JPH09121571A - Ultrasonic vibrator and ultrasonic linear motor or ultrasonic motor using it - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the starting torque and thrust of an ultrasonic linear motor or ultrasonic motor by constituting a laminated piezoelectric element of a piezoelectric element having a specific mechanical quality factor. SOLUTION: The piezoelectric element used for a laminated piezoelectric element 12 is constituted by piling up several tens or hundreds of so-called hard type PZT piezoelectric elements having a size of 2mm×3.1mm×9mm. Each single plate 18 constituting the element 12 is provided with an electrode 19. In addition, insulating sections 17 of about 0.5-0.1mm are provided at three locations at the end section of the single plate 18 and, only at one end section, the electrode 19 is provided to the side edge. A piezoelectric ceramic having a mechanical quality factor (Qm) of >=500 (when 1 Vp-p is measured) is used for forming the single plate 18. The element 12 is constituted by piling the single plates 18 upon another so that their directions of polarization can alternately become opposite to each other.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrasonic vibrator, an ultrasonic linear motor using the ultrasonic vibrator, and an ultrasonic motor.

[0002]

2. Description of the Related Art In recent years, an ultrasonic motor has attracted attention as a new motor replacing an electromagnetic motor. This ultrasonic motor has the following advantages over a conventional electromagnetic motor.

(1) Low rotation and high torque can be obtained without gears. (2) Large holding force. (3) High resolution. (4) It is extremely quiet. (5) Magnetic noise is not generated, and the influence of noise is not exerted.

As a conventional ultrasonic linear motor, there is an ultrasonic linear motor disclosed in Japanese Patent Laid-Open No. 6-105571 proposed by the present applicant. A conventional ultrasonic transducer and ultrasonic linear motor will be described below based on Japanese Patent Laid-Open No. 6-105571.

The conventional ultrasonic transducer 10 disclosed in the publication.
As shown in FIG. 16, 0 is a rectangular parallelepiped basic elastic body 1
11 and two laminated piezoelectric elements 113 disposed on the upper part of the basic elastic body 111 and located at a portion substantially corresponding to the antinode of the secondary resonant bending vibration.

Then, the holding elastic member 112 fixes the two laminated piezoelectric elements 113 to the basic elastic body 111. That is, although not shown, the basic elastic body 11
1 has three tapped screws, and the holding elastic body 112 is fixed to the basic elastic body 111 by screws 114. At this time, the laminated piezoelectric element 113 is held by abutting by the holding elastic body 112.

Multilayer piezoelectric element 1 of the basic elastic body 111
The sliding member 116 is made of an epoxy-based material at a portion of the surface opposite to the surface on which 13 is distributed (the surface on the side in contact with the driven body) substantially corresponding to the antinode of the secondary resonance bending vibration. It is joined using the adhesive of. The sliding member 116 is formed by mixing polyimide with carbon fiber as a filler and mica as a filler (carbon fiber: 20).
% By weight, 30% by weight mica).

Next, the operation of this ultrasonic transducer 100 will be described. By properly setting the dimensions of the ultrasonic transducer 100, the primary resonant longitudinal vibration and the secondary resonant bending vibration can be excited at substantially the same frequency.

In FIG. 16, the laminated piezoelectric element 11 on the left side is shown.
The electric terminals taken out from No. 3 are A and G (referred to as A phase) terminals, and the electric terminals taken out from the laminated piezoelectric element 113 on the right side are called B and G (referred to as B phase) terminals. First, a DC voltage of 30 V is applied to the A phase and the B phase. By doing so, a compressive force (preload) can be applied to the laminated piezoelectric element 113.

Therefore, the phase A has an amplitude of 10 Vp at the frequency Fr.
When the alternating voltage of −p is applied and the alternating voltage of the same frequency and the same amplitude and the same phase is applied to the B phase, the primary resonant longitudinal vibration can be excited. Next, in the A phase, the amplitude is 10 Vp− at the frequency Fr.
When an alternating voltage of p is applied and an alternating voltage of the same frequency and the same amplitude and opposite phase is applied to the B phase, secondary resonant bending vibration can be excited.

