JPH11346486A - Ultrasonic motor and electronic apparatus equipped with the ultrasonic motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To generate large torque and to stabilize the torque. SOLUTION: An ultrasonic motor 10 for taking out an output, through press contact with a piezoelectric oscillator 11 performing elliptical oscillation by combining bending oscillation and stretching oscillation comprises a member for pressing the piezoelectric oscillator 11, at a part opposite to the press contact part, against the press contact part, and a member 14 for guiding the piezoelectric oscillator 11 in the pressing direction at least one node of the bending oscillation or stretching oscillation of the piezoelectric oscillator 11, while abutting against the opposite sides in at least two directions, i.e., the pressing direction and a direction perpendicular thereto.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrasonic motor that generates a large torque and stabilizes the torque, and an electronic device with the ultrasonic motor.

[0002]

2. Description of the Related Art In recent years, in the field of micromotors, ultrasonic motors utilizing the piezoelectric effect of piezoelectric elements have the advantages of high conversion efficiency from electrical energy to mechanical energy and miniaturization of the device configuration. Attention has been paid. Especially,
An ultrasonic motor of a type that obtains a driving force by two-mode vibration of a piezoelectric vibrator itself is widely used from the viewpoint of miniaturization.

FIG. 14 shows the structure of an ultrasonic motor according to the prior art. The ultrasonic motor 100 is a piezoelectric vibrator 1 that performs a predetermined polarization process to generate bending vibration and expansion / contraction vibration.
01, a supporting member 102 which is a central portion of the piezoelectric vibrator 101 and supports the nodes of the bending vibration and the stretching vibration, and a pressing member 103 fixed to a peripheral edge of the supporting member 102; A moving body 104 is pressed against an end face of the moving body 101. Then, the piezoelectric vibrator 101 simultaneously excites the bending vibration and the expansion / contraction vibration and performs an elliptical vibration on the peripheral surface, while the pressing force is applied to the central portion of the piezoelectric vibrator 101 via the pressing member 103 and the supporting member 102. , The piezoelectric vibrator 101 and the moving body 104 are periodically pressed into contact with each other to generate a frictional force therebetween. Then, the moving body 104 is rotated in one direction, and the contact position between the press-contact portion and the moving body 104 also changes. In addition, since the pressing force is applied to half of the piezoelectric vibrator from the center (support position) to the press-contact portion, the balance of vibration is lost on the left and right of the center of the piezoelectric vibrator, the vibration efficiency is reduced, and the position of the node is also shifted from the center. Therefore, the vibration loss at the support part also becomes severe.

[0004]

However, since the supporting member 102 of the ultrasonic motor according to the prior art merely holds the piezoelectric vibrator 101, the supporting position of the supporting member 102 is large when a large pressing force is applied. If it is, it will shift from the vibration node. Then, the bending vibration and the stretching vibration generated in the piezoelectric vibrator become unstable. Further, the piezoelectric vibrator 101
Receives the reaction force from the pressure contact portion with the moving body 104, and is displaced in the direction perpendicular to the pressing direction, and slides the pressure contact portion with the moving body 104, so that the piezoelectric vibrator 101 and the moving body 104 And the frictional force generated between them varies. The unstable vibration state and the fluctuation of the frictional force described above have caused a problem that a large torque cannot be generated and the torque fluctuates.

The present invention has been made to solve the above problems, and an object of the present invention is to provide an ultrasonic motor and an electronic device with an ultrasonic motor which generate a large torque and stabilize the torque and the moving speed. provide.

[0006]

In order to solve the above-mentioned problems, a means for solving the above-mentioned problem is that a piezoelectric vibrator that performs elliptical vibration by bending vibration and expansion-contraction vibration is brought into pressure contact with the piezoelectric vibrator to take out an output. In the acoustic wave motor, a pressing member that presses a portion of the piezoelectric vibrator opposite to the portion to be pressed against the pressed portion, and at least one node of the bending vibration or the expansion and contraction vibration of the piezoelectric vibrator. In at least two directions perpendicular to the pressing direction,
And a node guide member that contacts the opposing sides and guides the piezoelectric vibrator in the pressing direction.

In the above means, when the node guide member abuts on one side of the bending vibration or the expansion and contraction vibration on the opposite sides in two directions, it faces one node in one direction. This includes both cases where both sides contact each other and both sides that oppose another node in another direction, and further cases where each node opposes a plurality of nodes in different directions. The portion of the piezoelectric vibrator to be pressed against is a portion of the piezoelectric vibrator to be pressed against the moving body.

