Patent Description:
Conventionally, a vibration actuator has been known as a vibration generation source for notifying incoming calls and/or the like of mobile information terminals such as mobile phones to users or as a vibration generation source for transmitting a sense of touch when operating touch screens and a sense of reality in games played on amusement machines such as controllers of game machines to fingers, hands, feet, and the like (see Patent Literatures (hereinafter, each referred to as "PTL") <NUM> to <NUM>, for example).

The vibration actuator disclosed in PTL <NUM> is formed flat to reduce the size. The vibration actuator of PTL <NUM> has a flat-plate shape in which a pivotally supported movable part is supported freely slidably by a shaft.

The vibration actuator disclosed in PTL <NUM> includes: a stator having a casing and a coil; and a movable element having a magnet and a weight disposed inside the casing, in which the movable element freely slidable with respect to a shaft linearly vibrates in a vibration direction with respect to the stator by cooperation work of the coil and the magnet. The coil is wound on an outer side of a movable part including the magnet.

Further, PTL <NUM> discloses an actuator of the VCM (Voice Coil Motor) principle, including opposite flat coils and flat magnets disposed on the flat coils.

The movable element is provided freely slidable to the shaft in all of those vibration actuators, and elastically supported by the springs to be capable of vibrating in the vibration direction. In the vibration actuator using VCM as the driving principle, a magnetic attraction force does not work under a normal state due to its magnetic circuit configuration. Therefore, mainly a metal spring is employed for elastically holding the movable part.

PTL4 describes that a vibration generating unit includes a U-shaped leaf spring, an electromagnetic coil, a weight fixed to the tip of the U-shaped leaf spring, and a permanent magnet fixed to the lower part of the electromagnetic coil.

PTL5 describes that a vibration generator includes a U-shaped leaf spring, a permanent magnet, an electromagnetic coil, a weight, and the like. The weight and the permanent magnet are suspended and fixed to the vibrating end of the leaf spring, and the electromagnetic coil (air core coil) is disposed in the lower part facing the permanent magnet.

PTL6 describes a vibration generator including a housing, a vibrating member, a heavy body, and a piezoelectric element.

Specifically, the heavy body is provided with a damper for preventing a collision with the housing.

PTL7 describes that a spring oscillator includes a coil mounted on a substrate through which a coil current flows, a leaf spring having one end provided on the substrate, a magnet provided on the leaf spring and a weight provided so that the leaf spring vibrates properly.

PTL8 describes that a vibration generator includes a cylindrical coil provided at one end of the base, a spacer provided at the other end of the base, a metal leaf spring configured to include a circular permanent magnet at one end of the base and fixed to a spacer at the other end of the base. The permanent magnet is configured to be inserted into the coil so that it is possible for the permanent magnet to be freely taken in and out of the coil.

PTL9 describes that that a vibration generator includes a U-shaped leaf spring, a permanent magnet, an electromagnetic coil, a weight, and the like. The weight and the electromagnetic coil are suspended and fixed to the vibrating end of the leaf spring, and the permanent magnet is disposed in the lower part facing the electromagnetic coil.

Recently, those vibration actuators are considered to be incorporated as an incoming notification function device or the like on a mobile terminal or a wearable terminal that are apparatuses in a form used by being worn on the bodies of users such as wrist watches, rings, or the like.

In order to generate vibration enough for the user to feel a bodily sensation with the incoming notification function device in the mobile terminal, the wearable terminal, or the like, a device with large vibrations is desired.

The conventional vibration actuators disclosed in PTLs <NUM> to <NUM> are in a configuration capable of easily increasing vibrations by being driven in a longitudinal direction inside a flat cuboid-shape casing.

When those actuators are incorporated in a wearable terminal and disposed on a mounting face such as a body surface or the like, the vibration direction becomes parallel to the mounting face. Therefore, with the vibration actuator in which the movable body drives in a parallel direction, it is hard to feel bodily sensation.

An object of the present invention is to provide a vibration actuator, a wearable terminal, and an incoming notification function device capable of reducing the size and capable of acquiring vibrations felt by the body in a fine manner.

One aspect of a vibration actuator of the present invention includes:.

One aspect of a wearable terminal of the present invention includes the vibration actuator of the above configuration mounted thereon. Further, an incoming notification function device of the present invention includes the vibration actuator of the above configuration mounted thereon.

The present invention achieves the vibration actuator capable of reducing the size, excellent in assemblability and durability, and capable of vibrating favorably.

Embodiments of the present invention will be described in detail hereinafter with reference to the accompanying drawings.

<FIG> is an external view illustrating a configuration of a vibration actuator according to Embodiment <NUM> of the present invention, <FIG> is a perspective view illustrating a state where a cover is removed from the vibration actuator, and <FIG> is an exploded perspective view of the vibration actuator. Further, <FIG> is a longitudinal sectional view of the configuration of main components of the vibration actuator, <FIG> is a diagram illustrating the configuration of a magnetic circuit of the vibration actuator, and <FIG> is a longitudinal sectional view illustrating actions of a movable body in the vibration actuator.

Vibration actuator <NUM> illustrated in <FIG> includes casing <NUM> of a cuboid external shape formed with base plate <NUM> and cover <NUM>. The shape of casing <NUM> in vibration actuator <NUM> of the embodiment is formed such that, among a height, a width, and a depth, the depth becomes the longest and the height becomes the shortest in any dimensions. Note that casing <NUM> may not be in a cuboid shape but may be in any other shapes such as a cubic shape as long as it is a shape capable of housing movable body <NUM> movably.

Vibration actuator <NUM> includes: fixing body <NUM> including casing <NUM>; movable body <NUM> that vibrates (one end side reciprocally oscillates by having the other end side as a fulcrum) with respect to fixing body <NUM> inside casing <NUM>; and plate spring part <NUM> as a plate-like elastic body.

In vibration actuator <NUM>, a first end portion of movable body <NUM> that is disposed opposite to base plate <NUM> and has a second end portion supported by plate spring part <NUM> works as a free end and reciprocally vibrates in a height direction with respect to base plate <NUM>.

Specifically, fixing body <NUM> includes base plate <NUM>, cover <NUM>, first magnet holder <NUM>, second magnet holder <NUM>, first magnet <NUM>, and second magnet <NUM>, and movable body <NUM> includes coil <NUM>, main body part <NUM> (coil holder <NUM> and weight <NUM>), and contact parts <NUM>.

Base plate <NUM> is formed in a rectangular shape, has movable body <NUM> disposed on its surface side by being isolated therefrom, and forms casing <NUM> together with cover <NUM>.

Base plate <NUM> is formed with a plate material exhibiting conductivity together with cover <NUM> to be described later, and functions as an electromagnetic shield.

First magnet <NUM> is fixed on base plate <NUM> via first magnet holder <NUM>.

First magnet holder <NUM> positions and fixes first magnet <NUM> on base plate <NUM>. First magnet holder <NUM> in the embodiment is formed in a flat rectangular frame shape surrounding first magnet <NUM>, and first magnet <NUM> is disposed inside thereof. First magnet holder <NUM> in the embodiment is disposed such that first magnet <NUM> comes to be positioned at base-end side portion 30a of movable body <NUM>.

While first magnet holder <NUM> may be formed with any materials such as metal and resin, it is preferable to be nonmagnetic so as not to give an influence on a flow of magnetic flux such as distorting distribution of the magnetic flux emitted from magnetic poles of the magnets (especially first magnet <NUM>). First magnet holder <NUM> of the embodiment is formed with nonmagnetic stainless together with second magnet holder <NUM>. Because first magnet holder <NUM> is nonmagnetic, it is possible at the time of assembling vibration actuator <NUM> to preferably dispose first magnet holder <NUM> at a prescribed position without being attracted to first magnet <NUM> and second magnet <NUM> so that vibration actuator <NUM> can be assembled easily.

First magnet <NUM> is fixed such that its magnetization direction becomes a perpendicular direction with respect to base plate <NUM>. In the embodiment, first magnet <NUM> is formed in a rectangular shape with its S-pole being disposed on base plate <NUM> side and N-pole being disposed on a top face side.

First magnet <NUM> is inserted into coil <NUM> of movable body <NUM> along with second magnet <NUM>.

Cover <NUM> is attached to cover base plate <NUM>, and houses movable body <NUM> inside casing <NUM> that is formed together with base plate <NUM>. Casing <NUM> houses movable body <NUM> to be freely movable.

Movable body <NUM> is disposed on the inner side of cover <NUM> to be freely movable. In the embodiment, top plate <NUM> of cover <NUM> is disposed opposite to base plate <NUM> with movable body <NUM> interposed therebetween.