Further, when an alternating voltage having an amplitude of 10 Vp-p with a frequency Fr is applied to the A-phase and the B-phase and the phase difference is set to 90 degrees or -90 degrees, the sliding member 116 is rotated clockwise or counterclockwise. Clockwise ultrasonic elliptical vibration can be excited.

Next, the operation of the ultrasonic linear motor will be described. As described above, A of the ultrasonic transducer 100
Frequency Fr, amplitude 10Vp-p, phase difference +9 for phase B and phase B
An alternating voltage of 0 degree or -90 degree is applied. Then, since ultrasonic elliptical vibration is generated in the sliding member 116 of the ultrasonic transducer 100, the driven member (not shown) is moved to the sliding member 11.
When it is pressed by 6, the drive body is driven left and right. The characteristics of the linear motor are as follows: no-load speed 150 mm / s
ec and a starting thrust of 2N were obtained.

[0013]

However, the ultrasonic linear motor described in Japanese Patent Laid-Open No. 6-105571 has the following problems. That is, as the laminated piezoelectric element 113, a commercially available laminated piezoelectric element is used, and the mechanical quality factor of each piezoelectric element that is a component is 1
It was less than 00. This is because the conventional laminated piezoelectric element often uses its displacement and is made of a so-called soft material. Therefore, the ultrasonic transducer 100 using the laminated piezoelectric music piece also has a low mechanical quality factor. If the mechanical quality factor is low, even if the same energy is input to the ultrasonic transducer 100, the vibration displacement,
Or the generated power becomes small. As a result, there has been a problem that the speed and thrust of the ultrasonic motor cannot be taken out sufficiently.

Therefore, the present invention provides an ultrasonic transducer having a large mechanical quality factor and a large vibration displacement or generated force, and an ultrasonic linear motor and an ultrasonic motor having a sufficiently large starting torque and thrust by using the ultrasonic transducer. It is provided.

[0015]

According to the first aspect of the present invention,
At least an elastic body and at least two laminated piezoelectric elements held by a part of the elastic body, and by applying alternating voltages having different phases to the laminated piezoelectric element, ultrasonic elliptical vibration is generated. An ultrasonic transducer for excitation, wherein the laminated piezoelectric element is composed of a piezoelectric element having a mechanical quality factor of 500 or more.

An ultrasonic linear motor according to a second aspect of the present invention uses an elastic body and at least two piezoelectric elements held by a part of the elastic body and having a mechanical quality factor of 500 or more. An ultrasonic oscillator including at least a laminated piezoelectric element, and a driven member that is pressed against an end surface of the laminated piezoelectric element in the ultrasonic oscillator, and apply alternating voltages having different phases to the laminated piezoelectric element. By applying, an elliptical ultrasonic vibration is excited in the elastic body to drive the driven member in a direction along the elastic body.

According to a third aspect of the present invention, there is provided an ultrasonic motor in which a laminated piezoelectric element using an elastic body and at least two piezoelectric elements held by a part of the elastic body and having a mechanical quality factor of 500 or more. An ultrasonic transducer including at least an element,
A circular driven member, which is pressed against the end face of the laminated piezoelectric element in the ultrasonic transducer, applies an alternating voltage having a different phase to the laminated piezoelectric element to form an ultrasonic ellipse on the elastic body. It is characterized in that the driven member is rotationally driven by exciting vibration.

According to the ultrasonic transducer of the first aspect, alternating voltages having a phase difference of 90 degrees are applied to at least two laminated piezoelectric elements which are constituent elements, and the first vibration mode and the second vibration are applied. The modes are simultaneously excited to generate ultrasonic elliptical vibration in the elastic body. In this case, since the laminated piezoelectric element of the ultrasonic group oscillator is made of a material having a mechanical quality factor of 500 or more, the ultrasonic oscillator itself has a mechanical quality factor of 50.
It is possible to excite large ultrasonic elliptical vibrations even if the magnitude of the alternating voltage applied to the laminated piezoelectric element is relatively low.

According to the second aspect of the invention, by using the ultrasonic transducer, it is possible to realize an ultrasonic linear motor having a large thrust and a large speed.

According to the third aspect of the present invention, by using the ultrasonic vibrator, it is possible to realize an ultrasonic motor having a large starting torque and good motor characteristics such as no-load rotation speed.

