WO2017029828A1 - Sound generator, sound generation device and electronic apparatus - Google Patents

Sound generator, sound generation device and electronic apparatus Download PDF

Info

Publication number
WO2017029828A1
WO2017029828A1 PCT/JP2016/058072 JP2016058072W WO2017029828A1 WO 2017029828 A1 WO2017029828 A1 WO 2017029828A1 JP 2016058072 W JP2016058072 W JP 2016058072W WO 2017029828 A1 WO2017029828 A1 WO 2017029828A1
Authority
WO
WIPO (PCT)
Prior art keywords
sound
sound generator
opening
plate member
generator
Prior art date
Application number
PCT/JP2016/058072
Other languages
French (fr)
Japanese (ja)
Inventor
長岡　聡史
Original Assignee
京セラ株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 京セラ株式会社 filed Critical 京セラ株式会社
Priority to JP2017535251A priority Critical patent/JPWO2017029828A1/en
Publication of WO2017029828A1 publication Critical patent/WO2017029828A1/en

Links

Images

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R1/00—Details of transducers, loudspeakers or microphones
    • H04R1/02—Casings; Cabinets ; Supports therefor; Mountings therein
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R1/00—Details of transducers, loudspeakers or microphones
    • H04R1/20—Arrangements for obtaining desired frequency or directional characteristics
    • H04R1/22—Arrangements for obtaining desired frequency or directional characteristics for obtaining desired frequency characteristic only 
    • H04R1/28—Transducer mountings or enclosures modified by provision of mechanical or acoustic impedances, e.g. resonator, damping means
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R1/00—Details of transducers, loudspeakers or microphones
    • H04R1/20—Arrangements for obtaining desired frequency or directional characteristics
    • H04R1/32—Arrangements for obtaining desired frequency or directional characteristics for obtaining desired directional characteristic only
    • H04R1/34—Arrangements for obtaining desired frequency or directional characteristics for obtaining desired directional characteristic only by using a single transducer with sound reflecting, diffracting, directing or guiding means
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R17/00—Piezoelectric transducers; Electrostrictive transducers

