阅读说明：本技术 压电音响部件 (Piezoelectricity sound part ) 是由 田村雅英 砂原忠男 滨田纮司 铃木隆太 于 2018-03-29 设计创作，主要内容包括：本发明提供一种即使在噪音大的场所,也能够听见多个音阶的声音的压电音响部件。压电发音元件(11)由金属制的振动板(12)以及设置于振动板(12)的至少一面上的压电元件(15)构成。振动板(12)的非固定部具有彼此相对的一对长边(13A)和长度比该长边(13A)短且彼此相对的一对短边(13B),在一对长边(13A)中具有向相互靠近的方向凸出的一对凹部(13C)。压电元件(15)设置于振动板(12)的一对凹部(13C)之间的区域上,振动板(12)的非固定部(13)以及压电元件(15)各自的轮廓形状被设定成相对于将一对短边(13B)一分为二的第一假想线(PL1)对称且相对于将一对长边(13A)一分为二的第二假想线(PL2)对称。(Even if the present invention provides a kind of place big in noise, the piezoelectricity sound part of the sound of multiple scales can be also heard.Piezoelectricity pronunciation component (11) is made of metal oscillating plate (12) and the piezoelectric element (15) being set in at least one side of oscillating plate (12).A pair of short edges (13B) that the on-fixed portion of oscillating plate (12) has a pair of of long side (13A) and length relative to each other shorter and relative to each other than the long side (13A), has a pair of of the recess portion (13C) protruded to direction close to each other in a pair of of long side (13A).Piezoelectric element (15) is set on the region between a pair of of recess portion (13C) of oscillating plate (12), and the on-fixed portion (13) of oscillating plate (12) and piezoelectric element (15) respective chamfered shape are configured to symmetrical relative to the first imaginary line (PL1) that a pair of short edges (13B) is divided into two and symmetrical relative to the second imaginary line (PL2) that a pair of of long side (13A) is divided into two.)

1. a kind of piezoelectricity sound part, equipped with piezoelectricity pronunciation component and shell,

The piezoelectricity pronunciation component by metal oscillating plate and be set in at least one side of the oscillating plate piezoelectricity member Part is constituted,

The shell is configured to substantially fix the peripheral part of the oscillating plate of the piezoelectricity pronunciation component, and The first space and second space are formed in the two sides of the piezoelectricity pronunciation component, is formed in the wall portion opposite with first space There is 1 or more louver, resonator constituted by the louver of the volume in first space and described 1 or more, wherein

Non-fixed portions positioned at the inside of the peripheral part of the oscillating plate have a pair of of long side and length relative to each other A pair of short edges shorter than the long side and relative to each other has a pair protruded in a direction close to each other in the pair of long side Recess portion,

The piezoelectric element is set on the region between the pair of recess portion of the non-fixed portions of the oscillating plate,

The oscillating plate and the respective chamfered shape of the piezoelectric element are set to Two the first imaginary line is symmetrical and symmetrical relative to the second imaginary line that the pair of long side is divided into two,

The ratio between the length L1 of the long side of the non-fixed portions of the oscillating plate and the length W1 of the short side L1/W1 quilt It is set as falling into 1.25~1.75 range,

The resonator be constituted such that when as input signal and when input sine wave signal 1 subresonance frequency, 3 times altogether The acoustic pressure of intermediate frequency between vibration frequency and the 1 subresonance frequency and the 3 subresonance frequency respectively 80dB with On.

2. piezoelectricity sound part as described in claim 1, which is characterized in that the resonator is constituted such that the centre The acoustic pressure of frequency is more than the acoustic pressure of the 1 subresonance frequency and the acoustic pressure of the 3 subresonance frequency.

3. piezoelectricity sound part as described in claim 1, which is characterized in that the resonator is constructed so as to be total to for described 1 time The minimum between minimum acoustic pressure and the intermediate frequency and the 3 subresonance frequency between vibration frequency and the intermediate frequency Acoustic pressure is respectively in 80dB or more.

4. piezoelectricity sound part as described in claim 1, which is characterized in that the shell, which has, to be formed and the oscillating plate The opening portion of the identical shape of chamfered shape in the on-fixed portion, and have and the peripheral part of the oscillating plate is fixed Pronunciation component holder.

5. piezoelectricity sound part according to any one of claims 1 to 4, which is characterized in that the pair of short side is at both ends Portion has to the inclined a pair of angled portion in direction close to each other.

6. the piezoelectricity sound part as described in any one of claims 1 to 5, which is characterized in that at the back side of the oscillating plate It is provided with the piezoelectric element.

7. such as piezoelectricity sound part described in any one of claims 1 to 6, which is characterized in that the oscillating plate it is described non- The recess portion of fixed part is configured to the parallel lines portion extended parallel to first imaginary line and from described The both ends in parallel lines portion be separated from each other and towards the remainder of the corresponding long side extend a pair of angled straight line portion,

The profile of the piezoelectric element have a pair of of straight line portion along a pair of respective parallel lines portion of recess portion, with And with the region folded by a pair of angled straight line portion opposite with the direction of second imaginary line of the pair of recess portion extension The curved bending section of mode of introversive the pair of short side protrusion.

8. such as piezoelectricity sound part described in any one of claims 1 to 6, which is characterized in that the oscillating plate it is described non- The recess portion of fixed part is configured to the parallel lines portion that extends parallel to second imaginary line and with from institute The both ends for stating parallel lines portion are separated from each other and towards curved a pair of of the convex curvature portions of the projecting inward mode of the recess portion,

The profile of the piezoelectric element have a pair of of straight line portion along a pair of respective parallel lines portion of recess portion, with And to curved in a manner of the pair of short side protrusion in the region folded by the pair of convex curvature portion in the pair of recess portion Bent bending section.

9. such as piezoelectricity sound part described in any one of claims 1 to 6, which is characterized in that the oscillating plate it is described non- The recess portion of fixed part by by towards second imaginary line protrusion in a manner of curved curved recessed portion constituted,

The profile of the piezoelectric element has along in a pair of curved recessed portion and the region folded by a pair of curved recess portion The curved bending section of mode protruded to the pair of short side.

10. piezoelectricity sound part as claimed in claim 2, which is characterized in that the on-fixed portion of the oscillating plate by with a thickness of 10 μm~150 μm of the alloy making sheet that nickel is combined in iron is constituted,

The piezoelectric element has structure made of the PZT multilayered ceramic multilayer with a thickness of 10 μm~35 μm,

It is 75~85 and with a thickness of 1 μ by the Shore D hardness of the piezoelectric element propylene class bonding agent Nian Jie with the oscillating plate M~10 μm.

