KR101471084B1 - Neck wear type ultrasound speakers substitute for earphone - Google Patents

Abstract

The present invention relates to a neck wear type ultrasound speaker substitute for an earphone using an ultrasound directional speaker array. More particularly, the present invention relates to a neck wear type ultrasound speaker substitute for an earphone by non-linearly demodulating predictable sound signal of secondary wave due to interference between two ultrasounds when two ultrasounds having an adjacent frequency is generated in air. The neck wear type ultrasound speaker substitute for an earphone according to the present invention includes: a support part having a bending portion having a ″U″ shape so that a person wears by a neck and a speaker mounted in the support part to generate a sound. The bending portion includes an ultrasound signal processor and a charge power supply. The speaker includes two first sound generators disposed and hinged at both ends of the support part to change a radiation direction of the sound by folding a hinge and two second sound generators disposed between the bending portion and the support part to generate the sound in a fixed direction. A connection terminal for input audible signal is further provided at an end of the support part.

Description

[0001] The present invention relates to a neck wear type ultrasound speaker substitute for earphone,

[0001] The present invention relates to a necklace-type ultrasonic speaker for an earphone set using an ultrasonic directing speaker array, and more particularly, to an ultrasonic speaker for an earphone substitute, which, when oscillating two ultrasonic waves having an adjacent frequency in the air, To an earphone-replacing necklace-type ultrasonic speaker using non-linearly predictable demodulation.

Generally speaking, the voice of a speaker or a person has a directivity. However, ordinary loudspeakers are essentially non-directional because they output electrical signals by modulating them into mechanical signals (paper trembling). However, as the box-shaped sound reflector or the shielding structure is formed as the enclosure, the sound radiation angle is maintained at about 65 degrees, so that the listener is made to listen.

In the prior art document No. 10-0922183 (Oct. 9, 2009), there is disclosed Nexon having a sound-oriented book and a comfortable fit. This is a neckphone made up of a support having a curved part and a speaker for generating sound and a speaker cover having a plurality of sound source holes formed in the upper part of the speaker, And an auxiliary support which is hingedly coupled to the shoulder of the wearer at both ends of the support portion so as to be foldable, and a circular tube-shaped protrusion is formed on the outer side of the sound generating portion, and the sound outputted from the speaker is guided And a sound source switch capable of adjusting an opening / closing area of the sound source hole to adjust the intensity of the sound radiated through the sound source hole is provided on the speaker cover. Thus, the directivity of the sound output from the speaker Improved, more realistic stereo effects Can pinch, and is characterized in that the fit and excellent in appearance design, so that as well as the adhesion stably on the wearer's shoulders to be elegant. However, the above-mentioned Patent Document No. 10-0922183 has a limitation in that the surround sound among the audible signals has intensity or direction using a mechanical structure.

Separately, a directional speaker is one in which a voice signal is output only in a specific direction of the speaker. The directional speaker principle controls the amplitude and phase of the output voice signal to generate a voice signal only in a specific direction when outputting a voice signal using a plurality of speakers and causes the sound to be attenuated in a specific direction to form a shadow area A signal obtained by modulating a voice signal into an ultrasonic wave using the characteristic that the propagation characteristic of the ultrasonic wave in the air has a directivity in the 50 kHz band and another ultrasonic wave having a reverse phase of the carrier ultrasonic wave, The second principle is that only the signal is output in a specific region.

Korean Patent No. 10-1152224 (May 25, 2012) discloses a method and apparatus for controlling a directional sound source based on a listening space in the prior art using the above-described principle. More specifically, in order to form a voice signal output from a plurality of array type speakers only in a specific space, a phase-controlled signal is output through each speaker using a sound source vector, so that a sound source is formed only in a specific space So that a voice signal is output. Here, the phase control method obtains a sound source vector value that maximizes a difference value between the acoustic energy E of the listening space and the acoustic energy E 'of the non-listening space, and outputs the sound vector value to each speaker. That is, the present invention relates to a directional sound source control method and apparatus using the first principle described above. That is, the method includes selecting a number of sound sources and a position to be used for sound output after setting a listening space and a non-listening space, selecting a total acoustic energy of the acoustic signal input to the selected sound source, Of the acoustic energy of the acoustic signal input to the selected sound source while maximizing a difference between the acoustic energy of the listening space and the non-listening space using the calculated acoustic energy values, Calculating a sound source vector and controlling the sound pressure and phase of the selected sound source according to the optimal sound source vector.