Definitions

  • the present invention relates to a sound generator, a sound generator, and an electronic device.
  • an acoustic generator using a piezoelectric element is known (for example, see Patent Document 1).
  • Such an acoustic generator is configured to vibrate a diaphragm by applying a voltage to a piezoelectric element attached to the diaphragm to vibrate, and to output sound by actively utilizing resonance of the vibration.
  • Such sound generators are used as sound sources for liquid crystal televisions and personal computers.
  • a sound emitting hole (a slit structure opening) is provided on the wall surface of a liquid crystal television case for improving design, and a sound generator is attached so as to emit sound from the sound emitting hole.
  • An acoustic generator is used (for example, refer to Patent Documents 2 and 3).
  • JP 2001-16692 A Japanese Patent Laid-Open No. 2004-193749 International Publication No. 2012/063490
  • FIG. 1 shows an example of a sound generating device in which a sound generator of one example of the present embodiment is attached to a plate member having an opening
  • (a) is a plan view
  • (b) is a cross-sectional view along the line AA
  • (c) Is a cross-sectional view taken along line BB.
  • (A) is a general
  • (b) is a partial transmission side view of the acoustic generator shown in (a).
  • A) is a general
  • (b) is a partially permeable side view of the sound generator shown to (a).
  • FIG. 2 shows another example of a sound generator in which a sound member of another example of the present embodiment is attached to a plate member having an opening, (a) is a plan view, and (b) is a cross-sectional view taken along line AA. , (C) is a cross-sectional view taken along line BB.
  • FIG. 2 shows another example of a sound generator in which a sound member of another example of the present embodiment is attached to a plate member having an opening, (a) is a plan view, and (b) is a cross-sectional view taken along line AA.
  • FIG. 2 shows another example of a sound generator in which a sound member of another example of the present embodiment is attached to a plate member having an opening, (a) is a plan view, and (b) is a cross-sectional view taken along line AA. , (C) is a cross-sectional view taken along line BB.
  • FIG. 1 shows a sound generator in which a sound generator of an example of the present embodiment is attached to a plate member having an opening, (a) is a plan view, (b) is a cross-sectional view taken along line AA, c) is a cross-sectional view taken along line BB.
  • 2A is a schematic enlarged plan view of an example of the sound generator shown in FIG. 1, and FIG. 2B is a partially transparent side view of the sound generator shown in FIG.
  • the same reference numerals are used for the same components.
  • an acoustic generator 12 is attached to an inner wall surface 1 (hereinafter simply referred to as a wall surface 1) of a plate member 11 having an opening 10 so as to face the opening 10.
  • a wall surface 1 hereinafter simply referred to as a wall surface 1
  • the sound generator 41 includes a plate member 11 having an opening 10 and a sound generator 12 attached to the wall surface 1 of the plate member 11 so as to face the opening 10.
  • the acoustic generator 12 shown in FIGS. 1 and 2 includes a piezoelectric element 23, a diaphragm 22 to which the piezoelectric element 23 is attached, and a piezoelectric speaker having a frame 21 that supports an outer peripheral portion of at least one main surface of the diaphragm 22. 2 is provided.
  • the sound generator 12 is connected to the wall surface 1 of the plate member 11 having an opening at one end together with the fixing portion 31 that fixes the outer peripheral portion of the piezoelectric speaker 2, and is surrounded between the wall surface 1 and the piezoelectric speaker 2.
  • the holding member 3 including the frame-like portion 32 that forms a space is provided. Further, in the sound generator 12, the frame-like portion 32 includes an open portion 13 in which at least a part of the space is open. Below, the piezoelectric speaker 2 is demonstrated first.
  • the configuration of the piezoelectric element 23 used in the piezoelectric speaker 2 constituting the acoustic generator 12 of the present embodiment is not shown, but for example, a piezoelectric layer and an internal electrode layer are laminated to form a plate shape.
  • the laminated body was provided.
  • the piezoelectric element 23 includes an external electrode provided on the side surface from which the internal electrode layer of the multilayer body is derived, and a surface electrode connected to the external electrode and provided on the main surface of the multilayer body. .
  • the piezoelectric element 23 is attached to the main surface of the vibration plate 22 or the like, and excites the vibration plate 22 by vibrating under application of a voltage.
  • the piezoelectric layer constituting the piezoelectric element 23 is formed of ceramics having piezoelectric characteristics.
  • Conventionally used piezoelectric ceramics such as lead-free piezoelectric materials such as lead zirconate titanate, lithium niobate, lithium tantalate, Bi layered compounds, and tungsten bronze structure compounds are used as such ceramics. it can.
  • the thickness of the piezoelectric layer is set to 0.04 to 1.0 mm, for example. In order to obtain a large bending vibration, it is preferable to have a piezoelectric constant d31 of 200 pm / V or more.
  • the internal electrode layer constituting the piezoelectric element 23 is formed by simultaneous firing with the ceramic forming the piezoelectric layer. It consists of a first internal electrode layer and a second internal electrode layer, and is alternately laminated with piezoelectric layers to sandwich the piezoelectric layers from above and below.
  • a material for forming the internal electrode layer various metal materials can be used.
  • a conductor mainly composed of silver or silver-palladium that can be fired at a low temperature, or a conductor containing copper, platinum, or the like can be used, but these may contain a ceramic component or a glass component.
  • the internal electrode layer is made of a material containing a metal component composed of silver and palladium and a ceramic component that constitutes the piezoelectric layer, the stress due to the thermal expansion difference between the piezoelectric layer and the internal electrode layer is reduced. Therefore, it is possible to obtain the piezoelectric element 23 having no stacking failure.
  • a main body on the upper surface side and the lower surface side may be a plate-like body having a polygonal shape such as a rectangular shape or a square shape, or a circular shape or an elliptical shape.
  • the piezoelectric element 23 may have, for example, a monomorph structure with one piezoelectric layer, but preferably has a bimorph structure with two or more piezoelectric layers. Thereby, while contributing to thickness reduction, the diaphragm 22 can be efficiently vibrated with less energy. Further, in a bimorph structure in which the direction of displacement due to an electric field applied at a certain moment is reversed between the one side and the other side in the thickness direction, the piezoelectric element 23 itself undergoes flexural vibration, whereby the diaphragm Since the mechanical loss at the joint surface with 22 can be reduced, the sound pressure can be improved.
  • the diaphragm 22 can be formed using various materials such as resin and metal.
  • the diaphragm 22 can be made of a resin film such as polyethylene or polyimide having a thickness of 10 to 200 ⁇ m.
  • the piezoelectric element 23 is bonded to the diaphragm 22 with an adhesive such as an epoxy resin, an acrylic resin, or a rubber resin, and the diaphragm 22 vibrates due to the vibration of the piezoelectric element 23.
  • a wiring member (not shown) is connected to the surface electrode of the piezoelectric element 23, and an electric signal is input to the piezoelectric element 23 through this wiring member, so that the piezoelectric element 23 is in the in-plane direction (the main surface of the diaphragm 22 When the diaphragm 22 is extended in a direction parallel to the piezoelectric element 23, the diaphragm 22 itself is not displaced by an electric signal.
  • the diaphragm 22 is bent so as to be convex toward the piezoelectric element 23 side.
  • the piezoelectric element 23 contracts in the in-plane direction, and the vibration plate 22 itself is not displaced by the electric signal. Bend to be concave. That is, by applying an AC signal to the piezoelectric element 23, the piezoelectric element 23 can be expanded and contracted in the in-plane direction, and bending vibration can be applied to the diaphragm 22.
  • the frame body 21 is provided so as to support the outer peripheral portion of the main surface of the diaphragm 22.
  • the frame body 21 for example, a member whose inner peripheral shape and outer peripheral shape are rectangular can be used.
  • the frame body 21 is provided so as to sandwich both main surfaces of the diaphragm 22.
  • the thickness of the frame body 21 may be 100 to 5000 ⁇ m, for example.
  • various materials such as glass, a metal, and resin, can be used, for example.
  • glass or metal since the rigidity is high, the deformation is small and the sound quality is stable.
  • resin since it is less rigid than glass or metal and easily deforms due to vibration of the diaphragm 22, it is easy to induce spurious vibrations in the resonance of the diaphragm 22. Therefore, resonance peaks are dispersed in the sound pressure characteristics, and the peaks and dip can be reduced, and the frequency characteristics can be flattened. Therefore, the sound quality can be improved by flattening the sound pressure.
  • the frame body 21 is not particularly limited as long as it can support the diaphragm 22.
  • the outer peripheral shape of the frame body 21 is a rectangular shape and the inner peripheral shape is also a rectangular shape and the aspect ratio is larger than 1, it contributes to the dispersion of resonance. , Can contribute to reduction of peaks and dip.
  • it may be a polygon such as a square, a parallelogram, a trapezoid, and a regular n-gon, or a circle or an ellipse.
  • a resin layer 24 may be provided in the frame of the frame body 21 so as to cover the piezoelectric element 23.
  • FIGS. 1 and 2 show examples in which the resin layer 24 is provided.
  • a plate member 11 which is a part of the casing of the liquid crystal television is provided with an opening 10 having a slit structure as a sound emitting hole. It is set as the structure which emits a sound from 10 (sound emitting hole).
  • the piezoelectric speaker 2 is attached to the plate member 11 (wall surface 1) having the opening 10 so as to face the opening 10.
  • the acoustic generator 12 of the present embodiment includes a holding member 3 for attaching the piezoelectric speaker 2 to the plate member 11.
  • the holding member 3 fixes the outer peripheral portion of the piezoelectric speaker 2 and one end is connected to the wall surface 1 of the plate member 11 to form a space surrounded by the wall surface 1 of the plate member 11 and the piezoelectric speaker 2.
  • the holding member 3 includes a fixed portion 31 that fixes the outer peripheral portion of the piezoelectric speaker 2 and a frame-shaped portion 32 that is configured to form an open portion 13 in which at least a part of the space is open.
  • FIG. 1 an example in which the holding member 3 is configured by the fixed portion 31 and the frame-shaped portion 32 is illustrated, but these may be configured integrally.
  • the frame-shaped portion 32 is configured to form the open portion 13 in which at least a part of the space is open.
  • Sound generators are required to improve the sound quality of sound generated from openings (sound holes).
  • openings sound holes.
  • the opening of the slit structure is narrow, there is a problem that the high frequency sound cannot be sufficiently reproduced in the sound emitted from the sound emission hole, and it has been demanded that the high frequency sound can be sufficiently reproduced. .
  • the compression of sound between the sound generator 12 and the wall surface 1 of the plate member 11 having the opening 10 can be suppressed, and a low sound near the lowest resonance frequency of the sound generator 12 can be suppressed.
  • the frequency characteristics are flattened without being enhanced. Thereby, it can be set as the sound generator 12 excellent in the reproduction
  • the open portion 13 is a passage that connects an internal space inside the frame-shaped portion 32 and an external space outside the frame-shaped portion 32.
  • the open portion 13 has a shape provided so as to be cut out along the long side of a rectangular frame-like member in plan view.
  • the shape is not limited to such a shape, and may be a shape provided such that a part of the long side of the rectangular frame-shaped portion 32 is cut out in a plan view as shown in FIG. 4 may be a shape like a through-hole provided on the long side of the rectangular frame-shaped portion 32 in plan view.
  • the open portion 13 in the frame-shaped portion 32 is at least the size of the opening 10 of the plate member 11.
  • the opening portion 13 is larger in size than the opening portion 10 when the opening portion 13 and the opening portion 10 are viewed from the front.
  • the opening portion 13 has a larger opening area than the opening portion 10. Means. Thereby, a part of the sound generated by the piezoelectric speaker 2 is efficiently emitted from the open part 13 of the frame-shaped part 32, and an acoustic generator having excellent high-frequency sound reproduction capability can be obtained.
  • the opening part 13 of the frame-shaped part 32 is larger than the opening part 10, as shown in FIG.1 and FIG.2, the opening part 10 is a rectangular-shaped slit, Comprising:
  • the external shape of the shape part 32 is a rectangular shape, it is preferable that the open part 13 is made into the shape notched along the rectangular long side.
  • the fixing part 31 and the frame-like part 32 in the holding member 3 can be made of various materials such as metal, ABS, polystyrene, polypropylene, polycarbonate, and resins such as alloy resins thereof.
  • the open portion 13 may be formed by processing so as to cut out the frame-shaped portion 32, or may be formed in such a shape from the beginning by injection molding or the like.
  • FIG. 5A and 5B show a sound generator 42 in which the sound generator 16 of another example of the present embodiment is attached to the plate member 11 having the opening 10, wherein FIG. 5A is a plan view, and FIG. A cross-sectional view taken along line A, and (c) is a cross-sectional view taken along line BB.
  • the sound generator 42 shown in FIG. 5 is different from the sound generator 41 shown in FIG. 1 in that a frequency characteristic adjusting member 4 is provided on one end side of the holding member 3 in the sound generator 16.
  • the one end side of the holding member 3 means a portion located between the diaphragm 22 of the piezoelectric speaker 2 and the wall surface 1 of the plate member 11 in the fixing portion 31 or the frame-like portion 32 of the holding member 3. To do.
  • the frequency characteristic adjusting member 4 By providing the frequency characteristic adjusting member 4 on one end side of the holding member 3, the frequency characteristic adjusting member 4 partially blocks the reflection of sound. Thereby, the peak dip of the frequency characteristic due to sound reflection generated between the acoustic generator 14 and the wall surface 1 of the plate member 11 having the opening 10 can be further reduced.
  • the frequency characteristic adjusting member 4 only needs to block a part of the sound reflection generated between the piezoelectric speaker 2 and the wall surface 1 of the plate member 11 having the opening 10, and the shape, size, and number thereof are particularly limited. There is no limitation, and it may be appropriately adjusted according to the frequency characteristics of the sound generator 16.
  • two frequency characteristic adjusting members 4 connected to the fixed portion 31 are provided in a shape extending in the in-plane direction of the wall surface 1 of the plate member 11 so as to cross the opening 10 in the width direction.
  • it may be one, for example, and may be further connected to the frame part 32.
  • a plurality of piezoelectric elements 23 may be arranged so as to be positioned between these piezoelectric elements 23 in plan view.
  • the frequency characteristic adjusting member 4 may be made of a material that can block a part of sound reflection generated between the piezoelectric speaker 2 and the wall surface 1 of the plate member 11 having the opening 10. The same material as the part 31 can be used.
  • FIG. 6 shows a sound generator 43 in which the sound generator 17 of still another example of the present embodiment is attached to the plate member 11 having the opening 10, wherein (a) is a plan view and (b) is A. A cross-sectional view taken along line -A, and (c) is a cross-sectional view taken along line BB.
  • the one end side of the holding member 3 here also means a portion located between the diaphragm 22 of the piezoelectric speaker 2 and the wall surface 1 of the plate member 11 in the fixed portion 31 or the frame-like portion 32 of the holding member 3. .
  • the reflected sound related to the peak dip of the frequency characteristic can be absorbed by the sound absorbing material 5, and the frequency characteristic can be further flattened.
  • the sound absorbing material 5 only needs to be able to absorb a part of sound reflection generated between the sound generator 17 and the wall surface 1 of the plate member 11 having the opening 10, and the shape, size, and number thereof are not particularly limited. However, it may be adjusted appropriately according to the frequency characteristics of the sound generator 12.
  • FIG. 6 shows an example in which two frames are provided at both ends on one side of the frame-like portion 32. For example, four frames may be provided at all ends instead of only at one end. Furthermore, it may be provided along the inner surface of the frame-shaped portion 32.
  • the sound absorbing material 5 may be any material that absorbs part of the sound reflection generated between the sound generator 15 and the wall surface 1 of the plate member 11 having the opening 10.
  • urethane foam, foam rubber Cotton fiber or the like can be used.
  • FIG. 7 shows a sound generator 44 in which the sound generator 18 of still another example of the present embodiment is attached to the plate member 11 having the opening 10, (a) is a plan view, and (b) is A A cross-sectional view taken along line -A, and (c) is a cross-sectional view taken along line BB.
  • the sound generator 15 is attached so that the center of the opening 10 of the wall surface 1 and the center of the piezoelectric speaker 2 are shifted from each other. Since the frequency characteristics of the reflected sound generated between the wall member 1 and the wall surface 1 of the plate member 11 vary, the frequency characteristics can be made flatter.
  • the opening 10 is in a range inside the frame-shaped part 32 when viewed through a plane. It is preferable to make it shift within.
  • the attachment of the opening 10 so that the opening 10 is displaced within the range inside the frame-like portion 32, and the opening 10 It is preferable to attach so that the distance between and is different.
  • the distance between the open portion 13 of the frame-shaped portion 32 and the opening 10 of the plate member 11 is different, so that the resonance frequency depending on the distance between the wall surface 1 of the plate member 11 and the opening 10 is changed. Since there is no significant peak dip due to concentration, the frequency characteristics can be made flatter.
  • FIG. 8 is a block diagram illustrating an example of the electronic apparatus of the present embodiment.
  • the electronic device 50 of this example includes an acoustic generator 12, an electronic circuit 60 connected to the acoustic generator 12, and a housing 70 that houses the electronic circuit 60 and the acoustic generator 12. And having a function of generating sound from the sound generator 12.
  • the electronic device 50 includes a plate member in which a part of the housing 70 has an opening, and the opening is formed with respect to the plate member having an opening that is a part of the housing 70.
  • a sound generator is attached so as to oppose.
  • the electronic circuit 60 includes, for example, a controller 50a, a transmission / reception unit 50b, a key input unit 50c, and a microphone input unit 50d.
  • the electronic circuit 60 is connected to the sound generator 12 and has a function of outputting an audio signal to the sound generator 12.
  • the sound generator 12 generates sound based on the sound signal input from the electronic circuit 60.
  • the electronic device 50 includes a display unit 50e and an antenna 50f, and these are housed in the housing 70 including the above-described devices.
  • FIG. 8 shows a state in which each device including the controller 50a is accommodated in one casing 70, the accommodation form of each device is not limited. In the present embodiment, it is only necessary that at least the electronic circuit 60 and the sound generator 12 are accommodated in one housing 70.
  • the controller 50 a is a control unit of the electronic device 50.
  • the transmission / reception unit 50b transmits / receives data via the antenna 50f based on the control of the controller 50a.
  • the key input unit 50c is an input device of the electronic device 50 and accepts a key input operation by an operator.
  • the microphone input unit 50d is also an input device of the electronic device 50, and accepts a voice input operation by an operator.
  • the display unit 50e is a display output device of the electronic device 50, and outputs display information based on the control of the controller 50a.
  • the acoustic generator 12 operates as an acoustic output device in the electronic device 50.
  • the sound generator 12 is connected to the controller 50a of the electronic circuit 60, and emits sound upon application of a voltage controlled by the controller 50a.
  • the electronic device 50 is described as a portable terminal device.
  • the electronic device 50 is not limited to the type of the electronic device 50, and may be applied to various consumer devices having a function of emitting sound.
  • flat-screen televisions and car audio devices can of course be used for products having a function of generating sound, for example, various products such as vacuum cleaners, washing machines, refrigerators, microwave ovens, and the like.
  • the electronic device 50 according to the present embodiment described above includes the sound generator 12 having an excellent high frequency sound reproduction capability, the electronic device 50 having an excellent high frequency sound reproduction capability can be obtained. .
  • a long plate shape having a length of 297 mm, a width of 210 mm, and a thickness of 4 mm and a material made of ABS resin was prepared.
  • the opening was 28 mm in length, 3 mm in width, and 4 mm in thickness.
  • the piezoelectric speaker constituting a part of the sound generator has a length of 30 mm, a width of 10 mm, a thickness of 15 ⁇ m, a material made of polyetherimide, a length of 7 mm, a width of 6 mm, and a thickness of 0.1 mm.
  • a piezoelectric element made of a piezoelectric material is attached, and the main surface of the diaphragm is 30 mm in length, 10 mm in width, 1 mm in thickness with a square shape, the width of the square shape is 1 mm, and the material is stainless steel
  • a frame made of steel was attached. The piezoelectric element was embedded in the frame with a thermosetting epoxy resin.
  • the piezoelectric speaker is formed into a U-shape having a length of 34 mm, a width of 14 mm, and a thickness of 3 mm, a U-shaped width of 3 mm, and a material made of ABS.
  • a generator was produced, and this was bonded to the plate member with an adhesive so as to face the opening, thereby forming a first sound generator of the form as shown in FIGS.
  • the frequency characteristic adjusting material 4 is a plate having a length of 34 mm, a width of 3 mm, and a thickness of 1 mm, and two materials made of ABS, in-plane direction of the wall surface
  • a second sound generation device having a configuration as shown in FIG. 5 was produced by attaching to a holding member as a shape extending across the opening.
  • the second sound generator two sound absorbing materials having a length of 4 mm, a width of 4 mm, and a thickness of 1 mm are arranged at both ends on one side of the holding member as shown in FIG.
  • a third acoustic generator of the form was produced.
  • the material of the sound absorbing material was urethane foam.
  • the holding member and the sound generator are arranged with a shift of 2 mm in the long side direction from the center position of the opening of the wall surface, and the fourth sound generator having a form as shown in FIG. Produced.
  • a square-shaped holding member having a length of 34 mm, a width of 14 mm, and a thickness of 3 mm was bonded to the above piezoelectric speaker to produce a sound generator of a comparative example.
  • a frequency sweep test from 1 kHz to 100 kHz was performed on the piezoelectric element at a voltage of an effective value ⁇ 7 Vrms at a frequency of 1 kHz, and the frequency characteristics were measured.
  • FIG. 9 shows the results of the fourth sound generator.
  • the sound generator of this embodiment shown in FIG. 10 to FIG. 13 can reduce the peak around 10 kHz compared with the sound generator shown in FIG. It was confirmed that the sound generator was excellent in sound reproduction ability.

