KR20210074695A - Heating element using ultrasonic vibration - Google Patents

Abstract

An object of the present invention is to provide a heating element using ultrasonic vibration by using a piezoelectric ultrasonic transducer. The present invention provides a heating element using a piezoelectric ultrasonic transducer. According to the present invention, when a voltage that can cause ultrasonic vibration on the piezoelectric ultrasonic transducer at a resonant frequency is applied to a piezoelectric element structure, a vibration plate generates ultrasonic vibration so that high heat is generated.

Description

Heating element using ultrasonic vibration {HEATING ELEMENT USING ULTRASONIC VIBRATION}

The present invention relates to a heating element using ultrasonic vibration. Specifically, the present invention relates to a heating element using a piezoelectric element structure using ultrasonic vibration.

Ultrasonic transducer is an electronic component that converts AC energy exceeding 20 kHz, exceeding the audible frequency range, into another type of output signal such as mechanical vibration of the same frequency, mainly due to the piezoelectricity effect or magnetostriction. apply the effect. In particular, piezoelectric ultrasonic transducers that convert electrical signals into mechanical vibrations generally use quartz having high stability as a piezoelectric material, and are manufactured using various materials such as PZT series thin films or thin plates.

While the piezoelectric ultrasonic transducer has various advantages such as excellent frequency response, fast response speed, high output signal, and miniaturization, a separate amplifier is required due to the high impedance properties of the piezoelectric material and has high durability. It has a disadvantage that it is difficult to form a piezoelectric material. In addition, it may have a function of a piezoelectric transmitter as an actuator for generating ultrasonic vibration from an applied electric signal and a function of a receiver as a sensor for recognizing a physical ultrasonic signal as an electric signal. It is being used in various industrial fields, such as a sonar that recognizes distance and images in the water by using these characteristics, a non-destructive testing device that detects the internal structure without destroying the specimen, and a micro speaker for sound realization.

An object of the present invention is to provide a heating element using ultrasonic vibration using a piezoelectric ultrasonic transducer.

A heating element using ultrasonic vibration according to an embodiment of the present invention includes a piezoelectric element structure arranged in n x m (n, m is an integer of 2 or more); and a diaphragm respectively disposed on the upper surface of the piezoelectric element structure, wherein the piezoelectric element structures are connected in parallel to each other, and the diaphragm has a size capable of generating ultrasonic vibration at a resonant frequency, and causes ultrasonic vibration at the resonant frequency. When a high voltage is applied to the piezoelectric element structure, the diaphragm generates ultrasonic vibration while generating high heat.

The piezoelectric element structure may include a lower planar electrode; a sheet of piezoelectric material on the lower electrode; and an upper planar electrode on the sheet of piezoelectric material.

The piezoelectric element structure may include a lower planar electrode; a sheet of piezoelectric material on the lower electrode; and a plurality of structures including upper planar electrodes on the piezoelectric material sheet are stacked.

The plurality of piezoelectric element structures are arranged at regular intervals from each other.

The diaphragm includes a concave-convex structure formed on one surface of the diaphragm, and the specific surface area of the diaphragm is increased by the concave-convex structure to improve ultrasonic signal output performance, thereby improving heat generation performance.

The concave-convex structure includes a plurality of concavities and convexities, and the plurality of concavities and convexities are arranged at regular intervals from each other.

It is preferable that the unevenness has a nano size.

The present invention provides a heating element using a piezoelectric ultrasonic transducer. According to the present invention, when a voltage capable of causing ultrasonic vibration at a resonant frequency is applied to the piezoelectric element structure to the piezoelectric ultrasonic transducer, the diaphragm generates ultrasonic vibration while generating high heat.

1 shows a plan view of a diaphragm of a piezoelectric ultrasonic transducer according to an embodiment of the present invention.
2 is a cross-sectional side view of a diaphragm of a piezoelectric ultrasonic transducer according to an embodiment of the present invention.
3 shows a plan view of an additional diaphragm of a piezoelectric ultrasonic transducer according to an embodiment of the present invention.
4A shows a cross-section of a piezoelectric element structure according to an embodiment of the present invention.
4B shows a piezoelectric element structure in which two piezoelectric bodies are stacked.
5 is a plan view of a heating element using ultrasonic vibration according to an embodiment of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS Various embodiments are now described with reference to the drawings, wherein like reference numerals are used to refer to like elements throughout. In this specification for purposes of explanation, various descriptions are presented to provide an understanding of the present invention. However, it is apparent that these embodiments may be practiced without these specific descriptions. In other instances, well-known structures and devices are presented in block diagram form in order to facilitate describing the embodiments.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. Since the present invention can have various changes and can have various forms, specific embodiments are illustrated in the drawings and described in detail in the text. However, this is not intended to limit the present invention to the specific disclosed form, it should be understood to include all modifications, equivalents and substitutes included in the spirit and scope of the present invention. In describing each figure, like reference numerals have been used for like elements.