Second magnet <NUM> located on top plate <NUM> by second magnet holder <NUM> is fixed to cover <NUM>. Note that a part of top plate <NUM> where second magnet <NUM> is fixed and a part of base plate <NUM> where first magnet <NUM> is fixed also function as yokes.

Second magnet holder <NUM> is formed in the same manner as that of first magnet holder <NUM>. In this embodiment, second magnet holder <NUM> is formed in a flat rectangular frame shape surrounding second magnet <NUM>, and second magnet <NUM> is disposed on an inner side thereof. Second magnet holder <NUM> is disposed opposite to first magnet holder <NUM>. Second magnet holder <NUM> locates second magnet <NUM> formed in the same manner as that of first magnet <NUM> at a position opposing to first magnet <NUM>.

As illustrated in <FIG>, right above first magnet <NUM>, second magnet <NUM> is disposed with the magnetization direction set different from the magnetization direction of first magnet <NUM>.

That is, second magnet <NUM> and first magnet <NUM> are disposed opposite to each other with the same magnetic polarity.

As illustrated in <FIG> and <FIG>, a lower face of second magnet <NUM> in the embodiment is an N-pole face, and second magnet <NUM> is disposed with a space provided between the lower face of second magnet <NUM> and a top face of the N-pole of first magnet <NUM>. Second magnet <NUM> is inserted into coil <NUM> of movable body <NUM> while being isolated from the inner peripheral face of coil <NUM>.

In movable body <NUM>, coil <NUM> and main body part <NUM> are joined side by side in a direction (front-and-back direction in <FIG>) orthogonal to the magnetization direction of first magnet <NUM> and second magnet <NUM>.

Coil <NUM> together with first magnet <NUM> and second magnet <NUM> generates a magnetic force to electromagnetically drive movable body <NUM>. Coil <NUM> is disposed on an outer periphery side of first magnet <NUM> and second magnet <NUM> with a prescribed space provided therebetween surrounding the top face of first magnet <NUM> and the lower face of second magnet <NUM> opposing to each other.

Coil <NUM> has a shape fitting the external shapes of first magnet <NUM> and second magnet <NUM>. Coil <NUM> in the embodiment is formed in a square frame shape to fit the external shape of first magnet <NUM> and second magnet <NUM>, and disposed to be wound around the periphery of first magnet <NUM> and second magnet <NUM> in the direction orthogonal to the magnetization direction of first magnet <NUM> and second magnet <NUM>.

That is, it is preferable for a winding axis of coil <NUM> to be parallel to the magnetization direction of first magnet <NUM> and second magnet <NUM> of fixing body <NUM>. The winding axis of coil <NUM> in the embodiment under an undriven state overlaps with a center axis of first magnet <NUM> and second magnet <NUM>, and opposes to first magnet <NUM> and second magnet <NUM> in a width direction and a depth direction with a prescribed space provided therebetween. The prescribed space herein is a space capable of allowing coil <NUM> to move in the thickness direction with respect to first magnet <NUM> and second magnet <NUM> and, more specifically, is a space capable of allowing coil <NUM> to oscillate in the thickness direction in accordance with oscillation of movable body <NUM>.

In coil <NUM>, a power supply part (not illustrated) is connected to coil wire 40a extruded out to the base end side from a coil wound portion. The power supply part is connected to an external power, and supplies electric power to coil <NUM> to generate a magnetic force.

Coil <NUM> is attached to main body part <NUM> of movable body <NUM> via coil holder <NUM>.

Main body part <NUM> includes a first end portion to which plate spring part <NUM> as an elastic body is attached and a second end portion as a free end. Main body part <NUM> in the embodiment is configured with coil holder <NUM> and weight <NUM>.

Coil holder <NUM> fixes movable body fixing part <NUM> as the second end portion of plate spring part <NUM> to movable body <NUM>, and holds coil <NUM>.

Coil holder <NUM> in the embodiment is formed in a rectangular frame shape to have coil <NUM> disposed on an inner side of the frame part, and fixes coil <NUM> at an outer periphery face thereof. Coil holder <NUM> in the embodiment is formed by processing a sheet metal made with stainless material. Note that coil holder <NUM> may be formed with a material of high specific gravity (specific gravity of about <NUM> to <NUM>) such as tungsten that is of high specific gravity as long as it is capable of being formed into the above shape and dimensions. In such case, the mass of the movable body can be increased because of the high specific gravity.

Plate spring part <NUM> is fixed at one side face of coil holder <NUM>, and weight <NUM> is adjacently fixed at the other side face on the opposite side of plate spring part <NUM>. Movable body <NUM> carries coil <NUM> on one end side of movable body <NUM> while carrying weight <NUM> on the other end side.

Weight <NUM> is a weight provided to movable body <NUM> supported by plate spring part <NUM> as a plate-like elastic body to increase output of vibrations of movable body <NUM>. Weight <NUM> in the embodiment is attached to extend in a direction orthogonal to the axis of the coil from coil holder <NUM> and to an inverse side of the direction where plate spring part <NUM> extends on fixing body <NUM> side.

Weight <NUM> is formed with a material of high specific gravity such as tungsten that is of higher specific gravity than a material such as SECC, for example. Thereby, when it is desired to increase the mass of movable body <NUM> whose external shape dimensions are set in design and the like, weight <NUM> may be formed with a high specific gravity material with the specific gravity of about <NUM> to <NUM> so that the mass for the specific gravity can be included in the mass of the movable body. As a result, the output of vibrations of movable body <NUM> can be increased.

Weight <NUM> is in a plate-like cuboid shape and, in the embodiment, formed in the same thickness as the height of coil holder <NUM>. Thereby, upper end faces of coil holder <NUM> and weight <NUM> are flush with each other, and lower end faces thereof are flush with each other.

Contact parts <NUM> are attached at tip ends of weight <NUM> in the oscillation directions, that is, in approaching and leaving directions with respect to base plate <NUM> herein. Contact parts <NUM> oppose to each of top plate <NUM> and base plate <NUM> in the vibration directions.

Contact parts <NUM> are dampers (cushioning material), and abut against base plate <NUM> and top plate <NUM> of cover <NUM> when movable body <NUM> oscillates. Contact parts <NUM> herein are formed with a soft material such as an elastomer, rubber, resin, and a porous elastic body such as a sponge. Thereby, when coming to contact with base plate <NUM> or top plate <NUM> at the time of driving movable body <NUM>, it is possible to ease the impact at the time of contact and reduce generation of a contact sound and a vibration noise when the impact at the time of contact is transmitted to casing <NUM>.

Plate spring part <NUM> has its one end fixed to fixing body <NUM> and the other end fixed to movable body <NUM>, thereby forming a cantilever structure to support movable body <NUM> to be reciprocally oscillatable in the vibration direction. Plate spring part <NUM> supports movable body <NUM> to be able to oscillate in a direction crossing with (herein, orthogonal to) the longitudinal direction of casing <NUM>.

Plate spring part <NUM> in the embodiment is formed with a plate spring. Plate spring part <NUM> is formed by bending a long plate, and includes fixing body fixing part <NUM> to be fixed to fixing body <NUM>, elastically deformable arm part <NUM>, and movable body fixing part <NUM> to be fixed to movable body <NUM>.

Fixing body fixing part <NUM> is fixed on the first end portion side of the surface of base plate <NUM> by bonding, welding, or the like. Arm part <NUM> includes rising plate part <NUM> extruded out from fixing body fixing part <NUM> to rise upward, and bending plate part <NUM> bent from rising plate part <NUM> along base plate <NUM>. In bending plate part <NUM>, movable body fixing part <NUM> is formed to suspend from a tip end of bending plate part <NUM> toward base plate <NUM> side. Movable body fixing part <NUM> is fixed in surface-contact with one side face of coil holder <NUM> by bonding, welding, or the like.

Through plate spring part <NUM>, movable body <NUM> is disposed inside casing <NUM> at an intermediate position between base plate <NUM> and top plate <NUM> of cover <NUM> by being cantilevered substantially in parallel to each of base plate <NUM> and top plate <NUM>.

An external power is connected to coil <NUM> via a power supply part (not illustrated) that supplies electric power to coil <NUM>.

In vibration actuator <NUM>, movable body <NUM> is disposed to be oscillatable by having its one end side elastically supported by plate spring part <NUM> between base plate <NUM> of fixing body <NUM> and top plate <NUM> of cover <NUM>. In addition, first magnet <NUM> and second magnet <NUM> are disposed in coil <NUM> of movable body <NUM>, and fixed to base plate <NUM> and top plate <NUM> by having magnetic pole faces of the same polarity (N-pole faces in <FIG>) opposed to each other.