Landscapes

  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Acoustics & Sound (AREA)
  • Signal Processing (AREA)
  • Health & Medical Sciences (AREA)
  • Otolaryngology (AREA)
  • Piezo-Electric Transducers For Audible Bands (AREA)
  • Diaphragms For Electromechanical Transducers (AREA)
  • Details Of Audible-Bandwidth Transducers (AREA)

Abstract

[Problem] To provide a sound generator, a sound generation device and an electronic apparatus which have excellent high-frequency sound reproduction capability. [Solution] The present invention is a sound generator 12 that is attached to a plate member 11 so as to face an opening 10 of the plate member 11. The sound generator 12 is provided with: a piezoelectric speaker 2 comprising a diaphragm 22 to which a piezoelectric element 23 is attached, and a frame 21 which supports an outer peripheral portion of at least one principal surface of the diaphragm 22; and a holding member 3 which secures an outer peripheral portion of the piezoelectric speaker 2 and has one end connected to the plate member 11 to thereby form an enclosed space between the plate member 11 and the piezoelectric speaker 2, and is characterized in that the holding member 3 is provided with a frame-shaped portion 32 configured to form an open portion 13 through which at least part of the space is opened.

Description

音響発生器、音響発生装置ならびに電子機器Sound generator, sound generator and electronic device
　本発明は、音響発生器、音響発生装置ならびに電子機器に関するものである。 The present invention relates to a sound generator, a sound generator, and an electronic device.
　従来、圧電素子を用いた音響発生器が知られている（例えば、特許文献１参照。）。かかる音響発生器は、振動板に取り付けた圧電素子に電圧を印加して振動させることによって振動板を振動させ、かかる振動の共振を積極的に利用することで音響を出力するものである。 Conventionally, an acoustic generator using a piezoelectric element is known (for example, see Patent Document 1). Such an acoustic generator is configured to vibrate a diaphragm by applying a voltage to a piezoelectric element attached to the diaphragm to vibrate, and to output sound by actively utilizing resonance of the vibration.
　このような音響発生器は、液晶テレビやパソコン等の音源として用いられている。例えば、デザイン性向上のために液晶テレビの筐体の壁面に放音孔（スリット構造の開口部）を設け、該放音孔より音を発するように音響発生器が取り付けられた構成とされて、音響発生器は用いられる（例えば、特許文献２、３参照。）。 Such sound generators are used as sound sources for liquid crystal televisions and personal computers. For example, a sound emitting hole (a slit structure opening) is provided on the wall surface of a liquid crystal television case for improving design, and a sound generator is attached so as to emit sound from the sound emitting hole. An acoustic generator is used (for example, refer to Patent Documents 2 and 3).
特開２００１－１６６９２号公報JP 2001-16692 A 特開２００４－１９３７４９号公報Japanese Patent Laid-Open No. 2004-193749 国際公開第２０１２／０６３４９０号公報International Publication No. 2012/063490
開口部を有する板部材に、本実施形態の一例の音響発生器が取り付けられた音響発生装置の一例を示し、（ａ）は平面図、（ｂ）はＡ－Ａ線断面図、（ｃ）はＢ－Ｂ線断面図である。1 shows an example of a sound generating device in which a sound generator of one example of the present embodiment is attached to a plate member having an opening, (a) is a plan view, (b) is a cross-sectional view along the line AA, (c) Is a cross-sectional view taken along line BB. （ａ）は図１に示す音響発生器の一例の概略拡大平面図、（ｂ）は（ａ）に示す音響発生器の一部透過側面図である。(A) is a general | schematic enlarged plan view of an example of the acoustic generator shown in FIG. 1, (b) is a partial transmission side view of the acoustic generator shown in (a). （ａ）は音響発生器の他の例の概略拡大平面図、（ｂ）は（ａ）に示す音響発生器の一部透過側面図である。(A) is a general | schematic expanded plan view of the other example of a sound generator, (b) is a partially permeable side view of the sound generator shown to (a). （ａ）は音響発生器の他の例の概略拡大平面図、（ｂ）は（ａ）に示す音響発生器の一部透過側面図である。(A) is a general | schematic expanded plan view of the other example of a sound generator, (b) is a partially permeable side view of the sound generator shown to (a). 開口部を有する板部材に、本実施形態の他の一例の音響発生器が取り付けられた音響発生装置の他の一例を示し、（ａ）は平面図、（ｂ）はＡ－Ａ線断面図、（ｃ）はＢ－Ｂ線断面図である。FIG. 2 shows another example of a sound generator in which a sound member of another example of the present embodiment is attached to a plate member having an opening, (a) is a plan view, and (b) is a cross-sectional view taken along line AA. , (C) is a cross-sectional view taken along line BB. 開口部を有する板部材に、本実施形態の他の一例の音響発生器が取り付けられた音響発生装置の他の一例を示し、（ａ）は平面図、（ｂ）はＡ－Ａ線断面図、（ｃ）はＢ－Ｂ線断面図である。FIG. 2 shows another example of a sound generator in which a sound member of another example of the present embodiment is attached to a plate member having an opening, (a) is a plan view, and (b) is a cross-sectional view taken along line AA. , (C) is a cross-sectional view taken along line BB. 開口部を有する板部材に、本実施形態の他の一例の音響発生器が取り付けられた音響発生装置の他の一例を示し、（ａ）は平面図、（ｂ）はＡ－Ａ線断面図、（ｃ）はＢ－Ｂ線断面図である。FIG. 2 shows another example of a sound generator in which a sound member of another example of the present embodiment is attached to a plate member having an opening, (a) is a plan view, and (b) is a cross-sectional view taken along line AA. , (C) is a cross-sectional view taken along line BB. 本実施形態の電子機器の一例を示すブロック図である。It is a block diagram which shows an example of the electronic device of this embodiment. 従来例の周波数特性を示す図である。It is a figure which shows the frequency characteristic of a prior art example. 本実施形態の一例の音響発生器の周波数特性を示す図である。It is a figure which shows the frequency characteristic of the acoustic generator of an example of this embodiment. 本実施形態の他の一例の音響発生器の周波数特性を示す図である。It is a figure which shows the frequency characteristic of the acoustic generator of the other example of this embodiment. 本実施形態のさらに他の一例の音響発生器の周波数特性を示す図である。It is a figure which shows the frequency characteristic of the acoustic generator of another example of this embodiment. 本実施形態のさらに他の一例の音響発生器の周波数特性を示す図である。It is a figure which shows the frequency characteristic of the acoustic generator of another example of this embodiment.
　以下、添付図面を参照して、本実施形態の一例を詳細に説明する。なお、以下に示す実施形態によりこの発明が限定されるものではない。 Hereinafter, an example of this embodiment will be described in detail with reference to the accompanying drawings. In addition, this invention is not limited by embodiment shown below.
　図１は、開口部を有する板部材に、本実施形態の一例の音響発生器が取り付けられた音響発生装置を示し、（ａ）は平面図、（ｂ）はＡ－Ａ線断面図、（ｃ）はＢ－Ｂ線断面図である。また、図２（ａ）は図１に示す音響発生器の一例の概略拡大平面図、図２（ｂ）は図２（ａ）に示す音響発生器の一部透過側面図である。なお、以下の図面の説明において、同一の構成については同一の符号を用いるものとする。 FIG. 1 shows a sound generator in which a sound generator of an example of the present embodiment is attached to a plate member having an opening, (a) is a plan view, (b) is a cross-sectional view taken along line AA, c) is a cross-sectional view taken along line BB. 2A is a schematic enlarged plan view of an example of the sound generator shown in FIG. 1, and FIG. 2B is a partially transparent side view of the sound generator shown in FIG. In the following description of the drawings, the same reference numerals are used for the same components.
　図１においては、開口部１０を有する板部材１１の内壁面１（以下、単に壁面１という。）に対し、開口部１０と対向して音響発生器１２が取り付けられて、音響発生装置４１が構成されている例を示している。すなわち、音響発生装置４１は、開口部１０を有する板部材１１と、当該板部材１１の壁面１に開口部１０と対向して取り付けられた音響発生器１２とを備えたものである。 In FIG. 1, an acoustic generator 12 is attached to an inner wall surface 1 (hereinafter simply referred to as a wall surface 1) of a plate member 11 having an opening 10 so as to face the opening 10. An example of a configuration is shown. That is, the sound generator 41 includes a plate member 11 having an opening 10 and a sound generator 12 attached to the wall surface 1 of the plate member 11 so as to face the opening 10.
　図１および図２に示す音響発生器１２は、圧電素子２３、圧電素子２３が取り付けられた振動板２２および振動板２２の少なくとも一方の主面の外周部を支持する枠体２１を有する圧電スピーカー２を備える。また、音響発生器１２は、圧電スピーカー２の外周部を固定する固定部３１とともに、一端が開口部を有する板部材１１の壁面１と接続されて壁面１と圧電スピーカー２との間に囲まれた空間を形成する枠状部３２からなる保持部材３を備えている。さらに、音響発生器１２は、枠状部３２は前記空間の少なくとも一部が開放された開放部１３を備えている。以下に、まず圧電スピーカー２について説明する。 The acoustic generator 12 shown in FIGS. 1 and 2 includes a piezoelectric element 23, a diaphragm 22 to which the piezoelectric element 23 is attached, and a piezoelectric speaker having a frame 21 that supports an outer peripheral portion of at least one main surface of the diaphragm 22. 2 is provided. The sound generator 12 is connected to the wall surface 1 of the plate member 11 having an opening at one end together with the fixing portion 31 that fixes the outer peripheral portion of the piezoelectric speaker 2, and is surrounded between the wall surface 1 and the piezoelectric speaker 2. The holding member 3 including the frame-like portion 32 that forms a space is provided. Further, in the sound generator 12, the frame-like portion 32 includes an open portion 13 in which at least a part of the space is open. Below, the piezoelectric speaker 2 is demonstrated first.
　本実施形態の音響発生器１２を構成する圧電スピーカー２に用いられる圧電素子２３としては、その構成を図示していないが、例えば、圧電体層と内部電極層とが積層されて板状に形成された積層体を備えている。また、圧電素子２３は、この積層体の内部電極層が導出された側面に設けられた外部電極と、この外部電極に接続されて積層体の主面に設けられた表面電極とを備えている。この圧電素子２３は、振動板２２の主面に貼り付けられるなどして取り付けられ、電圧の印加を受けて振動することによって振動板２２を励振させる。 The configuration of the piezoelectric element 23 used in the piezoelectric speaker 2 constituting the acoustic generator 12 of the present embodiment is not shown, but for example, a piezoelectric layer and an internal electrode layer are laminated to form a plate shape. The laminated body was provided. The piezoelectric element 23 includes an external electrode provided on the side surface from which the internal electrode layer of the multilayer body is derived, and a surface electrode connected to the external electrode and provided on the main surface of the multilayer body. . The piezoelectric element 23 is attached to the main surface of the vibration plate 22 or the like, and excites the vibration plate 22 by vibrating under application of a voltage.
　圧電素子２３を構成する圧電体層は圧電特性を有するセラミックスで形成されたものである。このようなセラミックスとして、チタン酸ジルコン酸鉛、ニオブ酸リチウム、タンタル酸リチウム、Ｂｉ層状化合物、タングステンブロンズ構造化合物等の非鉛系圧電体材料等、従来から用いられている圧電セラミックスを用いることができる。圧電体層の厚みは例えば０．０４～１．０ｍｍに設定される。また、大きな屈曲振動を得るために、２００ｐｍ／Ｖ以上の圧電定数ｄ３１を有することが好ましい。 The piezoelectric layer constituting the piezoelectric element 23 is formed of ceramics having piezoelectric characteristics. Conventionally used piezoelectric ceramics such as lead-free piezoelectric materials such as lead zirconate titanate, lithium niobate, lithium tantalate, Bi layered compounds, and tungsten bronze structure compounds are used as such ceramics. it can. The thickness of the piezoelectric layer is set to 0.04 to 1.0 mm, for example. In order to obtain a large bending vibration, it is preferable to have a piezoelectric constant d31 of 200 pm / V or more.
