Ultrasonic transducer

Abstract

The utility model belongs to the technical field of transducers, and discloses an ultrasonic transducer. The ultrasonic transducer comprises a shell, piezoelectric ceramics, a cover plate, a matching layer piece and a leading-out wire set, a containing cavity is formed in the shell, an opening is formed in the shell, the piezoelectric ceramics are arranged in the containing cavity, the cover plate covers the opening and can shield electromagnetic interference, the matching layer piece is attached to the piezoelectric ceramics and arranged on the side away from the cover plate, and the leading-out wire set is arranged on the matching layer piece. And the outgoing line group is connected with the positive electrode of the piezoelectric ceramic and the negative electrode of the piezoelectric ceramic. Through the arrangement that the cover plate can shield electromagnetic interference, the ultrasonic transducer can shield external electromagnetic field interference, and the production cost of the ultrasonic transducer can be reduced.

Description

Technical Field

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

[0002] Ultrasonic transducer is one of the core components of ultrasonic products. It uses the direct piezoelectric effect or inverse piezoelectric effect of piezoelectric ceramic materials to convert mechanical vibration ultrasonic signals into electrical signals, or convert electrical signals into mechanical vibration ultrasonic signals.

[0003] Ultrasonic gas meters use this positive and negative piezoelectric effect to transmit and receive electrical and ultrasonic signals. In a gas medium, ultrasonic signals will be significantly attenuated during propagation, and their attenuation coefficient is proportional to the square of the transducer frequency. Therefore, in order to prevent the ultrasonic signal from attenuating too quickly, the transducer frequency currently used in ultrasonic gas meters is low. This makes ultrasonic gas meters susceptible to interference from external electromagnetic fields.

[0004] In order to solve the problem that the ultrasonic transducer is easily interfered by the external electromagnetic field in the prior art, the transducer housing is set as a housing with electromagnetic shielding function, and the lead wire group is provided with a shielding wire that can shield the external electromagnetic interference, so as to prevent the ultrasonic transducer from being interfered by the external electromagnetic field. Although the ultrasonic transducer in the prior art can shield the external electromagnetic field interference, the production cost is relatively high, which makes it difficult to mass produce in the actual production process.

[0005] Therefore, it is urgent to propose an ultrasonic transducer to solve the above problems. Utility Model Content

[0006] The purpose of the utility model is to provide an ultrasonic transducer, which can not only shield the interference of external electromagnetic fields, but also reduce the production cost of the ultrasonic transducer.

[0007] To achieve this purpose, the utility model adopts the following technical solutions:

[0008] Ultrasonic transducer, including:

[0009] A housing, wherein a receiving cavity is provided in the housing, and an opening is provided on the housing;

[0010] A piezoelectric ceramic is disposed in the accommodating cavity;

[0011] A cover plate, which is disposed on the opening and can shield electromagnetic interference;

[0012] A matching layer, the matching layer is bonded to the piezoelectric ceramic and is arranged on a side away from the cover plate;

[0013] A lead wire group is connected to the positive electrode of the piezoelectric ceramic and the negative electrode of the piezoelectric ceramic.

[0014] Preferably, a pad is provided on the cover plate, a first welding point and a second welding point are provided on the pad, and the lead wire group includes:

[0015] A positive electrode lead wire, one end of which is connected to the positive electrode of the piezoelectric ceramic, and the other end of which is connected to the first welding point;

[0016] A negative electrode lead wire, one end of which is connected to the negative electrode of the piezoelectric ceramic, and the other end of which is connected to the second welding point.

[0017] Preferably, a third welding point is further provided on the welding pad, and the ultrasonic transducer further includes a shielding wire group, and the shielding wire group includes:

[0018] A shielding wire positive electrode wire connected to the second welding point;

[0019] A shielding line negative electrode conductor, wherein the shielding line negative electrode conductor is connected to the first welding point;

[0020] A shielding layer metal wire is connected to the third welding point.

[0021] Preferably, the positive wire of the shielding wire is connected to the side of the second welding point away from the piezoelectric ceramic, the negative wire of the shielding wire is connected to the side of the first welding point away from the piezoelectric ceramic, and the shielding layer metal wire is connected to the side of the third welding point away from the piezoelectric ceramic.

[0022] Preferably, the soldering pad is provided with a through hole, the positive conductor of the shielding wire is connected to the side of the second soldering point close to the piezoelectric ceramic, the negative conductor of the shielding wire is connected to the side of the first soldering point close to the piezoelectric ceramic, the positive conductor of the shielding wire and the negative conductor of the shielding wire both pass through the through hole, and the shielding layer metal wire is connected to the side of the third soldering point close to the piezoelectric ceramic.