However, the above method is a technique for minimizing the energy of the listening space and the non-listening space by the sound source vector. If the listening space is extremely limited, the technique is limited. That is, when limiting the listening space to the listener's ear area, it does not provide a clear solution in defining the extended area in that area.

Korean Patent No. 10-0622078 (2006.09.01) of the prior art document to which the second principle is applied discloses a super directional speaker system and a signal processing method. The supergain speaker system modulates X (t) by adding the x '(t) signal generated by the signal compensation filter to the audio input signal x (t) through dynamic VBS modulation and then converts it into an ultrasonic amplifier and an ultrasonic transducer To the air. And then output as an audio signal through nonlinear demodulation in air. At this time, the characteristics of the ultrasonic transducer are modeled after the dynamic VSB modulation, and a pre-inverse filter is applied to the ultrasonic wave to be transmitted to the ultrasonic amplifier.

The prior art does not consider the structure of a speaker for miniaturization because the radiation angle is about 20 to 35 degrees even though it is an ultrasonic wave.

Korean Patent No. 10-0922183 (2009.10.09) Korean Registered Patent No. 10-115224 (May 25, 2012) Korean Patent No. 10-0622078 (2006.09.01)

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a necklace-type ultrasonic speaker for generating a voice signal using a speaker array having a minimized number of MEMS structures.

In addition, the present invention provides a necklace-type ultrasonic speaker for an earphone, which further includes a charging unit for controlling driving of the MEMS speaker array, and replaces an earphone which is difficult to ear when worn for a long time.

In order to attain the above object, the present invention provides a necklace-type ultrasonic speaker for an earphone, comprising: a supporting part having a U-shaped curved part to be worn on a person's neck; and a speaker built in the supporting part to generate sound, Wherein the first sound generating device is hinged to both ends of the support part, and the second sound generating device is hinged to both ends of the support part, And two ultrasonic loudspeakers whose acoustic radiation directions are changed according to the folding of the hinge. The second sound generator is composed of two ultrasonic loudspeakers positioned between the curved part and the supporting part and generating sound in a fixed direction, And a connection terminal for input / audible signals at one end of the support part. Ear substitute necklace-type ultrasonic speaker according to the.

Further, the necklace-type ultrasonic speaker for earphone according to the present invention is composed of a MEMS (microelectromechanical system) type speaker and the distance between the speakers is determined according to the size of the carrier wave to further enhance the linearity of the ultrasonic wave.

In addition, a necklace type ultrasonic speaker for an earphone according to the present invention implements a signal processing unit through an ultrasonic driving chip for driving an ultrasonic wave. In the ultrasonic driving chip, the ultrasonic wave is nonlinearly demodulated in air by an external audible signal A preprocessor for preliminarily processing the audible signal and a carrier wave generator for generating a carrier wave for transmitting a signal inputted from the preprocessor, a modulator for modulating a signal input from the preprocessor to the carrier wave, And amplifies the signal of the modulating part and sends the amplified signal to the ultrasonic speaker. And a charging power source unit for the ultrasonic signal processing unit.

In addition, the necklace-type ultrasonic speaker for earphone according to the present invention further includes an additional switch for controlling the driving (on / off) of the first sound generating device and the second sound generating device.

According to the neckband type ultrasonic speaker for earphone according to the present invention, since the listening interval is formed near the ear, it is possible to prevent the voice signal from being radiated to the surroundings and causing harm to other persons.

Further, according to the present invention, by arranging the array speaker group according to the wavelength of the carrier ultrasonic wave, it is possible to secure a stronger directivity and to reduce the area where the voice signal is output.

1 is a perspective view showing a necklace type ultrasonic speaker for an earphone according to the present invention.
FIG. 2 is a view showing a configuration of an ultrasonic driving chip incorporated in a necklace-type ultrasonic speaker for an earphone according to the present invention.
Fig. 3 is a view showing a mounting position and a structure of a MEMS-type speaker constituting the sound generating device according to the present invention.
4 is a view showing an acoustic radiation angle according to the present invention.