The terms used in the present application are used only to describe specific embodiments and are not intended to limit the present invention. The singular expression includes the plural expression unless the context clearly dictates otherwise. In the present application, terms such as “comprise” or “have” are intended to designate that a feature, step, operation, component, part, or combination thereof described in the specification is present, and includes one or more other features or steps. , it should be understood that it does not preclude the possibility of the existence or addition of , operation, components, parts, or combinations thereof.

The present invention provides a heating element using a piezoelectric ultrasonic transducer. According to the present invention, when a voltage is applied to the piezoelectric element structure to cause ultrasonic vibration at a resonant frequency in the piezoelectric ultrasonic transducer, the diaphragm generates ultrasonic vibration while generating high heat.

A heating element using ultrasonic vibration according to an embodiment of the present invention includes a piezoelectric element structure arranged in n x m (n, m is an integer of 2 or more); and a diaphragm respectively disposed on an upper surface of the piezoelectric element structure.

The piezoelectric element structure is a part that changes into mechanical deformation when an electrical signal is received by the piezoelectric effect, and the diaphragm vibrates by the mechanical deformation of the piezoelectric element structure.

The piezoelectric element structure can be seen in FIGS. 4A and 4B , respectively.

4A shows a cross-section of a piezoelectric element structure according to an embodiment of the present invention. As shown in Figure 4a, the piezoelectric element structure, the lower planar electrode (E1); a sheet of piezoelectric material (PZ) on the lower electrode; and an upper planar electrode E2 on a sheet of piezoelectric material. A diaphragm VPL may be attached to the upper surface of the piezoelectric element structure, whereby the diaphragm vibrates due to deformation of the piezoelectric element.

The piezoelectric element structure includes a diaphragm on its upper surface, and in this case, the diaphragm has a size capable of generating ultrasonic vibrations at a resonant frequency. As the size of the diaphragm decreases, the resonant frequency increases. In general, when the resonant frequency is higher than 20 kHz, the diaphragm generates ultrasonic vibration and the diaphragm vibrates and dissipates heat. Accordingly, the size of the diaphragm may be controlled to have a resonant frequency of 20 kHz or higher.

The diaphragm has a size capable of generating ultrasonic vibrations at a resonant frequency, and when a voltage is applied to the piezoelectric element structure to generate ultrasonic vibrations at the resonant frequency, the diaphragm generates ultrasonic vibrations and high heat is generated.

Meanwhile, two or more piezoelectric bodies may be stacked in the piezoelectric element structure as shown in FIG. 4B , and FIG. 4B illustrates an example in which two or more piezoelectric bodies are stacked. As shown in Figure 4b, the piezoelectric element repellent is a first electrode (E1); a first piezoelectric material sheet PZ1; a second electrode E2; a second piezoelectric material sheet PZ2; and a third electrode E3 , and output may be further increased by such a stacked structure. In this case, when a piezoelectric layer of the same thickness is compared by forming a laminated structure, if a laminated structure is used rather than a single layer, the electric field effect is increased, so that an effect of improving the output can be obtained.

As the piezoelectric material sheet, one formed of a piezoelectric ceramic or a ceramic/polymer composite is used.

In the present invention, a plurality of the above-described piezoelectric element structures may be arranged as shown in FIG. 5 . 5 is a plan view of a heating element using ultrasonic vibration according to an embodiment of the present invention.

As shown in FIG. 5 , in the heating element using ultrasonic vibration according to an embodiment of the present invention, n x m piezoelectric element structures are arranged. In this case, n and m are integers of 2 or more. The plurality of piezoelectric element structures are arranged at regular intervals from each other. In the embodiment of FIG. 5, it is an example of a state in which 3 x 3 piezoelectric element structures are arranged.

Each of the piezoelectric element structures each includes a diaphragm on its upper surface, which has already been described above.

The piezoelectric element structures 200 are disposed on the substrate 100 at regular intervals from each other, and the piezoelectric element structures 200 are connected to each other in parallel. This parallel connection has an advantage that high heat can be generated even at the same operating voltage frequency.