Through supplying electric power from the power supply part to energize coil <NUM>, movable body <NUM> is reciprocally vibrated in the height direction (lateral direction), that is, in approaching and leaving directions with respect to base plate <NUM> and top plate <NUM>. Thereby, the second end portion of movable body <NUM> is oscillated.

For example, on vibration actuator <NUM>, generated is flow B of magnetic flux illustrated in <FIG>. When power is supplied to coil <NUM> in vibration actuator <NUM>, an electric current flows in coil <NUM> that is disposed to be orthogonal to the magnetic flux from first magnet <NUM> and second magnet <NUM>. By the Lorentz force generated thereby, thrust F is generated in coil <NUM> based on Fleming's left hand rule so that movable body <NUM> is driven in F direction. Thereby, movable body <NUM> is supported by plate spring part <NUM> on the first end portion side, so that, as illustrated in <FIG>, the second end portion of movable body <NUM>, that is, weight <NUM> side, oscillates and moves in the F direction and contacts (specifically collides) with top plate <NUM> of cover <NUM> via contact part <NUM>.

Further, when an electric current changed to an inverse direction is supplied to coil <NUM> (when the flowing direction of the electric current in <FIG> is inversed), coil <NUM> returns to a reference position at the time of change, -F force is generated in coil <NUM> by the Lorenz force, and movable body <NUM> is driven in -F direction that is exactly opposite from F direction. Movable body <NUM> is supported by plate spring part <NUM> on the first end portion side, so that the second end portion of movable body <NUM>, that is, weight <NUM> side oscillates and moves in -F direction and collides with base plate <NUM> via contact part <NUM> (a state of movable body <NUM> illustrated with a broken line).

In vibration actuator <NUM>, coil <NUM> is energized by an alternating current wave input to coil <NUM> from the power supply part, and the Lorentz force is effectively generated to first magnet <NUM> on fixing body <NUM> side and second magnet <NUM>. Thereby, coil <NUM> of movable body <NUM> acquires the thrust in F direction and -F direction with respect to the position to be the driving reference position (herein, the position at which the center position of coil <NUM> in the height direction comes on substantially the same horizontal plane with the intermediate position between the opposing magnetic pole faces of the same polarity of first magnet <NUM> and second magnet <NUM>).

Thereby, coil <NUM> of movable body <NUM> reciprocally vibrates in F direction and -F direction along the height direction. That is, movable body <NUM> reciprocally vibrates with respect to fixing body <NUM> in an arc form in a direction orthogonal to base plate <NUM>. This driving principle is described hereinafter. Note that the driving principle of vibration actuator <NUM> according to the embodiment is achieved in all of the vibration actuators according to each of following embodiments.

In vibration actuator <NUM> according to the embodiment, movable body <NUM> vibrates at resonant frequency fr [Hz] calculated by following Expression (<NUM>) with respect to fixing body <NUM>, where moment of inertia of movable body <NUM> is J [Kgm<NUM>] m [kg], and spring constant in a twisting direction of plate spring part <NUM> is Ksp.

Vibration actuator <NUM> of the embodiment supplies an alternating current of a frequency nearly equivalent to resonance frequency fr of movable body <NUM> to coil <NUM> from the power supply part. Coil <NUM> is energized thereby, and movable body <NUM> can be moved efficiently.

Movable body <NUM> of vibration actuator <NUM> is in a state being supported in a spring-mass system structure supported by fixing body <NUM> via plate spring part <NUM>. Therefore, when an alternating current of a frequency equivalent to resonance frequency fr of movable body <NUM> is supplied to coil <NUM>, movable body <NUM> is driven in a highly efficient resonance state.

An equation of motion and an equation of circuit indicating the driving principle of vibration actuator <NUM> are presented hereinafter. Vibration actuator <NUM> is driven based on the equation of motion written as following Expression (<NUM>) and the equation of circuit written as following Expression (<NUM>).

That is, moment of inertia J [Kgm<NUM>], rotation angle θ(t) [rad], torque constant Kt [Nm/A], electric current i(t) [A], spring constant Ksp [Nm/rad], damping coefficient D [Nm/(rad/s)], and the like in actuator <NUM> can be changed as appropriate within a range satisfying Expression (<NUM>). Further, electric voltage e(t) [V], resistance R [Ω], inductance L [H], and back electromotive force constant Ke [V/(rad/s)] can be changed as appropriate within a range satisfying Expression (<NUM>).

As described, large output can be acquired efficiently when actuator <NUM> is driven at resonance frequency fr that is determined according to moment of inertia J of movable body <NUM> and spring constant Ksp of plate spring part (elastic body) <NUM>.

Conventionally, in a configuration in which a movable body is supported to be oscillatable with respect to a fixing body by using a plate spring, the plate spring is attached to be extended from an outer edge of both ends of the movable body isolated in the vibration direction toward a direction orthogonal to (direction crossing with) the vibration direction parallel to the bottom face of the fixing body. In case of such configuration, for stably oscillating the movable body, the plate spring is provided at least to extend in the direction orthogonal to the vibration direction from each of both ends for support by the fixing body. That is, in the vibration actuator in the conventional plate spring support configuration, the plate spring supporting the movable body to be oscillatable with respect to the fixing body is connected at a plurality of points with each of the fixing body and the movable body. Because of such configuration, a wider design space for the plate spring is required, so that it is difficult to reduce the size of the actuator. Further, the configuration of the plate spring becomes complicated, thereby making it harder to achieve efficient manufacture.

Meanwhile, in vibration actuator <NUM> of the embodiment, movable body <NUM> is fixed to one end of a single plate spring part <NUM> and fixing body <NUM> is fixed to the other end of plate spring part <NUM> to support movable body <NUM> to be oscillatable, that is, to be vibratable. Thereby, compared to the conventional configuration in which the plate spring part is fixed to the movable body and the fixing body at a plurality of points, the configuration and design are simpler and space can be saved, so that vibration actuator <NUM> itself can be reduced in size.

Further, with the conventional vibration actuator, there is a restriction in the mounting direction depending on the product shapes to be incorporated and the mounting space. For example, when the vibration actuator is incorporated in a product to be placed on the skin of a user when the user wears the product, the height of the vibration actuator with respect to the skin to be actually placed is designed to be as low as possible in terms of a feeling of wearing the product. That is, there is also a restriction of the mounting direction of the product on the excitation direction for movable body <NUM> by cooperation of first magnet <NUM>, second magnet <NUM>, and coil <NUM>. Especially, in the vibration actuator capable of generating vibrations in the lateral direction that is the direction perpendicular to the skin as the mounting face, there is a restriction in design of the spring. Therefore, there is a restriction in securing the mass of the movable part and in the spring design space, so that it becomes difficult to achieve high output.

In this regards, every time movable body <NUM> of vibration actuator <NUM> oscillates, movable body <NUM> alternately contacts (specifically collides) with base plate <NUM> and top plate <NUM> of cover <NUM> via contact part <NUM> to vibrate casing <NUM> itself of vibration actuator <NUM>.

Thereby, vibration actuator <NUM> can allow the user to feel larger vibrations than the vibrations generated by an actual excitation force applied to movable body <NUM> via casing <NUM>.

Therefore, vibration actuator <NUM> has such an advantage that preferable vibrations can be given to the skin as the mounting target through applying the excitation force to the perpendicular direction with respect to the mounting direction of the product to be incorporated even with the vibration actuator in which the excitation direction is the lateral direction.

Further, in movable body <NUM>, first magnet <NUM>, second magnet <NUM>, and coil <NUM> are disposed at base-end side (end side where plate spring part <NUM> is joined) portion 30a (see <FIG>) of entire movable body <NUM>, and weight <NUM> is disposed at tip side portion 30b of movable body <NUM>. That is, in movable body <NUM>, a magnetic circuit generating a driving torque of movable body <NUM> is disposed on an oscillation fulcrum side, and a weight is disposed on the tip side of movable body <NUM> where the displacement range is the greatest at the time of oscillation. Thereby, compared to the configuration in which first magnet <NUM>, second magnet <NUM>, and coil <NUM> are disposed on the tip side of movable body <NUM>, a ratio of weight <NUM> occupying the tip side becomes greater. Therefore, rotation moment (mass in a rotation system) given to movable body <NUM> is increased, so that it is possible to achieve high output of vibrations.

