KR102818845B1 - A Ultrasonic Transducer Assembly - Google Patents

Abstract

A piezoelectric transducer assembly for generating ultrasonic waves according to one embodiment of the present invention comprises: a flat piezoelectric vibrator having piezoelectric ceramics attached to its upper and lower surfaces respectively; a horn provided on the piezoelectric vibrator to generate ultrasonic waves by vibration; a vibration plate frame provided between the piezoelectric ceramics to support both ends of the piezoelectric vibrator and to vibrate in a resonance mode while minimizing vibration displacement interference of the piezoelectric vibrator and transmitting an electrical signal; and a fixed plate provided on an upper end of the vibration plate frame to fix one surface of the vibration plate frame.

Description

{A Ultrasonic Transducer Assembly}

The present invention relates to a piezoelectric transducer assembly for generating ultrasonic waves. The present invention relates to a piezoelectric transducer assembly for generating ultrasonic waves, which comprises a bimorph-type piezoelectric vibrator having a flat plate to which piezoelectric ceramics are attached, and a vibration plate frame that vibrates at a resonant frequency similar to that of the piezoelectric vibrator is added to both ends of the piezoelectric vibrator so as to improve the sound quality of the emitting portion without restricting the vibration.

Conventional ultrasonic transducers are largely divided into piezoelectric element type and electrostatic capacitance type. When an electrical pulse is applied to both types, ultrasonic waves corresponding to the resonant frequency are emitted. When receiving ultrasonic waves, the vibration of the element caused by external ultrasonic waves is converted into an electrical signal and the amplified signal is used.

In the case of a typical ultrasonic transducer, when the vibrator vibrates freely, the part where the displacement of the vibrator is minimal is fixed to another fixed body with an adhesive, and since the vibration amplitude of the vibrator is too small, a horn is attached to the center to obtain an acoustic vibration effect through the vibration generated by the movement of the horn.

However, ultrasonic transducers using conventional technology had the following problems. In conventional transducers, the + and - power supply parts to which the power supply is connected were exposed to the air, making them vulnerable to moisture and humidity.

In addition, in order to increase the frequency of the ultrasonic transducer, the size of the ceramic must be reduced, but as the size decreases, the sound pressure decreases, making it difficult to increase both the frequency and sound pressure at the same time.

Therefore, in order to solve the above problem, the known prior art patent No. 10-2023-0060677 discloses a piezoelectric vibration unit (20) that generates vibration when an electric signal is applied, a horn (30) that generates ultrasonic waves by vibration, an elastic body (10) formed in a bar shape and connected to the piezoelectric vibration unit (20) at one end and the horn (30) at the other end, and a fixing plate (50) that fixes the elastic body (10). However, when the piezoelectric vibration unit (20) vibrates, the elastic body (10) generates a longitudinal resonance frequency. For example, a vibration with an intensity of about 40 kHz is generated in a piezoelectric vibration unit (20) having a disk shape of about 8 mm. Therefore, in order to generate a resonance frequency of 40 kHz in the elastic body (10), there arises a problem that the length of the bar-shaped elastic body (10) becomes unnecessarily large.

In addition, there is a problem of manufacturing cost and complicated manufacturing process required to array multiple disc-shaped piezoelectric vibratory units (20) by electrically connecting them one by one, and there is the inconvenience of having to replace the entire piezoelectric vibrator unit (20) if one of the multiple disc-shaped piezoelectric vibratory units (20) malfunctions.

Accordingly, a technology for assembling a piezoelectric transducer for generating ultrasonic waves that is simple in manufacturing process and can improve the size of sound pressure regardless of the length of the elastic rods by attaching multiple elastic rods and horns to a single flat piezoelectric vibrator so that the same signal of ultrasonic waves can be generated simultaneously from multiple horns with a single electrical signal has become necessary.

Referring to Fig. 2 (a) and Fig. 3 (a), the piezoelectric transducer assembly for ultrasonic generation in the existing development stage has both ends of the piezoelectric vibrator fixed to one frame, so vibration constraint occurs in the fixed piezoelectric vibrator portion, resulting in a problem of reduced speaker sound quality.

Therefore, a piezoelectric transducer assembly technology for ultrasonic generation that can improve vibration characteristics and enhance speaker sound quality has become necessary.

Korean Publication Patent No. 10-2023-0060677

The purpose of the present invention is to provide a piezoelectric transducer assembly for generating ultrasonic waves, which can improve the quality of sound without vibration constraints by attaching a plurality of elastic rods and horns to a single flat piezoelectric vibrator and arranging them so that the same signal of ultrasonic waves can be simultaneously generated from a plurality of horns with a single electrical signal, and by adding a vibration plate frame that vibrates at a resonant frequency similar to that of the piezoelectric motor to both ends of the piezoelectric vibrator.

