KR20170057977A

KR20170057977A - Piezo Actuator

Info

Publication number: KR20170057977A
Application number: KR1020150161549A
Authority: KR
Inventors: 이인호
Original assignee: 이인호
Priority date: 2015-11-18
Filing date: 2015-11-18
Publication date: 2017-05-26

Abstract

According to the present invention, there is provided a piezoelectric actuator comprising: a fixed portion for providing an internal space of a predetermined size; a piezo disposed in an internal space of the fixed portion and contracted and expanded by an applied voltage; A weight which is coupled to one end of the diaphragm and vibrates due to the vibration of the diaphragm, and a weight which vibrates by the vibration of the diaphragm and a direction of movement of the weight, And at least a part of the weight is arranged to face the fixing member in the direction of movement of the weight. The piezoelectric actuator maximizes the vibration force in a very small space, minimizes the consumed current and minimizes the electromagnetic noise Piezoelectric actuator that can reduce damage caused by external impact such as dropping Data.

Description

Piezo Actuator

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a piezo actuator, and more particularly, to a piezo actuator mounted on a wearable device, a personal portable terminal, a tablet PC, a game machine, or a remote controller and designed to vibrate.

In general, one of the functions necessary for a communication device is a receiving function. This incoming function has the function of notifying by sound or vibration.

The vibration function is mainly used when the melody or bell is transmitted to the outside through the speaker to prevent damage to the other person. For this vibration, a small actuator is driven so that the driving force is transmitted to the case of the device So that the device can vibrate.

In recent years, as the spread of smart phones and tablets equipped with a touch screen is increasing, a vibration function has been required to provide a virtual touch feeling to a user beyond a simple incoming call function.

In order to realize the function of providing the virtual touch feeling to the user by using the vibration, the piezo actuator having quick response and high vibration performance is used.

In addition, the market for wearable devices that are linked with smartphones is exploding, as the popularity of smart phones has become more active. A wearable device is a device that wears on a wearer's body such as a glasses, a watch, a necklace, etc., and the size of the wearable device is small, so that the component parts thereof must be downsized. Therefore, the need for a high performance compact vibrator is emphasized.

In addition, a wearable device that is always worn and carried is required to have a structure in which a shock such as a bump or drop often occurs, so that the adopted part is not damaged by an external impact.

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above problems of the prior art, and it is an object of the present invention to provide a piezoelectric actuator that maximizes a vibration force in a very small space, minimizes consumed current and minimizes electromagnetic noise, There is a purpose to improve defectiveness.

In order to accomplish this object, there is provided a piezoelectric actuator comprising: a fixed portion for providing an internal space of a predetermined size; a piezo disposed in an internal space of the fixed portion and contracted and expanded by an applied voltage; A weight which vibrates due to the vibration of the diaphragm, and a weight which is connected to one end of the diaphragm and which vibrates by the vibration of the diaphragm, And a stopper formed in the direction of motion

At least a part of the weight in the direction of movement of the weight can be arranged facing the fixing member.

The stopper may be integrally formed with the weight. The stopper may be formed separately from the weight. The stopper may be integrally formed with the fixing portion. The stopper may be formed separately from the fixing portion and coupled.

And a stopper may be provided between the weight and the fixing member. And the stopper is integrally formed with the fixing member.

And a piezoelectric fixing jaw which surrounds a part of the piezoelectric film may be provided on a part of the diaphragm. The piezo-electric fixing jaw may be integrally formed with the diaphragm. Further, the piezoelectric fixing jaw may be formed in a separate piezoelectric fixing member, and the piezoelectric fixing member and the diaphragm may be combined to form an integral body.

The features and advantages of the present invention will become apparent from the following detailed description based on the accompanying drawings. Prior to this, terms and words used in the present specification and claims should be construed in accordance with the spirit and scope of the present invention, on the basis of the principle that a concept of a term can be properly defined to explain it in a normal and best manner. .

According to the present invention, there is provided a piezo actuator capable of maximizing a vibration force in a very small space, minimizing an electric current consumed, minimizing electromagnetic noise, and reducing damage caused by external impact such as dropping.