11. a kind of piezoelectricity sound part has piezoelectricity pronunciation component and shell,

The piezoelectricity pronunciation component by metal oscillating plate and be set in at least one side of the oscillating plate piezoelectricity member Part is constituted,

The shell is configured to substantially fix the peripheral part of the oscillating plate of the piezoelectricity pronunciation component, and The first space and second space are formed in the two sides of the piezoelectricity pronunciation component, is formed in the wall portion opposite with first space It is formed with the resonator of 1 or more louver, wherein

Non-fixed portions positioned at the inside of the peripheral part of the oscillating plate have a pair of of long side and length relative to each other A pair of short edges shorter than the long side and relative to each other has a pair protruded to direction close to each other in the pair of long side Recess portion,

The piezoelectric element is set on the region between the pair of recess portion in the on-fixed portion of the oscillating plate,

The oscillating plate and the respective chamfered shape of the piezoelectric element are set to divide relative to by the pair of short side one The first imaginary line for two is symmetrical and symmetrical relative to the second imaginary line that the pair of long side is divided into two,

The ratio between the length L1 of the long side and the length W1 of the short side L1/W1 are set to fall into 1.25~1.75 range,

The on-fixed portion of the oscillating plate the recess portion the long side opening opening portion length L2 with it is described The ratio between the length L1 of long side L2/L1 is 0.4~0.7, towards between the pair of recess portion in the direction of second imaginary line The ratio between the length W1 of size W2 and short side W2/W1 is 0.4~0.95,

The total opening area and air chamber vol of described 1 or more louver of the resonator are set so as to work as conduct Input signal and 1 subresonance frequency, 3 subresonance frequencies and the 1 subresonance frequency when input sine wave signal with it is described The acoustic pressure of intermediate frequency between 3 subresonance frequencies is respectively in 80dB or more.

12. piezoelectricity sound part as claimed in claim 11, which is characterized in that be provided at the back side of the oscillating plate described Piezoelectric element.

13. piezoelectricity sound part as claimed in claim 12, which is characterized in that the resonator is constituted such that described 1 Between minimum acoustic pressure and the intermediate frequency and the 3 subresonance frequency between subresonance frequency and the intermediate frequency Minimum acoustic pressure is respectively in 80dB or more.

14. piezoelectricity sound part as claimed in claim 13, which is characterized in that

The L1/W1 is 1.40~1.45,

The L2/L1 is 0.45~0.55,

The W2/W1 is 0.55~0.59.

Technical field

The present invention relates to piezoelectricity sound part, the piezoelectricity pronunciation component of the piezoelectricity sound part is contained in equipped with playback In the shell in hole, the piezoelectricity sound part can obtain regulation or more in the frequency range of amount for being equivalent to multiple scales Acoustic pressure.

Background technique

In Fig. 7 of No. 3436205 bulletins (patent document 1) of Japanese Patent No., discloses and a kind of hold piezoelectric transducer The piezoelectricity sound part being contained in the shell with louver, the piezoelectric transducer are the piezoelectricity by chamfered shape for quadrangle Component affixing is in the piezoelectric transducer on the metal oscillating plate that chamfered shape is quadrangle.The piezoelectricity sound part can be The so-called piezoelectric speaker made a sound in wide frequency range.

Summary of the invention

Problems to be solved by the invention

In the piezoelectricity sound part shown in patent document 1, although the wide frequency range being able to use, acoustic pressure is low, deposits Such as the case where having the place of noise that cannot be heard like that as the car of outdoor or automobile.It is therefore desirable to be able to Reliably hear the piezoelectricity sound part of the sound of multiple scales.

The object of the present invention is to provide one kind can hear even if noise big place the sound of multiple scales Piezoelectricity sound part.

Means for solving the problems

The present invention using following piezoelectricity sound part as improved object, send out equipped with piezoelectricity by the piezoelectricity sound part Tone part and shell, the piezoelectricity pronunciation component is by metal oscillating plate and the pressure being set in at least one side of oscillating plate Electric device is constituted, and the shell is configured to substantially fix the peripheral part of the oscillating plate of piezoelectricity pronunciation component, press The two sides of electric pronunciation component form the first space and second space, are formed with 1 or more in the wall portion opposite with the first space Louver constitutes resonator by the louver of the volume in the first space and 1 or more.In piezoelectricity sound part of the invention, Non-fixed portions positioned at the inside of the peripheral part of oscillating plate have relative to each other a pair of of long side and length shorter than the long side and A pair of short edges relative to each other has a pair of of the recess portion protruded in a direction close to each other in a pair of of long side.Also, piezoelectricity member Part is set on the region between a pair of of recess portion in the on-fixed portion of oscillating plate, oscillating plate and the respective chamfered shape of piezoelectric element It is set to relative to the first imaginary line that a pair of short edges is divided into two symmetrical and relative to a pair of of long side is divided into two Second imaginary line is symmetrical.In addition, the length L1 of long side and the ratio between the length W1 L1/W1 of short side are set to fall into 1.25~1.75 Range.Also, resonator be constituted such that when as input signal and when input sine wave signal 1 subresonance frequency, 3 The acoustic pressure of intermediate frequency between subresonance frequency and 1 subresonance frequency and 3 subresonance frequencies is respectively in 80dB or more.

Particularly, resonator be preferably configured for make minimum acoustic pressure between 1 subresonance frequency and intermediate frequency and Minimum acoustic pressure between intermediate frequency and 3 subresonance frequencies is also in 80dB or more.

In addition, resonator also may be configured so that the intermediate frequency between 1 subresonance frequency and 3 subresonance frequencies Acoustic pressure is more than the acoustic pressure of 1 subresonance frequency and the acoustic pressure of 3 subresonance frequencies.

Since on-fixed portion is using the piezoelectricity sound part of the metal oscillating plate of so-called rectangular shape and using round Or the piezoelectricity sound part of the oscillating plates such as ellipse is compared, the non-serviceable space generated in the case where actual installation is (dead Area) it is few, therefore, in the product using piezoelectricity sound part, it is contemplated that have certain needs.But in the metal using rectangle In the case where the oscillating plate of system, it is difficult to obtain big acoustic pressure to a certain extent in defined frequency range.The inventors discovered that When using the oscillating plate in a pair of of long side with recess portion, the frequency of the acoustic pressure and 3 subresonance frequencies that obtain 1 subresonance frequency is not It can become too big, and the acoustic pressure in each resonant frequency is without the frequency characteristic of very big difference.In addition, the inventors discovered that, When being set in the resonator shell equipped with defined louver, can increase between 1 subresonance frequency and 3 subresonance frequencies Intermediate frequency region in acoustic pressure.Based on these understanding, according to the present invention it is possible to obtain can be in the journey across multiple scales The piezoelectricity sound part of the acoustic pressure of 80dB or more is obtained in the frequency range of degree.To according to the present invention, so-called using using The piezoelectricity pronunciation component of the metal oscillating plate of rectangular shape can be heard even if noise big place.

