JP2014127844A - Acoustic generator, acoustic generating device, and electronic apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an acoustic generator which attains good sound pressure frequency characteristics, and to provide an acoustic generating device and an electronic apparatus.SOLUTION: An acoustic generator includes: an exciter 5 which has an external electrode 7 and is vibrated by an electric signal; a vibrating body 3 to which the exciter 5 is attached, and which is vibrated with the exciter 5 by vibrations of the exciter 5; and a wiring member 9 which is connected with the external electrode 7 provided at the exciter 5 and inputs the electric signal to the exciter 5. The wiring member 9 has a metal wire member 9a formed into one of a coil shape, a strand wire shape, and a net shape.

Description

  Embodiments of the disclosure relate to a sound generator, a sound generation device, and an electronic apparatus.

  Conventionally, an acoustic generator using an actuator is known. For example, Patent Document 1 describes a sound generator that outputs a sound by vibrating a diaphragm by applying a voltage to a piezoelectric element attached to the diaphragm and causing it to vibrate.

  In the acoustic generator described in Patent Document 1, a lead wire is soldered to the piezoelectric element, and a voltage is applied to the piezoelectric element through the lead wire, and the piezoelectric element is connected to the piezoelectric element. The lead wire has a structure in which the lead wire is once fixed to a frame member on the outer peripheral side of the sound generator and connected to the power supply device.

Japanese Patent Laid-Open No. 2004-23436

  However, in a structure such as that found in the acoustic generator described in Patent Document 1, the lead wire vibrates due to the vibration of the diaphragm, and the vibration of the lead wire causes a peak in the frequency characteristic of sound pressure (sound pressure more than the surroundings). ) And dip (parts where the sound pressure is lower than the surroundings) are likely to occur, and it is difficult to obtain good sound quality.

  Accordingly, the present invention has been made in view of the above, and an object of the present invention is to provide an acoustic generator, an acoustic generator, and an electronic apparatus that can obtain a favorable frequency characteristic of sound pressure.

  An acoustic generator according to an aspect of an embodiment has an external electrode, and is provided with an exciter that vibrates by an electric signal, and the vibrator that is attached to the exciter and vibrates with the exciter due to vibration of the exciter And a wiring member that is connected to the external electrode provided in the exciter and inputs an electrical signal to the exciter, and the wiring member is wound, twisted, and mesh-shaped It has the metal wire formed in the shape in any one of these, It is characterized by the above-mentioned.

  According to one aspect of the embodiment, a favorable sound pressure frequency characteristic can be obtained.

(A) is a top view which shows typically the structure of the sound generator of 1st Embodiment, (b) is the sectional view on the AA 'line of (a), (c) is (b). It is BB 'sectional drawing. It is a schematic diagram of the metal wire which comprises a wiring member, (a) is winding shape, (b) is stranded wire shape, (c) is mesh shape. (A) is a top view which shows typically the structure of the sound generator of 2nd Embodiment, (b) is the B-B 'sectional view taken on the line of (a). (A) is a top view which shows typically the structure of the sound generator of 3rd Embodiment, (b) is the B-B 'sectional view taken on the line of (a). (A) is a top view which shows typically the structure of one Embodiment of the conventional acoustic generator, (b) is the sectional view on the AA 'line of (a), (c) is (b). It is BB 'sectional drawing of.

  Hereinafter, embodiments of a sound generator, a sound generator, and an electronic device disclosed in the present application will be described in detail with reference to the accompanying drawings. In addition, this invention is not limited by embodiment shown below.

  First, the structure of the sound generator 1 of this embodiment is demonstrated using FIG. 1 (a) (b) (c) and FIG. Fig.1 (a) is a top view which shows typically the structure of the sound generator of 1st Embodiment, FIG.1 (b) is the sectional view on the AA 'line of (a), FIG.1 (c). ) Is a sectional view taken along the line BB 'in FIG. FIG. 2 is a schematic view of a metal wire constituting the wiring member, in which (a) is a winding shape, (b) is a stranded wire shape, and (c) is a mesh shape. Here, in FIG. 2, the cylindrical body shown inside the metal wire is shown for convenience in order to show a winding-like and mesh-like structure, and does not show that it has a cylindrical body. Absent.

