JPH07178370A - Vibrator and vibrating actuator - Google Patents

Abstract

PURPOSE:To obtain a vibrator, etc., having high general applicability which is small in size and flat in shape an is applied to any of a rotary type and a linear type and from which driving force is taken out in any direction and also large driving force is taken out. CONSTITUTION:An elastic body 3 having a space part 2 in the central part and having the shape of a flat quadrangle is installed. Piezoelectric bodies 4 are stuck to the four sides of the elastic body 3. By applying voltage to the piezoelectric bodies 4, strains is generated in the piezoelectric bodies 4 to allow the generation of prescribed vibration in the elastic body 3. By rotating a vibration mode at this time, elliptical vibration is generated in corner parts 3 an central parts of sides 3a of the elastic body 3. Such a vibrator, etc., are used for various kinds of vibrating actuators, and the whole device is formed in small size and flat. Since they have high strength, large driving force is obtained. Therefore, they have high general applicability as a driving source.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibrator using a piezoelectric element and a vibration actuator using the vibrator.

[0002]

2. Description of the Related Art In recent years, a vibration actuator using a vibrator using a piezoelectric element has been put into practical use, and its use as a drive source of a movable part in devices such as a copying machine, a printer and a facsimile is under study.

As a first conventional example of such a vibration actuator, there is a "rotational drive device utilizing ultrasonic vibration" disclosed in Japanese Patent Publication No. 59-37672. This is because a magnetostrictive vibrator is used as an ultrasonic vibrator that generates ultrasonic vibration, and a high-frequency voltage is applied to the coil to cause the ultrasonic vibrator to expand and contract due to the magnetic field. By vibrating the diaphragm attached to the child in the vertical direction, an elliptical vibration is generated at the tip of the diaphragm. Then, the vibrating plate of the rotating shaft is brought into contact with the tip of the elliptical vibrating plate, and the rotating shaft is rotated by the frictional force between the vibrating plate of the ultrasonic transducer and the vibrating plate of the rotating shaft.

Next, as a second conventional example of the vibration actuator, there is a "motor device utilizing ultrasonic vibration" disclosed in Japanese Patent Application Laid-Open No. 58-148682. This is because two electrostrictive elements (or magnetostrictive elements) are built in a cylindrical bending oscillator, and high-frequency voltages with different phases are applied to the electrodes in contact with these two electrostrictive elements to apply the entire bending oscillator. Rotating circular vibration is generated by bending vibration that is a combination of longitudinal vibration and lateral vibration. Then, the rotor is brought into contact with the bending oscillator that vibrates in a circular rotation, and the rotor is rotated by the frictional force between the bending oscillator and the rotor.

Further, as a third conventional example of the vibration actuator, there is a "thin linear motor using a bent double mode piezoelectric ceramic square plate", which was published in a collection of lectures of the Acoustical Society in March 1993 ( March 1993, Proceedings of the Acoustical Society of Japan P.857 Yoshiro Tomikawa, Akira Yabuki, Shunji Ogasawara, Takehiro Takano). The oscillator presented in this paper utilizes the in-plane vibration of piezoelectric ceramics formed in the shape of a hollow square frame, and drives the piezoelectric ceramics in two phases to generate elliptical vibrations at the corners and sides. It is a structure that allows it. Then, in this paper, an optical pickup element is held in the central hollow portion of a piezoelectric ceramic that becomes a vibrator, and such a vibrator is slidably held by a pair of rails and It is assumed that the oscillator constitutes a linear motor that runs on a rail.

[0006]

However, in the first conventional example, since the rotation direction of the rotary shaft is determined by the inclination direction of the vibrating piece that contacts the diaphragm of the ultrasonic transducer, the driving force that can be taken out is reduced. There is a problem that the direction is limited and it is difficult to use as a general-purpose drive source. In addition, the vibrating piece of the rotating body has a thin tip portion, and the friction between the vibrating piece and the vibration plate of the ultrasonic vibrator causes severe wear, resulting in a short life.

Further, in the second conventional example, while the rotor can be rotated in both forward and reverse directions, in order to configure it as a linear motor, it is necessary to take measures to circulate a traveling wave, which causes energy loss. There is a problem that it is too large and not suitable for practical use.

In the third conventional example, since the whole vibrator is made of piezoelectric ceramic having low strength, a large load cannot be applied to the vibrator and a large driving force cannot be obtained. It has the drawback.

INDUSTRIAL APPLICABILITY The present invention has a small and flat shape, can be applied to both rotary type and linear type, can take out driving force in any direction, and can take out large driving force. It is an object of the present invention to obtain a vibrator and a vibration actuator having high versatility so that

[0010]

The inventions described in claims 1 to 7 are inventions of vibrators, and the inventions described in claims 8 to 12 utilize the vibrators. It is an invention of a vibration actuator.

A vibrator according to a first aspect of the present invention includes a flat quadrangular elastic body having a space at the center and piezoelectric bodies fixed to the four sides of the elastic body.

According to a second aspect of the invention, in the vibrator according to the first aspect, a recess is formed in a portion of the elastic body to which the piezoelectric body is fixed, and the piezoelectric body is more piezoelectric than a surface including each side of the elastic body. The position is set so that the body does not protrude.

A vibrator according to a third aspect of the present invention is the vibrator according to the first or second aspect, wherein the space portion has a great circle centered at an intersection of two diagonal lines of the elastic body and the great circle. And small circles respectively arranged at symmetrical positions in the vicinity of the four corners of the elastic body communicating with.

A vibrator according to a fourth aspect of the present invention is the vibrator according to the first, second or third aspect, wherein at least one piezoelectric body is divided into two in a direction orthogonal to a longitudinal direction of a side of the elastic body. There is.

A vibrator according to a fifth aspect of the present invention is the vibrator according to the first, second or third aspects, wherein both ends of each piezoelectric body are divided in the longitudinal direction of the sides of the elastic body.

A vibrator according to a sixth aspect of the invention is the vibrator according to the first, second or third aspects, wherein each piezoelectric body has a shape in which both ends thereof are removed.

A vibrator according to a seventh aspect of the invention is the vibrator according to the first, second, third, fourth, fifth or sixth aspect, in which each side of the elastic body is generated by applying a voltage to the piezoelectric body. The driving unit may further include a driving unit that causes elliptical vibration at a corner portion of the elastic side or a central portion of the side by using the bending.