[0021]

Embodiments of the present invention will be described below.

(Embodiment 1) An ultrasonic transducer 10 according to Embodiment 1 will be described with reference to FIG. Show this super. The ultrasonic oscillator 10 includes a basic elastic body 11 made of a brass material formed in a convex shape. The dimensions of the basic elastic body 11 are 30 mm in width and 4 in depth, excluding the convex portions.
mm and height 7.5 mm. The width of the convex part is 4m
m, depth 4 mm, height 2, 5 mm.

A pin 16 made of a stainless steel material having a diameter of 2 mm is driven by press fitting at the center of the basic elastic body 11 in the width direction and at a position 6 mm from the bottom surface.

Next, the laminated piezoelectric element 12 will be described. The piezoelectric element used in this laminated piezoelectric element 12 is
This is a so-called hard PZT piezoelectric element. This PZT
It is a stack of several tens to several hundreds of piezoelectric elements, and the dimensions are 2 mm × 3. It is 1 mm × 9 mm.

The structure of the laminated piezoelectric element 12 used in the first embodiment is shown in FIGS. FIG. 2 is an exploded view of the laminated piezoelectric element 12, which is seen from the front side, and FIG. 3 is what is seen from the back side.

As shown in FIGS. 2 and 3, the single plate 18 constituting the laminated piezoelectric element 12 is provided with an electrode 19. Further, 0.5 to 0.
An insulating portion 17 of about 1 mm is provided, and an electrode 19 is provided up to the edge only at one end.

In the first embodiment, the piezoelectric ceramics as a material of the single plate 18 has a thickness of 0.1 mm, an electromechanical coupling coefficient (k33) of 0.6 to 0.7 (at the time of measuring 1 Vp-p), Mechanical quality factor (Qm) 75, 500, 100
0, 1500 (at the time of LVp-p measurement) was used. FIG. 4 shows a laminated piezoelectric element 12 in which these layers are laminated so that their polarizations P are alternately reversed.

The laminated piezoelectric element 12 was laminated by the integral firing method. External electrodes 91 are provided on the right side surface and the left side surface of the laminated piezoelectric element 12 as shown in FIG. 4, and the electric terminals 92 and 93 are taken out.

The surface of the laminated piezoelectric element 12 in which the internal electrodes are not exposed is brought into contact with the surface of the basic elastic body 11, and the end portion of the laminated piezoelectric element 12 is held by the elastic elastic member 13 for holding. Fix with. As shown in FIG. 1, electric terminals taken out from the laminated piezoelectric element 12 on the left side are A, GND (A
Phase), and the electric terminals taken out from the laminated piezoelectric element 12 on the right side are B and GND (referred to as B phase).

A position 9 mm (vibration of resonance bending vibration) from both ends of the surface of the basic elastic body 11 opposite to the surface on which the laminated piezoelectric element 12 is disposed (the surface in contact with the driven body). Rectangular shape (dimension 3) at two locations where the amplitude shows the maximum value)
A driver element 15 (grinding stone material: resin in which abrasive grains of alumina are dispersed) having a size of 4 mm, a depth of 4 mm, and a thickness of 1 mm is joined by using an epoxy adhesive.

Next, the details of the method of assembling the ultrasonic transducer 10 will be described. As shown in FIG. 1, the basic elastic body 1
The laminated piezoelectric elements 12 are arranged on both sides of the convex portion 1. Then, the holding elastic member 13 (width 4 mm, depth 4 mm, height 2.5 mm) is fixed on the basic elastic body 11. Although not shown, the basic elastic body 11 is tapped with screws at two positions, and the holding elastic body 13 is fixed to the basic elastic body 11 by two screws 14 as shown in FIG. At this time,
The laminated piezoelectric element 12 has a compressive force (5 kgf to 50 kgf) between the convex portion of the basic elastic body 11 and the holding elastic body 13.
It is held and fixed in the state of applying.

