JP2003062525A - Electromagnetic actuator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electromagnetic actuator capable of obtaining stable vibration and excellent sound. SOLUTION: This electromagnetic actuator is equipped with a vibration coil 3 to which a low-frequency current is applied, a vibration unit 10, a case 13 for storing these and supporting the vibration coil 3, a diaphragm 23 covering the case 13, a voice coil 5 which is supported by the diaphragm 23 opposing to the vibration coil 3 and to which a high-frequency current is applied, and upper and lower springs 15, 17 supporting the vibration unit 10 against the case 13. The vibration unit 10 is equipped with a magnet 7 arranged by providing a gap in the radial direction for positioning the vibration coil 3 and the voice coil 5, and a yoke 9 unified with this magnet 7. The magnet 7 is arranged in the outer periphery side of the vibration unit 10. Application of the low-frequency current to the vibration coil 3 vibrates the vibration unit 10, and application of the high-frequency current to the voice coil 5 vibrates the diaphragm 23.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electromagnetic actuator used for a mobile phone, a pager, etc. for notifying a call when a signal arrives by vibrating or sounding.

[0002]

2. Description of the Related Art As this type of electromagnetic actuator, the one disclosed in WO99 / 39843 is known. This electromagnetic actuator is shown in FIG. As shown in FIG. 7, in the electromagnetic actuator 100, the magnet 105 is arranged in the groove portion of the yoke 103 in the case 101, and the coil 109 is located in the groove portion through the gap with the magnet 105 and attached to the diaphragm 107. Is provided, and the yoke 103 is
Upper and lower diaphragms 11 arranged in parallel to the side surface of the casing 101.
It is supported by 1, 113. By applying a low frequency current to the coil 109, the vibration plates 111, 113
Of the diaphragm 107 by vibrating the yoke 103 and applying a high frequency current to the coil 109.
To generate high frequency sound. Also, the case 10
The flange 115 is arranged from 1 toward the inner radial direction to regulate the vibration direction of the yoke 103 in the vertical direction.

[0003]

However, in the above-mentioned technique, since the coil 109 is attached to the diaphragm 107, the diaphragm 107 vibrates even when driven by a low frequency current, and a sufficient vibration output is obtained. There is a problem that you cannot get it. On the other hand, if the rigidity of the diaphragm 107 is controlled in order to obtain a sufficient vibration output, there is a problem that the frequency band of the diaphragm 107 that naturally vibrates in the audible frequency band is limited and a good sound cannot be obtained.

Further, when the brim 115 for regulating the vibration direction comes into contact with the yoke 103, there is a problem that stable vibration is impaired due to contact friction.

Therefore, an object of the present invention is to provide an electromagnetic actuator which can obtain stable vibration and good sound.

[0006]

According to a first aspect of the present invention, there is provided a vibrating coil to which a low frequency current is applied, a vibrating unit, a case that houses these and supports the vibrating coil, and a case. The vibrating unit includes a diaphragm for covering, a voice coil supported by the diaphragm so as to face the vibrating coil and to which a high-frequency current is applied, and an elastic body for supporting the vibrating unit with respect to the case. A magnet arranged with a radial gap for positioning the coil and a yoke integrated with the magnet are provided, and the magnet is arranged on the outer peripheral side of the vibration unit and the yoke is arranged on the inner peripheral side of the vibration unit. The vibration unit vibrates when a low frequency current is applied to the vibration coil, and the diaphragm unit is applied when a high frequency current is applied to the voice coil. There characterized by vibration.

According to the first aspect of the present invention, a magnetic field is formed in both the vibration coil and the voice coil which are located opposite to each other, and a low frequency current (for example, 10) is generated in the vibration coil.
(0 to 150 Hz), the vibration unit vibrates (the yoke and the magnet vibrate together) due to the action of the low-frequency current and the magnetic field on the vibration coil side, which causes vibration from the electromagnetic actuator. To do. Similarly, a high frequency current (for example, 900 to 80) is applied to the voice coil.
(00 Hz), the action of this high-frequency current and the magnetic field on the voice coil side causes the diaphragm to vibrate, and a sound is generated from the electromagnetic actuator.