According to an eighth aspect of the present invention, there is provided a vibration actuator in which the vibrator according to the first, second or third aspect of the present invention and a movable body which is in pressure contact with at least one corner portion or at least one side center portion of the vibrator. Including and

A vibration actuator according to a ninth aspect of the present invention is the vibration actuator according to the eighth aspect.
The moving body is pressed against the vibrator in the orthogonal direction, and the pressure contact portion between the vibrator and the moving body is formed on the tapered surface.

According to a tenth aspect of the invention, there is provided a vibration actuator comprising: the vibrator according to the second aspect or the vibrator according to the second and third aspects; a rail; and pressure contact means for pressing one side of the vibrator against the rail. including.

A vibration actuator according to an invention of claim 11 is a vibrator according to claim 1, 2 or 3, a pair of rails slidably holding the vibrator, and rails of an elastic body in the vibrator. The projection includes a projection formed to project from the central portion of the parallel sides, and a restriction surface formed on a rail that restricts movement of the projection and the corner of the elastic body in a direction orthogonal to the sliding direction of the vibrator.

A vibration actuator according to a twelfth aspect of the present invention is a vibrator according to the third aspect, a vibrator-side screw portion formed around a great circle forming a space portion of the vibrator, and the vibration. And a moving body having a moving body side screw portion that is screwed into the child side screw portion.

[0023]

According to the first aspect of the invention, when a voltage is applied to the piezoelectric body, the piezoelectric body is distorted and each side of the elastic body is curved. Therefore, when the piezoelectric body is driven by the drive unit according to the seventh aspect of the invention, elliptical vibration is generated at the corners and the center of the sides of the piezoelectric body, and it is easy to switch the direction of the elliptical vibration. Therefore, it can be applied to various types of vibration actuators. Moreover, the whole is formed in a small and flat shape, and is highly versatile as a drive source. Further, since the piezoelectric body having a low strength is fixed to the elastic body, the strength is high and a large driving force can be obtained as compared with the vibrator in which the entire body is composed of the piezoelectric body.

According to the second aspect of the present invention, since the piezoelectric body is retracted more than each side of the elastic body, it is possible to form a vibration actuator in which a vibrator is directly pressed against a planar object. Therefore, versatility as a drive source is further enhanced. Moreover, the elliptical vibrations generated at these four corners are further magnified, and a larger driving force is obtained at such corners.

According to the third aspect of the invention, the space portion of the elastic body is formed only by punching the elastic body, so that the manufacturing process can be simplified.

According to the fourth aspect of the present invention, the vibration generated in the vibrator is detected by extracting the voltage generated in one of the two divided piezoelectric bodies and examining the value.

According to the fifth and sixth aspects of the present invention, the elastic body of the vibrator to be grounded and the piezoelectric body are separated from each other, so that a short circuit or discharge to the elastic body is prevented.

According to the seventh aspect of the invention, when a voltage is applied to the piezoelectric body from the drive section, each side of the elastic body bends. Then, by setting the direction in which such bending occurs in a predetermined direction, elliptical vibration occurs at the corners and the center of the sides of the elastic body. At this time, since the bending mode of the elastic body is used, the amplitude of the elliptical vibration becomes large.

According to the eighth aspect of the present invention, elliptical vibration is generated in the portion of the elastic body against which the moving body is in pressure contact, and power is transmitted to the moving body. As a result, the moving body makes a rotational movement or a linear movement.

According to the ninth aspect of the invention, the contact area between the elastic body and the moving body is widened, and a large driving force can be obtained. Further, since the moving body is pressed against the vibrator in the orthogonal direction, the whole is formed flatter.

According to the tenth aspect of the present invention, when elliptical vibration occurs in a corner portion of the vibrator that is pressed against the rail of the elastic body, the vibrator self-propels on the rail.

According to the eleventh aspect of the present invention, by bending the elastic body of the vibrator on two sides parallel to the rails in the same direction, the protrusion formed on the one rail to project from the elastic body is a regulation surface. When the rail is regulated and abutted on the other rail, the corner portion of the elastic body is regulated and abutted on the regulation surface on the other rail, so that the elliptical vibration generated at the corner portion of the elastic body and the central portion of the side of the elastic body are positioned. The elliptical vibration generated in the protruding portion acts as a driving force, and the vibrator self-propels on the rail.

According to the twelfth aspect of the present invention, in the elastic body of the vibrator, elliptical vibration is generated in the vibrator-side screw portion, and this elliptical vibration causes rotational movement in the moving body-side screw portion of the moving body. As a result, the moving body moves in the axial direction while rotating.

[0034]

【Example】

[First Embodiment] As a first embodiment of the present invention, an example of a vibrator according to claims 1 and 7 will be described with reference to FIGS. 1 and 2, and a rotary vibration using the vibrator. An example of the actuator will be described with reference to FIGS. This vibration actuator corresponds to the invention described in claims 8 and 9.

<Vibrator> First, as shown in FIG. 1, the oscillator 1 of the present embodiment has a flat quadrangular elastic body 3 having a space 2 at the center and four elastic bodies 3. The piezoelectric body 4 is fixed to the side 3a. here,
The space 2 has a quadrangular shape, and thus the elastic body 3 is formed in a frame shape. The piezoelectric body 4 is a thin rectangular piezoelectric element, and the elastic body 3
Is adhered to the outer surface of each side 3a. In FIG. 1, the polarization direction of such a piezoelectric body 4 is indicated by a white arrow.

Next, a drive unit 5 is connected to the piezoelectric body 4. The drive unit 5 includes the elastic body 3 facing each other.
Of the A-phase and B-phase piezoelectric bodies 4 having the same set of the piezoelectric bodies 4 adhered to the two sides 3a of the above, respectively, a voltage is applied from an AC power supply 6 respectively. . In the drive unit 5 as described above, the elastic body 3 is grounded.

