JP4226453B2 - Sound playback device - Google Patents

Description

  The present invention relates to a sound reproducing device that vibrates a sounding member such as a transparent panel of a display unit or a housing of an electronic device, and particularly relates to a sound reproducing device that can increase sound generation in a wide band.

  A panel-type sound reproducing device that vibrates a panel to generate sound is described, for example, in Patent Document 1 below.

In the device described in Patent Document 1, a small panel having an area smaller than that of the large panel is placed on top of the large panel, and driving means is attached to the small panel. In this sound reproducing apparatus, when the driving means is driven, the small panel vibrates, the vibration of the small panel is transmitted to the large panel, and a large-band output is obtained by generating sound from the large panel and the small panel. That's it.
JP-T-2002-505814

  However, since the large panel has a relatively high band with high rigidity and a resonance frequency of 1 kHz or more, the amplitude of the large panel can be ensured for a low frequency range of several hundred Hz even if the volume can be secured in a high frequency range. Cannot be increased, and sufficient volume cannot be obtained. Therefore, when a large panel is used for sound generation, a high sound range becomes dominant, and it is difficult to obtain sound quality like a general speaker.

  In particular, in the case where the driving means is provided at a position close to the side edge rather than the central portion of the large panel, when the periphery of the large panel is fixed, the portion where the driving means is provided Since the resonance frequency of the panel is high, it is difficult to increase the volume of the bass.

  Also, if the large panel is made thin and soft, it cannot be placed on the surface of the device because it is too soft, and the vibration propagation characteristics are poor, so that it is impossible to ensure a large volume.

  The present invention solves the above-described conventional problems, and can be mounted on a sound generating member such as a transparent panel provided in a display means or a casing of an electronic device to output a high volume over a wide band from high to low. An object is to provide a sound reproducing device.

The present invention includes a panel which is sound-producing member, the sound reproducing apparatus and a vibration generating device which sound is provided by applying vibration to the panel,
The vibration generating means includes a vibration plate, a support member connected to the vibration plate at at least two connecting portions, a coil provided on one of the vibration plate and the support member, and the coil provided on the other side. Magnetic field generating means for applying a magnetic field to
A transmission member having an area smaller than that of the diaphragm is joined to the diaphragm, and the transmission member is attached to the panel directly or via another member, and the connection between the diaphragm and the support member The portion is provided without being fixed to the panel at a position deviated from the joint portion between the transmission member and the diaphragm .

Since the vibration generating means of the sound reproducing apparatus of the present invention is in a substantially free state except for the connecting portion with the sounding member that is a panel , the vibration generating means vibrates with a large amplitude. The sound generating member is forcibly vibrated by the vibration of the vibration generating means, and a sound with a large volume can be obtained from the sound generating member. Further, since the vibration generating means vibrates with a large amplitude even in a low frequency band and the vibration acts on the sound producing member, it is possible to obtain a louder sound volume than before even in a low sound range.

The present invention, the diaphragm and the support member, in the longitudinal direction of the larger elongated than the width of the linear dimension transversely shape, the consolidated portion of the two portions apart open-digits in the longitudinal direction of the diaphragm It is preferable that the diaphragm and the support member are connected, and an intermediate portion of the two connecting portions is joined to the transmission member .

  In the above configuration, since the diaphragm can vibrate with a large amplitude in the vertical direction, a large amplitude can be given to the sound producing member.

The present invention, said vibration generating means is arranged in the vicinity of the side edges of the panel, the diaphragm is arranged in parallel with the side edge portion, the peripheral portion of the panel via a damper Is supported by the housing.

  As described above, even when the vibration generating device is arranged in the vicinity of the side edge of the panel, it is possible to obtain a large volume of sound in a wide frequency band from the panel, and the central portion of the panel can be effectively used as a display screen or the like. .

In the present invention, it is preferable that the transmission member is formed of a synthetic resin material .

  When the transmission member is provided, the diaphragm and the support member vibrate with a large amplitude without being constrained by the sound generation member, and the amplitude is efficiently transmitted to the sound generation member via the transmission member. Become.

  In the present invention, it is preferable that the bending rigidity of the diaphragm is lower than the bending rigidity of the support member.

