Transducer design method and transducer

Abstract

The invention discloses a method for designing a transducer. The method comprises the following steps of: setting required frequency and power; the length of the front end cover is increased, and the length of the front end cover is increased on the basis of the length of the half-wavelength front end cover; adjusting the length and / or radian of the front end cover to enable the output frequency of the front end cover to accord with the required frequency; wherein the length and the radian are inversely proportional to the frequency. The length of the front end cover is increased, and the length and / or radian (diameter) of the front end cover is adjusted, so that the redesigned transducer outputs required frequency and power, the redesigned transducer and a conventional transducer with a half-wavelength design realize the same frequency output under the condition of selecting the same material, the redesigned transducer has a longer front end cover space, and the energy efficiency is improved. According to the energy converter, the piezoelectric ceramic pieces can be conveniently added in the subsequent process, connection with other elements is facilitated, the energy converter is converted from the half-wavelength design to the double-wavelength design, the problem that the length of an existing energy converter with the half-wavelength design is insufficient after the frequency is increased is solved, and high-frequency and high-power output of the energy converter is achieved.

Description

Technical Field

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

[0002] An ultrasonic transducer is a device that converts electromagnetic energy into mechanical energy (acoustic energy), usually made of piezoelectric ceramics or other magnetostrictive materials. Common examples of ultrasonic transducers include ultrasonic cleaners, ultrasonic atomizers, B-ultrasound probes, etc.

[0003] Currently, common power ultrasound is more applied to scenarios with lower frequencies and lower powers below 45KHZ, that is, the transducer is designed as a half-wavelength. However, as the application scenarios of ultrasound continue to extend and expand, the requirements for transducers are getting higher and higher. The public has begun to pursue power ultrasound with higher frequencies and higher powers in order to bring better usage effects.

[0004] Existing transducers have the following problems in obtaining higher-frequency power ultrasound: The cross-sectional area of a transducer designed with a half-wavelength will decrease, making it impossible to output a higher power; in addition, its length will also decrease correspondingly with the longitudinal wavelength and the transverse wavelength, resulting in impossible assembly. Summary of the Invention

[0005] In view of the deficiencies of the prior art, the present invention provides a transducer design method and a transducer.

[0006] A transducer design method disclosed by the present invention includes:

[0007] Setting the required frequency and power;

[0008] Increasing the length of the front end cap, and increasing the length of the front end cap based on the length of the front end cap of a half-wavelength.

[0009] Adjusting the length and / or radian of the front end cap so that its output frequency matches the required frequency; wherein, both the length and the radian are inversely proportional to the frequency.

[0010] According to an embodiment of the present invention, after increasing the length of the front end cap, increasing the number of piezoelectric ceramic chips to achieve the required power;

[0011] It further includes checking the output power of the transducer model, and its checking formula is:

[0012] P = a * n * V

[0013] a: The power coefficient of the working mode of the piezoelectric ceramic chip, wherein, a = 0.1 - 9.9;

[0014] n: The number of piezoelectric ceramic chips;

[0015] V: The volume of the piezoelectric ceramic chip.

[0016] According to an embodiment of the present invention, a plurality of piezoelectric ceramic sheets are grouped, and there are intervals between groups.

[0017] According to an embodiment of the present invention, the maximum amplitude output point of the transducer model is obtained through finite element analysis, and a plurality of notches are opened at intervals in the forward and / or reverse directions of the maximum amplitude output point.

[0018] According to an embodiment of the present invention, the notches are opened in at least one of an inclined slot and a straight slot.

[0019] According to an embodiment of the present invention, the maximum amplitude output point of the transducer model is obtained through finite element analysis, and a through hole is opened at the maximum amplitude output point.

[0020] According to an embodiment of the present invention, it further includes: symmetrically arranging a front end cover and a rear end cover to form a two-way output.

[0021] A transducer disclosed by the present invention includes: a first end cover, a second end cover, a plurality of ceramic parts, a plurality of pole pieces, and a connecting piece. The first end cover and the second end cover are connected by the connecting piece, and the plurality of ceramic parts and the plurality of pole pieces are arranged alternately between the first end cover and the second end cover.