The vibrating coil is supported by a fixed case, and the vibrating unit is supported by the case via an elastic body, so that stable vibration can be obtained. Further, both a vibration system including a vibration coil for applying a low frequency current and a vibration unit for low frequency vibration and a vibration system including a voice coil for applying a high frequency current and a diaphragm for high frequency vibration are provided. By doing so, each can be designed independently, so that each efficiency can be increased to the maximum value, and sufficient vibration output and good sound can be obtained. In addition, since the voice coil and the vibration coil are arranged with a gap provided on the front and back surfaces (upper and lower surfaces in the figure) of the electromagnetic actuator, the radius of both coils can be freely designed and sufficient vibration output can be obtained. You can get a good quality tone.

Further, since the magnet is arranged on the outer peripheral side of the vibration unit, the volume of the magnet can be increased and the strength of the magnetic field in the gap portion can be increased, so that the output level of vibration and sound can be increased.

According to a second aspect of the present invention, a vibration coil to which a low frequency current is applied, a vibration unit, a case that houses these and supports the vibration coil, a diaphragm that covers the case, and a diaphragm are provided. The vibration unit includes a voice coil that is supported to face the vibration coil and to which a high frequency current is applied, and an elastic body that supports the vibration unit with respect to the case. And a yoke integrated with the magnet, the yoke is arranged on the outer peripheral side of the vibrating unit and the magnet is arranged on the inner peripheral side of the vibrating unit. The vibration unit vibrates when a low frequency current is applied to the coil, and the diaphragm vibrates when a high frequency current is applied to the voice coil. And it features.

According to the second aspect of the present invention, the yoke is arranged on the outer peripheral side of the vibrating unit and the magnet is arranged on the inner peripheral side of the vibrating unit, so that the leakage magnetic flux from the magnet to the surrounding space is suppressed to a small level. The influence of magnetic noise on external parts can be reduced.

The invention according to claim 3 is the invention according to claim 1 or 2.
In any one of the inventions described above, the elastic body is provided with a collar at every 120 ° on the outer circumference, and is fixed to a groove provided on the inner circumferential surface of the case to support two vibration units from above and below. Characterized by being a spring

According to the third aspect of the invention, since the case can be formed as an integrated structure, the vibration unit can be firmly fixed to the case.

The invention according to a fourth aspect is the first to the third aspects.
In any one of the inventions described above, a shaft for supporting the vibration unit slidably in the vibration direction is provided.

According to the invention of claim 4, claim 1
The same effect as the invention described in any one of 1 to 3 is provided, and by providing a shaft that slidably supports the vibrating unit in the vibrating direction, an external impact to the electromagnetic actuator, for example, an impact at the time of dropping. Even if there is, the position of the vibration unit can be prevented from being displaced in the radial direction of the voice coil, and the shock resistance is improved. Also,
Even if the electromagnetic actuator is placed in any direction, the vibration unit slides smoothly in the axial direction, so that more stable vibration can be obtained.

[0016]

DETAILED DESCRIPTION OF THE INVENTION Embodiments of the present invention will be described in detail below with reference to the accompanying drawings. 1 is a sectional view showing an electromagnetic actuator according to the present invention, FIG. 2 is an exploded perspective view of the electromagnetic actuator of FIG. 1, and FIG. 3 is a plan view of a spring used for an elastic body of the present invention. FIG. 4 is a cross-sectional view showing an example of mounting the electromagnetic actuator in the mobile phone. The electromagnetic actuator 1 shown in FIG. 1 notifies a user of information received through a mobile phone by vibrating or sounding.

