WO2010044623A2 - Diaphragm for sound converter and sound converter including the same - Google Patents

Abstract

The present invention discloses a diaphragm for a sound converter including a first diaphragm having a central portion which is a plane surface and a side dome formed around the central portion, and a second diaphragm formed at the central portion of the first diaphragm. The sound converter maximizes the volume of a magnet mounted therein, and thus improves a sound pressure of low frequency bands. In addition, the sound converter allows a lead wire of a coil portion to be pulled out without interfering with other elements, and thus stably transmits electrical signals without damaging the lead wire or the other elements.

Description

Diaphragm for sound conversion device and sound conversion device including the same

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a diaphragm for an acoustic transducer and an acoustic transducer including the same, and to a diaphragm and an acoustic transducer for increasing the effective area of the diaphragm of the acoustic transducer and lowering the rigidity of the diaphragm.

In general, a speaker converts electrical energy into mechanical energy by a voice coil existing between pores by Fleming's left-hand law that a conductor in which current flows in a magnetic field receives a force. That is, when a current signal containing several frequencies is applied to the voice coil, the voice coil generates mechanical energy according to the strength of the current and the magnitude of the frequency, and generates vibration on the diaphragm attached to the voice coil, thereby ultimately recognizing the human ear. It can generate a sound pressure of a predetermined magnitude.

The magnetic circuits of these speakers are designed so that the magnetic flux can be bridged at right angles to the voice coils present in the air gap by using a magnet (permanent magnet) and a top plate (or upper plate) in the yoke made of ferrous metal, respectively. The work is bonded to the diaphragm to generate the up and down excitation force by the input signal to vibrate the diaphragm bound to the frame to generate sound pressure. The diaphragm has various shapes of waves in order to remove the buckling phenomenon and excellent response during the up and down oscillation, and the shape of the diaphragm acts as a design variable having the greatest influence on the frequency characteristics.

1 is a cross-sectional view of a microspeaker according to the prior art.

As shown in FIG. 1, the microspeaker transmits the magnetic flux to or from the frame 1, the yoke 2 inserted and mounted inside the frame 1, and the yoke 2. The inner ring top plate 5 for receiving the magnetic flux from the inner ring magnet 3 and the outer ring magnet 4 and the inner ring magnet 3 or the outer ring magnet 4 so that the magnetic flux is transmitted at right angles to the voice coil 7 and A voice coil 7 and a voice coil in which a portion is inserted into the space between the outer ring top plate 6, the inner ring magnet 3 and the inner ring top plate 5, and the outer ring magnet 4 and the outer ring top plate 6 7) is attached to the diaphragm 8 to generate a vibration according to the vertical movement of the voice coil 7, the ventilation hole 9 provided in the frame 1 of the lower side of the diaphragm 8, and the sound emitting hole 11 ) Is formed, but the protector 10 to protect the diaphragm 8, and the leader line (not shown) of the voice coil 7 is the side of the frame (1) Through the grooves (not shown) formed in the through or to the frame (1) is drawn out are respectively soldered to the connection terminals 12 along the outer side of the frame (1). The connection terminal 12 allows a pair of lead wires (not shown) and lead wires (input lines and output lines) to be connected to each other from the outside.

The diaphragm 8 consists of a dome-shaped center dome 8a at the center, and a side dome 8b formed around the center dome 8a.

In the case of a general microspeaker, the acoustic characteristics are greatly affected by the size of the back volume of a device (for example, a mobile communication terminal) on which the microspeaker is mounted. According to the Helmholtz resonance equation, the back volume has a great influence on the equivalent stiffness of air. The smaller the back volume, the higher the equivalent stiffness, which lowers the sound pressure in the low range and increases the first resonance frequency.

In a magnetic circuit as in the prior art, within the limited frame size, it is difficult to increase the size of the entire magnets 3 and 4, making it difficult to increase the electromagnetic force. In addition, in the diaphragm according to the prior art, the side dome is relatively wide, and the effective area of the diaphragm is reduced, so that the sound pressure is lowered, and the diaphragm is formed from a single film having a relatively high rigidity, thereby deteriorating low frequency vibration characteristics. Moreover, when the back volume is small, this low frequency vibration characteristic is further deteriorated.

Also, in the conventional microspeaker, in order to avoid interference with the yoke or the like, when a leader line drawn out from the voice coil is drawn out, a method of bonding to the bottom of the diaphragm by bonding or the like is used. The joining process of the lead coil and the diaphragm of the voice coil is performed by a bonding process in which the lead wire is fixed by bonding the lead to the bottom of the diaphragm, and is made by hand even though high precision is required, and the process time is long. The cost increases. In addition, the defect is frequently caused by the most vulnerable part of the microspeaker manufacturing process.

In addition, since the lead wire is fixed to the vibration plate by the bond, when the electrical signal is converted into the acoustic signal through the vibration, the vibration of the diaphragm due to the unbalanced mass and the strong component of the gun, so that the vibration characteristics deteriorate acoustic characteristics There is this.

An object of the present invention is to provide a sound conversion device to maximize the volume of the magnet mounted to the sound conversion device.

In addition, an object of the present invention is to provide an acoustic conversion device having a diaphragm for optimizing the width of the side dome and increasing the effective area of the diaphragm.

Moreover, an object of this invention is to provide the acoustic conversion apparatus which makes it easy to laminate | stack a diaphragm which consists of multiple layers.

In addition, an object of the present invention is to provide an acoustic conversion apparatus that allows the lead line of the coil unit to be drawn out without interference with other elements.

