Speaker device

The present invention relates to a speaker device, and more specifically, to a speaker device in which a plurality of speaker units are arranged in a line, such as a line speaker.

Conventionally, a speaker device such as a line speaker in which a plurality of speaker units are arranged in a line is generally known (see, for example, Patent Document 1). FIG. 25 is a diagram showing the structure of the speaker device which is a line speaker, FIG. 25 (a) is a front view of the speaker device, and FIG. 25 (b) is a structural cross-sectional view of the side of the speaker device. is there.

The speaker device 9 includes a cabinet 91 and a plurality of speaker units 92. Each of the plurality of speaker units 92 is attached to the cabinet 91 so that the front surface faces the front direction of the cabinet 91. As shown in FIG. 25A, the speaker units 92 are arranged in a straight line when viewed from the front of the speaker device 9, and the arrangement direction is parallel to the vertical direction of the speaker device 9. Further, as shown in FIG. 25B, the speaker units 92 are arranged linearly when viewed from the side surface of the speaker device 9. It should be noted that each speaker unit 92 has a structural cross section similar to that of a normal electrodynamic speaker, and FIG. 25 (b) shows the structural cross section of each speaker unit 92 in abbreviated form.

With such a structure, a line sound source is approximately produced in the arrangement direction of each speaker unit 92. Therefore, when the speaker device 9 is used in a home where the listening position is a short distance, the sound field becomes uniform at the listening position in the arrangement direction of each speaker unit 92, and there is no sound field in the direction perpendicular to the arrangement direction. Become directional. That is, the listening area can be expanded as compared with the case of using a speaker device including one speaker unit.

<p><patcit num="1"><text>Japanese Unexamined Patent Publication No. 2004-320100</text></patcit></p>

<p> However, the speaker device 9 has a problem that a peak dip occurs in the sound pressure frequency characteristic of the reproduced sound at the listening position due to the phase interference between the plurality of speaker units 92, and the sound quality deteriorates in the high frequency range.</p><p> Hereinafter, the sound quality deterioration due to the phase interference will be specifically described with reference to FIGS. 26 and 27. FIG. 26 is a diagram showing the difference in sound wave propagation between the line sound source and the point sound source array, FIG. 26 (a) shows the state of sound wave propagation of the line sound source, and FIG. 26 (b) shows the sound wave propagation of the point sound source array. It shows the state of. In FIGS. 26 (a) and 26 (b), the solid line and the dotted line arranged in the arrow direction indicate sound waves having opposite phases to each other. Figure 27 shows the sound pressure frequency characteristics (calculated values) of the reproduced sound at a certain listening position of a line sound source with a length of 1.5 [m] and a point sound source array with an array length of 1.5 [m] (number of point sound sources N = 16). ).</p><p> When the speaker device 9 produces an ideal line sound source as shown in FIG. 26 (a) over the entire reproduction frequency band, the sound pressure frequency characteristic at the listening position is high as shown by the solid line in FIG. 27. It has an attenuation characteristic of -6dB / octave in the range, and the change of peaks and valleys becomes gradual. However, the line sound source produced by the speaker device 9 is only an approximation. In reality, as shown in FIG. 26 (b), a plurality of sound sources close to point sound sources are arranged at intervals. Due to this interval, phase interference occurs remarkably near a specific frequency. Specifically, as shown by the dotted line in FIG. 27, the sound pressure frequency characteristic at the listening position causes a sharp drop in sound pressure (dip) in the high frequency range, and the peaks and valleys change drastically.</p><p> Conventionally, a method of eliminating the peak dip by equalizing the frequency characteristic of the acoustic signal or the like has been proposed for the sound quality deterioration caused by such phase interference. However, since the frequency at which the peak dip occurs greatly changes due to a slight difference in the listening position, it is difficult to eliminate the peak dip, and it is not possible to suppress the deterioration of sound quality due to phase interference.</p><p> Therefore, the present invention is a speaker device in which a plurality of speaker units are arranged in a line, and can suppress sound quality deterioration due to phase interference when used in a home where the listening position is a short distance. The purpose is to provide.</p>

<p> The present invention has been made to solve the above problems, and the speaker device according to the present invention is a speaker device in which a plurality of speaker units are arranged in a line when viewed from the front, and the adjacent speaker units are arranged. At least one of the intervals between the effective vibration regions is set to a predetermined length, and the predetermined length is the distance from the end of one effective vibration region forming the interval to the listening position and the other. The length is set so that the difference from the distance from the end of the effective vibration region of the speaker unit to the listening position is shorter than half of the shortest wavelength of the reproduced sound of each speaker unit.</p><p> With such a configuration, it is possible to prevent the phase interference of the sound reproduced from at least two speaker units sandwiching the interval set to a predetermined length when the sound is used in a home where the listening position is a short distance. .. As a result, deterioration of sound quality due to phase interference can be suppressed as compared with the conventional case.</p><p> Preferably, each speaker unit has a diaphragm and an edge provided on the outer periphery of the diaphragm, and among the speaker units, two speaker units having a predetermined length and sandwiching an interval thereof are used. It is preferable that the edges are arranged so as to overlap each other within the interval.</p><p> Further, preferably, the speaker units are arranged in an arc shape when viewed from the side surface of the speaker device. In this case, when the array length of each speaker unit is L, the radius of curvature indicated by the arc is R, and the listening distance from the center of the array of each speaker unit to the listening position is D, (R + D). ) × (L / R) D should hold. Alternatively, when the array length of each speaker unit is L and the radius of curvature indicated by the arc is R, when the listening distance from the center of the array of each speaker unit to the listening position is 5 m or less, (L / R). ) 1.5 may hold. Alternatively, when the array length of each speaker unit is L and the radius of curvature indicated by the arc is R, the listening distance from the center of the array of each speaker unit to the listening position is 3 m, (L / R). The relationship of 0.5 may be established.</p><p> Further, preferably, the speaker units are arranged linearly when viewed from the side surface of the speaker device. In this case, the input acoustic signal is further delayed by a delay time set corresponding to each speaker unit, and the delayed acoustic signal is further provided with a delay means for outputting the delayed acoustic signal to the corresponding speaker unit. The time is the time for the reproduced sound to be transmitted from the arrangement position of the corresponding speaker unit to the arrangement position of the corresponding speaker unit when it is assumed that each speaker unit is arranged in an arc shape when viewed from the side surface of the speaker device. Should be set to. Further, each speaker unit is tilted with respect to the linear arrangement direction seen from the side surface of the speaker device by an angle corresponding to each arrangement position when it is assumed that the speaker units are arranged in an arc shape when viewed from the side surface of the speaker device. You may.</p><p> Also preferably, calibration speaker units are attached may further comprise a vignette.</p><p> It is also preferable to further include one frame to which each speaker unit is attached, and each speaker unit is provided with a diaphragm and an edge provided on the outer periphery of the diaphragm to vibrately support the diaphragm with respect to the frame. It is good to have. In this case, further, among the speaker units, the two speaker units sandwiching the interval set to a predetermined length are attached to the frame so as to overlap a part of the edges of each other within the interval. Good.</p><p> Further, preferably, each speaker unit has its own diaphragm, and one frame to which each speaker unit is attached and each diaphragm are oscillatedly supported with respect to the frame by surrounding the outer periphery of each diaphragm. It would be nice to have one more edge to do.</p><p> Further, preferably, the area of the effective vibration region of each speaker unit is 4π [cm].²] It may be more than that. Further, the drive system of each speaker unit may be any one of an electrokinetic type, a piezoelectric type, an electrostatic type, and an electromagnetic type. Further, each speaker unit may have a diaphragm having any one of a circular shape, an elliptical shape, and a rectangular shape.</p><p> The present invention is also directed to a video device, and the video device according to the present invention includes the speaker device and a housing in which the speaker device is arranged.</p>