[0022] According to an embodiment of the present invention, the first end cover has multiple variable ratio regions, and the multiple variable ratio regions extend in a direction away from the ceramic parts and are connected in sequence.

[0023] According to an embodiment of the present invention, a plurality of composite slots are spaced apart on the surface of the first end cover.

[0024] The beneficial effects of the present invention are as follows: the length of the front end cover is increased. At the same time, by adjusting the length and / or radian (diameter) of the front end cover, the redesigned transducer outputs the required frequency and power. The redesigned transducer and the transducer designed by the conventional half-wavelength design achieve the same frequency output when using the same materials. Among them, the redesigned transducer has a longer front end cover space, which is not only convenient for the subsequent addition of piezoelectric ceramic sheets but also conducive to the connection with other components. The transducer is changed from a half-wavelength design to a double-wavelength design, overcoming the problem of insufficient length of the existing half-wavelength design transducer after the frequency is increased, and thus realizing the high-frequency and high-power output of the transducer. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The schematic embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation to the present application. In the drawings:

[0026] Figure 1 It is a structural block diagram in the embodiment;

[0027] Figure 2 Structural diagram in the embodiment;

[0028] Figure 3 Structural diagram in the embodiment;

[0029] Figure 4 In the embodiment.

[0030] Description of the reference numerals in the drawings

[0031] 1 - First end cap; 11 - Turns ratio area; 111 - Small - diameter section; 112 - Large - diameter section; 12 - Composite groove; 13 - Cooling hole;

[0032] 2 - Second end cap;

[0033] 3 - Ceramic part;

[0034] 4 - Electrode tab;

[0035] 5 - Connecting piece. Specific implementation manners

[0036] The following will disclose multiple implementation manners of the present invention with diagrams. For the sake of clear illustration, many practical details will be described together in the following narrative. However, it should be understood that these practical details are not used to limit the present invention. That is to say, in some implementation manners of the present invention, these practical details are not necessary. In addition, for the purpose of simplifying the diagrams, some conventional structures and components will be shown in a simple schematic manner in the diagrams.

[0037] In addition, in the present invention, descriptions such as "first", "second", etc. are only for descriptive purposes, and do not particularly refer to the order or sequence, nor are they used to limit the present invention. They are merely used to distinguish components or operations described with the same technical terms, and cannot be understood as indicating or implying their relative importance or implicitly indicating the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include at least one of such features. In addition, the technical solutions between various embodiments can be combined with each other, but it must be based on the fact that those skilled in the art can implement them. When the combination of technical solutions results in contradictions or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0038] Embodiment 1

[0039] The transducer design method of the present application includes:

[0040] Set the actual required frequency and power; the required frequency and power are set by the user according to the expected achievable values, including frequencies that cannot be achieved by existing half-wavelength designed transducers. For example, the limit of existing transducers is 60KHZ, and beyond this limit, it is impossible to assemble a transducer due to the limited assembly space; now the required frequency can be preset to 70KHZ, 80KH, 100KHZ, etc.

[0041] Increase the length of the front end cap; extend the length of the front end cap so that it will not cause the compression phenomenon of the front end cap length due to the compression of the longitudinal wavelength and the transverse wavelength caused by the frequency increase.

[0042] Establish a transducer model and perform finite element analysis; after extending the front end cap, assemble the corresponding piezoelectric ceramic sheets, electrodes, and the rear end cap to form a transducer model, and use existing finite element analysis software to simulate and analyze the working state of the transducer model.

[0043] Adjust the length and / or radian of the front end cap: Based on the finite element analysis, according to the output frequency of the transducer model obtained from the finite element analysis, by adjusting at least one of the length and / or radian of the front end cap, the output frequency of the transducer model changes so that the output frequency of the transducer model matches the required frequency; among them, both the length and the radian of the front end cap are inversely proportional to the frequency, that is, shortening the length or reducing the radian can achieve frequency increase. In this embodiment, the radian is related to the diameter of the front end cap, and by adjusting the diameter of the front end cap, the adjustment of its radian is achieved.

[0044] Furthermore, when increasing the length of the front end cap, it can be multiplied based on the length of the front end cap corresponding to the same frequency in the half-wavelength design. At this time, the frequency will be different from that of the half-wavelength designed transducer, and then the length and / or radian of the front end cap are adjusted through finite element analysis.