In addition, the purpose is to provide a piezoelectric transducer assembly for generating ultrasonic waves that is waterproof by separating the emitting part where negative pressure is generated and the power supply part where power is supplied, and that is configured with multiple modular piezoelectric vibrators so that they can be selectively separated for easy maintenance.

The problems to be solved by the present invention are not limited to the problems mentioned above, and other problems to be solved by the present invention that are not mentioned herein will be clearly understood by a person having ordinary skill in the art to which the present invention belongs from the description below.

A piezoelectric transducer assembly for generating ultrasonic waves according to one embodiment of the present invention may include a flat piezoelectric vibrator having piezoelectric ceramics attached to its upper and lower surfaces respectively, a horn provided at one end of the piezoelectric vibrator and generating ultrasonic waves by vibration, a vibration plate frame provided between the piezoelectric ceramics and supporting both ends of the piezoelectric vibrator to minimize vibration displacement interference of the piezoelectric vibrator and transmit electrical signals while vibrating in a resonance mode, and a fixed plate provided at an upper end of the vibration plate frame and fixing one surface of the vibration plate frame.

According to one embodiment of the present invention, the vibration plate frame may be formed in the shape of a single long flat plate in the longitudinal direction, and may be characterized in that a fixed area portion fixedly supported by the fixed plate and an elastic area portion elastically supported by coming into contact with the piezoelectric vibrator are repeatedly formed at preset intervals.

According to one embodiment of the present invention, the length of the elastic region may be configured to be less than or equal to the maximum length of the piezoelectric vibrator.

The shape of the vibration plate frame according to one embodiment of the present invention may be characterized by being configured as one of a T-shape, an I-shape, and an H-shape.

A piezoelectric transducer assembly for generating ultrasonic waves according to one embodiment of the present invention may further include an elastic rod provided on the upper end of the piezoelectric vibrator to transmit vibration to the piezoelectric vibrator, and a power supply unit provided on one surface of the piezoelectric vibrator, so that a plurality of the horns and the elastic rods can be electrically connected in the form of a single plate.

The present invention has the effect of minimizing the manufacturing process by attaching multiple elastic rods and horns to a single flat piezoelectric vibrator so that the same ultrasonic signal can be generated simultaneously from multiple horns with a single electrical signal.

In addition, by adding a vibration plate frame that vibrates at a resonant frequency similar to that of the piezoelectric vibrator to both ends of the piezoelectric vibrator, it has the effect of improving the sound quality without vibration constraint.

In addition, the emitting part where the negative pressure is generated and the power supply part where the power is supplied are separated to enable waterproofing, and the piezoelectric vibrators are configured in multiple modular units so that they can be selectively separated for easy maintenance.

FIG. 1 is a perspective view showing the overall shape of a piezoelectric transducer assembly for generating ultrasonic waves according to a first embodiment of the present invention.
FIG. 2 is a drawing for explaining the fixing form of a vibration plate frame according to the first embodiment of the present invention.
FIG. 3 is a drawing for explaining the resonant frequency vibration displacement state depending on whether or not a vibration plate frame according to the first embodiment of the present invention is installed.
FIG. 4 is a drawing for explaining a resonant frequency vibration displacement state according to a change in the length of a vibration plate frame according to the first embodiment of the present invention.
FIG. 5 is a perspective view showing the overall shape of a piezoelectric transducer assembly for generating ultrasonic waves according to a second embodiment of the present invention.
FIG. 6 is a perspective view showing the overall shape of a piezoelectric transducer assembly for generating ultrasonic waves according to a third embodiment of the present invention.
FIG. 7 is a perspective view showing the overall shape of a piezoelectric transducer assembly for generating ultrasonic waves according to a third embodiment of the present invention with a power supply unit added.
FIG. 8 is a perspective view showing the overall shape of a piezoelectric transducer assembly for generating ultrasonic waves according to a third embodiment of the present invention with a fixed plate added.
FIG. 9 is a perspective view showing the overall shape of a piezoelectric transducer assembly for generating ultrasonic waves according to the fourth embodiment of the present invention.
FIG. 10 is a drawing for explaining the modular structure of a piezoelectric transducer assembly for generating ultrasonic waves according to a third embodiment of the present invention.

The specific details of the present invention, including the problems to be solved, the means for solving the problems, and the effects of the invention, are included in the embodiments and drawings described below. The advantages and features of the present invention, and the methods for achieving them, will become clearer with reference to the embodiments described below in detail together with the attached drawings.