In addition, in an embodiment of the present invention, the diaphragm VPL includes a concave-convex structure formed on one surface of the diaphragm, and the specific surface area of the diaphragm is increased by the concave-convex structure to improve ultrasonic signal output performance, thereby generating heat Performance can be improved.

1 is a plan view of a diaphragm of a piezoelectric ultrasonic transducer according to an embodiment of the present invention, and FIG. 2 is a side cross-sectional view of the diaphragm of a piezoelectric ultrasonic transducer according to an embodiment of the present invention. 3 shows a plan view of an additional diaphragm of a piezoelectric ultrasonic transducer according to an embodiment of the present invention.

As shown in FIGS. 1 and 2 , the diaphragm includes a concave-convex structure, and the concave-convex structure includes a plurality of concavo-convex structures.

1 and 2 show that the irregularities have a rectangular shape, and FIG. 3 shows a cylindrical shape. The unevenness may be in the form of a polygonal column or cylinder, and may also be in the form of a polygonal horn or cone. In order to adjust the size of the output (the intensity of heat), it may be controlled in various forms depending on the intended use.

The improvement of the ultrasonic signal output performance in the diaphragm is obtained by such a concave-convex structure. In general, the diaphragm is made of a soft material such as metal (aluminum, etc.), and these materials have low durability, so when vibration occurs at a high frequency, deformation occurs little by little. This deformation causes a slight deviation from the design structure originally intended by the designer, thereby causing a problem in that the ultrasonic signal output performance of the transducer is changed. In order to solve this problem, the present invention includes a concave-convex structure.

Due to the unevenness of the uneven structure, in particular, as the number of unevenness increases, the rigidity of the diaphragm is improved. In addition, since the specific surface area of the diaphragm is increased due to the concave-convex structure, the signal output is much larger than that without the concave-convex structure. As a result, the output is ultimately increased and the amount of heat generated is also improved.

This concave-convex structure includes a plurality of concavities and convexities 13 . It is preferable that the plurality of irregularities 13 are arranged at regular intervals from each other. Since the plurality of irregularities are arranged at regular intervals from each other, advantages such as improvement of ultrasonic signal output performance may occur uniformly throughout the diaphragm. In addition, since more irregularities are more advantageously arranged in the same area, the size of the irregularities is preferably nanoscale. Thereby, it becomes possible to arrange|position the largest number of unevenness|corrugation uniformly in the same area.

On the other hand, making such a concave-convex structure can be obtained by individually printing or depositing the concave-convex structure on the diaphragm. In addition, in order to easily make the concave-convex structure, it is preferable to pattern-etch the surface of the diaphragm itself.

Although the above has been described with reference to the preferred embodiment of the present invention, those skilled in the art can variously modify and change the present invention without departing from the spirit and scope of the present invention as set forth in the claims below. You will understand that you can.

Claims (7)

a piezoelectric element structure arranged in nxm (n, m is an integer greater than or equal to 2); and
and a diaphragm respectively disposed on the upper surface of the piezoelectric element structure,
The piezoelectric element structures are connected in parallel to each other,
The diaphragm has a size capable of generating ultrasonic vibrations at a resonant frequency, and when a voltage is applied to the piezoelectric element structure to generate ultrasonic vibrations at the resonant frequency, the diaphragm generates ultrasonic vibrations while generating high heat,
Heating element using ultrasonic vibration.
The method of claim 1,
The piezoelectric element structure,
lower planar electrode; a sheet of piezoelectric material on the lower electrode; and an upper planar electrode on the sheet of piezoelectric material;
Heating element using ultrasonic vibration.
The method of claim 1,
The piezoelectric element structure,
lower planar electrode; a sheet of piezoelectric material on the lower electrode; and a structure in which a plurality of structures including an upper planar electrode on the piezoelectric material sheet are stacked,
Heating element using ultrasonic vibration.
The method of claim 1,
The plurality of piezoelectric element structures are arranged at regular intervals from each other,
Heating element using ultrasonic vibration.
The method of claim 1,
The diaphragm includes a concave-convex structure formed on one surface of the diaphragm, and the specific surface area of the diaphragm is increased by the concave-convex structure to improve ultrasonic signal output performance to improve heat generation performance,
Heating element using ultrasonic vibration.
6. The method of claim 5,
The concave-convex structure includes a plurality of irregularities,
The plurality of irregularities are arranged at regular intervals from each other,
Heating element using ultrasonic vibration.
6. The method of claim 5,
The irregularities are nano-sized,
Heating element using ultrasonic vibration.

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