[0045] Even further, in order to achieve the required power, after increasing the length of the front end cap, there is more design space, and then the number of piezoelectric ceramic sheets can be increased to achieve an increase in output power, improving the problem of insufficient output power after the frequency increase of the traditional half-wavelength designed transducer. That is to say, even at the same output frequency, the power output by the transducer in this embodiment will be multiple times that of the traditional one, that is, the traditional half-wavelength design is transformed into a double-wavelength design. In specific applications, after adding multiple piezoelectric ceramic sheets, the multiple piezoelectric ceramic sheets can be stacked in sequence at one place, or the multiple piezoelectric ceramic sheets can be grouped, and then the different groups are spaced apart. Using the grouped form is beneficial to avoid the stress points of the transducer, thereby avoiding the phenomenon of the piezoelectric ceramic sheets cracking.

[0046] Furthermore, after the front end cover is enlarged, multi-stage ratio change processing can be performed in the area of the front end cover far from the piezoelectric ceramic sheet. Herein, the ratio change processing refers to differentially changing the cross-sectional areas at the front and rear of a certain area. For example, in a certain area, the cross-sectional area at the head position is 30 mm, and the cross-sectional area at the tail position is 15 mm. After multi-stage such ratio changes, the amplitude output by the transducer can be increased. That is to say, even if the frequency is increased, its output amplitude can still remain at a relatively large value, achieving the effect of increasing the amplitude compared with traditional transducers. In addition, through multi-stage ratio change processing, it is also beneficial to disperse stress, avoid stress concentration at one place and cause fracture, and finally achieve the effect of increasing the output amplitude while reducing the stress. In specific applications, the transducer should be used together with the horn after being threadedly connected to achieve an increase in the output amplitude. However, based on the above design, the transducer in this embodiment will omit the horn and directly use the extended front end cover as the horn, that is, the transducer and the horn can be regarded as integrated. In this way, not only can a high output amplitude be ensured, but also the influence caused by the fracture of the screw connecting the transducer and the horn can be avoided. Table 1 shows the stress experimental data parameters of the existing transducer with a horn and the transducer of this application.

[0047] Table 1:

[0048]

[0049] Through experimental verification, compared with the existing structure, due to the integrated structure setting of the transducer of this application, the deformation is reduced, and the stress on the front end cover will gradually decrease, greatly improving the service life of the front end cover.

[0050] Furthermore, the transducer design method of this application also includes the opening of multiple notches. Among them, when performing finite element analysis, the maximum amplitude output point of the current transducer model can be obtained. Then, notches can be opened in the positive and / or negative directions of the maximum amplitude output point. It should be noted that the positive direction refers to the upper part of the maximum amplitude output point; similarly, the negative direction refers to the lower part of the maximum amplitude output point. Through the setting of the notches, the transducer will generate a rotational movement mode in addition to axial deformation during use, thereby forming a composite movement of the transducer and improving its output effect. In specific applications, the notch can be a through groove communicating with the inside of the front end cover, a groove not communicating with the inside of the front end cover, or both types of grooves can be used simultaneously. In addition, the opening shape of the notch can be diverse. For example, the notch can be an inclined groove opened along the arc surface of the front end cover, a straight groove opened along the arc surface of the front end cover, or both the inclined groove and the straight groove can be used simultaneously.

[0051] Preferably, the transducer design method of the present application further includes opening a plurality of through holes. Among them, the maximum amplitude output point of the transducer model is obtained through finite element analysis, and then a plurality of through holes are arranged at intervals at the maximum amplitude output point, thereby forming a "sonic supercooling" phenomenon, causing the air in the through holes to drop suddenly, playing a cooling role and extending the service life of the transducer. Specifically, the cross-sectional shape of the through hole can be circular, rectangular, oval, etc.

