JP2003080171A - Electromagnetic actuator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electromagnetic actuator that acquires stabilized oscillation. SOLUTION: The electromagnetic actuator is provided with an oscillation unit 10 having penetrated holes, two springs 15, 17 which support the oscillation unit 10, a case 13 which stores the oscillation unit 10 and two springs 15, 17 and supports two springs 15, 17, a diaphragm 23 which covers the one surface of the case 13, a coil 5 on which low frequency and high-frequency currents are applied and a cover 31 which covers the other surface of the case 13 and has a shaft part 31a which penetrates the penetrated holes. The oscillation unit 10 is provided with a magnet, a pole-piece 5 constituting a gap face and a yoke 9 forming a gap in the radius direction which is faced with the pole-piece 5 and is integrated with the magnet 7 and the pole-piece 5. The oscillation unit 10 is oscillated by applying the low frequency current on the coil 5 and the diaphragm 23 is oscillated by applying the high-frequency current on the coil 5.

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 (registered trademark) or the like, 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. 6, in the electromagnetic actuator 100, the magnet 105 is arranged in the groove portion of the yoke 103 in the case 101, the coil 109 is located in the groove portion through the gap with the magnet 105, and is 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, the above-mentioned technique has a problem that when the collar 115 comes into contact with the yoke 103 to regulate the vibration direction, stable friction is impaired due to contact friction.

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

[0005]

According to a first aspect of the present invention, there is provided a vibrating unit having an insertion hole, an elastic body for supporting the vibrating unit, a vibrating unit and an elastic body for accommodating and supporting the elastic body. It has a case, a diaphragm that covers one surface of the case, a coil that is supported by the diaphragm and to which low-frequency and high-frequency currents are applied, and a shaft that covers the other surface of the case and penetrates the insertion hole of the vibration unit. And a vibration unit, and a magnet,
The vibrating unit is provided with a pole piece serving as a gap surface and a yoke that is opposed to the pole piece and forms a radial gap and is integrated with the magnet and the pole piece, by applying a low frequency current to the coil. The diaphragm is characterized by vibrating and applying a high frequency current to the coil.

According to the first aspect of the present invention, by providing the shaft for slidably supporting the vibrating unit in the vibrating direction, even if an external impact is applied to the electromagnetic actuator, for example, an impact at the time of dropping, The position of the vibration unit can be prevented from shifting in the radial direction of the voice coil, and the shock resistance is improved. Further, even if the electromagnetic actuator is placed in any direction, the vibration unit is smoothly slid in the axial direction, so that more stable vibration can be obtained.

According to a second aspect of the present invention, in the first aspect of the present invention, the elastic body is provided with a collar every 120 ° on the circumference of the outer peripheral portion and is fixed to a groove portion provided on the inner peripheral surface of the case. It is characterized in that there are two springs that support the vibration unit.

According to the second aspect of the present invention, since the single case can be structured to support the spring, the vibration unit can be firmly fixed to the case.

According to a third aspect of the present invention, in the first aspect of the invention, the elastic body has a height at the inner peripheral portion with respect to the outer peripheral portion and compresses the height with respect to the case and the cover. It is characterized by two springs that support the vibration unit.

According to the third aspect of the invention, since the outer diameter of the vibration unit can be increased, the vibration force can be increased.

The invention according to claim 4 is the invention according to claims 1 to 3.
In any one of the inventions described above, the shaft is formed by pressing the central portion of the case.

According to the fourth aspect of the present invention, since the shaft is formed by pressing, the strength of the shaft can be made firm and the number of parts can be reduced.

[0013]

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. Is. 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 magnet 7
A vibration unit 10 composed of a magnetic yoke 9 and a pole piece 3, a case 13 for housing these, a lower spring 17 for supporting the lower surface of the vibration unit 10 with respect to the case 13, and a case 13 for the case 13. Vibrating unit 1
0, an upper spring 15 that supports the upper surface of the 0, a diaphragm 23 that is a diaphragm whose periphery is fixed on the upper circumferential end surface of the case 13, and a ring-shaped protrusion 2 of the diaphragm 23.
It is provided with a coil 5 fixed on 3a to which a current is applied, and a cover 31 fixed on the lower circumferential end surface of the case 13 and having a central portion penetrating the vibrating unit 10.
By applying a low-frequency current to the coil 5, the vibrating unit 10 vibrates in the axial direction (vertical direction in FIG. 1) of the shaft 13a that is a part of the cover 31, and by applying a high-frequency current to the coil 5. The diaphragm 23 vibrates and sounds. In the present specification, the terms “upper” and “lower” are used for convenience, but they do not specify the vertical direction.

The case 13 is provided with a terminal portion 13a in one angular direction on the outer peripheral surface, and three groove portions 13f formed from below every 120 ° on the inner peripheral surface and the groove portion 13f are displaced by 60 ° from each other. Three groove portions 13g formed from below for each
It has and. The groove 13f is a deep groove horizontal to the upper surface of the vibrating unit 10, and the groove 13g is the vibrating unit 1.
It is a shallow groove that is horizontal with the bottom surface of 0.