<p> According to the present invention, there is a speaker device in which a plurality of speaker units are arranged in a line, and it is possible to suppress deterioration of sound quality due to phase interference when the speaker device is used in a home where the listening position is a short distance. Can be provided.</p>

<figref num="1">The figure which shows the structure of the speaker apparatus which concerns on Embodiment 1.</figref><figref num="2">Schematic diagram showing the effective vibration region of the speaker unit 12 and the interval between the effective vibration regions.</figref><figref num="3">The figure for demonstrating the condition of the distance difference Q which concerns on Embodiment 1.</figref><figref num="4">The figure which extracted the part showing the vibration region of the speaker unit 12 from FIG.</figref><figref num="5">The figure which shows the structure of the speaker apparatus which concerns on Embodiment 2.</figref><figref num="6">The figure which shows the structure of the speaker module 22</figref><figref num="7">The figure which shows the structure of the speaker apparatus which concerns on Embodiment 3.</figref><figref num="8">The figure for demonstrating the condition of the distance difference Q which concerns on Embodiment 3.</figref><figref num="9">The figure which showed the arrangement length L and the radius of curvature R of a speaker unit 32</figref><figref num="10">The figure which shows the sound pressure frequency characteristic when the interval d is changed while the array length L is constant.</figref><figref num="11">The figure which shows the directivity of the speaker devices 1 and 3 having the same array length L in the array direction.</figref><figref num="12">The figure which shows the directivity in the arrangement direction of the speaker apparatus 3 for each frequency.</figref><figref num="13">Diagram showing the directivity that serves as the standard for standardization</figref><figref num="14">Diagram showing the contents of equation (4)</figref><figref num="15">The figure which shows the result of having confirmed by the numerical calculation that the sound pressure difference becomes 6 [dB] or less.</figref><figref num="16">The figure which showed the directivity in the arrangement direction of the speaker apparatus 3 for each frequency when the listening distance D is 3 [m].</figref><figref num="17">The figure which shows the structure of the speaker apparatus which concerns on Embodiment 4.</figref><figref num="18">The figure which shows the structure of the speaker module 42</figref><figref num="19">The figure which shows the structure of the speaker apparatus which concerns on Embodiment 5.</figref><figref num="20">Diagram for explaining how to set the delay time</figref><figref num="21">The figure which shows how the inclination of a speaker unit 52-1 ~ 52-20 is changed according to an arc-shaped arrangement.</figref><figref num="22">Front view of the flat-screen TV according to the sixth embodiment</figref><figref num="23">The figure which shows the structure of the speaker apparatus 63</figref><figref num="24">The figure which shows the other structure of the speaker apparatus 63</figref><figref num="25">The figure which shows the structure of the conventional speaker apparatus</figref><figref num="26">Diagram showing the difference in sound wave propagation between a line sound source and a point sound source array</figref><figref num="27">A diagram showing the sound pressure frequency characteristics (calculated values) of the reproduced sound at a certain listening position of a line sound source having a length of 1.5 [m] and a point sound source array having a length of 1.5 [m] (number of point sound sources N = 16).</figref>

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(Embodiment 1) FIG. 1 is a diagram showing a structure of a speaker device according to a first embodiment of the present invention, FIG. 1 (a) is a front view of the speaker device, and FIG. 1 (b) is a side view of the speaker device. It is a structural sectional view of.

The speaker device 1 includes a cabinet 11 and a plurality of speaker units 12, and is installed in a place where the listening position is close, such as in a home. In the example of FIG. 1, the speaker device 1 includes 20 speaker units 12, but is not limited thereto. Each speaker unit 12 is an electrodynamic speaker, and is attached to the cabinet 11 so that the front surface faces the front direction of the cabinet 11. As shown in FIG. 1A, the speaker units 12 are arranged in a straight line when viewed from the front of the speaker device 1, and the arrangement direction is parallel to the vertical direction of the speaker device 1. Further, as shown in FIG. 1B, the speaker units 12 are arranged linearly when viewed from the side surface of the speaker device 1. Each speaker unit 12 has a structural cross section similar to that of a normal electrodynamic speaker, and FIG. 1B shows the structural cross section of the speaker unit 12 in abbreviated form.

The operation of the speaker device 1 configured as described above will be described. The acoustic signal output from the audio amplifier (not shown) is input to each of the plurality of speaker units 12 via a cable (not shown). Here, it is assumed that acoustic signals of the same level are input to the plurality of speaker units 12. The acoustic signal is converted into mechanical vibration by each speaker unit 12, and is radiated into the air as reproduced sound from the diaphragm in front of each speaker unit 12. Examples of the acoustic signal include a monaural audio signal, a stereo audio signal, and a multi-channel audio signal.

Hereinafter, a method of arranging the speaker units 12 according to the present embodiment will be described.

In an ideal line sound source, since the sound source is linear, the phase of the sound wave that reaches the listening position from an arbitrary point on the sound source continuously changes according to the position of the arbitrary point. Therefore, as shown in FIG. 27, the sound pressure frequency characteristic of the reproduced sound at the listening position has a gradual change in peaks and valleys in the high frequency range. On the other hand, when a plurality of sound sources close to a point sound source are arranged at intervals, the phase of the sound wave reaching the listening position from the sound source changes discontinuously according to the position of the sound source due to the interval. Therefore, as shown in FIG. 27, the sound pressure frequency characteristic of the reproduced sound at the listening position has a large change in peaks and valleys in the high frequency range. In particular, the difference between the distance from one end of the distance between adjacent sound sources to the listening position and the distance from the other end of the distance to the listening position (hereinafter referred to as the distance difference Q) is more than half of the wavelength of the reproduced sound. In the frequency band, the sound pressure drops significantly due to the cancellation of the opposite phase sounds, causing a peak dip.

Therefore, in the present embodiment, a plurality of sound sources, that is, a plurality of speaker units 12 are arranged so that the distance difference Q is less than half the wavelength of the reproduced sound at the upper limit frequency of the reproduction band of the speaker unit 12. As a result, the sound source produced by the speaker device 1 can be brought closer to the ideal line sound source, and the peak dip due to phase interference can be prevented from occurring in the reproduction band. That is, it is possible to prevent deterioration of sound quality due to phase interference. Hereinafter, the distance difference Q will be specifically described.