Further, in vibration actuator <NUM>, coil <NUM> is disposed on movable body <NUM>, first magnet <NUM> and second magnet <NUM> are disposed on fixing body <NUM>, and movable body <NUM> is driven by the Lorentz force generated according to Fleming's left hand rule. Thereby, even when the external shape dimensions of casing <NUM> of vibration actuator <NUM> are restricted, a magnetic force can be generated with a minimum space of the restricted dimensions. For example, when a coil and a core around which the coil is wound are provided in a case of the so-called magnet movable configuration in which a magnet is disposed on a movable body side, it is necessary to dispose the coil and the core to surround the magnet disposed on the movable body or to dispose the coil and the core on the movable body side of the magnet. In any of such coil and core dispositions, the layout space of the coil and the core becomes larger so that the space for the movable body becomes smaller within the casing of the restricted external shape. Therefore, the movable body becomes lighter, so that the output may be deteriorated.

Further, compared to the conventional vibration actuator that involves sliding with the fixing body for vibrating the movable body, movable body <NUM> vibrates without sliding with a part of fixing body <NUM>, so that attenuation of the thrust due to the frictional resistance with the fixing body does not occur at the time of vibrations and a preferable amplitude can be acquired.

<FIG> is an external view illustrating a configuration of a vibration actuator according to Embodiment <NUM> of the present invention, <FIG> is a perspective view illustrating a state where a cover is removed from the vibration actuator, and <FIG> is an exploded perspective view of the vibration actuator. <FIG> is a longitudinal sectional view of the configuration of main components of the vibration actuator, <FIG> is a diagram illustrating the configuration of a magnetic circuit of the vibration actuator, and <FIG> is a longitudinal sectional view illustrating actions of a movable body in the vibration actuator.

Vibration actuator 100A illustrated in <FIG> includes casing 11A of a cuboid external shape formed with base plate 12A and cover 13A. The shape of casing 11A in vibration actuator 100A of the embodiment is formed such that, among a height, a width, and a depth, the depth becomes the longest and the height becomes the shortest in any dimensions. Like casing <NUM>, casing 11A may not be in a cuboid shape but may be in any other shapes such as a cubic shape as long as it is a shape capable of housing movable body 30A movably.

Vibration actuator 100A includes: fixing body 10A including casing 11A; movable body 30A that vibrates (one end side reciprocally oscillates) with respect to fixing body 10A inside casing 11A; and plate spring part 50A as a plate-like elastic body.

Note that vibration actuator 100A has similar basic configuration as that of vibration actuator <NUM> according to Embodiment <NUM>, and mainly the shape of plate spring part 50A and the damper shape are different compared to those of vibration actuator <NUM>. Hereinafter, same names and same reference numerals with "A" added thereto are applied to the same structural components as the structural components of vibration actuator <NUM>, and description thereof is omitted as appropriate.

In vibration actuator 100A, a second end portion of movable body 30A facing base plate 12A supported by plate spring part 50A on the first end portion reciprocally vibrates in the height direction with respect to base plate 12A.

Specifically, fixing body 10A includes base plate 12A, cover 13A, first magnet holder 14A, second magnet holder 15A, first magnet 21A, and second magnet 22A. Movable body 30A includes coil 40A, main body part 31A (coil holder 32A and weight 34A), and contact parts 81A, and movable body 30A is provided to be freely oscillatable to fixing body 10A via plate spring part 50A provided between fixing body 10A and movable body 30A.

Base plate 12A is formed in a rectangular shape, has movable body 30A disposed on its surface side by being isolated therefrom, and configures hollow casing 11A together with cover 13A. First end portion <NUM> of base plate 12A according to the embodiment is projected to outside from casing 11A, and a second end portion of power supply part <NUM> connected on one end side to coil 40A inside casing 11A is disposed thereon. Power supply part <NUM> is a substrate supplying the electric power to coil 40A, and formed with a substrate such as a flexible printed circuit (FPC) connected to an external power via the second end portion exposed to outside casing 11A.

Base plate 12A is formed with a plate material along with cover 13A to be described later, and functions as an electromagnetic shield.

First magnet 21A is fixed on base plate 12A via first magnet holder 14A.

First magnet holder 14A has a similar function as first magnet holder <NUM> of actuator <NUM>, and locates and fixes first magnet 21A on base plate 12A. First magnet holder 14A in the embodiment is formed in a flat rectangular frame shape surrounding first magnet 21A, and first magnet 21A is disposed inside thereof. First magnet holder 14A in the embodiment is disposed such that first magnet 21A comes to be positioned on base-end portion 30Aa side of movable body 30A. First magnet 21A formed in the manner described above is inserted into coil 40A of movable body 30A like first magnet <NUM> of actuator <NUM> according to Embodiment <NUM>.

Cover 13A together with base plate 12A has a function similar to that of cover <NUM> and base plate <NUM> of actuator <NUM> according to Embodiment <NUM>. Cover 13A is attached to cover base plate 12A, and houses movable body 30A to be freely movable inside casing 11A that is formed together with base plate 12A. Top plate 131A of cover 13A is disposed by opposing to base plate 12A with movable body 30A interposed therebetween.

Second magnet 22A located by second magnet holder 15A is fixed to top plate 131A of cover 13A. Note that the function of top plate 131A as a yoke is similar to that of top plate <NUM>.

Like second magnet holder <NUM> of actuator <NUM>, second magnet holder 15A locates second magnet 22A formed in the same manner as that of first magnet 21A at a position opposing to first magnet 21A.

Like second magnet <NUM> of actuator <NUM>, as illustrated in <FIG> and <FIG>, second magnet 22A is disposed opposingly right above first magnet 21A and with a space provided therebetween with the magnetization direction set different from the magnetization direction of first magnet 21A. That is, second magnet 22A is disposed opposite to first magnet 21A with the same magnetic polarity. Further, in the embodiment, an opposing part of second magnet 22A and first magnet 21A is inserted into coil 40A of movable body 30A while being isolated from inner peripheral face of coil 40A.

Compared to movable body <NUM>, movable body 30A is different mainly in plate spring part 50A, the attaching structure of plate spring part 50A, and contact parts 81A. That is, in movable body 30A, coil 40A and main body part 31A are joined side by side in a direction (front-and-back direction in <FIG>) orthogonal to the magnetization direction of first magnet 21A and second magnet 22A.

Coil 40A together with first magnet 21A and second magnet 22A generates a magnetic force to electromagnetically drive movable body 30A. Coil 40A is disposed on an outer periphery side of first magnet 21A and second magnet 22A with a prescribed space provided therebetween surrounding the top face of first magnet 21A and the lower face of second magnet 22A opposing to each other.

Like coil <NUM> of actuator <NUM>, coil 40A has a shape fitting external shapes of first magnet 21A and second magnet 22A, and disposed to be wound around the periphery of first magnet 21A and second magnet 22A in the direction orthogonal to the magnetization direction of first magnet 21A and second magnet 22A. The positional relation of coil 40A, first magnet 21A, and second magnet 22A is similar to that of Embodiment <NUM>, so that description thereof is omitted.

Power supply part <NUM> is connected to coil 40A. Coil 40A is attached to main body part 31A of movable body 30A via coil holder 32A.

Power supply part <NUM> is a substrate supplying the electric power to coil 40A. Power supply part <NUM> herein is a flexible printed circuit (FPC). In the embodiment, power supply part <NUM> is disposed such that a flexible part overlaps on an upper side of plate spring part 50A on a base end side of movable body <NUM>. First end portion <NUM> on one side of the flexible part is connected to coil 40A via wire <NUM> on movable body 30A side. Second end portion <NUM> on the other side of the flexible part of power supply part <NUM> is provided on first end portion <NUM> of base plate 12A, and exposed to outside of casing 11A in the longitudinal direction. Note that a drive circuit may be mounted on power supply part <NUM>, and an electric power supplied from an external power source connected outside is supplied to coil 40A to generate a magnetic force. Power supply part <NUM> follows move of movable body <NUM> at the flexible part.

Main body part 31A includes a first end portion to which plate spring part 50A as an elastic body is attached and a second end portion as a free end. Main body part 31A in the embodiment is configured with coil holder 32A and weight 34A.

Coil holder 32A fixes movable body fixing part 55A as the second end portion of plate spring part 50A to movable body 30A, and holds coil 40A.

Coil holder 32A in the embodiment is formed in a rectangular frame shape to have coil 40A disposed on an inner side of the frame part, and fixes coil 40A at an outer periphery face thereof. Like coil holder <NUM> of Embodiment <NUM>, coil holder 32A is formed by processing a sheet metal made with stainless material. Like coil holder <NUM>, coil holder 32A may be formed with a material of high specific gravity (specific gravity of about <NUM> to <NUM>) such as tungsten that is of high specific gravity as long as it is capable of being formed into the above shape and dimensions. In such case, the mass of the movable body can be increased because of the high specific gravity.