According to this, the piezoelectric vibrator oscillates elliptically by the bending vibration and the expansion and contraction vibration, while the pressing member applies a portion of the piezoelectric vibrator opposite to the portion to be pressed to the pressed portion. Since the piezoelectric vibrator and the moving body are pressed against each other, a frictional force is generated between the two and the moving body is moved. In particular, since the part on the opposite side of the pressure contact part is directly pressurized, all the pressing force is applied to the entire pressure contact part of the piezoelectric vibrator and the moving body, and the balance of vibration does not collapse and the position of the node does not move, so the support part The vibration loss at is very small. Further, since the supporting member does not shift due to the pressing force, a large pressing force can be applied, and a large frictional force is generated. On the other hand, since the node guide member contacts the node of the bending vibration or the expansion / contraction vibration, it does not hinder the bending vibration or the expansion / contraction vibration. Also, in a node of bending vibration, etc., in at least two directions perpendicular to the pressing direction, the piezoelectric vibrator is brought into contact with the opposing sides, and when the bending vibration and the stretching vibration occur, the piezoelectric vibrator is moved in the pressing direction. Since the guide is guided only in the pressing direction without moving in the vertical direction, the bending vibration and the expansion and contraction vibration generated in the piezoelectric vibrator are stabilized, and the pressure contact portion of the piezoelectric vibrator with the moving body is not displaced. Therefore, a large pressing force is applied between the piezoelectric vibrator and the moving body, generating a large torque,
Stabilize torque.

According to a second aspect of the present invention, there is provided an ultrasonic motor in which a piezoelectric vibrator which performs elliptical vibration by bending vibration and expansion / contraction vibration is pressed into contact with the piezoelectric vibrator to take out an output, and the portion of the piezoelectric vibrator to be brought into pressure contact with the piezoelectric vibrator. On the other hand, a pressing member for pressing the opposite side to the pressing side, and a node of the stretching vibration of the piezoelectric vibrator, in at least one direction perpendicular to the pressing direction, abutting on opposite sides. A joint guide member for guiding the piezoelectric vibrator in the pressing direction,
An end of the piezoelectric vibrator opposite to the press-contact side, in at least another direction perpendicular to the pressing direction, abutting on opposite sides, and moving the piezoelectric vibrator in the pressing direction. And an end guide member for guiding.

According to this, while the piezoelectric vibrator oscillates in an elliptical manner by the bending vibration and the expansion and contraction vibration, the pressing member presses the piezoelectric vibrator from the side opposite to the press-contact side to the press-contact side to be driven. To the moving object. A frictional force is generated at a pressure contact portion between the piezoelectric vibrator and the moving body, and the moving body is moved in a predetermined direction by the frictional force. On the other hand, the node guide member does not move the piezoelectric vibrator in one direction perpendicular to the pressing direction, and the end guide member moves the piezoelectric vibrator in another direction perpendicular to the pressing direction. Without doing so, the piezoelectric vibrator does not move in the direction perpendicular to the pressurizing direction and is guided in the pressurizing direction, so that the bending vibration and stretching vibration generated in the piezoelectric vibrator are stable, and the piezoelectric vibrator Is not displaced.

According to a third aspect of the present invention, there is provided an ultrasonic motor in which a piezoelectric vibrator which performs elliptical vibration by bending vibration and expansion / contraction vibration is brought into pressure contact with the piezoelectric vibrator to take out an output, and a portion of the piezoelectric vibrator which is brought into pressure contact with the piezoelectric vibrator. A pressing member that presses a portion on the opposite side to the press contact portion, and at least one node of the bending vibration or the stretching vibration of the piezoelectric vibrator, in one direction perpendicular to the pressing direction. A node guide member that abuts on opposing sides and guides the piezoelectric vibrator in the pressing direction, and pressurizes at least one node of the bending vibration or the stretching vibration of the piezoelectric vibrator. A fixing member fixed in another direction perpendicular to the direction, and the fixing member, in the other direction, abutting on opposite sides, and paired with the fixing member; Characterized by comprising a guide member for guiding said the pressure direction piezoelectric vibrator, a.

According to this, since the pressing member presses the corresponding portion of the piezoelectric vibrator opposite to the portion to be pressed against the pressed portion, all the pressing force is applied to the pressed portion. The node guide member contacts the opposing sides of the piezoelectric vibrator in one direction perpendicular to the pressing direction, and thus guides the piezoelectric vibrator in the pressing direction without moving the piezoelectric vibrator in one direction. The guide member abuts on opposite sides of the fixed member in the other direction perpendicular to the pressing direction, does not move the fixed member in the other direction, guides the fixed member in the pressing direction, and fixes the piezoelectric member to the fixed member. The vibrator is also guided in the pressing direction without moving in the other direction. That is, since the piezoelectric vibrator does not move in the direction perpendicular to the pressing direction but is guided in the pressing direction, the bending vibration and the expansion and contraction vibration generated in the piezoelectric vibrator are stable, and the piezoelectric vibrator can move with the moving body. Is not displaced.

