JPH0732613B2 - Ultrasonic oscillator and drive device having this oscillator - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an ultrasonic vibrator using an electromechanical conversion element such as a piezoelectric element as a vibration source, and a drive device having the vibrator.

[Prior Art] Ultrasonic motors have recently been in the spotlight as new motors that replace electromagnetic motors. This ultrasonic motor is not only new in principle, but also has the following advantages over conventional electromagnetic motors.

 Thin, lightweight and compact.

 Low speed and high torque can be obtained without gears.

 The parts configuration is simple and highly reliable.

 There is no exchange of magnetic effects.

 Positioning is easy with no backlash.

Thus, in order to make use of these advantages, various applied technologies are being researched.

Ultrasonic motors are roughly divided into ring type and linear type. 14 to 17 are views showing a conventional example of a linear type ultrasonic motor.

FIG. 14 is a diagram showing a first conventional example. When the Langevin type piezoelectric vibrator 1 on the left side in the figure is vibrated and the tip of the horn 2 is applied to the propagation rod 3 made of an elastic body, a bending traveling wave is generated in the propagation rod 3. This bending traveling wave is indicated by the solid arrow D
As shown by, the propagating rod 3 propagates rightward. Then, this traveling wave excites the Langevin type piezoelectric vibrator 5 via a similar horn 4 applied to the right end of the propagating rod 3. At this time, L and R in the figure are appropriately selected and impedance matching is performed to absorb all the energy of the traveling wave. By doing so, the traveling wave always proceeds from the left to the right constantly.

When the slider 6 is held in pressure contact with the surface of the propagation rod 3 in which such a bending traveling wave is generated by a certain pressing force, the slider 6 moves leftward in the figure as indicated by a solid arrow H. Go.

FIG. 15 is a perspective view schematically showing the relationship between the bending traveling wave of the propagation rod 3 and the slider 6. In the figure, 3A is an elastic body corresponding to the propagation rod 3, and 6A is a moving body corresponding to the slider 6. As shown in FIG. 15, the mass point P of the elastic body 3A draws an elliptical locus. Therefore, when the moving body 6A is brought into pressure contact with the elastic body 3A that draws a counterclockwise elliptical locus in this figure with a predetermined pressure, the moving body 6A is in a direction opposite to the traveling direction D of the traveling wave, that is, in the left direction in the figure. Driven to. If the traveling direction of the traveling wave is reversed, the moving body 6A is driven rightward in the figure.

FIG. 16 is a diagram showing the configuration of another conventional example. A vibrating piece 8 is attached to the tip of the Langevin type vibrator 7.
The tip of the vibrating body 8 is in contact with the slider 6B with a constant pressing force in a state of being inclined at a predetermined angle θ with respect to the normal line of the surface of the slider 6B. When an AC voltage having the same frequency as the natural frequency of the Rambaju type vibrator is applied from the AC power source 9 to the Rambaju type vibrator 7,
The Langevin type vibrator 7 performs longitudinal vibration. At this time, since the tip of the vibrating piece 8 is in contact with the slider 6B at a predetermined angle θ, lateral vibration is also performed. By combining these vibrations, the tip of the vibrating piece 8 draws an elliptical locus. Thus slider
6B moves to the left as shown by the arrow in the figure.

FIG. 17 is a diagram showing still another conventional example.
The configuration of the oscillator disclosed by No. 78 is shown. Piezoelectric elements 11 and 12 are bonded to both surfaces of a rectangular-shaped conductive vibrator 10. Lead terminals A and B for voltage application are drawn from the piezoelectric elements 11 and 12, and from the vibrator 10,
The ground terminal E is pulled out. The shape of the vibrator 10 is such that the resonance frequency of longitudinal vibration of the vibrator 10 and the resonance frequency of flexural vibration match. Thus, when an AC voltage having the above resonance frequency is applied to the lead terminals A and B with a constant phase difference, the mass point of the end surface S of the vibrator 10 makes an elliptic motion. Therefore, when the slider 6C is pressed against the end surface S with a constant force, the slider 6C moves in the direction of arrow HH in the figure. This moving direction is determined by the phase difference between the voltages applied to the terminals A and B.

[Problems to be Solved by the Invention] The ultrasonic motor shown in FIGS. 14 to 17 is based on the principle that friction energy of the elliptical locus motion at the mass point of the oscillator is transmitted to the moving body (slider) by friction. There is.