Movable body fixing part 55A of plate spring part 50A is fixed at an upper end face of coil holder 32A, and weight 34A is adjacently fixed at the other side face on the opposite side of the side where plate spring part 50A is extruded. Movable body 30A carries coil 40A on one end side of movable body 30A while carrying weight 34A on the other end side.

Like weight <NUM>, weight 34A is a weight provided to movable body 30A supported by plate spring part 50A as a plate-like elastic body to increase output of vibrations of movable body 30A. Weight 34A in the embodiment is attached to extend in a direction orthogonal to the axis of the coil from coil holder 32A and to an inverse side of the direction where plate spring part 50A extends on fixing body 10A side.

Weight 34A is formed with a material of high specific gravity such as tungsten that is of higher specific gravity than a material such as SECC. Thereby, when it is desired to increase the mass of movable body 30A whose external shape dimensions are set in design and the like, weight 34A may be formed with a high specific gravity material with the specific gravity of about <NUM> to <NUM> so that the mass for the specific gravity can be included in the mass of the movable body. As a result, the output of vibrations of movable body 30A can be increased.

Weight 34A is in a plate-like cuboid shape and, in the embodiment, formed in the same thickness as the height of coil holder 32A. Thereby, upper end faces of coil holder 32A and weight 34A are flush with each other, and lower end faces thereof are flush with each other.

Contact parts 81A are attached at tip ends (top and bottom faces of tip end) of weight 34A in the oscillation directions, that is, in approaching and leaving directions with respect to base plate 12A and top plate 131A herein by opposing to base plate 12A and top plate 131A.

Contact parts 81A are dampers, and abut against base plate 12A and top plate 131A of cover 13A when movable body 30A oscillates.

Plate spring part 50A is formed with a plate-like elastic body and, in the embodiment, formed with a plate spring. Plate spring part 50A is formed to have a substantially U-shape in sectional view such that one end to be fixed to fixing body 10A and the other end to be fixed to movable body <NUM> are isolated and opposed to each other.

Plate spring part 50A in the embodiment is formed by bending a long plate into a U-shape, and includes fixing body fixing part 51A to be fixed to fixing body 10A, elastically deformable arm part 53A, and movable body fixing part 55A to be fixed to movable body 30A.

As illustrated in <FIG>, fixing body fixing part 51A is fixed on the first end portion side of the surface of base plate 12A by bonding, welding, or the like inside cover 13A. Arm part 53A includes rising plate part 531A extruded out to rise upward from the base end side of actuator 100A at fixing body fixing part 51A, and bending plate part 533A bent from rising plate part 531A to the tip side of actuator 100A along base plate 12A. Movable body fixing part 55A is formed on a same plane with bending plate part 533A continuously from the tip of bending plate part 533A. At least one of bending plate part 533A and movable body fixing part 55A opposes to fixing body fixing part 51A.

Movable body fixing part 55A is formed in a frame shape fitting the shape of coil holder 32A, and disposed opposite to fixing body fixing part 51A. Movable body fixing part 55A comes in surface-contact with the upper end face of the frame shape of coil holder 32A and fixed by bonding, welding, or the like. Inside frame-shaped movable body fixing part 55A, second magnet 22A to be inserted into the inner side of coil 40A fixed to coil holder 32A is inserted and removed.

Through plate spring part 50A, movable body 30A is disposed inside casing 11A at an intermediate position between base plate 12A and top plate 131A of cover 13A by being cantilevered substantially in parallel to each of base plate 12A and top plate 131A.

That is, in plate spring part 50A of the embodiment, fixing body fixing part 51A and at least one of bending plate part 533A and movable body fixing part 55A are disposed opposite to each other in parallel. Thereby, when attaching plate spring part 50A to fixing body 10A, it is unnecessary to secure the space for placing plate spring part 50A itself in the longitudinal direction of actuator 100A, that is, in the front-and-back direction. Therefore, more reduction in the size of actuator 100A itself can be achieved without decreasing the driving performance.

In vibration actuator 100A of Embodiment <NUM> as described above, movable body 30A is disposed to be oscillatable by having its one end side elastically supported by plate spring part 50A between base plate 12A of fixing body 10A and top plate 131A of cover 13A. In addition, first magnet 21A and second magnet 22A are disposed in coil 40A of movable body 30A, and fixed to base plate 12A and top plate 131A by having magnetic pole faces of the same polarity (N-pole faces in <FIG>) opposed to each other.

Vibration actuator 100A includes a magnetic circuit similar to that of vibration actuator <NUM> for electromagnetical driving similar to vibration actuator <NUM>.

Through supplying electric power from the power supply part to energize coil 40A, movable body 30A is reciprocally vibrated in the height direction (lateral direction), that is, in approaching and leaving directions with respect to base plate 12A. Thereby, a second end portion of movable body 30A is oscillated.

For example, on vibration actuator 100A, generated is flow B of magnetic flux illustrated in <FIG>. When power is supplied to coil 40A in vibration actuator 100A, an electric current flows in coil 40A that is disposed to be orthogonal to the magnetic flux from first magnet 21A and second magnet 22A. By the Lorentz force generated thereby, thrust F is generated in coil 40A based on Fleming's left hand rule so that movable body 30A is driven in F direction. Thereby, movable body 30A is supported by plate spring part 50A on the first end portion side, so that, like movable body 300A illustrated in <FIG> with a broken line, the second end portion of movable body 30A, that is, weight 34A side, oscillates with one end side as the fulcrum (herein, oscillates in F1 direction). Thereby, movable body 30A comes in a state illustrated with broken line 300A, and contacts (specifically collides) with top plate 131A of cover 13A via contact part 81A.

Further, when an electric current changed to an inverse direction is supplied to coil 40A (when the flowing direction of the electric current in <FIG> is inversed), coil 40A returns to the reference position at the time of change, -F thrust is generated in coil 40A by the Lorenz force, and movable body 30A is driven to move in -F1 direction that is exactly opposite from F1 direction. Movable body 30A is supported by plate spring part 50A at its one end side, so that the other end of movable body 30A, that is, weight 34A side oscillates (moves in -F1 direction) and collides with base plate 12A via contact part 81A (a state of movable body 300B illustrated in <FIG> with a broken line).

That is, in vibration actuator 100A, coil 40A is energized by an alternating current wave input to coil 40A from power supply part <NUM>, and a magnetic attraction force and a repulsive force are effectively generated to first magnet 21A on fixing body 10A side and second magnet 22A. Thereby, coil 40A on movable body 30A side acquires the thrust in F direction and -F direction with respect to the position to be the driving reference position (herein, the position at which the center position of coil 40A in the height direction comes on substantially the same horizontal plane with the intermediate position between the opposing magnetic pole faces of the same polarity of first magnet 21A and second magnet 22A) (see <FIG>). Coil 40A of movable body 30A reciprocally vibrates in F direction and -F direction along the height direction. That is, movable body 30A reciprocally vibrates with respect to fixing body 10A in an arc form in a direction orthogonal to base plate 12A. This driving principle is the same as that of actuator <NUM> according to Embodiment <NUM> and achieved by Expression (<NUM>) to (<NUM>) described above, so that description thereof is omitted.

With the embodiment, effects similar to those of actuator <NUM> according to Embodiment <NUM> can be acquired.

Especially, in vibration actuator 100A, movable body 30A is fixed to one end of a single plate spring part 50A and fixing body 10A is fixed to the other end of plate spring part 50A to support movable body 30A to be oscillatable, that is, to be vibratable. Thereby, compared to the conventional configuration in which the plate spring part is fixed to the movable body and the fixing body at a plurality of points, the configuration and design are simpler and space can be saved, so that vibration actuator 100A itself can be reduced in size.

Further, every time movable body 30A of vibration actuator 100A oscillates, movable body 30A is brought in contact (specifically to collide) alternately with base plate 12A and top plate 131A of cover 13A via contact parts 81A to vibrate casing 11A itself of vibration actuator 100A.

Thereby, vibration actuator 100A can allow the user to feel larger vibrations than the vibrations generated by an actual excitation force applied to movable body 30A via casing 11A. Therefore, vibration actuator 100A has such an advantage that preferable vibrations can be given to the skin as the mounting target through applying the excitation force to the perpendicular direction with respect to the mounting direction of the product to be incorporated even with the vibration actuator in which the excitation direction is the lateral direction.