　また、圧電素子２３を構成する内部電極層は、圧電体層を形成するセラミックスと同時焼成により形成されたものである。第１の内部電極層および第２の内部電極層からなり、圧電体層と交互に積層されて圧電体層を上下から挟んでいる。内部電極層を形成する材料としては、種々の金属材料を用いることができる。例えば、低温焼成が可能な銀や銀－パラジウムを主成分とする導体、あるいは銅、白金などを含む導体を用いることができるが、これらにセラミック成分やガラス成分を含有させてもよい。なお、銀とパラジウムとからなる金属成分と、圧電体層を構成するセラミック成分とを含有した材料で内部電極層を構成した場合、圧電体層と内部電極層との熱膨張差による応力を低減することができるので、積層不良のない圧電素子２３を得ることができる。 Further, the internal electrode layer constituting the piezoelectric element 23 is formed by simultaneous firing with the ceramic forming the piezoelectric layer. It consists of a first internal electrode layer and a second internal electrode layer, and is alternately laminated with piezoelectric layers to sandwich the piezoelectric layers from above and below. As a material for forming the internal electrode layer, various metal materials can be used. For example, a conductor mainly composed of silver or silver-palladium that can be fired at a low temperature, or a conductor containing copper, platinum, or the like can be used, but these may contain a ceramic component or a glass component. When the internal electrode layer is made of a material containing a metal component composed of silver and palladium and a ceramic component that constitutes the piezoelectric layer, the stress due to the thermal expansion difference between the piezoelectric layer and the internal electrode layer is reduced. Therefore, it is possible to obtain the piezoelectric element 23 having no stacking failure.
　圧電素子２３としては、例えば上面側および下面側の主面が長方形状または正方形状といった多角形の形状、あるいは円形または楕円形といった形状をなしている板状体とすることができる。このような圧電素子２３および振動板２２と枠体２１を用いることにより、音響発生器１２を薄型にすることができる。 As the piezoelectric element 23, for example, a main body on the upper surface side and the lower surface side may be a plate-like body having a polygonal shape such as a rectangular shape or a square shape, or a circular shape or an elliptical shape. By using such a piezoelectric element 23, the diaphragm 22 and the frame body 21, the acoustic generator 12 can be made thin.
　圧電素子２３は例えば圧電体層が１層のモノモルフ構造であって構わないが、圧電体層が２層以上でバイモルフ構造とするのが好ましい。それにより、薄型化に貢献するとともに、少ないエネルギーで効率よく振動板２２を振動できる。また、ある瞬間に加えられる電界による変位の向きが、厚み方向における一方側と他方側とで逆転するように分極されているバイモルフ構造においては、圧電素子２３自体が屈曲振動することにより、振動板２２との接合面での機械的損失を低減できるため、音圧の向上に寄与することができる。 The piezoelectric element 23 may have, for example, a monomorph structure with one piezoelectric layer, but preferably has a bimorph structure with two or more piezoelectric layers. Thereby, while contributing to thickness reduction, the diaphragm 22 can be efficiently vibrated with less energy. Further, in a bimorph structure in which the direction of displacement due to an electric field applied at a certain moment is reversed between the one side and the other side in the thickness direction, the piezoelectric element 23 itself undergoes flexural vibration, whereby the diaphragm Since the mechanical loss at the joint surface with 22 can be reduced, the sound pressure can be improved.
　振動板２２としては、樹脂や金属等の種々の材料を用いて形成することができる。例えば、厚さ１０～２００μｍのポリエチレン、ポリイミド等の樹脂フィルムで振動板２２を構成することができる。 The diaphragm 22 can be formed using various materials such as resin and metal. For example, the diaphragm 22 can be made of a resin film such as polyethylene or polyimide having a thickness of 10 to 200 μm.
　圧電素子２３はエポキシ系樹脂、アクリル系樹脂、ゴム系樹脂等の接着剤により振動板２２に接合されており、圧電素子２３の振動によって振動板２２が振動する。例えば、圧電素子２３の表面電極に配線部材（図示せず）が接続され、この配線部材を介して圧電素子２３に電気信号が入力されて圧電素子２３が面内方向（振動板２２の主面に平行な方向）に伸長した場合、振動板２２自体は電気信号による変位を生じないため、結果的に振動板２２は圧電素子２３側へ凸となるように屈曲する。次に、この状態で電気信号の正負極を逆転すると圧電素子２３が面内方向に収縮し、振動板２２自体は電気信号による変位を生じないため、結果的に振動板２２は圧電素子２３側へ凹となるように屈曲する。すなわち、圧電素子２３に交流信号を与えることにより、圧電素子２３を面内方向に伸縮させて、振動板２２に屈曲振動を与えることができる。 The piezoelectric element 23 is bonded to the diaphragm 22 with an adhesive such as an epoxy resin, an acrylic resin, or a rubber resin, and the diaphragm 22 vibrates due to the vibration of the piezoelectric element 23. For example, a wiring member (not shown) is connected to the surface electrode of the piezoelectric element 23, and an electric signal is input to the piezoelectric element 23 through this wiring member, so that the piezoelectric element 23 is in the in-plane direction (the main surface of the diaphragm 22 When the diaphragm 22 is extended in a direction parallel to the piezoelectric element 23, the diaphragm 22 itself is not displaced by an electric signal. As a result, the diaphragm 22 is bent so as to be convex toward the piezoelectric element 23 side. Next, when the positive and negative electrodes of the electrical signal are reversed in this state, the piezoelectric element 23 contracts in the in-plane direction, and the vibration plate 22 itself is not displaced by the electric signal. Bend to be concave. That is, by applying an AC signal to the piezoelectric element 23, the piezoelectric element 23 can be expanded and contracted in the in-plane direction, and bending vibration can be applied to the diaphragm 22.
　また、振動板２２の主面の外周部を支持するように枠体２１が設けられている。枠体２１としては、例えば内周形状および外周形状が矩形である部材を用いることができる。図１および図２に示す例では、枠体２１は振動板２２の両主面を挟み込むように設けられている。 Further, the frame body 21 is provided so as to support the outer peripheral portion of the main surface of the diaphragm 22. As the frame body 21, for example, a member whose inner peripheral shape and outer peripheral shape are rectangular can be used. In the example shown in FIGS. 1 and 2, the frame body 21 is provided so as to sandwich both main surfaces of the diaphragm 22.
　枠体２１の厚さとしては、例えば１００～５０００μｍのものを採用することができる。また、枠体２１の材質としては、例えばガラスや金属や樹脂など種々の材料を用いることができる。ガラスや金属の場合は剛性が高いため変形が小さく、音質が安定する。また、樹脂の場合は、ガラスや金属よりも剛性が小さく振動板２２の振動による変形を起こしやすいため、振動板２２の共振にスプリアス振動を誘発し易くなる。したがって、音圧特性において共振ピークが分散されピークやディップを低減でき、周波数特性を平坦化することができる。よって、音圧の平坦化による音質の向上を図ることができる。 The thickness of the frame body 21 may be 100 to 5000 μm, for example. Moreover, as a material of the frame 21, various materials, such as glass, a metal, and resin, can be used, for example. In the case of glass or metal, since the rigidity is high, the deformation is small and the sound quality is stable. In the case of resin, since it is less rigid than glass or metal and easily deforms due to vibration of the diaphragm 22, it is easy to induce spurious vibrations in the resonance of the diaphragm 22. Therefore, resonance peaks are dispersed in the sound pressure characteristics, and the peaks and dip can be reduced, and the frequency characteristics can be flattened. Therefore, the sound quality can be improved by flattening the sound pressure.
　なお、枠体２１は振動板２２を支持できるものであればよく、その形状等に特に制限はない。例えば、図１および図２に示すように、枠体２１の外周形状が長方形状であり、内周形状も長方形状である縦横比が１よりも大きい形状であると、共振の分散に寄与し、ピークやディップの低減に寄与することができる。ただし、正方形、平行四辺形、台形および正ｎ角形といった多角形であってもよく、円形や楕円形であってもよい。 Note that the frame body 21 is not particularly limited as long as it can support the diaphragm 22. For example, as shown in FIGS. 1 and 2, if the outer peripheral shape of the frame body 21 is a rectangular shape and the inner peripheral shape is also a rectangular shape and the aspect ratio is larger than 1, it contributes to the dispersion of resonance. , Can contribute to reduction of peaks and dip. However, it may be a polygon such as a square, a parallelogram, a trapezoid, and a regular n-gon, or a circle or an ellipse.
　また、図１および図２では圧電素子２３が１個の場合を例示しているが、圧電素子２３の個数を限定するものではない。 1 and 2 exemplify the case where there is one piezoelectric element 23, the number of piezoelectric elements 23 is not limited.
　さらに、枠体２１の枠内に圧電素子２３を被覆するように樹脂層２４が設けられてもよく、図１および図２においては、樹脂層２４が設けられている例を示している。 Further, a resin layer 24 may be provided in the frame of the frame body 21 so as to cover the piezoelectric element 23. FIGS. 1 and 2 show examples in which the resin layer 24 is provided.
　ところで、このような圧電スピーカー２を液晶テレビやパソコン等の音源として用いるにあたり、例えば液晶テレビの筐体の一部である板部材１１に放音孔としてスリット構造の開口部１０を設け、開口部１０（放音孔）より音を発する構成とされる。 By the way, when such a piezoelectric speaker 2 is used as a sound source for a liquid crystal television or a personal computer, for example, a plate member 11 which is a part of the casing of the liquid crystal television is provided with an opening 10 having a slit structure as a sound emitting hole. It is set as the structure which emits a sound from 10 (sound emitting hole).
　それゆえ、圧電スピーカー２は、開口部１０を有する板部材１１（壁面１）に対し、開口部１０と対向して取り付けられる。本実施形態の音響発生器１２においては、この圧電スピーカー２を板部材１１に取り付けるために保持部材３を備えている。保持部材３は、圧電スピーカー２の外周部を固定するとともに、一端が板部材１１の壁面１と接続されて、板部材１１の壁面１と圧電スピーカー２との間に囲まれた空間を形成している。なお、保持部材３は、圧電スピーカー２の外周部を固定する固定部３１と、空間の少なくとも一部が開放された開放部１３を形成するように構成された枠状部３２を備えている。ここで、図１においては、保持部材３が固定部３１と枠状部３２とから構成されている例を示しているが、これらを一体の構成としてもよい。 Therefore, the piezoelectric speaker 2 is attached to the plate member 11 (wall surface 1) having the opening 10 so as to face the opening 10. The acoustic generator 12 of the present embodiment includes a holding member 3 for attaching the piezoelectric speaker 2 to the plate member 11. The holding member 3 fixes the outer peripheral portion of the piezoelectric speaker 2 and one end is connected to the wall surface 1 of the plate member 11 to form a space surrounded by the wall surface 1 of the plate member 11 and the piezoelectric speaker 2. ing. The holding member 3 includes a fixed portion 31 that fixes the outer peripheral portion of the piezoelectric speaker 2 and a frame-shaped portion 32 that is configured to form an open portion 13 in which at least a part of the space is open. Here, in FIG. 1, an example in which the holding member 3 is configured by the fixed portion 31 and the frame-shaped portion 32 is illustrated, but these may be configured integrally.
　ここで、本実施形態の音響発生器１２において、枠状部３２は、空間の少なくとも一部が開放された開放部１３を形成するように構成されている。 Here, in the sound generator 12 of the present embodiment, the frame-shaped portion 32 is configured to form the open portion 13 in which at least a part of the space is open.
　音響発生器においては、開口部（放音孔）から発生される音の高音質化が求められている。従来、スリット構造の開口部が狭い場合に、放音孔から出る音において、高域の音が十分に再生出来ないという問題点があり、高域の音が十分に再生できることが求められていた。 Sound generators are required to improve the sound quality of sound generated from openings (sound holes). Conventionally, when the opening of the slit structure is narrow, there is a problem that the high frequency sound cannot be sufficiently reproduced in the sound emitted from the sound emission hole, and it has been demanded that the high frequency sound can be sufficiently reproduced. .
　これに対し、本実施形態によれば、音響発生器１２と開口部１０を有する板部材１１の壁面１の間での音の圧縮を抑制でき、音響発生器１２の最低共振周波数付近の低音が増強されず、周波数特性が平坦となる。これにより、高域の音の再生能力に優れた音響発生器１２とすることができる。 On the other hand, according to this embodiment, the compression of sound between the sound generator 12 and the wall surface 1 of the plate member 11 having the opening 10 can be suppressed, and a low sound near the lowest resonance frequency of the sound generator 12 can be suppressed. The frequency characteristics are flattened without being enhanced. Thereby, it can be set as the sound generator 12 excellent in the reproduction | regeneration capability of the high frequency sound.