Hereinafter, the present invention will be described in more detail with reference to the attached drawings.

FIG. 1 is a perspective view showing the overall shape of a piezoelectric transducer assembly for generating ultrasonic waves according to a first embodiment of the present invention.

FIG. 2 is a drawing for explaining the fixing form of a vibration plate frame according to the first embodiment of the present invention.

FIG. 3 is a drawing for explaining the resonant frequency vibration displacement state depending on whether or not a vibration plate frame according to the first embodiment of the present invention is installed.

FIG. 4 is a drawing for explaining a resonant frequency vibration displacement state according to a change in the length of a vibration plate frame according to the first embodiment of the present invention.

FIG. 5 is a perspective view showing the overall shape of a piezoelectric transducer assembly for generating ultrasonic waves according to a second embodiment of the present invention.

FIG. 6 is a perspective view showing the overall shape of a piezoelectric transducer assembly for generating ultrasonic waves according to a third embodiment of the present invention.

FIG. 7 is a perspective view showing the overall shape of a piezoelectric transducer assembly for generating ultrasonic waves according to a third embodiment of the present invention with a power supply unit added.

FIG. 8 is a perspective view showing the overall shape of a piezoelectric transducer assembly for generating ultrasonic waves according to a third embodiment of the present invention with a fixed plate added.

FIG. 9 is a perspective view showing the overall shape of a piezoelectric transducer assembly for generating ultrasonic waves according to the fourth embodiment of the present invention.

FIG. 10 is a drawing for explaining the modular structure of a piezoelectric transducer assembly for generating ultrasonic waves according to a third embodiment of the present invention.

Referring to FIG. 1, a piezoelectric transducer assembly (100) for generating ultrasonic waves according to an embodiment of the present invention may include a piezoelectric vibrator (110), an elastic rod (120), a horn (130), a vibrating plate frame (140), and a fixed plate (150).

The piezoelectric vibrator (110) can be configured as a bimorph type in which a vibrating plate formed in a flat shape and piezoelectric ceramics are attached to the upper and lower surfaces of the vibrating plate, respectively. The piezoelectric vibrator (110) can be designed in various shapes such as circular and polygonal.

The above piezoelectric vibrator (110) generates vibration when an electrical signal is applied.

The elastic bar (120) is formed in a bar shape, one end of which is connected to the piezoelectric vibrator (110), and the other end of which can be connected to the horn (130) described below.

That is, the elastic rod (120) receives the vibration of the piezoelectric vibrator (110) and amplifies the vibration of the piezoelectric vibrator (110) in the negative pressure direction. The elastic rod (120) may be composed of a metal or carbon rod, and its design can be changed in various ways.

In addition, the elastic rod (120) is a necessary component when the piezoelectric transducer assembly (100) for ultrasonic generation according to an exemplary embodiment is waterproof, and in a structure that does not require waterproofing, the elastic rod (120) may be omitted to reduce cost and improve performance.

The horn (130) may be provided at the end of the elastic rod (120). It receives vibrations of the piezoelectric vibrator (110) by an electric signal to generate ultrasonic waves and generate sound pressure. By sending sound along with ultrasonic waves, the sound has excellent straightness. The horn (130) through which sound is emitted may be exposed to the outside, and the shape of the horn (130) exposed to the outside may be configured in a cone shape to guide sound toward a target direction and prevent it from being dispersed in other directions. In addition, the horn (130) may be configured of a metal material.

A vibration plate frame (140) may be provided between the piezoelectric ceramics. The vibration plate frame (140) is formed in the shape of a long flat plate in the longitudinal direction, supports both ends of the piezoelectric vibrator (110), and serves to guide the piezoelectric vibrator (110) so that it can flexibly move up and down by ultrasonic vibration.

More specifically, the vibration plate frame (140) can vibrate at a resonant frequency similar to that of the piezoelectric vibrator (110) to minimize vibration interference of the piezoelectric vibrator (110).

The material of the above vibration plate frame (140) is a metal body and can be designed in various ways, and the shape of the above vibration plate frame (140) can be configured as any one of a T-shape, an I-shape, and an H-shape.

A fixed plate (150) may be provided on the upper end of the vibration plate frame (140). The fixed plate (150) may have a plurality of grooves formed at preset intervals in the longitudinal direction of the plate-shaped body. The piezoelectric vibrator (110) may be installed in the grooves. The fixed plate (150) serves to fix one side of the vibration plate frame (140) and, at the same time, to separate the emitting part where the sound pressure (ultrasonic wave) of the horn (130) is generated and the power supply part where power is applied.