FIG. 2 exemplifies the vibration mode of the vibrator 1 generated by the driving of the driving unit 5 in such a structure.
First, in FIGS. 2A and 2C, in one vibration mode when a voltage is applied from the drive unit 5 to the piezoelectric body 4 of either the A phase or the B phase, the frequency of the applied voltage is shifted by a half cycle. 3 illustrates an example of a deformed state of the vibrator 1 when being applied. Also,
2 (b) and 2 (d), the frequency of the applied voltage shifts by a half cycle in another vibration mode when a voltage is applied to the piezoelectric body 4 of the other phase at the same resonance frequency as in FIGS. 2 (a) and 2 (c). Oscillator 1
3 is an example of the deformed state of each of the sides 3a of the vibrator 1.
Has the same isomorphic degeneracy as in FIGS. 2 (a) and 2 (c). Therefore, when the two vibration modes that are degenerate in the same shape as described above are excited by being displaced by ¼ cycle in time, the vibration modes rotate. In other words, the oscillator 1 is shown in FIG.
The vibration modes rotate in the order of (c) and (d), and resonance vibration occurs. At this time, when the vibration is excited with a shift of 1/4 cycle, the oscillator 1 is shown in FIG. 2 (a) (d) (c) (b) every quarter cycle.
The vibration modes rotate in this order, and resonance vibration occurs. More specifically, the resonant frequency the amplitude of the voltage as V ₀ and f _0, a piezoelectric element 4 of the A-phase exciting at V ₀ cos2πf ₀ t, the piezoelectric elements 4 of B-phase V ₀ cos (2πf ₀ t- When excited with π / 2) = V ₀ sin2πf ₀ t, the vibration modes rotate in the order of FIGS. 2 (a) (d) (c) (b), and the A-phase piezoelectric body 4 with V ₀ cos 2πf ₀ t When excited and the B-phase piezoelectric body 4 is excited with V ₀ cos (2πf ₀ t + π / 2) = − V ₀ sin2πf ₀ t, the vibration modes in the order of FIG. 2 (a) (d) (c) (b) Rotates. Here, as illustrated in FIG.
When resonance vibration occurs in the order of Fig.2 (a) (b) (c) (d),
On each side 3a and each corner 3b of the elastic body 3 in the vibrator 1, elliptical vibration as shown by a solid arrow in FIG. 2A is generated. When resonance vibration occurs in the vibrator 1 in the order of FIGS. 2 (a) (d) (c) (b), each side 3a and each corner 3 of the elastic body 3 is generated.
An elliptic vibration is generated at point b, as shown by the dotted arrow in FIG.

Therefore, the elliptical vibration generated in each side 3a and each corner 3b of the elastic body 3 in the vibrator 1 is utilized to drive the driven object in the vibrator 1 in this embodiment. It is the operating principle. Therefore, it is easy to use for various types of actuators, and the vibrator 1 having high versatility can be obtained. Further, since the whole is formed in a small size and has a flat shape, it can be installed in any place, and from this point, it is highly versatile as a drive source. Furthermore, since the piezoelectric body 4 having a low strength is bonded to the elastic body 3, the piezoelectric body 4 has a higher strength and a larger driving force than that of a vibrator which is entirely composed of the piezoelectric body.

<Rotary Vibration Actuator as Application Example of Vibrator> Next, the oscillator 1 illustrated in FIGS.
An example of the rotary type vibration actuator utilizing the is shown in FIGS. In this vibration actuator 7, a vibrator 10 as a stator and a rotor 11 as a moving body driven by the vibrator 1 are housed in a case 10 formed by a plate-shaped substrate 8 and a cover 9. It is a structure.

That is, the vibrator 1 is fixed to the substrate 8 via the cushioning material 12a made of rubber or the like, and the cover 9 is fixed to the substrate 8 by the screw 13 in this state. . The vibrator 1 is also provided on the cover 9.
A cushioning material 12b made of a rubber material or the like is provided between and. The shaft 11 a of the rotor 11 is rotatably attached to the substrate 8 and the cover 9 via a bearing 14. Here, this rotor 11
Is arranged in the space 2 of the vibrator 1 and is in contact with the vibrator 1 in the orthogonal direction. A stator taper surface 15 as a taper surface is formed on the vibrator 1 so as to be positioned at the contact portion, and the rotor 11
A mover taper surface 16 as a taper surface is formed on the. The stator tapered surface 15 is formed at the center of each side 3a of the elastic body 3 of the vibrator 1. The shape of the vibrator 1 as described above is shown in FIGS. 4 (a) and 4 (b), and the shape of the rotor 11 is shown in FIGS. 5 (a) and 5 (b). The cover 9 is provided with a leaf spring 17 for pressing the mover taper surface 16 of the rotor 11 against the stator taper surface 15 of the vibrator 1. Although not shown,
The buffer material 12b is cut with a groove for passing a wiring to the piezoelectric body 4.

In such a structure, when the driving portion 5 drives the piezoelectric body 4 to generate elliptical vibration as illustrated in FIG. 2 in the central portion of each side 3a of the vibrator 1, this vibration generating portion is generated. The rotor 11 in pressure contact rotates. This allows
The driving force can be taken out from the shaft 11a of the rotor 11. At this time, it is possible to rotate the rotor 11 in both forward and reverse directions by switching the direction of elliptical vibration. Further, since the vibrator 1 and the rotor 11 are in pressure contact with each other via the stator taper surface 15 and the mover taper surface 16, the contact area is wide and the durability is excellent and a strong driving force can be obtained. Further, since the rotor 11 is arranged in the space 2 of the vibrator 1 and is in contact with the vibrator 1 in the orthogonal direction, the overall shape of the vibration actuator 7 is flattened, and the vibration actuator 7 having an extremely small thickness can be obtained. Further, similar to a general vibration motor, it has a characteristic that a large torque can be obtained at a low rotation speed and the rotor 11 can be held to prevent its free rotation when driven.

[Second Embodiment] As a second embodiment of the present invention, an example of a vibrator according to claims 2 and 7 will be described with reference to FIGS. 6 and 7, and a vibrator using the vibrator will be described. An example of a traveling vibration actuator is shown in FIG. 8 as a first application example.
Another example will be described based on FIG. 9 as a second usage example. Here, these vibration actuators are claimed in claim 1.
It corresponds to the invention described in 0. In the first embodiment, the same parts as those described with reference to FIGS. 1 and 2 as the description of the vibrator 1 are designated by the same reference numerals and the description thereof will be omitted (same below).