In addition, an object of the present invention is to provide a sound conversion device that extends the leader line to minimize the effect of the leader line of the coil portion on the diaphragm.

It is also an object of the present invention to provide an acoustic transducer which increases the reliability of the coupling between the yoke assembly and the frame.

The present invention provides a diaphragm for an acoustic transducer comprising a first vibrating plate formed of a central portion which is planar, and a side dome formed around the central portion, and a second vibrating plate formed at the central portion of the first vibrating plate.

In another aspect, the present invention, the central portion of the first vibration plate is composed of an opening in the center and a central seating end to which the second vibration plate is mounted around the opening, and the central seating end is connected to the side dome. To provide.

The present invention also provides a diaphragm for an acoustic transducer, wherein a step for guiding the second vibrating plate is formed inside the side dome of the first vibrating plate.

The present invention also provides a diaphragm for an acoustic transducer, wherein the side dome of the first vibration plate and the second vibration plate are spaced apart from each other by a predetermined interval.

In addition, the present invention, the first vibration plate is a first sub-vibration plate containing a thermoplastic polyurethane elastomer (TPU) and polyester (PET) material,Polyetherimide (PEI) Material, Polyether Ether Ketone It provides a diaphragm for an acoustic transducer, comprising a laminate of a second sub-vibration plate including at least one of a (PEEK) material and a polyarylate material.

The present invention also provides a diaphragm for an acoustic transducer, wherein the first sub diaphragm and the second sub diaphragm are sequentially positioned and laminated.

In another aspect, the present invention provides a vibration plate for an acoustic transducer, characterized in that the second vibration plate is composed of first and second metal layers and an elastic layer laminated between the first and second metal layers.

The present invention also provides a diaphragm for an acoustic transducer, wherein the first and second metal layers are aluminum layers.

The present invention also provides a diaphragm for an acoustic transducer, wherein the elastic layer is a styrofoam (PS material) layer.

The present invention also provides a diaphragm for an acoustic transducer, wherein the width of the side dome corresponds to 10 to 20% of the radius of the diaphragm or 20 to 30% of the radius of the diaphragm short axis.

The present invention also provides a diaphragm for an acoustic transducer, wherein the thickness of the second vibrating plate is 0.25 to 0.35 mm.

The present invention also provides a diaphragm according to any one of claims 1 to 11, a coil portion mounted around the bottom surface of the central portion of the diaphragm, a magnetic circuit for causing the magnetic flux to be bridged at right angles to at least a portion of the coil portion, and a magnetic circuit on the lower side. It provides a sound conversion device comprising a protector for protecting the diaphragm on the frame and the frame having a first receiving portion for accommodating, and the second receiving portion for receiving the diaphragm on the upper side.

In another aspect, the present invention provides a sound conversion device, characterized in that the coil portion attached to the rear surface of the diaphragm is mounted so as to overlap a predetermined width or more on the second vibrating plate with the first vibrating plate interposed therebetween.

In addition, the present invention provides a sound conversion apparatus, characterized in that the overlapping degree is 50% or more.

In another aspect, the present invention provides a sound converting apparatus, characterized in that the protector has a sound emitting hole having a size equal to or wider than that of the central portion or the second vibration plate of the diaphragm.

In another aspect, the present invention provides an acoustic conversion device characterized in that the drawing groove is formed in one end of the frame, the lead wire of the coil portion is bent at least one or more times below the side dome to advance to the drawing groove.

In addition, the present invention is a diaphragm assembly consisting of a diaphragm consisting of a central portion of the plate, a side dome having a thickness thinner than the thickness of the central portion, and a coil portion mounted around the bottom of the central portion, perpendicular to at least a portion of the coil portion. A frame having a magnetic circuit allowing the magnetic flux to bridge, a first accommodating portion accommodating the magnetic circuit at the lower side, and a second accommodating portion accommodating the diaphragm assembly so that the coil portion is disposed between the spaced space at the upper side, and the diaphragm assembly at the upper side of the frame. It provides a sound conversion device comprising a protector to protect the.

In another aspect, the present invention provides a sound conversion device comprising a first vibration plate having a central portion and a side dome, and a second vibration plate mounted on an upper surface of the central portion of the first vibration plate.

In addition, the present invention is that the diaphragm is composed of a third vibration plate made of a side dome having an opening is formed in the center, the center seat end around the opening, and a fourth vibration plate mounted on the upper surface of the center seat end to form a center part. It provides a sound conversion device characterized by.

In another aspect, the present invention provides an acoustic conversion device characterized in that the drawing groove is formed in one end of the frame, the lead wire of the coil portion is bent at least one or more times below the side dome to advance to the drawing groove.

In another aspect, the present invention provides a sound conversion device, characterized in that the lead wire path for advancing the lead wires of the coil portion to the lead groove, the lead wire path for preventing contact with the magnetic circuit is formed.

In another aspect, the present invention, the magnetic circuit includes a yoke consisting of a magnet, a top plate mounted on the magnet and a side plate mounted to form a space between the base on which the magnet is mounted and the sides of the magnet around the base. The leader line includes a first groove formed above the side plate of the yoke, and the leader line travels through the inside of the first groove or travels above the first groove.

In addition, the present invention provides a sound conversion apparatus, characterized in that the leader line path is formed adjacent to the first receiving portion of the frame, and has a second groove leading the leader line to the leader groove.

In another aspect, the present invention provides a sound conversion device, characterized in that the second groove is formed in the partition wall separating the first accommodation portion and the second accommodation portion.

