KR102085844B1 - Sound convertor - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an acoustic transducer, and more particularly, to an acoustic transducer capable of improving split vibration by providing a suspension connecting a lower end or a lower side of a voice coil to a frame.
The acoustic conversion device of the present invention includes a frame, a lower plate composed of an outer lower plate and an inner lower plate, an upper plate composed of an outer upper plate and an inner upper plate, a center magnet mounted between the inner upper plate and an inner lower plate, A first suspension consisting of first to fourth sub magnets spaced apart from the center magnet mounted between the outer upper plate and the outer lower plate by a predetermined gap (magnetic gap), a center dome and an edge dome mounted on the top of the frame, and an FPCB A second suspension attached to the bottom of the diaphragm 40, a lower end of which is located in a magnetic gap between the center magnet and the first to fourth sub magnets, and an upper end of which is a voice coil attached to the bottom of the second suspension; Through the respective spaces between the first and second sub-magnets and the third and fourth magnets The suspension consists of a 3 consisting of the first to fourth dampers connecting the lower frame and the coil device.

Description

Sound conversion device {SOUND CONVERTOR}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an acoustic transducer, and more particularly, to an acoustic transducer capable of improving split vibration by providing a suspension connecting a lower end or a lower side of a voice coil to a frame.

Conventional acoustic transducers (eg, microspeakers, etc.) do not use a wide band of sound sources due to communication technology limitations. However, with the development of information and communication technology, the playback bandwidth of the sound source to be reproduced in the sound conversion device has been widened and the required output has been increased, so the structure of the conventional sound conversion device has limitations in terms of characteristics and reliability.

In order to improve this point, the applicant of the present invention has been filed and registered in the Republic of Korea Patent No. 10-1200435 "high power micro speaker" (hereinafter referred to as "prior patent"), the high power micro speaker is a frame, protector, A yoke assembly coupled to the frame and provided with a magnet, a vibration plate provided in the frame to generate vibration, a voice coil coupled to the vibration plate to vibrate the vibration plate, and provided at one side of the frame and electrically connected between the lead wire and the external terminal of the voice coil. Terminals and center diaphragm, side diaphragm and voice coil to provide connection, side diaphragm are attached, outer diaphragm and voice coil contacting frame and protector, outer and inner parts are connected, and lead wire of coil is soldered Or out of the support and the outer part with a land to be welded It consists of a damper formed of an FPCB having an extension formed to provide a terminal provided in the frame and an electrical connection of the outer portion.

In the prior patent of the present applicant, the vibration system is composed of a damper and a voice coil formed of a diaphragm and an FPCB, and the distance between the diaphragm and the damper is close and relatively far from the lower end of the voice coil where the motion is generated by the actual magnetic force. There was a limit to improving split vibration.

In addition, the applicant's prior patent had a fear of deformation due to heat due to the inflow of the outside air into the diaphragm.

An object of the present invention is to provide a sound conversion device that can improve the split vibration by adding a suspension connecting the lower or lower side of the voice coil and the frame, and to lower the temperature of the diaphragm by smoothing the air flow inside. It is done.

The acoustic conversion device of the present invention includes a frame having a rectangular structure, a first suspension that is mounted on the upper side of the frame and vibrates, a second suspension that is attached to the bottom of the first suspension and electrically connected to the voice coil and vibrates, and a center magnet. And a plurality of sub magnets spaced apart from the center magnet at a predetermined interval to form a magnetic gap, a plurality of upper plates positioned above each of the center magnet and the plurality of sub magnets, and a lower portion of each of the center magnet and the plurality of sub magnets. It consists of a magnetic circuit consisting of a lower plate to be positioned, a voice coil attached to the bottom of the second suspension, and a third suspension vibrating by connecting a frame with a lower or lower side of the voice coil, each of the plurality of sub-magnets The third suspension is positioned through the spaced apart space, the third suspension A plurality of first attachment portions attached to the bottom surface of the seating portion formed at the edge of the frame, a second attachment portion attached to the bottom or bottom side of the voice coil, and a damper portion connecting the first attachment portion and the second attachment portion. The first suspension comprises a center dome located in the center, a first seating portion on which the outer periphery of the center dome is seated, and a second seating portion seated on the frame and between the first seating portion and the second seating portion. An edge dome composed of a dome, wherein the edge width of the damper portion is larger than the width of the straight portion of the dome of the edge dome.

