JPH1165570A - Sound-producing body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To assure a large sound pressure to be adopted for a portable telephone set or a pager, etc., by forming a sound-producing body in such a manner that a metallic plate is bent largely for assuring a large sound pressure by a piezoelectric effect and the excitation effect of a coil disposed at the metallic plate for the purpose of generating the sounds of the large sound pressure and to utilize this coil for the purpose of vibration generation as well. SOLUTION: A piezoelectric diaphragm 1, consisting of a piezoelectric element 2 and a metal plate 3, is provided with a coil 4 to be excited by inputting of pulse waves. The electrode of the piezoelectric element 2 and the terminal of the coil 4 are electrically connected. A stator 5 is fixed to a leaf spring 9. The coil 4 is inserted into the magnetic circuit of the stator 5. An excitation part B is formed by the stator 5 and the leaf spring 9.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a sounding body.

[0002]

2. Description of the Related Art Japanese Patent Application Laid-Open No. 7-203590 discloses a piezoelectric sounding body as a sounding body for generating a ring tone used in a mobile phone or a pager. It is described in Japanese Utility Model Laid-Open No. 57-46887. The former piezoelectric sounding body generates sound by generating distortion in a metal plate using the piezoelectric effect of piezoelectric ceramic, and the latter moving coil sounding body is a magnetic circuit of a stator using a magnet. The sound is generated by vibrating the metal plate to which the coil is fixed by utilizing the function of (1).

[0003]

However, it has not been possible to secure a sufficient sound pressure with the above two conventional sounding bodies. In addition, any mobile phone or pager using these sounding bodies can only notify the incoming call by sound, and in order to be able to notify the incoming call by vibration, the above sounding body is called Separately, it is necessary to provide a vibrating mechanism using a motor or the like, and in such a case, there is a problem that the entire size of the sounding body and the vibrating mechanism must be large.

[0004] The present invention has been made under the above circumstances, and a sounding body capable of securing a large sound pressure by making a metal plate bend greatly by a piezoelectric effect and an exciting effect of a coil. The purpose is to provide.

Further, the present invention provides a coil provided on the metal plate for generating a sound with a large sound pressure so that the coil can be used for generating a vibration. An object of the present invention is to provide a sounding body capable of notifying an incoming call.

A further object of the present invention is to reduce the size of a sounding body capable of notifying an incoming call by sound or vibration and to reduce the installation space thereof.

[0007]

According to a first aspect of the present invention, there is provided a sounding body comprising a piezoelectric element comprising a piezoelectric element having electrodes formed on both sides of a piezoelectric ceramic for applying a voltage to the piezoelectric ceramic, and a metal plate. A coil that is excited by applying a voltage is provided on the metal plate of the diaphragm.

[0008] In the present invention, the sound generating portion is formed by the piezoelectric vibrating plate having the piezoelectric element and the coil. In the present invention, when a voltage is simultaneously applied to both the piezoelectric element and the coil, the metal plate forming the piezoelectric vibrating plate includes:
Since the distortion associated with the piezoelectric action of the piezoelectric element and the vibration associated with the excitation of the coil occur simultaneously, the metal plate is greatly bent, and a large sound pressure is obtained. That is, when a pulse wave is input to the coil, a magnetomotive force is generated in the coil, and the magnetomotive force and the above-described piezoelectric action act synergistically to bend the metal plate greatly to obtain a large sound pressure.

The sounding body according to the second aspect of the present invention is the first aspect.
In the above, the electrode on one side of the piezoelectric element and the terminal on one side of the coil are electrically connected, and the electrode on the other side of the piezoelectric element and the other side of the coil on the other side. The terminal is electrically connected.

According to the present invention, the wiring for applying a voltage to the piezoelectric element and the wiring for applying a voltage to the coil are shared, so that the wiring is simplified.

The sounding body of the invention according to claim 3 is the sounding body according to claim 1.
Alternatively, a stator that forms a magnetic circuit is fixed to an elastic body by a magnet and a pole plate provided on a magnetic pole of the magnet, and the coil is inserted into the magnetic circuit of the stator. It is that.

