Wearable device for transdermal product supply

Abstract

The present invention includes a head (3) having an outer cavity (6) that resonantly houses two ultrasonic resonators (resonator 1, resonator 2). A first resonator (1) located further distally emits towards the skin at a first frequency, and a second resonator (2) located closer proximally emits parallel to the skin around the outer cavity (6) at a second frequency. One of the frequencies is high-frequency sonophoresis (HFS) and the other is low-frequency sonophoresis (LFS). The second resonator (2) includes an inner through-hole (7) to enable waves from the first resonator (1) to pass through. Waves from the second resonator (2) pass through the head (3), the inner through-hole (7), and the outer cavity (6), bounce off opposite regions of the head (3), and interfere with waves from the first resonator (1). The interference between the waves produces a static field that increases skin permeability, enabling a device of reduced size to be incorporated into a wearable device.

Description

Technical Field

[0001] This invention can be applied to the fields of health and personal care, and more specifically to the delivery of articles containing active substances, such as pharmaceuticals and cosmetics. More specifically, the object of this invention is a wearable device for the transdermal, non-invasive delivery of articles. Background Technology

[0002] There are different technologies and devices for the transdermal, non-invasive delivery of drugs with molecules that are quite large, such as insulin.

[0003] Therefore, the drug must pass through the stratum corneum of the patient's skin, which has low absorption capacity, especially for high molecular weight molecules such as insulin.

[0004] Human skin has a stratum corneum, which is composed of an outer layer of dead cells (keratinocytes) embedded in a lipid matrix. This makes it difficult for substances to diffuse through the stratum corneum, especially substances such as insulin whose molecular size is larger than that of skin pores.

[0005] In this sense, several techniques were initially developed, such as electrophoresis (voltages up to 150V) or iontophoresis with lower voltages.

[0006] Beginning in 1950, the benefits of ultrasound delivery were discovered, which involves applying ultrasound waves to a liquid in contact with the skin, containing substances to be delivered into the skin. Initially, high-frequency ultrasound delivery (HFS) was used to transfer corticosteroids at frequencies from 700 kHz to 10,000 kHz, achieving a transfer efficiency 10 times higher than without ultrasound. This was attributed to a stable cavitation effect, which creates oscillating bubbles within the stratum corneum of the lipid matrix, disrupting the stratum corneum layer to allow for better permeability of smaller molecules.

[0007] Beginning in the 1990s, research began on the mid-to-low frequency acoustic aperture effect after it was learned that the application of ultrasound cavitation effects could improve the transmission of certain substances through the skin, and that the effects related to liquid cavitation increased inversely with frequency. Studies of the effects of low frequencies (20-100kHz, low-frequency ultrasound delivery, LFS) were initiated, revealing that in LFS, lower frequencies resulted in greater permeability. This indicates that transient cavitation is the most important mechanism for improving skin permeability using LFS.

[0008] Since 1996, several studies on multi-frequency ultrasound induction—one frequency in the high-frequency field (HFS) and the other in the low-frequency field (LFS)—have been published, achieving satisfactory results in applying the HFS and LFS frequencies separately. However, a drawback is that for LFS frequency applications, the size of the transducer used to provide the LFS frequency wave increases as the frequency decreases and the intensity increases. Therefore, devices providing sufficiently high intensity are too large to be incorporated into wearable devices. In other words, the low-frequency ultrasound transducers used to achieve the required intensity are too large to be added to wearable devices. Summary of the Invention

[0009] This invention describes a device for non-invasive transdermal delivery of an article, which is wearable due to the combination of two ultrasonic resonators, for example, piezoelectric ones, housed in the same head, one at a distal position and the other at a proximal position, such that each resonator, in combination with the head configuration, defines a transducer, wherein one of the two resonators operates at an LFS frequency and the other at an HFS frequency. Similarly, the resonator at the proximal position has an internal aperture through which emissions from the other, more distal resonator can pass, such that the emissions from the two resonators interact to generate a static field, which increases the permeability effect for a given resonator size, thereby enabling a reduction in the size of the device to achieve predetermined performance.