According to a fourth aspect of the present invention, there is provided an ultrasonic motor in which a piezoelectric vibrator which performs elliptical vibration by bending vibration and expansion / contraction vibration is pressed and brought into contact with the piezoelectric vibrator to take out an output. A fixing member fixed in a direction perpendicular to the direction in which the piezoelectric vibrator is pressed against at least one node of the bending vibration or the expansion and contraction vibration, and is fitted with the fixing member to be perpendicular to the pressing direction. While limiting the movement of the piezoelectric vibrator in the direction,
A guide member for guiding the fixing member in the pressing direction.

According to this, the fixing member fits with the guide member and does not move the piezoelectric vibrator in a direction perpendicular to the pressing direction, the guide member guides the fixing member in the pressing direction,
Since the piezoelectric vibrator fixed to the fixed member is similarly guided in the pressing direction, the bending vibration and the expansion / contraction vibration generated in the piezoelectric vibrator are stabilized, and the pressure contact portion of the piezoelectric vibrator with the moving body is not displaced.

According to a fifth aspect of the present invention, there is provided an ultrasonic motor in which a piezoelectric vibrator which performs elliptical vibration by bending vibration and expansion / contraction vibration is pressed and brought into contact with the piezoelectric vibrator to take out an output. A fixing member fixed in a direction perpendicular to a direction in which the piezoelectric vibrator is pressed against at least one node of the bending vibration or the stretching vibration, and a direction in which the fixing member is pressed with the piezoelectric vibrator. A guide member that abuts on opposite sides in at least two perpendicular directions and guides the fixing member in the pressing direction.

According to this, the guide member abuts on both opposing sides in at least two different directions perpendicular to the direction in which the piezoelectric vibrator is pressed out of the fixed member. It is guided in the pressing direction without moving in the vertical direction, and the piezoelectric vibrator fixed to the fixed member is also guided in the pressing direction without moving in the direction perpendicular to the pressing direction, so it occurs in the piezoelectric vibrator The bending vibration and the stretching vibration are stable, and the pressure contact portion of the piezoelectric vibrator with the moving body is not displaced.

According to a sixth aspect of the present invention, in the ultrasonic motor according to the fourth or fifth aspect, a pressure member for pressing the piezoelectric vibrator through the fixed member is provided. And According to this, the pressing member presses the fixed member, and the pressing force is transmitted from the fixed member or the guide member to the piezoelectric vibrator, and presses the piezoelectric vibrator and the moving body against each other.

According to a seventh aspect of the present invention, in the ultrasonic motor according to the fourth or fifth aspect, a part of the piezoelectric vibrator opposite to a part to be pressed against is connected to the piezoelectric vibrator. A pressurizing member for pressurizing the press-contact portion is provided. According to this, since the pressing member presses the portion on the opposite side corresponding to the pressed portion of the piezoelectric vibrator to the pressed portion, all the pressing force is applied to the pressed portion of the piezoelectric vibrator against the moving body.

According to an eighth aspect of the present invention, in the ultrasonic motor according to any one of the first, second, fourth, and fifth aspects, the vibration expansion for expanding the elliptical vibration at the pressure contact portion of the piezoelectric vibrator. A member is provided. According to this, since the vibration expanding member expands the elliptical vibration, a large moving speed is generated.

According to a ninth aspect of the present invention, in the ultrasonic motor according to the eighth aspect, the vibration enlarging member includes:
It is characterized by having a curved surface for uniformizing wear due to friction generated by the pressurization. According to this, even when the vibration enlarging member moves in the direction opposite to the moving direction of the moving body due to the small gap of the guide section such as the support section, the vibration expanding member always moves uniformly with the moving body, so that a constant pressing force is always applied to the moving body. And add propulsion to stabilize torque and speed.

According to a tenth aspect of the present invention, in the ultrasonic motor according to the eighth aspect, the same balance as that of the vibration enlarging member is provided on a portion of the piezoelectric vibrator opposite to the pressure contact portion. According to this feature, the protrusion is provided, and the balance protrusion makes the moment of inertia of the vibration enlarging member side equal to the moment of inertia of the balance protrusion side with respect to the piezoelectric vibrator, and balances the vibration balance of the piezoelectric vibrator. Maintain and stabilize bending vibration and expansion / contraction vibration, and at the same time prevent spurious vibration.