In the present invention, a sound generating portion is formed by a piezoelectric vibrating plate having a piezoelectric element and a coil, a vibrating portion is formed by a stator and an elastic body, and the coil is used to vibrate the vibrating portion. Is helpful. That is, according to the present invention, the magnetomotive force generated in the coil provided on the metal plate for generating a sound with a large sound pressure generates kinetic energy of suction repulsion in the stator, and the stator vibrates. Therefore, a sounding body that can generate vibration without providing a special vibration generating device is configured.

[0013] A leaf spring can be used for the elastic body as in the invention according to claim 4, in which case the leaf springs are arranged in the circumferential direction as in the invention according to claim 5. It is desirable to have a plurality of arc-shaped slits. If such a leaf spring is used for the elastic body to which the stator is fixed, not only can the amplitude of the stator be secured large, but also the leaf spring itself does not take up space because it is not bulky. Helps to reduce body size.

According to a sixth aspect of the present invention, there is provided a sounding body according to any one of the third, fourth, and fifth aspects, wherein the coil, the piezoelectric diaphragm having the coil, An elastic body and the stator fixed to the elastic body are provided concentrically inside a cylindrical case. According to a seventh aspect of the present invention, in the sounding body according to the sixth aspect, the case has a first cover portion provided with a sound hole on one end side, and a second cover portion on the other end side of the case. Parts. Here, the first cover portion may be formed integrally with the case or may be formed separately. Similarly, the second cover part may be formed integrally with the case or may be formed separately. The sounding body of the invention according to claim 8 is the sounding body according to claim 7.
Wherein two terminals protrude through the body wall of the case, and one of the terminals is connected to the electrode on one side of the piezoelectric element and the terminal on one side of the coil. Part is electrically connected, and the other terminal is electrically connected to a connection between the electrode on the other side of the piezoelectric element and the terminal on the other side of the coil. is there.

According to these inventions, the sounding body capable of notifying the incoming call by sound or vibration is downsized, so that the installation space can be reduced. Therefore, a mobile phone or a pager using such a sounding body is provided. The miniaturization of is promoted. In particular, in the case where the terminal is protruded from the body wall of the case as in the invention according to claim 8, the attachment to a mobile phone or a pager is improved, and the replacement can be easily performed.

According to a ninth aspect of the present invention, there is provided the sounding body according to any one of the third, fourth, fifth, sixth, seventh and eighth aspects. Input frequency to the high frequency band 2 to 4 kHz
In the high frequency band, the piezoelectric vibrating plate causes resonance, the stator and the elastic body do not follow the input, and in the low frequency region, the piezoelectric vibrating plate does not operate. Without resonance, the stator and the elastic body follow the input operation. According to the present invention, 30 to 2
In the low frequency band of 00 Hz, the piezoelectric diaphragm does not resonate and no loud sound is generated. Therefore, it is possible to notify the incoming call only by the vibration. On the other hand, in the high frequency band of 2 to 4 kHz, the stator and the elastic body are input. Since it is no longer possible to follow up and does not vibrate, it is possible to notify an incoming call only by sound.

[0017]

FIG. 1 is a longitudinal sectional view showing one embodiment of a sounding body according to the present invention. This sounding body has a function of notifying an incoming call by sound or vibration, and includes a sound generating unit A that generates a sound and a vibrating unit B that generates a vibration.

The sound generator A comprises a piezoelectric diaphragm 1 and a coil 4. The piezoelectric vibration plate 1 is formed by holding a disk-shaped piezoelectric element 2 formed by forming electrodes on both front and back surfaces of a piezoelectric ceramic at the center of the upper surface of a disk-shaped thin metal plate 3 by bonding or the like. ing. The electrode on the lower surface side of the piezoelectric element 2 is electrically connected to the metal plate 3. The coil 4 is formed in a cylindrical shape,
It is fixed at a concentric position on the lower surface of the metal plate 3. As a mode of fixing the coil 4 to the metal plate 3, as shown in FIG. 1, an insulating sheet 31 made of a synthetic resin is bonded and held on the metal plate 3, and the coil 4 is bonded and held on the insulating sheet 31. Is possible, but in some cases the insulating sheet 3
1 may be omitted and the coil 4 may be directly adhered to the metal plate 3 and held. The coil 4 shown in FIG. 1 is formed by winding a thin conductor by a predetermined number of turns and keeping the shape of a coil. Although it does not have a bobbin, as shown in FIG. Can be used as the coil 4 having a predetermined number of turns. Coil 4 and insulating sheet 31
As an adhesive for adhering to the metal plate 3, an epoxy resin-based or acrylic resin-based adhesive can be suitably used.