The three flanges 17a of the lower spring 17 are fixed (adhered) to the bottom 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 (adhered) to the bottom surface of the groove portion 13f to support the upper surface of the vibration unit 10, and the lower spring 17 and the outer peripheral lower surface of the yoke 9 and the upper spring 15 and the outer peripheral upper surface of the yoke 9 are adhesively 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 coil 5.

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 flanges 15a and 17a are provided for adhesion and fixing to the case 13. The inner peripheral portions 15b and 17b are provided for adhesion and fixing to the yoke 9.

The diaphragm 23 is formed by molding a thin film of a high molecular compound such as polyethylene into a disc shape, and is fixed to the upper surface of the case 13 by adhesion. 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 coil 5 is bonded is formed into a ring-shaped projection to form a projection 23a. There is. The protrusion 23a is projected toward the gap between the yoke 9 and the pole piece 3, and when the vibration unit 10 vibrates in the vertical direction, the diaphragm 2
It is provided to avoid collision with the No. 3 vehicle. In the small electromagnetic actuator 1, the intrinsic basic (minimum) frequency of the diaphragm 23 is a high frequency around 1 kHz, so the current applied to the coil 5 to vibrate the diaphragm 23 and generate a sound is called a high frequency current. I'm out.

The cover 31 is formed by molding a metal plate of aluminum or the like into a disc shape, and is fixed by adhesion to the circumferential surface of the lower surface of the case 13. The central portion is formed with a shaft portion 31a by press-molding so as to project to the inside of the case 13, and is provided with a plurality of holes 31b that serve as escape ports for internal air.

A hole through which the shaft portion 31a is inserted is provided in the central portion of the pole piece 3, the magnet 7 and the yoke 9, and they are arranged in this order and bonded to form the vibration unit 10. With this structure, the vibration unit 1
0 is the shaft portion 3 which is inserted into the insertion hole 10a in the central portion.
1a allows the shaft portion 31a to slide in the axial direction.

By providing the shaft portion 31a for slidably supporting the vibration unit 10, the electromagnetic actuator 1 is dropped when the electromagnetic actuator 1 is dropped.
Even when a shock is applied from the outside, the position of the vibration unit 10 can be prevented from shifting toward the outer peripheral direction (to the left and right in FIG. 1), and the shock resistance is improved. At the same time, the vibration direction of the vibration unit 10 is restricted to the axial direction.

The lead wire of the coil 5 is the diaphragm 23.
It is connected to the terminal portion 13a through the joint surface with the case 13 while being adhered to the lower surface of the. In the terminal portion 13a,
High and low frequency currents are supplied from within the cell phone.

Next, the operation of this embodiment will be described based on the above-mentioned configuration. To assemble the electromagnetic actuator 1, the yoke 9, the magnet 7 and the pole piece 3 are fixed (adhered) to assemble the vibration unit 10, and subsequently, the upper spring 15 is attached to the upper surface of the vibration unit 10.
The lower spring 17 is fixed (bonded) to the lower surface.

Then, the unit in which the vibration unit 10 and the upper and lower springs 15 and 17 are integrally fixed is fixed (bonded) to the bottoms of the groove portions 13g and 13f of the case 13. Next, the cover 31 is bonded to the lower surface circumferential portion of the case 13 while inserting the shaft portion 31a into the insertion hole 10a. The coil 5 is previously attached to the lower surface of the diaphragm 23.
, And at the same time, the coil lead wire is the diaphragm 23.
Provide a lead wire to the outside while adhering to the bottom surface of the.
Finally, the diaphragm 23 having the coil 5 attached thereto is adhered to the circumferential portion of the upper surface of the case 13, and at the same time, the lead wire is connected to the terminal portion 13a.

In this electromagnetic type actuator 1, a low frequency current (for example, a single frequency of 100 to 150 Hz as a sensory frequency) is applied to the coil 5 from a circuit in the mobile phone.
Is applied, the vibration unit 10 vibrates in the axial direction of the shaft portion 13d due to the action of the low frequency current and the magnetic field of the gap portion. 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.

When a high frequency current (a wide band frequency of 900 to 8000 Hz as an audible frequency) is applied to the coil 5, the diaphragm 23 vibrates in the high frequency band due to the action of the high frequency current and the magnetic field of the gap. Cause Since the diaphragm 23 is a diaphragm formed of a thin film material such as polyethylene in a cone shape, it faithfully emits acoustic waves with respect to the driving force in the high frequency band via the coil 5. When the diaphragm 23 vibrates, a high frequency sound transmits information such as an incoming call signal to the wearer through the acoustic radiation hole of the housing of the mobile phone fixing the case 13.

That is, when a low frequency current is applied to the coil 5 from the mobile phone, a low frequency vibration is generated, when a high frequency current is applied, a high frequency sound is generated, and when both are applied, the low frequency vibration and the high frequency sound are generated. Both occur.