In the first conventional example shown in FIG. 14, since traveling waves have to be generated in the entire propagation rod 3, there is a problem that efficiency is poor and the entire apparatus becomes large. Again
In the second conventional example shown in FIG. 16, there is a problem that the traveling direction of the slider 6B is limited to one direction, and the entire device becomes large as in the first conventional example. Further, in the third conventional example shown in FIG. 17, since the vibration output is obtained by the piezoelectric elements 11 and 12 adhered to both sides of the vibrator 10, a large force for moving the slider 6C can be secured. Have difficulty. If the number of piezoelectric elements 11 and 12 bonded to the side surface of the vibrator 10 is increased in order to obtain a larger vibration output, there is a drawback that the device becomes larger by that amount. Further, the conventional example shown in FIG. 17 above is intended to generate elliptical vibration by combining longitudinal vibration and flexural vibration of the vibrator 10, but if both vibrations are not in a resonance state, a large output is produced. I can't get it. Therefore, it is necessary to match the resonance frequency of longitudinal vibration with the resonance frequency of flexural vibration. For this reason, the shape of the vibrator 10 must be determined by trial and error, which requires a large amount of labor and is not easy to manufacture.

Therefore, an object of the present invention is to have a compact size, good energy conversion efficiency, and a large vibration output,
An object of the present invention is to provide an ultrasonic oscillator that can reversibly move an object to be driven when used as a linear motor, has few design restrictions, and is easy to manufacture, and a drive device including this oscillator.

[Means for Solving the Problems] In order to solve the above problems and achieve the object, an ultrasonic transducer and a driving device of the present invention are configured as follows.

(1) The ultrasonic transducer of the present invention comprises a plurality of rectangular plate-shaped piezoelectric elements, a square plate for output extraction arranged at one end, and a square plate for fixation arranged at the other end. A piezoelectric laminated body formed by laminating a plate, and two side surface rectangular plate-shaped piezoelectric elements joined to two opposing two sides of the four side surfaces parallel to the laminating direction of the piezoelectric laminated body via insulating members,
An ultrasonic transducer comprising: the piezoelectric laminated body and electric terminals respectively taken out from the side surface rectangular plate-shaped piezoelectric element, wherein an alternating voltage is applied to the piezoelectric laminated body, and a longitudinal direction in a laminating direction is applied to the entire transducer. Vibration is generated, and an alternating voltage is applied to the two side surface rectangular plate-shaped piezoelectric elements facing each other so that they vibrate in opposite phases, thereby causing bending vibration in the entire vibrator,
It is an ultrasonic transducer for generating an ultrasonic elliptical vibration at the position of the output extracting square plate by combining the longitudinal vibration and the bending vibration.

(2) The ultrasonic transducer of the present invention is used for taking out an output, which has a plurality of rectangular plate-shaped piezoelectric elements and a larger dimension in a direction orthogonal to the stacking direction than the rectangular plate-shaped piezoelectric elements arranged at one end. A piezoelectric laminated body in which a square plate and a fixing square plate disposed at the other end and having a dimension larger than the square plate piezoelectric element in a direction orthogonal to the laminating direction are laminated, and both ends of the piezoelectric laminate. Two side surface rectangular plate-shaped piezoelectric elements that are joined together so as to connect the rectangular plates to each other,
An ultrasonic vibrator comprising: the piezoelectric laminate and electric terminals respectively taken out from the side surface rectangular plate piezoelectric elements, wherein a longitudinal vibration in a laminating direction is applied to the whole of the oscillator by applying a voltage to the piezoelectric laminate. Is generated, and an alternating voltage is applied to the two opposed side surface rectangular plate-shaped piezoelectric electrons so that they vibrate in opposite phases, thereby causing bending vibrations in the entire vibrator, and the longitudinal vibrations and the bending vibrations are generated. This is an ultrasonic transducer for generating ultrasonic elliptical vibration at the position of the square plate for taking out the output by combining and.

(3) The ultrasonic transducer of the present invention includes a plurality of rectangular plate-shaped piezoelectric elements, a rectangular plate for output extraction arranged at one end, and a fixing square arranged at the other end. A piezoelectric laminated body formed by laminating a plate, two side surface rectangular plate-shaped piezoelectric elements bonded to two opposing side surfaces of a rectangular plate for fixing the piezoelectric laminated body or a rectangular plate for extracting output, An ultrasonic transducer comprising a piezoelectric laminate and electric terminals respectively taken out from the side surface rectangular plate-shaped piezoelectric element, wherein a voltage is applied to the piezoelectric laminate to cause longitudinal vibration in the lamination direction in the entire oscillator. An alternating voltage is applied to the two opposed side surface rectangular plate-shaped piezoelectric electrons such that they vibrate in opposite phases to generate bending vibration in the entire vibrator, and the longitudinal vibration and the bending vibration are generated. The position of the square plate for extracting the above output An ultrasonic vibrator for generating ultrasonic elliptical vibration.