1 is a cross-sectional view of a piezo actuator according to the present invention;
2 is an exploded perspective view of the piezo actuator according to the present invention.
Fig. 3 is a plan view of a stopper provided in the piezo actuator according to the present invention.
4 Another embodiment of the piezo actuator according to the present invention
5 is a view showing another embodiment of the piezo actuator according to the present invention.
Fig. 6 shows another embodiment of the piezo actuator according to the present invention.
7 is a perspective view of a piezoelectric actuator according to an embodiment of the present invention.
Fig. 8 shows the principle of operation of the piezo actuator according to the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a cross-sectional view of a piezo actuator 100 according to an embodiment of the present invention, and FIG. 2 is an exploded perspective view of a piezo actuator 100 shown in FIG.

As shown in the drawing, the piezo actuator 100 of the present invention includes a fixing part 110 for providing an internal space of a predetermined size, a piezoelectric actuator 110 disposed in the internal space of the fixing part 110, A diaphragm 130 coupled with the piezo 140 and vibrating due to contraction and expansion of the piezo 140, a fixing member 150 coupling the diaphragm 130 and the fixing portion 110, A weight 120 coupled to one end of the diaphragm 130 and vibrated by the vibration of the diaphragm 130 and a weight member 120 disposed between the weight 120 and the fixing unit 110, And a stopper 160 formed in a predetermined direction.

When the power is supplied from the outside through the power supply unit 170, the piezo 140 has a characteristic of contracting or expanding according to a direction in which the voltage is applied. The diaphragm 130 is coupled to one side surface of the piezo 140 and is bent upward or downward according to contraction or expansion of the piezo 140 to generate vibration. The piezo 140 may be coupled to the lower surface of the diaphragm 130 or may be coupled to the upper surface of the diaphragm 130 as shown in FIG. In addition, a plurality of the piezos 140 may be formed and coupled to the upper and lower sides of the diaphragm 130 to increase the force generated from the piezo 140.

The diaphragm 130 is coupled with the piezo 140 so that the diaphragm 130 is flexed repeatedly and flexibly due to shrinkage and expansion of the piezo 140 to generate vibration. Is preferably made of a metal material. Bonding when the piezo 140 and the diaphragm 130 are coupled to each other, or the like.

One end of the diaphragm 130 is fixed to a part of the fixing portion 110 so that vibrations generated from the piezo 140 and the diaphragm 130 can be transmitted to the outside through the fixing portion 110, The diaphragm 130 may include a fixing member 150 for coupling the diaphragm 130 to the fixing unit 110 so that the diaphragm 130 and the fixing member 150 or the fixing member 150 and the fixing unit 150 110 may be joined by welding, bonding or caulking. The fixing member 150 may be integrally formed with the fixing portion 110 or the diaphragm 130 to reduce the number of components of the piezoelectric actuator 100 and to simplify the manufacturing process.

The weight 120 is fixed to one end of the diaphragm 130 to amplify vibrations generated by the piezo 140 and the diaphragm 130. In order to maximize the weight of the weight 120, it is preferable to use a metal having a high specific gravity such as tungsten. In addition to tungsten, the weight 120 may be made of a material having a high specific gravity, And is not particularly limited.

The weight 120 may be joined to the diaphragm 130 by welding, bonding or caulking. A method of fixing the weight 120 and the diaphragm 130 is not particularly limited but the weight 120 may be fixed to a part of the diaphragm 130 or a part of the weight 120 A weight fixing protrusion may be provided to enclose the weight 120 so that the area of engagement with the weight 120 is increased to increase the coupling strength.

It is preferable that the weight 120 is formed to extend from the coupling portion with the diaphragm 130 in the direction of the fixing member 150 in order to maximize the weight of the weight 120. By increasing the weight of the weight 120, the vibration power is maximized. At this time, when the end of the weight 120 is positioned on the diaphragm 130, when the impact occurs from the outside such as collision or drop, the weight 120 impacts the diaphragm 130 to give an impact, Deformation of the diaphragm 130 or breakage of the piezo 140 coupled with the diaphragm 130 may occur. However, when the end of the weight 120 is formed to be long to the upper portion of the fixing member 150, the end of the weight 120 is stopped by the fixing member 150 which is firm and unbroken The weight 120 does not hit the diaphragm 130 and the diaphragm 130 and the piezo 140 can be prevented from being deformed or damaged.