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. However, in the present embodiment, the shaft portion 13d is inserted in the center of the vibrating unit 10, so that the vibrating direction is set 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, since the shaft portion 31a is formed by pressing a part of the metal cover 31, the strength of the shaft can be made strong and at the same time, the structure is low in cost and the number of parts is reduced. can do.

Next, another embodiment will be described. In the description, the same parts as those described above are designated by the same reference numerals, and the description thereof will be omitted.

FIG. 4 is a sectional view showing an electromagnetic actuator according to the second embodiment, and FIG. 5 is a perspective view of a spring used in the second embodiment. In the second embodiment, as shown in FIG. 4, the upper spring 15 is arranged between the upper circumferential portion of the vibration unit 10 and the protruding portion 13b of the upper portion of the case 13, and the lower circumferential portion of the vibration unit 10 and the cover are covered. The lower spring 17 is arranged between 31.

As shown in FIG. 5, the upper and lower springs 1
5, 17 are outer peripheral portions 15a, 17a and inner peripheral portions 15b, 1
In the natural state, the height h is maintained between the outer peripheral portions 15a and 17a and the inner peripheral portions 15b and 17b. The outer peripheral portion 15a of the upper spring 15 is adhered to the protrusion 13b, the inner peripheral portion 15b is adhered to the upper surface of the yoke 9, and the outer peripheral portion 17a of the lower spring 17 is adhered to the case 31.
7b is attached to the lower surface of the yoke 9 to be assembled. By this assembling process, the upper and lower springs 15 and 17 are compressed to approximately ½ of the height h shown in FIG. 5 and intervene in the arrangement shown in FIG. The resonance frequency of the vibration system, which is composed of the mass of the vibration unit 10 and the spring coefficient of the main spring, is matched with the frequency of the low-frequency current.

In the present embodiment, the shaft 11 which is separate from the case 31 is fixed (adhered) to the central portion of the case 31 and inserted into the insertion hole 10a of the vibration unit 10. As a result, the vibration unit 10 can be slid in the axial direction of the shaft 11. By providing the shaft 11, the shock resistance is improved and the vibration direction of the vibration unit 10 is regulated in the axial direction.

In the second embodiment, since the upper and lower springs 15 and 17 support the vibrating unit 10 in a compressed state, the outer diameter of the vibrating unit can be increased and the vibrating force can be increased. .

[0036]

According to the first aspect of the present invention, by providing the shaft for slidably supporting the vibrating unit in the vibrating direction, the shock resistance is improved and the electromagnetic actuator is placed in any direction. However, since the vibration unit is slid in the axial direction smoothly, more stable vibration can be obtained.

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

According to the invention described in claim 3, the same effect as the invention described in claim 1 can be obtained, and the vibration force can be increased.

According to the invention described in claim 4, the same effect as that of the invention described in any one of claims 1 to 3 can be obtained, the strength of the shaft can be made strong, and the number of parts can be reduced. You can

[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 sectional view showing an electromagnetic actuator of another embodiment.

FIG. 5 is a perspective view of an elastic body (spring) of another embodiment.

FIG. 6 is a cross-sectional view showing a conventional electromagnetic actuator.

[Explanation of symbols] 1 Electromagnetic actuator 3 pole pieces 5 coils 7 magnet 9 York 10 Vibration unit 10a insertion hole 11 shaft 13 cases 15 Upper spring (elastic body) 17 Lower spring (elastic body) 23 diaphragm 31 cover 31a shaft part

   ─────────────────────────────────────────────────── ─── 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 AA14 BB08 CC09 DD12                       DE02 EE01 FF10                 5H607 AA17 BB08 BB21 CC03 DD09                       DD16 EE57                 5H633 BB08 GG02 GG06 GG09 HH03                       HH05 HH16 JA03 JA04

Claims (4)

[Claims] 1. A vibrating unit having an insertion hole, an elastic body supporting the vibrating unit, a case accommodating the vibrating unit and the elastic body and supporting the elastic body, and a diaphragm covering one surface of the case. The vibration unit includes a coil supported by the diaphragm and to which low-frequency and high-frequency currents are applied, and a cover having a shaft that covers the other surface of the case and penetrates the insertion hole of the vibration unit. The vibration unit vibrates by applying a low-frequency current to the coil, which has a pole piece that serves as a surface and a yoke that forms a gap in the radial direction facing the pole piece and is integrated with the magnet and pole piece. An electromagnetic actuator characterized in that the diaphragm vibrates when a high-frequency current is applied to the coil. 2. The elastic body is provided with a collar for every 120 ° on the outer circumference, and is fixed to a groove provided on the inner circumference of the case,
The electromagnetic actuator according to claim 1, wherein the spring is two springs that support the vibration unit. 3. The elastic body comprises two springs having a height at an inner peripheral portion with respect to an outer peripheral portion and supporting the vibration unit by compressing the height with respect to a case and a cover. The electromagnetic actuator according to claim 1. 4. The electromagnetic actuator according to claim 1, wherein the shaft is formed by pressing the central portion of the case.