Shell can have the opening portion to form shape identical with the chamfered shape in on-fixed portion of oscillating plate, and have There is the pronunciation component holder that the peripheral part of oscillating plate is fixed.When using such pronunciation component holder, vibration The chamfered shape in the on-fixed portion of plate is determined by the shape of opening portion.To which square can be used as the shape of oscillating plate Shape can reduce the processing price of oscillating plate.

A pair of short edges can also have at both ends to the inclined a pair of angled portion in direction close to each other.When setting in this way When a pair of angled portion, by changing the tilt angle of rake, the acoustic pressure of frequency characteristic can be improved.

The shape of the recess portion in the on-fixed portion of oscillating plate can use various shape.The shape quilt of representative recess portion It is configured to parallel lines portion and a pair of angled straight line portion, the parallel lines portion is parallel to the extension of the first imaginary line, described A pair of angled straight line portion is separated from each other from the both ends in the parallel lines portion and extends towards the remainder of long side.In the feelings Under condition, it is preferable that the profile of piezoelectric element use with along the respective parallel lines portion of a pair of of recess portion a pair of of straight line portion, with And the profile of bending section, the bending section is with straight in a pair of angled opposite with the direction of the second imaginary line of a pair of of recess portion extension It is bent in region folded by line portion to the mode that a pair of short edges is protruded.It can be bent by suitably changing the bending of piezoelectric element Rate adjusts the difference on the frequency between 1 subresonance frequency and 3 subresonance frequencies.

In addition, the recess portion in the on-fixed portion of oscillating plate can also be configured to extending with being parallel to the second imaginary line Parallel lines portion and a pair of of convex curvature portion, the pair of convex curvature portion is with from the both ends phase in the parallel lines portion It mutually separates and is bent towards the projecting inward mode of recess portion.Preferably, in this case, the profile of piezoelectric element has along a pair A pair of of straight line portion and bending section in the respective parallel lines portion of recess portion, the bending section is in the pair of of a pair of of recess portion It is bent in region folded by convex curvature portion to the mode that a pair of short edges is protruded.It in this case, can also be by suitably changing The bending curvature of the bending section of transformation electric device adjusts the difference on the frequency between 1 subresonance frequency and 3 subresonance frequencies.

In turn, the recess portion in the on-fixed portion of oscillating plate is by the curved curved recessed portion in a manner of towards the second imaginary line protrusion It constitutes, the profile of piezoelectric element also can have along a pair of curved recessed portion and the region folded by a pair of curved recess portion The interior curved bending section of mode protruded to a pair of short edges.

In addition, as the actual use item in the case where the alarm to car or to outside vehicle as automobile carrys out use Part is preferably as described below.Preferably, the on-fixed portion of oscillating plate in iron by being combined with nickel with a thickness of 10 μm~150 μm Alloy making sheet is constituted, and piezoelectric element has by structure made of the PZT multilayered ceramic multilayer with a thickness of 10 μm~35 μm, by piezoelectricity The Shore D hardness of the element propylene class bonding agent Nian Jie with oscillating plate is 75~85 and with a thickness of 1 μm~10 μm.

In turn, from about 2kHz in the case where obtaining a degree of acoustic pressure between about 3kHz, piezoelectricity sound portion Part has piezoelectricity pronunciation component and shell, and the piezoelectricity pronunciation component is by metal oscillating plate and is set to oscillating plate extremely Piezoelectric element in few one side is constituted, and the shell was configured to the peripheral part of the oscillating plate of piezoelectricity pronunciation component throughout complete cycle Ground is fixed, and forms the first space and second space in the two sides of piezoelectricity pronunciation component, also, opposite with the first space Wall portion is formed with 1 or more louver, and following structure is used in the piezoelectricity sound part.That is, being located at oscillating plate The non-fixed portions of the inside of peripheral part have shorter than the long side and relative to each other one of a pair of of long side and length relative to each other To short side, there is a pair of of the recess portion protruded to direction close to each other in a pair of of long side.Piezoelectric element is set to oscillating plate On region between a pair of of recess portion in on-fixed portion.Also, oscillating plate and the respective chamfered shape of piezoelectric element are set to It is symmetrical relative to the first imaginary line that a pair of short edges is divided into two and imaginary relative to second that a pair of of long side is divided into two Line is symmetrical.On this basis, the ratio between length W1 of length L1 and short side of long side L1/W1 is set to fall into 1.25~1.55 Range, in the length L2 of the opening portion of the long side opening of the recess portion in the on-fixed portion of oscillating plate and the ratio between the length L1 L2/ of long side L1 is 0.4~0.6, the ratio between length W1 of size W2 and short side between a pair of of recess portion in the direction of the second imaginary line of direction W2/ W1 is 0.4~0.95.In this case, the total opening area of 1 or more louver of the resonator equipped with 1 or more louver And air chamber vol be set so that when as input signal and when input sine wave signal 1 subresonance frequency, 3 times altogether The acoustic pressure of intermediate frequency between vibration frequency and 1 subresonance frequency and 3 subresonance frequencies is respectively in 80dB or more.Also, In In this case, it is preferable that the acoustic pressure of intermediate frequency is set to the sound of acoustic pressure and 3 subresonance frequencies in 1 subresonance frequency It is more than pressure.Particularly, resonator be preferably configured for make minimum acoustic pressure between 1 subresonance frequency and intermediate frequency and in Between minimum acoustic pressure between frequency and 3 subresonance frequencies respectively in 80dB or more.Preferably, in this case, 1.40 L1/W1 ~1.45, L2/L1 are that 0.45~0.55, W2/W1 is 0.55~0.59.

Detailed description of the invention

Fig. 1 (A) is the exploded perspective view of the piezoelectricity sound part equipped with piezoelectricity pronunciation component of present embodiment, Fig. 1 It (B) is the line B-B exploded perspective view of Fig. 1 (A).

Fig. 2 is the top view of piezoelectricity pronunciation component.

Fig. 3 (A) is to indicate the existing piezoelectricity sound part referred to as piezoelectric buzzer using disk-shaped oscillating plate Frequency characteristic an example figure, Fig. 3 (B) be as indicating to illustrate in patent document 1 be referred to as piezoelectricity loudspeaking The figure of one example of the frequency characteristic of the piezoelectricity sound part of the oscillating plate rectangular shaped of device, Fig. 3 (C) is to indicate this implementation The figure of one example of the frequency characteristic of the piezoelectricity sound part of mode.