In another aspect, the present invention provides a sound conversion device characterized in that the drawing groove is formed stepped with respect to the diaphragm seating portion formed in the frame.

In another aspect, the present invention provides a sound conversion device, characterized in that the first groove and the second groove are formed to face each other.

In another aspect, the present invention provides a sound conversion apparatus, characterized in that the first groove is a pair of grooves separated from each other by the support plate, the second groove has an inner groove for receiving the support plate.

In another aspect, the present invention provides a sound converting apparatus, characterized in that the second groove has an inner projection inserted into the first groove.

The present invention has the effect of maximizing the volume of the magnet mounted on the sound conversion device, thereby inducing sound pressure improvement in the low frequency band.

In addition, the present invention has the effect of improving the low-frequency vibration characteristics, widening the effective area of the diaphragm to improve the sound pressure.

In addition, the present invention is to facilitate the lamination of the diaphragm consisting of a plurality of layers, there is an effect to make the production easy and accurate.

In addition, the present invention has the effect that the lead line of the coil unit is drawn out without interference with other elements, so that the lead line is damaged or other elements are not damaged and the transmission of the electrical signal is made safe.

In addition, the present invention has the effect of minimizing the influence on the sound pressure of the diaphragm by extending the lead-out line to minimize the effect of the lead line of the coil portion on the diaphragm.

In addition, the present invention has the effect of strengthening the coupling between the yoke assembly and the frame, thereby increasing the strength reliability of the acoustic transducer.

1 is a cross-sectional view of a microspeaker according to the prior art.

2 is a cross-sectional view of an acoustic transducer to which the diaphragm according to the present invention is applied.

3 is a perspective view of the yoke assembly of FIG. 2.

4 and 5 are a perspective view and a plan view of the frame of FIG.

6 and 7 are views illustrating a manufacturing process of the diaphragm.

8 is another embodiment of the diaphragm of FIG. 2.

9 to 14 are embodiments of the diaphragm and its performance graph.

15 to 19 illustrate embodiments of the positional relationship between the first vibration plate, the second vibration plate, and the coil unit.

20 is a detailed plan view of the diaphragm.

21 is a partially enlarged view of the protector and the diaphragm of FIG. 2.

22 and 23 are partially enlarged views of the coil unit.

24 is a bottom perspective view illustrating the positional relationship between the diaphragm and the coil unit.

25 is a perspective view of another embodiment of the yoke assembly of FIG. 2.

26 and 27 are a perspective view and a plan view of another embodiment of the frame of FIG.

28 and 28 are partially enlarged views of another embodiment of the coil unit.

30 is a bottom perspective view illustrating a positional relationship of another embodiment of the diaphragm and the coil unit.

31 is a graph of comparison of sound pressure (SPL) between the prior art and the present invention.

32 is a graph of sound distortion (THD) comparison between the prior art and the present invention.

In the following, the invention is explained in detail based on the embodiments of the invention and the accompanying drawings.

2 is a cross-sectional view of the applied acoustic transducer of the diaphragm according to the present invention, FIG. 3 is a perspective view of the yoke assembly of FIG. 2, and FIGS. 4 and 5 are a perspective view and a plan view of the frame of FIG. 2.

The acoustic transducer of FIG. 2 includes a frame 20, yoke assemblies 30, 40, and 42 fixedly mounted to the lower side of the frame 20 to form a separation space A to form a magnetic circuit, and a separation space ( A) The coil part 50 into which at least a part is inserted, the coil part 50 are mounted in the lower end (or bottom surface), the diaphragm 60 mounted in the frame 20, and the sound emission hole 72 are And a protector 70 formed to protect the diaphragm 60, and a ventilation hole 80 provided in the frame 20 below the diaphragm 60, and a leader line (not shown) of the coil part 50 is provided. It is provided with a connection terminal 90 penetrating through the side of the frame 20 or through the groove (not shown) formed in the frame 20 to be connected to the outside along the outer side of the frame 20, respectively. The connection terminal 90 allows a pair of lead wires (not shown) and lead wires (input lines and output lines) to be connected to each other from the outside. Here, the coil unit 50 and the diaphragm 60 may be collectively referred to as a diaphragm assembly.

The diaphragm 60 has a laminated structure of the first vibrating plate 62 and the second vibrating plate 64 mounted on the upper surface of the first vibrating plate 62. The central portion of the first vibrating plate 62 has a planar shape, a side dome is formed around the central portion, and a seating portion 66 fixed to the frame 20 is formed at an edge of the side dome. The second vibration plate 64 is located in the center of the first vibration plate 62 in a planar shape.

The coil unit 50 is mounted on the rear surface of the diaphragm 60, and is mounted corresponding to the center portion of the first vibration plate 62 or the edge of the second vibration plate 64 or the mounting position of the second vibration plate 64.

The yoke assembly is spaced apart from the yoke 30 including the base 30a, the side plate 30b forming a wall at the edge of the base 30a, and the side plate 30b on the upper surface of the base 30a at predetermined intervals. The magnet 40 is mounted to form the separation space A, and the top plate 42 is mounted on the upper surface of the magnet 40. The magnetic flux passes through the space A between the top plate 42 and the site plate 30b, and at least a portion of the coil part 50 is positioned at right angles to the magnetic flux. The yoke 30, the magnet 40, and the top plate 42 of the yoke assembly may be oval type, circular, square, or track type, as shown, and the diaphragm 60 and the coil part according to the shape. The form of 50 may be modified.