The present invention has the effect of improving the divided vibration by constructing a vibration system in the first suspension and voice coil and show Scoring one third suspension attached to the bottom or lower side of the second suspension and voice coil attached to the top of the .

In addition, the present invention has a plurality of openings are formed in the corner portion of the outer upper plate to smooth the air flow inside the acoustic transducer, and in particular, to lower the internal heat during high power application, thereby suppressing deformation of the diaphragm and improving THD.

In addition, the present invention has the effect of improving the balance of vibration by supplementing the difference between the stiffness of the diaphragm of the long side and short side in the structure of the rectangular acoustic transducer.

1 is an exploded perspective view of an acoustic transducer according to the present invention.
2 is a perspective view of an acoustic transducer according to the present invention.
FIG. 3 is a cross-sectional perspective view taken along the line A-A 'of FIG. 2.
4A and 4B are vertical vibration amplitude graphs of the vibrometers of the prior art and the present invention.
5A and 5B are THD graphs of the prior art and the acoustic transducers of the present invention.
6A to 6C are graphs showing the relationship between the edge width A of the damper portion 71c and the width B of the straight portion of the long axis or short axis of the dome 44c .
7a and 7b are graphs showing the relationship between the damper unit edge width (A) of (71c) and a dome (44c) and the longitudinal straight portion shorter edges the width of the connecting portion between the straight portion (C) of.

In the following, the invention is explained in detail by way of examples and drawings.

1 is an exploded perspective view of an acoustic transducer according to the present invention, FIG. 2 is a perspective view of an acoustic transducer according to the present invention, and FIG. 3 is a sectional perspective view taken along the section line A-A 'of FIG.

The acoustic transducer includes a frame 10, a bottom plate mounted on the bottom of the frame 10 and composed of an outer bottom plate 22 and an inner bottom plate 23, an outer top plate 24 and an inner top plate 26. And a center magnet 32 mounted between the inner upper plate 26 and the inner lower plate 23, and mounted between the outer upper plate 24 and the outer lower plate 22. First to fourth sub-magnets 34a, 34b, 36a, and 36b spaced apart from each other (32) by a predetermined gap (magnetic gap), and a center dome 42 and an edge dome 44 mounted on the top of the frame 10. The first suspension 40 is configured to vibrate, for example, FPCB, etc., the second suspension 50 is attached to the bottom surface of the diaphragm 40 and vibrates, and the lower end is the center magnet 32 and the first Located in the magnetic gap between the fourth sub-magnets 34a, 34b, 36a, 36b. The upper end of each of the spaces between the voice coil 60 attached to the bottom of the second suspension 50 and the first and second sub magnets 34a and 34b and the third and fourth magnets 36a and 36b. It is composed of a third suspension that is composed of first to fourth dampers (70a to 70d) connecting the lower end of the voice coil 60 and the frame 10 through. The acoustic transducer of the present invention includes a voice coil 60, a first and second suspensions 40 and 50 attached to the upper end of the voice coil 60, and a vibration system composed of a third suspension. The acoustic conversion device of the present invention is a magnet (center magnet 32 and first to fourth sub- magnets 34a, 34b, 36a, 36b mounted between an upper plate, a lower plate, and an upper plate and a lower plate to form a magnetic gap ). It includes a magnetic circuit consisting of)).

In detail, the frame 10 has a hollow rectangular structure, and a combination of the first suspension 40 and the second suspension 50 is seated on an upper surface of the frame 10, and an outer upper plate 24 on upper surfaces of four corners. ) And the first to fourth seating portions 10a to 10d to which one end of the first to fourth dampers 70a to 70d are attached to the inner side or the inner bottom surface of the four corners . In addition, the frame 10 includes first and second terminals 12a and 12b for receiving an electric signal from a controller (not shown, for example, a microprocessor) of the electronic device.