Fig. 4 is to indicate to work as to use oblateness (circle, ellipse etc.) (A), quadrangle (B), hexagon as oscillating plate (C), octagon (D) and dumb-bell shape (E) and the piezoelectricity member substantially the same configured with area in the central portion of these oscillating plates When part, the region of the node of the shape and vibration of the oscillating plate in the case where changing aspect ratio and to 1 vibration frequency and The figure for the result that the frequency of 3 vibration frequencies is measured.

Fig. 5 (A) to (E) is 1 vibration frequency, 3 subresonance frequencies and the intermediate frequency in the case where indicating change aspect ratio The figure of the measurement result of rate.

Fig. 6 is oblateness (circle, ellipse etc.) (A), quadrangle indicated when using same aspect ratio as oscillating plate (B), when hexagon (C), octagon (D) and dumb-bell shape (E), the figure of the frequency characteristic only obtained by piezoelectricity pronunciation component.

Fig. 7 (A) to (D) is indicated in the variform situation of recess portion, same aspect ratio (1:1.3) the case where Under, how to change the figure of the result confirmed to the poor Δ of 1 subresonance frequency and 3 subresonance frequencies.

Fig. 8 (A) and (B) are the frequencies for indicating the piezoelectricity sound part in the case where changing the geomery of piezoelectric element The figure of the variation of characteristic.

Fig. 9 is pressed the case where increasing identical aspect ratio compared with indicating with Fig. 8 the case where under (1:1.4) when changing The figure of frequency characteristic when the width dimensions W and length dimension L of electric device.

Figure 10 is to indicate in the case where changing the total opening area of louver of resonator, how to be changed to frequency characteristic The figure of one example of the result tested.

Figure 11 is to indicate that the quantity of louver is less become 5 from 1 for the total opening area variation of louver In the case where the figure of result tested of influence.

Figure 12 (A) is the half portion cutting perspective view of the piezoelectricity sound part of second embodiment, and Figure 12 (B) is its decomposition Perspective view.

Figure 13 (A) is the top view of the piezoelectricity pronunciation component used in the second embodiment, and Figure 13 (B) is piezoelectricity hair The rearview of tone part.

Figure 14 (A) is the acoustic pressure-frequency characteristic for indicating to be measured without using acoustic resonator by piezoelectricity pronunciation component monomer Figure, Figure 14 (B) is the acoustic pressure-frequency characteristic figure indicated using the piezoelectricity sound part of acoustic resonator.

Figure 15 (A) and (B) be the top view of the variation of the piezoelectricity pronunciation component used in the second embodiment with And rearview.

Figure 16 (A) to (D) is the figure for indicating the vibrational state of the piezoelectric vibration device vibrated with different vibration modes.

Figure 17 (A) is the acoustic pressure-frequency characteristic for indicating to be measured without using acoustic resonator by piezoelectricity pronunciation component monomer Figure, Figure 17 (B) is the acoustic pressure-frequency characteristic figure indicated using the piezoelectricity sound part of acoustic resonator.

Figure 18 (A) and (B) are bowing for the piezoelectricity pronunciation component used in the piezoelectricity acoustic pressure component of third embodiment View and rearview.

Figure 19 is indicated in third embodiment, L1:L2 1:0.2,1:0.3 and 1:0.4, L1:W1 1:1, 1.25:1,1.5:1,1.75:1 and 2:1,1 intrinsic vibration frequency in the case that W2/W1 is changed in the range of 0.2~1 Rate ◆ and the figure of the variation of 3 eigentone ■.

Figure 20 is indicated in third embodiment, L1:L2 1:0.5,1:0.6 and 1:0.7, L1:W1 1:1, 1.25:1,1.5:1,1.75:1 and 2:1,1 intrinsic vibration frequency in the case that W2/W1 is changed in the range of 0.2~1 Rate ◆ and the figure of the variation of 3 eigentone ■.

Figure 21 (A) to (I) is indicated in third embodiment, only in the case where changing L1:L2 and L1:W1 Acoustic pressure-frequency characteristic the figure obtained by piezoelectricity pronunciation component.

Figure 22 (A) to (E) is indicated in the 4th embodiment, when the thickness of louver is constant, changes playback When bore dia and air chamber vol, how to change the figure for the result tested to acoustic pressure-frequency characteristic.

Specific embodiment

In the following, being illustrated referring to embodiment of the attached drawing to piezoelectricity sound part of the invention.

[first embodiment]

Fig. 1 (A) indicates the exploded perspective view of the piezoelectricity sound part 1 equipped with piezoelectricity pronunciation component of present embodiment, Fig. 1 (B) is the line B-B exploded perspective view of Fig. 1 (A).Fig. 2 is the top view of piezoelectricity pronunciation component.In addition, in present embodiment In, for ease of understanding, the description that the thickness of a part of component is exaggerated.It is pressed shown in Fig. 1 (A) and (B) Electric sound part 1 is the use in order to generate alarm in the environment more than noise such in such as automobile with the sound of multiple scales The piezoelectricity sound part used on the way.

Piezoelectricity sound part 1 has shell 6, and the shell 6 is matched between downside case half 3 and upside case half 5 Pronunciation component holder 9 is had, the pronunciation component holder 9 has opening portion 7.Downside case half 3 is exhausted by polypropylene etc. Edge resin integrally shapes, with rectangular bottom wall part 31 and the peripheral wall portion 32 holded up from the peripheral part of bottom wall part 31.Under The peripheral wall portion 32 that side body half portion 3 has rectangular bottom wall part 31 and holds up from the peripheral part of bottom wall part 31.Upper side body half Portion 5 is integrally shaped by insulating resins such as polypropylene, is had rectangular upper wall portions 51 and is erected from the peripheral part of upper wall portions 51 The peripheral wall portion 32 risen.Upside case half 5 has rectangular upper wall portions 51 and erects downwards from the peripheral part of upper wall portions 51 Peripheral wall portion 52.In upper wall portions 51,4 louvers 4 have been formed about in quadrangle.

Pronunciation component retainer 9 by low thermal expansion hard insulating resin, for example in polybutylene terephthalate (PBT) Insulating resin made of middle addition glass etc. integrally shapes, and the oscillating plate 12 of piezoelectricity pronunciation component 11 is fixed using bonding Around opening portion 7.Opening portion 7 is in the on-fixed portion with the oscillating plate 12 for the piezoelectricity pronunciation component that will be described in detail below The identical shape of 13 chamfered shape.Specifically, the on-fixed portion 13 of oscillating plate 12 have relative to each other a pair of of long side 7A and The length relative to each other a pair of short edges 7B shorter than long side 7A has in a pair of of long side 7A and protrudes in a direction close to each other A pair of of protrusion 7C.The chamfered shape of opening portion 7, the i.e. chamfered shape in on-fixed portion 13 of oscillating plate 12 have relative to by one The first imaginary line PL1 being divided into two to short side 7B is symmetrical and relative to the second imaginary line that a pair of of long side 7A is divided into two The symmetrical shape of PL2.