Magnet 40 is formed of a one-magnet type, the magnetic field efficiency is high. In particular, since the side dome of the diaphragm 60 is to occupy a smaller area than the central portion of the plane, since the magnet 40 may have a somewhat smaller area than the central portion occupying a large area, the magnet 40 of a larger area Can be mounted. Therefore, since maximizing the area (or volume) of the magnet 40 is the maximization of the magnetic circuit, the sound pressure of the acoustic transducer can be improved in the entire frequency band.

The yoke 30 has a fixing protrusion 32 for fixing to the frame 20 on the upper outer surface of the side plate 30b in parallel to the major axis direction and / or the minor axis direction. The fixing protrusion 32 may be changed in its mounting position as necessary.

In addition, the yoke 30 includes a groove 34 in a space where the lead line travels so that the lead line of the coil part 50 and the site plate 30b do not interfere with the side plate 30b. Through the provision of the grooves 34, even when the coil unit 50 vibrates and the lead wire vibrates under the influence of the vibration when the acoustic transducer is driven, the lead wire and the yoke 30 (particularly, the side plate 30b). )) Can be prevented. These grooves 34 are formed at corners where the long and short axes meet. The position of this groove 34 is once again disclosed in the detailed description of the coil section 50 below.

Next, the relationship between the radius Yr of the magnetic circuit and the radius Fr of the frame 20 for maximum generation of electromagnetic force will be described. In the case of a circular shape, the radius Yr of the magnetic circuit is designed to be about 75% to 85% of the radius Fr of the frame 20. If the radius Yr of the magnetic circuit is smaller than this design accuracy, the electromagnetic force is lowered, and thus, the sound pressure improvement cannot be improved at a low volume. If the diameter is larger than this, the size of the ventilation hole 80 is reduced to bring the sound pressure drop or the frame 20. ) Thinner thickness can affect product reliability. In the case of the Oval or square type, the uniaxial magnetic circuit radius is designed to be 75% ~ 80% of the size of the uniaxial frame.

As shown in FIGS. 4 and 5, the frame 20 includes a first receptacle 22 for receiving and mounting a yoke assembly (especially yoke 30) and a diaphragm assembly (especially diaphragm 60). And a second accommodating portion 25 accommodating and mounting the protector 70, a lead-out groove 27 allowing the lead wire of the coil part 50 to travel to the outside, and a lead wire of the coil part 50. A groove 28 is provided to advance through the groove 34 to the groove 27. However, since the frame 20 is an insulating material, the lead wire of the coil part 50 may contact the side and bottom of the lead groove 27 or 28 in the lead groove 27 or 28. The drawing groove 27 corresponds to a space formed stepped in the receiving groove 29a, the receiving groove 29a is formed in a pair corresponding to the short axis direction, the receiving groove 29b is a pair corresponding to the long axis direction Is formed. In these receiving grooves 29a and 29b, guide protrusions 68a and 68b (see Fig. 8) of the diaphragm 60 described below are accommodated.

The first accommodating part 22 and the second accommodating part 24 are divided by the partition wall 23. The partition wall 23 accommodates the fixing protrusion 32 of the yoke 30 to accommodate the yoke 30. A plurality of fixing grooves 24 for fixing are formed. In addition, the partition 23 is provided with a ventilation hole 80 through which the first accommodating part 22 and the second accommodating part 25 pass. In addition, the partition wall 23 is formed with a groove 28, the groove 28 is formed at a position corresponding to the groove 34 of the yoke 30 described above, the long and short axis of the frame 20 It is formed near the contact corner.

Since the inner surface of the first accommodating portion 22 is in contact with the outer surface of the side plate 30b of the yoke 30, and the fixing protrusion 32 is inserted into and fixed to the fixing groove 24, the yoke assembly is a frame ( 20) is fixedly mounted.

The second accommodating portion 25 has a diaphragm seating portion 26 to allow the seating portion 66 of the diaphragm 60 to be fixedly mounted. After the mounting portion 66 of the diaphragm 60 is fixedly mounted on the diaphragm seating portion 26, the protector 70 is fixedly mounted thereon.

6 and 7 are views illustrating a manufacturing process of the diaphragm.

6 is a process of forming the first diaphragm 62, the first vibrating plate 62 is a first sub diaphragm 62a containing a thermoplastic polyurethane elastomer (TPU) material for minimizing the rigidity of the diaphragm, and reliability The second sub diaphragm 62b including at least one of a material such as polyetherimide (PEI), polyester (PET) or polyester ether ketone (PEEK), polyarylate material, etc. Molded into a laminated film. In particular, since the TPU material is soft and can be attached to the mold during the molding process, the TPU material is always laminated on the upper surface of the second sub diaphragm 62b.

Through such molding, the first vibrating plate 62 is formed with a central portion C, a side dome S, and a seating portion 66. As shown in Figure 5a, instead of reducing the width of the side dome (S) instead of using a soft diaphragm material to improve the low-frequency vibration characteristics and the diaphragm of the central portion (C) having a wide plate-like structure, the diaphragm 60 The effective area is widened to improve sound pressure and induce good sound quality.

FIG. 7 shows a process of forming the second vibration plate 64, wherein the elastic layer 64c is disposed between the first and second metal plates 64a and 64b and the first and second metal plates 64a and 64b. Through the lamination, the stiffness of the center portion (C) of the first vibration plate 62 is compensated for to prevent sound distortion. Here, only one layer of the first metal plate 64a and the second metal plate 64b may be provided.