　開放部１３とは、枠状部３２よりも内側の内部空間と枠状部３２よりも外側の外部空間とを接続する通路のようなものである。ここで、図２に示す音響発生器１２においては、開放部１３は、平面視で長方形状の枠状の部材の長辺に沿って切り欠かれたように設けられた形状になっているが、このような形状に限定されず、図３に示すように平面視で長方形状の枠状部３２の長辺の一部が切り欠かれたように設けられた形状であってもよく、図４に示すように平面視で長方形状の枠状部３２の長辺に設けられた貫通孔のような形状であってもよい。 The open portion 13 is a passage that connects an internal space inside the frame-shaped portion 32 and an external space outside the frame-shaped portion 32. Here, in the sound generator 12 shown in FIG. 2, the open portion 13 has a shape provided so as to be cut out along the long side of a rectangular frame-like member in plan view. The shape is not limited to such a shape, and may be a shape provided such that a part of the long side of the rectangular frame-shaped portion 32 is cut out in a plan view as shown in FIG. 4 may be a shape like a through-hole provided on the long side of the rectangular frame-shaped portion 32 in plan view.
　枠状部３２における開放部１３は、少なくとも板部材１１の開口部１０の大きさ以上の大きさであることが好ましい。ここでいう開放部１３が開口部１０よりも大きさが大きいとは、開放部１３および開口部１０をそれぞれ正面から見たときに、開放部１３のほうが開口部１０よりも開口面積が大きいことを意味する。これにより、圧電スピーカー２で発生された音の一部が、効率よく枠状部３２の開放部１３より放出され、高域の音の再生能力に優れた音響発生器とすることができる。 It is preferable that the open portion 13 in the frame-shaped portion 32 is at least the size of the opening 10 of the plate member 11. Here, the opening portion 13 is larger in size than the opening portion 10 when the opening portion 13 and the opening portion 10 are viewed from the front. The opening portion 13 has a larger opening area than the opening portion 10. Means. Thereby, a part of the sound generated by the piezoelectric speaker 2 is efficiently emitted from the open part 13 of the frame-shaped part 32, and an acoustic generator having excellent high-frequency sound reproduction capability can be obtained.
　また、枠状部３２の開放部１３は開口部１０よりも大きくすることが好ましいことから、図１および図２に示すように、開口部１０が長方形状のスリットであって、平面視で枠状部３２の外形が長方形状である場合、開放部１３は長方形状の長辺に沿って切り欠かれた形状とすることが好ましい。これにより、最低共振周波数付近の低音をより効果的に抑制できるとともに、短辺を切り欠く場合に比べて、音響発生器１２が大型化することを抑制することができる。 Moreover, since it is preferable that the opening part 13 of the frame-shaped part 32 is larger than the opening part 10, as shown in FIG.1 and FIG.2, the opening part 10 is a rectangular-shaped slit, Comprising: When the external shape of the shape part 32 is a rectangular shape, it is preferable that the open part 13 is made into the shape notched along the rectangular long side. As a result, it is possible to more effectively suppress the bass near the lowest resonance frequency, and it is possible to suppress an increase in the size of the sound generator 12 as compared with a case where the short side is cut away.
　なお、保持部材３における固定部３１および枠状部３２は、例えば、金属、ＡＢＳ、ポリスチレン、ポリプロピレン、ポリカーボネート、それらのアロイ系樹脂等の樹脂など種々の材料を用いることができる。 The fixing part 31 and the frame-like part 32 in the holding member 3 can be made of various materials such as metal, ABS, polystyrene, polypropylene, polycarbonate, and resins such as alloy resins thereof.
　開放部１３は、枠状部３２を切り欠くように加工して形成してもよく、また射出成形等により最初からそのような形状で形成してもよい。 The open portion 13 may be formed by processing so as to cut out the frame-shaped portion 32, or may be formed in such a shape from the beginning by injection molding or the like.
　図５は、開口部１０を有する板部材１１に、本実施形態の他の一例の音響発生器１６が取り付けられた音響発生装置４２を示し、（ａ）は平面図、（ｂ）はＡ－Ａ線断面図、（ｃ）はＢ－Ｂ線断面図である。 5A and 5B show a sound generator 42 in which the sound generator 16 of another example of the present embodiment is attached to the plate member 11 having the opening 10, wherein FIG. 5A is a plan view, and FIG. A cross-sectional view taken along line A, and (c) is a cross-sectional view taken along line BB.
　図５に示す音響発生装置４２は、図１に示す音響発生装置４１と比較して、音響発生器１６における保持部材３の一端側に周波数特性調整部材４が設けられている点で異なっている。ここで、保持部材３の一端側とは、保持部材３の固定部３１または枠状部３２における圧電スピーカー２の振動板２２と板部材１１の壁面１との間に位置する部分のことを意味する。 The sound generator 42 shown in FIG. 5 is different from the sound generator 41 shown in FIG. 1 in that a frequency characteristic adjusting member 4 is provided on one end side of the holding member 3 in the sound generator 16. . Here, the one end side of the holding member 3 means a portion located between the diaphragm 22 of the piezoelectric speaker 2 and the wall surface 1 of the plate member 11 in the fixing portion 31 or the frame-like portion 32 of the holding member 3. To do.
　保持部材３の一端側に周波数特性調整部材４を備えることにより、周波数特性調整部材４が音の反射を一部遮ることとなる。それにより、音響発生器１４と開口部１０を有する板部材１１の壁面１との間で生じる音の反射による周波数特性のピークディップをさらに低減することが出来る。 By providing the frequency characteristic adjusting member 4 on one end side of the holding member 3, the frequency characteristic adjusting member 4 partially blocks the reflection of sound. Thereby, the peak dip of the frequency characteristic due to sound reflection generated between the acoustic generator 14 and the wall surface 1 of the plate member 11 having the opening 10 can be further reduced.
　なお、周波数特性調整部材４は、圧電スピーカー２と開口部１０を有する板部材１１の壁面１との間で生じる音の反射の一部をさえぎればよく、その形状、大きさ、個数に特に制限はなく、音響発生器１６の周波数特性にあわせて適宜調整すればよい。例えば、図５においては、板部材１１の壁面１の面内方向に開口部１０を幅方向に横切るように延びた形状として、固定部３１に接続された周波数特性調整部材４を２つ設けた例を示しているが、例えば１つであってもよく、さらには枠状部３２に接続されていてもよい。また、圧電素子２３を複数個備える場合には、平面視でこれらの圧電素子２３の間に位置するように配置してもよい。 The frequency characteristic adjusting member 4 only needs to block a part of the sound reflection generated between the piezoelectric speaker 2 and the wall surface 1 of the plate member 11 having the opening 10, and the shape, size, and number thereof are particularly limited. There is no limitation, and it may be appropriately adjusted according to the frequency characteristics of the sound generator 16. For example, in FIG. 5, two frequency characteristic adjusting members 4 connected to the fixed portion 31 are provided in a shape extending in the in-plane direction of the wall surface 1 of the plate member 11 so as to cross the opening 10 in the width direction. Although an example is shown, it may be one, for example, and may be further connected to the frame part 32. Further, when a plurality of piezoelectric elements 23 are provided, they may be arranged so as to be positioned between these piezoelectric elements 23 in plan view.
　なお、周波数特性調整部材４としては、圧電スピーカー２と開口部１０を有する板部材１１の壁面１の間で生じる音の反射の一部をさえぎることができる材質から構成すればよく、例えば、固定部３１と同じ材質とすることができる。 The frequency characteristic adjusting member 4 may be made of a material that can block a part of sound reflection generated between the piezoelectric speaker 2 and the wall surface 1 of the plate member 11 having the opening 10. The same material as the part 31 can be used.
　図６は、開口部１０を有する板部材１１に、本実施形態のさらに他の一例の音響発生器１７が取り付けられた音響発生装置４３を示し、（ａ）は平面図、（ｂ）はＡ－Ａ線断面図、（ｃ）はＢ－Ｂ線断面図である。 FIG. 6 shows a sound generator 43 in which the sound generator 17 of still another example of the present embodiment is attached to the plate member 11 having the opening 10, wherein (a) is a plan view and (b) is A. A cross-sectional view taken along line -A, and (c) is a cross-sectional view taken along line BB.
　図６に示す音響発生装置４３は、図５に示す音響発生装置４２と比較して、音響発生器１２における保持部材３の一端側に吸音材５が設けられている点で異なっている。ここでいう保持部材３の一端側も、保持部材３の固定部３１または枠状部３２における圧電スピーカー２の振動板２２と板部材１１の壁面１との間に位置する部分のことを意味する。 6 is different from the sound generator 42 shown in FIG. 5 in that a sound absorbing material 5 is provided on one end side of the holding member 3 in the sound generator 12. The one end side of the holding member 3 here also means a portion located between the diaphragm 22 of the piezoelectric speaker 2 and the wall surface 1 of the plate member 11 in the fixed portion 31 or the frame-like portion 32 of the holding member 3. .
　保持部材３の一端側に吸音材５を備えることにより、周波数特性のピークディップに関係している反射音を吸音材５で吸収することができ、周波数特性をさらに平坦にすることが出来る。 By providing the sound absorbing material 5 on one end side of the holding member 3, the reflected sound related to the peak dip of the frequency characteristic can be absorbed by the sound absorbing material 5, and the frequency characteristic can be further flattened.
　なお、吸音材５は、音響発生器１７と開口部１０を有する板部材１１の壁面１との間で生じる音の反射の一部を吸収できればよく、その形状、大きさ、個数に特に制限はなく、音響発生器１２の周波数特性にあわせて適宜調整すればよい。例えば、図６においては、枠状部３２の一辺側の両端に２つ設けた例を示しているが、例えば、一端だけに設けるほか、全ての端に４つ設けてもよい。さらには、枠状部３２の内面に沿って設けてもよい。 The sound absorbing material 5 only needs to be able to absorb a part of sound reflection generated between the sound generator 17 and the wall surface 1 of the plate member 11 having the opening 10, and the shape, size, and number thereof are not particularly limited. However, it may be adjusted appropriately according to the frequency characteristics of the sound generator 12. For example, FIG. 6 shows an example in which two frames are provided at both ends on one side of the frame-like portion 32. For example, four frames may be provided at all ends instead of only at one end. Furthermore, it may be provided along the inner surface of the frame-shaped portion 32.
　なお、吸音材５としては、音響発生器１５と開口部１０を有する板部材１１の壁面１との間で生じる音の反射の一部を吸収ものであればよく、例えば、発泡ウレタン、発泡ゴム、綿状の繊維等を用いることができる。 Note that the sound absorbing material 5 may be any material that absorbs part of the sound reflection generated between the sound generator 15 and the wall surface 1 of the plate member 11 having the opening 10. For example, urethane foam, foam rubber Cotton fiber or the like can be used.
　図７は、開口部１０を有する板部材１１に、本実施形態のさらに他の一例の音響発生器１８が取り付けられた音響発生装置４４を示し、（ａ）は平面図、（ｂ）はＡ－Ａ線断面図、（ｃ）はＢ－Ｂ線断面図である。 FIG. 7 shows a sound generator 44 in which the sound generator 18 of still another example of the present embodiment is attached to the plate member 11 having the opening 10, (a) is a plan view, and (b) is A A cross-sectional view taken along line -A, and (c) is a cross-sectional view taken along line BB.
　図７に示す音響発生装置４４は、図６に示す音響発生装置４３と比較して、音響発生器１５の開口部１０を有する壁面１への取り付け位置がずれている点で異なっている。 7 differs from the sound generator 43 shown in FIG. 6 in that the mounting position of the sound generator 15 on the wall surface 1 having the opening 10 is shifted.
　すなわち、図７に示す音響発生装置４４は、音響発生器１５が、壁面１の開口部１０の中心と、圧電スピーカー２の中心とを、ずらして取り付けられており、それにより、音響発生器１５と板部材１１の壁面１との間で生じる反射音の周波数特性にバラつきが生じるため、周波数特性をより平坦とすることができる。 That is, in the sound generator 44 shown in FIG. 7, the sound generator 15 is attached so that the center of the opening 10 of the wall surface 1 and the center of the piezoelectric speaker 2 are shifted from each other. Since the frequency characteristics of the reflected sound generated between the wall member 1 and the wall surface 1 of the plate member 11 vary, the frequency characteristics can be made flatter.
　なお、音響発生器１８を、板部材１１の開口部１０の中心と、圧電スピーカー２の中心とをずらして取り付けるにあたっては、平面透視した際に、開口部１０が枠状部３２の内側の範囲内でずれるようにすることが好ましい。 When mounting the acoustic generator 18 by shifting the center of the opening 10 of the plate member 11 from the center of the piezoelectric speaker 2, the opening 10 is in a range inside the frame-shaped part 32 when viewed through a plane. It is preferable to make it shift within.