The condition of the distance difference Q is obtained by using the effective vibration region of the speaker unit 12 and the distance between the effective vibration regions. With reference to FIG. 2, the effective vibration region of the speaker unit 12 and the interval between the effective vibration regions will be specifically described. FIG. 2 is a schematic diagram showing the effective vibration region and the interval between the effective vibration regions of the speaker unit 12. In addition, in FIG. 2, two speaker units 12 are illustrated, and for convenience of explanation, the reference code of the upper speaker unit is 12_{n + 1}And the reference code of the lower speaker unit is 12_nIt is said. Speaker unit 12_n、12_{n + 1}Each includes a frame 121, an edge 122, and a vibrating plate 123. Although not shown in FIG. 2, the speaker unit 12_n、12_{n + 1}Each of them is equipped with a voice coil and a magnetic circuit. The edge 122 includes a roll portion 1221 and an adhesive allowance 1222. The bonding allowance 1222 is bonded to the frame 121, and the inner circumference of the roll portion 1221 is bonded to the outer circumference of the diaphragm 123. Speaker unit 12_nDotted circle S marked above_nIs the speaker unit 12_nIs the vibration region that actually vibrates, and the speaker unit 12_{n + 1}Dotted circle S marked above_{n + 1}Is the speaker unit 12_{n + 1}Is the vibration region that actually vibrates. In FIG. 2, the vibration region S_n, S_{n + 1}Let r be the effective radius of both, and the vibration region S_nTop edge and vibration region S_{n + 1}The distance between the lower ends of is d.

Effective vibration region SA_nIs the central axis O perpendicular to the array direction_nThe vibration area S_nIn the state of matching with, the central axis O_nThe magnitude of the direction is the vibration region S_nWhile setting the same "2r" as, the vibration region S_nIt is a region where the size in the array direction is set to "πr / 2" so that it has the same area as. Similarly, the effective vibration region SA_{n + 1}Is the central axis O perpendicular to the array direction_{n + 1}The vibration area S_{n + 1}In the state of matching with, the central axis O_{n + 1}The magnitude of the direction is the vibration region S_{n + 1}While setting the same "2r" as, the vibration region S_{n + 1}It is a region where the size in the array direction is set to "πr / 2" so that it has the same area as. In the example of FIG. 2, the vibration region S_n, S_{n + 1}Since is circular, the distance between the vibration regions becomes larger as the distance from the central axis of the vibration region parallel to the arrangement direction is set to the minimum. In order to take this effect into consideration, the effective vibration region SA formed so that the distance between the vibration regions is constant in the direction perpendicular to the arrangement direction as described above._n, SA_{n + 1}Is defined. If the vibration region is rectangular, the effective vibration region is the vibration region itself. Effective vibration region SA_n, SA_{n + 1}The interval de between them is expressed by Eq. (1).

<maths num="1"><img file="JP5145334B2_D0001.tif" /></maths>

Next, the condition of the distance difference Q will be specifically described with reference to FIG. FIG. 3 is a diagram for explaining the condition of the distance difference Q. In FIG. 3, the front surface of the cabinet 11 is placed on the Y axis, and the array length (straight line length) of the speaker unit 12 is L. Listening position P₁Is the center P of the array of speaker units 12₀Located on the X-axis passing through, listening position P₁And center P₀Let D be the listening distance between them. Also, the center P₀SA the effective vibration area of the speaker unit 12 arranged in₀And the effective vibration area is SA₀The nth effective vibration region counted in the positive direction of the Y-axis is SA_nAnd the n + 1th effective vibration region is SA_{n + 1}And. Also, the effective vibration region SA_nCenter P from the top of₀Distance to y_nAnd. Effective vibration region SA_nTop edge and effective vibration area SA_{n + 1}The distance between the lower ends of is the distance de shown in FIG. At this time, the distance difference Q is the effective vibration region SA forming the interval de._nTop edge and listening position P₁Distance to l_nAnd the effective vibration region SA_{n + 1}Lower end and listening position P₁Distance to l_{n + 1}This difference may be less than half the wavelength of the reproduced sound at the upper limit frequency of the reproduction band of the speaker unit 12. The specific condition of the distance difference Q is expressed by Eq. (2), where λ is the wavelength of the reproduced sound at the upper limit frequency of the reproduction band of the speaker unit 12.

<maths num="2"><img file="JP5145334B2_D0002.tif" /></maths>

As described above, according to the present embodiment, the plurality of speaker units 12 are arranged so that the distance difference Q is less than half the wavelength of the reproduced sound at the upper limit frequency of the reproduction band of the speaker unit 12. As a result, the sound source produced by the speaker device 1 can be brought closer to the ideal line sound source, and the peak dip due to phase interference can be prevented from occurring in the reproduction band. That is, it is possible to prevent deterioration of sound quality due to phase interference. Further, according to the present embodiment, since the speaker device 1 is installed in a place where the listening position is close, such as in a home, the listening area is larger than that in the case where the speaker device including one speaker unit is installed. It can be expanded.

In the above description, all of the plurality of speaker units 12 are arranged based on the interval de when the distance difference Q satisfies the equation (2), but the present invention is not limited to this. If at least two speaker units 12 are arranged based on the interval de when the distance difference Q satisfies the equation (2), the deterioration of sound quality due to phase interference can be suppressed as compared with the conventional case. However, this is limited to the case where the distance between the speaker units 12 other than the above two speaker units 12 is not larger than before.

Further, in the above description, it is assumed that the acoustic signals of the same level are input to the plurality of speaker units 12, but the acoustic signals may be input at different levels for each speaker unit 12.

Further, in the above description, the front shape of the diaphragm 123 of the speaker unit 12 is circular, but the front shape of the diaphragm 123 may be any shape, for example, a rectangle or an ellipse. Further, although the cross-sectional shape of the diaphragm 123 is a cone shape, the cross-sectional shape of the diaphragm 123 may be any shape, for example, a flat shape.

Further, in the above description, the speaker units 12 are arranged in a straight line when viewed from the front of the speaker device 1, but the present invention is not limited to this. The speaker units 12 may be arranged in a curved line when viewed from the front of the speaker device 1. Further, each speaker unit 12 is attached to the cabinet 11 so that the front surface is parallel to the arrangement direction, but the present invention is not limited to this. Each speaker unit 12 may be attached to the cabinet 11 so that the front surface is inclined with respect to the arrangement direction.

Further, in the above description, the drive system of the speaker unit 12 is an electrokinetic type, but the drive system may be any of a piezoelectric type, an electrostatic type, an electromagnetic type and the like.

Further, in the above description, a specific numerical example has not been given for the effective radius of the vibration region of the speaker unit 12, but any value may be used. For example, the effective radius may be 2 [cm] or more. In this case, the area of the effective vibration region is 4π [cm].²] That's all.

(Embodiment 2) In the speaker device 1 according to the first embodiment, there is a limit in reducing the interval d due to its structure. FIG. 4 is a diagram in which a portion showing the vibration region of the speaker unit 12 is extracted from FIG. In FIG. 4, where w is the width of the edge 122, the vibration region S_nSpeaker unit 12 from the top of_nWidth to the top of edge 122, vibration region S_{n + 1}Speaker unit 12 from the bottom of_{n + 1}The width of the edge 122 to the lower end is w / 2. Also, the speaker unit 12_nIn, the width from the upper end of the edge 122 to the upper end of the frame 121 is W, and the speaker unit 12_{n + 1}Let W be the width from the lower end of the edge 122 to the lower end of the frame 121. At this time, the interval d is the sum of w and 2W, and it is structurally difficult to make the interval d smaller than the sum of w and 2W. For example, speaker unit 12_n、12_{n + 1}When the caliber (nominal) of is 8 [cm], the interval d is at least about 30 [mm]. As described above, in the speaker device 1 according to the first embodiment, there is a limit in reducing the interval d due to its structure. Therefore, in the second embodiment, a speaker device capable of making the interval d smaller than that of the first embodiment and easily setting the interval de to a value satisfying the equation (2) will be described. Specifically, in the speaker device according to the second embodiment, the speaker unit is attached to the cabinet so that the adhesive margins of the adjacent edges overlap each other. Other structures and operations are the same as those of the speaker device 1, and description thereof will be omitted here.