The first and second metal plates 64a and 64b are light and rigid metal layers such as aluminum, and the aluminum layers are easily deformed during fabrication, thereby compressing a styrofoam (PS) -based material having good restoring force. Use by laminating.

In addition, the second vibrating plate 64 is preferably maintained in a thickness of 0.25-0.35 mm after compression in consideration of workability. When the thickness is smaller than 0.25 mm, it becomes difficult to control when attaching to the first vibration plate 62. For example, when the guide device is used, if the thickness is too thin, the second vibration plate 64 may not be properly guided, or when using another method, it may be difficult to find the correct position of the second vibration plate 64. On the contrary, when the thickness becomes thicker than 0.35mm, not only does it occupy a lot of space, but also the rigidity of the material of the PS material, which is the elastic layer 64c, is weakened, resulting in severe dividing and a possibility of dip in the high frequency band.

8 is a cross-sectional view of another embodiment of the diaphragm of FIG. 2. As shown in FIG. 8, the diaphragm 63 has a central portion C1 having a planar opening at the center thereof, a side dome S formed at the edge of the central portion C1, and an edge of the side dome S. FIG. A seating portion 66 is formed in the groove. At this time, the overall shape of the diaphragm 63 may be circular.

The weight of the central portion C1 is reduced by forming the openings in the central portion C1, and it is possible to prevent wrinkles caused by, for example, bonding during the bonding between the central portion C1 and the second vibration plate 64. do.

9 to 14 are embodiments of the diaphragm and its performance graph.

9 shows the structure of a circular diaphragm, and FIGS. 10 and 11 are performance graphs of the diaphragm of FIG.

As shown in FIG. 10, as the width of the side dome S of the diaphragm decreases, the diaphragm stiffness increases to decrease the low frequency band, and as the width of the side dome S increases, the magnetic circuit decreases, thereby decreasing the force. As a result, the full-band sound pressure is lowered, but the stiffness is low, and the low band is reinforced again. Accordingly, it is preferable that the ratio between the radius R of the diaphragm and the width W of the side dome S in which the sound pressure is kept constant in the important sound pressure band (500 Hz to 5 kHz) is determined.

In FIG. 11, the semicircular side dome structure S having a width W of about 10 to 20% based on the diaphragm radius R maintains a constant sound pressure in the low band (500 Hz) and the high band (5 kHz). It can be seen that.

FIG. 12 corresponds to a case in which the diaphragm is an Oval type, and for a similar reason to that of FIG. 10, a short radius R and a side dome in which the sound pressure is kept constant in the sound pressure band (500 Hz to 5 kHz) important in FIG. It can be seen that the ratio between the width W of S) is preferably determined. In the present embodiment, the calculation of the W / R ratio on the basis of the short axis is that the shortening part affects the sound quality in the Oval type because the restraining force in the diaphragm of the Oval type is greater in the short part. . Therefore, even if only the condition by the short axis is satisfied in the design of the diaphragm, the condition by the long axis is almost satisfied.

In FIG. 14, a semi-circular side dome S structure having a width W of about 20 to 30% based on the length R of the short axis portion is requested. In this 20 to 30% region, the sound pressure in the low band (500 Hz) is improved, and the degree of deterioration of the sound pressure in the high band (5 kHz) is reduced.

Through this size, it is possible to maximize the effective area of the side diaphragm S to optimize the width of the diaphragm. By maximizing the effective area of the diaphragm and maximizing the size of the magnet 40 of the yoke assembly described above, the size of the magnetic circuit can be maximized.

The reason for the size limitation described above is that when the width W of the side dome S is reduced from the above-described dimension, the movement of the diaphragm is reduced due to the vibration plate restraint by the side dome S, and the width of the side dome S is If W) is wider, the effective area of the central portion S decreases, so that the sound pressure is not high, the vibration width increases, the vibration space is insufficient, and the defective rate is high.

15 to 18 are embodiments of a positional relationship between the first vibration plate, the second vibration plate, and the coil part.

As shown in FIG. 15, when attaching the second vibrating plate 64 to the central portion C of the first vibrating plate 62, a separate guide device (not shown) is used to adjust the position. To this end, a distance between the inner radius of the side dome S and the outer diameter (or edge) of the second vibration plate 64 should be secured by 0.2 mm or more.

As shown in FIG. 16, the guide step 67 is provided so that the second vibrating plate 64 is attached to the center portion c of the first vibrating plate 62 in place without using a separate guide device. Is formed. The guide terminal 67 is formed on the inner side of the side dome S, that is, formed between the side dome S and the central portion C. Accordingly, the side dome S itself serves to guide the second vibration plate 64.

As shown in FIG. 17, the second vibrating plate 64 and the coil unit 50 must overlap a predetermined degree with the central portion C of the first vibrating plate 62 interposed therebetween. This overlapping area is the hatched area B of the second vibration plate 64, and the area not overlapping corresponds to W2. Since the position of the coil part 50 is large in the rigidity of the second vibration plate 64, 50% or more of the winding width of the coil part 50 is determined based on the outer side of the second vibration plate 64. It is desirable not to be exposed to the outside of 64). That is, it is preferable that W2 / W3 becomes less than 0.5.

As shown in FIG. 18, an area corresponding to the coil part 50 is substantially included at the edge of the second vibration plate 64, that is, the width of the area B is substantially equal to the width of the coil part 50, or As shown in FIG. 19, all of the regions corresponding to the coil unit 50 may be included in the second vibration plate 64, that is, the width of the region B may be the same as the width of the coil unit 50.