　平面視で枠状部３２の外形が長方形状である場合、開口部１０が枠状部３２の内側の範囲内でずれるように取り付けるにあたっては、枠状部３２の対向する長辺と開口部１０との距離が異なるように取り付けることが好ましい。これにより、枠状部３２の開放部１３と板部材１１の開口部１０との距離が異なることで、板部材１１の壁面１と開口部１０の距離に依存する共振周波数が変わり、共振周波数の集中による顕著なピークディップがなくなるため、周波数特性をより平坦とすることができる。 When the outer shape of the frame-like portion 32 is rectangular in plan view, the attachment of the opening 10 so that the opening 10 is displaced within the range inside the frame-like portion 32, and the opening 10 It is preferable to attach so that the distance between and is different. As a result, the distance between the open portion 13 of the frame-shaped portion 32 and the opening 10 of the plate member 11 is different, so that the resonance frequency depending on the distance between the wall surface 1 of the plate member 11 and the opening 10 is changed. Since there is no significant peak dip due to concentration, the frequency characteristics can be made flatter.
　図８は、本実施形態の電子機器の一例を示すブロック図である。 FIG. 8 is a block diagram illustrating an example of the electronic apparatus of the present embodiment.
　図８に示すように、本例の電子機器５０は、音響発生器１２と、音響発生器１２に接続された電子回路６０と、電子回路６０および音響発生器１２を収容する筐体７０とを備え、音響発生器１２から音響を発生させる機能を有する。なお、図示しないが、電子機器５０は、筐体７０の一部が開口部を有する板部材となっていて、この筐体７０の一部である開口部を有する板部材に対し、当該開口部と対向するように音響発生器が取り付けられている。 As shown in FIG. 8, the electronic device 50 of this example includes an acoustic generator 12, an electronic circuit 60 connected to the acoustic generator 12, and a housing 70 that houses the electronic circuit 60 and the acoustic generator 12. And having a function of generating sound from the sound generator 12. Although not illustrated, the electronic device 50 includes a plate member in which a part of the housing 70 has an opening, and the opening is formed with respect to the plate member having an opening that is a part of the housing 70. A sound generator is attached so as to oppose.
　電子回路６０は、たとえば、コントローラ５０ａと、送受信部５０ｂと、キー入力部５０ｃと、マイク入力部５０ｄとから構成される。電子回路６０は、音響発生器１２に接続されており、音響発生器１２へ音声信号を出力する機能を有している。音響発生器１２は電子回路６０から入力された音声信号に基づいて音響を発生させる。 The electronic circuit 60 includes, for example, a controller 50a, a transmission / reception unit 50b, a key input unit 50c, and a microphone input unit 50d. The electronic circuit 60 is connected to the sound generator 12 and has a function of outputting an audio signal to the sound generator 12. The sound generator 12 generates sound based on the sound signal input from the electronic circuit 60.
　また、電子機器５０は、表示部５０ｅと、アンテナ５０ｆとを備え、上述した各デバイスを含めてこれらが筐体７０に収容されている。なお、図８では、１つの筐体７０にコントローラ５０ａをはじめとする各デバイスがすべて収容されている状態をあらわしているが、各デバイスの収容形態を限定するものではない。本実施形態では、少なくとも電子回路６０と音響発生器１２とが、１つの筐体７０に収容されていればよい。 Further, the electronic device 50 includes a display unit 50e and an antenna 50f, and these are housed in the housing 70 including the above-described devices. Although FIG. 8 shows a state in which each device including the controller 50a is accommodated in one casing 70, the accommodation form of each device is not limited. In the present embodiment, it is only necessary that at least the electronic circuit 60 and the sound generator 12 are accommodated in one housing 70.
　コントローラ５０ａは、電子機器５０の制御部である。送受信部５０ｂは、コントローラ５０ａの制御に基づき、アンテナ５０ｆを介してデータの送受信などを行う。キー入力部５０ｃは、電子機器５０の入力デバイスであり、操作者によるキー入力操作を受け付ける。マイク入力部５０ｄは、同じく電子機器５０の入力デバイスであり、操作者による音声入力操作などを受け付ける。表示部５０ｅは、電子機器５０の表示出力デバイスであり、コントローラ５０ａの制御に基づき、表示情報の出力を行う。 The controller 50 a is a control unit of the electronic device 50. The transmission / reception unit 50b transmits / receives data via the antenna 50f based on the control of the controller 50a. The key input unit 50c is an input device of the electronic device 50 and accepts a key input operation by an operator. The microphone input unit 50d is also an input device of the electronic device 50, and accepts a voice input operation by an operator. The display unit 50e is a display output device of the electronic device 50, and outputs display information based on the control of the controller 50a.
　そして、音響発生器１２は、電子機器５０における音響出力デバイスとして動作する。なお、音響発生器１２は、電子回路６０のコントローラ５０ａに接続されており、コントローラ５０ａによって制御された電圧の印加を受けて音響を発することとなる。 The acoustic generator 12 operates as an acoustic output device in the electronic device 50. The sound generator 12 is connected to the controller 50a of the electronic circuit 60, and emits sound upon application of a voltage controlled by the controller 50a.
　なお、図８では、電子機器５０が携帯用端末装置であるものとして説明を行ったが、電子機器５０の種別を問うものではなく、音響を発する機能を有する様々な民生機器に適用されてよい。たとえば、薄型テレビやカーオーディオ機器は無論のこと、音響を発する機能を有する製品、例を挙げれば、掃除機や洗濯機、冷蔵庫、電子レンジなどといった種々の製品に用いられてよい。 In FIG. 8, the electronic device 50 is described as a portable terminal device. However, the electronic device 50 is not limited to the type of the electronic device 50, and may be applied to various consumer devices having a function of emitting sound. . For example, flat-screen televisions and car audio devices can of course be used for products having a function of generating sound, for example, various products such as vacuum cleaners, washing machines, refrigerators, microwave ovens, and the like.
　上述した本実施形態の電子機器５０は、高域の音の再生能力に優れた音響発生器１２を備えていることから、高域の音の再生能力に優れた電子機器５０とすることができる。 Since the electronic device 50 according to the present embodiment described above includes the sound generator 12 having an excellent high frequency sound reproduction capability, the electronic device 50 having an excellent high frequency sound reproduction capability can be obtained. .
　本実施形態の音響発生装置の具体例について説明する。 A specific example of the sound generator of this embodiment will be described.
　音響発生器を取り付ける板部材として、長さが２９７ｍｍ、幅が２１０ｍｍ、厚みが４ｍｍの長尺板状で、材質がＡＢＳ樹脂製のものを用意した。なお、開口部は、長さが２８ｍｍ、幅が３ｍｍ、厚みが４ｍｍとした。 As a plate member to which the sound generator is attached, a long plate shape having a length of 297 mm, a width of 210 mm, and a thickness of 4 mm and a material made of ABS resin was prepared. The opening was 28 mm in length, 3 mm in width, and 4 mm in thickness.
　この開口部に対向するように音響発生器を取り付けた。音響発生器の一部を構成する圧電スピーカーは、長さが３０ｍｍ、幅が１０ｍｍ、厚みが１５μｍとし、材質がポリエーテルイミドの振動板に、長さが７ｍｍ、幅が６ｍｍ、厚みが０．１９ｍｍとし、圧電材料からなる圧電素子を取り付け、振動板の主面に、長さが３０ｍｍ、幅が１０ｍｍ、厚みが１ｍｍのロの字型とし、ロの字の幅を１ｍｍとし、材質がステンレス鋼からなる枠体を取り付けた。圧電素子は、熱硬化型エポキシ樹脂にて枠体内に埋設した。 A sound generator was attached so as to face this opening. The piezoelectric speaker constituting a part of the sound generator has a length of 30 mm, a width of 10 mm, a thickness of 15 μm, a material made of polyetherimide, a length of 7 mm, a width of 6 mm, and a thickness of 0.1 mm. 19 mm, a piezoelectric element made of a piezoelectric material is attached, and the main surface of the diaphragm is 30 mm in length, 10 mm in width, 1 mm in thickness with a square shape, the width of the square shape is 1 mm, and the material is stainless steel A frame made of steel was attached. The piezoelectric element was embedded in the frame with a thermosetting epoxy resin.
　この圧電スピーカーに、長さが３４ｍｍ、幅が１４ｍｍ、厚みが３ｍｍのコの字型とし、コの字の幅を３ｍｍとし、材質をＡＢＳとした保持部材３を、接着剤で貼り合わせて音響発生器を作製し、これを開口部と対向するように板部材に接着剤で貼り合わせて図１および図２に示すような形態の第１の音響発生装置とした。 The piezoelectric speaker is formed into a U-shape having a length of 34 mm, a width of 14 mm, and a thickness of 3 mm, a U-shaped width of 3 mm, and a material made of ABS. A generator was produced, and this was bonded to the plate member with an adhesive so as to face the opening, thereby forming a first sound generator of the form as shown in FIGS.
　また、上記第１の音響発生装置に、周波数特性調整材４として、長さが３４ｍｍ、幅が３ｍｍ、厚みが１ｍｍの板状で、材質をＡＢＳとしたものを２枚、壁面の面内方向に開口部を横切るように延びた形状として、保持部材に取り付けて図５に示すような形態の第２の音響発生装置を作製した。 Further, in the first sound generator, the frequency characteristic adjusting material 4 is a plate having a length of 34 mm, a width of 3 mm, and a thickness of 1 mm, and two materials made of ABS, in-plane direction of the wall surface As shown in FIG. 5, a second sound generation device having a configuration as shown in FIG. 5 was produced by attaching to a holding member as a shape extending across the opening.
　また、上記第２の音響発生装置に、吸音材として、長さが４ｍｍ、幅が４ｍｍ、厚みが１ｍｍのものを２個、保持部材の一辺側の両端に配置して図６に示すような形態の第３の音響発生装置を作製した。なお、吸音材の材質は発泡ウレタンとした。 Further, in the second sound generator, two sound absorbing materials having a length of 4 mm, a width of 4 mm, and a thickness of 1 mm are arranged at both ends on one side of the holding member as shown in FIG. A third acoustic generator of the form was produced. The material of the sound absorbing material was urethane foam.
　さらに、第３の音響発生装置において、保持部材と音響発生器を壁面の開口部の中心位置から長辺方向に２ｍｍずらして配置して図７に示すような形態の第４の音響発生装置を作製した。 Furthermore, in the third sound generator, the holding member and the sound generator are arranged with a shift of 2 mm in the long side direction from the center position of the opening of the wall surface, and the fourth sound generator having a form as shown in FIG. Produced.
　なお、比較例として、上記圧電スピーカーに、長さが３４ｍｍ、幅が１４ｍｍ、厚みが３ｍｍのロの字状の保持部材を貼り合わせて、比較例の音響発生装置を作製した。 As a comparative example, a square-shaped holding member having a length of 34 mm, a width of 14 mm, and a thickness of 3 mm was bonded to the above piezoelectric speaker to produce a sound generator of a comparative example.
　これらの音響発生装置について、圧電素子に１ｋＨｚの周波数で実効値±７Ｖｒｍｓとなる電圧で、１ｋＨｚから１００ｋＨｚまでの周波数掃引試験を行い、周波数特性を測定した。 For these acoustic generators, a frequency sweep test from 1 kHz to 100 kHz was performed on the piezoelectric element at a voltage of an effective value ± 7 Vrms at a frequency of 1 kHz, and the frequency characteristics were measured.
　比較例の音響発生装置の結果を図９に、第１の音響発生装置の結果を図１０に、第２の音響発生装置の結果を図１１に、第３の音響発生装置の結果を図１２に、第４の音響発生装置の結果を図１３にそれぞれ示す。 The result of the sound generator of the comparative example is shown in FIG. 9, the result of the first sound generator is shown in FIG. 10, the result of the second sound generator is shown in FIG. 11, and the result of the third sound generator is shown in FIG. FIG. 13 shows the results of the fourth sound generator.
　以上の結果より、図１０～図１３に示した本実施形態の音響発生装置は、比較例である図９に示した音響発生装置に比較して、１０ｋＨｚ付近のピークを低減できており、高域の音の再生能力に優れた音響発生装置であることが確認できた。 From the above results, the sound generator of this embodiment shown in FIG. 10 to FIG. 13 can reduce the peak around 10 kHz compared with the sound generator shown in FIG. It was confirmed that the sound generator was excellent in sound reproduction ability.
１　壁面
２　圧電スピーカー
３　保持部材
４　周波数特性調整部材
５　吸音材
１０　開口部
１１　板部材
１２、１４、１５、１６、１７、１８　音響発生器
１３　開放部
４１、４２、４３、４４　音響発生装置
５０　電子機器
６０　電子回路
７０　筺体 DESCRIPTION OF SYMBOLS 1 Wall surface 2 Piezoelectric speaker 3 Holding member 4 Frequency characteristic adjustment member 5 Sound absorbing material 10 Opening part 11 Plate member 12, 14, 15, 16, 17, 18 Sound generator 13 Opening part 41, 42, 43, 44 Sound generating apparatus 50 Electronic device 60 Electronic circuit 70 Housing