According to an eleventh aspect of the present invention, in the ultrasonic motor according to any one of the first, second, fourth, and fifth aspects, the joint guide member, the end guide member, and the fixing member include: The piezoelectric vibrator is made of a material having a lower elastic modulus than the piezoelectric vibrator. As mentioned above, materials with low elastic modulus
It includes resin and rubber, and the resin includes, for example, plastic. According to this, the node guide member and the like are made of a low elastic modulus material, do not transmit bending vibration or expansion and contraction vibration, and do not attenuate bending vibration and the like, so that a large torque is generated with high efficiency.

According to a twelfth aspect of the present invention, in the ultrasonic motor according to any one of the first, second, fourth, and fifth aspects, the joint guide member or the end guide member and the piezoelectric vibrator are connected to each other. A low elastic modulus member having a low elastic modulus is provided therebetween. According to this, the low elastic modulus member does not transmit the bending vibration or the stretching vibration from the piezoelectric vibrator and does not attenuate the bending vibration or the stretching vibration, so that a large torque is generated with high efficiency.

According to a thirteenth aspect of the present invention, in the ultrasonic motor according to the fourth or fifth aspect, both electrodes are provided between the electrode formed on the piezoelectric vibrator and the fixing member. Characterized in that an insulating space is provided to insulate them. According to this, the electrode and the fixing member are insulated by the insulating space, and the drive signal does not short-circuit.

According to a fourteenth aspect, in the ultrasonic motor according to any one of the first, second, and seventh aspects,
A low elastic modulus member having a lower elastic modulus than the piezoelectric vibrator is provided between the pressing member and the piezoelectric vibrator. According to this, the low elastic modulus member does not transmit the bending vibration or the stretching vibration from the piezoelectric vibrator and does not attenuate the bending vibration or the stretching vibration, so that a large torque is generated with high efficiency.

According to a fifteenth aspect of the present invention, in the ultrasonic motor according to any one of the first to fourth aspects, the piezoelectric vibrator is a first piezoelectric vibrator that generates expansion and contraction vibration. And a second piezoelectric vibrator that generates bending vibration. According to this, the first piezoelectric vibrator performs expansion and contraction vibration, and the second piezoelectric vibrator performs bending vibration, causing elliptical vibration with large vibration displacement and generating large torque.

According to a sixteenth aspect of the present invention, there is provided an electronic apparatus using a stage using the ultrasonic motor according to any one of the first to fifteenth aspects. Here, the electronic device includes a measuring device, a processing device, a magnetic recording device and the like, and the stage is used for a moving stage of the measuring device, a moving stage of a workpiece of the processing device, a movement of a magnetic recording medium, and the like. According to this, an electronic device using the ultrasonic motor of the present invention is realized.

[0028]

Embodiments of the present invention will be described below in detail with reference to FIGS. Embodiment 1 FIG. 1 shows an ultrasonic motor according to Embodiment 1 to which the present invention is applied. FIG. 1A shows a front structure, and FIG. 1B shows a bottom structure. The ultrasonic motor includes a piezoelectric vibrator 11, a vibration magnifying member 12 of the present invention provided on the bottom surface of the piezoelectric vibrator 11 in the drawing, and a low elastic modulus member 13 provided on the top surface of the piezoelectric vibrator 11 in the drawing. Piezoelectric vibrator 11
And a pressing member 15 provided on the upper surface of the guide case 14.
And a guide plate 16 in which the side portions of the guide case 14 are fitted. The distal end of the vibration expanding projection 12 is pressed against the moving body 17.

FIGS. 2 and 3 are views showing the structure and vibration state of the piezoelectric vibrator. The piezoelectric vibrator 11 includes a first piezoelectric vibrator 111 and a second piezoelectric vibrator 111 laminated on the first piezoelectric vibrator 111.
Of the piezoelectric vibrator 112. Each piezoelectric vibrator 111, 1
12 is manufactured using a piezoelectric material such as barium titanate, lead zirconate titanate, lithium niobate and lithium tantalate. The first piezoelectric vibrator 111 includes:
In the drawing, substantially the entire surface is polarized in the thickness direction with the front side being (-) and the back side being (+), thereby forming a polarized portion 111a. Further, electrodes are formed on the entire front surface and the entire rear surface. The second piezoelectric vibrator 112 divides a rectangular body into four parts, and firstly polarizes the divided parts in the thickness direction with (+) on the front side and (−) on the back side in each figure, Second polarization section 112
b, a third polarized portion 112c and a fourth polarized portion 112d. An electrode is formed on the front side of each of the polarized portions 112a... 112d, while an electrode is formed on the entire back side of the second piezoelectric vibrator 112 as a counter electrode. In addition, the electrode of the first polarization section 112a and the electrode of the second polarization section 112b are electrically connected by a conductor, and the electrode of the third polarization section 112c and the electrode of the fourth polarization section 112d are electrically connected by a conductor.