  For ease of explanation, FIGS. 1A, 1B, and 1C illustrate a three-dimensional orthogonal coordinate system including a Z-axis in which a vertical upward direction is a positive direction and a vertical downward direction is a negative direction. Show. Such an orthogonal coordinate system may also be shown in other drawings used in the following description. Similarly, for easy understanding, FIGS. 1B and 1C show the sound generator greatly exaggerated in the thickness direction (Z-axis direction).

  As shown in FIG. 1A, in the sound generator according to the present embodiment, a film to be a vibrating body 3 is attached to a frame body 1 having a center region opened in a quadrilateral shape. An exciter 5 that vibrates in response to an electric signal is provided on one main surface side.

  Specifically, for example, a piezoelectric element as shown in FIG. 1B is bonded to the upper surface of a film-like vibrating body 3 serving as a support plate held by the frame body 1. Here, an external electrode 7 for supplying power from the outside is provided on the surface of the exciter 5. In addition, a wiring member 9 for inputting an electric signal to the exciter is connected to the external electrode 7 provided in the exciter 5, and subsequently, the wiring member 9 is fixed to the frame body 1. Here, the wiring member 9 is formed of a metal wire 9a formed in any one of a winding shape, a stranded wire shape, and a mesh shape as shown in FIG.

  For example, taking the conventional sound generator shown in FIGS. 5A, 5B, and 5C as an example, the wiring constituted by a single wire metal wire fixed on the exciter 105 and the frame body 101. The member 109 is normally induced to vibrate in the vibrating body 103 with the excitation of the piezoelectric element which is the exciter 105, but the frame body 101 vibrates simultaneously with the vibrating body 103.

  At this time, the wiring member 109 is substantially linear so as to bridge between the exciter 105 and the frame member 101 (the wiring member 109 is substantially parallel to the surface of the vibrating body 103 between the exciter 105 and the frame 101). It is provided to become. When the wiring member 109 is linear as described above, the wiring member 109 is usually tensioned between the exciter 105 and the vibrating body 103 and the frame body 101, and the vibration of the exciter 105 is restrained. It becomes easy to be done.

  As a result, the exciter 105 has a difference in the amplitude of vibration between the direction of the wiring conductor 109 and the other direction, and the vibrating body 103 sometimes has a place where the amplitude of vibration is large and small. Since the distribution is likely to occur, the sound pressure is likely to be partially amplified, and thus a large peak dip is likely to occur in the frequency characteristics of the sound pressure.

On the other hand, in the acoustic generator of the first embodiment, as shown in FIG. 2, the wiring member 9 installed between the external electrode 7 provided on the exciter 5 and the frame 1 is straight at first glance. Even if the wiring member 9 itself has a shape, the wiring member 9 itself has a structure such as a winding shape, a stranded wire shape, and a mesh shape in which the shape can be changed by changing the shape. For this reason, tension is hardly generated in the wiring member 9 between the external electrode 7 of the exciter 5 and the frame 1, and thereby the restraint of the wiring member 9 on the vibration of the exciter 5 can be weakened.

  As a result, the exciter 5 has a small difference in amplitude of vibration between the direction of the wiring member 9 and the other direction, and partial sound pressure amplification in the vibrating body 3 is reduced. Thus, the peak dip in the frequency characteristic of the sound pressure can be reduced, and the sound pressure can be stabilized.

  In this case, the shape of the wiring member 9 is desirably a mesh shape in that the restraining force due to the tension can be reduced and the shape retainability can be further improved.

  The metal wire constituting the wiring member 9 can be applied to any metal material that can be processed into a wound wire shape, a twisted wire shape, a net shape, or the like, but gold, silver, and copper that have low resistance in terms of improving sound quality. It is desirable to use any one of the metal materials.

  Further, the maximum diameter of the wiring member 9 is about 1/2 to 3 times the thickness of the exciter 5 because the restraining force to the vibrator 5 and the frame 1 is weakened including the exciter 5. desirable.

  FIG. 3A is a plan view schematically showing the configuration of the acoustic generator of the second embodiment, and FIG. 3B is a cross-sectional view taken along the line B-B ′ in FIG.

  In the acoustic generator according to the second embodiment, it is desirable that the wiring member 9 has a flat part in the part 9 b and the flat part 9 b is connected to the external electrode 7.

  By making the portion 9b connected to the external electrode 7 thin in the moving direction of the exciter 5 (direction perpendicular to the surface of the vibrating body 3), the exciter 5 is deformed (bent), and the vibrating body 3 When the wiring member 9 is most bent, the stress from the restraint by the exciter 5 (or the vibrating body 3) and the frame body 1 can be further reduced. Thereby, the peak dip in the frequency characteristic of the sound pressure can be further reduced, and the sound pressure can be further stabilized.