The present invention relates to a speaker having a U-shaped curved portion for wearing on a person's neck, and a speaker incorporated in the supporting portion to generate sound, wherein the curved portion is in close contact with a lower end of a rear thigh and an ultrasonic signal processing portion and a charging power source portion Wherein the first sound generating device and the second sound generating device are hinged to both ends of the supporting part so that the direction of sound radiation is changed according to the folding of the hinge, And the second sound generator is composed of two ultrasonic speakers positioned between the curved portion and the supporting portion to generate sound in a fixed direction and further includes a connection terminal for input and output signals at one end of the support portion And a neckband type ultrasonic speaker for an earphone.

The first sound generating device and the second sound generating device may be MEMS (micro electromechanical system) type speakers of an array structure, and the first sound generating device may be a combination of four MEMS type speakers. Wherein a distance d between the center points of the MEMS type loudspeakers is maintained at a distance equal to the wavelength lambda, the wavelength lambda having a value equal to a value obtained by dividing the propagation speed of the ultrasonic wave in air by the frequency of the carrier wave, And the center point of the four-speaker type speaker is connected by a line.

In addition, the present invention uses an ultrasonic driving chip for ultrasonic signal processing, and further includes a charging power unit for an ultrasonic driving chip. The ultrasonic driving chip controls the non-linear demodulation of an audible signal inputted from the outside, A preprocessor for pre-processing the audible signal; a carrier generator for generating a carrier wave for transmitting a signal input from the preprocessor; a modulator for modulating a signal input from the preprocessor to the carrier wave; Amplifies the negative signal and sends the amplified negative signal to the ultrasonic speaker.

The present invention further includes an additional drive selection switch for controlling the drive (on / off) selection of the first sound generator and the second sound generator.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the structure and overall operation of a necklace-type ultrasonic speaker for an earphone according to the present invention will be described in detail with reference to the accompanying drawings.

It is to be understood that the words or words used in the present specification and claims are not to be construed in a conventional or dictionary sense and that the inventor can properly define the concept of a term in order to describe its invention in the best possible way And should be construed in light of the meanings and concepts consistent with the technical idea of the present invention. Therefore, it should be understood that the embodiments described herein and the configurations shown in the drawings are only the most preferred embodiments of the present invention, and that various equivalents and modifications may be made thereto at the time of the present application shall.

FIG. 1 is a perspective view showing a necklace type ultrasonic speaker for an earphone according to the present invention, and FIG. 2 is a view showing a configuration of an ultrasonic driving chip incorporated in a necklace type ultrasonic speaker for an earphone according to the present invention. 3 is a view showing a mounting position and structure of a MEMS type speaker constituting the sound generating device according to the present invention, and FIG. 4 is a view showing an acoustic radiation angle according to the present invention.

As shown in FIG. 1, the earphone-type ultrasonic loudspeaker according to the present invention includes a supporter including a curved portion, an ultrasonic signal processor incorporated in the curved portion, a first sound generator and a second sound generator, And a connection terminal for receiving the data.

The support portion 20 including the curved portion 10 has a U-shaped shape for wearing on a person's neck. A charging power source unit and an ultrasonic signal processing unit 11 are incorporated in the curved portion. The curved portion 10 has a structure in which the width of the curved portion 10 is relatively larger than that of the supporting portion, since the charging power source portion and the ultrasonic signal processing portion 11 must be incorporated. It is configured so that it can be worn more comfortably when worn on a person's neck.

The functions and functions of the ultrasonic driving chip constituting the ultrasonic signal processing unit 11 shown in FIG. 2 will be described in more detail as follows.

In general, a directional speaker using an ultrasonic wave utilizes the fact that a voice signal due to the secondary wave due to interference is demodulated nonlinearly predictively when two sound waves (primary waves) having adjacent frequencies are incident on the medium.

The formula representing the sound pressure signal of this secondary wave is shown in Equation 1 below.

는 소리의 전파 속도이고,

는 매질(공기)의 밀도이며, z 는 초음파가 진행하는 축거리를 나타내고 A는 음원의 면적이다.