[0023] Preferably, the ultrasonic transducer further comprises a shielding wire group, and the shielding wire group comprises:

[0024] A shielding wire positive electrode wire connected to the second welding point;

[0025] A shielding line negative electrode conductor, wherein the shielding line negative electrode conductor is connected to the first welding point;

[0026] The metal wire of the shielding layer is the same wire as the negative wire of the shielding wire.

[0027] Preferably, the positive wire of the shielding wire is connected to a side of the second welding point away from the piezoelectric ceramic, and the negative wire of the shielding wire is connected to a side of the first welding point away from the piezoelectric ceramic.

[0028] Preferably, the soldering pad is provided with a through hole, the positive conductor of the shielding wire is connected to the side of the second soldering point close to the piezoelectric ceramic, the negative conductor of the shielding wire is connected to the side of the first soldering point close to the piezoelectric ceramic, and the positive conductor of the shielding wire and the metal wire of the shielding layer both pass through the through hole.

[0029] Preferably, the ultrasonic transducer further comprises a sealing layer, and the sealing layer is arranged on a side of the cover plate away from the piezoelectric ceramic.

[0030] Preferably, the cover plate is a PCB board, and a conductive material is coated on the surface of the PCB board; and / or

[0031] The cover plate is made of metal material.

[0032] Beneficial effects:

[0033] This embodiment improves the design of the ultrasonic transducer, and the ultrasonic transducer includes a shell, a piezoelectric ceramic, a cover plate, a matching layer, and a lead wire group. A accommodating cavity is provided in the shell, an opening is provided on the shell, the piezoelectric ceramic is arranged in the accommodating cavity, the cover plate is covered on the opening, the cover plate can shield electromagnetic interference, the matching layer is fitted with the piezoelectric ceramic, and is arranged on a side away from the cover plate, and the lead wire group is connected to the positive electrode of the piezoelectric ceramic and the negative electrode of the piezoelectric ceramic.

[0034] The cover plate is capable of shielding electromagnetic interference, thereby effectively avoiding the adverse effect of external electromagnetic interference on the signal transmission of the lead wire group, and effectively preventing external electromagnetic interference from entering the accommodating cavity through the assembly gap between the shell and the lead wire group. By separately setting the cover plate to be able to shield electromagnetic interference, the reliability and stability of the electromagnetic shielding function of the ultrasonic transducer can be guaranteed, and the production cost of setting both the shell and the cover plate to be able to shield electromagnetic interference in the prior art can be further reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments of the present invention. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the contents of the embodiments of the present invention and these drawings without paying any creative work.

[0036] Figure 1It is a schematic diagram of the structure of the ultrasonic transducer provided in the first embodiment of the utility model;

[0037] Figure 2 This is a schematic structural diagram of a welding method of a lead wire group and a shielding wire group provided in the first embodiment of the utility model;

[0038] Figure 3 This is a structural schematic diagram of a welding method of a lead wire group and a shielding wire group from another perspective provided by the first embodiment of the utility model;

[0039] Figure 4 This is a schematic structural diagram of the welding method of the lead wire group and the shielding wire group provided in the second embodiment of the utility model;

[0040] Figure 5 This is a structural schematic diagram of a welding method of a lead wire group and a shielding wire group from another perspective provided by the second embodiment of the present utility model;

[0041] Figure 6 This is a schematic structural diagram of the welding method of the lead wire group and the shielding wire group provided in the third embodiment of the present utility model;

[0042] Figure 7 This is a schematic structural diagram of a welding method of a lead wire group and a shielding wire group from another perspective provided in the third embodiment of the present utility model;

[0043] Figure 8 This is a schematic structural diagram of the welding method of the lead wire group and the shielding wire group provided in the fourth embodiment of the utility model;

[0044] Fig. 9 It is a structural schematic diagram of the welding method of the lead wire group and the shielding wire group from another perspective provided by the fourth embodiment of the present utility model.

[0045] In the figure:

[0046] 1. Shell; 11. Accommodating cavity;

[0047] 2. Cover plate;

[0048] 3. Lead wire group; 31. Positive lead wire; 32. Negative lead wire;

[0049] 4. Shielding wire group; 41. Shielding wire positive conductor; 42. Shielding wire negative conductor; 43. Shielding layer metal wire;

[0050] 5. Sealing layer. DETAILED DESCRIPTION

[0051] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only the parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0052] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0053] In the present utility model, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0054] In the description of this embodiment, the terms "upper", "lower", "left", "right" and other directions or positional relationships are based on the directions or positional relationships shown in the drawings, and are only for the convenience of description and simplified operation, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation of the present invention. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.