  In this configuration, both the diaphragm and the support member vibrate in the vibration generating means, but the amplitude of the diaphragm can be set large, and it is easy to give a large amplitude from the diaphragm to the sounding member.

  Further, instead of the coil and the magnetic field generating means, a piezoelectric vibrator fixed to the diaphragm may be provided.

  According to the present invention, since the vibration plate can be vibrated greatly at a low resonance frequency and this vibration can be transmitted to the sound producing member, not only high frequency sound but also low frequency sound can be output from the sound producing member with a large volume.

  1 is a plan view of an electronic apparatus equipped with a sound reproducing device according to an embodiment of the present invention as viewed from the sound generation side, FIG. 2 is an exploded perspective view of the sound reproducing device, and FIG. 3 is a line 3-3 in FIG. FIG. 4 is a sectional view taken along line 4-4 of FIG. 1, and FIG. 5 is a graph showing a comparison of frequency band characteristics between the present embodiment and the conventional embodiment.

  FIG. 1 shows an electronic device 10 on which a sound reproducing device of the present invention is mounted, and a transparent panel 20 is provided on the front surface of a housing 21. In this embodiment, the panel 20 functions as a sounding member. On the back side of the panel 20, the sound reproducing devices 1 and 1 are arranged inside the left and right side edges of the panel. An intermediate portion between the left and right sound reproducing apparatuses 1 and 1 is a display see-through region, and an FPD (flat display unit) 30 having a shape indicated by a two-dot chain line in FIG.

  Both the sound reproducing device 1 and the sound reproducing device 1 located on both the left and right sides have the same configuration. In the following description, the X direction is the horizontal direction and the Y direction is the vertical direction. The panel 20 has a rectangular shape in which the horizontal dimension is longer than the vertical dimension.

  As shown in FIG. 2, the sound reproducing device 1 has vibration generating means 3. The vibration generating means 3 is arranged in parallel with the side edges of the panel 20 in the vicinity of both side edges of the panel 20.

  The vibration generating means 3 is configured by connecting a diaphragm 2 and a support member 5. The diaphragm 2 has an elongated thin plate shape in which the length dimension in the vertical direction (Y direction) is sufficiently larger than the width dimension in the horizontal direction (X direction). The diaphragm 2 is formed of a synthetic resin plate material such as polycarbonate, acrylic, or polyethylene terephthalate (PET).

  The support member 5 is formed of a magnetic material such as a steel plate, and is formed with connecting portions 5a and 5a bent in an L shape at both ends in the vertical direction, and on both side portions extending in the vertical direction. Bent portions 5b and 5b are formed. The vertical dimension of the support member 5 and the vertical dimension of the diaphragm 2 are formed substantially the same, and the connecting portions 5 a and 5 a of the support member 5 are attached to both ends of the diaphragm 2 with an adhesive or the like. It is fixed with. As shown in FIGS. 3 and 4, the bent portions 5 b and 5 b of the support member 5 are set to dimensions that do not contact the diaphragm 2.

  The bending rigidity of the diaphragm 2 is sufficiently smaller than the bending rigidity of the support member 5. The resonance frequency of the diaphragm 2 is sufficiently smaller than the resonance frequency of the panel 20, for example, the resonance frequency of the panel 20 is 1 kHz or more and 3 kHz or less, and the resonance frequency of the diaphragm 2 is 200 Hz or more and 600 Hz or less. .

  As shown in FIG. 3, a magnet M formed of a permanent magnet such as ferrite or rare earth as a magnetic field generating means is fixed to the support member 5 at the bottom 5c facing the diaphragm 2. The magnet M has an elongated shape in the vertical direction and is fixed to the central portion of the support member 5 in the vertical direction. A yoke 6 made of a magnetic material is overlapped and fixed to the magnet M. The yoke 6 is formed in the same area as the upper surface of the magnet M, and has a thickness that prevents the yoke 6 from contacting the diaphragm 2 when the yoke 6 and the magnet M overlap each other.