  In this case, it is desirable that the portion 9b of the wiring member 9 connected to the external electrode 7 has a structure in which linear metal wires 9a are arranged in parallel. In the wiring member 9, a large number of wires are not intertwined with each other or overlapped so that a portion 9 b connected to the external electrode 7 is wound, twisted, or mesh-shaped, and a plurality of linear wires are formed. If the electrodes are arranged in parallel, the thickness of the external electrode 7 covering the wiring member 9 can be reduced. As a result, the stress on the exciter 5 caused by the external electrode 7 can be reduced, so that the peak dip in the frequency characteristic of the sound pressure can be further reduced, and thus the sound pressure can be further stabilized. it can.

  FIG. 4A is a plan view schematically showing the configuration of the sound generator of the third embodiment, and FIG. 4B is a sectional view taken along line B-B ′ in FIG.

  By adopting a structure in which the core material 9c is inserted into the metal wire 9a constituting the wiring member 9, permanent deformation of the wiring member 9 due to vibration of the exciter 5 and the vibrating body 3 can be suppressed. As a result, the ground state of the wiring member 9 when the exciter 5 does not vibrate can be maintained, so that the basic waveform of sound pressure can be maintained for a long time.

  In this case, it is preferable that the wiring member 9 does not have the core material 9c in at least a part of the portion 7b connected to the external electrode 7. If at least a part of the portion 7b connected to the external electrode 7 of the wiring member 9 is not provided with the core material 9c, stress relaxation to the exciter 5 is reduced, so when the exciter 5 vibrates at the peak time, Since the portion 7b connected to the external electrode 7 suppresses vibration, the entire exciter 5 is difficult to bend, and thus it is possible to suppress the peak dip of the sound pressure due to the bending of the exciter 5 itself.

  Here, the piezoelectric element serving as the exciter 5 is a laminated body having a pair of external electrodes at both ends in the longitudinal direction of a laminated body in which piezoelectric layers made of four ceramic layers and internal electrode layers are alternately laminated. In this case, the piezoelectric element is bonded onto the film as the vibrating body 3 via a bonding material. In this case, the shape of the piezoelectric element is preferably a plate shape because the acoustic generator can be made thinner, and the upper and lower main surfaces thereof are square, rectangular or polygonal. Any one of the shapes may be used. In this case, either a unimorph type or a bimorph type can be employed as the piezoelectric element.

  As a material of the piezoelectric element, for example, a ceramic selected from lead-free piezoelectric materials such as lead zirconate (PZ), lead zirconate titanate (PZT), Bi layered compound, tungsten bronze structure compound, and the like is applied. desirable.

  Further, in the above-described acoustic generator, it is preferable that resin is filled on the vibrating body 3 inside the frame body 1 so that the exciter 5 is embedded, whereby the exciter 5 and the vibrating body 3 are connected. It is possible to generate a stable vibration by being firmly joined. If a part of the wiring member 9 is embedded in the resin layer, vibration from the connection end with the outside of the wiring member 9 is difficult to be transmitted to the exciter 5, and noise is less likely to enter the sound pressure. good.

  In this case, as the material of the resin layer, an organic material such as an epoxy resin, an acrylic resin, a silicon resin, or rubber is used because the peak dip in the frequency characteristics of the sound generator can be reduced and the sound pressure can be reduced. It is desirable to use it.

  Moreover, as a material of an internal electrode layer and an external electrode, what has as a main component at least 1 sort (s) of metal chosen from silver and palladium is preferable, and you may include a piezoelectric material in this.

  As the frame 1, it is preferable to use a metal such as stainless steel for reasons of corrosion resistance and high strength, but plastic, engineering plastic, ceramics, etc. can also be used in terms of weight reduction. In this case, the thickness is desirably 100 to 1000 μm. The frame shape (the shape when viewed in plan) of the frame body 1 is not limited to the rectangular shape as shown in FIG. 1A, and a part or all of the frame shape is circular, elliptical, or rhombus. It is good.