In addition, downside case half 3, pronunciation component retainer 9 and upside case half 5 are in peripheral wall portion 32 and peripheral wall portion The state that pronunciation component retainer 9 is clipped between 52 is mutually hermetic engaged by ultrasonic bonding, completes shell 6.As a result, In the state that piezoelectricity pronunciation component 11 is fixed in pronunciation component retainer 9, in the inside of shell 6, in piezoelectricity pronunciation component Two sides form the first space S 1 and second space S2.Louver 4 is connected to the first space S 1.First space S 1 constitutes resonator Air chamber.

As shown in Fig. 2, piezoelectricity pronunciation component 11 is by metal oscillating plate 12 and is arranged at least the one of oscillating plate 12 Piezoelectric element 15 on face is constituted.The on-fixed portion of oscillating plate 12 has a pair of of long side 13A and length relative to each other longer than this Side 13A short a pair of short edges 13B relative to each other has a pair protruded in a direction close to each other in a pair of of long side 13A Recess portion 13C.Piezoelectric element 15 is set on the region between a pair of of recess portion 13C of oscillating plate 12, the on-fixed portion of oscillating plate 12 13 and the respective chamfered shape of piezoelectric element 15 be set to relative to the first imaginary line that a pair of short edges 13B is divided into two PL1 is symmetrical and symmetrical relative to the second imaginary line PL2 that a pair of of long side 13A is divided into two.The shape of recess portion 13C can use Various shape.The recess portion 13C of present embodiment is configured to the parallel lines portion extended parallel to the first imaginary line PL1 13Ca and be separated from each other from the both ends of parallel lines portion 13Ca and towards the remainder of corresponding long side 13A extend A pair of angled straight line portion 13Cb.In this case, the profile of piezoelectric element 15 has respective parallel along a pair of of recess portion 13C A pair of of straight line portion 15A of straight line portion 13Ca and by opposite with the direction of the second imaginary line PL2 of a pair of of recess portion 13C extension The region that clips a pair of angled straight line portion 13Cb in the curved bending section 15B in a manner of towards a pair of short edges 13B protrusion.It is logical Cross the curved curvature for suitably changing the bending section 15B of piezoelectric element 15, adjustable 1 subresonance frequency and 3 subresonances frequency Difference on the frequency between rate.

In the present embodiment, the shape in the on-fixed portion 13 of oscillating plate 12 is set so that the non-of the oscillating plate 12 The ratio between the length W1 of length L1 and short side 13B of the long side 13A of fixed part 13 L1/W1 falls into 1.25~1.75 range, is equipped with 1 The resonator of a above louver is set so that when 1 subresonance frequency as input signal and when input sine wave signal The acoustic pressure of intermediate frequency between 3 subresonance frequencies 1 subresonance frequency acoustic pressure and 3 subresonance frequencies acoustic pressure with On.In addition, as will be explained, the quantity of louver is arbitrary.

[frequency characteristic of embodiment]

Fig. 3 (A) indicates the pressure referred to as piezoelectric buzzer in the existing on-fixed portion using disk-shaped oscillating plate In electric sound part, when as input signal and an example of frequency characteristic when input sine wave signal.Such as from figure As out, in piezoelectric buzzer, if acoustic pressure is got higher under a resonant frequency (in this embodiment, for 90dB with On).In contrast, Fig. 3 (B) indicates that the oscillating plate referred to as piezoelectric speaker as illustrating in patent document 1 is in square One example of the frequency characteristic of the piezoelectricity sound part of shape.Fig. 3 (C) indicates the frequency of the piezoelectricity sound part of present embodiment One example of characteristic.

As shown in Fig. 3 (B), even with the piezoelectric speaker in the on-fixed portion of the oscillating plate of rectangular shape, also require In very wide frequency range, acoustic pressure is almost flat (in this example embodiment, being the acoustic pressure of 70dB).As present embodiment that Sample, the piezoelectric speaker one using the piezoelectricity sound part 1 of the metal oscillating plate 12 of so-called rectangular shape, with Fig. 3 (B) Sample, it is difficult to which big acoustic pressure to a certain extent is obtained in defined frequency range, and (in Fig. 3 (C), frequency characteristic A is only The case where for piezoelectricity pronunciation component).

The inventors discovered that as in the present embodiment, when using a pair of of long side in the on-fixed portion 13 of oscillating plate 12 When oscillating plate 12 in 13A with recess portion 13C, obtain when the 1 subresonance frequency as input signal and when input sine wave signal The frequency of the acoustic pressure of rate and 3 subresonance frequencies will not become too big, and the acoustic pressure under respective resonant frequency is in 80dB or more Frequency characteristic.In addition, the inventors discovered that, when defined louver 4 is arranged on shell 6, can increase when as defeated The acoustic pressure in the intermediate frequency region between 1 subresonance frequency and 3 subresonance frequencies when entering signal and input sine wave signal (referring to the frequency characteristic B of Fig. 3 (C)).It according to the present embodiment, can be across the frequency range of the degree of multiple scales (being substantially 1.7kHz~substantially 3.6kHz in the example of Fig. 3 (C)) obtains the acoustic pressure of 80dB or more.To according to this implementation Mode can be provided using the piezoelectricity pronunciation component for the metal oscillating plate for using so-called rectangular shape even if in noise Big place can also hear the piezoelectricity sound part of the sound of defined frequency range.