[0055] Embodiment 1

[0056] Figure 1 FIG. 1 shows a schematic diagram of the structure of the ultrasonic transducer provided in the first embodiment of the present invention. Figure 2 The figure shows a schematic structural diagram of the welding method of the lead wire group 3 and the shielding wire group 4 provided in the first embodiment. Figure 3 FIG. 2 shows a schematic diagram of the welding method of the lead wire group 3 and the shielding wire group 4 from another perspective provided in the first embodiment. Figure 1-Figure 3As shown, this embodiment discloses an ultrasonic transducer, which includes a shell 1, a piezoelectric ceramic, a cover plate 2, a matching layer, and a lead wire group 3. A accommodating cavity 11 is provided in the shell 1, an opening is provided on the shell 1, the piezoelectric ceramic is arranged in the accommodating cavity 11, the cover plate 2 is covered on the opening, the cover plate 2 can shield electromagnetic interference, the matching layer is fitted with the piezoelectric ceramic, and is arranged on a side away from the cover plate 2, and the lead wire group 3 is connected to the positive electrode of the piezoelectric ceramic and the negative electrode of the piezoelectric ceramic.

[0057] The cover plate 2 is configured to shield electromagnetic interference, thereby effectively avoiding the adverse effect of external electromagnetic interference on the signal transmission of the lead wire group 3, and effectively avoiding the external electromagnetic interference from entering the accommodating cavity 11 through the assembly gap between the shell 1 and the lead wire group 3. By separately configuring the cover plate 2 to be able to shield electromagnetic interference, the reliability and stability of the electromagnetic shielding function of the ultrasonic transducer can be guaranteed, and the production cost of configuring both the shell 1 and the cover plate 2 to be able to shield electromagnetic interference in the prior art can be further reduced.

[0058] In this embodiment, the cover plate 2 is made of a PCB board and coated with a conductive material on its surface, so that the cover plate 2 has the function of shielding electromagnetic interference, especially has a strong shielding function for low-frequency electromagnetic waves. In other embodiments, the cover plate 2 can also be made of a metal material. This embodiment does not specifically limit the specific material of the cover plate 2. Any material that can shield electromagnetic interference should be within the protection scope of this embodiment.

[0059] Furthermore, a welding pad is provided on the cover plate 2, and a first welding point and a second welding point are provided on the welding pad. The lead wire group 3 includes a positive lead wire 31 and a negative lead wire 32. One end of the positive lead wire 31 is connected to the positive electrode of the piezoelectric ceramic, and the other end is connected to the first welding point. One end of the negative lead wire 32 is connected to the negative electrode of the piezoelectric ceramic, and the other end is connected to the second welding point. The positive lead wire 31 is provided to connect the positive electrode of the piezoelectric ceramic to the first welding point, and the negative lead wire 32 is provided to connect the negative electrode of the piezoelectric ceramic to the second welding point.

[0060] It should be noted that when the ultrasonic transducer is used as a transmitting end, an electrical signal of a specific pulse frequency is input through the positive lead wire 31 and the negative lead wire 32, and the piezoelectric ceramic will undergo periodic deformation, thereby driving the matching layer to produce periodic deformation and emit a regular ultrasonic signal, thereby realizing the conversion of the electrical signal into a mechanical vibration ultrasonic signal; when the ultrasonic transducer is used as a receiving end, since the material of the matching layer is a special organic matter, it can absorb the ultrasonic signal emitted by the transmitting end, the piezoelectric ceramic will deform periodically and convert it into an electrical signal to be transmitted to the circuit, thereby realizing the conversion of the mechanical vibration ultrasonic signal into an electrical signal, so that the ultrasonic transducer can be used as both a receiving end and a transmitting end.

[0061] Furthermore, the ultrasonic transducer also includes a sealing layer 5, which is arranged on the side of the cover plate 2 away from the piezoelectric ceramic. The setting of the sealing layer 5 can prevent external electromagnetic interference from entering the accommodating cavity 11 from the cover plate 2 or the connecting gap between the cover plate 2 and the shell 1, thereby ensuring the sealing of the cover plate 2 and further improving the reliability and stability of the ultrasonic transducer.

[0062] Preferably, the sealing layer 5 can be made of resin material, which can be selected according to actual needs. This embodiment does not limit the specific material of the sealing layer 5.