The polarization section 111a of the first piezoelectric vibrator 111 and the first polarization section 11a of the second piezoelectric vibrator 112
When a drive signal is input to 2a and the second polarization unit 112b,
As shown in FIG. 2, the stretching vibration V1 is the first piezoelectric vibrator 1
11, a bending vibration V2 and a stretching vibration (not shown) occur in the second piezoelectric vibrator 112, and an elliptical vibration V3 rotating in one direction is caused by the bending vibration V2 and the like and the stretching vibration V1 on each peripheral surface of the piezoelectric vibrator 11. Occurs. As described above, since the first piezoelectric vibrator 111 and the second piezoelectric vibrator 112 generate the stretching vibration V1 and the bending vibration V2, respectively, the elliptical vibration V3 of the piezoelectric vibrator 11 is greatly displaced, and a large torque is generated. Cause. On the other hand, when a drive signal is input to the third polarization part 112c and the fourth polarization part 112d of the second piezoelectric vibrator 112 and the polarization part 111a of the first piezoelectric vibrator 111, as shown in FIG. A bending vibration V4 having a phase difference of 180 ° from the vibration V1 and a stretching vibration (not shown) are generated in the second piezoelectric vibrator 112, and an elliptical vibration V5 rotating in a direction opposite to the elliptical vibration V3 is generated in the piezoelectric vibrator 11. In addition, using only the second piezoelectric vibrator 112, the bending vibration V2 generated in the second piezoelectric vibrator 112,
Elliptical vibration may be generated in the piezoelectric vibrator 11 by V4 and the stretching vibration.

FIG. 4 shows the positions of nodes of stretching vibration and bending vibration generated in the piezoelectric vibrator. When the stretching vibration V1 occurs with respect to the rectangular piezoelectric vibrator 11 shown in FIG. 4A, the center of the long side of the rectangular body becomes the node N1 as shown in FIG. 4B. On the other hand, when the bending vibrations V2 and V4 occur, three portions become nodes N2, N3 and N4 at equal intervals along the long side of the rectangular body.
In the present embodiment, the position of the node N1 of the stretching vibration V1 and the position of the node N3 of the bending vibrations V2 and V4 match.

Also, as shown in FIG.
2 is a pressure contact portion 11 of the piezoelectric vibrator 11 with the moving body 17.
a, that is, it is fixed to the approximate center of the short side. And
The elliptical vibrations V3 and V5 of the piezoelectric vibrator 11 are enlarged, and the piezoelectric vibrator 11 is pressed against the moving body 17 with a large vibration displacement to generate a large frictional force with the moving body 17.

The low elastic modulus member 13 is made of a material having a lower elastic modulus than the piezoelectric vibrator 11, for example, resin, rubber, or plastic.
2, V4 is not transmitted to the guide case 14, and the stretching vibration V1
Etc. are not attenuated.

The guide case 14 has a front U-shaped main body, and first joint guide portions 14a, 14a projecting toward the piezoelectric vibrator 11 from both arms of the U-shaped main body in the figure. Of the piezoelectric vibrator 1 from the upper part of the main body.
1 comprises a protruding portion 14c protruding toward the first portion. here,
The guide case 14 does not transmit bending vibration and expansion / contraction vibration and does not attenuate bending vibration and the like.
It is made of a material having a lower elastic modulus than 1, for example, resin such as plastic or rubber. The first joint guides 14a, 14a,
As shown in FIG. 1B, the piezoelectric vibrator 11 is located at a node N2 of the bending vibration, and is a node N2 of the piezoelectric vibrator 11 in a width direction perpendicular to the direction in which the pressing member 15 is pressed. Abut on both opposing parts in the thickness direction. Since the piezoelectric vibrator 11 does not move in the direction perpendicular to the pressing direction but is guided in the pressing direction, the bending vibration and the stretching vibration are stable, and the pressure contact between the piezoelectric vibrator 11 and the moving body 17 is performed. The part does not displace. Second joint guides 14b, 14
b is located at the node N4 of the bending vibration of the piezoelectric vibrator 11, is the node N4 of the piezoelectric vibrator 11, and oppose each other in the width direction perpendicular to the pressing direction of the pressing member 15, and In the thickness direction perpendicular to the pressurizing direction, it contacts both opposing parts. A low-elastic sheet made of a resin such as rubber or plastic having a lower elastic modulus than the piezoelectric vibrator 11 is provided between the first and second joint guides 14 a and 14 b and the piezoelectric vibrator 11. It may be interposed. The protrusion 14 c is a pressure contact portion 11 a of the piezoelectric vibrator 11 with the moving body 17, that is, a portion where the vibration magnifying member 12 is provided,
And a pressure member 1
5 is transmitted to the piezoelectric vibrator 11.