Further, the laminated piezoelectric element 12 is fixed to the convex portion of the basic elastic body 11 and the holding elastic body 13 with an epoxy adhesive. The side surface portion of the laminated piezoelectric element 12 that is in contact with the basic elastic body 11 and the basic elastic body 11 are also adhered using an epoxy resin finger. Further, the contacting portions of the holding elastic body 13 and the basic elastic body 11 are also joined by an epoxy adhesive. After that, the driver element 1 is formed on the surface of the basic elastic body 11 opposite to the surface on which the laminated piezoelectric element 12 is arranged.
5 are joined using an epoxy adhesive.

Next, the operation of the ultrasonic transducer 10 will be described. If the ultrasonic transducer 10 is formed in the above-described size and shape, when the alternating voltage applied to the A phase and the alternating voltage applied to the B sum are applied with the same amplitude and the same phase, the maximum length direction The first resonance longitudinal vibration of is resonance frequency 55
It could be excited at kHz.

On the other hand, when the alternating voltage applied to the A phase and the alternating voltage applied to the B phase are applied with the same amplitude and opposite phase,
In-plane secondary resonance bending vibration having the maximum area could be excited at a resonance frequency of 55 kHz. Ultrasonic transducer 1 at this time
The vibration state of 0 is shown in FIGS. FIG. 5 shows the case of the primary resonant longitudinal vibration, and FIG. 6 shows the case of the secondary resonant bending vibration. The examples shown in FIG. 5 and FIG. 6 are analyzed by simulation using the finite element method, but it was confirmed that such vibration actually occurred.

When an alternating voltage having a resonance frequency of 55 kHz, an amplitude of 10 Vp-p and a phase difference of ± 90 degrees is applied to the A and B phases, a clockwise or counterclockwise ultrasonic elliptical vibration can be excited at the position of the driver 15. It was At this time, the electromechanical quality factor of the piezoelectric element forming the laminated piezoelectric element 12 is 500, 100.
In the case of using 0, 1500, the mechanical quality factor is 500 or more and the elliptical vibration amplitude is several μmp.
-P. However, in the ultrasonic transducer 12 constituted by the laminated piezoelectric element 12 using a piezoelectric element having an electromechanical quality factor of 75, the mechanical quality factor is 20.
It was about 0 and the elliptical vibration amplitude was 1 μmp-p or less.

(Structure of Ultrasonic Linear Motor) Next, referring to FIG.
An ultrasonic linear motor using the ultrasonic transducer 10 will be described with reference to FIG. As shown in FIG. 7, the ultrasonic transducer 10 is held from both sides by the two holding plates 21 at the pin 16 portion thereof. The holding plate 21 is provided with a hole having substantially the same diameter as the diameter of the pin 16, and the hole and the pin 16 are engaged with each other. By holding the ultrasonic vibrator 10 in this manner, the ultrasonic vibrator 10 is held.
Has a degree of freedom only for rotation about the pin 16.

The holding plate 21 is fixed to the holding plate fixing member 22 with screws 23. A pair of linear bushes 24 are erected on the holding plate fixing member 22. The linear bush 24 moves linearly (up and down in FIG. 7) along the axis 25. Further, the shaft 25 is a shaft fixing member 26.
The shaft fixing member 26 is fixed to the base 27 with screws 35.

A tap is cut in the substantially central portion of the shaft fixing member 26 so that the pressing screw 28 can be screwed. A spring 29 is inserted between the pressing screw 28 and the holding plate fixing member 22.

The fixing portion 30 of the cross roller guide is fixed to the base 27 with screws 31.
A sliding member holding portion 33 is fixed to the moving portion 32 of the cross roller guide by screws (not shown), and zirconia ceramics is bonded to the sliding member holding portion 33 as a sliding member 34. With such a configuration, by adjusting the pressing screw 28, the sliding member 34 of the ultrasonic transducer 10 is adjusted.
The pressing force applied to the (driven member) can be adjusted.

(Operation of Ultrasonic Linear Motor) Next, the operation of the ultrasonic linear motor of the first embodiment will be described. As described above, the frequency Fr, the amplitude 10 Vp-p, and the phase difference +90 degrees or − are added to the A phase and the B phase of the ultrasonic transducer 10.
An alternating voltage of 90 degrees is applied. Then, the sliding member 34 is driven rightward or leftward. At this time, when the electromechanical quality factor of the piezoelectric element in the laminated piezoelectric element 12 of the ultrasonic transducer 10 is 500, 1000, 1500, the starting thrust of the ultrasonic linear motor is 8 N and the no-load speed is 300 mm / sec. Was given. However, in the case of the ultrasonic transducer 10 using the laminated piezoelectric element 12 in which the electromechanical quality factor of the piezoelectric element is 75, the starting thrust of the ultrasonic linear motor is 2N and the no-load speed is 15N.
It was 0 mm / sec.