[determination of the shape in the on-fixed portion of oscillating plate]

The reasons why illustrating the shape in the on-fixed portion 13 for determining oscillating plate 12 in the above-described embodiment below.Fig. 4 is indicated When the on-fixed portion as oscillating plate uses oblateness (circle, ellipse etc.) (A), quadrangle (B), hexagon (C), octagon (D) and dumbbell shape (E) (shape in a pair of of long side as in the present embodiment with a pair of of recess portion), and in these vibrations When the central portion in the on-fixed portion of movable plate configures substantially the same piezoelectric element of area, changing aspect ratio (long axis or long side With the ratio between short axle or short side) in the case where oscillating plate on-fixed portion shape and vibration node region and to 1 time The result that the frequency of resonant frequency and 3 subresonance frequencies is measured.The column of the right end of Fig. 4 indicate aspect ratio as a reference example The shape of piezoelectric element when for 1:1.5.Also, Fig. 5 (A) to (E) is indicated in the case where changing aspect ratio, when as input The measurement knot of signal and 1 subresonance frequency (◆), 3 subresonance frequencies (■) and intermediate frequency (▲) when exporting sine wave signal Fruit.In addition, intermediate frequency is that louver is arranged on shell in the same manner as above embodiment to can be improved the frequency of acoustic pressure.Such as Compare as Fig. 5 (A) finds out to (E), when the on-fixed portion of the oscillating plate using the dumbbell shape used in the present embodiment When, 1 subresonance frequency and 3 subresonance frequencies can be increased, also, narrow the difference of 1 subresonance frequency and 3 subresonance frequencies.Separately Outside, Fig. 6 is indicated when the oblateness (circle, ellipse etc.) (A) as oscillating plate using same aspect ratio, quadrangle (B), six sides When shape (C), octagon (D) and dumbbell shape (E), only piezoelectricity pronunciation component obtain frequency characteristic.Such as can be seen from Figure 6 that The difference of 1 subresonance frequency and 3 subresonance frequencies can be reduced to minimum in dumbbell shape (E) by sample.Present embodiment as a result, The dumbbell shape (E) of middle use as the on-fixed portion of preferred oscillating plate chamfered shape and be determined.

[variation of the recess portion in the on-fixed portion 13 of oscillating plate 12]

Fig. 7 (A) to (D) is indicated in the variform situation of the recess portion in the on-fixed portion 13 of oscillating plate 12, identical Aspect ratio (1:1.3) in the case where, how the knot confirmed is changed to the difference Δ of 1 subresonance frequency and 3 subresonance frequencies Fruit.The recess portion 13C of Fig. 7 (A) is recess portion identical with above embodiment.

Fig. 7 (B) indicates the recess portion 13C in the on-fixed portion 13 of oscillating plate 12 by curved in a manner of towards the second imaginary line protrusion Bent curved recessed portion is constituted, and the profile of piezoelectric element not shown in the figure has along a pair of curved recess portion and by a pair of curved In the region that bent recess portion clips the case where bending section curved to the mode of a pair of short edges protrusion.

The recess portion 13C in the on-fixed portion 13 of the oscillating plate 12 of Fig. 7 (C) is configured to have to be prolonged in parallel with the second imaginary line The parallel lines portion 13Ca that stretches and with separated from each other from the both ends of parallel lines portion 13Ca and to recess portion 13C convex Curved a pair of of the convex curvature portion 13b ' of mode out.In this case, the profile of piezoelectric element not shown in the figure also has Along a pair of of straight line portion of the respective parallel lines portion 13Ca of a pair of of recess portion 13C and in a pair of of convex by a pair of of recess portion The curved bending section of mode protruded in the region that bending section 13b ' is clipped to a pair of short edges.In this case, can also pass through Change the curved curvature of piezoelectric element suitably to adjust the difference on the frequency between 1 subresonance frequency and 3 subresonance frequencies.

[shape of piezoelectric element]

Fig. 8 (A) and (B) are indicated in the case where changing the geomery of piezoelectric element 15, when defeated as input signal The variation of the frequency characteristic of piezoelectricity sound part when entering sine wave signal.Fig. 8 (A) indicates that when the aspect ratio of oscillating plate 12 be 1: 1.3, the constant width dimensions (along the size in the direction of the second imaginary line PL2) of piezoelectric element (PZT ceramics) are 13mm, and are changed Become along the direction of the first imaginary line PL1 length dimension (the protrusion size of the bending section 15B of Fig. 2) when frequency characteristic change Change, Fig. 8 (B) is indicated in the case where the shape of piezoelectric element is rectangular shape, when the aspect ratio of oscillating plate 12 is 1:1.3, pressure The constant width dimensions (along the size in the direction of the second imaginary line PL2) of electric device (PZT ceramics) are 13mm, and change along The variation of frequency characteristic when the length dimension in the direction of the first imaginary line PL1.From Fig. 8 (A) and (B) as can be seen that along the The length dimension and shape in the direction of one imaginary line PL1 have an impact to the acoustic pressure of the first resonant frequency and the second resonant frequency.In The lower area of Fig. 8 (A) and (B) indicate the top view of piezoelectricity pronunciation component (a) to (j), there is shown as each object The shape of piezoelectric element.From Fig. 8 (A) and (B) although as can be seen that when will be along the length ruler in the direction of the first imaginary line PL1 It is very little that the acoustic pressure of 1 subresonance frequency and 3 subresonance frequencies rises when being formed long, but when too long, the sound of 1 subresonance frequency The difference of the acoustic pressure of pressure and 3 subresonance frequencies becomes extreme big.For this tendency, in piezoelectric element along the first imaginary line Under the case where being totally rectangular in shape shape of the direction of PL1 (Fig. 8 (B)), this tendency is stronger.If it is considered that such incline Always determine that the shape of piezoelectric element is then ideal.

Fig. 9 is indicated the case where increasing identical aspect ratio compared with Fig. 8 under (1:1.4), when the width for changing piezoelectric element Size W2 (along the size in the direction of the second imaginary line PL2) and length dimension L are spent (along the direction of the first imaginary line PL1 Size) when, the frequency characteristic as input signal when input sine wave signal.That found out such as is compared to Fig. 8 and Fig. 9 Sample, when increasing aspect ratio, although the difference of the acoustic pressure of the acoustic pressure of 1 subresonance frequency and 3 subresonance frequencies becomes larger, when lengthening When the length dimension of piezoelectric element, the difference of the acoustic pressure of the acoustic pressure of 1 subresonance frequency and 3 subresonance frequencies will not become larger, Er Qie Acoustic pressure will not generate big fluctuation in the high range of frequency.In fact, suitably being adjusted in view of the tendency found out from Fig. 8 and Fig. 9 The shape and size of seamless electric device.