The pressing member 15 uses, for example, a coil spring, and has a protrusion 14 c of the guide case 14 and a low elastic modulus member 13.
Of the piezoelectric vibrator 11 with the moving body 17
The corresponding part on the opposite side to 1a is pressed to the pressure contact part. Since all the pressing force is applied to the moving body 17 via the vibration expanding member 12, the vibration expanding member 12 and the moving body 17
And the frictional force generated between them increases. The pressing member 1
An elastic member such as rubber or a leaf spring may be used for 5. The guide plate 16 is formed with a guide groove 16a in which the side portion of the guide case 14 is inserted, along the pressing direction of the pressing member 15, and guides the guide case 14 in the pressing direction.

Next, a method of using the ultrasonic motor will be described with reference to FIGS. When moving the moving body 17 in one direction, the polarization unit 1 of the first piezoelectric vibrator 111
11a, first polarization section 112 of second piezoelectric vibrator 112
a, A driving signal may be input to the second polarization unit 112b. The stretching vibration V1 occurs in the first piezoelectric vibrator 111, the bending vibration V2 occurs in the second piezoelectric vibrator 112, and the elliptical vibration V3 occurs on the peripheral surface of the piezoelectric vibrator 11. Elliptical vibration V3
Is enlarged by the vibration enlarging member 12. on the other hand,
The pressing member 15 is connected to the moving body 1 of the piezoelectric vibrator 11 through the protrusion 14 c of the guide case 14 and the low elasticity member 13.
A corresponding portion on the opposite side of the pressure contact portion 11a with the member 7 is pressed toward the pressure contact portion 11a, and the vibration expanding member 12 is pressed against the moving body 17. At this time, all the pressing force is applied to the pressure contact portion 11a between the piezoelectric vibrator 11 and the moving body 17, and the guide case 14 also moves the piezoelectric vibrator 11 in the pressing direction against the bending vibration and the stretching vibration. Since the piezoelectric vibrator 11 is guided only in the pressing direction without moving in the vertical direction, the bending vibration and the stretching vibration generated in the piezoelectric vibrator 11 are stable, and the pressure contact portion 11a of the piezoelectric vibrator 11 with the moving body 17 does not slip. A large pressing force is applied between the piezoelectric vibrator 11 and the moving body 17.
Then, a large frictional force is generated between the vibration expanding member 12 and the moving body 17, and the moving body 17 moves in one direction at a high speed.

On the other hand, when moving the moving body 17 in the opposite direction, the polarization portion 111a of the first piezoelectric vibrator 111 and the second
A drive signal may be input to the third polarization section 112c and the fourth polarization section 112d of the piezoelectric vibrator 112. Telescopic vibration V
1 is generated in the first piezoelectric vibrator 111, bending vibration V4 is generated in the second piezoelectric vibrator 112, reverse rotation elliptical vibration V5 is generated on the peripheral surface of the piezoelectric vibrator 11, and the elliptical vibration V5 is vibration expansion. It is enlarged by the member 12. On the other hand, the pressing member 1
5 is a projection 14c of the guide case 14, the low elasticity member 1
The portion of the piezoelectric vibrator 11 on the side opposite to the pressure contact portion 11a with the moving body 17 is pressurized toward the pressure contact portion 11a via the piezoelectric vibrator 11, and the vibration magnifying member 12 is pressed on the moving body 17. Then, the moving body 17 receives the frictional force in the opposite direction and moves in the direction opposite to the one direction.