[0010] With the device of the present invention, the product penetrates the stratum corneum by cavitation and opening pores, in a reversible manner without causing damage to the skin.

[0011] The device of the present invention may optionally have medical uses as will be explained later, but not exclusively.

[0012] Typically, according to existing technology, the thickness and size of a resonator are determined by its operating frequency and intensity. However, the device of this invention amplifies the generated wave to obtain a resonance peak at the desired frequency, particularly in the LFS frequency range, because its design emits the wavefront differently throughout the structure of its head, thereby providing a generated wave of the desired frequency and intensity, which, as previously mentioned, produces a static field with an amplified permeability effect in both LFS and HFS cases. All of this allows the device to be manufactured within a size suitable for forming part of a wearable device.

[0013] The device is configured to supply a wide variety of products. These products can be liquids with high or low density or viscosity, and they can also have a non-liquid texture such as gels, ointments, or creams. The device can be used for medical purposes, as both liquid and non-liquid products can contain medications such as insulin. Alternatively, the device can be configured to supply other types of products, such as cosmetics, which can be liquid or have a non-liquid texture, for example, creams, gels, ointments, etc., as described above.

[0014] The present invention has preferred exemplary embodiments in which the resonator located at the proximal end resonates at the LFS frequency and the resonator located at the distal end resonates at the HFS frequency, and in another preferred exemplary embodiment the opposite occurs, i.e., the resonator located at the proximal end resonates at the HFS frequency and the resonator located at the distal end resonates at the LFS frequency. Attached Figure Description

[0015] The foregoing and other advantages and features will be better understood from the following detailed description of several embodiments based on the accompanying drawings, which must be interpreted in an illustrative and non-limiting manner, wherein:

[0016] Figure 1 A schematic side view of the head of the device is shown.

[0017] Figure 2A and Figure 2B , Figure 2A A schematic cross-sectional side view illustrating the construction of a first exemplary embodiment of the device of the present invention is shown. Figure 2B A cross-sectional side view of the head is shown.

[0018] Figure 3A and Figure 3B , Figure 3A A schematic cross-sectional side view illustrating the construction of a second exemplary embodiment of the device of the present invention is shown. Figure 3B A cross-sectional side view of the head is shown. Detailed Implementation

[0019] Next, using the above Figures 1-3B The present invention provides a detailed description of preferred exemplary embodiments of wearable medical devices for universal transdermal delivery of articles, and is particularly, but not exclusively, intended for the delivery of drugs, more specifically, for the delivery of insulin, and enables the articles to penetrate the stratum corneum of the user’s skin by means of cavitation effect and by opening pores in a reversible and non-damaging manner.

[0020] like Figure 1As shown, the device of the present invention includes two ultrasonic resonators (1, 2), for example, these two ultrasonic resonators are piezoelectric type, and are mounted in the same head 3. The head 3 has a proximal region 4 intended to contact the user's skin, and a distal region 5 opposite to the proximal region 4 and thus away from the user's skin.

[0021] In the proximal region 4, the head 3 has an external cavity 6, which is intended to contain an ultrasound-conducting material during use. This material may be liquid or have a non-liquid texture such as an ointment, cream, or gel to prevent the presence of gas and thus enable the transmission of ultrasound waves from the head 3 to the skin. Generally, the ultrasound-conducting material conforms to the article to be applied, although this is not necessarily the case. In particular, the article may be deposited within the cavity 6 of the head 3, and then the head 3 is applied to the skin to bring the skin into contact with the article. Alternatively, the device may be applied to a reservoir of the article (not shown), such as a patch, which is arranged to be fixed (e.g., by adhesive) or simply superimposed on the user's skin. Another possibility, illustrated, is that the device additionally includes a supply element (not shown) removably or non-removably connected to the head 3 near the cavity 6 to supply the article, particularly according to a predetermined dose. The head 3 is preferably made of one or more biocompatible materials.

[0022] The resonators (1, 2) include a first resonator 1 located in the distal region 5 and thus unaffected by the cavity 6, and a second resonator 2 located in the proximal region 4, which, as described below, surrounds at least a portion of the cavity 6. The resonators (1, 2) are intended to emit narrowband ultrasonic waves and operate resonantly, each resonator operating at a predetermined frequency.