<Vibrator> First, in the present embodiment, the oscillator 1
A concave portion 21 is formed on the outer surface of each side 3 a of the elastic body 3 in the above, and the piezoelectric body 4 is bonded to the concave portion 21. The piezoelectric bodies 4 are set in such a positional relationship that they do not protrude from the surface including the outer surface of each side of the elastic body 3.

In such a configuration, the vibrator 1 driven by the drive unit 5 has the sides 3a as in the first embodiment.
Elliptical vibration is generated in the central portion and each corner portion 3b. Such a state is illustrated in FIG. Then, the elliptical vibration is enlarged at the corners 3b, and a larger driving force can be taken out from these corners 3b.

<Self-propelled Vibration Actuator as First Use Example of Vibrator> Next, as a first use example of the vibrator 1 illustrated in FIGS. 6 and 7, an example of a self-propelled vibration actuator is shown. It shows in FIG. First, a linear rail 22 is provided, and a pressure contact member 23 is provided as a pressure contact means for slidably attaching the vibrator 1 to the rail 22 by pressing one side 3a of the vibrator 1 against the rail 22. Here, the self-propelled vibration actuator 2 is
4 are configured.

Here, the vibrator 1 is arranged so that one side 3a thereof abuts on the rail 22. The pressure contact member 23 is connected to the space 2 of the vibrator 1.
A U-shaped mounting base portion 26 that is in contact with the rail 22 via an elastic material 25 made of a rubber material or the like and that faces the rail 22 in a non-contact state, and is disposed between the mounting base portion 26 and the vibrator 1. An abutting body 28 that comes into contact with the vibrator 1 via a bearing 27, the abutting body 28 and the mounting base 26.
And a coil spring 29 that presses the bearing 27 against the vibrator 1 by urging the contact body 28 by being provided in a compressed state.

In such a structure, the vibrator 1 which applies a voltage to the piezoelectric body 4 from the drive unit 5 and contacts the rail 22
Elliptical vibrations in the same direction as illustrated in FIGS. As a result, the corner 3 of the vibrator 1
Due to the friction between b and the rail 22, the vibrator 1 is pressed against the pressing member 23.
Self-propelled with. Switching the traveling direction of the vibrator 1 is facilitated by switching the direction of the elliptical vibration generated in the corner portion 3b.

Such a self-propelled vibration actuator 2
As an example of use of No. 4, a carrier such as an optical pickup element can be considered. That is, by arranging the rails 22 along the radial direction of the optical medium and arranging the optical pickup element in the space 2 of the vibrator 1, a carrier for moving the optical pickup element in the radial direction of the optical medium is constituted. It
With this configuration, the driven body such as the optical pickup element is arranged in the space 2 of the vibrator 1, and an extremely compact device can be obtained.

<Self-propelled Vibration Actuator as Second Use Example of Vibrator> Next, as a second use example of the vibrator 1 illustrated in FIGS. 6 and 7, another self-propelled vibration actuator will be described. An example is shown in FIG. First, a pair of linear rails 31 arranged in parallel is provided, and the vibrator 1 is arranged between these rails 31. This oscillator 1
Are pressed against the rails 31 by pressing means (not shown) and slidably held by these rails 31. The vibrator 1 has a corner 3b on one side 3a.
Directly contacts one of the rails 31a, and the side 3a opposite to the side 3a of the other rail 31b is interposed via the intermediate member 32.
Is arranged so as to abut. Here, a self-propelled vibration actuator 33 is configured.

Here, the intermediate member 32 is a flat plate pressure contact plate 35 attached to one side 3a of the vibrator 1 via a cushioning material 34, and a pair of rotatably attached to the pressure contact plate 35. And a bearing 36. The positions of these bearings 36 are such that they come into contact with the corners 3b of the vibrator 1 and the rails 31b.

In such a structure, a voltage is applied from the drive unit 5 to the piezoelectric body 4, and the four corners 3b are shown in FIGS.
An elliptic vibration in the same direction as illustrated in FIG. Then, the corner portion 3 of the vibrator 1 in contact with the bearing 36
The elliptic vibration of b is transmitted to the bearing 36, and the bearing 36 rotates in the direction opposite to the direction of the elliptic vibration. The direction is indicated by an arrow in FIG. Therefore, the driving direction transmitted from the vibrator 1 to the rail 31a and the driving direction transmitted to the rail 31b are coincident with each other, and the vibrator 1 is self-propelled together with the pressure contact member 32. Switching the traveling direction of the vibrator 1 is facilitated by switching the direction of the elliptical vibration generated in the corner portion 3b of the vibrator 1.

Such a self-propelled vibration actuator 3
As an example of use of No. 3, as well as the vibration actuator 24 described with reference to FIG. 8, a carrier of an optical pickup element can be considered.

<First Modified Example of Vibrator> Here, modified examples of the vibrator 1 illustrated in FIGS. 6 and 7 are shown in FIGS. The modified example of the vibrator 1 corresponds to the invention described in claims 4 and 6. That is, as illustrated in FIG. 10B, one of the piezoelectric bodies 4 provided on the vibrator 1 is divided into two in the direction orthogonal to the longitudinal direction thereof and is connected to the drive unit 5. It is divided into a body 4a and a piezoelectric body 4b connected to a voltage detection circuit (not shown). Such a configuration corresponds to the invention described in claim 4. Each piezoelectric body 4 has a shape with both ends removed, and is formed so as not to contact the corner portion 3 b of the elastic body 3. Such a structure corresponds to the invention of claim 6.

Thus, the vibration occurring in the vibrator 1 is detected by extracting the voltage generated in the one piezoelectric body 4b divided into two when the vibrator 1 is deformed and checking the value with the voltage detection circuit. Thus, feedback control of the vibrator 1 can be realized. Further, since both ends of each piezoelectric body 4 are removed, the piezoelectric body 4 is separated from the grounded elastic body 3 to prevent a short circuit or discharge to the elastic body 4. Therefore, the device can be made highly safe.

Although this modification has been described as a modification of the vibrator 1 in the second embodiment corresponding to the invention described in claim 2, the first embodiment corresponding to the invention described in claim 1. It may be configured as a modified example of the vibrator 1 in.