(4) The ultrasonic transducer of the present invention comprises a plurality of rectangular plate-shaped piezoelectric elements, a rectangular plate for output extraction arranged at one end, and a fixing square arranged at the other end. A piezoelectric laminated body in which plates are laminated, four side surface rectangular plate-shaped piezoelectric elements joined to four side surfaces parallel to the laminating direction of the piezoelectric laminated body via insulating members, the piezoelectric laminated body, and the piezoelectric laminated body An ultrasonic transducer having electric terminals respectively taken out from the side surface rectangular plate-shaped piezoelectric element, wherein a voltage is applied to the piezoelectric laminated body to generate longitudinal vibration in a laminating direction in the entire transducer, Alternate voltages are applied to the opposing side surface rectangular plate-shaped piezoelectric elements so as to vibrate in opposite phases to generate a first bending vibration in the entire vibrator, and a second opposing side surface rectangular plate shape Apply alternating voltage to the piezoelectric elements as they vibrate in opposite phases. A second bending vibration that is orthogonal to the first bending vibration is generated in the entire vibrator, and the longitudinal vibration, the first bending vibration, and the second bending vibration are combined to obtain the output. It is an ultrasonic transducer for generating ultrasonic elliptical vibration in a plane in an arbitrary direction including a stacking direction at a position of a square plate for use.

(5) The ultrasonic transducer of the present invention is used for taking out an output, which has a plurality of rectangular plate-shaped piezoelectric elements and is arranged at one end and has a larger dimension in the direction orthogonal to the stacking direction than the rectangular plate-shaped piezoelectric elements. A piezoelectric laminated body in which a square plate and a fixing square plate disposed at the other end and having a dimension larger than the square plate piezoelectric element in a direction orthogonal to the laminating direction are laminated, and both ends of the piezoelectric laminate. Vibration having four side surface rectangular plate-shaped piezoelectric elements bonded so as to connect the rectangular plates of the portion, and the electric terminals respectively taken out from the piezoelectric laminate and the side surface rectangular plate-shaped piezoelectric element As a child, a voltage is applied to the piezoelectric laminated body to generate longitudinal vibration in the laminating direction in the entire vibrator, and the first opposed side surface rectangular plate-shaped piezoelectric elements vibrate in opposite phases. Applying an alternating voltage to the first transducer Vibration is generated, and an alternating voltage is applied to the second opposing side surface rectangular plate-shaped piezoelectric elements so that each vibrates in an opposite phase, and a second bending vibration that is orthogonal to the first bending vibration is applied to the entire vibrator. A flexural vibration is generated, and the longitudinal vibration, the first flexural vibration, and the second flexural vibration are combined to form a surface in an arbitrary direction including the stacking direction at the position of the output extracting square plate. It is an ultrasonic transducer that generates ultrasonic elliptical vibration inside.

(6) The ultrasonic transducer of the present invention comprises a plurality of rectangular plate-shaped piezoelectric elements, a rectangular plate for output extraction arranged at one end, and a fixing square arranged at the other end. A piezoelectric laminated body formed by laminating a plate, and four side surface rectangular plate-shaped piezoelectric elements joined to the four side surfaces of a square plate for fixing the piezoelectric laminated body or a square plate for extracting output,
An ultrasonic vibrator comprising: the piezoelectric laminate and electric terminals respectively taken out from the side surface rectangular plate piezoelectric elements, wherein a longitudinal vibration in a laminating direction is applied to the whole of the oscillator by applying a voltage to the piezoelectric laminate. Then, an alternating voltage is applied to the first opposing side surface rectangular plate-shaped piezoelectric elements so that the piezoelectric elements vibrate in opposite phases to generate a first bending vibration in the entire ultrasonic vibrator. , A second bending vibration orthogonal to the first bending vibration is generated in the entire vibrator by applying an alternating voltage to the second facing side surface rectangular plate-shaped piezoelectric elements so that the piezoelectric elements vibrate in opposite phases. Then, by synthesizing the longitudinal vibration, the first bending vibration and the second bending vibration, the ultrasonic ellipse is formed in a plane in an arbitrary direction including the stacking direction at the position of the output extracting square plate. It is an ultrasonic transducer that generates vibration.