The electromagnetic actuator 1 includes a vibration coil 3 to which a low frequency current is applied and magnets 7-1 and 7-.
2, magnetic material yoke 9, and pole pieces 31-1, 31-
2, a case 13 for housing them, and a vibration unit 10 for the case 13.
Lower spring 17 that supports the lower surface of the vibration unit 10 and upper spring 1 that supports the upper surface of the vibration unit 10 with respect to the case 13.
5, a diaphragm 23 that is a diaphragm whose periphery is fixed on the circumferential end surface of the upper ring 40, and a voice coil 5 that is fixed on a ring-shaped protrusion 23a of the diaphragm 23 and to which a high-frequency current is applied. Vibration coil 3 in case 13
And a lower ring 41 that is supported and fixed from the lower surface of
By applying a low-frequency current to the vibration coil 3, the vibration unit 10 forms the shaft 1 that is a part of the case 13.
By vibrating in the axial direction of 3d (vertical direction in FIG. 1) and applying a high-frequency current to the voice coil 5, the diaphragm 23 vibrates and sounds. In the present specification, the terms above and below are used for convenience,
This does not specify the vertical direction.

The case 13 is provided with an annular groove portion 13a for fixing the lower ring 41 by adhesion, a linear groove portion 13b for drawing out the lead wire 3a of the vibration coil 3 to the outside, and a plurality of holes 13c for letting out fluctuating internal air pressure. A shaft portion 13d protruding upward in the central portion of the lower surface, a terminal portion 13e in one angular direction of the outer peripheral surface, and three groove portions 13f formed from above every 120 ° on the inner peripheral surface, 60 with groove 13f
It is provided with three groove portions 13g formed from above at intervals of 120 °. The groove 13f is a shallow groove that is horizontal with the upper surface of the vibration unit 10, and the groove 13g is a deep groove that is horizontal with the lower surface of the vibration unit 10.

The three flanges 17a of the lower spring 17 are fixed (adhered) to the lower surface of the groove 13g, and the vibration unit 1
0 supports the lower surface of the upper spring 15 and three flanges 15a of the upper spring 15.
Is fixed (bonded) to the lower surface of the groove 13f to support the upper surface of the vibration unit 10, and the lower spring 17 and the pole piece 31-2 and the upper spring 15 and the pole piece 31-1 are bonded and fixed. ing. The resonance frequency of the vibration system including the spring coefficients of the upper and lower springs 15 and 17 and the mass of the vibration unit 10 is set to match the frequency of the low-frequency current applied to the vibration coil 3.

In this embodiment, the upper and lower springs 15 and 17, which are elastic bodies, are leaf springs as shown in FIG. 3, and the collars 15a and 17a are provided for adhesion and fixing to the case 13. The inner peripheral portions 15b and 17b are provided for adhesive fixing to the pole pieces 31-1 and 31-2, respectively.

The diaphragm 23 is formed by molding a thin film of a high molecular compound such as polyethylene into a disc shape, and is adhered and fixed to the upper surface circumferential portion of the upper ring 40, and the lower surface of the upper ring 40 is of the case 13. It is adhesively fixed to the circumference of the upper surface. Further, in order to obtain a flat natural vibration characteristic in a wide frequency band, a plurality of cone-shaped moldings are performed, and a portion to which the voice coil 5 is bonded is formed as a projection 23a by projecting in a ring shape. ing. This protrusion 23a is
It is projected toward the gap between the yoke 9 and the magnet 7, and is provided in order to avoid collision with the diaphragm 23 when the vibration unit 10 vibrates in the vertical direction. In addition, in the small electromagnetic actuator 1,
The intrinsic fundamental (minimum) frequency of the diaphragm 23 is 1 kHz
The current applied to the voice coil 5 is called a high frequency current because it has a high frequency near z.

The yoke 9 has a central portion 27 having an insertion hole 27a for inserting the shaft portion 13d, and a central portion 27.
And a joint portion 29 that is widened in the outer peripheral direction. The yoke 9 is slidable in the axial direction of the shaft portion 13d by the shaft portion 13d inserted through the insertion hole 27a of the central portion 27.