<Second Modification of Vibrator> FIG.
(a) and (b) show the vibrator 1 illustrated in FIGS. 6 and 7.
Is a modified example of the above and corresponds to the invention of claim 5. In this modification, both ends of the piezoelectric body 4 provided on the vibrator 1 are divided in the longitudinal direction, and are divided into a piezoelectric body 4a located at the central portion to which the drive unit 5 is connected and a piezoelectric body 4b located at both ends. It is divided.

As a result, the piezoelectric body 4 is separated from the grounded elastic body 3, and a short circuit or discharge to the elastic body 3 is prevented. Therefore, the device can be made highly safe. Further, the piezoelectric body 4 is bonded over the entire length of the side 3a in the recess 21 of the elastic body 3, and then both ends thereof are divided. Therefore, when the piezoelectric body 4 is bonded to the elastic body 3, the bonding position is not delicate, the workability is improved, and the manufacturing is facilitated.

Although this modification has been described as a modification of the vibrator 1 in the second embodiment corresponding to the invention described in claim 2, the first embodiment corresponding to the invention described in claim 1. It may be configured as a modified example of the vibrator 1 in.

[Third Embodiment] As a third embodiment of the present invention, an example of a vibration actuator according to claim 11 will be described with reference to FIGS. 12 and 13. The vibration actuator 41 in this embodiment is of a self-propelled type that is self-propelled along a pair of linear rails 42 arranged in parallel.

First, one of the rails 42 is formed with a tapered corner regulating surface 43 as a regulation surface, and the other rail 42b is provided with a tapered projection regulating surface 44 as a regulation surface. The portion 45 is formed. The corner regulation surface 43 and the protrusion regulation surface 44 are configured to face each other.

Next, in the vibrator 1, recesses 46 are formed in the center of each side 3a, and the piezoelectric body 4 is bonded to these recesses 46 without protruding from the surface including the outer surface of each side 3a. There is. Further, the vibrator 1 is formed with a protrusion 47 located on the lower surface of the central portion of each side 3a. These protrusions 47 correspond to the protrusion restricting surface 44,
Each corner 3b of the elastic body 3 is formed in a tapered shape corresponding to the corner restriction surface 43. In the vibrator 1 thus formed, the corner 3b on one side 3a is in contact with the corner regulating surface 43, and the protrusion 47 formed on the side 3a facing the side 3a is projected. It is placed on the rail 42 so as to come into contact with the section regulation surface 44.

In such a configuration, the piezoelectric body 4 is driven by the drive unit 5 to drive the piezoelectric body 4 and the central portion and the corner portion 3 of the side 3a of the vibrator 1.
An elliptic vibration as illustrated in FIG. 2 is generated in b and. Then, as illustrated in FIG. 12A, the corner portion 3b of the vibrator 1 that abuts on the corner restriction surface 43 and the protrusion 47 formed on the side 3a of the vibrator 1 that abuts on the projection restriction surface 44. Elliptical vibrations generated in and are in opposite directions. As a result, the oscillator 1
Runs on the rail 42. Since the traveling direction of the vibrator 1 is determined by the direction of the elliptical vibration, the traveling direction of the vibrator 1 can be easily switched by switching the direction of the elliptical vibration generated in the vibrator 1.

Such a self-propelled vibration actuator 4
As an example of use of No. 1, as well as the self-propelled vibration actuators 24 and 33 described as the first and second examples of use of the vibrator 1 in the second embodiment, a carrier such as an optical pickup element is considered. To be That is, the rail 42 is arranged along the radial direction of the optical medium, and the space 2
By arranging the optical pickup element in the optical disk, a carrier for moving the optical pickup element in the radial direction of the optical medium is formed. As a result, a driven body such as a pickup element is arranged in the space 2 of the vibrator 1, and an extremely compact device can be obtained.

In carrying out the invention, the protrusion regulating surface 44
It is also possible to form only the protrusion 47 that abuts against the other protrusion 47 and omit the other protrusions 47. Further, the vibrator 1 used in this embodiment is
Although the configuration is similar to that of the vibrator 1 in the second embodiment corresponding to the invention described in claim 2, it is similar to that of the vibrator 1 in the first embodiment corresponding to the invention described in claim 1. You may use the one.

[Fourth Embodiment] As a fourth embodiment of the present invention, an example of a vibration actuator according to claims 8 and 9 will be described with reference to FIGS. 14 to 17. The vibration actuator 51 in this embodiment is a rotary type in which the vibrator 1 is used as a stator.

First, as illustrated in FIG. 17, a regular square mounting portion 53 is fixed on a circular substrate 52, and a base 55 on which a shaft portion 54 is erected is provided on the mounting portion 53. ing. As for the standing position of the shaft portion 54, its shaft center is the mounting portion 5.
It is a position passing through the center of 3. A screw portion 54a is formed at the end of the shaft portion 54.

Then, as shown in FIG. 14, the space portion 2 of the vibrator 1 is fitted into the mounting portion 53 with a cushioning material 56 made of a rubber material or the like interposed therebetween, whereby the base 55
The vibrator 1 is attached to the. This oscillator 1
As shown in FIG. 15, a concave portion 57 is formed at the center of each side 3a.
The piezoelectric bodies 4 are adhered to these recesses 57 so as not to project from the surface including the outer surface of the side 3a.
In addition, each corner 3b of the vibrator 1 has a tapered surface 58.
Are formed.

Next, a rotor 60 as a disk-shaped moving body is rotatably attached to the shaft portion 54 of the base 55 via a bearing 59. This rotor 6
0 is a tapered surface 5 formed on the corner 3b of the vibrator 1.
8 and a tapered surface 61 is formed at a position where these tapered surfaces 58 come into contact with each other. Then, in this state, the spring 62 is inserted into the shaft portion 54, and the nut 63 screwed into the screw portion 54a of the shaft portion 54 is tightened. Therefore, the rotor 60 is in pressure contact with the vibrator 1 via the respective tapered surfaces 58 and 61.