[effect of resonator (louver of shell)]

Figure 10 is indicated in the present embodiment, in the total opening area of the louver for resonator, as an example In the case where volume by the volume (the air chamber vol of resonator) of ante-chamber from 1.8cc change to 10cc, believe as input Number and how frequency characteristic when input sine wave signal changes the result tested.In addition, in this experiment, oscillating plate Aspect ratio is 1:1.3, and the shape of piezoelectric element is oblateness, width dimensions is fixed as 10mm, length dimension is fixed as 15mm. In order to change the total opening area of louver in this state, 1 louver is set, and by its diameter 2..5mm~ It is correspondingly changed in the range of 9.9mm with the volume of ante-chamber.In addition, fcav is the value of intermediate frequency in Figure 10.From In Figure 10 as can be seen that when total opening area is too big (the case where e), if the total opening area of louver is in suitable model It encloses, then the value of intermediate frequency there will not be big to variation, moreover, the acoustic pressure of intermediate frequency will not generate very big difference.In addition, Figure 11 indicates to change less the total opening area of louver, and the number of louver is changed from 1 in the case where 5 The result tested of influence.Due to when the volume of ante-chamber is 7.5cc, the acoustic pressure of 1 subresonance frequency and 3 subresonance frequencies The difference of acoustic pressure do not become larger, and obtain the frequency characteristic of high sound pressure, therefore, the volume of ante-chamber be selected as 7.5cc.Playback The case where experimental condition other than the number in hole is with the test of Figure 10 is identical.It can be seen from figure 11 that if total opening area not Become, then the number of louver does not influence frequency characteristic.To, if it can be seen from the result louver number At 1 or more.In addition, the conclusion is derived conclusion in the present embodiment, in the institute that the structure of resonator changes Under there is something special, do not determine whether to be common result.

[condition of embodiment]

The piezoelectricity pronunciation component and resonator (shell and louver) used in above-mentioned each test meets item below Part.The on-fixed portion 13 of oscillating plate 12 is preferably by the plate structure of the alloy for being combined with nickel in iron with a thickness of 10 μm~150 μm At.In addition, piezoelectric element preferably has structure made of the PZT multilayered ceramic multilayer with a thickness of 10 μm~35 μm.In turn, excellent Selection of land, the Shore hardness that piezoelectric element is adhered to the bonding agent of the propylene class of oscillating plate is 75~85 and with a thickness of 1 μm~10 μ m。

[second embodiment]

Figure 12 (A) and (B) are the half portion cutting perspective views of the piezoelectricity sound part 1 of second embodiment and its decompose vertical Body figure, Figure 13 (A) are the top views of the piezoelectricity pronunciation component 11 used in the second embodiment, and Figure 13 (B) is piezoelectricity hair The back view of tone part.Second embodiment is compared with Fig. 1 and first embodiment shown in Fig. 2, piezoelectricity pronunciation component 11 shape and the position of louver 4 and number difference.In others point from first embodiment without different.Therefore, In In Figure 12 and Figure 13, for part identical with Fig. 1 and first embodiment shown in Fig. 2, assign with for explanatory diagram 1 and The identical appended drawing reference of the appended drawing reference of Fig. 2, and the description thereof will be omitted.In the present embodiment, the vibration of piezoelectricity pronunciation component 11 12 rectangular shaped of plate, piezoelectric element 15 are pasted on the back side of oscillating plate 12.In the present embodiment, the on-fixed of oscillating plate 12 The chamfered shape in portion 13 forms so-called dumb-bell shape.

Using such structure, it is not necessary that implement particularly to process to oscillating plate 12.In addition, in the present embodiment, In upside, the center of the upper wall portions 51 of case half 5 is formed with 1 louver 4.Figure 14 (A) expression does not use acoustic resonator (downside Case half 3) and by acoustic pressure-frequency characteristic of 11 monomer of piezoelectricity pronunciation component measurement, Figure 14 (B) is indicated using acoustic resonator Acoustic pressure-frequency characteristic of piezoelectricity sound part.As being compared as finding out to Figure 14 (A) and (B), 1.7kHz~ In the range of 3kHz, acoustic pressure rises.

[variation of the shape in the on-fixed portion of oscillating plate]

Figure 15 (A) and (B) indicate the variation of the piezoelectricity pronunciation component 11 used in the second embodiment.The piezoelectricity The chamfered shape in the on-fixed portion 13 of the dumb-bell shape of the oscillating plate 12 of pronunciation component 11 is that a pair of short edges 13B has respective Both ends are to the inclined a pair of angled portion 13Ba in direction close to each other.When such a pair of angled portion 13Ba is arranged, pass through The tilt angle for changing rake 13Ba can carry out the improvement for improving the high frequency component of frequency characteristic.That is, when using the pressure When the shape of electric pronunciation component 11, it can be made such as the increased improvement of the acoustic pressure of frequency-portions indicated by an arrow in Figure 17 A. Figure 16 (A) to (D) is to indicate to shake in the case where vibrating the piezoelectricity pronunciation component with 1 vibration mode, with 3 vibration modes The vibration of oscillating plate 12 in the case where dynamic, in the case where being vibrated with 4 vibration modes, in the case where being vibrated with 5 vibration modes The figure of dynamic state.In these figures, white part is the part of deformation and protrusion, and black part is to deform and recessed part. Figure 17 (A) expression does not use acoustic resonator (downside case half 3) and by acoustic pressure-frequency of 11 monomer of piezoelectricity pronunciation component measurement Characteristic, Figure 17 (B) indicate acoustic pressure-frequency characteristic of the piezoelectricity sound part using acoustic resonator.Such as Figure 14 (A) and (B) are carried out Compare as finding out, in the range of 1.7kHz~3kHz, compared with improving before, acoustic pressure rises.

[third embodiment]

Figure 18 (A) and (B) are the piezoelectricity pronunciation components 11 used in the piezoelectricity sound part of third embodiment Top view and rearview.Compared with third embodiment second embodiment shown in Figure 12 and Figure 13, piezoelectricity pronunciation member The shape of part 11 is different.Others point is from second embodiment without different.Therefore, in Figure 18, for Figure 12 and figure The identical part of second embodiment shown in 13 assigns the identical attached drawing of appended drawing reference for being used for explanatory diagram 12 and Figure 13 Label, and the description thereof will be omitted.In the present embodiment, 12 rectangular shaped of oscillating plate of piezoelectricity pronunciation component 11, piezoelectric element 15 are pasted on the back side of oscillating plate 12.In the present embodiment, the chamfered shape in the on-fixed portion 13 of oscillating plate 12 is formed as not With the angled straight lines portion possessed by the on-fixed portion 13 of the oscillating plate in first embodiment and second embodiment So-called dumb-bell shape.That is, recess portion 13C is in complete rectangular shape.Using the structure, do not need to implement oscillating plate 12 particularly Processing.In addition, in the present embodiment, in the same manner as second embodiment, the center of the upper wall portions of case half in upside It is formed with 1 louver.

Figure 19 is to indicate in the present embodiment, the L1:L2 shown in Figure 18 (A) be 1:0.2,1:0.3 and 1:0.4, L1:W1 is 1.25:1,1.5:1,1.75:1 and 2:1, in the case that W2/W1 changes in the range of 0.2~1, when as defeated Enter signal and 1 eigentone when input sine wave signal ◆ and the figure of the variation of 3 eigentone ■.Separately Outside, Figure 20 is to indicate in the present embodiment, and the L1:L2 shown in Figure 18 (A) is 1:0.5,1:0.6 and 1:0.7, L1:W1 1 intrinsic vibration frequency in the case where changing in the range of 0.2~1 for 1.25:1,1.5:1,1.75:1 and 2:1, W2/W1 Rate ◆ and the figure of the variation of 3 eigentone ■.