By providing the shaft portion 13d that slidably supports the yoke 9, even when an external impact is applied to the electromagnetic actuator 1, such as when the electromagnetic actuator 1 is dropped, the yoke is Position 9 is toward the outer circumference (toward the left and right in FIG. 1)
The displacement can be prevented, the shock resistance is improved, and the vibration direction of the vibration unit 10 is regulated in the axial direction.

A magnet 7-1 and a pole piece 31-made of a magnetic material are provided above the joint 29 of the yoke 9.
1 are arranged in this order, and the magnet 7-2 and the pole piece 31-2 made of a magnetic material are arranged below in this order. The magnets 7-1 and 7-2 and the pole pieces 31-1 and 31-2 are bonded and fixed to the outer peripheral surface of the joint portion 29, and the pole pieces 31-1 and 31-2.
-2 and the central portion 27 of the yoke 9 form an upper magnetic gap 35a and a lower magnetic gap 35b.

The voice coil 5 is arranged in the upper magnetic gap 35a, and the vibration coil 3 is arranged in the lower magnetic gap 35b. The vibration coil 3 and the voice coil 5 are provided so as to face each other. There is. The lower ring 41 is provided to position the vibration coil 3 in the center of the lower magnetic gap 35b, and
This prevents the bottom surface of the case 13 from colliding with each other when it vibrates up and down. Further, the joining portion 29 and the voice coil 5
Also, a gap with the vibration coil 3 is provided for collision prevention.

The lead wire 5a of the voice coil 5 is bonded to the lower surface of the diaphragm 23 and is connected to the terminal portion 13e through the joint surface with the upper ring 40, and the lead 3a of the vibration coil 3 is linear. Terminal portion 13 through groove portion 13b
connected to e. High-frequency and low-frequency currents are supplied to these terminals from inside the mobile phone.

As shown in FIG. 4, the electromagnetic actuator 1 is sandwiched between the substrate 4 and the housing 6 inside the mobile phone by sandwiching the upper and lower circumferential end faces with annular seats 2 made of a material such as plastic. Fix it. The substrate 4 is provided with a ventilation hole 4a, and the housing 6 is provided with an acoustic radiation hole 6a, which is provided with an escape port for the internal air that vibrates in compression and the electromagnetic actuator 1 is provided.
The case 13 of is fixed to the mobile phone.

In this embodiment, the magnet 7-1 is
Since the junction surface with the pole piece 31-1 is the N pole and the junction surface with the junction 29 is the N pole, the magnet 7-2 has a magnetic field that circulates from the upper magnetic gap 35a to the lower magnetic gap 35b. Forming a road. The vibration unit 10 includes a central portion 27 of the yoke 9, magnets 7-1 and 7-2, and pole pieces 31-1 and 31-2.
Are integrated via a joint portion 29 and are slidable in the axial direction of the shaft portion 13d.

The outer circumferences of the pole pieces 31-1 and 31-2 cover the inner diameters of the ring-shaped magnets 7-1 and 7-2 up to about three quarters, and the inner circumferences of the voice coils 5 and the vibration. The joint 29 side of the surface facing the coil 3 is deleted to reduce the vertical width of the upper and lower magnetic gaps 35a and 35b.

Next, the operation of this embodiment will be described based on the above-mentioned configuration. To assemble the electromagnetic actuator 1, after bonding the vibration coil 3 on the lower ring 41, the lower ring 41 is bonded to the case 13, and the lead wire 3a of the vibration coil 3 is passed through the linear groove portion 13b and the terminal portion. Connect to 13e. Next, the yoke 9 and the magnet 7-
1, 7-2 and the pole pieces 31-1, 31-2 are fixed (adhered) to assemble the vibration unit 10. Subsequently, the upper spring 15 is fixed to the upper surface of the vibration unit 10 and the lower spring 17 is fixed to the lower surface (adhesion).