The fixing part 110 fixes internal components and protects the product from external shocks and foreign objects and transmits the vibration generated from the piezo 140 and the diaphragm 130 to the outside. The fixing part 110 may be integrally formed, but may be formed as a plurality of parts for integrally combining the parts. Also, in the embodiment shown in the drawings, the piezo actuator 100 has a rectangular parallelepiped shape. However, the piezo actuator 100 may have various shapes according to the mounting method and the like.

And a power supply unit 150 having one end electrically connected to the piezo 140 and the other end exposed to the outside of the fixing unit 110 so that an electric signal supplied from the outside can be supplied to the piezo 140. [ (170). The power supply unit 170 may be formed of a flexible circuit board to mitigate vibrational shock transmitted to the power supply unit 170 when the piezo 140 vibrates. In addition, the power supply unit 170 is not limited to a constituent material such as a printed circuit board or a metal plate if an external power source can be connected to the piezo 140.

The damping member 180 is disposed between the fixed portion 110 and the weight 120 so that the fixed portion 110 and the weight 120 are fixed to each other when the weight 120 is lifted up or down. It is possible to prevent an impact caused by collision to prevent noise, and it is possible to prevent the internal parts of the piezoelectric actuator 100 from colliding with each other due to the impact to be damaged or deformed. In some cases, the damping member 180 may be used to limit the driving displacement of the weight 120 to adjust the vibration force of the piezoelectric actuator 100. [ The damping member 180 is preferably made of a soft material such as silicone, rubber, or urethane so as to absorb the impact.

The damping member 180 may be provided between the weight 120 and the diaphragm 130 or between the weight 120 and the fixing unit 110 or between the piezo 140 and the fixing unit 110. [ Thereby maximizing the effect of preventing the piezoelectric actuator 100 from being damaged or deformed due to collision between components during operation of the piezoelectric actuator 100 or from the outside.

The displacement is limited by the damping member 180 disposed at a position where the weight 120 is in contact with the fixed portion 110. [ The damping member 180 may be formed of a soft material such as silicone, urethane, rubber, or the like, so that the damping member 180 may absorb noise when contacting the weight 120, thereby reducing noise. However, when a large force is applied due to an external impact or the like, the damping member 180 of a soft material is compressed to excessively move the weight 120. When the piezo 140 is damaged by contact with the fixing portion 110, The diaphragm 130 may be deformed due to movement. The weight 120 is provided with a stopper 160 to allow the weight 120 to contact the damping member 180 when the piezoelectric actuator 100 operates normally and the stopper 160 The stopper 160 does not affect the driving because the stopper 160 does not contact the fixing part 110. However, when a large impact is applied from the outside, the stopper 160 contacts the fixing part 110, The diaphragm 140 and the diaphragm 130 are prevented from being damaged or deformed.

The stopper 160 may be integrally formed with the weight 120 by sintering or injection molding. The stopper 160 may be separately formed using a metal, a resin, or a material including a rubber component, and may be formed integrally with the weight 120 by bonding, welding, caulking or the like. When the weight 120 is made of tungsten, the stopper 160 may be formed of a material including a metal, a resin, or a rubber component. Alternatively, the stopper 160 may be bonded, welded, Or may be formed by bonding by a method such as caulking. The stopper 160 may be formed integrally with the fixing portion 110 by processing a part of the fixing portion 110 to simplify the assembling process.

A stopper 160 is provided between the weight 120 and the fixing member 150 so that the weight 120 does not strike a thin portion of the diaphragm 130 to cause deformation of the diaphragm 130 And the impact is transmitted through the diaphragm 130, thereby preventing the piezo 140 from being damaged. Since the shock is not applied to the thin portion where the vibration plate 130 is likely to be deformed by the contact with the stopper 160 disposed on the upper surface of the fixing member 150 having the end portion of the weight 120 tightly fixed, The diaphragm 130 or the piezo 140 can be prevented from being damaged. If the stopper 160 is not provided, a part of the weight 120 may directly collide with the diaphragm 130, causing the diaphragm 130 to be struck or bent.