More specifically, referring to (a) of Fig. 1, the vibration plate frame (140) according to the first embodiment may be configured in a T-shape.

It can be composed of a fixed area portion (141) that is fixedly supported by the fixed plate (150) and an elastic area portion (142) that is not fixed to the fixed plate (150) and is elastically supported by being connected to the piezoelectric vibrator (110).

And, referring to (b) of Fig. 1, the fixed area portion (141) and the elastic area portion (142) can be formed repeatedly at preset intervals along the longitudinal direction to form one frame. Referring to (c) of Fig. 1, a plurality of the vibration plate frames (140) can be arrayed into one assembly.

The fixing form of the vibration plate frame (140) according to the first embodiment is described as follows.

Fig. 2 (a) shows a state in which both ends of the piezoelectric vibrator (110) are fixed, and Fig. 2 (b) shows a state in which the elastic oscillator of the vibration plate frame (140) supports both ends of the piezoelectric vibrator (110) so that both ends of the piezoelectric vibrator (110) can move up and down. Fig. 2 (c) shows a graph of the experimental results of the sound output state. It was found that the sound output efficiency was higher in a state in which both ends of the piezoelectric vibrator (110) could move freely than in a state in which the piezoelectric vibrator (110) was fixed.

Referring to Fig. 3, when the piezoelectric vibrator (110) is in a free state, it vibrates and generates sound waves in the horn (130). However, when both ends of the piezoelectric vibrator (110) are fixed, the fixed portion does not vibrate, resulting in a decrease in sound output efficiency.

Therefore, by adding the vibration plate frame (140) to both ends of the piezoelectric vibrator (110), the piezoelectric vibrator (110) can be supported to freely vibrate in the same manner as when it is in a free state, thereby improving the sound output efficiency.

Referring to FIG. 4, the elastic region (142) may be configured to be less than or equal to the maximum length of the piezoelectric vibrator (110). The piezoelectric vibrator (110) and the elastic region (142) resonate due to ultrasonic vibration. However, if the elastic region (142) becomes longer than the length of the piezoelectric vibrator (110), the resonance mode is deviated, resulting in deterioration of acoustic characteristics. Therefore, it is preferable to be configured to be less than or equal to the maximum length of the piezoelectric vibrator (110).

For example, if the shape of the piezoelectric vibrator (110) is square, it is preferable that the length of the diagonal of the piezoelectric vibrator (110) be less than or equal to the length (maximum length), and if the shape of the piezoelectric vibrator (110) is circular, it is preferable that the length of the diagonal of the piezoelectric vibrator (110) be less than or equal to the diameter (maximum diameter) of the piezoelectric vibrator (110).

The overall shape of the piezoelectric transducer assembly (200) for generating ultrasonic waves according to the second embodiment of the present invention is described as follows.

More specifically, referring to (a) of FIG. 5, the vibration plate frame (140) according to the second embodiment may be configured in an I shape.

It can be composed of a fixed area portion (141) that is fixedly supported by the fixed plate (150) and an elastic area portion (142) that is not fixed to the fixed plate (150) and is elastically supported by being connected to the piezoelectric vibrator (110).

And, referring to (b) of Fig. 5, the fixed area portion (141) and the elastic area portion (142) can be repeatedly formed at preset intervals along the longitudinal direction to form one frame. Referring to (c) of Fig. 5, a plurality of the vibration plate frames (140) can be arrayed as one assembly.

The overall shape of the piezoelectric transducer assembly (300) for generating ultrasonic waves according to the third embodiment of the present invention is described as follows.

More specifically, referring to (a) of Fig. 6, the vibration plate frame (140) according to the third embodiment can be configured in an H shape.

It can be composed of a fixed area portion (141) that is fixedly supported by the fixed plate (150) and an elastic area portion (142) that is not fixed to the fixed plate (150) and is elastically supported by being connected to the piezoelectric vibrator (110).

And, referring to (b) of Fig. 6, the fixed area portion (141) and the elastic area portion (142) can be repeatedly formed at preset intervals along the longitudinal direction to form one frame. Referring to (c) of Fig. 6, a plurality of the vibration plate frames (140) can be arrayed as one assembly.

The overall shape of the piezoelectric transducer assembly for ultrasonic generation according to the third embodiment of the present invention with a power supply unit (160) added is described as follows.

Referring to Fig. 7, a power supply unit (160) may be further provided on one surface of the piezoelectric vibrator (110). The power supply unit (160) may be formed of a PCB board and is provided on the upper and lower surfaces of the piezoelectric vibrator (110), respectively, so that when electrically connected to the vibration plate frame (140), a plurality of the horn units (130) and the carbon rod can be connected as one.