20 is a detailed plan view of the diaphragm.

When the first stiffness plate 62 having a small rigidity is attached to the diaphragm seating portion 26 of the frame 20 by using an adhesive bond, the first vibration plate 62 is likely to be assembled with the deformation and may be fixed. It is hard to catch. As a result, the diaphragm 60 includes guide protrusions 68a and 68b, and the guide protrusions 68a and 68b correspond to the receiving grooves 29a and 29b of the frame 20. By being formed in the diaphragm 60, the diaphragm 60 is assembled to the frame 20 by the guide protrusions 68a and 68b.

21 is a partially enlarged view of the protector and the diaphragm of FIG. 2. As shown, the radius R1 (short axis direction) of the sound emission hole 72 formed in the protector 70 is smaller than the radius R2 (short axis direction) of the second vibration plate 64 on the center portion of the diaphragm 60. It is largely formed. Of course, the same relationship must be made in the radius in the long axis direction. That is, the sound emission hole 72 formed of the protector 70 is formed to be at least equal to or larger than the size of the corresponding second vibration plate 64.

This size relationship is required, as the thickness of the central portion of the diaphragm 60, in particular, the thickness of the second vibrating plate 64 becomes thicker, the vibration space of the second vibrating plate 64 is required. Therefore, in order to prevent mechanical interference between the second vibration plate 64 and the protector 70, the sound emission hole 72 is formed to be equal to or larger than the second vibration plate 64.

22 and 23 are partially enlarged views of the coil unit. As shown in the drawing, the coil unit 50 includes a winding unit 51 in which a coil is wound, and a pair of lead wires 52 and 54 connected to the winding unit 51.

As described above, due to the maximization of the effective areas of the magnetic circuit and the diaphragm, the inner diameter of the winding part 51 can be increased. Due to the increase in the inner diameter of the winding part 51, since the winding length per turn during winding is increased, a relatively thick coil is used to maintain the same resistance and the same height, and accordingly, the length of the coil to be subjected to the force is longer, thereby increasing the electromagnetic force. To increase. This contributes linearly to the low frequency increase, and the midrange does not increase the sound pressure significantly because the weight increases as compared to the increase in electromagnetic force. Due to the increase in the inner diameter of the coil, the width of the side dome (S) is narrowed, such as the first vibration plate 62, and the low rigid film is used to minimize the stiffness of the speaker to improve the acoustic characteristics of the low frequency band.

Lead wires 52 and 54 are respectively drawn out from the upper side of the winding part 51 of the part parallel to the long axis direction of the winding part 51, and the closest curved part of the winding part 51 is shown. Or the inflections 53, 55 at the corners. Through these inflections 53 and 55, the leader lines 52 and 54 finally go through the lead-out grooves 27 formed corresponding to the short axis direction of the frame 20, and the ends thereof are external. It is connected to the connection terminal 90 of.

The leader lines 52 and 54 travel through the space or groove 34 formed by the groove 34 when traveling above the yoke 30, and formed by the groove 28 of the frame 20. Proceed above the space or groove 28 or adjacent to or in contact with the side of the groove 28, corresponding to the inner surface of the second receiving portion 25 of the frame 20, through the withdrawal groove 27 It extends to the outside.

24 is a bottom perspective view illustrating the positional relationship between the diaphragm and the coil unit. As shown, the upper side surface of the winding portion 51 of FIG. 10A is mounted to the central portion C of the diaphragm 60, and the lead lines 52 and 54 drawn out from the winding portion 51 are side dome. The inflection parts 53 and 55 are located in the area | region corresponding to (S). Here, the leader lines 52 and 54 have a structure that proceeds without any contact with the diaphragm 60, that is, without coupling.

25 is a perspective view of another embodiment of the yoke assembly of FIG. 2, and FIGS. 26 and 27 are a perspective view and a plan view of another embodiment of the frame of FIG. 2. 25 to 27 show a circular acoustic transducer in addition to the oval acoustic transducer. The cross-sectional view of the acoustic conversion device of the Oval type in FIG. 2 is almost the same as the cross-sectional view of the circular sound conversion device.

28 and 29 are partial enlarged views of another embodiment of the coil unit, and FIG. 30 is a bottom perspective view showing the positional relationship between the diaphragm and the coil unit.

The yoke assembly of FIG. 25 includes a base 130a and a side plate 130b corresponding to the yoke 30 including the base 30a and the side plate 30b of FIG. 3, and the base 130a. A magnet 140 is mounted on the top surface to be spaced apart from the side plate 130b at a predetermined interval to form a space B, and a top plate 142 is mounted on the magnet 140.

The magnet 140 corresponds to the magnet 40 of FIG. 3, and performs the same function.

The yoke 130 has a fixing protrusion 132 corresponding to the fixing protrusion 32 of the yoke 30. According to the shape of the yoke 130, the fixing protrusion 132 may have a circular edge shape as shown in FIG. 25, may have a different shape, or may be formed at another position.

In addition, the yoke 130 includes a groove 134 corresponding to the groove 34 of FIG. 3, and when the acoustic converter is driven, the coil unit 150 vibrates and the leader line vibrates under the influence of the vibration. Even if it is, contact between the leader line and the yoke 130 (particularly, the side plate 130b) can be prevented. The groove 134 penetrates through the leader line, or the leader line proceeds to the upper side of the groove 134 to prevent the leader line from contacting the yoke 130.