[0023] The first resonator 1 is shaped, for example, like a disk. When in use, the first resonator 1 emits ultrasonic radiation at a first frequency toward the user's skin, the ultrasonic radiation being approximately perpendicular to the direction toward the skin towards the cavity 6. The second resonator 2 is hollow. When in use, the second resonator 2 emits waves at a second frequency, i.e., the inner aperture 7 of the second resonator 2 allows waves of the first frequency to pass through without impacting the second resonator 2. Preferably, the inner aperture 7 is larger than the first resonator 1, such that all waves emitted by the first resonator 1 pass through the inner aperture 7 of the second resonator 2. The second resonator 2 can have a ring shape, regardless of whether it has a circular, square, or other type of generatrix, or a circular or other type of guideline. Preferably, it has a circular annular shape, i.e., a ring-shaped annulus or an annulus with a rectangular cross-section.

[0024] The first resonator 1 is superimposed on the second resonator 2, but is not contained by the second resonator 2; that is, the first resonator 1 is at a different height. This superposition ensures that the wave emitted by the first resonator 1 does not collide with the second resonator 2, but instead passes through the inner through-hole 7, as described above.

[0025] The cavity 6 of the head 3 corresponds to the portion at the height of the second resonator 2 and is surrounded by the second resonator 2. Therefore, the wave emitted by the second resonator 2 is substantially parallel to the skin and can amplify the penetrating effect of the first resonator 1.

[0026] The head 3 has a triple function: supporting the resonators (1, 2), providing physical continuity for the wave path, and inducing resonance at a first frequency and a second frequency, as described below. The head 3 is preferably made of a metal such as aluminum, or alternatively, of a biocompatible polymer material such as polypropylene. Preferably, the head 3 is a monolithic structure. The resonators (1, 2) are assembled into the head 3, which is configured such that once the resonators (1, 2) are assembled, the waves emitted by the resonators (1, 2) circulate through the head 3 without encountering gaseous material before leaving the head 3, thus preventing malfunction of the resonators (1, 2). For example, such as... Figure 2A , Figure 2B , Figure 3A and Figure 3B As shown, the head 3 includes a receiving portion 13 housed in the inner through-hole 7 of the second resonator 2, and the receiving portion 13 preferably occupies the peripheral portion of the inner through-hole 7. Preferably, the receiving portion 13 constitutes a component of the head 3.

[0027] As previously described, the second resonator 2 has an inner through-hole 7, for example, because it is equipped with the aforementioned annular shape and is mounted within the head 3 corresponding to the cavity 6, such that the cavity 6 also occupies the inner through-hole 7 along with the receiving portion 13 of the head 3. Therefore, firstly, the radiation emitted by the first resonator 1 towards the user's skin passes through the inner through-hole 7 and the cavity 6 and reaches the skin. Secondly, in the horizontal direction, the waves generated by the second resonator 2 do not escape from the head 3 to "infinity," but are emitted through the inner through-hole 7, thus traversing the head 3 and the cavity 6. Therefore, they collide, bounce off the relative area of ​​the head 3 itself, and since they are all generated in the horizontal direction, a static field is generated in the cavity 6 for the waves from the second resonator 2, which interacts with the waves from the first resonator 1. This, under resonant conditions, increases the effect on the skin in the area surrounded by the head 3 and the second resonator 2, further increasing the permeability of the affected skin area, and thus increasing the effectiveness of the supply. Therefore, it is possible to obtain the desired resonance and intensity conditions in such a small device for integration into wearable devices.

[0028] One of the two resonators (1, 2), the first resonator 1 or the second resonator 2, emits a frequency significantly lower than that emitted by the other resonator, which emits a higher frequency. This low frequency is in the typical LFS domain, i.e., the lowest ultrasonic domain, between approximately 20 kHz and 100 kHz. Values ​​close to 20 kHz, within the upper limit of human hearing, produce satisfactory results, although at the cost of auditory discomfort for the user. A frequency in an environment between 50 kHz and 60 kHz, around 55 kHz, has been selected as the preferred low frequency. Furthermore, the high frequency is in the typical HFS domain, for example, between approximately 1 MHz, 800 kHz, and 1200 kHz. The invention works satisfactorily when the first frequency is high and the second frequency is low, or vice versa.