5A and 5B are views showing the structure of the speaker device according to the second embodiment of the present invention, FIG. 5A is a front view of the speaker device, and FIG. 5B is a side view of the speaker device. It is a structural sectional view of.

The speaker device 2 includes a cabinet 21 and a plurality of speaker modules 22, and is installed in a place where the listening position is close, such as in a home. In the example of FIG. 5, the speaker device 2 includes five speaker modules 22, but is not limited thereto. Each speaker module 22 contains four speaker units, respectively, and is mounted on the front of the cabinet 21. As shown in FIG. 5A, the speaker units are arranged in a straight line when viewed from the front of the speaker device 2, and the arrangement direction is parallel to the vertical direction of the speaker device 2. Further, as shown in FIG. 5B, the speaker units are arranged linearly when viewed from the side surface of the speaker device 2. Note that FIG. 5B shows the structural cross section of the speaker module 22 in abbreviated manner, and a detailed structural cross section is shown in FIG.

6A and 6B are views showing the structure of the speaker module 22, FIG. 6A is a front view of the speaker module 22, and FIG. 6B is a side structural sectional view of the speaker module 22. .. The speaker module 22 includes a frame 221 and four speaker units 12a. The frame 221 includes a front plate 2211, a support member 2212, and a connecting member 2213. The front plate 2211 and the support member 2212 are formed in a straight line as shown in FIG. 6 (b). A connecting member 2213 for connecting the front plate 2211 and the support member 2212 is provided between the front plate 2211 and the support member 2212. The speaker unit 12a has a structure in which the frame 121 is removed from the speaker unit 12 shown in FIG. 1, and includes an edge 122, a diaphragm 123, a voice coil bobbin 124, a voice coil 125, a yoke 126, a magnet 127, and a plate 128. Have. The edge 122 includes a roll portion 1221 and an adhesive allowance 1222. The adhesive margin 1222 is adhered to the front plate 2211, and the inner circumference of the roll portion 1221 is adhered to the outer circumference of the diaphragm 123. As a result, the diaphragm 123 is oscillatedly supported by the front plate 2211. A part of the adjacent bonding allowance 1222 is bonded to the front plate 2211 in an overlapping manner as shown in the enlarged view surrounded by the dotted line in FIG. 6 (b). The inner circumference of the diaphragm 123 is adhered to one end of the voice coil bobbin 124 arranged in the through hole formed in the support member 2212. The voice coil 125 is wound around the voice coil bobbin 124. The yoke 126 is attached to the support member 2212 so as to surround the through hole formed in the support member 2212. One side of the magnet 127 is glued to the inner surface of the yoke 126, and the other side is glued to the plate 128. A magnetic gap is formed between the side surface of the plate 128 and the inner surface of the yoke 126, and the voice coil 125 is arranged in the magnetic gap. The dotted circle on the speaker unit 12a is the vibration region of the speaker unit 12a.

As described above, in the present embodiment, as shown in FIG. 6A, the speaker units 12a are arranged so as to overlap each other's adhesion allowance 1222. As a result, the distance d between the vibration regions becomes smaller than the distance d shown in FIG. That is, the interval de can be made smaller than that in the case of the speaker device 1. Therefore, according to the present embodiment, the interval de can be easily set to a value satisfying the equation (2), and the deterioration of sound quality due to phase interference can be easily prevented.

Further, in the present embodiment, since the edge 122 exists between the diaphragms 123 of each speaker unit 12a, the diaphragms 123 vibrate independently of each other. Therefore, it is possible to prevent unnecessary resonance generated by the vibrations of the diaphragms 123 being transmitted to each other, and it is possible to vibrate all the speaker units 12a in the same phase.

In the above description, the speaker module 22 includes four speaker units 12a, but the present invention is not limited to this. For example, the speaker module 22 may include 20 speaker units 12a, and the speaker device 2 may include one speaker module 22.

Further, in the above description, each speaker unit 12a has an edge 122, but the present invention is not limited to this. Each edge 122 may be integrally molded in a state where the bonding allowance 1222 is overlapped with each other, and the integrally molded edge may be shared by each speaker unit 12a.

Further, in the above description, all of the speaker units 12a are arranged so as to overlap each other's adhesion allowance 1222, but only the two speaker units 12a are arranged so as to overlap each other's adhesion allowance 1222. May be good. Further, all of the speaker units 12a may be arranged so as not to overlap each other's adhesion margin 1222. Even in this case, each speaker unit 12a shares one frame 221. Therefore, the distance d between the vibration regions of each speaker unit 12a can be made smaller than that in the case where each speaker unit 12a includes a frame.

Further, in the above description, the cabinet 21 is one of the components of the speaker device 2, but the cabinet 21 may be removed from the components of the speaker device 2. In this case, the speaker device 3 becomes the speaker module 22 itself.

Further, in the above description, the explanation is made on the premise that the distance difference Q satisfies the condition of the equation (2), but even if the equation (2) is not satisfied, the adhesive margins of the adjacent edges overlap each other, so that the adjacent edges are adjacent to each other. It is possible to suppress the deterioration of sound quality due to phase interference as compared with the case where the adhesive margins do not overlap each other.

(Embodiment 3) In the speaker device 1 according to the first embodiment, as shown in FIG. 1 (b), a plurality of speaker units 12 are arranged linearly when viewed from the side surface of the speaker device 1. On the other hand, in the third embodiment, a case where a plurality of speaker units are arranged in an arc shape when viewed from the side surface of the speaker device will be described. Other structures and operations are the same as those of the speaker device 1, and description thereof will be omitted here.

FIG. 7 is a diagram showing the structure of the speaker device according to the third embodiment of the present invention, FIG. 7 (a) is a front view of the speaker device, and FIG. 7 (b) is a side view of the speaker device. It is a structural sectional view of.

The speaker device 3 includes a cabinet 31 and a plurality of speaker units 32, and is installed in a place where the listening position is close, such as in a home. In the example of FIG. 7, the speaker device 3 includes 20 speaker units 32, but is not limited thereto. Each speaker unit 32 is attached to the cabinet 31 so that the front surface faces the front direction of the cabinet 31. As shown in FIG. 7A, the speaker units 32 are arranged in a straight line when viewed from the front of the speaker device 3, and the arrangement direction is parallel to the vertical direction of the speaker device 3. Further, as shown in FIG. 7B, the speaker units 32 are arranged in an arc shape when viewed from the side surface of the speaker device 3. Each speaker unit 32 has a structural cross section similar to that of a normal electrodynamic speaker, and FIG. 7B shows the structural cross section of the speaker unit 32 in abbreviated form.

Hereinafter, a method of arranging the speaker units 32 according to the present embodiment will be described.