The stopper 160 may be integrally formed with the weight 120 or the fixing member 150 or separately formed of a metal, resin, or rubber, and may be formed by bonding, welding, caulking, 120 or between the weight 120 and the fixing member 150 in combination with the fixing member 150 or the vibration plate 130. The stopper 160 may be integrally formed with the weight 120 or may be formed as a separate part so as to be disposed between the fixing member 150 and the fixing part 110 in combination with the weight 120 have. The stopper 160 may be disposed between the fixing member 150 and the fixing unit 110 by being coupled to the fixing member 150 or the fixing unit 110. The stopper 160 may be integrally formed with the fixing portion 110 or the fixing member 150.

If the piezo-electric fixing jaw 190 is provided on a part of the diaphragm 130 to enclose a part of the piezo 140, the piezo-electric actuator 140 is strongly supported to the side surface to prevent separation of the piezo 140 due to external force And the breakage of the piezo 140 can be prevented. The piezoelectric fixing jaw 190 may be formed integrally with the diaphragm 130 or may be formed integrally with the diaphragm 130 by being formed on a separate piezoelectric fixing member 200.

3 is a view for explaining the stopper 160 provided in the piezoelectric actuator 100 according to the present invention. The piezoelectric 140 is shrunk or expanded when power is supplied to the piezoelectric 140 through the power supply unit 170 and one side of the piezoelectric 140 is coupled to the diaphragm 130, The diaphragm 130 is bent concavely or convexly in accordance with the contraction or expansion of the diaphragm 130 and the weight 120 coupled to one end of the diaphragm 130 moves up or down. The displacement is limited by the damping member 180 disposed at a position where the weight 120 is in contact with the fixed portion 110. [ The damping member 180 may be formed of a soft material such as silicone, urethane, rubber, or the like, so that the damping member 180 may absorb noise when contacting the weight 120, thereby reducing noise. However, when a large force is applied due to an external impact or the like, the damping member 180 of a soft material is compressed and the weight 120 moves excessively as shown in FIG. 3 (c) The diaphragm 130 may be deformed due to breakage or excessive movement in contact with the portion 110. A stopper 160 is provided on the weight 120 to prevent the weight 120 from moving to the damping member 180 when the piezo actuator 100 operates normally, The stopper 160 is not in contact with the fixing portion 110 so that the stopper 160 does not affect the driving. However, when a large impact is applied from the outside, as shown in FIG. 3 (b) The stopper 160 comes into contact with the fixing portion 110 to prevent the weight 120 from being excessively moved to prevent breakage or deformation of the piezo 140 and the diaphragm 130. [

The stopper 160 may be integrally formed with the weight 120 by sintering or injection molding.

4 shows another embodiment of the stopper 160 provided in the piezoelectric actuator 100 according to the present invention. As shown in FIG. 4A, the stopper 160 may be separately provided using a metal, a resin, or a material including a rubber component so that the stopper 160 may be bonded to the weight 120, Or may be integrally bonded and formed. 4 (b), when the weight 120 is made of a tungsten material, the stopper 160 is separately provided using a material including a metal, a resin, or a rubber component, Or may be coupled with the fixing portion 110 by bonding, welding, caulking or the like. As shown in FIG. 4 (c), the stopper 160 may be formed integrally with the fixing part 110 by processing a part of the fixing part 110, thereby simplifying the assembling process.

5 shows another embodiment of the stopper 160 provided in the piezo actuator 100 according to the present invention. A stopper 160 is provided between the weight 120 and the fixing member 150 so that the weight 120 does not strike a thin portion of the diaphragm 130, It is possible to prevent the deformation from occurring and to prevent the piezoelectric 140 from being damaged due to the impact transmitted through the vibration plate 130.

As shown in FIG. 5 (b), the diaphragm 130 is deformed by the contact with the stopper 160 disposed on the upper surface of the fixing member 150 having the end of the weight 120 tightly fixed An impact is not applied to an easy thin portion so that the diaphragm 130 or the piezo 140 can be prevented from being damaged. 5C, when the stopper 160 is not provided, a part of the weight 120 may directly collide with the diaphragm 130, and the diaphragm 130 may be struck or bent .

The stopper 160 may be integrally formed with the weight 120 or the fixing member 150 or separately formed of a metal, resin, or rubber, and may be formed by bonding, welding, caulking, 120 or between the weight 120 and the fixing member 150 in combination with the fixing member 150 or the vibration plate 130.