On the other hand, the diaphragm 2 is provided with a coil C on the side facing the support member 5. The coil C is wound in a rectangular frame shape with a coated copper wire or the like and is elongated in the vertical direction. The coil C is fixed to the central portion in the vertical direction of the diaphragm 2 with an adhesive or the like. The coil C has a pair of longitudinal current path Ca longitudinally extending, and C a, a pair of laterally extending lateral current path Cb, and Cb.

  When the support member 5 is fixed to the diaphragm 2, the magnet M and the yoke 6 are inserted so as to be positioned in the coil C. At this time, gaps G and G having minute intervals are formed between the bent portions 5b and 5b of the support member 5 and the magnet M and the yoke 6, and the longitudinal current of the coil C is formed in the gaps G and G. Roads Ca and Ca are located. That is, the bent portions 5b and 5b function as opposing yokes.

  As shown in FIG. 3, when the Z1 side of the magnet M is magnetized to the N pole and the Z2 side is magnetized to the S pole, the magnet M, the yoke 6, the gap G, the bent part 5b and the bottom part 5c of the support member 5 are used. A magnetic path through is formed. Therefore, as shown in FIG. 3, by energizing the longitudinal current path Ca on the X1 side of the coil C toward the back side of the paper, a current in the opposite direction to the longitudinal current path Ca on the opposite X2 side is supplied. In this case, a force that bends and deforms in the Z2 direction acts on the support member 5. In addition, by energizing in the direction opposite to the above, a force to bend and deform in the Z1 direction acts on the support member 5. Thus, by vibrating the support member 5 in the Z1-Z2 direction, the diaphragm 2 also vibrates in the Z1-Z2 direction at the same time.

  The vibration generating means 3 is not only a driving means using magnetism, but also a piezoelectric vibrator is provided between the diaphragm 2 and the support member 5, and this piezoelectric vibrator is the diaphragm 2 and the support member 5. The vibration plate 2 may be deformed by vibration. Further, a magnet and a yoke may be provided on the diaphragm 2 side, and a coil may be provided on the support member 5 side.

  Further, a pair of upright pieces are formed on the bottom 5c of the support member 5, and the upright pieces are arranged so as to be located outside the lateral current paths Cb and Cb of the coil C, and the upright pieces and A magnetic path may be formed by the yoke 6, the magnet M, and the bottom portion 5c.

  When the coil C is energized, the vibration generating means 3 of this embodiment is such that a vibration force acts on both the diaphragm 2 and the support member 5 so that the diaphragm 2 and the support member 5 approach each other. They vibrate away from each other. That is, the vibration generating means 3 has a single excitation function. Since the vibration plate 2 has low bending rigidity and both ends extending in the vertical direction are connected to the connection portions 5a and 5a of the support member 5, the vibration plate 2 uses the fixed portions at the connection portions 5a and 5a as simple support portions. Oscillate with its center bent. The support member 5 also vibrates, but its amplitude is sufficiently smaller than the amplitude of the diaphragm 2.

  In the vibration generating means 3, a part of the diaphragm 2 is indirectly supported by the panel 20. That is, the diaphragm 2 is supported by the panel 20 through the transmission member 4 at an intermediate portion between the connecting portion 5a and the connecting portion 5a.

  As shown in FIG. 2, the diaphragm 2 has a long shape in which the length dimension in the vertical direction (Y direction) is longer than the width dimension in the horizontal direction (X direction), and the Z direction of the diaphragm 2. This is a shape having an area sufficiently smaller than the vibration surface 2a facing the surface. That is, the transmission member 4 is formed such that the vertical dimension is longer than the vertical dimension of the magnet M and the yoke 6, and the horizontal dimension is shorter than the width dimension of the diaphragm 2. The diaphragm 2 is fixed to the central portion in the longitudinal direction with an adhesive or the like. Thus, the transmission member 4 is fixed to a part of the vibration surface 2a of the diaphragm 2, and the non-connection portion 2b where the transmission member 4 is not fixed to both sides of the transmission member 4 in the Y direction. , 2b are formed.

  The transmission member 4 is made of a synthetic resin material such as polycarbonate, acrylic, or PET.