(7) A driving device according to the present invention comprises the ultrasonic vibrator according to claim 1, 2 or 3, and a movable member that comes into contact with a square plate for extracting the output of the ultrasonic vibrator. Is configured to be moved in a linear direction.

(8) A drive device according to the present invention comprises the ultrasonic transducer according to claim 4 or 5 and a movable member that comes into contact with a square plate for extracting the output of the ultrasonic transducer. The drive device is configured to be moved in an arbitrary direction within a plane.

[Operation] The following operation is exhibited by taking the above means.
When the piezoelectric layered body and the piezoelectric element attached to the piezoelectric layered body are vibrated, the generated vertical and horizontal vibrations are combined and the combined state is controlled. Elliptical vibration or inclined reciprocating vibration of arbitrary magnitude and mode is performed. Then, when the movable member is brought into contact with the upper surface of the vibrator, the movable member moves in a predetermined direction. In this case, since a laminated piezoelectric actuator is used as the main vibration source, a large mechanical output can be obtained, and the frequency of the drive power supply does not have to match the natural frequency of the elastic body as in the conventional case. Since a large mechanical output can be obtained, it may be driven without resonance, and therefore, there are few design restrictions and it is easy to manufacture.

[First Embodiment] FIGS. 1 to 5 are views showing the configuration of the first embodiment of the present invention. FIG. 1 (a) is a perspective view of an ultrasonic elliptical transducer, and FIG. 1 (b). [Fig. 3] is a top view of the oscillator. The vibrator 20 is composed of a piezoelectric laminated member 25 formed by laminating a large number of plate-shaped piezoelectric elements 21, a piezoelectric element 22, an upper table 23, and a lower table 24.
The piezoelectric elements 21 and 22 have electrodes attached to both sides of piezoelectric ceramics such as PZT by baking treatment of silver or Ni or plating treatment of Ni, and lead wires for grounding and voltage application are connected to these electrodes. Has become. A plurality of piezoelectric elements 21 are stacked so that the polarization directions thereof are alternately reversed, and the piezoelectric elements 21 are bonded and laminated with an adhesive such as epoxy to form a piezoelectric laminated member 25. The upper table 23 is a square plate having a predetermined thickness and made of a metal such as stainless steel or a ceramic material such as alumina. The upper table 23 is adhered to the upper surface of the piezoelectric laminated member 25. Upper stand 23
A hemispherical protrusion 26 is provided at the center of the upper surface of the.
The lower base 24 is made of the same material as the upper base 23,
It is glued to the underside of 25. Further, the lower base 24 is formed with screw holes (not shown) so that it can be easily attached to a base (not shown). A piezoelectric laminated body is configured by the upper base 23 and the lower base 24 on the piezoelectric laminated member 25.

The electrodes connected to the respective piezoelectric elements 21 constituting the piezoelectric laminated member 25 are commonly connected every other layer, and one of the common connections is connected to the terminal A via a lead wire for voltage application, and the other is connected. Is grounded via a grounding lead wire.

The piezoelectric element 22 is a pair of piezoelectric elements as shown in FIG. 1 (b).
The piezoelectric laminate 22a and the piezoelectric element 22b are bonded to both sides of the piezoelectric laminate through insulating members (not shown) so as to face each other and have the same polarization directions. The electrodes on the adhesive surface side of the piezoelectric elements 22a, 22b are grounded,
The electrodes on the outer surface side are commonly connected to the terminal B via a lead wire for voltage application.

FIG. 2 is a diagram showing a configuration of a drive circuit for vibrating the vibrator 20. Reference numeral 30 is an AC power supply that outputs an AC of frequency f. The output of this power supply 30 is given to the terminal B via the phase shifter 31 and the power amplifier 32 on the one hand, and to the terminal A via the power amplifier 33 on the other hand. Given. The phase shifter 31 is capable of shifting the phase of the AC output from the AC power supply 30 from 0 to 360 °. The power amplifiers 32 and 33 are for amplifying the AC power from the AC power supply 30 or the phase shifter 31.

Next, the operation of the vibrator 20 of the present embodiment thus configured will be described with reference to FIGS. When the alternating current of the frequency f from the alternating current power source 30 is amplified by the power amplifier 33 and given to the terminal A, the vibrator 20 vibrates vertically as shown in FIG. 3 (a). The resonance frequency fe of the 1/4 wavelength resonance of this longitudinal vibration is sufficiently higher than the electric input frequency. That is, the longitudinal vibration is vibration due to non-resonance.
On the other hand, in the state where the alternating current from the alternating current power source 30 is phase-shifted by the phase shifter 31 in the range of 0 to 360 °, the power amplifier 32
When it is amplified by and given to the terminal B, the vibrator 20 vibrates laterally, that is, bending vibration as shown in FIG. 3 (b). At this time, resonance driving is performed by matching the resonance frequency fb of the 1/4 wavelength resonance in bending vibration with the electric input frequency. When the above two vibrations are simultaneously excited and the phase shift is controlled, the protrusion 26 draws various loci as shown in FIGS. 4 (a) to (i).