In the present embodiment, as in the first embodiment, a plurality of sound sources, that is, a plurality of speaker units 32 are arranged so that the distance difference Q is less than half the wavelength of the sound at the upper limit frequency of the reproduction band of the speaker unit 32. ing. As a result, the sound source produced by the speaker device 3 can be brought closer to the ideal line sound source, and the peak dip due to phase interference can be prevented from occurring in the reproduction band. That is, it is possible to prevent deterioration of sound quality due to phase interference.

Here, as shown in FIG. 7B, the speaker units 32 are arranged in an arc shape when viewed from the side surface of the speaker device 3, so that the condition of the distance difference Q has been described in the first embodiment. It will be expressed by an equation different from equation (2). Hereinafter, the condition of the distance difference Q according to the third embodiment will be specifically described with reference to FIG. FIG. 8 is a diagram for explaining the condition of the distance difference Q according to the third embodiment. The effective vibration region and the interval between the effective vibration regions of the speaker unit 32 are the same as those described in FIG. 2, and thus the description thereof will be omitted here. In FIG. 8, the center P of the arrangement of the speaker unit 32₀Is the origin on the Y axis, and the array length (arc length) of the speaker unit 32 is L. Listening position P₁Is the center P₀Located on the X-axis passing through, listening position P₁And center P₀Let D be the listening distance between them. Also, the center P₀SA the effective vibration area of the speaker unit 32 placed in₀And the effective vibration area is SA₀The nth effective vibration region counted in the positive direction of the Y-axis is SA_nAnd the n + 1th effective vibration region is SA_{n + 1}And. Also, the effective vibration region SA_nSA is the area when is placed symmetrically with respect to the X axis._nWhen set to', the effective vibration region SA_nFrom the top of the area SA_nL for the length of the arc to the bottom of'_nAnd. Effective vibration region SA_nAnd effective vibration region SA_{n + 1}The interval between them is the interval de shown in FIG. 8, and is expressed by the above equation (1). Also, let R be the radius of curvature of the arc. At this time, the distance difference Q is the effective vibration region SA forming the interval de._nTop edge and listening position P₁Distance to l_nAnd the effective vibration region SA_{n + 1}Lower end and listening position P₁Distance to l_{n + 1}This difference may be less than half the wavelength of the reproduced sound at the upper limit frequency of the reproduction band of the speaker unit 32. The specific condition of the distance difference Q is expressed by Eq. (3), where λ is the wavelength of the reproduced sound at the upper limit frequency of the reproduction band of the speaker unit 32.

<maths num="3"><img file="JP5145334B2_D0003.tif" /></maths>

When the distance difference Q satisfies the equation (3), the length of the interval d of the equation (1) is 8 [cm] for the diameter (nominal) of the speaker unit 32 (that is, the effective diameter of the vibration region of the speaker unit 32 is 6). [cm]), and as shown in FIG. 9, when the arrangement length L of the speaker unit 32 is 1.5 [m] and the radius of curvature R is 3 [m], 0.0134 [m] = 13.4 [mm]. .. FIG. 9 is a diagram showing the array length L and the radius of curvature R of the speaker unit 32. The Z-axis shown in FIG. 9 is an axis orthogonal to the X-axis and the Y-axis shown in FIG. 8, respectively. In addition, FIG. 10 shows the sound pressure frequency characteristics when the interval d is changed while the array length L is constant. In the sound pressure frequency characteristic of FIG. 10, the upper limit frequency of the reproduction band is set to 10 [kHz], and the listening position P₁The center of the array of speaker units 32 P₀The calculated value when the position is set to 3 [m] from. As shown in FIG. 10, it can be seen that the smaller the interval d in Eq. (1) (that is, the smaller the interval de), the smaller the distance difference Q, and therefore the peak dip due to phase interference is less likely to occur. ..

As described above, according to the present embodiment, the plurality of speaker units 32 are arranged so that the distance difference Q is less than half the wavelength of the reproduced sound at the upper limit frequency of the reproduction band of the speaker unit 12. As a result, the sound source produced by the speaker device 3 can be brought closer to the ideal line sound source, and the peak dip due to phase interference can be prevented from occurring in the reproduction band. That is, it is possible to prevent deterioration of sound quality due to phase interference.

Here, in the speaker device 1 described above, the speaker units 12 are arranged linearly when viewed from the side surface of the speaker device 1. Therefore, in the speaker device 1 described above, the shorter the wavelength of the reproduced sound with respect to the arrangement length L of the speaker unit 12, the sharper the directivity in the arrangement direction becomes, and the range in which a desired sound field can be obtained (hereinafter, sound field). The range) becomes narrower. Therefore, in the range where the wavelength of the reproduced sound is short (that is, in the high range), it is necessary to increase the array length L in order to give the desired sound field range to the directivity in the array direction by using the speaker device 1 described above. .. For example, when reproducing sound in a frequency band of 10 [kHz] or less at a short distance, it is necessary to set the array length L to 3 [m], and it is not realistic to use the speaker device 1 for home use.

On the other hand, in the speaker device 3 according to the third embodiment, the speaker units 32 are arranged in an arc shape when viewed from the side surface of the speaker device 3. Therefore, the directivity of the speaker device 3 in the arrangement direction is not sharper than that of the speaker device 1 having the same arrangement length L, and a desired sound field range can be obtained wider than that of the speaker device 1. FIG. 11 is a diagram showing the directivity of the speaker devices 1 and 3 having the same array length L in the arrangement direction, FIG. 11 (a) shows the directivity of the speaker device 3, and FIG. 11 (b) is a diagram. It shows the directivity of the speaker device 1. In FIG. 11, the radius of curvature R of the speaker device 3 is 3 [m], the array length L is 1.5 [m], and the array length L of the speaker device 1 is 1.5 [m]. Further, FIG. 11 shows the directivity when the frequency f is 1 [kHz] as an example. From the results of FIG. 11, it can be seen that the directivity of the speaker device 3 in the arrangement direction is not sharper than that of the speaker device 1 having the same arrangement length L, and a desired sound field range can be obtained wider than that of the speaker device 1. From the results of FIG. 11, the directivity of the speaker device 3 having the radius of curvature R of 3 [m] and the array length L of 1.5 [m] is the directivity of the speaker device 3 having the array length L of 3 [m]. It can also be seen that the sharpness is equal to or higher than. That is, when trying to obtain a desired sound field range in the arrangement direction, the arrangement length L of the speaker device 3 can be made shorter than that of the speaker device 1, and as a result, the device size is made smaller than that of the speaker device 1. be able to.

As described above, in the speaker device 3 according to the third embodiment, the speaker units 32 are arranged in an arc shape when viewed from the side surface of the speaker device 3, so that the sound field is more desired than that of the speaker device 1 in the arrangement direction. It can be seen that a wide range can be obtained. Therefore, the size of the speaker device 3 can be made smaller than that of the speaker device 1 while ensuring a sound field range equivalent to the sound field range in the arrangement direction of the speaker device 1 having a long array length.