According to the first embodiment, since the laminated piezoelectric element 12 is composed of a piezoelectric element having a large mechanical quality factor, the ultrasonic transducer 1 using the laminated piezoelectric element 12
The mechanical quality factor of 0 becomes large, so that a large elliptical vibration can be excited in the ultrasonic transducer 10. As a result, it was possible to improve linear motor characteristics such as starting thrust and no-load speed.

(Second Embodiment) A second embodiment will be described with reference to FIGS.

(Structure of Ultrasonic Transducer) FIG. 8 shows a plan view of the ultrasonic oscillator 50 of the second embodiment, and FIG. 9 shows α of FIG.
10 shows a front view of the ultrasonic transducer 50 viewed from the direction shown in FIG.
8 shows a rear view of the ultrasonic transducer 50 seen from the β direction in FIG. 8, FIG. 11 shows a right side view of the ultrasonic transducer 50 seen from the γ direction in FIG. 8, and FIG. It is a left side view of ultrasonic transducer 50 seen from the direction.

The ultrasonic transducer 50 shown in FIGS. 8 to 12
Includes a prismatic basic elastic body 51 made of a brass material (O material of C2801P). This basic elastic body 51
Has a size of approximately 7 mm × 9 mm × 35 mm, and a groove 52 having a depth of 1 to 2 mm is provided over the entire circumference at a position 11 mm from the lower end thereof.

Further, the laminated piezoelectric element 53 is held on the front surface and the back surface of the basic elastic body 51 with a constant inclination angle. As the laminated piezoelectric element 53 used here, the one described in Embodiment 1 with reference to FIGS. 2 and 3 was used. The electric terminals output from the respective laminated piezoelectric elements 53 are referred to as A, GND, B, and GND, respectively. The laminated piezoelectric element 53 is held and fixed by a holding elastic body 54 in a state where a compressive stress is applied.

The laminated piezoelectric element 53 is composed of the basic elastic body 5
The front and back surfaces of the unit 1 are mounted so as to be tilted in the opposite directions when facing each other. To the tip of the basic elastic body 51, a sliding driving element 55 made of a grindstone in which abrasive grains of alumina ceramic are dispersed in an annular phenol resin is joined. A through hole 59 is provided along the lengthwise direction in the central portion of the basic elastic body 51, and a tap 60 is cut in a part of the through hole 59 (correctly, a node amount of longitudinal vibration).

A method of producing the ultrasonic transducer 50 will be described with reference to FIGS. 8 to 13. Multilayer piezoelectric element 5
3 is inserted into a recess 58 provided in the basic elastic body 51.
The holding elastic body 54 has a protrusion 57 provided on the basic elastic body 51.
Is inserted while being guided along the laminated piezoelectric element 53.
After being abutted against, the resin is fixed to all the screws and abutting surfaces with an epoxy adhesive under the condition that a compressive stress of 100 N is applied.

(Operation of Ultrasonic Transducer) Next, the operation of the ultrasonic transducer 50 will be described. The ultrasonic transducer has a primary resonant longitudinal vibration (vertical vibration in FIG. 9) and a primary (secondary considering the twist below the groove 52) resonant torsional vibration (longitudinal vibration). Vibration having a vibration direction as a twist axis can be excited at substantially the same frequency Fr (40 kHz). Further, the shape is such that there is no natural vibration of bending resonance vibration in the vicinity of this frequency.

First, an amplitude of 20 at the frequency Fr is applied to the A terminal.
When an alternating voltage of Vp-p was applied and an alternating voltage of the same frequency and the same amplitude and the same phase was applied to the B terminal, resonance longitudinal vibration could be excited. The node portion of the resonance longitudinal vibration exists at a substantially central position on the central axis of the basic elastic body 51.