When the oscillator 20 is used as a linear motor (c),
It suffices if the elliptic locus (g) is obtained. Power amplifier
By changing the amplification factors of 32 and 33, it is possible to change the sizes of the components v and u of the elliptical locus shown in FIG.

FIG. 6 is a perspective view showing a modified example of the vibrator 20. This modification is a piezoelectric element 22a, 22 of the vibrator 20 shown in FIG.
While b is adhered in a state in which it is in close contact with the entire side surface of the piezoelectric laminated body, the piezoelectric element 22a, 22b has an upper table 23 and a lower table 24 having an area larger than the area of the laminated surface of the laminated member 25.
It is an example of bonding in a state of bridging against. Even in this case, the operation is similar to that of the vibrator 20 shown in FIG.

FIGS. 7 (a) and 7 (b) are diagrams of other modified examples. This modification is an example in which a square columnar body made of a metal such as stainless steel or a ceramic material such as alumina is used as the lower table 24, and the piezoelectric elements 22a and 22b are bonded to the side walls of the lower table. Also in this modification, the oscillator 20 operates in substantially the same manner as the first illustrated oscillator 20.

In the above-described embodiments, single plates are used as the piezoelectric elements 22a and 22b, but a plurality of piezoelectric elements 22 may be laminated to increase the output of bending vibration. In this case, a large displacement can be obtained even if the bending vibration shown in FIG. 3 (b) is generated without resonance, so that the vertical vibration and the vertical vibration shown in FIG. 3 (a) are eventually obtained. Both the bending vibrations shown in FIG. 3 (b) can be generated without resonance. Further, as the piezoelectric laminated member 25, a plate-shaped piezoelectric element 21 adhered with an adhesive such as an epoxy resin is shown, but electrodes such as platinum are printed on both surfaces of the green sheet, laminated, and integrally fired after pressing. It may be a piezoelectric laminated member produced by the above.

FIGS. 8A to 8D are diagrams showing the configuration of a driving device using the above-described vibrator 20. As shown in FIG. 8A, the plate-shaped slider 40 is brought into contact with the protrusion 26 of the vibrator 20 with a constant pressing force. In this case, the slider 40
As a means for pressing the projection 26 with a constant force, a pressing mechanism 41 including a roller and a spring can be considered as shown in FIG. 8 (b). By using such a pressing mechanism 41, the slider 40 can move smoothly as indicated by the arrow while being pressed against the vibrator 20 with a constant force. In addition, in the portion where the slider 40 is in pressure contact with the protrusion 26,
If a groove 42 having a U-shaped cross section is provided as shown in FIG. 8C, and the projection 26 is engaged with the inner bottom surface of the groove 42 as shown in FIG. By the guide action, the slider 40 can be moved straight.

The piezoelectric laminated body and the piezoelectric element 22a attached to the piezoelectric laminated body,
When 22b is vibrated, the generated longitudinal and lateral vibrations are combined and the combined state is controlled. Therefore, the mass point on the vibrator 10 is an elliptical vibration or an inclined reciprocating reciprocating motion. Vibrate. Then, when the movable member is brought into contact with the upper surface of the vibrator 10, the movable member moves in a predetermined direction. In this case, since a laminated piezoelectric actuator is used as the main vibration source, a large mechanical output can be obtained, and the frequency of the drive power supply does not have to match the natural frequency of the elastic body as in the conventional case. Since a large mechanical output can be obtained, it may be driven without resonance, so that there are few design restrictions and it is easy to manufacture.

[Second Embodiment] FIGS. 9A and 9B are views showing a second embodiment of the present invention.
(A) is a perspective view of an ultrasonic elliptical oscillator, (b) is a top view of the same oscillator. The same parts as those of the ultrasonic elliptical oscillator shown in FIG. 1 are designated by the same reference numerals, and detailed description thereof will be omitted. The present embodiment is different from the first embodiment in that another pair of piezoelectric elements 51 having the same structure as the pair of piezoelectric elements 22a and 22b.
This is the point where (51a, 51b) is bonded to the other two side faces of the piezoelectric laminate. Of the electrodes of the piezoelectric elements 51a, 51b,
One is connected to the terminal B ′ via a voltage applying lead wire, and the other is grounded via a grounding lead wire.