When the speaker units 32 are arranged in an arc shape when viewed from the side surface of the speaker device 3, the directivity in the arrangement direction becomes sharper as the ratio of the wavelength of the reproduced sound to the arrangement length approaches a predetermined value. For example, when the arrangement length is fixed, the directivity becomes sharper as the wavelength of the reproduced sound becomes shorter, but conversely, the directivity becomes sharper when the wavelength of the reproduced sound becomes shorter than a predetermined wavelength. As shown in FIG. 12, in the speaker device 3 having an array length of 1 [m] to 2 [m], which is supposed to be used for home use, the frequency band where the directivity in the array direction is the sharpest is 250 [Hz. ] ~ 2 [kHz]. FIG. 12 is a diagram showing the directivity of the speaker device 3 in the arrangement direction for each frequency. In FIG. 12, as an example, the array length L is 1.5 [m] and the radius of curvature R is 2 [m]. In addition, the result shown in FIG. 12 shows the listening position P as shown in FIG.₁It is standardized with the sound pressure in. Therefore, the array length L and the radius of curvature R may be set so that a desired sound field range can be obtained in the frequency band where the directivity in the array direction is the sharpest. As a result, a sufficient listening area can be secured in the entire playback band. For example, in the frequency band 250 [Hz] to 2 [kHz] where the directivity in the arrangement direction is the sharpest, the sound pressure difference is measured at the listening position within the range of the elevation angle ± 15 [°] seen from the center of the arrangement of the speaker unit 32. When it is 6 [dB] or less, the array length L and the radius of curvature R may satisfy the condition of Eq. (4). In equation (4), the listening distance from the center of the arrangement of the speaker units 32 to the listening position is D (1 [m] to 3 [m]).

<maths num="4"><img file="JP5145334B2_D0004.tif" /></maths>

FIG. 14 is a diagram showing the contents of the equation (4). In FIG. 14, the center P of the arrangement of the speaker unit 32₀Is the origin on the Y axis, and the arrangement of the speaker units 32 is H.₁And the array length (length of the arc) is L. Listening position P₁Is the listening position when the elevation angle is 0 [°], and is the center P.₀Located on the X-axis through. Listening position P₁And center P₀Let D be the listening distance between them, and let R be the radius of curvature of the arc. Also, the listening position when the elevation angle is +15 [°] is P.₂And the listening position when the elevation angle is -15 [°] is P.₃And. At this time, the right side of equation (4) is the listening position P.₁~ P₃Array H passing through₁Arc H similar to₂Will be the length of. If the right side of this equation (4) is greater than or equal to the listening distance D, the listening position is the listening position P.₂Listening position P from₃Regardless of the position between, the sound pressure difference of the reproduced sound at the listening position is 6 [dB] or less. FIG. 15 shows the result of confirming by numerical calculation that the sound pressure difference is 6 [dB] or less. FIG. 15 (a) shows the numerical calculation results when the listening distance D is 2.5 [m] and the array length L is 1 [m], and FIG. 15 (b) shows the listening distance D of 2.5 [m], The numerical calculation result when the array length L is 1.25 [m] is shown, and Fig. 15 (c) shows the numerical calculation result when the listening distance D is 2.5 [m] and the array length L is 1.5 [m]. Shown. Note that FIG. 15 shows, as an example, the numerical calculation results at the listening position within the range of the elevation angle of 0 [°] to +15 [°]. From the results of FIGS. 15 (a) to 15 (c), when the value on the right side of equation (4) is greater than or equal to the listening distance D (= 2.5 [m]), the listening position is the listening position P.₁Listening position P from₂It can be seen that the sound pressure difference of the reproduced sound at the listening position is 6 [dB] or less at any position between the two.

In addition to the contents explained in FIGS. 12 to 15, when the listening distance D is 5 [m] or less, the result (L / R) obtained by dividing the array length L by the radius of curvature R is 1.5 or more. The array length L and the radius of curvature R may be set to. Even if the array length L and the radius of curvature R are set so that the result (L / R) obtained by dividing the array length L by the radius of curvature R is 0.5 or more when the listening distance D is 3 [m]. Good. FIG. 16 is a diagram showing the directivity of the speaker device 3 in the arrangement direction for each frequency when the listening distance D is 3 [m], and FIG. 16 (a) shows the division result (L / R). Fig. 16 (b) shows the directivity when the division result (L / R) is 1, and Fig. 16 (c) shows the directivity when the division result (L / R) is 1. The directivity when 0.75 is shown, and FIG. 16 (d) shows the directivity when the division result (L / R) is 0.5. From FIG. 16, when the listening distance D is 3 [m] and the division result (L / R) is 0.5 or more, the sharpness of the directivity in the arrangement direction becomes sharp enough to obtain a sufficient sound field range. Understand.

(Embodiment 4) Similar to the speaker device 1, the speaker device 3 according to the third embodiment has a limit in reducing the interval d due to its structure. Therefore, in the fourth embodiment, a speaker device capable of making the interval d smaller than that of the third embodiment and easily setting the interval de to a value satisfying the equation (2) will be described. Specifically, in the speaker device according to the fourth embodiment, the speaker unit is attached to the cabinet so that the adhesive margins of the adjacent edges overlap each other. Other structures and operations are the same as those of the speaker device 3, and description thereof will be omitted here.

FIG. 17 is a diagram showing the structure of the speaker device according to the fourth embodiment of the present invention, FIG. 17 (a) is a front view of the speaker device, and FIG. 17 (b) is a side view of the speaker device. It is a structural sectional view of.

The speaker device 4 includes a cabinet 41 and a plurality of speaker modules 42, and is installed in a place where the listening position is close, such as in a home. In the example of FIG. 17, the speaker device 4 includes, but is not limited to, five speaker modules 42. Each speaker module 42 contains four speaker units, respectively, and is mounted on the front of the cabinet 41. As shown in FIG. 17A, the speaker units are arranged in a straight line when viewed from the front of the speaker device 4, and the arrangement direction is parallel to the vertical direction of the speaker device 4. Further, as shown in FIG. 17B, the speaker units are arranged in an arc shape when viewed from the side surface of the speaker device 4. Note that FIG. 17B shows the structural cross section of the speaker module 42 in abbreviated form, and a detailed structural cross section is shown in FIG.

18A and 18B are views showing the structure of the speaker module 42, FIG. 18A is a front view of the speaker module 42, and FIG. 18B is a side structural sectional view of the speaker module 42. .. The speaker module 42 includes a frame 421 and four speaker units 32a. The frame 421 includes a front plate 4211, a support member 4212, and a connecting member 4213. The front plate 4211 and the support member 4212 are formed in an arc shape as shown in FIG. 18 (b). A connecting member 4213 for connecting the front plate 4211 and the support member 4212 is provided between the front plate 4211 and the support member 4212. The speaker unit 32a has a structure obtained by removing the frame from the speaker unit 32 shown in FIG. 7, and has an edge 322, a diaphragm 323, a voice coil bobbin 324, a voice coil 325, a yoke 326, a magnet 327, and a plate 328. .. The edge 322 includes a roll portion 3221 and an adhesive allowance 3222. The bonding allowance 3222 is bonded to the front plate 4211, and the inner circumference of the roll portion 3221 is bonded to the outer circumference of the diaphragm 323. As a result, the diaphragm 323 is oscillatedly supported by the front plate 4211. A part of the adjacent bonding allowance 3222 is bonded to the front plate 4211 in an overlapping manner as shown in the enlarged view surrounded by the dotted line in FIG. 18 (b). The inner circumference of the diaphragm 323 is adhered to one end of the voice coil bobbin 324 arranged in the through hole formed in the support member 4212. The voice coil 325 is wound around the voice coil bobbin 324. The yoke 326 is attached to the support member 4212 so as to surround the through hole formed in the support member 4212. One side of the magnet 327 is glued to the inner surface of the yoke 326 and the other side is glued to the plate 328. A magnetic gap is formed between the side surface of the plate 328 and the inner surface of the yoke 326, and the voice coil 325 is arranged in the magnetic gap. The dotted circle on the speaker unit 32a is the vibration region of the speaker unit 32a.