6 shows another embodiment of the stopper 160 provided in the piezo actuator 100 according to the present invention. 6 (a), the stopper 160 may be formed integrally with the weight 120 or may be formed as a separate component, and may be coupled with the weight 120 to form the stopper 160, (110). &Lt; / RTI > 6 (b), the stopper 160 is coupled to the fixing member 150 or the fixing unit 110 to be disposed between the fixing member 150 and the fixing unit 110 . The stopper 160 may be integrally formed with the fixing portion 110 or the fixing member 150.

7 is a view for explaining the piezo-electric fixing jaw 190. Fig. 7A shows the coupling between the diaphragm 130 and the piezo 140 without the piezo-fixing jaw 190. As shown in FIG. 7A, one side of the piezo 140 and the diaphragm 130 ) Using only one side. By bonding only the surfaces facing each other as described above, bonding can be separated from the end where the piezoelectric actuator 140 is attached when the piezoelectric actuator 100 is driven or when an external shock is applied. When the piezo 140 and the diaphragm 130 are separated from each other, power of the piezo 140 can not be normally transmitted to the diaphragm 130 due to shrinkage or expansion of the diaphragm 130. As a result, If it is different, defects such as a change in resonance frequency may occur. As shown in FIGS. 7 (b) to 7 (c), a piezo-electric fixing jaw 190 may be formed on the side surface of the piezo 140 to strengthen the bonding of the piezo 140, thereby enhancing durability. The resonance frequency can be lowered by forming the piezo-electric fixing jaw 190 to be narrow and flexible so that the resonance frequency can be lowered and the protection can be maximized by forming the piezoelectric fixing jaw 190 to be wide. 7 (d), the piezoelectric fixing member 190 may be formed by coupling a separate piezoelectric fixing member 200 having the piezoelectric fixing jaw 190 with the vibration plate 130 .

8 is a view for explaining the operation of the piezo actuator 100 according to the present invention.

When the AC power is supplied to the piezo 140 through the power supply unit 170, the piezo 140 shrinks or expands according to the direction of the applied voltage, and the diaphragm 130 The diaphragm 130 is repeatedly bent in a concave or convex manner by the contraction or expansion of the piezo 140 and the weight 120 coupled to the diaphragm 130 moves and vibrates upward or downward .

While the invention has been shown and described with reference to certain embodiments thereof, it will be understood by those skilled in the art that various changes and modifications may be made therein without departing from the spirit and scope of the invention .

100: Piezo actuator 110:
120: weight 130: diaphragm
140: Piezo 150: Fixing member
160: Stopper 170: Power supply
180: damping member 190:
200: a piezo fixing member

Claims

A fixing part for providing an internal space of a predetermined size;
A piezo disposed in an inner space of the fixed portion and contracted and expanded by an applied voltage;
A diaphragm coupled with the piezo and vibrating due to contraction and expansion of the piezo;
A fixing member for coupling the vibration plate and the fixing portion;
A weight coupled to one end of the diaphragm and vibrated by the vibration of the diaphragm; And
And a stopper formed between the weight and the fixed portion in the direction of movement of the weight,

The method according to claim 1,
Characterized in that at least a part of the weight is arranged to face the fixing member in the direction of movement of the weight

The method according to claim 1,
Characterized in that the stopper is integrally formed with the weight.

The method according to claim 1,
Characterized in that the stopper is separately formed and joined to the weight.

The method according to claim 1,
Characterized in that the stopper is integrally formed with the fixed portion.

The method according to claim 1,
Characterized in that the stopper is formed separately from the fixed portion and is engaged with the fixed portion.

The method according to claim 1,
And a stopper is provided between the weight and the fixing member.

The method according to claim 1,
Characterized in that the stopper is integrally formed with the fixing member.

The method according to claim 1,
And a piezo-electric fixing jaw which surrounds a part of the piezo at a part of the diaphragm.

10. The method of claim 9,
And the piezo-electric fixing jaw is integrally formed with the diaphragm.

10. The method of claim 9,
Characterized in that the piezoelectric fixing jaw is formed in a separate piezoelectric fixing member, and the piezoelectric fixing member and the diaphragm are combined to form a single unit.