In such a structure, when the driving section 5 drives the piezoelectric body 4 to cause elliptical vibration as illustrated in FIG.
0 is driven and rotates. At this time, it is possible to rotate the rotor 60 in both forward and reverse directions by switching the direction of elliptical vibration. Further, the vibrator 1 and the rotor 60 are
Since they are pressed against each other via the tapered surfaces 58 and 61,
The contact area is wide. As a result, it is possible to obtain a device having excellent durability and generating a strong driving force.

Since the rotor 60 is in contact with the vibrator 1 in the orthogonal direction, the overall shape of the vibration actuator 51 is flattened, and the vibration actuator 51 having an extremely small thickness can be obtained. Further, similar to a general vibration motor, it has a characteristic that a large torque can be obtained at a low rotation speed, and the rotor 60 can be held to prevent its free rotation when driven.

Further, in this embodiment, power can be taken out from the outer peripheral surface of the rotor 60. Therefore, the outer peripheral surface of the rotor 60 can be surface-treated with a high-friction material and used as a roller as it is, or by applying a belt to take out a driving force, or by cutting a tooth and using it as a gear.

[Fifth Embodiment] As a fifth embodiment of the present invention, an example of a vibrator according to claims 3 and 7 will be described with reference to FIGS. 18 to 20, and rotation using the vibrator will be described. An example of the mold type vibration actuator will be described with reference to FIGS. 21 to 23. This vibration actuator corresponds to the invention described in claims 8 and 9.

<Vibrator> The oscillator 1 of this embodiment is characterized by the space 2. That is, the elastic body 3 has a great circle 71 centered at the intersection of the two diagonal lines, that is, the center point.
Are formed, and four small circles 72 that are located near the four corners 3b and communicate with the great circle 71 are formed. The formation positions of these small circles 72 are positions where all four small circles 72 are symmetrical. The space 2 is formed by the large circle 71 and the small circle 72 formed at such positions.

In such a structure, the operating principle of the vibrator 1 is as described in the first embodiment based on FIG. The elliptical vibration generated in the central portion of each side 3a and each corner portion 3b when driven by the driving portion 5 is shown by a solid line and a dotted line in FIG.

Here, in this embodiment, the large circle 71 and the small circle 7
Since the space portion 2 is formed by the hole portion 2, the space portion 2 can be formed only by making a hole in the elastic body 3, which simplifies the manufacturing process and facilitates manufacturing. It can be facilitated.

<Rotary Vibration Actuator Utilizing Vibrator> Next, an example of a rotary vibration actuator utilizing the vibrator 1 is shown in FIGS. 21 to 23. The vibration actuator 73 has the same structure as the vibration actuator 7 described based on FIGS. 3 to 5 as an example of using the vibrator 1 in the first embodiment except the structure of the vibrator 1. Therefore, its explanation is omitted.

[Sixth Embodiment] As a sixth embodiment of the present invention, an example of the vibrator according to claims 2, 3 and 7 is shown in FIG.
25 and an example of a self-propelled vibration actuator using the vibrator will be described with reference to FIG. This vibration actuator corresponds to the invention of claim 10.

<Oscillator> The oscillator 1 of this embodiment is configured like the oscillator 1 of the second embodiment with respect to the side 3a of the elastic body 3, and is the same as that of the fifth embodiment with respect to the space 2. Oscillator 1
It is configured like. That is, a concave portion 81 is formed in the central portion of each side 3a, and the piezoelectric body 4 is formed in each of the protrusions 81 so as not to project beyond the plane including the outer surface of each side 3a.
Are glued together. Then, the elastic body 3 is formed with a great circle 82 centered on the intersection of the two diagonal lines, that is, the center point, and four great circles 82 located near the four corners 3b and communicating with the great circle 82 are formed. A small circle 83 is formed. The formation positions of these small circles 83 are positions where all four small circles 83 are symmetrical. The space 2 is formed by the large circle 82 and the small circle 83 formed at such positions.

In such a structure, the operating principle of the vibrator 1 is as described in the first embodiment based on FIG. Further, the advantages and the like of providing the concave portion 81 are as described in the second embodiment, and the description thereof will be omitted.

Here, in this embodiment, like the vibrator 1 of the fifth embodiment, since the space portion 2 is formed by the hole portions of the large circle 82 and the small circle 83, the elastic body 3 is The space portion 2 can be formed only by punching holes, which simplifies the manufacturing process and facilitates manufacturing.

<Self-propelled vibration actuator using vibrator> Next, an example of a self-propelled vibration actuator using the vibrator 1 is shown in FIG. The vibration actuator 84 has the same structure as that of the vibration actuator 23 described with reference to FIG. 8 as the first example of use of the vibrator 1 in the second embodiment except the structure of the vibrator 1. Therefore, its explanation is omitted.

[Seventh Embodiment] As a seventh embodiment of the present invention, an example of the vibration actuator according to the twelfth embodiment will be described with reference to FIGS. 26 and 27. The structure of the vibrator used in this embodiment is similar to that of the vibrator 1 described in the fifth embodiment. Therefore, regarding the vibrator 1, the same parts as those of the vibrator 1 of the fifth embodiment are denoted by the same reference numerals, and the description thereof will be omitted.

First, in this embodiment, the space portion 2 of the vibrator 1 is
A vibrator-side threaded portion 91 that is a screw hole is cut around a great circle 71 that forms Then, a tubular moving body 92 is provided, and a moving plate side screw portion 93 which is a screw to be screwed into the transducer side screw portion 91 is formed on the moving body 92. The vibration actuator 94 is configured here.

In such a structure, as shown in FIG. 27A, the vibrator-side screw portion 91 is the central portion of each side 3a of the elastic body 3. Therefore, in the vibrator 1 driven by the driving unit 5, elliptical vibration is generated in the vibrator-side screw portion 91. As a result, the moving body side screw portion 93 of the moving body 92 is rotated, and the moving body 92 rotates. Such a moving body 92
With the rotation of the moving body 92, the moving body 92 moves in the screwing direction of the moving body side screw portion 93. That is, as shown by the solid or dotted arrows in FIG. 26, the moving body 92 moves in the axial direction while rotating. The rotation direction and the movement direction of the moving body 92 are determined by the direction of the elliptical vibration generated in the vibrator-side screw portion 91 of the vibrator 1. As described above, in this embodiment, the special vibration actuator 94 that moves the moving body 92 in the axial direction while rotating it is obtained.