[0029] In addition to the resonators (1, 2) and their configuration in the head 3 as described above, another feature of the device of the present invention is the resonance processing described below.

[0030] As previously stated, one of the resonators (1, 2) is intended to be supplied with an HFS frequency to emit ultrasonic waves at the HFS frequency and to resonate at the HFS frequency, while the other resonator (1, 2) is intended to be supplied with an LFS frequency to emit ultrasonic waves at the LFS frequency and to resonate at the LFS frequency. Each of the resonators (1, 2) has a fundamental vibration frequency according to certain vibration modes due to its construction, for example, in a thickness mode or in a radial mode.

[0031] For example, a cylindrical (disc) shaped solid resonator (1, 2) has a fundamental frequency in thickness mode that decreases as the resonator size increases and vice versa. For instance, a ceramic with a fundamental frequency of 4 MHz can have a thickness of 0.5 mm and a diameter of 6 mm, while a ceramic with a fundamental frequency of 2 MHz can have a thickness of 1 mm and a diameter of 6 mm, and a ceramic with a fundamental frequency of 1 MHz can have a thickness of 2 mm and a diameter of 10 mm. In other words, a disk-shaped resonator (1, 2) with reduced dimensions, like the first resonator 1, is suitable for achieving resonance at the HFS frequency in thickness mode without adaptation.

[0032] In order to operate at the LFS frequency in thickness mode, hollow resonators (1, 2) in the shape of a ring, such as the second resonator 2, must have a large size; however, this is unacceptable in wearable devices.

[0033] To address the aforementioned drawbacks, the present invention proposes two types of solutions as shown below, which will be described in detail in the following embodiments.

[0034] The first solution involves using a first resonator 1, which is solid, for example, disk-shaped, equipped with a fundamental frequency in the thickness mode within the HFS range, and equipped with a fundamental frequency in the thickness mode within the HFS range, as described below, so as to resonate at the LFS frequency. This includes components (8, 9, 10) in a head 3 intended to contact the first resonator 1, thus forming an assembly of first resonator 1 + head 3. This assembly has physical continuity and constitutes a transducer that resonates in a buckling mode at the LFS frequency when supplied, even if the LFS frequency is not the fundamental frequency of the first resonator 1 in the thickness mode. A second resonator 2, having a hollow shape such as a ring, may have a fundamental frequency in the thickness mode within the HFS range, such that it will resonate at the HFS frequency when supplied. According to... Figure 2A and Figure 2B The first example, which will be described in detail below, indicates the dimensions and features, supporting the explanation made in the first solution.

[0035] Alternatively, the second solution involves utilizing the fact that a second resonator 2, having a hollow shape such as a ring, possesses a fundamental frequency in the LFS range in radial mode, rather than in thickness mode, due to its size and structure. Therefore, when supplied with an LFS frequency, the second resonator 2 will resonate at the LFS frequency in radial mode. Furthermore, the first resonator 1, in a disk shape, will have a fundamental frequency in the HFS range in thickness mode due to its size, and when supplied with an HFS frequency, it will resonate at the HFS frequency. Figure 3A and Figure 3B The second example, which will be described in detail below, indicates the dimensions and features, supporting the explanation made in the second solution.

[0036] Example description

[0037] The device of the present invention has the ability to operate based on different operating types of the resonators (1, 2), such as the bending-transmission type (see Figure 2A and Figure 2B ) and transport - transport type (see Figure 3A and Figure 3B ).according to Figure 2A and Figure 2B For resonators (resonator 1, resonator 2) operating in a bending-transmission type, the diaphragm 8 in contact with the first resonator 1 is generally arranged as an integral part of the head 3. The diaphragm 8 is preferably made of metal and vibrates by bending. Additionally, the head 3 may include two protrusions (9, 10), one proximal protrusion 9 and the other distal protrusion 10, wherein the protrusions (9, 10) cooperate with the diaphragm 8 to resonate with the first resonator 1 in a bending mode at a predetermined LFS frequency. In the case of a transmission-transmission type, according to Figure 3A and Figure 3B No membrane 8 is required, although similarly, the head 3 may include a transmission disk 14 for transmitting vibrations.