In the sound reproducing device 1 of the present embodiment, an air layer Q is provided between the transmission member 4 and the panel 20. The air layer Q is composed of a plate material 8a and a spacer 8b. The plate member 8a is made of synthetic resin, is longer than the vertical dimension of the transmission member 4 and shorter than the vertical dimension of the diaphragm 2, and the vertical center portion of the transmission member 4 and the plate member 8a. Are overlapped and fixed so as to coincide with the central portion in the vertical direction. The spacer 8b is an adhesive layer formed of a double-sided tape or the like having a certain thickness, is formed in a square frame shape, and is fixed to the entire periphery of the plate member 8a. The other surface of the spacer 8 b is fixed to the surface of the panel 20. Thereby, the said air layer Q sealed is formed between the panel 20 and the board | plate material 8a.
The diaphragm 2 is bonded and fixed to the plate member 8a through the transmission member 4.

  In the present embodiment, the structure in which the air layer Q is provided is illustrated and described. However, the transmission member 4 is directly fixed to the panel 20 without providing the air layer Q composed of the plate material 8a and the spacer 8b. But you can.

  Moreover, although the said diaphragm 2 and the said transmission member 4 are formed with a separate member, the said diaphragm 2 and the transmission member 4 may be formed integrally.

As shown in FIG. 1, the sound reproducing apparatus 1 of the present embodiment is arranged in the same manner at the edge of the panel 20 on the short side in the X1 direction. The panel 20 is provided in an opening 23 formed in the casing 21 formed by a bottom plate 21a and a side plate 21b as shown in FIGS. The side plate 21b of the casing 21 and supporting portion 21c projecting inward direction is formed on the entire inner wall, the damper 22 along the supporting portion 21c is fixed, the peripheral edge of the panel 20 in the dampers 22 The part is elastically supported.

Next, the operation of the sound reproducing device 1 of the present invention will be described.
In this sound reproducing apparatus 1, when the coil C is energized based on an audio signal or a music signal, the vibration generating means 3 generates self-vibration in the Z1-Z2 direction by the magnetic driving force. Is vibrated in the Z1-Z2 direction. Since only the central part of the diaphragm 2 is partially fixed to the panel 20, the vibration generating means 3 is not connected to the panel 20 by the unconnected portions 2 b and 2 b at both ends in the Y direction of the diaphragm 2. Is amplified by the vibration operation of the support member 5, and the diaphragm 2 is vibrated with a large amplitude. Further, since the diaphragm 2 is fixed to the plate member 8a through the synthetic resin transmission member 4, the vibration of the diaphragm 2 is not excessively restrained. Further, the amplitude of the diaphragm 2 is reliably transmitted to the plate member 8 a and the panel 20 through the transmission member 4.

  As described above, the vibration generating means 3 is in a free state except for the bonding portion with the transmission member 4, and the support member 5 and the diaphragm 2 vibrate freely by energization of the coil C, and the diaphragm 2 is particularly large. Operates with amplitude. Due to the amplitude of the diaphragm 2, the panel 20 is forcibly vibrated through the plate member 8 a, so that the amplitude of the panel 20 increases and the volume of sound produced from the panel 20 increases.

  Since the resonance frequency of the diaphragm 2 is low, the amplitude of the diaphragm 2 is increased even in a low sound range. By transmitting this amplitude to the panel 20, the panel 20 can exhibit a large volume in a low sound range.

  As described above, the vibration in the low frequency region generated by the diaphragm 2 is transmitted to the panel 20 via the transmission member 4, and a low frequency, that is, a low frequency part of voice or music is clearly output from the panel 20. Become so. In addition, since the vibration is amplified at both ends of the diaphragm 2 and is vibrated with a large amplitude, a bass having a larger sound pressure can be output. Further, stereo sound can be generated by the left and right sound reproducing apparatuses 1 and 1.

  FIG. 5 is a graph comparing the comparative example and the above-described embodiment in terms of the relationship between frequency (hertz) and sound pressure level (decibel). In FIG. 5, a graph indicated by a dotted line is a comparative example, and a graph indicated by a solid line is the present embodiment.

  In the comparative example, the coil C is directly fixed to the panel 20 without providing the plate material 8 a and the diaphragm 2, and the connecting portions 5 a and 5 a of the support member 5 having the magnet M and the yoke 6 are fixed to the panel 20. .