[0085]

The vibrator according to the first aspect of the invention includes a flat rectangular elastic body having a space at the center and piezoelectric bodies fixed to the four sides of the elastic body. When the piezoelectric body is driven by the driving unit in the invention according to claim 7, elliptical vibration can be generated at the corners and the central portions of the sides of the elastic body, and the direction of the elliptical vibration can be easily switched. Therefore, it is possible to obtain a highly versatile vibrator that can be used for various types of vibration actuators, and it is possible to make the whole compact.
Therefore, the drive source can be easily arranged even in a narrow installation space, which can enhance versatility as a drive source, and further, a structure in which a piezoelectric body having low strength is fixed to an elastic body. Therefore, the strength is higher than that of a vibrator which is entirely composed of a piezoelectric body, and therefore, an effect that a large driving force can be obtained is obtained.

A vibrator according to a second aspect of the invention is the vibrator according to the first aspect, wherein a recess is formed in a portion of the elastic body to which the piezoelectric body is fixed, and the piezoelectric body is more piezoelectric than a surface including each side of the elastic body. Since the body is set so as not to project, it is possible to form a vibration actuator in which a vibrator is directly pressure-contacted to a planar one, and therefore, versatility as a drive source can be further enhanced. Also, at the corners of the elastic body, the vibration generated at these corners can be magnified,
Therefore, it is possible to obtain a larger driving force at the corners of the elastic body.

A vibrator according to a third aspect of the present invention is the vibrator according to the first or second aspect, wherein the space portion has a great circle centered at an intersection of two diagonal lines of the elastic body and the great circle. Since it is formed by the small circles respectively arranged at symmetrical positions in the vicinity of the four corners of the elastic body communicating with, the space portion of the elastic body can be formed only by punching the elastic body, Therefore, the manufacturing process can be simplified and the manufacturing can be facilitated.

A vibrator according to a fourth aspect of the present invention is the vibrator according to the first, second or third aspect, wherein at least one piezoelectric body is divided into two in a direction orthogonal to a longitudinal direction of a side of the elastic body. Therefore, it is possible to detect the vibration occurring in the vibrator by extracting the voltage generated in one of the piezoelectric bodies divided into two parts and checking the value, and therefore it is possible to easily realize the feedback control of the vibrator. It has the effect that it can be done.

A vibrator according to a fifth aspect of the present invention is the vibrator according to the first, second or third aspect, wherein both ends of each piezoelectric body are divided in the longitudinal direction of the sides of the elastic body. According to a sixth aspect of the invention, in the vibrator according to the first, second or third aspect, the piezoelectric body has a shape in which both ends of each piezoelectric body are removed. Can be prevented from short-circuiting or discharging to the elastic body, thus eliminating the risk of discharge during and after manufacturing and ensuring safety during manufacturing and use. Have an effect.

A vibrator according to a seventh aspect of the present invention is the vibrator according to the first, second, third, fourth, fifth or sixth aspect, in which each side of the elastic body is generated by applying a voltage to the piezoelectric body. Since it further includes a driving unit that causes elliptical vibration at the corners of the elastic side or the central portion of the side by using the bending, the bending direction of each side of the elastic body generated by applying a voltage to the piezoelectric body is set to a predetermined value. By setting the direction, elliptical vibration can be generated at the corners and the center of the side of the elastic body, and the direction can be easily switched. At this time, the bending mode of the elastic body is used. Therefore, there is an effect such that the amplitude of the elliptical vibration can be increased and a large driving force can be obtained.

A vibrating actuator according to an eighth aspect of the present invention is a vibrating element according to the first, second or third aspect of the present invention, and a moving body that is in pressure contact with at least one corner portion or at least one central portion of the side of the vibrating element. Therefore, elliptical vibration is generated in the elastic body portion where the moving body presses, power is transmitted to the moving body, and rotational movement or linear movement can be generated in the moving body. This can be realized by an extremely simple structure in which the moving body is simply brought into pressure contact with a predetermined position of the vibrator, and therefore, the device can be simplified, and so on.

A vibration actuator according to a ninth aspect of the present invention is the vibration actuator according to the eighth aspect,
Since the moving body is pressed against the vibrator in the orthogonal direction, and the pressure contact portion between the vibrator and the moving body is formed on the tapered surface, the contact area between the elastic body and the moving body can be widened. Therefore, a large driving force can be obtained, and since the moving body is pressed against the vibrator from the orthogonal direction, it is possible to form the whole flatter and to downsize the device. Further, the drive source can be easily arranged even in a narrow installation space, and thus, the versatility of the drive source can be improved.

According to a tenth aspect of the invention, there is provided a vibration actuator comprising: the vibrator according to the second aspect or the vibrator according to the second and third aspects; a rail; and pressure contact means for pressing one side of the vibrator against the rail. Therefore, by generating elliptical vibration at the corner of the vibrator that is pressed against the rail of the elastic body, the vibrator can be easily self-propelled along the rail. The vibration actuator can be easily realized, and by disposing a driven object such as an optical pickup element in the space of the vibrator, it is possible to contribute to downsizing of the entire device in which the vibration actuator is used. And so on.

A vibrating actuator according to an eleventh aspect of the present invention includes a vibrator according to the first, second or third aspect, a pair of rails for slidably holding the vibrator, and a rail of an elastic body in the vibrator. Since it includes a protrusion formed to protrude from the central portion of the parallel sides, and a regulation surface formed on the rail that regulates the movement of the protrusion and the corner portion of the elastic body in the direction orthogonal to the sliding direction of the vibrator. , By causing elliptical vibration at the corners of the two sides of the oscillator parallel to the rail and the center of the side, the oscillator can easily be self-propelled along the rail. A self-propelled vibration actuator having a structure can be easily realized, and a vibration actuator is used by disposing a driven object such as an optical pickup element in a space of a vibrator. An effect such can contribute to the miniaturization of the body.

A vibration actuator according to a twelfth aspect of the present invention is a vibrator according to the third aspect, a vibrator-side screw portion formed around a great circle forming a space of the vibrator, and the vibration. Since it includes a moving body having a moving body side screw portion that is screwed to the child side screw portion, elliptical vibration is generated in the vibrator side screw portion of the elastic body of the vibrator, thereby rotating the moving body side screw portion of the moving body. Therefore, it is possible to obtain a special vibration actuator in which the moving body moves in the axial direction while rotating, and so on.