The electrode on one side of the piezoelectric element 2 and the terminal on one side of the coil 4 are electrically connected.
And the other end of the coil 4 are also electrically connected. As one specific example of this connection, as shown in FIG. 4 or FIG. 5, a lead wire 21 is soldered to one electrode of the piezoelectric element 2 formed on the upper surface of the piezoelectric ceramic, and the lead wire 21 is soldered. Is the terminal 4 on one side of the coil 4
2 and connected to the metal plate 3 electrically connected to one electrode of the piezoelectric element 2 formed on the lower surface of the piezoelectric ceramic, and another lead wire 22 is soldered thereto. Then, the lead wire 22 is connected to the terminal 4 on the other side of the coil 4.
3 (soldering). Reference numerals 44 and 45 indicate respective connection portions. By adopting such a connection method, the wiring for applying a voltage to the piezoelectric element 2 and the coil 4 can be simplified, the number of parts of the sounding body can be reduced, and the sounding body can be downsized. It is useful to do. FIG. 5 illustrates an example in which the coil 4 is directly bonded to the metal plate 3. As another specific example of the above connection, as shown in FIG. 6, a contact 23 made of a thin metal piece having elasticity is elastically contacted with one electrode of the piezoelectric element 2 formed on the upper surface of the piezoelectric ceramic. Another contact 24 is elastically contacted with the metal plate 3 electrically connected to the other electrode, and each of the contacts 23 and 24 is connected to the terminal 42 on one side of the coil 4 described with reference to FIG. And the terminal 43 on the other side.

The vibrating portion B is composed of a stator 5 having a circular shape in plan view and a leaf spring 9 having a disk shape. Stator 5
Includes a disk-shaped magnet 6 magnetized in the thrust direction, a yoke (pole plate) 7 provided on one magnetic pole of the magnet,
It is formed by a pole piece (pole plate) 8 provided on the other magnetic pole of the magnet. The pedestal 71 provided on the yoke 7 of the stator 5 is fixed to the center of the upper surface of the leaf spring 9 by using an appropriate means such as adhesion. The coil 4 of the sound generating section A is inserted into a gap 51 formed between the yoke 7 of the stator 5 and the pole piece 8. With this configuration, the coil 4 is inserted into the magnetic circuit of the stator 5. As shown in FIG.
Has a plurality of (three in the example in the figure) arc-shaped slits 91 arranged in the circumferential direction, and the central portion 92 of the leaf spring 9 surrounded by the inner ends of these slits 91 The pedestal 71 of the yoke 7 is fixed. For this reason, the stator 5 fixed to the leaf spring 9 is
Can swing up and down with a small force.

The coil 4 forming the above-mentioned sound generating portion A
, The piezoelectric vibrating plate 1, and the leaf spring 9 and the stator 5 forming the vibrating portion B are concentrically arranged inside a cylindrical case 100 made of a synthetic resin and having both ends opened. . An opening 110 at one end of the case 100
A metal first cover 200 having a sound hole 201 is attached to the case 100.
The second cover part 300 made of metal is mounted on the first cover. Two terminals (only one terminal is shown in FIG. 1) 400 are protruded side by side through the body wall 130 of the case 100, and these terminals 400 are described with reference to FIG. The two connecting portions 44 and 45 are electrically connected to each other. In this embodiment, the first cover part 200 is formed by a member different from the case 100, and
Although the cover part 200 is attached to the opening 110 on one end side of the case 100, the first cover part 200 has the bottom
May be used as the first cover part 200 and the sound hole 201 may be provided therein. The same applies to the second cover 300, and a portion corresponding to the second cover 300 may be formed integrally with the case 100. First
When the cover part 200 and the second cover part 300 are formed integrally with the case 100, the first cover part 200 and the second cover part 300 are made of the same material as the case 100, that is, if the case 100 is made of synthetic resin, The first cover 200 and the second cover 300 are formed of a synthetic resin. The first cover 200 and the second cover 300
Are integrally illustrated with the case 100 are not shown.