The unit in which the vibration unit 10 and the upper and lower springs 15 and 17 are integrally fixed is inserted into the case 13 while the central portion 27 is inserted through the shaft portion 13d.
And is adhered (bonded) to the lower surfaces of the groove portions 13g and 13f. Next, the upper ring 40 is bonded to the upper surface circumferential portion of the case 13. The voice coil 5 is adhered to the lower surface of the diaphragm 23 in advance, and at the same time, the lead wire 5a for the voice coil is provided to the outside while adhering to the lower surface of the diaphragm 23. Finally, the diaphragm 23 having the voice coil 5 attached thereto is bonded to the upper surface circumferential portion of the upper ring 40, and at the same time, the lead wire is connected to the terminal portion 13e.

In this electromagnetic type actuator 1, when a low frequency current (a single frequency of 100 to 150 Hz as a sensible frequency, for example) is applied to the vibration coil 3 from a circuit in the mobile phone, the low frequency current is applied. And the magnetic field of the lower magnetic gap 35b cause the vibration unit 10 to
It vibrates in the axial direction of the shaft portion 13d. When the vibration unit 10 vibrates, the mobile phone holding the case 13 vibrates and transmits information such as an incoming signal to the wearer.

In this embodiment, the vibration unit 10
The resonance frequency of the oscillating system consisting of the mass and the upper and lower springs 15 and 17 is matched with the frequency of the supplied low-frequency current to make the transfer of electromagnetic energy to kinetic energy efficient. The joint portion 29 of the yoke 9 has a role of increasing the mass of the vibration unit 10 and also a role of supporting an attraction force between the upper and lower magnetic gaps 35a and 35b.

When a high frequency current (a broadband frequency of 900 to 8000 Hz as an audible frequency) is applied to the voice coil 5, the high frequency current and the magnetic field of the upper magnetic gap 35a cause the diaphragm 23 to generate a high frequency. Causes band vibration. Since the diaphragm 23 is a diaphragm formed of a thin film material such as polyethylene in a cone shape, it faithfully radiates acoustic waves with respect to the driving force in the high frequency band via the voice coil 5. When the diaphragm 23 vibrates, the case 6 of the mobile phone holding the case 13 is fixed.
The high-frequency sound transmits information such as an incoming signal to the wearer through the sound radiation hole 6a.

In the present embodiment, the vibrating unit 10 is vibrated by the electromagnetic force of the vibration coil 3 fixed to the case 13 and the magnetic field of the lower magnetic gap 35b. That is, since the vibration system is formed independently of the vibration of the diaphragm 23, a stable vibration output can be obtained without being affected by the complicated vibration of the diaphragm 23 itself.

Here, regardless of the orientation of the mobile phone, the vibrating unit 10 must be moved in one direction in the vertical direction (axial direction), and a lateral impact is applied by an external factor. However, the vibrating unit 10 must be vibrated in the axial direction, but in the present embodiment, the shaft portion 13d is inserted through the center of the vibrating unit 10, so that the vibrating direction is stable in the axial direction with stable sliding friction. Can be regulated in any direction. Therefore, as in the case of providing the collar 115 on the case 101 shown in the conventional example of FIG.
The yoke 103 does not come into contact with each other, and no inconvenient phenomenon that hinders smooth vibration occurs.

Further, a vibration system including a vibration coil 3 for applying a low frequency current and a vibration unit 10 for low frequency vibration, a vibration system including a voice coil 5 for applying a high frequency current and a diaphragm 23 for high frequency vibration. Since two vibration systems are formed, the vibration coil 3 for low frequency vibration
And the voice coil 5 for the high frequency band acoustic system can be designed independently of each other, and the vibration output efficiency and the acoustic radiation efficiency can be respectively adjusted by designing the current drive circuit matched with each load characteristic. It can be increased up to the maximum value.

Further, if the vibration output efficiency and the sound radiation efficiency are designed to fall within appropriate ranges, the vibration coil 3 and the voice coil 5 are connected in series or in parallel, and one current drive circuit and one current drive circuit are connected. It is also possible to adopt a configuration having one load input (2 terminals). In this case, only one current drive circuit is required, and the number of connections with the mobile phone can be reduced to half. Since the pole pieces are omitted on the upper and lower surfaces of the outermost peripheral portion of the vibrating body 10, collision with the upper and lower springs 15 and 17 is avoided when the vibrating body 10 vibrates vertically. Further, the vertical widths of the magnetic gaps 35a and 35b are adjusted to optimum widths by cutting the vertical widths of the inner peripheral surfaces of the pole pieces 31-1 and 31-2 facing the yoke 9.