As described above, according to the present embodiment, all the pressing force is applied to the pressure contact portion 11a between the vibration expanding projection 12 provided on the piezoelectric vibrator 11 and the moving body 17 by the pressing portion member 15, Generates large torque. In addition, the guide case 14 guides the piezoelectric vibrator 11 only in the pressing direction without moving the piezoelectric vibrator 11 in the direction perpendicular to the pressing direction even with respect to the bending vibration and the expansion / contraction vibration. The bending vibration and the stretching vibration are stable. Therefore, the piezoelectric vibrator 1
Since the pressure contact portion 11 a of the piezoelectric vibrator 11 does not slip, the vibration magnifying member 1
A large pressing force is applied between the moving body 2 and the moving body 17 to generate a large torque and stabilize the torque. Further, the first piezoelectric vibrator 111 and the second piezoelectric vibrator 112
Are laminated, and the stretching vibration V1 and the bending vibration V
2, the elliptical vibration V3 of the piezoelectric vibrator 11 is greatly displaced and generates a larger torque. Also,
The vibration magnifying member 12 includes an elliptical vibration V3 of the piezoelectric vibrator 11,
Since V5 is enlarged to generate a large frictional force with the moving body 17, a large torque is generated to move the moving body 17 at high speed. Further, the pressing member 15 and the piezoelectric vibrator 1
Since the low elastic modulus member 13 is interposed between the first member 1 and the second member 1, transmission of bending vibration and stretching vibration is prevented, and bending vibration and the like are not attenuated. Further, since the guide case 14 is made of a material having a lower elastic modulus than the piezoelectric vibrator 11, transmission of bending vibration and expansion / contraction vibration is prevented, and bending vibration and the like are not attenuated. The first
If a low elastic modulus sheet having a lower elastic modulus than the piezoelectric vibrator 11 is interposed between the joint guide portion 14a, the second joint guide portion 14b, and the piezoelectric vibrator 11, transmission of bending vibration and stretching vibration can be achieved. To prevent bending vibration and the like.

Embodiment 2 FIGS. 5A and 5B show an ultrasonic motor according to Embodiment 2 to which the present invention is applied. FIG. 5A shows a front structure, and FIG. 5B shows a bottom structure. Show.
The ultrasonic motor includes a piezoelectric vibrator 11 and a piezoelectric vibrator 1.
1 and a piezoelectric vibrator 11
The balance projection 21 provided on the opposite side of the vibration expanding member 12, the pressing member 15 pressed against the upper surface of the balance projection 21, and the node guide of the present invention contacting the nodes of the expansion and contraction vibration of the piezoelectric vibrator 11. It comprises a guide case 22 as a member. Note that the same members as those in the first embodiment are given the same reference numerals and description thereof is omitted.

Here, the balance projection 21 is the same as the vibration magnifying member 12 and is provided at a corresponding portion of the piezoelectric vibrator 11 on the side opposite to the vibration magnifying member 12.
Then, the vibration balance of the piezoelectric vibrator 11 is maintained, and the bending vibration and the stretching vibration are stabilized. The guide case 22 is shown in FIG.
As shown in (b), a substantially cross-shaped space 2 is formed inside the rectangular body.
2a, and the piezoelectric vibrator 1 is inserted into the cross-shaped space 22a.
1 and the inner surface of the guide case 22 is brought into contact with both portions of the piezoelectric vibrator 11 facing each other in the width direction and both portions facing each other in the thickness direction. And the piezoelectric vibrator 1
1 is guided in the pressing direction without moving in the direction perpendicular to the pressing direction.

Next, the operation of the ultrasonic motor will be described. A bending vibration and a stretching vibration are generated in the piezoelectric vibrator 11, and an elliptical vibration is generated on the peripheral surface.
The vibration is expanded by the vibration expanding member 12. On the other hand, the pressing member 1
5 presses the piezoelectric vibrator 11 via the balance projection 21 to bring the vibration expanding member 12 and the moving body 17 into pressure contact with each other. At this time, the guide case 22 does not move the piezoelectric vibrator 11 in a direction perpendicular to the pressing direction, stabilizes the bending vibration and the expansion / contraction vibration, and moves the moving body 1 of the vibration magnifying member 12.
7 is not displaced. Also, balance projection 2
1 is the moment of inertia of the upper and lower parts of the piezoelectric vibrator 11,
Since the rigidity is made equal and the balance of the piezoelectric vibrator 11 is maintained, the bending vibration and the like are stabilized, and are formed around the nodes. Then, a frictional force is generated between the moving body 17 and the vibration expanding member 12, and the moving body 17 moves in one direction.

As described above, according to the present embodiment, the guide case 22 guides the piezoelectric vibrator 11 only in the pressing direction without moving the piezoelectric vibrator 11 in the direction perpendicular to the pressing direction. Vibration stabilizing member 1
A large pressing force is applied between the piezoelectric vibrator 11 and the moving body 17 so as not to slide the press contact portion between the moving body 17 and the moving body 17. As a result, a large torque is generated as in the first embodiment, and the torque is stabilized. Also,
Since the balance of the piezoelectric vibrator 11 is maintained by the balance projection 21, the bending vibration and the expansion and contraction vibration are stabilized.