FIG. 2 is a longitudinal sectional view showing another embodiment of the sounding body according to the present invention. In this sounding body, a magnet 6 of a stator 5 is formed in a ring shape magnetized in a radial direction, and a yoke 7 provided on a magnetic pole on one side of the magnet 6 and a magnetic pole on the other side of the magnet 6 1 is different from the sounding body of FIG. 1 only in that the coil 4 of the sounding section A is inserted into a gap 52 formed between the sounding body A and FIG. 1 and FIGS. This is the same as described above. Therefore, the same or corresponding parts are denoted by the same reference numerals, and detailed description will be omitted. In addition,
With the configuration in which the coil 4 is inserted into the gap 52, the coil 4 is inserted into the magnetic circuit of the stator 5.

In the sounding body described with reference to FIGS. 1 and 2,
The input frequencies to the piezoelectric element 2 and the coil 4 are classified into a high frequency band of 2 to 4 kHz and a low frequency region of 30 to 200 Hz. Then, in the high frequency band, the piezoelectric diaphragm 1 forming the sound generating portion A resonates, and the stator 5 and the plate spring 9 forming the vibrating portion B do not follow the input. In the region, the piezoelectric vibrating plate 1 forming the sound generating portion A does not resonate, and the stator 5 and the plate spring 9 forming the vibrating portion B follow the input.

For this reason, the piezoelectric element 2
When the frequency of the high frequency band of 2 to 4 kHz is input to the coil 4 at the same time, the metal plate 3 forming the piezoelectric vibration plate 1 of the sound generating section A receives the distortion caused by the piezoelectric action of the piezoelectric element 2 and the coil 4. Since vibration accompanying excitation (vibration caused by magnetomotive force generated when a pulse wave is input to the coil) occurs at the same time, the metal plate 3 is largely bent to obtain a large sound pressure. The sound pressure at this time was as large as 75 dB compared to 65 dB when only the piezoelectric effect was used. When a frequency in a high frequency band of 2 to 4 kHz is input, the stator 5 and the leaf spring 9 of the vibrating section B are
There is no vibration because the operation cannot follow the input much. Therefore, at this time, the incoming call is notified only by the sound.

On the other hand, when a low frequency band of 30 to 200 Hz is simultaneously input to the piezoelectric element 2 and the coil 4 via the terminal 400, the piezoelectric diaphragm 1 of the sounding section A does not resonate,
Since the stator 5 and the leaf spring 9 of the vibrator B follow the input, no loud noise is generated, and the incoming call is notified only by the vibration.

In the sounding body of the present invention, an elastic part such as a rubber plate or a coil spring can be used instead of the leaf spring 9 of the vibrating portion B. However, if the leaf spring 9 is used as in the above-described embodiment, the leaf spring 9 itself is less bulky than a rubber plate or a coil spring. It is advantageous to use the leaf spring 9 in the formation.

By the way, when a mobile phone or a pager is provided with a sounding body and only the mobile phone or the pager is required to have a function of notifying an incoming call by sound, FIGS. It is only necessary to employ a sounding body having only the sounding section A described in the above, and it is not necessary to necessarily adopt a sounding body having both the sounding section A and the vibration section B.

Further, in the sounding body described with reference to FIGS. 1 and 2, it is possible to apply a voltage to the sounding section A and the vibrating section B by separate circuits.

[0029]

In the sounding body according to the first aspect of the present invention, since the metal plate is greatly bent by the piezoelectric effect and the exciting effect of the coil, only the piezoelectric effect or only the exciting effect of the coil is used. It becomes possible to secure a large sound pressure as compared with a sounded body.

In the sounding body according to the third aspect of the present invention, the coil forming the sounding portion is also used as the vibrating portion.
Despite no special vibration mechanism, the incoming call can be notified by sound or vibration. Therefore, in a mobile phone, a pager, or the like that requires a sounding body capable of notifying an incoming call by sound or vibration, the number of parts of the sounding body is reduced, so that the size can be easily reduced and the installation space can be reduced. Will also help to keep it small.