The lower plate is integrally formed with the outer lower plate 22 and the inner lower plate 23 having grooves 22a interposed therebetween. The groove 22a prevents the voice coil 50 from colliding with the lower plate during vibration. First to second sub-magnets 34a and 34b are attached to the long axis of the outer lower plate 22, and third and fourth sub-magnets 36a and 36b are attached to the short axis of the outer lower plate 22.

The top plate consists of an outer top plate 24 and an inner top plate 26 at least spaced apart from each other by a magnetic gap. The outer top plate 24 includes first and second long shafts 24a and 24b with the first and second sub-magnets 34a and 34b attached to the bottom, and parallel to each other, and the third and fourth sub-magnets 36a. , 36b are attached to the bottom and parallel to each other, the first and second short axis portions 24c and 24d, and the first and second long axis portions 24a and 24b and the first and second short axis portions 24c and 24d. First to fourth connecting parts C1 to C4 are provided to connect each of them (that is, each corner of the outer upper plate 24), and the first to fourth connecting parts C1 to C4 are provided inside the first to fourth connecting parts C1 to C4. Fourth openings H1 to H4 are formed. The first to fourth openings H1 to H4 are provided to the voice coil 60 by smoothly flowing air between the first suspension 40, the second suspension 50, and the lower portion of the second suspension 50. Even when an electric signal for high power is applied, internal heat is reduced to suppress deformation of the diaphragm and improve THD. In addition, first and second grooves 26a and 26b are formed on the long axis side of the inner upper plate 26 to collide with the first and second protrusions 58a and 58b during the vibration of the second suspension 50. Prevent it.

The center magnet 32 is seated at the center of the outer upper plate 24 and the outer lower plate 23, and the first to fourth sub magnets 34a, 34b, 36a, and 36b are formed of the center magnet 32. From outside Magnetic gap is mounted spaced. In addition, the first sub- magnet 34a The third and fourth sub-magnets (36a, 36b) the first and the fourth connection portion, or the first and fourth intervals by corresponding to the (C1, C4) with respect to the The second sub magnet 34b is spaced apart from each other by the opening portions H1 and H4. For the third and fourth sub- magnets 36a and 36b by an interval corresponding to the second and third connecting portions C2 and C3 or the second and third They are spaced apart from each other by the openings H2 and H3 . In the present embodiment, the first to fourth sub-magnets 34a, 34b, 36a, and 36b are disposed corresponding to four sides of the center magnet 32, but the first to fourth sub-magnets 32 to 34 correspond to the long axis sides of the center magnet 32. It is also possible to arrange only the second sub-magnets 34a and 34b or to arrange only the third to fourth sub-magnets 36a and 36b in correspondence with the short axis of the center magnet 32.

The first suspension 40 has a center dome 42 located at the center, a first seat 44a on which the outer circumference of the center dome 42 is seated, and a second seat 44b on the frame 10. And an edge dome 44 composed of a dome 44c between the first seating portion 44a and the second seating portion 44b.

The second suspension 50 includes an inner circumferential portion 52 attached to the bottom of the first seating portion 44a, an outer circumferential portion 54 attached to the bottom of the second seating portion 44b, an inner circumferential portion 52, The first to fourth bridges 56a to 56d connecting the outer circumferential portion 54, the first and second protrusions 58a and 58b in the center direction on the long axis side of the inner circumferential portion 52, and the outer circumferential portion 54 and It consists of the 3rd and 4th protrusions 58c and 58d in the center direction between the inner peripheral part 52 and the long axis side of the outer peripheral part 54. As shown in FIG. The inner circumferential portion 52 includes conductive first and second conductive portions (not shown) that are electrically separated from each other, and the first conductive portion includes a first portion of the voice coil 60 through the conductive first protrusion 58a. The lead wire 62a is electrically connected to the lead wire, and the second conductive portion is electrically connected to the second lead wire 62b of the voice coil 60 through the conductive first protrusion 58a. The outer circumferential portion 54 includes third and fourth conductive portions (not shown) electrically separated from each other, and the third conductive portion is electrically connected to the first terminal 12a in electrical contact with the conductive third protrusion 58c. The fourth conductive portion is electrically connected to the second terminal 12b which is in electrical contact with the conductive fourth protrusion 58d. The first conductive portion and the third conductive portion are electrically connected through one of the conductive first and second bridges 56a and 56b, and the second conductive portion and the fourth conductive portion are conductive third and fourth bridges 56c. , 56d). Further, the first to fourth bridges 56a to 56d connect the short axis inner side of the outer circumferential portion 54 and the long axis outer side of the inner circumferential portion 52, or the long axis inner side of the outer circumferential portion 54 and the short axis outer side of the inner circumferential portion 52. The first to fourth bridges 56a to 56d are equally arranged in the long axis and the short axis direction even though a high output signal is applied to the voice coil 60 so that the inner circumferential portion 52 is twisted in the long axis and the short axis direction. Rotation is prevented so that the divided vibration is prevented at the time of vertical vibration of the voice coil 60.

