer according to any one of claims 1-4, characterized in that, The outer surface of the housing has an annular accommodating space, and the accommodating space is provided with a sealing structure; The sealing structure is provided with an annular sealing groove, and the opening of the sealing groove faces the matching layer; wherein, the sealing groove is adapted to accommodate the sealing protrusion of the metering pipe.

7. The ultrasonic transducer according to any one of claims 1-4, characterized in that, The housing further includes a second opening; the second opening and the first opening are arranged opposite to each other along the thickness direction of the piezoelectric ceramic; The ultrasonic transducer also includes a sealing element disposed within the housing and sealing the second opening.

8. The ultrasonic transducer according to claim 7, characterized in that, The housing includes a stepped surface; the sealing element includes a stacked baffle and a potting compound layer, the baffle being disposed on the stepped surface and located inside the housing; Alternatively, the ultrasonic transducer may further include a first wire and a second wire, one end of the first wire being electrically connected to the metal plating layer, and one end of the second wire being electrically connected to the piezoelectric ceramic; the other ends of the first wire and the other ends of the second wire pass through the sealing member and extend to the outside of the housing.

9. An ultrasonic measuring device, characterized in that, It includes a metering pipe and two ultrasonic transducers as described in any one of claims 1-8; the two ultrasonic transducers are spaced apart on the metering pipe and are interconnected with the metering pipe.

10. An ultrasonic gas meter, characterized in that, Includes the ultrasonic measuring device as described in claim 9.

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