The present invention is not limited to the above-mentioned embodiments, and various modifications can be made without departing from the scope of the invention. For example, in the embodiment shown in FIG. 1, the joint portion 29 of the yoke 9 is largely expanded in the outer peripheral direction, and the two magnets 7-1 and 7-2 are fixed to the upper and lower surfaces of the outer periphery, but shown in FIG. As described above, if the side surfaces are fixed (adhered), the magnet 7 can be formed.

That is, in FIG. 5, the yoke 9 is provided with the central portion 27 and the joint portion 29. The joint portion 29 is fixed to the circumferential side surface of the annular magnet 7, and the vibration unit 1
0 is a magnet 7, a yoke 9, and a pole piece 31.
-1, 31-2. In the embodiment shown in FIG. 5, since the number of magnets used is one, it can be constructed at low cost.

Further, in the embodiment shown in FIG. 5, the joint portion 29 is a ring structure separate from the yoke 9, and the inner peripheral side surface is fixed (bonded) to the side surface of the central portion 27 of the yoke 9 and the dotted line portion shown in the figure. Then, the vibration unit 10 may be configured.
In this case, since the joint portion 29 is a portion unrelated to the magnetic path,
A non-magnetic material can be used.

In the embodiment shown in FIGS. 1 and 5, the magnet is arranged on the outer peripheral side and the yoke is arranged on the inner peripheral side. However, by reversing this, as shown in FIG.
The magnet 7 may be arranged on the inner peripheral side and the yoke 9 may be arranged on the outer peripheral side.

In FIG. 6, on the inner peripheral side, a ring-shaped pole piece 31-1, magnet 7 and pole piece 3 are provided.
1-2 are arranged in this order, and the shaft portion 13d penetrates through the central portion. The yoke 9 has upper and lower springs 15 and 17 fixed (adhered) to the upper and lower surfaces thereof, and at the same time, has a joint portion 29 at the center of the inner circumference and is fixed (adhered) to the central side surface of the magnet 7. .

The vibration unit 10 includes a yoke 9, a magnet 7, a pole piece 31-1 and a pole piece 31-.
2 and the magnetic path and operation similar to those of the embodiment shown in FIGS. 1 and 5 can be realized. In this embodiment,
Since the yoke 9 is arranged around the magnet 7, it is possible to suppress leakage to the surrounding space.

In the embodiment shown in FIGS. 1, 5 and 6, the lower ring 41 supporting the vibration coil 3 and the upper ring 40 supporting the diaphragm 23 are the case 13
The number of parts may be reduced by integrating with the above.

When the demand for impact resistance of the electromagnetic actuator 1 can be relaxed, the shaft portion 13d is formed.
Can be omitted. If the mass of the vibrating body 10 can be reduced, the connecting portion 29 can be omitted in FIGS. 5 and 6. In this case, the central portion 27 of FIG. 5 or
The pole piece 31-2 of FIG. 6 may be adhesively fixed to the bottom surface of the case 13.

[0047]

According to the first aspect of the invention, the vibrating coil is supported by the fixed case, and the vibrating unit is supported by the case via the elastic body, so that stable vibration is obtained. be able to. Further, both a vibration system including a vibration coil for applying a low frequency current and a vibration unit for low frequency vibration and a vibration system including a voice coil for applying a high frequency current and a diaphragm for high frequency vibration are provided. By doing so, each can be designed independently, so that each efficiency can be increased to the maximum value, and sufficient vibration output and good sound can be obtained. In addition, since the voice coil and the vibration coil are arranged by providing a gap on the upper and lower surfaces of the electromagnetic actuator,
The radii of both coils can be freely set, and a sufficient vibration output and a good tone color can be obtained. Further, since the magnet is arranged on the outer peripheral side of the vibrating unit, the output level of vibration and sound can be increased.