In addition, the yoke 130 includes a support plate 132a between the pair of grooves 134, and the support plate 132a is inserted into the groove 129c to be mounted to the yoke 130 and the frame 120. It performs a function of coupling the liver, separating the pair of grooves 134, and limits the width of the grooves 134.

As shown in FIGS. 26 and 27, the frame 120 includes a first accommodating part 122 corresponding to the first accommodating part 22 and a second accommodating part 125 corresponding to the second accommodating part 25. ), A withdrawal groove 127 corresponding to the withdrawal groove 27, and a groove 128 corresponding to the groove 28.

The first accommodating part 22 and the second accommodating part 24 are divided by the partition wall 123. The partition wall 123 accommodates the yoke 130 by receiving the fixing protrusion 132 of the yoke 130. A plurality of fixing grooves 124 for fixing are formed. In addition, the partition wall 123 is provided with a ventilation hole 180 for penetrating the first accommodating part 122 and the second accommodating part 125. In addition, a groove 128 is formed in the partition wall 123, and the groove 128 is formed at a position corresponding to the groove 134 of the yoke 130 described above, and the leader line proceeds to the lead groove 127. It is desirable to. The lead-out groove 127 is configured to include a guide groove 129 formed to be stepped with respect to the diaphragm seating portion 126, and the lead wire is guided to the lead-out groove 127 through the groove 128 and the guide groove 129. do. This corresponds to the leader line path. The lead-out groove 127 is integrally formed with the guide groove 129 and is stepped with respect to the diaphragm seating part 126.

In addition, the groove 128 includes inner protrusions 128a and 128b inserted into the pair of grooves 134 of the yoke 130, and the yoke 130 is disposed between the inner protrusions 128a and 128b. The inner side groove 128c into which the support plate 132a of () is inserted and fixed is provided. Since the inner protrusions 128a and 128b are inserted above the groove 134, the leader line can be prevented from contacting the yoke 130. In addition, the inner groove 128c may strengthen the coupling between the yoke 130 and the frame 120.

Since the inner surface of the first accommodating part 122 is in contact with the outer surface of the side plate 130b of the yoke 130, and the fixing protrusion 132 is inserted into and fixed to the fixing groove 124, the yoke assembly is framed ( 120 is fixedly mounted.

The second accommodating part 125 includes a diaphragm seating part 126 that allows the seating part 166 of the diaphragm 160 to be fixedly mounted. After the mounting portion 166 of the diaphragm 160 is fixedly mounted to the diaphragm seating portion 126, the protector 170 is fixedly mounted thereon.

As shown in FIGS. 28 and 29, the coil unit 150 includes a winding unit 151 wound with a coil, and a pair of lead wires 152 and 154 connected to the winding unit 151. Corresponding to the winding portion 51 and the lead lines 52 and 54.

As shown, the leader lines 152 and 154 are drawn out from the upper side of the winding unit 151, that is, the lead points of the leader lines 152 and 154 are the upper side of the winding unit 151. . The leader lines 152 and 154 have inflections 153 and 155 located under the side dome S. As shown in FIG.

The leader lines 152 and 154 proceed to be substantially parallel to or slightly lower than the lead point, but the inflections 153 and 155 included during this process are located under the side dome S, The contact with the lower side of S is also prevented, and the contact with the side of the side dome S is prevented while being drawn out.

Further, through the inflections 153 and 155, the leader lines 152 and 154 travel downward from the upper side (outside or seating part 166 of the side dome S) near the drawing groove 127. Then, finally, it proceeds through the withdrawal groove 127 formed corresponding to the frame 120, and the terminal is connected to the external connection terminal 190.

The leader lines 152 and 154 travel through the space formed by the groove 134 or travel through the groove 134 when traveling on the yoke 130, and the grooves of the frame 20 ( Proceeds adjacent to or in contact with the space formed by the 128 or above the groove 128 or the side of the groove 128, and proceeds corresponding to the inner surface of the second receiving portion 125 of the frame 120, withdrawal groove It extends outward through 127.

As shown in FIG. 30, the upper side surface of the winding unit 151 of FIG. 28 is mounted at the central portion C of the diaphragm 160, and the leader lines 152 and 154 drawn out to the winding unit 151 are provided. ), The inflections 153 and 155 are located under the region corresponding to the side dome S. Here, the leader line 152, 154 has a structure that proceeds without any contact, that is, without coupling to the diaphragm 60.

31 and 32 are graphs of performance comparison between the prior art of FIG. 1 and the present invention. FIG. 31 is a comparison graph of sound pressure (SPL) between the prior art and the present invention, and FIG. 32 is a comparison graph of sound distortion (THD) between the prior art and the present invention. The diaphragm of the prior art and the diaphragm of the present invention have the same size, the prior art diaphragm is used PE series, the back volume connected to each acoustic transducer is 1cc.

As shown in FIG. 31, in the acoustic conversion device according to the present invention, a planar diaphragm laminated with high stiffness is used to minimize splitting vibration occurring as the area of the central portion of the diaphragm 60 increases, and thus, after the resonance frequency, Induces sound pressure flattening, thereby improving acoustic characteristics.

As shown in FIG. 32, due to the maximization of the magnetic circuit, the side dome is narrowed due to the increase in the inner diameter of the coil of the coil part 50, so that the rigidity of the acoustic transducer is obtained by using a low rigid film as the diaphragm 60. Minimize the to improve the acoustic characteristics of the low frequency band.