은 일차파동의 음압이고

는 공기의 비선형계수이다. Here, the above equation expresses the sound pressure when the waves having frequencies adjacent to each other interfere with each other to generate a secondary wave. Here, the function E is a function expressing the envelope of the original sound,

Is the propagation speed of sound,

Is the density of the medium (air), z is the axial distance traveled by the ultrasonic waves, and A is the area of the sound source.

Is the sound pressure of the primary wave

Is the nonlinear coefficient of air.

에 적용하는 것을 사전에 전처리하는 전처리부(13)에서 진행하게 된다. 이러한 전처리부(13)에서 출력되는 신호는 반송파(초음파)와 합성을 위하여 변조부(14)로 보내어지고, 초음파로 변조된 신호는 초음파 증폭기(15)를 거쳐 초음파 스피커(100, 200)로 출력되어 공기중으로 방사된다. 수학식1에 따라 공기 중에 방사된 초음파는 공기중에서 비선형 복조과정을 거쳐 출력되는 것을 이용하는 초음파 구동칩이다.
That is, in the ultrasonic driving chip of the ultrasonic signal processing unit 11 according to the present invention, the sound pressure of the secondary wave is proportional to the area of the sound source and the sound pressure output from the primary wave, and proportional to the secondary differential of E (envelope and envelope) The dynamic VSB method of AM modulation and the characteristics of the speaker are modeled and the inverse transform function

Processing unit 13 to pre-process the application to the pre-processing unit 13. The signal output from the preprocessor 13 is sent to the modulator 14 for synthesis with a carrier wave (ultrasonic wave), and the signal modulated by the ultrasonic wave is output to the ultrasonic speakers 100 and 200 through the ultrasonic amplifier 15 And is radiated into the air. The ultrasonic wave radiated into the air according to Equation (1) is output through a nonlinear demodulation process in the air.

The first sound generating device 100 and the second sound generating device 200 according to the present invention shown in FIG. 3 are composed of a MEMS (micro electro mechanical system) type ultrasonic speaker.

Generally, in order to obtain the directivity of a specific frequency band, the interval (d) of the MEMS type ultrasonic speaker must satisfy the following equation (2).

(Where d is the distance between the center points of the ultrasonic loudspeakers, c is the ultrasonic propagation velocity in the air, and f is the frequency of the ultrasonic waves).

To explain the principle according to this, the wavelength λ is the same as the distance d between the loudspeakers, and the ultrasonic signals in the direction to be radiated are synthesized with each other, so that the size of the signal becomes larger. Therefore, the ultrasonic loudspeakers 101, 102, 103, and 104 according to the present invention are designed to have the respective distances corresponding to the modulation frequency according to the modulation frequency, thereby maximizing the distance from the center of the ultrasonic propagation direction according to the distance.

4, the ultrasonic speaker structure according to the present invention is described in connection with the acoustic radiation angle 110 (&thetas;).

In the present invention, the ultrasonic speakers 101, 102, 103, and 104 use the theory that sound is interfered with and attenuated in a region where frequency of a frequency signal propagated in air or air is 1/2 of a wavelength, that is, .

It can be seen from the figure that signals at the point away from the center line 105 are interfered with and attenuated while the signals of the same phase are continuously superimposed and strengthened at the center line 105.

For example, if the carrier waves are fixed at 50 kHz in order to utilize the characteristic of being radiated well in the air at 50 kHz, the center-to-center distance of the MEMS type ultrasonic speaker can be estimated as 340 ÷ 50,000 = 0.68 cm. Here, the propagation velocity of the ultrasonic waves in the air is calculated by estimating the propagation velocity of the sound, though it is influenced by the air density.

Therefore, maintaining the interval of about 0.68 cm is a principle that further strengthens the linearity of the ultrasonic waves. Accordingly, when the pre-frequency of the ultrasonic wave as a carrier wave is determined, the interval between the midpoints of the MEMS type ultrasonic speakers 101, 102, 103, and 104 is determined according to Equation (2) By designing an ultrasonic speaker, you can create a higher directional speaker. Accordingly, the arrangement of the ultrasonic loudspeaker has a property of reinforcing the linearity of the ultrasonic waves radiated from the four ultrasonic speakers 101, 102, 103, and 104.