Next, an amplitude of 20 Vp at the frequency Fr is applied to the A terminal.
When an alternating voltage of -p was applied and an alternating voltage of the same frequency, same amplitude and opposite phase was applied to the B terminal, resonance torsional vibration could be excited. In the resonance torsional vibration, all the central axes of the basic elastic body 51 are nodes.

Next, an amplitude of 20 Vp at the frequency Fr is applied to the A terminal.
When an alternating voltage of −p is applied and an alternating voltage having the same frequency and the same amplitude but different phase by 90 degrees is applied to the B terminal, the resonant longitudinal vibration and the resonant torsional vibration are combined, and the sliding driving element 55.
Elliptical vibration could be excited at the position. At this time, in the ultrasonic transducer 50 using the laminated piezoelectric element 53 using the electromechanical quality coefficient of the piezoelectric element of 500, 1000, 1500, the mechanical quality coefficient is 500 or more, and the elliptic vibration The amplitude was 5 to 6 μmp-p.

However, the electromechanical quality factor of the piezoelectric element is 7
In the ultrasonic vibrator 50 using the laminated piezoelectric element 53 of No. 5, the mechanical quality factor was about 200, and the elliptical vibration amplitude was about 2 μmp-p or less.

(Structure and Operation of Ultrasonic Motor) Next, referring to FIG.
An ultrasonic motor 70 using the ultrasonic transducer 50 will be described with reference to FIGS. 14 is a front view of the ultrasonic motor 70, and FIG. 15 is an exploded view of the ultrasonic motor 70.

A shaft 71 is provided in the through hole 59 of the ultrasonic transducer 50.
Is inserted. As shown in FIG. 15, the shaft 71 is provided with screw portions 72a and 72b at its central portion and both end portions,
The screw portion 72a at the center is the tap portion 6 of the ultrasonic transducer 50.
It is glued and fixed to 0. An annular rotor 73 is pressed and fixed to the upper end of the ultrasonic transducer 50 by a spring 76 via a thrust bearing 74 and a spring holder 75.

The pressing force of the rotor 73 against the ultrasonic transducer 50 is adjusted by the nut 77. On the lower surface of the rotor 73, a sliding member 78 made of an annular zirconia ceramic is adhered. When the ultrasonic motor 70 is fixed, the shaft 71 projecting from the lower portion thereof may be screwed and fixed to a base (not shown).

As described above, an alternating voltage having a frequency of 40 kHz, an amplitude of 20 Vp-p, and a phase difference of +90 degrees or -90 degrees is applied to the A and B terminals of the ultrasonic transducer 50. Then, the rotor 73 rotates clockwise or counterclockwise.
At this time, the electromechanical quality factor of the piezoelectric element is 500, 100.
In the case of the ultrasonic transducer 50 using the laminated piezoelectric element 53 of 0, 1500, the starting torque of the ultrasonic motor 70 was 500 g-cm and the no-load rotation speed was 120 rpm. However, in the case of the ultrasonic transducer 50 using the laminated piezoelectric element 53 using the piezoelectric element having an electromechanical quality factor of 75, the ultrasonic motor 70
The starting torque was 200 g-cm, and the no-load rotation speed was 80 rpm.

According to the second embodiment, since the laminated piezoelectric element 53 is composed of a piezoelectric element having a large mechanical quality factor, the ultrasonic vibrator 5 using the laminated piezoelectric element 53 is not limited to the piezoelectric element 53.
The mechanical quality factor of 0 becomes large, so that a large elliptical vibration can be excited in the ultrasonic transducer 50. As a result, the motor characteristics such as the starting torque and the no-load rotation speed could be improved.

In the second embodiment, the basic elastic body 51
However, the cylindrical piezoelectric element 53 may be partially cut to fix the laminated piezoelectric element 53. Further, in the present embodiment, 2 has shown the example in which the two laminated piezoelectric elements 53 are used, but a four-element configuration in which they are attached to the four side surfaces of the basic elastic body 51 may be adopted.

[0059]

According to the present invention described in detail above, the following effects can be obtained.