In addition, Figure 21 (A) to (C) is to indicate that in L1:L2 be 1:0.4, the case where L1:W1 1.4:1,1.5:1,1.6:1 Under only by piezoelectricity pronunciation component obtain when acoustic pressure-frequency characteristic figure as input signal and when input sine wave signal. In addition, Figure 21 (D) to (F) be indicate L1:L2 be in the case that 1:0.5 L1:W1 is 1:1,1.4:1,1.5:1,1.6:1 only By piezoelectricity pronunciation component obtain when acoustic pressure-frequency characteristic figure as input signal and when input sine wave signal.Into And Figure 21 (G) to (I) be indicate L1:L2 be in the case that 1:0.6 L1:W1 is 1:1,1.4:1,1.5:1,1.6:1 only by The expression that piezoelectricity pronunciation component obtains is when acoustic pressure-frequency characteristic figure as input signal and when input sine wave signal.Such as As finding out when observing Figure 19 to Figure 21, it is set to fall into when by the ratio between the length W1 of the length L1 of long side and short side L1/W1 1.25~1.75 range, length L2 and long side in the opening portion of the long side upper opening of the recess portion in the on-fixed portion of oscillating plate The ratio between length L1 L2/L1 is 0.4~0.7, the size W2's and short side between a pair of of recess portion in the direction of the second imaginary line of direction When the ratio between length W1 W2/W1 is 0.4~0.95, in the range of about 2kHz~about 3kHz, acoustic pressure rises.It is sent out by these piezoelectricity In the case that tone part is packed into the shell for constituting 1 or more resonator, the total opening area and air chamber of 1 or more louver Capacity is set so that when the 1 subresonance frequency, 3 subresonance frequencies, 1 time as input signal and when input sine wave signal The acoustic pressure of intermediate frequency between resonant frequency and 3 subresonance frequencies is respectively in 80dB or more.In turn, 1 or more louver Total opening area and air chamber vol be preferably set to so that when 1 time as input signal and when input sine wave signal altogether The acoustic pressure of intermediate frequency between vibration frequency and 3 subresonance frequencies is in the acoustic pressure of 1 subresonance frequency and the acoustic pressure of 3 subresonance frequencies More than.

[the 4th embodiment]

In the same manner as third embodiment shown in 4th embodiment and Figure 18 (A) and (B), piezoelectricity pronunciation component Oscillating plate rectangular shaped, piezoelectric element are glued to the back side of oscillating plate, and the chamfered shape in the on-fixed portion of oscillating plate is formed For without the angled straight lines possessed by the on-fixed portion of the oscillating plate in first embodiment and second embodiment The so-called dumb-bell shape in portion.That is, recess portion (13C) is in complete rectangular shape.The length L1 of the long side of used oscillating plate (12) The ratio between the length W1 (21mm) of (30mm) and short side L1/W1 is 1.43, is opened in the long side of the recess portion in the on-fixed portion of oscillating plate The ratio between the length L2 (15mm) of the opening portion of mouth and the length L1 of long side L2/L1 are 0.5, towards the one of the direction of the second imaginary line The ratio between length W1 W2/W1 to size W2 (12mm) and short side between recess portion is 0.57.In addition, in the present embodiment, with Similarly, in upside, the center of the upper wall portions of case half is formed with 1 louver (4) to second embodiment.In addition, vibration The on-fixed portion (13) of plate (12) is made of the plate of the alloy for being combined with nickel in iron with a thickness of 50 μm.In addition, piezoelectricity is first Part has structure made of the PZT multilayered ceramic multilayer with a thickness of 20 μm.In turn, piezoelectric element is adhered to the third of oscillating plate Alkenes bonding agent Shore D hardness be 82 and its with a thickness of about 1~10 μm.

Also, Figure 22 (A) to (E) indicates that when the thickness of louver (4) be 1mm, the radius and air of louver (4) Chamber vol is 5.5mm and 6cc, 7mm and 8cc, 8.5mm and 10cc, 10mm and when 10cc and 11.5mm and 14cc, to as How acoustic pressure-frequency characteristic for input signal when input sine wave signal changes the result tested.Such as from Figure 22 As (A) is found out to (E), under any conditions, when the 1 subresonance frequency as input signal and when input sine wave signal The acoustic pressure of intermediate frequency between rate, 3 subresonance frequencies and 1 subresonance frequency and 3 subresonance frequencies is respectively in 80dB or more. In addition, the acoustic pressure of the intermediate frequency between 1 subresonance frequency and 3 subresonance frequencies is at 1 time in the example of Figure 22 (A) and (B) It is more than the acoustic pressure of the acoustic pressure of resonant frequency and 3 subresonance frequencies.In the example of Figure 22 (C) to (E), resonator is configured to make Obtain the minimum acoustic pressure and intermediate frequency in the frequency range of 1.8KHz~3.2KHz, between 1 subresonance frequency and intermediate frequency Minimum acoustic pressure between 3 subresonance frequencies is also in 80dB or more.To have the advantages that in comparatively wide frequency range Interior, acoustic pressure rises and acoustic pressure difference becomes smaller, even if sound is also flat in the case where making sound frequency sweep.

In addition, the case where being at identical conditions 2mm and 3mm for the thickness of louver, tests, it can be with The thickness of confirmation louver does not influence the variation of acoustic pressure.In addition, if L1/W1 is that 1.40~1.45, L2/L1 is 0.45~0.55, W2/W1 are 0.55~0.59, then obtain acoustic pressure-frequency characteristic same as the example of Figure 22 (C) to (E).

Industrial utilization possibility

According to the present invention, even if the place big in noise, is also capable of providing the piezoelectricity that can hear the sound of multiple scales Sound part.

Description of symbols

1 piezoelectricity sound part

3 downside case halfs

4 louvers

5 upside case halfs

6 shells

7 opening portions

7A long side

7B short side

The protrusion 7C

9 pronunciation component retainers

11 piezoelectricity pronunciation components

12 oscillating plates

13 on-fixed portions

13A long side

13B short side

13C recess portion

13Ca parallel lines portion

13Cb angled straight lines portion

15 piezoelectric elements

The straight line portion 15A

The bending section 15B

31 bottom wall parts

32 peripheral wall portions

51 upper wall portions

52 peripheral wall portions

The first imaginary line of PL1

The second imaginary line of PL2

The first space S1

S2 second space