Further, like vibration actuator <NUM>, in movable body 30A of vibration actuator 100A, first magnet 21A, second magnet 22A, and coil 40A are disposed at base-end side (end side where plate spring part 50A is joined) portion 30aA (see <FIG>) of entire movable body 30A. First and second magnets 21A, 22A and coil 40A form a magnetic circuit as an electromagnetic driving section that generates the driving torque of movable body 30A. Weight 34A is disposed at tip side portion 30bA of movable body 30A. Thereby, compared to the configuration in which first magnet 21A, second magnet 22A, and coil 40A are disposed on the tip side of movable body 30A, rotation moment (mass in a rotation system) given to movable body 30A is increased. Therefore, it is possible to achieve high output of vibrations.

Further, like vibration actuator <NUM>, even when the external shape dimensions of casing 11A of vibration actuator 100A are restricted, a magnetic force can be generated with a minimum space of the restricted dimensions. Meanwhile, a ratio of weight 34A occupying the tip side becomes greater in movable body 30A and rotation moment is increased, so that it is possible to achieve high output. Further, there is no attenuation of the thrust generated due to the frictional resistance with the fixing body at the time of vibration, so that it is possible to acquire a preferable amplitude.

In addition, in actuator 100A, plate spring part 50A is formed in a U-shape. That is, in plate spring part 50A, fixing body fixing part 51A is disposed on a side closer to movable body fixing part 55A than arm part 53A between movable body fixing part 55A and fixing body fixing part 51A and fixed to base plate 12A. Thereby, length of a vibration generation system of base plate 12A, plate spring part 50A, and movable body 30A in the longitudinal direction can be shortened compared to the configuration in which fixing body fixing part 51A is disposed on a side closer to the base end than arm part 53A.

<FIG> is an external view illustrating a configuration of a vibration actuator according to Embodiment <NUM> of the present invention, <FIG> is a perspective view illustrating a state where a cover is removed from the vibration actuator, and <FIG> is an exploded perspective view of the vibration actuator. Further, <FIG> is a longitudinal sectional view of the configuration of main components of the vibration actuator, and <FIG> is a longitudinal sectional view illustrating actions of a movable body in the vibration actuator.

Differences in the basic configuration of actuator 100B according to Embodiment <NUM> illustrated in <FIG> with respect to actuators <NUM> and 100A are that coil 40B is provided to fixing body 10B, and magnet <NUM> is provided to movable body 30B.

Vibration actuator 100B has the basic configuration similar to that of vibration actuator <NUM> of Embodiment <NUM>, and mainly coil 40B, the shape of plate spring part 50B, and the damper shape are different compared to vibration actuator <NUM> other than the difference in the attaching positions of coil 40B and magnet <NUM>. Therefore, hereinafter, same names and same reference numerals with "B" added thereto are applied to the same structural components as the structural components of vibration actuator <NUM>, and description thereof is omitted as appropriate.

Vibration actuator 100B illustrated in <FIG> includes casing 11B of a cuboid external shape formed with base plate 12B and cover 13B. The shape of casing 11B in vibration actuator 100B of the embodiment is formed such that, among a height, a width, and a depth, the depth becomes the longest and the height becomes the shortest in any dimensions. Like casing <NUM>, casing 11B may not be in a cuboid shape but may be in any other shapes such as a cubic shape as long as it is a shape capable of housing movable body 30B movably.

Vibration actuator 100B includes: fixing body 10B including casing 11B; movable body 30B that vibrates (one end side reciprocally oscillates) with respect to fixing body 10B inside casing 11B; and plate spring part 50B as a plate-like elastic body.

Like vibration actuators <NUM> and 100A, in vibration actuator 100B, one end of movable body 30B facing base plate 12B and has the other end supported by plate spring part 50B on the first end portion side reciprocally vibrates in the height direction with respect to base plate 12B.

Fixing body 10B includes base plate 12B, cover 13B, and coil 40B. Movable body 30B includes magnet <NUM>, main body part 31B (yoke 32B and weight 34B), and contact parts 81B, and provided to be freely oscillatable with respect to fixing body 10B via plate spring part 50B provided between fixing body 10B and movable body 30B.

Base plate 12B is formed in a rectangular shape lengthy in the depth direction, has movable body 30B disposed on its surface side by being isolated therefrom, and configures hollow casing 11B together with cover 13B that covers movable body 30B. First end portion 122B of base plate 12B according to the embodiment is projected to outside from casing 11B, and coil wire 40a extruded out from coil 40B may be connected to a power supply part, not illustrated, on first end portion 122B to supply the electric power to coil 40B from the power supply part. Like the case of actuator <NUM>, base plate 12B is formed with a plate material exhibiting conductivity together with cover 13B to be described later and functions as an electromagnetic shield.

On the first end portion side of the surface of base plate 12B, coil 40B is fixed with the winding direction facing toward the perpendicular direction with respect to the surface of base plate 12B.

Coil 40B together with magnet <NUM> generates a magnetic force to electromagnetically drive movable body 30B. Coil 40B is disposed on an outer periphery side of magnet <NUM> with a prescribed space provided therebetween surrounding the lower part of magnet <NUM> on movable body 30B side. Like coil <NUM> of actuator <NUM>, coil 40B has a shape fitting the external shape of magnet <NUM>, and is formed in an angular cylindrical shape herein.

Cover 13B together with base plate 12B has a function similar to that of cover <NUM> and base plate <NUM> of actuator <NUM> according to Embodiment <NUM>. Cover 13B is attached to cover base plate 12B, and houses movable body 30B to be freely movable inside casing 11B that is formed together with base plate 12B. Top plate 131B of cover 13B is disposed by opposing to base plate 12B with movable body 30B interposed therebetween. Herein, top plate 131B is disposed in parallel to base plate 12B.

Compared to movable body <NUM>, movable body 30B is different mainly in plate spring part 50B, an attaching configuration of plate spring part 50B, and contact parts 81B, and includes the magnet instead of the coil. That is, movable body 30B includes magnet <NUM> and main body part 31B.

In main body part 31B, yoke 32B having a first end portion to which plate spring part 50B as an elastic body is attached and weight 34B configuring a free end side may be disposed adjacent to each other and joined. Yoke 32B and weight 34B together with magnet <NUM> are joined to movable body fixing part 55B by being adjacent to each other in the front-and-back direction.

Yoke 32B together with magnet <NUM> is joined to movable body fixing part 55B on the first end portion side of movable body 30B. Yoke 32B is formed in a rectangular frame shape, and disposed with an opening direction facing toward the direction opposing to base plate 12B. Yoke 32B is fixed at its upper-end opening fringe part to movable body fixing part 55B as a second end portion of plate spring part 50B, and disposed at its lower-end opening fringe part facing toward base plate 12B side. Yoke 32B is fixed to movable body fixing part 55B surrounding magnet <NUM> disposed inside thereof with a prescribed space provided therefrom. The prescribed space between yoke 32B and the periphery of magnet <NUM> is a space to which coil 40B can be inserted in the top-and-bottom direction, that is, the moving direction. Specifically, it is the space with which coil 40B can be inserted between yoke 32B and magnet <NUM> without contacting each of those when movable body 30B makes an arc motion. As illustrated in <FIG>, the lower end of yoke 32B opposes to the outer circumference of the upper end of coil 40B with a prescribed space provided in a horizontal direction. Note that yoke 32B is formed in the same thickness (length in the vibration direction) as that of weight 34B.

Magnet <NUM> is disposed to be capable of being inserted into and removed from coil 40B, and disposed on an inner side of yoke 32B in movable body 30B via movable body fixing part 55B.

It is preferable for magnet <NUM> to be disposed such that the magnetization direction is in parallel or on a same plane with the winding axis of coil 40B.

Like weight <NUM>, weight 34B is a weight provided to movable body 30B supported by plate spring part 50B as a plate-like elastic body to increase output of vibrations of movable body 30B. Weight 34B in the embodiment is attached to yoke 32B in a direction orthogonal to the winding axis of coil 40B and to extend to an inverse side of the direction where plate spring part 50B extends on fixing body 10B side.

Note that weight 34B is formed with a material of high specific gravity such as tungsten that is of higher specific gravity than a material such as SECC. Thereby, when it is desired to increase the mass of movable body 30B whose external shape dimensions are set in design and the like, weight 34B may be formed with a high specific gravity material with the specific gravity of about <NUM> to <NUM> so that the mass for the specific gravity can be included in the mass of the movable body. As a result, the output of vibrations of movable body 30B can be increased.