The voice coil 60 may be wound around the voice coil bobbin, the upper end of the voice coil 60 is attached to the bottom of the inner circumferential portion 52 of the second suspension 50, and the lower end of the voice coil 60 is magnetic Located in the gap.

The third suspension includes a first attachment portion 71a attached to a bottom surface of each of the first to fourth mounting portions 10a to 10d, and a second attachment portion 71b attached to a lower end or a lower side of the voice coil 60. ) And first to fourth dampers 70a to 70d each configured of a damper portion 71c connecting the first attachment portion 71a and the second attachment portion 71b. The first to fourth dampers 70a to 70d are located in or below the space where the first to fourth openings H1 to H4 are formed. By connecting the lower end of the voice coil 60 and the frame 10 at the lower side of the first to fourth openings H1 to H4, the upper and lower vibration widths of the vibration system are equalized to improve the split vibration and to suppress the increase in harmonic components. To reduce harmonic distortion (THD).

In addition, although the shape of the damper part 71c has the dome structure which faces downward of the frame 10 in this embodiment, it extends substantially horizontally between the lower end of the voice coil 60 and the frame 10, It may have a wave shape, or may extend convexly downward of the frame between the lower end of the voice coil 60 and the frame 10 and may have a plurality of wave shapes.

4A and 4B are vertical vibration amplitude graphs of the vibrometers of the prior art and the present invention. The vertical vibration amplitude graph of the vibrometer according to the prior art of FIG. 4a shows an amplitude of up to about 0.35 mm according to the frequency of an electric signal applied during vertical vibration, and the vertical vibration amplitude graph of the vibration system of FIG. It exhibits an amplitude of up to about 0.29 mm depending on the frequency of the electrical signal applied at the time of vibration. In Figs. 4A and 4B, it is confirmed that by providing the third suspension, the vertical vibration amplitude of the vibration system can be equalized to suppress the divided vibration.

5A and 5B are THD graphs of the prior art and the acoustic transducers of the present invention. The THD graph of the vibration system according to the related art of FIG. 5A shows a maximum of about 60% of the THD in the low frequency band according to the frequency of the electric signal applied at the time of vertical vibration, and the THD graph of the vibration system according to the present invention of FIG. Depending on the frequency of the electrical signal applied at the time of vibration, the THD in the low band represents up to about 25%. 5A and 5B, it is confirmed that the increase of harmonic components is suppressed by the provision of the third suspension, thereby significantly reducing the THD.

In Fig. 3, the edge width A of the damper portion 71c constituted by the first to fourth dampers 70a to 70d, the width B of the long axis or short axis of the dome 44c, and the dome Between the edge width C of the connection portion between the long axis straight portion and the short axis straight portion of 44c affects the vibration control of the vibration system. It is preferable that at least one or more of the following equations (1) and (2) are satisfied for equal control of the vertical vibration amplitude of the vibration system.

First, with respect to Equation 1, FIGS. 6A to 6C are Of damper part 71c  Edge width A and the major or minor axis of the dome 44c. Straight  Graphs showing the relationship between the widths (B).

6A is the sound pressure level ( SPL : sound pressure level), where the red graph is A≥B and the blue graph is A <B. As shown in FIG. 6A, it is confirmed that the sound pressure level (unit dB) in the red graph when the equation 1 is satisfied is higher in most frequency bands than the blue graph.