The overall shape of the piezoelectric transducer assembly for ultrasonic generation according to the third embodiment of the present invention with a fixed plate (150) added is described as follows.

More specifically, as shown in (a) of Fig. 8, the fixed plate (150) may be provided on the upper end of the vibration plate frame (140). As shown in (c) of Fig. 8, the fixed area portion (141) fixed to the fixed plate (150) and the elastic area portion (142) not fixed to the fixed plate (150) may be provided. Accordingly, the elastic area portion (142) may freely vibrate in the up-and-down direction to transmit vibration to the piezoelectric vibrator (110), the elastic rod (120), and the horn portion (130).

Referring to FIG. 9, the overall shape of the piezoelectric transducer assembly (400) for generating ultrasonic waves according to the fourth embodiment of the present invention is described as follows.

The piezoelectric transducer assembly (100, 200, 300) for ultrasonic generation according to the first to third embodiments may be configured as a waterproof type in which the fixing plate (150) and the waterproof member are separately provided on the upper end of the vibration plate frame (140) to separate the emitting unit where the negative pressure (ultrasonic wave) of the horn (130) is generated and the power supply unit (160) where power is supplied.

On the other hand, the piezoelectric transducer assembly (400) for ultrasonic generation according to the fourth embodiment has the fixed plate (150) provided at the bottom of the vibration plate frame (140) and the horn (130) provided directly at the top, so that assembly is simpler and manufacturing costs can be lower than for a waterproof assembly.

Referring to Fig. 10, the piezoelectric vibrator (110) may be configured in a modular manner in which multiple units can be installed alternately.

When arranging the above piezoelectric vibrators (110), the greater the number, the greater the sound pressure (ultrasonic wave) output intensity. At this time, if one of the disk-shaped piezoelectric vibrators (110) in the prior art malfunctions, a problem occurs in which the entire piezoelectric vibrator (110) must be replaced.

Accordingly, a plurality of the above piezoelectric vibrators (110) are assembled to form one module (M), and one module (M) is grouped again to be selectively separable, thereby enabling maintenance.

More specifically, a plurality of piezoelectric vibrators (110) may be arranged in a row on the fixed plate (150) and the fixed plate (150) may be mounted inside the module (M) and fastened with bolts.

Multiple modules (M1, M2, M3??) can be grouped in various ways, such as by insertion or bolt connection.

As described above, although one embodiment of the present invention has been described by limited embodiments and drawings, one embodiment of the present invention is not limited to the described embodiments, and various modifications and variations are possible from this description by those with ordinary knowledge in the field to which the present invention pertains. Therefore, one embodiment of the present invention should be understood only by the scope of the patent claims described below, and all equivalent or equivalent modifications thereof will be considered to fall within the scope of the present invention.

100, 200, 300, 400: Piezoelectric transducer assembly for ultrasonic generation
110: Piezoelectric vibrator
120: Elastic bar
130: Mixed
140: Vibration plate frame 141: Fixed area
142: Elastic region
150: Fixed plate
160: Power supply
M: Module

Claims (5)

A flat piezoelectric vibrator with piezoelectric ceramics attached to the upper and lower surfaces;
A horn provided at one end of the above piezoelectric vibrator, which generates ultrasonic waves by vibration;
A vibration plate frame provided between the piezoelectric ceramics to support both ends of the piezoelectric vibrator and vibrate in a resonant mode while minimizing vibration displacement interference of the piezoelectric vibrator and transmitting an electrical signal;
A fixing plate provided on the upper part of the above vibration plate frame and fixing one side of the above vibration plate frame; including,
The above vibration plate frame is,
A fixed area formed as a single flat plate in the longitudinal direction and fixedly supported by the fixed plate; and
A piezoelectric transducer assembly for generating ultrasonic waves, characterized in that an elastic region portion that is elastically supported by contacting the piezoelectric vibrator is repeatedly formed at preset intervals. delete In the first paragraph,
The length of the above elastic region is,
A piezoelectric transducer assembly for generating ultrasonic waves, characterized in that it is configured to be less than the maximum length of the piezoelectric vibrator. In the first paragraph,
The shape of the above vibration plate frame is:
A piezoelectric transducer assembly for generating ultrasonic waves, characterized in that it is configured in one of a T-shape, an I-shape, and an H-shape. In the first paragraph,
An elastic rod is further provided on the upper end of the piezoelectric vibrator to transmit vibration to the piezoelectric vibrator.
A piezoelectric transducer assembly for generating ultrasonic waves, characterized in that a power supply unit is provided on one side of the piezoelectric vibrator, and a plurality of the horns and the elastic rods can be electrically connected as a single flat plate.