According to the invention described in claim 1, the ultrasonic transducer itself has a mechanical quality factor of 500 or more,
Accordingly, it is possible to provide an ultrasonic transducer capable of exciting a large ultrasonic elliptical vibration even if the magnitude of the alternating voltage applied to the laminated piezoelectric element is relatively low.

According to the second aspect of the present invention, by using the ultrasonic vibrator, it is possible to provide an ultrasonic linear motor having a large thrust and a large speed.

According to the third aspect of the invention, by using the ultrasonic vibrator, it is possible to provide an ultrasonic motor having a large starting torque and good motor characteristics such as no-load rotation speed.

[Brief description of the drawings]

FIG. 1 is a perspective view illustrating an ultrasonic transducer according to a first embodiment of the present invention.

FIG. 2 is an exploded perspective view of the laminated piezoelectric element according to the first embodiment of the present invention.

FIG. 3 is an exploded perspective view of the laminated piezoelectric element according to the first embodiment of the present invention.

FIG. 4 is a perspective view of the laminated piezoelectric element according to the first embodiment of the present invention.

FIG. 5 is an explanatory diagram showing a state of longitudinal vibration of the ultrasonic transducer according to the first embodiment of the present invention.

FIG. 6 is an explanatory diagram showing a torsional vibration state of the ultrasonic transducer according to the first embodiment of the present invention.

FIG. 7 is a front view showing the ultrasonic linear motor according to the first embodiment of the present invention.

FIG. 8 is a plan view showing an ultrasonic transducer according to a second embodiment of the present invention.

FIG. 9 is a front view showing an ultrasonic transducer according to a second embodiment of the present invention.

FIG. 10 is a rear view showing the ultrasonic transducer according to the second embodiment of the present invention.

FIG. 11 is a right side view showing the ultrasonic transducer according to the second embodiment of the present invention.

FIG. 12 is a left side view showing the ultrasonic transducer according to the second embodiment of the present invention.

FIG. 13 is an exploded view showing an ultrasonic transducer according to a second embodiment of the present invention.

FIG. 14 is a front view showing an ultrasonic motor according to a second embodiment of the present invention.

FIG. 15 is an exploded view showing an ultrasonic motor according to a second embodiment of the present invention.

FIG. 16 is a front view showing a conventional ultrasonic transducer.

[Explanation of symbols]

 10 Ultrasonic Transducer 11 Basic Elastic Body 12 Laminated Piezoelectric Element 13 Holding Elastic Body 15 Driver 16 Pin 21 Holding Plate 32 Moving Part 34 Sliding Member 50 Ultrasonic Transducer 51 Basic Elastic Body 52 Groove 53 Laminated Piezoelectric Element 55 Sliding driver 59 Through hole 70 Ultrasonic motor 73 Rotor

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yoshihisa Taniguchi 2-43-2 Hatagaya, Shibuya-ku, Tokyo Inside Olympus Optical Co., Ltd.

Claims (3)

[Claims] 1. An elastic body and at least two laminated piezoelectric elements held by a part of the elastic body, wherein alternating voltages having different phases are applied to the laminated piezoelectric element, An ultrasonic transducer for exciting ultrasonic elliptical vibration, wherein the laminated piezoelectric element is constituted by a piezoelectric element having a mechanical quality factor of 500 or more. 2. An ultrasonic transducer comprising at least an elastic body and a laminated piezoelectric element using at least two piezoelectric elements having a mechanical quality factor of 500 or more and held by a part of the elastic body, The ultrasonic transducer includes a driven member pressed against the end surface of the laminated piezoelectric element, and by applying alternating voltages having different phases to the laminated piezoelectric element, ultrasonic elliptical vibration is generated in the elastic body. An ultrasonic linear motor, which is excited to drive the driven member in a direction along an elastic body. 3. An ultrasonic transducer comprising at least an elastic body and a laminated piezoelectric element using at least two piezoelectric elements having a mechanical quality factor of 500 or more and held by a part of the elastic body, The ultrasonic transducer includes a circular driven member that is pressed against the end surface of the laminated piezoelectric element, and by applying alternating voltages having different phases to the laminated piezoelectric element, an ultrasonic ellipse is applied to the elastic body. An ultrasonic motor characterized in that vibration is excited to rotationally drive the driven member.