6b is Harmonic distortion (THD)  The red graph is the case where A≥B and the blue graph is the case where A <B. As shown in FIG. 6B, in the red graph when the equation (1) is satisfied. Distortion rate in%  It is markedly lower than 1 kHz below the blue graph, and similar in higher frequency bands.

6C Vibrating part  Amplitude is shown, the blue graph is A≥B, and the black dotted line graph is A <B. As shown in FIG. 6C, the upper and lower sides of the amplitude in the blue graph where Equation 1 is satisfied are symmetrical, that is, the amplitude is uniform in the vertical direction, but the amplitude in the black dotted line graph is in the vertical direction. It is found that in some frequency bands it is nonuniform.

Above  From FIGS. 6A-6C, Of damper part 71c  Edge width A and the major or minor axis of the dome 44c. Straight  It is preferable that the width B satisfies the expression (1).

Next, the equation  For 2, Figures 7a and 7b Of damper part 71c  Corner width A and long axis of dome 44c With straight line  shorten Straight part  These graphs show the relationship between the edge widths C of the joints.

FIG. 7A is a graph when the edge width A is greater than the corner width C, and an upper vibration graph (blue) and a lower vibration are shown. The graph (red)  Unevenness Confirmed Split vibration Is generated .

FIG. 7B is a graph when the edge width A is less than or equal to the edge width C, and the upper vibration graph (blue) and the lower vibration are shown. The graph (red) Uniform Confirmed And split vibration is prevented.

As described above, the present invention is not limited to the above-described specific preferred embodiments, and any person having ordinary skill in the art without departing from the gist of the present invention claimed in the claims may have various It is to be understood that such changes may be made, and such changes will fall within the scope of the claims.

10: frame 22: outer lower plate
23: inner lower plate

Claims (6)

Square frame;
A first suspension seated on the upper side of the frame and vibrating;
A second suspension attached to the bottom of the first suspension and electrically connected to the voice coil and vibrating;
A center magnet, a plurality of sub-magnets spaced apart from the center magnet at a predetermined interval to form a magnetic gap, a plurality of top plates positioned above each of the center magnet and the plurality of sub-magnets, and each of the center magnet and the plurality of sub-magnets A magnetic circuit composed of a lower plate positioned at a lower portion thereof;
A voice coil attached to the bottom of the second suspension;
It consists of a third suspension that vibrates by connecting the frame with the bottom or bottom side of the voice coil,
The third suspension is positioned through a space formed by each of the plurality of sub-magnets spaced apart from each other,
The third suspension includes a first attachment portion attached to the bottom surface of the seating portion formed at the edge of the frame, a second attachment portion attached to the lower side or the bottom side of the voice coil, and a damper portion connecting the first attachment portion and the second attachment portion. Consisting of a plurality of dampers,
The first suspension is an edge dome consisting of a center dome located in the center, a first seating part on which the outer circumference of the center dome is seated, a second seating part seated on the frame, and a dome between the first seating part and the second seating part. Done,
The edge width of the damper portion is larger than the width of the straight portion of the dome of the edge dome acoustic conversion device. The method of claim 1,
The damper part has a dome structure facing downward of the frame, or extends horizontally between the voice coil and the frame and has a plurality of bends, or convexly extending downward of the frame between the voice coil and the frame and has a plurality of bends. Sound converter. The method of claim 1,
The plurality of upper plates are composed of an inner upper plate attached to an upper side of the center magnet, and an outer upper plate spaced at least a magnetic gap from the inner upper plate and to which a plurality of sub magnets are attached.
An acoustic conversion device, characterized in that the opening is formed inside the corner of the outer upper plate. The method of claim 3, wherein
And the third suspension is located in or below the space where the opening is formed. The method of claim 1,
The second suspension is composed of an inner circumferential portion attached to the bottom of the first seating portion, an outer circumference portion attached to the bottom of the second seating portion, and a plurality of bridges connecting the inner circumference and the outer circumferential portion, each of which has a short inner side and An acoustic converter, comprising: connecting the outer side of the major axis of the inner circumference. The method of claim 1,
The lower plate is integrally composed of an inner lower plate on which the center magnet is mounted and an outer lower plate on which the plurality of sub magnets are mounted, and a groove is formed between the outer lower plate and the inner lower plate.

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