Claims (6)

  1. 　開口部を有する板部材に対し、前記開口部と対向して取り付けられる音響発生器であって、圧電素子、該圧電素子が取り付けられた振動板および該振動板の少なくとも一方の主面の外周部を支持する枠体を有する圧電スピーカーと、該圧電スピーカーの外周部を固定するとともに、一端が前記板部材と接続されて前記板部材と前記圧電スピーカーとの間に囲まれた空間を形成する保持部材と、を備えてなり、該保持部材は、前記空間の少なくとも一部が開放された開放部を形成するように構成された枠状部を備えている音響発生器。 An acoustic generator attached to a plate member having an opening so as to face the opening, the piezoelectric element, a diaphragm to which the piezoelectric element is attached, and an outer peripheral portion of at least one main surface of the diaphragm A piezoelectric speaker having a frame that supports the piezoelectric speaker, and an outer peripheral portion of the piezoelectric speaker, and a holding member that is connected to the plate member to form a space surrounded by the plate member and the piezoelectric speaker. And a holding member, wherein the holding member includes a frame-shaped portion configured to form an open portion in which at least a part of the space is open.
  2. 　前記保持部材の一端側に、周波数特性調整部材が設けられている請求項１に記載の音響発生器。 The sound generator according to claim 1, wherein a frequency characteristic adjusting member is provided on one end side of the holding member.
  3. 　前記保持部材の一端側に、吸音材が設けられている請求項１または請求項２に記載の音響発生器。 The sound generator according to claim 1 or 2, wherein a sound absorbing material is provided on one end side of the holding member.
  4. 　前記開口部を有する板部材と、前記開口部と対向して取り付けられた請求項１乃至請求項３のうちいずれかに記載の音響発生器とを備えている音響発生装置。 A sound generator comprising: a plate member having the opening; and the sound generator according to any one of claims 1 to 3 attached to face the opening.
  5. 　前記開口部の中心と前記圧電スピーカーの中心とがずれて取り付けられている請求項４に記載の音響発生装置。 The sound generator according to claim 4, wherein the center of the opening and the center of the piezoelectric speaker are attached to be shifted.
  6. 　請求項１乃至請求項３のうちのいずれかに記載の音響発生器と、該音響発生器に接続された電子回路と、該電子回路および前記音響発生器を収容する筐体とを備える電子機器。 An electronic apparatus comprising: the sound generator according to claim 1; an electronic circuit connected to the sound generator; and a housing that houses the electronic circuit and the sound generator. .
PCT/JP2016/058072 2015-08-20 2016-03-15 Sound generator, sound generation device and electronic apparatus WO2017029828A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2017535251A JPWO2017029828A1 (en) 2015-08-20 2016-03-15 Sound generator, sound generator and electronic device

