JP2000278928A - Oscillatory actuator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent deterioration of performance by securing a supporting hand formed on the outer circumference of a damper having a spiral part into a groove made in the outer circumferential surface of a yoke in a magnetic circuit and supporting the magnetic circuit flexibly at two points in the center and on the outer circumferential surface thereby limiting inclination of the axis of the magnetic circuit during oscillation. SOLUTION: A damper 7 is provided with a plurality of spiral parts 30 for supporting, at the central part thereof, the center on the yoke 1 side of a magnetic circuit 20 flexibly. Three supporting hands 8 for reducing abnormal stress to the damper 7 are formed at the outer circumferential part of the damper 7. End part 22 of the supporting hand 8 is secured into the groove 21 of a yoke 1. The damper 7 is secured integrally by means of a hole 17 made in the outer fringe part and the protrusion 23 on a supporting frame 9. When a drive current is applied to a coil 5, the magnetic circuit 20 supported flexibly by the damper 7 and the supporting frame 9 oscillates but since it is supported on the outer circumferential surface of the yoke 1 by means of the damper 7, the central shaft 4 and the supporting hands 8, inclination of the axis of the magnetic circuit 20 is limited during oscillation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibration actuator which is mounted on a mobile communication device such as a portable telephone and uses a magnetic circuit for generating a ringing sound, a voice and vibration.

[0002]

2. Description of the Related Art Conventionally, this type of vibration actuator has
For example, it is described in Japanese Patent Application No. 8-324997 (vibration actuator for pager). This vibration actuator includes a magnetic circuit 20 composed of a permanent magnet 2, a yoke 1, and a plate 3, as shown in FIG.

Further, the magnetic circuit 20 is vertically movable by a resin damper 7 and a supporting rubber 13 which is a flexible structure attached to a claw-like projection 12 provided on a support base 11. It is supported.

When a drive current is applied to the coil 5, the magnetic circuit 2
Numeral 0 moves up and down in the axial direction, and transmits vibration to the outside via the damper outer peripheral portion 15 and the support base 11.

The center shaft 4 is a shaft connecting the magnetic circuit 20 to the damper 7, and the elastic member 16 is an elastic member for preventing the yoke 1 from directly colliding with the support 11.

[0006]

However, in a conventional vibration actuator having such a structure, the center shaft 4 connected to the magnetic circuit 20 is supported by the damper 7, but when the shock is abnormally applied. For example, the magnetic circuit 20
May be tilted. At this time, the coil 5 and the magnetic circuit 2
0 may come in contact with it and generate an abnormal sound, or abnormal stress may be applied to the damper 7.

Therefore, conventionally, the inclination of the axis of the magnetic circuit 20 is suppressed by the supporting rubber 13 and the magnetic circuit 20 is lifted by the drive offset voltage.
Although contact between the coil and the magnetic circuit is suppressed, there is a demand for a higher impact resistance and higher reliability so that the coil can be used in a harsh environment.

Accordingly, an object of the present invention is to suppress the inclination of the axis of the magnetic circuit at the time of vibration such as an abnormal shock, and to make contact between the coil and the magnetic circuit or to apply abnormal stress to the damper. An object of the present invention is to provide a vibration actuator having higher shock resistance and higher reliability without causing performance degradation.

[0009]

According to the present invention, a support arm formed on the outer periphery of a damper having a spiral portion is fixed to a groove provided on the outer peripheral surface of a yoke of a magnetic circuit. The outer peripheral surface of the circuit and the center axis of the magnetic circuit are positioned by the central axis, and the magnetic circuit is flexibly supported at two points to suppress the tilt of the magnetic circuit axis during vibration. Thus, a vibration actuator that does not come into contact with or does not cause performance deterioration due to abnormal stress applied to the damper can be obtained.

That is, according to the present invention, a magnetic circuit and a damper composed of a yoke, a permanent magnet, and a plate are positioned coaxially by a central axis, and a drive current is passed through a coil disposed in a gap of the magnetic circuit. A vibration actuator that causes the magnetic circuit to vibrate, wherein the damper includes:
The magnetic circuit has a spiral portion at the center thereof, and a plurality of supports formed on the outer periphery thereof are fixed to grooves provided on the outer periphery of the yoke, so that the magnetic circuit is formed at the center and the outer periphery. This is a vibration actuator that flexibly supports two places.

Further, the present invention is the above-mentioned vibration actuator, wherein the damper is arranged on a yoke side of the magnetic circuit.

Further, according to the present invention, the damper is preferably made of SUS30.
4. The vibration actuator described above, which is formed of at least one kind of metal spring material of SUS301, nickel silver, phosphor bronze, and Be-Cu alloy.

Further, the present invention is the above-described vibration actuator, wherein a hole is provided in an outer peripheral edge of the damper, and the damper is fixed to a protrusion of the support frame by a heat caulking process.

Further, the present invention is the above-mentioned vibration actuator, wherein a plurality of supporting hands are provided between a center portion and an outer peripheral edge of the damper, and are fixed to grooves on the outer peripheral surface of the yoke of the magnetic circuit.