FIG. 10 is a diagram showing a configuration of a circuit for vibrating the oscillator 50. The output from the phase shifter 31 is branched into two, and the power amplifiers 32 and 32 'are connected to each other so that power amplification is possible. The power amplifier 32 is connected to the terminal B, and the power amplifier 32 'is connected to the terminal B'. Thus, the alternating current having the frequency f from the alternating-current power supply 30 is shifted to the required phase shift (0
~ 360 °), the power is amplified by the power amplifiers 32, 32 ', and the piezoelectric elements 22a, 22b and
It is applied to 51a and 51b.

FIG. 11 is a perspective view showing the vibrator 50 and the slider 52 shown in FIG. When a voltage is applied to the terminal A, longitudinal vibration as shown in FIG. 3A occurs in the vibrator 50 in the Z-axis direction shown in FIG. Further, when a voltage is applied to the terminal B, bending vibration as shown in FIG. 3 (b) occurs in the vibrator 50 in the X-axis direction shown in FIG. When a voltage is further applied to the terminal B ′, bending vibration as shown in FIG. 3B occurs in the vibrator 50 in the Y-axis direction shown in FIG.

The oscillator 50 of the present embodiment is characterized in that it can generate an elliptical locus motion that combines the above three vibrations, and that the surface including the elliptical locus is controlled to match an arbitrary surface including the Z axis. This is a possible point. For example, power amplifier 32 '
When the voltage of each of the power amplifiers 32 and 33 is set to a certain value and a voltage is applied to each terminal, the protruding portion 26 becomes
Trajectories as shown in FIGS. 4A to 4I are drawn in the XZ plane shown in the figure. In addition, the power amplifier 32
When the voltage of each of the power amplifiers 32 ', 33 is set to a certain value and a voltage is applied to each terminal, the protrusion 26 is
4 (a) to (i) in the YZ plane shown in FIG.
You will draw a locus as shown in. Therefore, the elliptical locus of the protrusion 26 can be made to coincide with any surface including the Z axis by appropriately adjusting the amplification degrees of the power amplifiers 32 and 32 '. As a result, the slider 52, which is pressed by the protrusion 26 with a predetermined force, can be moved in any direction in the XY plane. Except for the above points, the same operational effects as the first embodiment are obtained.

FIG. 12 and FIG. 13 are diagrams showing a modification of the second embodiment described above, which is a modification having the same purpose as the modification (FIGS. 6 and 7) of the first embodiment. Ie 12th
In the example shown in the figure, the piezoelectric elements 22a, 22b and 51a, 51b are mounted on the upper base 23 and the lower base of an area larger than the area of the laminated surface of the piezoelectric laminated member 25.
It is an example of being glued to bridge to 24. Further, the example of FIG. 13 is an example in which the lower base 24 is not a square pole and the piezoelectric elements 22a, 22b and 51a, 51b are bonded to the side surfaces thereof.

In the second embodiment described above, when the frequency f for driving each vibrator is matched with the longitudinal vibration frequency fe and the bending vibration frequency fb, the frequencies are in the audible range,
This oscillator becomes a noise source for people. Therefore, it is desirable to design the vibrator so that the frequencies fe and fb are in the ultrasonic range, that is, 20 kHz or higher.

The present invention is not limited to the above-described embodiments and modifications, and it goes without saying that various modifications can be made without departing from the spirit of the present invention.

[Effects of the Invention] According to the present invention, two types of vibrations can be excited in the whole vibrator, so that the shape of the vibrator itself can be reduced and a large vibration output can be obtained. In addition, since a piezoelectric laminate composed of laminated piezoelectric elements is used,
With respect to longitudinal vibration, large vibration can be obtained even when operated without resonance. As a result, it is not necessary to match the resonance frequencies of the two vibrations, and it is easy to manufacture. Further, since the ultrasonic oscillator according to the present invention has a prismatic shape, there is no wasted space, and the oscillator itself and hence the driving device can be made compact.