  As shown in FIG. 5, in the comparative example, the sound pressure is drastically lowered in a low frequency band of less than 1 kHz, but this is directly driven by vibration with respect to the panel 20 by the magnetism generating means by the coil C and the magnet M. This is because the panel 20 having a high resonance frequency cannot vibrate with a large amplitude in a low frequency band because a force is applied.

  On the other hand, in the embodiment of the present invention, the sound pressure is not greatly reduced even in a low frequency region lower than 1 kHz, and a sufficient sound pressure output can be obtained.

  In the present embodiment, since the air layer Q formed of the plate material 8a and the spacer 8b is formed between the transmission member 4 and the panel 20, it is possible to prevent a decrease in output of sound pressure in the high frequency region. It has become.

  In the sound reproducing device 1 according to the present invention, the panel 20 is made transparent, and an FPD formed of liquid crystal or the like is arranged in the center of the panel 20, so that the sound reproducing device 1 is arranged based on the screen displayed on the FPD. The sound may be generated from the panel 20 by driving.

  Further, the sound generating member on which the sound reproducing device 1 is mounted is not limited to the panel 20 described above, and a vibrable member disposed inside the casing of the electronic device or the casing of the electronic device itself. Can be used as a sounding member.

  Further, the panel 20, the diaphragm 2, and the transmission member 4 are not limited to the same material, but can be configured by combining different materials, and the frequency characteristics can be varied by changing these combinations. For example, the diaphragm 2 can be formed of a metal plate.

The top view which shows the electronic device by which the sound reproduction apparatus of embodiment of this invention is mounted, An exploded perspective view of the sound reproducing device, FIG. 3 is a sectional view taken along line 3-3 in FIG. FIG. 4 is a cross-sectional view taken along line 4-4 of FIG. A graph showing the characteristics of the frequency band,

Explanation of symbols

C Coil M Magnet 1 Sound reproduction device 2 Diaphragm 2a Vibration surface 3 Vibration generating means 4 Transmission member 5 Support member 5a Connection portion 5b Bending portion 6 Yoke 10 Electronic device 20 Panel 21 Housing 22 Damper 30 FPD

Claims (7)

In a sound reproducing device provided with a panel that is a sound generating member and vibration generating means for generating vibration by giving vibration to the panel ,
The vibration generating means includes a vibration plate, a support member connected to the vibration plate at at least two connecting portions, a coil provided on one of the vibration plate and the support member, and the coil provided on the other side. Magnetic field generating means for applying a magnetic field to
A transmission member having an area smaller than that of the diaphragm is joined to the diaphragm, and the transmission member is attached to the panel directly or via another member, and the connection between the diaphragm and the support member The sound reproducing device is characterized in that the portion is provided without being fixed to the panel at a position deviated from a joint portion between the transmission member and the diaphragm . Said diaphragm and said support member in the longitudinal direction of the larger elongated than the width of the linear dimension transversely shape, the said diaphragm at the junction of the two portions apart open-digits in the longitudinal direction of the diaphragm The sound reproducing device according to claim 1 , wherein a support member is connected, and intermediate portions of the two connecting portions are joined to the transmission member . The vibration generating means is arranged in the vicinity of the side edge of the panel, the diaphragm is arranged so as to be parallel to the side edge, and the peripheral edge of the panel is supported by the casing via a damper. sound reproducing apparatus of which claim 1 or 2 wherein the. The sound reproducing device according to claim 1, wherein the transmission member is formed of a synthetic resin material .   The sound reproducing device according to claim 1, wherein the bending rigidity of the diaphragm is lower than the bending rigidity of the support member. Alternatively, an audio reproducing device according to any one of claims 1 to 5 fixed piezoelectric vibrator to the vibration plate is provided in the coil and the magnetic field generating means. A plate material having a larger area than the transmission member is provided between the panel and the transmission member, the transmission member is fixed to a central portion of the plate material, and an outer peripheral portion of the plate material is interposed via a spacer. The sound reproducing device according to claim 1, which is fixed to a panel .

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