Weight 34B is welded at the tip (second end portion) of movable body fixing part 55B.

Like actuators <NUM> and 100A, at the tip of weight 34B, contact parts 81B are attached at end faces (top and bottom faces of the tip end) in the oscillation directions, that is, in approaching and leaving directions with respect to base plate 12B and top plate 131B herein by opposing to base plate 12B and top plate 131B.

Contact parts 81B are dampers, and abut against base plate 12B and top plate 131B of cover 13B when movable body 30B oscillates. Operations and effects of contact parts 81B are similar to those of contact parts <NUM> and 81A, so that description thereof is omitted.

Plate spring part 50B is formed with a plate-like elastic body and, in the embodiment, formed with a plate spring.

Specifically, plate spring part 50B is formed by bending a long plate, and includes fixing body fixing part 51B to be fixed to fixing body 10B, elastically deformable arm part 53B, and movable body fixing part 55B to be fixed to movable body 30B.

As illustrated in <FIG>, fixing body fixing part 51B is fixed on the first end portion side of the surface of base plate 12B by bonding, welding, or the like inside cover 13B. Arm part 53B includes rising plate part 531B extruded out to rise upward from the base end side of actuator 100B at fixing body fixing part 51B, and bending plate part 533B bent from rising plate part 531B to the tip side of actuator 100B along base plate 12B. Movable body fixing part 55B is formed on a same plane with bending plate part 533B continuously from the tip of bending plate part 533B.

Movable body fixing part 55B is formed in a plate shape fitting the external shape of yoke 32B. At least one of movable body fixing part 55B and bending plate part 533B opposes to fixing body fixing part 51B.

Movable body fixing part 55B comes in surface-contact with the upper end face of the frame shape of yoke 32B and is fixed by bonding, welding, or the like, and fixes magnet <NUM> at a first end portion (upper end) in the magnetization direction inside yoke 32B.

Through plate spring part 50B, movable body 30B is disposed inside casing 11B at an intermediate position between base plate 12B and top plate 131B of cover 13B by being cantilevered substantially in parallel to each of base plate 12B and top plate 131B.

That is, in plate spring part 50B of the embodiment, fixing body fixing part 51B and at least one of bending plate part 533B and movable body fixing part 55B are disposed opposite to each other in parallel. Thereby, when attaching plate spring part 50B to fixing body 10B, it is unnecessary to secure the space for placing plate spring part 50B itself in the longitudinal direction of actuator 100B, that is, in the front-and-back direction. Therefore, more reduction in the size of actuator 100B itself can be achieved without decreasing the driving performance.

Vibration actuator 100B includes a magnetic circuit similar to that of vibration actuator <NUM> for electromagnetical driving similar to vibration actuator <NUM>.

Through supplying electric power from the power supply part to energize coil 40B, movable body 30B is reciprocally vibrated in the height direction (lateral direction), that is, in approaching and leaving directions with respect to base plate 12B. Thereby, the second end portion of movable body 30B is oscillated.

For example, on vibration actuator 100B, generated is flow B2 of magnetic flux illustrated in <FIG>. When power is supplied to coil 40B in vibration actuator 100B, an electric current flows in coil 40B that is disposed to be orthogonal to the magnetic flux from magnet <NUM>. A repulsive force of the force generated in coil 40B based on Fleming's left hand rule by the Lorentz force generated thereby works as the thrust in F direction on magnet <NUM> of movable body 30B, so that movable body 30B is driven in F direction.

Movable body 30B is supported by plate spring part 50B on the first end portion side, so that, like movable body 300C illustrated in <FIG> with a broken line, a second end portion of movable body 30B on weight 34B side, that is, the tip end oscillates in F2 direction with one end side, that is, the based end side as the fulcrum. Thereby, the tip end on the free end side of movable body 30B collides with top plate 131B of cover 13B via contact part 81B (<FIG> illustrates a state where movable body 300C illustrated with a broken line collides, that is, contacts with top plate 131B via contact part 81B).

Further, when an electric current changed to an inverse direction is supplied to coil 40B (when the flowing direction of the electric current in <FIG> is inversed), coil 40B returns to the reference position at the time of change, and a repulsive force of the thrust generated in coil 40B by the Lorentz force works on magnet <NUM> as the -F thrust. Thereby, movable body 30B is driven in -F2 direction that is exactly opposite from F2 direction. Movable body 30B is supported by plate spring part 50B on the first end portion side, so that the second end portion of movable body 30B, that is, weight 34B side oscillates and moves in -F2 direction, and collides with base plate 12B via contact part 81B (a state of movable body 300D illustrated in <FIG> with a broken line).

That is, in vibration actuator 100B, coil 40B is energized by an alternating current wave input to coil 40B from a power supply part, and a magnetic attraction force and a repulsive force are effectively generated to magnet <NUM> on movable body 30B side. Thereby, magnet <NUM> on movable body 30B side acquires the thrust in F2 direction and -F2 direction with respect to the position to be the driving reference position (herein, the position at which the upper face of coil 40B is in the vicinity of the intermediate position in the magnetization direction of magnet <NUM>) (see <FIG>). Coil 40B reciprocally vibrates in F2 direction and -F2 direction along the height direction. That is, movable body 30B reciprocally vibrates with respect to fixing body 10B in an arc form in a direction orthogonal to base plate 12B. This driving principle is the same as that of actuator <NUM> according to Embodiment <NUM> and achieved by Expression (<NUM>) to (<NUM>) described above, so that description thereof is omitted.

Especially, in vibration actuator 100B, movable body 30B is fixed to one end of a single plate spring part 50B and fixing body 10B is fixed to the other end of plate spring part 50B to support movable body 30B to be oscillatable, that is, to be vibratable. Thereby, compared to the conventional configuration in which the plate spring part is fixed to the movable body and the fixing body at a plurality of points, the configuration and design are simpler and space can be saved, so that vibration actuator 100B itself can be reduced in size.

Further, every time movable body 30B of vibration actuator 100B oscillates, movable body 30B is brought to collide (contact) alternately with base plate 12B and top plate 131B of cover 13B via contact parts 81B to vibrate casing 11B itself of vibration actuator 100B.

Thereby, vibration actuator 100B can allow the user to feel larger vibrations than the vibrations generated by an actual excitation force applied to movable body 30B via casing 11B. Therefore, vibration actuator 100B has such an advantage that preferable vibrations can be given to the skin as the mounting target through applying the excitation force to the perpendicular direction with respect to the mounting direction of the product to be incorporated even with the vibration actuator in which the excitation direction is the lateral direction.

Further, like vibration actuator <NUM>, in vibration actuator 100B, magnet <NUM>, yoke 32B, and coil 40B (a magnetic circuit as an electromagnetic driving section that generates the driving torque of movable body 30B) are disposed at base end side (end side where plate spring part 50B is joined) portion 30aB (see <FIG>) of entire movable body 30B. Meanwhile, in movable body 30B, weight 34B is disposed at tip side portion 30bB of movable body 30B. Thereby, compared to the configuration in which the electromagnetic driving section that drives movable body 30B is disposed on the tip side of movable body 30B, rotation moment (mass in a rotation system) given to movable body 30B is increased. Therefore, it is possible to achieve high output of vibrations.

In addition, in actuator 100B, plate spring part 50B is formed in a U-shape. That is, in plate spring part 50B, fixing body fixing part 51B is disposed on a side closer to movable body fixing part 55B than arm part 53B between movable body fixing part 55B and fixing body fixing part 51B and fixed to base plate 12B. Thereby, length of a vibration generation system of base plate 12B, plate spring part 50B, and movable body 30B in the longitudinal direction can be shortened compared to the configuration in which fixing body fixing part 51B is disposed on a side closer to the base end than arm part 53B.

Further, in actuator 100B, magnet <NUM> is provided to movable body 30B and coil 40B is disposed on fixing body 10B to drive magnet <NUM> side by having the electromagnetic force or the repulsive force according to Fleming's left hand rule as the diving source. Thereby, connection between the coil and the power supply part becomes unnecessary, which may otherwise be required when moving the movable body by providing the coil to the movable body.

<FIG> is a schematic view illustrating the configuration of main components of wearable terminal <NUM> according to Embodiment <NUM> of the present invention. Wearable terminal <NUM> is used by being worn by users. Herein, wearable terminal <NUM> functions as the so-called wearable input device that notifies incoming calls of a connected communication terminal to the user wearing the terminal with vibrations.