[Brief description of drawings]

FIGS. 1 (a) and (b) to FIGS. 8 (a) to (d) are views showing a first embodiment of the present invention, and FIGS. 1 (a) and (b) are perspective views of a vibrator and Top view, FIG. 2 is a configuration diagram of a drive circuit of the same oscillator, FIGS. 3 (a) and 3 (b) are schematic side views showing operation modes of the oscillator, and FIGS. Figure 3 (a)
FIG. 5 is a diagram showing a locus of a protrusion when the operation modes shown in (b) are combined, FIG. 5 is a diagram showing vertical and horizontal components of an elliptical locus, and FIG. 6 is a perspective view showing a modified example of the oscillator. 7 (a) and 7 (b) are perspective views showing other modified examples of the oscillator, and FIGS. 8 (a) to 8 (d) are diagrams showing the configuration of a driving device using the oscillator. 9 (a) (b) to 13 (a)
FIG. 9 (b) is a diagram showing a second embodiment of the present invention, FIGS. 9 (a) and 9 (b) are perspective views and a top view of the oscillator, and FIG. 10 is a configuration diagram of a drive circuit of the oscillator. FIG. 11 is a perspective view of a slider and a vibrator, FIG. 12 is a perspective view showing a modification of the vibrator, and FIGS. 13A and 13B are perspective views showing other modifications of the vibrator. is there. 14 to 17 are diagrams showing a conventional ultrasonic linear motor, FIG. 14 is a diagram showing a configuration of a conventional ultrasonic linear motor, and FIG. 15 is a traveling wave generated in an elastic body of the conventional example. FIG. 16 is a diagram showing the configuration of another conventional example,
FIG. 17 is a diagram showing the configuration of still another conventional example. 1,5,20,50 …… Transducer, 6,40,41,52 …… Slider, 21,22
a, 22b, 51a, 51b …… Piezoelectric element, 23 …… Upper base, 24 …… Lower base, 25 …… Piezoelectric laminated member, 26 …… Projection part, 30 …… AC power supply, 31 …… Phase shifter, 32, 32 ', 33 ... Power amplifier.

Claims (8)