Claims (28)

1. A first vibration plate comprising a central portion that is planar and a side dome formed around the central portion; And

   And a second vibrating plate formed at the center of the first vibrating plate.
2. The method of claim 1,

   The central portion of the first vibrating plate is composed of an opening in the center and a central seating end on which the second vibration plate is mounted around the opening, and the central seating end is connected to the side dome.
3. The method according to claim 1 or 2,

   A vibration plate for an acoustic transducer, wherein a step for guiding the second vibration plate is formed inside the side dome of the first vibration plate.
4. The method according to claim 1 or 2,

   The side dome of the first vibrating plate and the second vibrating plate are spaced apart at regular intervals.
5. The method according to claim 1 or 2,

   The first vibration plate is a first sub-vibration plate containing a thermoplastic polyurethane elastomer (TPU) and a polyester (PET) material,Polyetherimide (PEI) Material, Polyether Ether Ketone A diaphragm for an acoustic transducer, comprising a laminate of a second sub-vibration plate including at least one of a PEEK material and a polyarylate material.
6. The method of claim 5,

   A diaphragm for an acoustic transducer, wherein the first sub diaphragm and the second sub diaphragm are sequentially positioned and laminated.
7. The method according to claim 1 or 2,

   The second vibrating plate is a diaphragm for an acoustic transducer, characterized in that the first and second metal layers and an elastic layer laminated between the first and second metal layers.
8. The method of claim 7, wherein

   A diaphragm for an acoustic transducer, wherein the first and second metal layers are aluminum layers.
9. The method of claim 7, wherein

   The elastic layer is a diaphragm for an acoustic transducer, characterized in that the styrofoam (PS material) layer.
10. The method of claim 1,

    The width of the side dome is 10 to 20% of the radius of the diaphragm or 20 to 30% of the radius of the diaphragm short axis diaphragm for an acoustic transducer.
11. The method according to claim 1 or 2,

    The thickness of the second vibration plate is 0.25 ~ 0.35mm diaphragm for an acoustic transducer.
12. A diaphragm according to any one of claims 1 to 11;

    A coil unit mounted around the bottom of the central portion of the diaphragm;

    A magnetic circuit for causing magnetic flux to be bridged at right angles to at least a portion of the coil portion;

    A frame having a first accommodating portion accommodating a magnetic circuit at a lower side thereof and a second accommodating portion accommodating a diaphragm at an upper side thereof; And

    And a protector for protecting the diaphragm on the upper side of the frame.
13. The method of claim 12,

    The coil unit attached to the rear surface of the diaphragm has a first vibration plate in between, and the second vibration plate is mounted so that a predetermined width or more overlap with the second vibration plate.
14. The method of claim 12,

    Sound conversion device, characterized in that the predetermined degree is 50% or more.
15. The method of claim 12,

    The protector is an acoustic transducer, characterized in that it comprises a sound emitting hole having a size equal to or wider than the center of the diaphragm or the second vibration plate.
16. The method of claim 12,

    A lead-out groove is formed in one end of the frame, and the lead wire of the coil unit is bent at least one or more times under the side dome to advance to the lead-out groove.
17. A diaphragm assembly including a central portion that is a flat plate, a diaphragm having a thickness thinner than the thickness of the central portion, and a side dome formed around the central portion, and a coil portion mounted around a bottom surface of the central portion;

    A magnetic circuit for causing magnetic flux to be bridged at right angles to at least a portion of the coil portion;

    A frame having a first accommodating part accommodating a magnetic circuit at a lower side thereof and a second accommodating part accommodating a diaphragm assembly so that the coil part is disposed between the spaced spaces at an upper side thereof;

    A sound converting device comprising a protector for protecting the diaphragm assembly on the upper side of the frame.
18. The method of claim 17,

    The diaphragm includes a first vibration plate having a central portion and a side dome, and a second vibration plate mounted on an upper surface of the central portion of the first vibration plate.
19. The method of claim 17,

    The diaphragm is composed of a third vibration plate made of a side dome having an opening in the center, and a center seat end around the opening, and a fourth vibration plate mounted on the upper surface of the center seat end to form a center part. Device.
20. The method of claim 17,

    A lead-out groove is formed in one end of the frame, and the lead wire of the coil unit is bent at least one or more times under the side dome to advance to the lead-out groove.
21. The method of claim 20,

    The sound converting apparatus includes a lead line path for advancing the lead line of the coil unit to the lead-out groove and preventing contact with the magnetic circuit.
22. The method of claim 21,

    The magnetic circuit includes a yoke consisting of a magnet, a top plate mounted above the magnet, and a base on which the magnet is mounted, and a side plate mounted so as to form a space between the sides of the magnet around the base. And a first groove formed on an upper side of the side plate of the yoke, and the leader line passes through the inside of the first groove or travels above the first groove.
23. The method according to any one of claims 20 to 22,

    The leader line path is formed adjacent to the first receiving portion of the frame, and has a second groove for guiding the leader line to the leader groove.
24. The method of claim 23, wherein

    The second groove is formed in the partition wall separating the first accommodating portion and the second accommodating portion.
25. The method of claim 23, wherein

    The lead-out groove is a sound conversion device, characterized in that formed stepped relative to the diaphragm seating portion formed in the frame.
26. The method of claim 23, wherein

    The first and second grooves are acoustic conversion device, characterized in that formed to face each other.
27. The method of claim 23, wherein

    And the first groove is a pair of grooves separated from each other by a support plate, and the second groove has an inner groove for receiving the support plate.
28. The method of claim 23, wherein

    The second groove has an inner protrusion which is inserted into the first groove is mounted.

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