In the sounding body according to the sixth and seventh aspects of the invention, the coil forming the sounding portion is also used as the vibrating portion, and the sounding portion and the vibrating portion are common to them. Because it is installed in a cylindrical case, the sounding body that can notify the incoming call by sound or vibration is downsized, the installation space is kept small, and a mobile phone or pager using such a sounding body It is easy to promote downsizing.
The miniaturization of the sounding body is particularly promoted by the invention according to claim 2 and the inventions according to claims 4 and 5 using a non-bulky leaf spring for the elastic body.

In the sounding body of the invention according to the eighth aspect, the terminal is projected from the body wall of the case in which the sounding portion and the vibrating portion are provided, so that the attachment to a mobile phone or a pager is improved. There is an advantage that the replacement can be easily performed.

In the sounding body according to the ninth aspect of the present invention, the input frequency is simply switched between the high frequency band and the low frequency band.
Since the notification of the incoming call only with the sound and the notification of the incoming call only with the vibration are selectively performed, it is possible to suitably employ the mobile phone and the pager.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing one embodiment of a sounding body according to the present invention.

FIG. 2 is a longitudinal sectional view showing another embodiment of the sounding body according to the present invention.

FIG. 3 is an explanatory diagram of a state where a modified example of a coil is attached to a piezoelectric diaphragm.

FIG. 4 is an explanatory diagram showing a connection state of a lead wire to a piezoelectric element in a plan view.

FIG. 5 is an explanatory diagram showing a connection state between a piezoelectric element and a coil in a side view.

FIG. 6 is an explanatory diagram showing a connection state of a contact to a piezoelectric element in a plan view.

FIG. 7 is a plan view of a leaf spring.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Piezoelectric vibration plate 2 Piezoelectric element 3 Metal plate 4 Coil 5 Stator 6 Magnet 7 Yoke (polar plate) 8 Pole piece (polar plate) 9 Plate spring (elastic body) 44, 45 Connection part 91 Slit 100 Case 110, 120 Opening 130 Case wall 201 Sound hole 200 First cover 300 Second cover 400 Terminal

Claims (9)

[Claims] An excitation is performed by applying a voltage to a metal plate of a piezoelectric vibration plate composed of a metal plate and a piezoelectric element in which electrodes for applying a voltage to the piezoelectric ceramic are formed on both surfaces of the piezoelectric ceramic. A sounding body characterized by being provided with a coil to be formed. 2. The electrode on one side of the piezoelectric element and the terminal on one side of the coil are electrically connected, and the electrode on the other side of the piezoelectric element and the terminal on the other side of the coil. 2. The sounding body according to claim 1, wherein the sound generator is electrically connected to the sound generator. 3. A stator, which forms a magnetic circuit by a magnet and a pole plate provided on a magnetic pole of the magnet, is fixed to an elastic body, and the coil is inserted into the magnetic circuit of the stator. The sounding body according to claim 1 or 2. 4. The sounding body according to claim 3, wherein said elastic body is a leaf spring. 5. The sounding body according to claim 3, wherein a plurality of arc-shaped slits arranged in a circumferential direction are formed in the leaf spring. 6. The coil, the piezoelectric vibrating plate provided with the coil, the elastic body, and the stator fixed to the elastic body are arranged concentrically inside a cylindrical case. The sounding body according to any one of claims 3, 4, and 5. 7. The sounding body according to claim 6, wherein the case has a first cover portion provided with a sound hole on one end side, and a second cover portion on the other end side of the case. 8. A terminal is provided with two terminals protruding through the body wall of the case, and one terminal of the terminal is connected to the electrode on one side of the piezoelectric element and the terminal on one side of the coil. 8. The electrical connection of claim 7, wherein the other terminal is electrically connected to a connection between the electrode on the other side of the piezoelectric element and the terminal on the other side of the coil. Sounding body. 9. An input frequency to the piezoelectric element and the coil is set to a high frequency band of 2 to 4 kHz and a low frequency region of 30 to 20.
0 Hz, the piezoelectric vibrating plate resonates in the high frequency band, the stator and the elastic body do not follow the input, and the piezoelectric vibrating plate does not resonate in the low frequency region, The sounding body according to any one of claims 3, 4, 5, 5, 6, 7, and 8, wherein the elastic body is configured to follow an input.