[0038] The height of cavity 6 is related to the height of the second resonator 2 and is selected based on the amount of desired product that can be accommodated within cavity 6. A reduced height would require the user to frequently replace the product in cavity 6, while a higher height would lead to greater risks associated with managing larger quantities. According to a preferred exemplary embodiment, the height of cavity 6 is approximately 1-2 mm. In use, cavity 6 contains an ultrasonically conductive material to prevent the presence of gas and thus enable the transmission of ultrasound waves from head 3 to the skin. The ultrasonically conductive material can be a liquid or can have a non-liquid texture such as a cream, gel, ointment, etc., as long as it is ultrasonically conductive. In particular, the ultrasonically conductive material can be the product to be applied when it is precisely ultrasonically conductive. The device of the present invention can also be used to supply products having a non-liquid texture such as the aforementioned cream, gel, ointment, etc. For this purpose, the device of the present invention is first used with an ultrasonically conductive material to generate cavitation and open skin pores. Utilizing these effects, active products with a non-liquid texture, such as creams, gels, ointments, etc., can be applied and absorbed without using the device. The ultrasonically conductive material can be harmless.

[0039] As can be seen from the illustrative, non-limiting example, the head 3 has a cylindrical shape, an inverted "U" shaped cross-section, a diameter of about 25 mm, a height of about 2-10 mm (preferably 5-10 mm), and a cavity 6 with a height of about 2-3 mm and 3 mm.

[0040] To achieve sufficiently high sound pressure levels to facilitate the combined effects described above—namely, the combined effect of generating a sufficient number of cavitation bubbles and opening pores in the skin through implosion of these cavitation bubbles—it is more convenient to emit waves capable of producing high ultrasonic intensity, greater than 0.5 W / cm². 2 Preferably greater than 1W / cm 2 In this sense, above 1W / cm 2 The strength is considered sufficiently appropriate. To meet several legally mandated limits, and particularly to prevent the ultimate risk of skin damage, it is preferable to maintain a strength value of 1 W / cm². 2 and 2W / cm 2 between.

[0041] Two examples of the features of head 3 with two resonators (1, 2) are shown below, as follows: Figure 2A , Figure 2B , Figure 3A and Figure 3B As shown.

[0042] In both examples, head 3 is a monolithic structure made of aluminum. Alternatively, head 3 could be a monolithic structure made of polypropylene.

[0043] See Figure 2A , Figure 2B According to the first example, known as bend-transmission, it includes the following components:

[0044] The first resonator 1 is configured as a ceramic disk for power application, the ceramic disk having a variable thickness between 0.5 mm and 1 mm and a diameter of 6 mm, the ceramic disk having a fundamental frequency of 2 MHz or 4 MHz in thickness mode.

[0045] The second resonator 2 is configured as a ceramic ring with a rectangular cross-section and a circular guideline for power application. The ring has a thickness of 2 mm, an outer diameter of 20 mm and an inner diameter of 14 mm, and a fundamental frequency of 1 MHz in thickness mode.

[0046] The diaphragm 8 has a diameter of 11 mm and a variable thickness, and in order to vibrate together with the first resonator 1 in the flexural mode supplied by the first resonator 1, the diaphragm 8 is inserted between the first resonator 1 and the second resonator 2 and is in contact with the first resonator 1.

[0047] Cavity 6, which has a variable height and a diameter of 11 mm, is located on membrane 8.

[0048] Two protrusions (9, 10), one proximal protrusion 9 and the other distal protrusion 10, are provided. A diaphragm 8 is supported between the two protrusions, wherein the distal protrusion 10 has an outer diameter of 14 mm and an inner diameter of 8 mm, while the proximal protrusion 9 has an outer diameter of 11 mm and an inner diameter of 8 mm. The protrusions (9, 10) mate with the diaphragm 8 to resonate with the first resonator 1 at a predetermined LFS frequency of 55 kHz.