Wearable terminal <NUM> illustrated in <FIG> includes: communication apparatus <NUM>; processor <NUM>; vibration actuator <NUM> as a driving apparatus; and casing <NUM>. Vibration actuator <NUM> employs one of vibration actuators <NUM>, 100A, and 100B according to each of Embodiments <NUM> to <NUM>. The bottom face of vibration actuator <NUM> is disposed to be adjacent to or in close contact with the inner peripheral face <NUM> of casing <NUM>. On wearable terminal <NUM>, one of vibration actuators <NUM>, 100A, and 100B according to each of Embodiments <NUM> to <NUM> is mounted.

Casing <NUM> is formed in a ring shape, and worn on a finger of the user herein. In this case, the bottom face of vibration actuator <NUM> is located to overlap with the pad of the finger as a wearing body part. Thereby, vibration actuator <NUM> is worn to be in close contact with the part where mechanoreceptors are concentrated.

Communication apparatus <NUM> is connected to a radio communication terminal such as a mobile phone (not illustrated), a smartphone, or a mobile game machine via radio communications, and receives signals from the radio communication terminal and outputs those to processor <NUM>.

Signals received in communication apparatus <NUM> from the radio communication terminal, for example, are incoming call signals and/or the like of the radio communication terminal received via a communication system such as Bluetooth (R).

Processor <NUM> converts the input signals to driving signals of vibration actuator <NUM> by a conversion circuit section (not illustrated) and outputs the converted signals to driving circuit section <NUM>. Driving circuit section <NUM> is connected to a power supply part (coil wire 40a, power supply part <NUM>) of vibration actuator <NUM> (<NUM>, 100A, 100B), and includes a circuit for driving vibration actuator <NUM> mounted thereon. Through supplying the driving signals from the driving circuit section <NUM> to vibration actuator <NUM>, vibration actuator <NUM> is driven.

Thereby, movable body <NUM>, 30A, or 30B (see <FIG>) is vibrated to vibrate wearable terminal <NUM>. In casing <NUM> of wearable terminal <NUM>, movable body <NUM>, 30A, or 30B reciprocally vibrates in a direction crossing with, specifically, in a direction orthogonal to the bottom face (corresponding to bottom face of base plate <NUM>, 12A, or 12B) of vibration actuator <NUM>. In vibration actuator <NUM>, 100A, or 100B, movable body <NUM>, 30A, or 30B contacts with base plate <NUM>, 12A, or 12B (see <FIG>) every time the movable body vibrates. Thereby, along with vibrations of movable body <NUM>, 30A, or 30B, the impact when contacting with base plate <NUM>, 12A, or 12B due to vibrations is transmitted to the finger of the user more directly via the bottom face as vibrations. That is, it is possible to give perpendicular vibrations to the surface of the skin of the finger or the like on which the wearable terminal is mounted, so that the vibrations felt through the body of the user can be increased still more without changing the external shape and without increasing the size of the vibratory device itself to be kept in a prescribed size compared to the configuration with which the vibration actuator vibrates along the back side of the finger.

Further, movable body <NUM>, 30A, or 30B contacts with fixing body <NUM>, 10A, or 10B via contact parts <NUM>, 81A, or 81B every time the movable body vibrates. This makes it possible to generate large vibrations. Further, because movable body <NUM>, 30A, or 30B reciprocally oscillates and contacts with fixing body <NUM>, 10A, or 10B, the amount of vibrations generated thereby becomes constant so that it is possible to supply a product with stable output of vibrations.

Note that wearable terminal <NUM> may be an incoming notification function device including communication apparatus <NUM>, processor <NUM>, and vibration actuator <NUM> as a driving apparatus. Thereby, the incoming notification function device may be a configuration in which incoming calls from outside acquired by a radio communication terminal such as a mobile phone, a smartphone, or a mobile game machine is informed to the user by driving the vibration actuator. In addition to the incoming call signals, vibrations corresponding to signals such as mails input to an information communication terminal from an external apparatus or vibrations according to operations of games may be increased as vibrations of vibration actuator <NUM> to be given to the users as the vibrations felt via the body. Further, a position detection section such as an acceleration sensor detecting positional information of wearable terminal <NUM> may be provided to wearable terminal <NUM>, and processor <NUM> may vibrate vibration actuator <NUM> according to the positional information of wearable terminal <NUM> detected by the position detection section while transmitting the positional information of wearable terminal <NUM> to outside via communication apparatus <NUM>. Thereby, for example, by wearing wearable terminal <NUM> on the wrist or the finger of the user and simply moving the wrist or the finger to draw a character in the air, wearable terminal <NUM> vibrates in accordance with the movement, that is, in accordance with the position of wearable terminal <NUM> and characters or numerals formed based on the detected positional information can be input to the apparatus connected wirelessly. Further, it is also possible to connect to a display apparatus and to provide a function capable of displaying incoming calls from outside on the connected display apparatus such as a display and selecting information displayed on the display apparatus so as to drive vibration actuator <NUM> by processor <NUM> by corresponding to the selection.

For example, as illustrated in <FIG>, similar effects can be achieved through mounting actuator <NUM> that employs one of vibration actuator <NUM>, 100A, or 100B according to each of Embodiments <NUM> to <NUM> on mobile terminal <NUM>. Like wearable terminal <NUM>, mobile terminal <NUM> includes, inside casing <NUM>: communication apparatus <NUM>, processor <NUM>, driving circuit section <NUM>, and vibration actuator <NUM> as a driving apparatus. With mobile terminal <NUM>, it is possible to process signals of each function of mobile terminal <NUM> by processor <NUM> and vibrate vibration actuator <NUM> via driving circuit section <NUM> to notify the user in addition to notifying incoming calls from outside acquired by a radio communication terminal such as a mobile phone, a smartphone, or a mobile game machine through vibrating vibration actuator <NUM>.

While vibration actuators <NUM> and 100A according to each of Embodiments <NUM> and <NUM> are configured by using two magnets (first magnets <NUM>, 21A and second magnets <NUM>, 22A), the configuration is not limited only to that. It is also possible to employ a configuration that uses only the first magnets <NUM>, 21A or the second magnets <NUM>, 22A disposed with the same polarity opposing to each other.

When casings <NUM>, 11A, and 11B do not have the part corresponding to top plates <NUM>, 131A, and 131B in each of vibration actuators <NUM>, 100A, and 100B, movable bodies <NUM>, 30A, and 30B reciprocally vibrate in approaching and leaving directions with respect to the part corresponding to base plates <NUM>, 12A, and 12B.

It should be understood that the embodiments disclosed herein are illustrative and not restrictive in any respect, since the scope of the invention is defined by the appended claims rather than by the above description, and all changes that fall within metes and bounds of the appended claims or equivalence of such metes and bounds thereof, are therefore intended to be embraced. While the embodiments of the present invention have been described above, those embodiments are presented by way of examples of the preferred embodiments of the present invention and not intended to limit the scope of the present invention. That is, descriptions of configurations of the apparatus and shapes of each component are to be construed as illustrative only, and it is apparent that various changes and modifications are possible without departing from the scope of the present invention, as defined by the appended claims.

Claim 1:
A vibration actuator (<NUM>), comprising:
a fixing body (<NUM>) including a magnet (<NUM>, <NUM>);
a movable body (<NUM>) including a coil holder (<NUM>), a coil (<NUM>) and a weight (<NUM>), and configured to reciprocally move in a vibration direction with respect to the fixing body (<NUM>) by cooperation work of the coil (<NUM>) that is to be energized and the magnet (<NUM>, <NUM>); and
an elastic body (<NUM>) movably supporting the movable body (<NUM>) with respect to the fixing body (<NUM>), characterized in that
the coil holder (<NUM>) has the coil (<NUM>) disposed on an inner side of the coil holder (<NUM>), and holds an outer periphery face of the coil (<NUM>),
the elastic body (<NUM>) is fixed at one side face of the coil holder (<NUM>), and the weight (<NUM>) is fixed at the other side face of the coil holder (<NUM>) on the opposite side of the elastic body (<NUM>),
the coil (<NUM>) and the magnet (<NUM>, <NUM>) are provided on the fixing body (<NUM>) and the movable body (<NUM>) such that the magnet (<NUM>, <NUM>) is capable of being inserted into and removed from the coil (<NUM>) in the vibration direction,
the elastic body (<NUM>) is a plate-like elastic body with one end being fixed to the fixing body (<NUM>) and another end being fixed to the coil holder (<NUM>) to support the movable body (<NUM>) with a cantilever structure to be capable of reciprocally oscillating in the vibration direction, and
one end of the weight (<NUM>) is a free end and another end of the weight (<NUM>) is fixed to the coil holder (<NUM>).