[Claims] 1. A laminate of a plurality of rectangular plate-shaped piezoelectric elements, a square plate for output extraction arranged at one end, and a square plate for fixation arranged at the other end. Piezoelectric laminated body, two side surface rectangular plate-shaped piezoelectric elements joined to two opposing side surfaces parallel to the laminating direction of the piezoelectric laminated body through insulating members, the piezoelectric laminated body and the side surface rectangular body An ultrasonic transducer comprising: electric terminals respectively taken out from the plate-shaped piezoelectric element, wherein an alternating voltage is applied to the piezoelectric laminate to generate longitudinal vibration in the laminating direction on the whole of the transducer, and the two opposite electrodes are disposed. An alternating voltage is applied to each of the side surface rectangular plate-shaped piezoelectric elements so that each vibrates in an opposite phase to generate bending vibration in the entire vibrator,
An ultrasonic transducer that generates ultrasonic elliptical vibration at the position of the output extraction square plate by combining the longitudinal vibration and the bending vibration. 2. A plurality of rectangular plate-shaped piezoelectric elements, a rectangular plate arranged at one end and having a larger dimension in a direction orthogonal to the stacking direction than the rectangular plate-shaped piezoelectric elements, and the other end. And a square plate for fixing, which has a larger dimension in a direction orthogonal to the stacking direction than the square plate piezoelectric element and which is arranged in a rectangular portion, and square plates at both ends of the piezoelectric laminate are connected to each other. An ultrasonic transducer comprising: two side surface rectangular plate-shaped piezoelectric elements facing each other, and electric terminals respectively taken out from the piezoelectric laminate and the side surface rectangular plate-shaped piezoelectric element, A voltage is applied to the piezoelectric laminated body to generate longitudinal vibration in the laminating direction in the entire vibrator, and an alternating voltage is applied to the two facing side surface rectangular plate-shaped piezoelectric elements so that they vibrate in opposite phases. Flexural vibration is generated in the whole vibrator, An ultrasonic transducer that generates ultrasonic elliptical vibration at the position of the output extraction square plate by combining the longitudinal vibration and the bending vibration. 3. A laminate of a plurality of rectangular plate-shaped piezoelectric elements, a rectangular plate for output extraction arranged at one end, and a rectangular plate for fixation arranged at the other end. PIEZOELECTRIC LAMINATE, TWO SIDE FACE SQUARE PLATE PIEZOELECTRIC ELEMENTS BONDED ON TWO SIDE FACES OF A SQUARE PLATE FOR FIXING THE PIEZOELECTRIC LAMINATE OR SQUARE PLATE FOR OUTPUT OUTPUT An ultrasonic transducer comprising: an electric terminal respectively taken out from a plate-shaped piezoelectric element, wherein a voltage is applied to the piezoelectric laminated body to generate longitudinal vibration in a laminating direction in the entire transducer, and two opposing two By applying an alternating voltage to each of the side surface rectangular plate-shaped piezoelectric electrons so as to vibrate in opposite phases to generate bending vibration in the entire vibrator, and by synthesizing the longitudinal vibration and the bending vibration, The ultrasonic elliptical vibration is emitted at the position of the square plate for extracting the output. Ultrasonic transducer to produce. 4. A laminate of a plurality of rectangular plate-shaped piezoelectric elements, a square plate for output extraction arranged at one end, and a square plate for fixation arranged at the other end. A piezoelectric laminated body; four side surface rectangular plate-shaped piezoelectric elements joined to four side surfaces parallel to the laminating direction of the piezoelectric laminated body via insulating members; An ultrasonic vibrator having: an electric terminal that is respectively taken out, wherein a voltage is applied to the piezoelectric laminated body to generate longitudinal vibration in a laminating direction on the entire vibrator, and the first facing side rectangular plate An alternating voltage is applied to each piezoelectric element so that each vibrates in an opposite phase to generate a first bending vibration in the entire vibrator, and each of the second opposing side surface rectangular plate piezoelectric elements has an opposite voltage. An alternating voltage is applied as if it oscillates in phase, and A second bending vibration that is orthogonal to the first bending vibration is generated, and the longitudinal vibration, the first bending vibration, and the second bending vibration are combined to obtain the position of the square plate for extracting the output. 2. An ultrasonic transducer for generating ultrasonic elliptical vibration in a plane in any direction including the stacking direction. 5. A plurality of rectangular plate-shaped piezoelectric elements, a rectangular plate for output extraction which is arranged at one end and has a larger dimension in a direction orthogonal to the stacking direction than the rectangular plate-shaped piezoelectric elements, and the other end. And a square plate for fixing, which has a larger dimension in a direction orthogonal to the stacking direction than the square plate piezoelectric element and which is arranged in a rectangular portion, and square plates at both ends of the piezoelectric laminate are connected to each other. An ultrasonic transducer comprising: four side-surface rectangular plate-shaped piezoelectric elements bonded together as described above; and electric terminals respectively taken out from the piezoelectric laminate and the side-surface rectangular plate-shaped piezoelectric element, wherein the piezoelectric laminated body By applying a voltage to the body, longitudinal vibration in the stacking direction is generated in the whole vibrator, and an alternating voltage is applied to the first facing side surface rectangular plate piezoelectric elements so that they vibrate in opposite phases. The first bending vibration is generated on the entire child, An alternating voltage is applied to the two facing side surface rectangular plate-shaped piezoelectric elements so that the piezoelectric elements vibrate in opposite phases, and a second bending vibration orthogonal to the first bending vibration is generated in the entire vibrator, By synthesizing the longitudinal vibration, the first bending vibration, and the second bending vibration, ultrasonic elliptical vibration is generated in a plane in any direction including the stacking direction at the position of the square plate for extracting the output. An ultrasonic transducer that generates. 6. A laminate of a plurality of rectangular plate-shaped piezoelectric elements, a square plate for output extraction arranged at one end, and a square plate for fixation arranged at the other end. Piezoelectric laminate, four side surface rectangular plate-shaped piezoelectric elements joined to four side surfaces of a square plate for fixing the piezoelectric laminate or a square plate for extracting output, the piezoelectric laminate and the side plate An ultrasonic transducer comprising: electric terminals respectively taken out from the piezoelectric element, wherein a voltage is applied to the piezoelectric laminated body to generate longitudinal vibration in a laminating direction over the entire transducer, An alternating voltage is applied to the side surface rectangular plate-shaped piezoelectric elements so that the piezoelectric elements vibrate in opposite phases, and a first bending vibration is generated in the ultrasonic vibrator over the entire vibrator, and the second opposed side surface rectangular plate. An alternating voltage is applied to the piezoelectric elements as they vibrate in opposite phases. Is applied to generate a second bending vibration orthogonal to the first bending vibration in the entire vibrator, and the longitudinal vibration, the first bending vibration, and the second bending vibration are combined. An ultrasonic transducer that generates ultrasonic elliptical vibration in a plane in any direction including the stacking direction at the position of the output extraction square plate. 7. The ultrasonic vibrator according to claim 1, 2 or 3, and a movable member that comes into contact with a square plate for taking out an output of the ultrasonic vibrator, and the movable member is moved in a linear direction. A drive device characterized in that 8. The ultrasonic vibrator according to claim 4, 5 or 6, and a movable member that comes into contact with a square plate for taking out an output of the ultrasonic vibrator, and the movable member is within a plane. A drive device configured to be moved in the direction of.