  As a material for the film to be the vibrating body 3, for example, a resin such as polyethylene, polyimide, polypropylene, polystyrene, or tenn, or paper made of pulp, fiber, or the like can be used because the peak dip in the frequency characteristics of sound pressure can be reduced. It is better to select a material having a lower Young's modulus compared to metals and ceramics. In this case, it is desirable that the Young's modulus of the vibrating body 3 is lower than the Young's modulus of the frame 1.

  Next, of the first, second, and third embodiments described above, the procedure for producing the sound generator of the first embodiment will be described. Needless to say, the sound generators of the second and third embodiments can be manufactured by the same procedure.

  First, a plate-shaped laminated piezoelectric element having a substantially rectangular planar shape to be the exciter 5 is prepared.

  Next, a film to be the vibrating body 3 is prepared, and this film is fixed to the frame body 1.

  Next, a piezoelectric element having the external electrode 7 is bonded to a substantially central region of the surface of the vibrating body 3 via a bonding material. In this case, the bonding material is cured by heating or ultraviolet irradiation.

  Next, a wiring member 9 is prepared, and one end of the wiring member 9 is bonded to an external electrode formed on a piezoelectric element by using a bonding material such as solder or conductive resin, and a part in the middle of the other end side Is fixed to the frame 1 with an adhesive.

  Here, as the wiring member 9, what has the metal wire formed in the shape in any one of a winding form, a strand form, and a mesh shape is applied.

  In addition, when pouring resin inside the frame 1 and forming the resin layer which covers the exciter 5 and the vibrating body 3, the wiring member 9 is a resin layer except for the part connected to the external electrode 7. It is good to form so that it may become outside.

  The acoustic generator configured as described above has a wiring member 9 having a metal wire formed in any one of a wound shape, a twisted wire shape, a mesh shape, and a tinsel wire shape. It becomes a vessel.

Further, the sound generator described in the first embodiment can be configured as a sound generator, so-called “speaker device”, by being housed in a housing that houses the sound generator, a so-called resonance box. For example, if it can be configured as a large-sized speaker device used for televisions, personal computers, etc., it can be a medium-sized or small-sized device mounted on mobile terminals such as smartphones, mobile phones, PHS (Personal Handyphone System), and PDA (Personal Digital Assistants). It can also be configured as a speaker device. In addition, a speaker apparatus is not limited to said use, It can comprise as a speaker apparatus mounted in arbitrary electronic devices, such as a vacuum cleaner, a washing machine, and a refrigerator.

  Furthermore, the sound generator described in the first embodiment includes at least an electronic circuit connected to the sound generator, and a housing that houses the electronic circuit and the sound generator. It can also be configured as an electronic device having a function of generating sound from the sound. Examples of such electronic devices include televisions, personal computers, various mobile terminals, portable terminals, mobile terminals, vacuum cleaners, washing machines, refrigerators, and the like. Examples of such electronic devices include various terminal devices such as a car navigation system installed in an automobile, an in-vehicle device that generates a warning sound, and the like.

1, 101 ·········· Frame 3, 103 ············· Vibratory member 5, 105 ············ Exciter 7, 107 ··· .... External electrodes 9, 109 ...... Wiring member 9a ... Metal wire 9b ... Wiring member Part of the body (flat part)
9c ... Core material

Claims (8)

An exciter having an external electrode and vibrating in response to an electrical signal;
A vibrator that is mounted with the exciter and vibrates with the exciter by vibration of the exciter;
A wiring member connected to the external electrode provided in the exciter and for inputting an electric signal to the exciter;
The acoustic generator according to claim 1, wherein the wiring member has a metal wire formed in one of a winding shape, a stranded wire shape, and a mesh shape.   The sound generator according to claim 1, wherein the exciter is a piezoelectric element.   The acoustic generator according to claim 1, wherein a part of the wiring member has a flat shape, and the flat part is connected to the external electrode.   The acoustic generator according to any one of claims 1 to 3, wherein the wiring member in a portion connected to the external electrode has a structure in which linear metal wires are arranged in parallel.   The sound generator according to any one of claims 1 to 4, wherein the wiring member has a structure in which the metal wire surrounds a core material.   The sound generator according to claim 5, wherein the wiring member does not have the core material in at least a part of a portion connected to the external electrode. A sound generator comprising: the sound generator according to claim 1; and a housing that houses the sound generator. The sound generator according to any one of claims 1 to 6,
An electronic circuit connected to the acoustic generator;
A housing for housing the electronic circuit and the acoustic generator;
An electronic device having a function of generating sound from the sound generator.

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