According to the second aspect of the present invention, the same effect as that of the first aspect of the present invention can be obtained, and the leakage magnetic flux from the magnet to the surrounding space can be suppressed to be small, and the magnetic noise to the external parts can be suppressed to be small. You can

According to the third aspect of the invention, the same effect as that of the first or second aspect of the invention can be obtained, and the vibration unit can be firmly fixed to the case.

In the invention described in claim 4, the same effect as that of the invention described in any one of claims 1 to 3 is obtained, and by providing the shaft which slidably supports the vibration unit in the vibration direction, The shock resistance is improved, and even if the electromagnetic actuator is placed in any direction, the vibration unit slides smoothly in the axial direction, so that more stable vibration can be obtained.

[Brief description of drawings]

FIG. 1 is a sectional view showing an electromagnetic actuator according to the present invention.

FIG. 2 is an exploded perspective view of the electromagnetic actuator of FIG.

FIG. 3 is a plan view of an elastic body (spring).

FIG. 4 is a cross-sectional view when the electromagnetic actuator of FIG. 1 is mounted in a mobile phone.

FIG. 5 is a sectional view illustrating an electromagnetic actuator of another embodiment.

FIG. 6 is a sectional view illustrating an electromagnetic actuator of another embodiment.

FIG. 7 is a sectional view showing a conventional electromagnetic actuator.

[Explanation of symbols]

1 Electromagnetic actuator 3 Vibration coil 5 voice coils 7,7-1,7-2 Magnet 9 York 10 Vibration unit 13 cases 13d shaft 15 Upper spring (elastic body) 17 Lower spring (elastic body) 23 diaphragm

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Makoto Fujii             No. 3854 Shimotsuruma, Yamato City, Kanagawa Prefecture, Techno             Plaza Yamato Shico Giken Co., Ltd. F term (reference) 5D107 AA05 AA13 AA14 BB08 DD12                       FF10                 5H633 BB08 GG02 GG04 HH03 HH05                       HH09 HH25 JA03

Claims (4)

[Claims] 1. A vibrating coil to which a low-frequency current is applied, a vibrating unit, a case that houses these and supports the vibrating coil, a diaphragm that covers the case, and a diaphragm that faces the vibrating coil. The vibration unit includes a voice coil that is supported and to which a high-frequency current is applied, and an elastic body that supports the vibration unit with respect to the case. The vibration unit is arranged with a radial gap for positioning the vibration coil and the voice coil. A magnet and a yoke integrated with the magnet, the magnet is arranged on the outer peripheral side of the vibrating unit and the yoke is arranged on the inner peripheral side of the vibrating unit. The vibrating unit vibrates when applied, and the diaphragm vibrates when high-frequency current is applied to the voice coil. Yueta. 2. A vibrating coil to which a low-frequency current is applied, a vibrating unit, a case that houses these and supports the vibrating coil, a diaphragm that covers the case, and a diaphragm that faces the vibrating coil. The vibration unit includes a voice coil that is supported and to which a high-frequency current is applied, and an elastic body that supports the vibration unit with respect to the case. The vibration unit is arranged with a radial gap for positioning the vibration coil and the voice coil. The magnet and the yoke integrated with the magnet are arranged. The yoke is arranged on the outer peripheral side of the vibration unit and the magnet is arranged on the inner peripheral side of the vibration unit. The vibrating unit vibrates when applied, and the diaphragm vibrates when high-frequency current is applied to the voice coil. Yueta. 3. The elastic body comprises two springs, each of which has a collar for every 120 ° on the outer circumference and is fixed to a groove provided on the inner circumference of the case to support the vibration unit from above and below. The electromagnetic actuator according to any one of claims 1 to 2, wherein: 4. A shaft for supporting the vibration unit slidably in the vibration direction is provided.
4. The electromagnetic actuator according to any one of 3 to 3.