[Brief description of drawings]

FIG. 1 is a plan view of a vibrator showing a first embodiment of the present invention.

FIG. 2 is a plan view illustrating the vibration mode.

FIG. 3 shows an example of use of the vibrator shown in FIGS. 1 and 2.
FIG. 3 is a vertical sectional front view showing an example of a rotary vibration actuator.

FIG. 4 shows a stator of the rotary vibration actuator, in which (a) is a plan view and (b) is a vertical sectional front view.

5A and 5B show a rotor of the rotary vibration actuator, in which FIG. 5A is a plan view and FIG. 5B is a vertical sectional front view.

FIG. 6 is a plan view of a vibrator showing a second embodiment of the present invention.

FIG. 7 is a plan view illustrating the vibration mode.

FIG. 8 shows an example of a self-propelled vibration actuator as a first application example of the vibrator shown in FIGS. 6 and 7.
(A) is a front view, (b) is a vertical side view.

9 is a front view showing another example of a self-propelled vibration actuator as a second application example of the vibrator shown in FIGS. 6 and 7. FIG.

FIG. 10 shows a first modification of the vibrator shown in FIGS. 6 and 7, (a) being a plan view and (b) being a front view.

11 shows a second modification of the vibrator shown in FIGS. 6 and 7, (a) being a plan view and (b) being a front view.

FIG. 12 is a self-propelled vibration actuator showing a third embodiment of the present invention, (a) is a plan view and (b) is a vertical sectional front view.

FIG. 13 shows an example of a vibrator used in the self-propelled vibration actuator, in which (a) is a plan view and (b) is a front view.

FIG. 14 is a vertical sectional front view of a rotary vibration actuator showing a fourth embodiment of the present invention.

FIG. 15 is a plan view of a stator used in the rotary vibration actuator.

FIG. 16 shows a rotor used for the rotary vibration actuator, in which (a) is a plan view and (b) is a vertical front view.

FIG. 17 shows a base of the rotary vibration actuator, (a) is a plan view and (b) is a front view.

FIG. 18 is a plan view of a vibrator showing a fifth embodiment of the present invention.

FIG. 19 is a plan view of an elastic body of the vibrator.

FIG. 20 is a plan view illustrating a vibration mode of the vibrator.

FIG. 21 is a vertical cross-sectional front view showing an example of a rotary vibration actuator as an application example of the vibrator shown in FIGS. 18 to 20.

FIG. 22 shows a stator used for the rotary vibration actuator, in which (a) is a plan view and (b) is a vertical front view.

FIG. 23 shows a rotor used for the rotary vibration actuator, in which (a) is a plan view and (b) is a vertical front view.

FIG. 24 is a plan view of a vibrator showing a sixth embodiment of the present invention.

FIG. 25 shows an example of a self-propelled vibration actuator as an example of use of the vibrator shown in FIG. 24, (a) being a front view,
(B) is a vertical side view.

FIG. 26 is a front view of a vibration actuator showing a seventh embodiment of the present invention.

FIG. 27 shows a vibrator used for the actuator, in which (a) is a plan view and (b) is a vertical sectional front view.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 vibrator 2 space part 3 elastic body 3a side 3b corner part 4 piezoelectric body 5 drive part 7, 24, 33, 41, 51, 73, 84, 94
Vibration actuator 11, 60, 92 Moving body 15, 16, 58, 61 Tapered surface 21, 46, 81 Recessed portion 22, 31, 42 Rail 23 Pressure contact means 43, 44 Restriction surface 47 Projection portion 71, 82 Great circle 72, 83 Small Circle 91 Transducer side thread 93 Mobile unit side thread

Claims (12)

[Claims] 1. A vibrator comprising a flat quadrangular elastic body having a space at its center, and piezoelectric bodies fixed to the four sides of the elastic body. 2. A concave portion is formed in a portion of the elastic body to which the piezoelectric body is fixed, and the piezoelectric body is set so as not to protrude from a surface including each side of the elastic body. The vibrator according to Item 1. 3. The space portion is arranged at a symmetrical position in the vicinity of a great circle whose center is an intersection of two diagonal lines of the elastic body and four corners of the elastic body which communicate with the great circle. 3. The vibrator according to claim 1, which is formed by a small circle. 4. The vibrator according to claim 1, wherein at least one piezoelectric body is divided into two in a direction orthogonal to the longitudinal direction of the side of the elastic body. 5. The piezoelectric element according to claim 1, wherein both ends of each piezoelectric element are divided in the longitudinal direction of the sides of the elastic element.
The described oscillator. 6. The vibrator according to claim 1, wherein each piezoelectric body has a shape in which both ends thereof are removed. 7. A drive unit is further included, which uses the curvature of each side of the elastic body generated by applying a voltage to the piezoelectric body to generate elliptical vibration at a corner portion or a central portion of the elastic side. The vibrator according to claim 1, 2, 3, 4, 5 or 6. 8. A vibration actuator, comprising: the vibrator according to claim 1, 2 or 3; and a moving body that is in pressure contact with at least one corner of the vibrator or a central portion of at least one side. . 9. The vibration actuator according to claim 8, wherein the moving body is pressed against the vibrator in a direction perpendicular to the vibrator, and the pressure contact portion between the vibrator and the moving body is formed into a tapered surface. . 10. A vibration actuator comprising: the vibrator according to claim 2 or the vibrator according to claims 2 and 3, a rail, and a pressure contact means for pressing one side of the vibrator to the rail. . 11. A vibrator according to claim 1, 2, or 3,
A pair of rails that hold this oscillator slidably,
A protrusion formed to protrude from the center of a side of the elastic body of the vibrator parallel to the rail, and movement of the protrusion and a corner of the elastic body in a direction orthogonal to the sliding direction of the vibrator. A vibration actuator, comprising: a restriction surface formed on the rail for restriction. 12. The vibrator according to claim 3, a vibrator-side screw portion formed around a great circle forming a space portion of the vibrator, and a movable body side screwed to the vibrator-side screw portion. A vibration actuator, comprising: a moving body having a screw portion.