[0049] The head 3, which is used to fix the resonators (1, 2) and supply vibrations transmitted from the first resonator 1, is partially composed of a diaphragm 8 and a proximal protrusion 9 and a distal protrusion 10.

[0050] The receiving part 13, which constitutes part of the head 3, is received in the more peripheral area of ​​the inner through hole 7.

[0051] An adhesive layer 12, having a variable thickness, is located between the second resonator 2 and the head 3.

[0052] In the first example, the coupling "thickness" mode of the second resonator 2 is used to transmit resonant vibrations directly to the head 3 to which it is attached, wherein the resonant frequency of the second resonator 2, although slightly varying due to the wall thickness of the head 3, is essentially dependent on the shape and material of the second resonator 2. Similarly, the first resonator 1 is used as the supplier of the dominant frequency, which is the function of the features of the first resonator 1, as well as the configuration of the diaphragm 8 and the protrusions (9, 10), and in particular, the function of the overall bending of the first resonator 1, the bending mode of the first resonator 1 at 55 kHz.

[0053] In addition, see Figure 3A , Figure 3B According to the second example, known as the transport-transport type, it includes the following components:

[0054] The first resonator 1 is configured as a ceramic disk for power application, the ceramic disk having a thickness of 2 mm and a diameter of 10 mm, and having a dominant oscillation frequency of 1 MHz in thickness mode.

[0055] The second resonator 2, which is made of ceramic and used for power application, is configured as a ring with a rectangular cross-section and a circular guideline. The ring has a thickness of 2 mm, an outer diameter of 20 mm, and an inner diameter of 14 mm, and has a radial vibration dominant frequency of 55 kHz.

[0056] The transmission disk 14, having a diameter of 11 mm and a variable thickness, is arranged on the first resonator 1 in order to receive the vibration of the first resonator 1 and transmit the vibration from the first resonator 1 to the cavity 6.

[0057] Cavity 6, which has a variable height of approximately 3.5 mm and a diameter of 11 mm, is located above the transfer disk 14.

[0058] The head 3 is used to secure the resonators (1, 2) and is partially composed of the transmission disk 14, which receives vibrations from the first resonator 1 by transmission.

[0059] The receiving portion 13 forms part of the head 3 and is intended to be received in the inner through hole 7.

[0060] In the second example, the first radial mode of the second resonator 2 is used to excite the flexural mode of the head 3 at a low frequency, particularly the flexural mode of the receiving portion 13. The first radial mode of the second resonator 2 is transmitted radially towards the wall of the head 3 to which the second resonator 2 is attached. The final frequency of the second resonator 2, together with the head 3, is a function of the overall flexural curvature of the second resonator 2; in this case, the final frequency is 55 kHz. Furthermore, the first resonator 1 operates through the direct transmission of the thickness mode at the HFS frequency.

[0061] In the second example, diaphragm 8 is not included; the excitation wave is directly transmitted from resonators (1, 2) to cavity 6, which differs from the first example. The first example combines the diaphragm 8, which vibrates by bending, to achieve resonance at the LFS frequency, such as 55 kHz, in both the first resonator 1 and diaphragm 8, when the second resonator 2 emits at an HFS, such as 1-3 MHz. Conversely, in the second example, the emission and resonant frequencies of the first resonator 1 are similar and close to 1 MHz, resulting in only transmission rather than bending. Therefore, this model is called transmission-transmission because there is a direct realization of transmission for both frequencies. In both examples, the first and second frequencies have been interchanged: in the first example, the first frequency is LFS and the second frequency is HFS, while in the second example, the opposite is true.

[0062] For each of the two examples, in general, for any embodiment of the invention, it is envisioned that the head 3 may be made of a metal such as aluminum or, alternatively, a biocompatible material such as a polymer, for example, polypropylene.