[0063] Furthermore, a third welding point is provided on the welding pad, and the ultrasonic transducer also includes a shielding wire group 4, which includes a shielding wire positive wire 41, a shielding wire negative wire 42 and a shielding layer metal wire 43. The shielding wire positive wire 41 is connected to the second welding point, the shielding wire negative wire 42 is connected to the first welding point, and the shielding layer metal wire 43 is connected to the third welding point, so that the shielding wire positive wire 41 is conductive with the negative lead wire 32, and the shielding wire negative wire 42 is conductive with the positive lead wire 31.

[0064] Furthermore, the pad is provided with a through hole, the shielding wire positive wire 41 is connected to the side of the second welding point close to the piezoelectric ceramic, the shielding wire negative wire 42 is connected to the side of the first welding point close to the piezoelectric ceramic, the shielding wire positive wire 41 and the shielding wire negative wire 42 both pass through the through hole, and the shielding layer metal wire 43 is connected to the side of the third welding point close to the piezoelectric ceramic, so that the shielding wire group 4 can shield electromagnetic interference, thereby preventing the positive lead wire 31, the negative lead wire 32 and the piezoelectric ceramic from being affected by electromagnetic interference.

[0065] Embodiment 2

[0066] The ultrasonic transducer provided in this embodiment is substantially the same as that in the first embodiment. The difference between the ultrasonic transducer provided in this embodiment and that in the first embodiment is as follows:

[0067] Figure 4 The figure shows a schematic structural diagram of the welding method of the lead wire group 3 and the shielding wire group 4 provided in the second embodiment. Figure 5 FIG. 2 shows a schematic diagram of the welding method of the lead wire group 3 and the shielding wire group 4 from another perspective provided in the second embodiment. Figure 4 and Figure 5 Combined with Figure 1As shown, the positive conductor 41 of the shielding wire is connected to the side of the second welding point away from the piezoelectric ceramic, the negative conductor 42 of the shielding wire is connected to the side of the first welding point away from the piezoelectric ceramic, and the shielding layer metal wire 43 is connected to the side of the third welding point away from the piezoelectric ceramic, so that the ultrasonic transducer can change the connection method according to different actual needs to adapt to different production needs and improve the versatility of the ultrasonic transducer.

[0068] Embodiment 3

[0069] The ultrasonic transducer provided in this embodiment is substantially the same as that in the first embodiment. The difference between the ultrasonic transducer provided in this embodiment and that in the first embodiment is as follows:

[0070] Figure 6 The figure shows a schematic structural diagram of the welding method of the lead wire group 3 and the shielding wire group 4 provided in the third embodiment. Figure 7 FIG. 2 shows a schematic diagram of the welding method of the lead wire group 3 and the shielding wire group 4 from another perspective provided in the third embodiment. Figure 6 and Figure 7 Combined with Figure 1 As shown, the ultrasonic transducer also includes a shielding wire group 4, which includes a shielding wire positive wire 41, a shielding wire negative wire 42, and a shielding layer metal wire 43. The shielding wire positive wire 41 is connected to the second welding point, the shielding wire negative wire 42 is connected to the first welding point, and the shielding layer metal wire 43 is the same wire as the shielding wire negative wire 42. By setting the shielding layer metal wire 43 and the shielding wire negative wire 42 as the same wire, the number of welding points on the pad is reduced, and the sealing of the accommodating cavity 11 is improved.

[0071] Furthermore, the welding pad is provided with a through hole, the shielding wire positive conductor 41 is connected to the side of the second welding point close to the piezoelectric ceramic, the shielding wire negative conductor 42 is connected to the side of the first welding point close to the piezoelectric ceramic, and the shielding wire positive conductor 41 and the shielding layer metal wire 43 both pass through the through hole, so that the shielding wire group 4 can shield electromagnetic interference, thereby preventing the positive lead wire 31, the negative lead wire 32 and the piezoelectric ceramic from being affected by electromagnetic interference.

[0072] Embodiment 4

[0073] The ultrasonic transducer provided in this embodiment is substantially the same as that in the third embodiment. The difference between the ultrasonic transducer provided in this embodiment and that in the third embodiment is as follows:

[0074] Figure 8 The figure shows a schematic structural diagram of the welding method of the lead wire group 3 and the shielding wire group 4 provided in the fourth embodiment. Fig. 9 FIG. 4 shows a schematic diagram of the welding method of the lead wire group 3 and the shielding wire group 4 from another perspective provided in the fourth embodiment. Figure 8and Fig. 9 Combined with Figure 1 As shown, the shielding wire positive conductor 41 is connected to the side of the second welding point away from the piezoelectric ceramic, and the shielding layer metal wire 43 is connected to the side of the first welding point away from the piezoelectric ceramic, so that the ultrasonic transducer can change the connection method according to different actual needs to adapt to different production needs and improve the versatility of the ultrasonic transducer.