[0052] Furthermore, the transducer design method of the present application further includes detecting the output power of the transducer model. Specifically, the following formula is used for detection:

[0053] P = a * n * Va: the power coefficient of the piezoelectric ceramic sheet working mode; n: the number of piezoelectric ceramic sheets; V: the volume of the piezoelectric ceramic sheet. Among them, the value of a will be adjusted according to different materials used. Therefore, the value range of a is 0.1 - 9.9. In the case of the same material, the value of a can be divided into two situations. If the transducer model will work continuously for a long time, then a = 2.5; conversely, if the transducer model will work intermittently, then a = 4.0. Through this detection formula, it can be quickly known whether the designed transducer model can output the required power, greatly improving the product design efficiency.

[0054] In another embodiment, the front end cover and the rear end cover of the transducer can be designed as a symmetrical structure. That is to say, the existing rear end cover structure is omitted, and then the above-mentioned front end cover structure of the present application is synchronously arranged at the rear end cover position. Since the transducer of the present application can output the same frequency at the front end cover and the rear end cover, thereby realizing the bidirectional output of the transducer. In a specific use scenario, changing the traditional single output to a bidirectional output will double the production capacity and greatly improve the production efficiency.

[0055] In summary, increase the length of the front end cover. At the same time, by adjusting the length and / or radian (diameter) of the front end cover, the redesigned transducer outputs the required frequency and power, and the redesigned transducer and the transducer designed with the conventional half-wavelength design achieve the same frequency output when using the same material. Among them, the redesigned transducer has a longer front end cover space, which is not only convenient for the subsequent addition of piezoelectric ceramic sheets, but also conducive to the connection with other components, changing the transducer from a half-wavelength design to a double-wavelength design, overcoming the problem of insufficient length of the existing half-wavelength designed transducer after the frequency is increased, and thus realizing the high-frequency and high-power output of the transducer.

[0056] Embodiment 2

[0057] In this embodiment, the design method in Embodiment 1 will be adopted for the transducer design, and the specific situation is introduced as follows: A transducer includes a first end cap 1, a second end cap 2, a plurality of ceramic parts 3, a plurality of pole pieces 4, and a connecting member 5. The plurality of ceramic parts 3 and the plurality of pole pieces 4 are arranged alternately in sequence, that is, one pole piece 4 is arranged between two ceramic parts 3. Similarly, one ceramic part 3 is arranged between two pole pieces 4; the pole piece 4 is externally connected to a power supply; the first end cap 1 and the second end cap 2 are respectively located at both ends after the plurality of ceramic parts 3 and the plurality of pole pieces 4 are assembled, and the first end cap 1 and the second end cap 2 are connected by the connecting member 5, and the plurality of ceramic parts 3 and the plurality of pole pieces 4 are sleeved on the connecting member 5. In this embodiment, the transducer further includes an insulating member (not marked in the figure). The insulating member is sleeved on the first end cap 1, and both the ceramic part 3 and the pole piece 4 are sleeved on the outer surface of the insulating member. That is to say, the insulating member will be located between the ceramic part 3 and the first end cap 1, and the insulating member is also located between the pole piece 4 and the first end cap 1.

[0058] In this embodiment, the first end cap 1 is used as the front end cap, the second end cap 2 is used as the rear end cap, and the ceramic part 3 is used as the piezoelectric ceramic sheet. In addition, based on the design of double wavelength, the length of the first end cap 1 is longer than that in the case of half wavelength design.

[0059] Furthermore, a variable ratio area 11 with multiple connected segments is formed on the first end cap 1. The multiple variable ratio areas 11 are connected and extended in sequence in the direction away from the second end cap 2. Through the setting of the multiple variable ratio areas 11, the stress received by the first end cap 1 will not be concentrated at one place, realizing the distribution of stress and improving the problem of the first end cap 1 breaking. In addition, it is also beneficial to increase the output amplitude. In specific applications, the variable ratio area 11 includes a small-diameter section 111 and a large-diameter section 112. When multiple variable ratio areas 11 are connected, the adjacent connections of the small-diameter section 111 or the large-diameter section 112 all have a change in diameter. For example, the small-diameter section 111 is adjacent to the large-diameter section 112, and the large-diameter section 112 is connected to the small-diameter section 111 in the next variable ratio area 11. That is to say, the small-diameter section 111 and the large-diameter section 112 are arranged alternately.