Further, the present invention is the above-described vibration actuator, wherein the magnetic circuit and the damper are integrated with a projection provided on the center shaft by a pressure bonding process.

Further, the present invention is the above-mentioned vibration actuator, wherein the coil is inserted into a concave portion provided in the support plate and fixed by bonding.

[0017]

Embodiments of the present invention will be described below in detail.

FIG. 1 is an explanatory view of a vibration actuator according to an embodiment of the present invention. FIG. 1 (a) is a plan view, and FIG. 1 (b) is a sectional view taken along the line AA of FIG. 1 (a). is there.

In FIG. 1, a magnetic circuit 2 is arranged such that a disk-shaped permanent magnet 2 is sandwiched between a yoke 1 and a plate 3.
0 is formed. The central shaft 4 has a shape like a bolt, is fitted in the concave portion 24 of the plate 3, penetrates the central hole of the magnetic circuit 20, and further fits into the central holes of the damper 7 and the spacer 10. In other words, the magnetic circuit 20 and the damper 7 and the support frame 9 for fixing them are coaxially positioned by the center shaft 4.

A plurality of spiral portions 30 are formed in the damper 7 so that the center portion flexibly supports the center of the magnetic circuit 20 on the yoke 1 side. Further, on the outer peripheral portion of the damper 7, three support hands 8 for reducing abnormal stress on the damper 7 are formed, and the end 22 of the support hand 8 is fixed to the groove 21 of the yoke 1. .

The damper 7 is fixed and integrated with a hole 17 provided on the outer edge thereof and a projection 23 of the support frame 9. The support plate 6 is formed with a groove in which the coil 5 is coaxially positioned and inserted, and is fixed to the support frame 9.

Here, when a drive current is applied to the coil 5, the magnetic circuit 20 flexibly supported by the damper 7 and the support frame 9 vibrates. At this time, since the magnetic circuit 20 is supported by the damper 7 at two places on the outer peripheral surface of the yoke 1 by the center shaft 4 and the three supporting hands 8, the magnetic circuit
The inclination of the 0 axis can be suppressed.

Therefore, the coil 5 and the magnetic circuit 20 do not come into contact with each other, or abnormal stress is applied to the damper 7, thereby preventing performance degradation. Further, by providing a plurality of supporting hands between the center portion and the outer peripheral edge portion of the damper, the impact resistance can be further improved.

[0024]

As described above, according to the present invention, the inclination of the axis of the magnetic circuit at the time of vibration due to abnormal shock or the like is suppressed, and the coil and the magnetic circuit come into contact with each other, or abnormal stress is applied to the damper to degrade the performance. Thus, it is possible to provide a vibration actuator having high shock resistance and high reliability without causing any problem.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of a vibration actuator according to an embodiment of the present invention. FIG. 1A is a plan view, and FIG.
(A) sectional drawing of AA.

FIG. 2 is a sectional view of a conventional vibration actuator.

[Explanation of symbols]

 Reference Signs List 1 yoke 2 permanent magnet 3 plate 4 center axis 5 coil 6 support plate 7 damper 8 support hand 9 support frame 10 spacer 11 support base 12 claw-like projection 13 support rubber 14 bobbin 15 damper outer peripheral portion 16 elastic material 17 hole 20 magnetic circuit 21 Groove 22 End 23 Projection 24 Recess 30 Spiral

Claims (7)

[Claims] A magnetic circuit and a damper comprising a yoke, a permanent magnet, and a plate are coaxially positioned by a central axis, and a drive current is applied to a coil disposed in a gap of the magnetic circuit, so that a magnetic circuit is formed on the magnetic circuit. A vibration actuator that causes vibration, wherein the damper has a spiral portion at a central portion thereof, and fixes a plurality of support hands formed on an outer peripheral portion thereof to grooves provided on an outer peripheral surface of the yoke. Thus, the vibration circuit is characterized in that the magnetic circuit is flexibly supported at two locations, a central portion and an outer peripheral surface. 2. The vibration actuator according to claim 1, wherein the damper is disposed on a yoke side of the magnetic circuit. 3. The SUS304, SUS3
3. The vibration actuator according to claim 1, wherein the vibration actuator is made of at least one kind of metal spring material among metal spring materials of 01, nickel silver, phosphor bronze, and Be-Cu alloy. 4. A hole is provided in an outer peripheral edge of the damper,
The vibration actuator according to any one of claims 1 to 3, wherein the vibration actuator is fixed to the protrusion of the support frame by a heat caulking process. 5. The magnetic circuit according to claim 1, wherein a plurality of supports are provided between a central portion and an outer peripheral edge of the damper, and the magnetic circuit is fixed to a groove on an outer peripheral surface of the yoke of the magnetic circuit. The vibration actuator according to any one of claims 1 to 4, wherein the vibration actuator is flexibly supported at two places. 6. The vibration actuator according to claim 1, wherein the magnetic circuit and the damper are integrated with a protrusion provided on the central axis by a pressure bonding process. 7. The vibration actuator according to claim 1, wherein the coil is fixed in a recess provided in a support plate by being inserted and bonded.