Claims

1. A wearable device for supplying transdermal products, comprising: Head (3), the head (3) comprising: The proximal region (4) is close to the user's skin during use. The distal region (5), which is far from the user's skin, and An outer cavity (6) is defined in the proximal region (4) and is oriented toward the user's skin during use; A first resonator (1), which is housed in the distal region (5) of the head (3), is used to resonate at a first frequency and to emit ultrasound to the user's skin at the first frequency; A second resonator (2), which is housed in the proximal region (4) of the head (3), is used to resonate at a second frequency and emit ultrasound at the second frequency in a direction parallel to the skin. One of the first frequency and the second frequency is a high-frequency ultrasound induction (HFS) frequency and the other is a low-frequency ultrasound induction (LFS) frequency, wherein the head (3) is configured such that the wave emitted by the resonator (1, 2) circulates through the head (3) without encountering gaseous material before leaving the head (3); The second resonator (2) is characterized in that it includes an inner through hole (7) so that waves from the first resonator (1) can pass through without impacting the second resonator (2). The portion of the cavity (6) of the head (3) corresponding to the height of the second resonator (2) is surrounded by the second resonator (2), and Waves from the second resonator (2) are guided through the head (3), the inner through-hole (7), and the outer cavity (6) to bounce off the head (3) in relative position and interfere with waves from the first resonator (1).

2. The apparatus according to claim 1, wherein, The LFS frequency mentioned therein falls within the range of 50Hz-60Hz.

3. The apparatus according to any one of claims 1-2, wherein, The HFS frequency mentioned above is within the range of 800-1200Hz.

4. The apparatus according to any one of claims 1-3, wherein, The first resonator (1) has a disk shape.

5. The apparatus according to any one of claims 1-4, wherein, The second resonator (2) has a ring shape.

6. The apparatus according to any one of claims 1-5, wherein, Together with the head (3), the first resonator (1) resonates at the LFS frequency and the second resonator (2) resonates at the HFS frequency.

7. The apparatus according to claim 6, wherein, The second resonator (2) has a ring shape and the ring shape has a fundamental frequency of vibration in the HFS range in the thickness mode, so as to resonate in the thickness mode at the HFS frequency when supplied as the HFS frequency. The first resonator (1) has a disk shape and the disk shape has a fundamental frequency of vibration in the HFS range in the thickness mode. The head also includes at least one component (8, 9, 10) in contact with the first resonator (1) to form an assembly with physical continuity consisting of the first resonator (1) and the head (3), which constitutes a transducer with a fundamental frequency in the LFS range in the flexion mode.

8. The apparatus according to claim 7, wherein, The components (8, 9, 10) include a diaphragm (8) that vibrates by bending, the diaphragm (8) being inserted between the first resonator (1) and the second resonator (2) and in contact with the first resonator (1).

9. The apparatus according to claim 8, wherein, The components (8, 9, 10) also include two protrusions (9, 10), one of which is a proximal protrusion (9) and the other is a distal protrusion (10), and the membrane (8) is supported between the proximal protrusion (9) and the distal protrusion (10).

10. The apparatus according to any one of claims 1-5, wherein, The first resonator (1) resonates at the HFS frequency, and the second resonator (2) resonates at the LFS frequency.

11. The apparatus according to claim 10, wherein, The first resonator (1) has a disk shape and the disk shape has a fundamental frequency in the HFS range in the thickness mode so as to resonate at the HFS frequency in the thickness mode when supplied at the HFS frequency; and the second resonator (2) has a ring shape and the ring shape has a fundamental frequency in the LFS range in the radial mode so as to resonate at the LFS frequency in the radial mode when supplied at the LFS frequency.

12. The apparatus according to claim 11, wherein, The head (3) also includes a transmission disk (14) disposed on the first resonator (1) to transmit vibrations from the first resonator (1) to the cavity (6) via transmission.

13. The apparatus according to any one of claims 1-12, wherein, The head (3) is composed of a single monolithic structure.

14. The apparatus according to any one of claims 1-13, wherein, The head (3) is made of a metal material or a biocompatible polymer material, wherein the metal material is preferably aluminum and the biocompatible polymer material is preferably polypropylene.

15. The apparatus according to any one of claims 1-14, wherein, The head (3) includes a receiving portion (13) that occupies at least a portion of the inner through hole (7) of the second resonator (2).

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