[0075] Obviously, the above embodiments of the present invention are merely examples for the purpose of clearly illustrating the present invention, and are not intended to limit the implementation methods of the present invention. For those skilled in the art, various obvious changes, readjustments and substitutions can be made without departing from the scope of protection of the present invention. It is not necessary and impossible to list all implementation methods here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention shall be included in the scope of protection of the claims of the present invention.

Claims

1. An ultrasonic transducer, characterized in that: include: A housing (1), wherein a receiving cavity (11) is provided in the housing (1), and an opening is provided on the housing (1); A piezoelectric ceramic is arranged in the accommodating cavity (11); A cover plate (2) is arranged on the opening, and the cover plate (2) is capable of shielding electromagnetic interference; A matching layer, the matching layer being in contact with the piezoelectric ceramic and being arranged on a side away from the cover plate (2); A lead wire group (3), wherein the lead wire group (3) is connected to the positive electrode of the piezoelectric ceramic and the negative electrode of the piezoelectric ceramic.

2. The ultrasonic transducer according to claim 1, characterized in that: The cover plate (2) is provided with a soldering pad, the soldering pad is provided with a first soldering point and a second soldering point, and the lead wire group (3) comprises: A positive electrode lead wire (31), one end of the positive electrode lead wire (31) being connected to the positive electrode of the piezoelectric ceramic, and the other end of the positive electrode lead wire (31) being connected to the first welding point; A negative electrode lead wire (32), one end of the negative electrode lead wire (32) is connected to the negative electrode of the piezoelectric ceramic, and the other end is connected to the second welding point.

3. The ultrasonic transducer according to claim 2, characterized in that: The pad is also provided with a third welding point. The ultrasonic transducer further comprises a shielding wire group (4), and the shielding wire group (4) comprises: A shielded wire positive electrode conductor (41), the shielded wire positive electrode conductor (41) being connected to the second welding point; A shielding wire negative electrode conductor (42), wherein the shielding wire negative electrode conductor (42) is connected to the first welding point; A shielding layer metal wire (43), wherein the shielding layer metal wire (43) is connected to the third welding point.

4. The ultrasonic transducer according to claim 3, characterized in that: The shielding wire positive wire (41) is connected to the side of the second welding point away from the piezoelectric ceramic, the shielding wire negative wire (42) is connected to the side of the first welding point away from the piezoelectric ceramic, and the shielding layer metal wire (43) is connected to the side of the third welding point away from the piezoelectric ceramic.

5. The ultrasonic transducer according to claim 3, characterized in that: The solder pad is provided with a through hole, the shielding wire positive wire (41) is connected to the side of the second soldering point close to the piezoelectric ceramic, the shielding wire negative wire (42) is connected to the side of the first soldering point close to the piezoelectric ceramic, the shielding wire positive wire (41) and the shielding wire negative wire (42) both pass through the through hole, and the shielding layer metal wire (43) is connected to the side of the third soldering point close to the piezoelectric ceramic.

6. The ultrasonic transducer according to claim 2, characterized in that: The ultrasonic transducer further comprises a shielding wire group (4), wherein the shielding wire group (4) comprises: A shielded wire positive electrode conductor (41), the shielded wire positive electrode conductor (41) being connected to the second welding point; A shielding wire negative electrode conductor (42), wherein the shielding wire negative electrode conductor (42) is connected to the first welding point; The shielding layer metal wire (43) is the same wire as the shielding wire negative electrode wire (42).

7. The ultrasonic transducer according to claim 6, characterized in that: The shielding wire positive electrode wire (41) is connected to the side of the second welding point away from the piezoelectric ceramic, and the shielding wire negative electrode wire (42) is connected to the side of the first welding point away from the piezoelectric ceramic.

8. The ultrasonic transducer according to claim 6, characterized in that: The pad is provided with a through hole, the shielding wire positive wire (41) is connected to the side of the second welding point close to the piezoelectric ceramic, the shielding wire negative wire (42) is connected to the side of the first welding point close to the piezoelectric ceramic, and the shielding wire positive wire (41) and the shielding layer metal wire (43) both pass through the through hole.

9. The ultrasonic transducer according to any one of claims 1 to 8, characterized in that: The ultrasonic transducer further comprises a sealing layer (5), wherein the sealing layer (5) is arranged on a side of the cover plate (2) away from the piezoelectric ceramic.

10. The ultrasonic transducer according to any one of claims 1 to 8, characterized in that: The cover plate (2) is a PCB board, and a conductive material is coated on the surface of the PCB board; and / or The cover plate (2) is made of metal material.

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