In the present embodiment configured as described above, as shown in FIG. 18A, the speaker units 32a are arranged so as to overlap each other's adhesion allowance 3222. As a result, the distance d between the vibration regions becomes smaller than the distance d in the case of the speaker device 3. Therefore, according to the present embodiment, the interval de can be easily set to a value satisfying the equation (2), and the deterioration of sound quality due to phase interference can be easily prevented.

Further, in the present embodiment, since the edge 322 exists between the diaphragms 323 of each speaker unit 32a, the diaphragms 323 vibrate independently of each other. Therefore, it is possible to prevent unnecessary resonance generated by the vibrations of the diaphragms 323 being transmitted to each other, and it is possible to vibrate all the speaker units 32a in the same phase.

In the above description, the speaker module 42 includes four speaker units 32a, but the present invention is not limited to this. For example, the speaker module 42 may include 20 speaker units 32a, and the speaker device 4 may include one speaker module 42.

Further, in the above description, each speaker unit 32a has an edge 322, but the present invention is not limited to this. Each edge 322 may be integrally molded with the adhesive allowance 3222 superimposed on each other, and one integrally molded edge may be shared by each speaker unit 32a.

Further, in the above, all of the speaker units 32a are arranged so as to overlap each other's adhesive allowance 3222, but only the two speaker units 32a are arranged so as to overlap each other's adhesive allowance 3222. May be good. Further, all of the speaker units 32a may be arranged so as not to overlap each other's adhesive margin 3222. Even in this case, each speaker unit 32a shares one frame 421. Therefore, the distance d between the vibration regions of each speaker unit 32a can be made smaller than that in the case where each speaker unit 32a includes a frame.

Further, in the above description, the speaker device 4 includes a plurality of speaker modules 42, but a plurality of speaker modules 22 shown in FIG. 6 may be provided. In this case, by arranging each speaker module 22 while tilting it by about 6 ° when viewed from the side surface of the speaker device 4, as shown in FIG. 17, the arrangement of the speaker units viewed from the side surface of the speaker device 4 is substantially circular. Can be arcuate.

Further, in the above description, the cabinet 41 is one of the components of the speaker device 4, but the cabinet 41 may be removed from the components of the speaker device 4. In this case, the speaker device 4 becomes the speaker module 42 itself.

Further, in the above description, the explanation is made on the premise that the distance difference Q satisfies the condition of the equation (2), but even if the equation (2) is not satisfied, the adhesive margins of the adjacent edges overlap each other, so that the adjacent edges are adjacent to each other. It is possible to suppress the deterioration of sound quality due to phase interference as compared with the case where the adhesive margins do not overlap each other.

(Embodiment 5) In the speaker device 3 according to the third embodiment, as shown in FIG. 7B, a plurality of speaker units 32 are arranged in an arc shape when viewed from the side surface of the speaker device 3. On the other hand, in the fifth embodiment, the arrangement shape seen from the side surface of the speaker device remains linear as in the first embodiment, and is the same as the case where the arc shape is formed as in the third embodiment. The case where the effect is obtained will be described.

FIG. 19 is a diagram showing the structure of the speaker device according to the fifth embodiment of the present invention, FIG. 19 (a) is a front view of the speaker device, and FIG. 19 (b) is a side view of the speaker device. It is a structural sectional view of. The speaker device 5 includes a cabinet 51, speaker units 52-1 to 52-20, and a delay means 53, and is installed in a place where the listening position is close, such as in a home. In the example of FIG. 19, the speaker device 5 includes 20 speaker units, but the present invention is not limited to this. The speaker units 52-1 to 52-20 are attached to the cabinet 51 so that the front surface faces the front direction of the cabinet 51. As shown in FIG. 19A, the speaker units 52-1 to 52-20 are arranged in a straight line when viewed from the front of the speaker device 5, and the arrangement direction is the vertical direction of the speaker device 5. It is parallel. Further, as shown in FIG. 19B, the speaker units 52-1 to 52-20 are arranged linearly when viewed from the side surface of the speaker device 5. The speaker units 52-1 to 52-20 have the same structural cross section as a normal electrodynamic speaker, and in FIG. 19B, the structural cross section of the speaker units 52-1 to 52-20 is shown. It is abbreviated. Since the method of arranging the speaker units 52-1 to 52-20 is the same as that of the first embodiment, the description thereof will be omitted here.

The delay means 53 has a delay time set corresponding to each of the speaker units 52-1 to 52-20, delays the input acoustic signal by the set delay time, and delays the delayed signal. Output to the speaker unit corresponding to the time. The delay time is from the arrangement position of the corresponding speaker unit to the arrangement position of the corresponding speaker unit when it is assumed that each speaker unit is arranged in an arc shape when viewed from the side surface of the speaker device. It is set to the time to transmit. Specifically, the delay means 53 includes delayers 53-1 to 53-9. Different delay times t1 to t9 are set for the delay devices 53-1 to 53-9. The specific setting method of the delay times t1 to t9 will be described later. The delay device 53-1 delays the input acoustic signal by the delay time t1 and outputs it to the speaker units 52-2 and 52-12. The delay device 53-2 delays the input acoustic signal by the delay time t2 and outputs it to the speaker units 52-3 and 52-13. Hereinafter, similarly, the delay devices 53-3 to 53-9 delay the acoustic signal by the set delay time and output it to the speaker units 52-4 to 52-10 and 52-14 to 52-20. Since the speaker units 52-1 and 52-11 are arranged near the center of the array, it is not necessary to delay the acoustic signal. Therefore, for the speaker units 52-1 and 52-11, the delay time is set to 0 and the acoustic signal is directly input. The method of setting the delay time will be described below. FIG. 20 is a diagram for explaining a method of setting the delay time. In FIG. 20, the center P of the arrangement of the speaker unit 52₀Is the origin on the Y axis, and the arrangement of the speaker units 52 is H.₃And let L be the array length (the length of the straight line). In addition, when each speaker unit 52 is virtually arranged in an arc shape, the arrangement is H'.₃And the array length (length of the arc) is L'. Point P_RIs the center of the arc whose radius of curvature is R, and the center P₀Located on the X-axis through. At this time, the relationship of Eq. (5) holds between the sequence length L and the sequence length L'.

<maths num="5"><img file="JP5145334B2_D0005.tif" /></maths>

Therefore, the array H₃From the top to the center P₀Distance y_maxIs expressed as in Eq. (6).

<maths num="6"><img file="JP5145334B2_D0006.tif" /></maths>

Also, the center P₀SA the effective vibration area of the speaker unit 52-1 located nearby₀And the effective vibration area is SA₀The nth effective vibration region counted in the positive direction of the Y-axis is SA_nAnd. Also, the effective vibration region SA_nCenter P from the top of₀Distance to y_nAnd effective vibration area SA_nCenter of A_nAnd. Where the array H'₃Top point A'_nThe sound waves radiated from the array H travel in the direction perpendicular to the tangent of the arc.₃Reach the upper point An. Point An-Point A'at this time_nDistance B between_nIs expressed as in Eq. (7).