[0060] Furthermore, the first end cap 1 is also provided with a plurality of composite grooves 12. The plurality of composite grooves 12 are spaced apart on the outer surface of the first end cap 1. By providing the composite grooves 12, the output of the composite motion of the first end cap 1 is realized. That is to say, the first end cap 1 can output axial power and can also output rotational power. The composite groove 12 in this embodiment serves as the notch in the first embodiment. Specifically, the composite grooves 12 can be distributed at the positive and / or negative positions of the maximum amplitude output point. The composite groove 12 can be a through groove communicating with the inside of the first end cap 1, or a groove not communicating with the inside of the first end cap 1, or two types of grooves can be used synchronously. In addition, the shape of the composite groove 12 can be diverse. For example, the composite groove 12 is an inclined groove obliquely provided along the arc surface of the first end cap 1, or a straight groove provided straight along the arc surface of the first end cap 1, or an inclined groove and a straight groove are used synchronously. It should also be noted that the composite grooves 12 can be provided at multiple places on the same first end cap 1.

[0061] Furthermore, the first end cap 1 is also provided with a plurality of cooling holes 13. Among them, the plurality of cooling holes 13 are spaced apart on the outer surface of the first end cap 1. In specific applications, the cooling holes 13 are provided at the maximum amplitude output point, so that a "sonic supercooling" phenomenon is formed at this place, and then the heat generated at this place can be quickly taken out. Specifically, the cooling hole 13 has a through-hole structure, and its cross-sectional shape can be circular, rectangular, oval, etc.

[0062] Embodiment 3

[0063] The difference between this embodiment and the second embodiment is that the transducer in this embodiment has a bidirectional output function, that is, the second end cap 2 and the connecting member 5 are cancelled, and ceramic parts 3, pole pieces 4 and the first end cap 1 structure of the same structure are extended in this direction. In this way, the output points of the transducer are increased, which is beneficial to improving the production efficiency.

[0064] The above are only the embodiments of the present invention and are not used to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention should be included within the scope of the claims of the present invention.

Claims

1. A transducer design method, characterized in that, Including: Set the required frequency and power; Increase the length of the front end cover. Based on the length of the front end cover at half wavelength, increase the length of the front end cover; Adjust the length and / or radian of the front end cover so that its output frequency matches the required frequency; among them, both the length and the radian are inversely proportional to the frequency.

2. The transducer design method according to claim 1, wherein After increasing the length of the front end cover, increase the number of piezoelectric ceramic pieces to achieve the required power; It also includes checking the output power of the transducer model, and its checking formula is: P = a * n * V a: The power coefficient of the working mode of the piezoelectric ceramic piece, where a = 0.1 - 9.9; n: The number of piezoelectric ceramic pieces; V: The volume of the piezoelectric ceramic piece.

3. The transducer design method according to claim 2, wherein Group multiple piezoelectric ceramic pieces and set intervals between groups.

4. The transducer design method according to claim 1, wherein Obtain the maximum amplitude output point of the transducer model through finite element analysis, and open multiple notches at intervals in the forward and / or reverse directions of the maximum amplitude output point.

5. The transducer design method according to claim 4, characterized in that, The notches are opened in at least one of the form of inclined slots and straight slots.

6. The transducer design method according to claim 1, characterized in that, Obtain the maximum amplitude output point of the transducer model through finite element analysis, and open through holes at the maximum amplitude output point.

7. The transducer design method according to any one of claims 1 - 6, characterized in that, It also includes: Symmetrically set the front end cover and the rear end cover to form a two-way output.

8. A transducer obtained by using the design method according to any one of claims 1-7, characterized in that, Including: A first end cover (1), a second end cover (2), a plurality of ceramic parts (3), a plurality of pole pieces (4) and a connecting piece (5). The first end cover (1) and the second end cover (2) are connected by the connecting piece (5), and the plurality of ceramic parts (3) and the plurality of pole pieces (4) are arranged alternately between the first end cover (1) and the second end cover (2).

9. The transducer according to claim 8, characterized in that: The first end cover (1) has multiple variable ratio regions (11), and the multiple variable ratio regions (11) extend away from the ceramic part (3) and are connected in sequence.

10. The transducer according to claim 8, characterized in that: A plurality of composite slots (12) are spaced apart on the surface of the first end cover (1).

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