In addition, the MEMS type ultrasonic speaker has a structure in which a finer speaker is formed with an array structure, thereby enhancing the amplitude of the ultrasonic waves, thereby completing the disadvantage of the MEMS type ultrasonic speaker having a weak sound pressure.

In addition, the structure of the ultrasonic speaker according to the present invention in addition to the structure of the ultrasonic speaker of the MEMS type secures a stronger directivity to the signal of the ultrasonic wave to be radiated with a rhombus shape. Due to this structure, It becomes possible to reinforce the speaker again.

1 to 4, a necklace type ultrasonic speaker for an earphone according to the present invention is worn on a person's neck, so that there is a case in which the voice signal can not be heard due to movement of a person.

In order to cope with this, the present invention comprises an acoustic-wave generating device composed of the first acoustic-generating device 100 and the second acoustic-generating device 200, and the first acoustic- And a drive selection switch (330) for selectively driving the apparatus and the second sound generator. That is, when the drive selection switch 330 is raised to the uppermost end, the second acoustic device 200 existing between the curved portion 10 and the support portion 20 is driven. When the first acoustic device 100 And the second sound generator 200 are simultaneously driven. When the drive selection switch is positioned at the lower end, only the first sound generator 100 is driven.

In addition, the first sound generator 100 is connected through a hinge to adjust an acoustic radiation direction according to a human body structure, and the hinge is adjusted so that a listener selects an audio signal in an optimal state .

As described above, according to the present invention, a necklace-type ultrasonic speaker for an earphone is formed only in the vicinity of the ear so that a voice signal is formed only in the vicinity of the ear, unlike the existing neck phone type, It will be possible.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, Modification is possible. Accordingly, it is intended that the scope of the invention be defined by the claims appended hereto, and that all equivalent or equivalent variations thereof fall within the scope of the present invention.

10. Bend 20. Support
11. Ultrasonic signal processing unit 12. Carrier wave generating unit
13. Pre-processing section 14. Modulation section
15. Ultrasonic wave amplifier 100. First sound generator
110. Radiation angle (?) 101,102,103,104 Ultrasonic speaker
105. Center line 200. Second sound generator
300. Micro USB charging terminal 310. Hinge
320. Connection terminal 330. Drive select switch

Claims (6)

1. A speaker for generating sound by being embedded in a support portion having a curved portion forming a " U " shape to be worn on a person's neck,
Wherein the curved portion is in close contact with the lower end of the rear neck, and an ultrasonic signal processing unit and a charging power source unit are built in,
The speaker is composed of a first sound generating device and a second sound generating device, and the first sound generating device is composed of two ultrasonic speakers hinged to both ends of the supporting part and changing the sound radiation direction according to the folding of the hinge And the second sound generator is composed of two ultrasonic loudspeakers positioned between the curved portion and the supporting portion and generating sound in a fixed direction,
And a connection terminal for an input audible signal at one end of the support part. The method according to claim 1,
The first sound generating device and the second sound generating device are constituted by an MEMS (microelectromechanical system) type speaker of an array structure, and one acoustic generating device is constituted by four combinations of the MEMS type speakers, The distance d between the center points of the loudspeaker

(Where f is the frequency of the carrier and c is the propagation velocity of the ultrasonic wave in air).
, And is set to be a rhombic pattern when it is assumed that the center points of the four lug type speakers constituting one sound generating device are connected by a line. The method according to claim 1,
Wherein the ultrasonic signal processing unit includes an ultrasonic driving chip,
The ultrasonic driving chip includes a preprocessor for predicting nonlinear demodulation of an audible signal input from the outside in the air and signal processing of the audible signal in advance
A carrier generator for generating a carrier wave for transmitting a signal input from the preprocessor;
A modulator for modulating a signal input from the preprocessor to the carrier wave;
And amplifies the signal of the modulating unit and sends the amplified signal to the ultrasonic speaker. The method according to claim 1,
Wherein the charging power source unit further comprises a micro USB charging terminal on a side of a support for charging the earphone. The method according to claim 1,
Wherein the earphone-mounted necklace-type ultrasonic loudspeaker further comprises an additional drive selection switch for controlling driving (on / off) selection of the first sound generator and the second sound generator. Ultrasonic speaker. The method according to claim 1,
Wherein the connection terminal further comprises a volume control terminal for adjusting an intensity of an input audible signal.

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