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2015-162974 2015-08-20
JP2015162974 2015-08-20

Publications (1)

Publication Number Publication Date
WO2017029828A1 true WO2017029828A1 (en) 2017-02-23

Family

ID=58051518

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2016/058072 WO2017029828A1 (en) 2015-08-20 2016-03-15 Sound generator, sound generation device and electronic apparatus

Country Status (2)

Country Link
JP (1) JPWO2017029828A1 (en)
WO (1) WO2017029828A1 (en)

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH08107594A (en) * 1994-10-04 1996-04-23 Matsushita Electric Ind Co Ltd Loudspeaker device
JPH10313499A (en) * 1997-05-12 1998-11-24 Taiyo Yuden Co Ltd Piezoelectric acoustic device
WO2014024528A1 (en) * 2012-08-10 2014-02-13 京セラ株式会社 Sound generator, sound generation device, and electronic device

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH08107594A (en) * 1994-10-04 1996-04-23 Matsushita Electric Ind Co Ltd Loudspeaker device
JPH10313499A (en) * 1997-05-12 1998-11-24 Taiyo Yuden Co Ltd Piezoelectric acoustic device
WO2014024528A1 (en) * 2012-08-10 2014-02-13 京セラ株式会社 Sound generator, sound generation device, and electronic device

Also Published As

Publication number Publication date
JPWO2017029828A1 (en) 2018-05-10

Similar Documents

Publication Publication Date Title
JP5860559B1 (en) Electroacoustic transducer
JP6053827B2 (en) SOUND GENERATOR AND ELECTRONIC DEVICE USING THE SAME
JP5677639B2 (en) SOUND GENERATOR, SOUND GENERATOR, AND ELECTRONIC DEVICE
JP6047575B2 (en) SOUND GENERATOR, SOUND GENERATOR, AND ELECTRONIC DEVICE
US9497550B2 (en) Vibration device, sound generator, speaker system, and electronic device
KR101538977B1 (en) Acoustic generator, acoustic generation device, and electronic device
JP5676016B2 (en) Vibration device, sound generator, speaker system, electronic equipment
JP5977473B1 (en) Vibration transmission structure and piezoelectric speaker
JP2015185819A (en) Driver of bimorph piezoelectric element and portable terminal including the same, acoustic generator, acoustic generation device, electronic apparatus
JPWO2016103826A1 (en) SOUND GENERATOR, SOUND GENERATOR, AND ELECTRONIC DEVICE
WO2017029828A1 (en) Sound generator, sound generation device and electronic apparatus
JP2014123812A (en) Sound generator, sound generating system, and electronic apparatus
JP2012216905A (en) Display device and electronic apparatus
JP2015180053A (en) Acoustic generator, acoustic generation device, electronic apparatus, and portable terminal
JP2016184786A (en) Acoustic generation device and electronic apparatus including the same
JP6408432B2 (en) SOUND GENERATOR AND ELECTRONIC DEVICE HAVING THE SAME
JP2014127748A (en) Acoustic generator, acoustic generating device, and electronic apparatus
JP5488266B2 (en) Oscillator
JP2018074322A (en) Acoustic generator, acoustic generation device comprising the same, and electronic apparatus
JP2017118424A (en) Acoustic generator, acoustic generation device and electronic apparatus
JP2015177422A (en) Acoustic generator, acoustic generation device, electronic apparatus, and portable terminal
JP2015149604A (en) Speaker, electronic apparatus, and portable terminal
WO2014091813A1 (en) Acoustic generator, acoustic generation device, and electronic device
JP2012029086A (en) Electronic apparatus
WO2014083902A1 (en) Acoustic generator and electronic apparatus using same

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 16836820

Country of ref document: EP

Kind code of ref document: A1

ENP Entry into the national phase

Ref document number: 2017535251

Country of ref document: JP

Kind code of ref document: A

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 16836820

Country of ref document: EP

Kind code of ref document: A1