<maths num="7"><img file="JP5145334B2_D0007.tif" /></maths>

Therefore, the effective vibration region SA_nDelay time t required to operate as if it were placed at point A'n_nIs expressed as in Eq. (8). Note that c in Eq. (8) is the speed of sound.

<maths num="8"><img file="JP5145334B2_D0008.tif" /></maths>

By setting the delay times t1 to t9 based on the equation (8), the speaker units 52-1 to 52-20 are arranged as if they were H'.₃It works as if it is arranged in an arc like. As described above, in the speaker device 5 according to the fifth embodiment, it is possible to perform the same operation as in the case where the arrangement shape of the speaker units viewed from the side surface of the speaker device is linear and arcuate. It is possible to obtain the same effect as when the arc shape is formed. In the above description, the acoustic signal input to the speaker units 52-1 to 52-20 is only delayed, but the present invention is not limited to this. The inclination of the speaker units 52-1 to 52-20 may be changed according to the arcuate arrangement. FIG. 21 is a diagram showing how the inclinations of the speaker units 52-1 to 52-20 are changed according to the arcuate arrangement. In FIG. 21, the effective vibration region SA is not shown in the speaker units 52-1 to 52-20 itself._nShows the slope of. In FIG. 21, the effective vibration region SA_nThe slope of is θ with respect to the y-axis_nAnd. At this time, the slope θ_nIs expressed as in Eq. (9).

<maths num="9"><img file="JP5145334B2_D0009.tif" /></maths>

By changing the inclination of the speaker units 52-1 to 52-20 so as to satisfy the equation (9), better radiation characteristics can be obtained in the arrangement direction of the speaker units 52-1 to 52-20. In the above description, the case where the delay devices 53-1 to 53-9 are applied to the first embodiment has been described, but the delay devices 53-1 to 53-9 can also be applied to the second embodiment. Further, in the above description, the delay means 53 is a part of the component of the speaker device 5, but the present invention is not limited to this. The delay means 53 may be provided in an audio amplifier (not shown) connected to the speaker device 5. Further, the delay means 53 may be composed of either an analog circuit or a digital circuit.

(Embodiment 6) In the present embodiment, a case where the speaker devices according to the first to fifth embodiments are mounted on a video device such as a flat-screen television will be described. FIG. 22 is a front view of the flat-screen television according to the sixth embodiment. The flat-screen television 6 includes a housing 61, a display 62, and a speaker device 63. The housing 61 has a shape in which the thickness in the front-rear direction gradually decreases from the central portion toward both ends in the left-right direction. The display 62 is mounted in the central portion of the housing 61, and the speaker device 63 is mounted inside the housing 61 at both ends in the left-right direction.

FIG. 23 is a diagram showing the structure of the speaker device 63, FIG. 23 (a) is a front view of the speaker device 63, and FIG. 23 (b) shows the speaker device 63 cut along the line C-C'. It is a structural cross-sectional view of the time. As shown in FIG. 23, the speaker device 63 includes a frame 631 and a plurality of speaker units 632. The speaker unit 632 is a piezoelectric speaker, and includes a substrate 6321, a piezoelectric element 6322, edges 6323a, and 6323 b. As shown in FIG. 23 (b), the piezoelectric elements 6322 are provided on the upper and lower surfaces of the substrate 6321, respectively. As shown in FIG. 23A, the edges 6323a are provided at the upper and lower ends of the substrate 6321 and the piezoelectric element 6322, respectively, and the edges 6323b are provided at the left and right ends of the substrate 6321 and the piezoelectric element 6322, respectively. As shown in FIG. 23A, the piezoelectric element 6322 has a rectangular shape and is connected to an electrode formed on the frame 631 and the damper portion 631a of the frame 631. When an acoustic signal is input through the electrodes, the piezoelectric element 6322 vibrates together with the substrate 6321 to convert the acoustic signal into sound waves.

Here, the vibration region of the speaker unit 632 has the shape of the piezoelectric element 6322, that is, a rectangle. Therefore, the vibration region of the speaker unit 632 becomes the effective vibration region itself, and the interval between the vibration regions of the adjacent speaker units 632 is the interval de of the effective vibration region. Here, it is assumed that the distance de is set so that the distance difference Q satisfies the condition of the equation (2).

In the speaker device 63 configured as described above, a plurality of speaker units 632 share one frame 631. Therefore, the interval de of the effective vibration regions of the adjacent speaker units 632 can be made smaller than that in the case where each of the plurality of speaker units 632 includes a frame. Further, since the speaker unit 632 is a piezoelectric speaker, the size of the entire speaker device 63 can be reduced. Further, in the speaker device 63, the frame 631, the substrate 6321, the edges 6323a and 6323b can be integrally molded. Therefore, the manufacturing cost can be reduced as compared with the case where the plurality of speaker units 632 are separately attached.

The structure of the speaker device 63 is not limited to the structure shown in FIG. 23, and may be a structure that shares the edges of adjacent speaker units as shown in FIG. 24. FIG. 24 is a diagram showing another structure of the speaker device 63, FIG. 24 (a) is a front view of the speaker device 63, and FIG. 24 (b) is a line C-C'of the speaker device 63. It is a structural sectional view at the time of cutting. As shown in FIG. 24, the speaker device 63 includes a frame 631 and a plurality of speaker units 632a. The speaker unit 632a is a piezoelectric speaker, and includes a substrate 6321, a piezoelectric element 6322, edges 6323c, and 6323d. As shown in FIG. 24A, the edges 6323c are provided at the upper and lower ends of the substrate 6321 and the piezoelectric element 6322, respectively, and the edges 6323d are provided at the left and right ends of the substrate 6321 and the piezoelectric element 6322, respectively. The edge 6323c is shared between adjacent speaker units 632a.

Here, the interval de of the effective vibration region of the speaker unit 632a is the width of the edge 6323c. According to the structure shown in FIG. 24, the interval de of the effective vibration region of the speaker unit can be made smaller than the interval de shown in FIG. 23.

The speaker device according to the present invention can suppress sound quality deterioration due to phase interference when used in a place where the listening position is a short distance, and is small for a home audio system, a home theater system, a loudspeaker system for a small hall, or the like. It is applied to music playback systems of sound fields.

1,2,3,4,5,63,9 speaker device 11, 21, 31, 41, 51, 91 cabinets 12, 12a, 32, 32a, 52-1 ~ 52-20, 632, 632a, 92 speaker unit 121, 221, 421, 631 frames 122, 322, 6323a ~ d edge 123, 323 diaphragm 124, 324 Voice coil bobbin 125, 325 voice coil 126, 326 York 127, 327 magnets 128, 328 plates 1221, 3221 Roll part 1222, 3222 Adhesion allowance 22, 42 speaker module 2211, 4211 Front plate 2212, 4212 Support members 2213, 4213 Connecting member 53 Delay means 53-1 ~ 53-9 Delayer 6 Flat-screen TV 61 housing 62 display 631a Damper section 6321 board 6322 Piezoelectric element