Third Embodiment FIGS. 6A and 6B show an ultrasonic motor according to a third embodiment to which the present invention is applied, wherein FIG. 6A shows a front structure, and FIG. 6B shows a bottom structure. The ultrasonic motor includes a piezoelectric vibrator 11, a vibration magnifying member 23 provided on the lower surface of the piezoelectric vibrator 11, and a guide case 24 provided as a node guide member of the present invention provided around a vibrating node of the piezoelectric vibrator 11.
And a low elastic modulus member 13 provided on the upper surface of the piezoelectric vibrator 11.
And a pressurizing member 15 pressed against the upper surface of the low elastic modulus member 13.

Here, the low elastic modulus member 13 does not transmit bending vibration and expansion / contraction vibration from the piezoelectric vibrator 11 to the pressing member 15 and does not attenuate bending vibration and the like. Vibration expanding member 23
Has a curved surface 23a at a pressure contact portion with the moving body 17. This curved surface 23a makes the friction generated between the vibration expanding member 23 and the moving body 17 uniform when the vibration expanding member 23 is inclined and pressed against the pressing direction, and does not abruptly wear a specific portion. Then, a constant pressure is applied to the moving body 17 to move the moving body 17 at a constant speed. The guide case 24 includes a first node guide portion 24a, 24a, a second node guide portion 24b, 24b protruding toward a node of bending vibration of the piezoelectric vibrator 11 in a rectangular parallelepiped having a hollow inside, Third node guides 24c, 24 protruding toward nodes of expansion and contraction vibration of piezoelectric vibrator 11
c and 24c. The first joint guides 24a, 24a,
The second node guides 24b, 24b are nodes of bending vibration of the piezoelectric vibrator 11, and abut on both opposing portions in the width direction perpendicular to the pressing direction. In addition, the third joint guide portion 24c,
Reference numerals 24c, 24c denote expansion / contraction vibration nodes of the piezoelectric vibrator 11, and abut on opposite sides in the thickness direction perpendicular to the pressing direction. Then, the first joint guide portions 24a, 24a of the guide case 24, the second joint guide portions 24b, 24b
Does not move the piezoelectric vibrator 11 in the width direction perpendicular to the pressurizing direction, and does not move the third node guides 24c, 24c,
4c does not move the piezoelectric vibrator 11 in the thickness direction perpendicular to the pressing direction. That is, the piezoelectric vibrator 11 is guided in the pressing direction without moving in the direction perpendicular to the pressing direction.

As described above, according to the present embodiment, the guide case 24 guides the piezoelectric vibrator 11 in the pressing direction without moving the piezoelectric vibrator 11 in the direction perpendicular to the pressing direction. The same effect as that of No. 1 can be obtained. Also, the portion of the vibration magnifying member 23 that is pressed against the moving body 17 is defined by a curved surface 23.
Since a is set to “a” and uneven wear due to friction generated between the moving body 17 and the moving body 17 is prevented, a constant pressing force is applied to the moving body 17 and the torque becomes constant.

Embodiment 4 FIGS. 7A and 7B show an ultrasonic motor according to Embodiment 4 to which the present invention is applied, wherein FIG. 7A shows a front structure, and FIG. 7B shows a bottom structure. The ultrasonic motor includes a piezoelectric vibrator 11, a vibration magnifying member 12 provided on a lower surface of the piezoelectric vibrator 11, a node guide member of the present invention disposed around the piezoelectric vibrator 11, and a guide case 25 as a guide member.
A fixing member 26 fixed to a node of the stretching vibration of the piezoelectric vibrator 11;
And a pressurizing member 15 which presses against a portion on the opposite side to the pressurized member.

Here, the guide case 25 is a rectangular parallelepiped with a hollow inside, and the first node guide portions 25a, 25a and the second node projecting inward at the position of the node of the bending vibration of the piezoelectric vibrator 11. It has guide portions 25b, 25b, and guide grooves 25c, 25c are formed on both opposing inner surfaces of the rectangular parallelepiped along the pressing direction. The first node guides 25a, 25a and the second node guides 25b, 25b are nodes of bending vibration of the piezoelectric vibrator 11, and are opposed to each other in the width direction perpendicular to the pressing direction. Contact the site. As shown in FIG. 2B, the end faces of the fixing members 26, 26 are formed in the guide grooves 25 in the thickness direction perpendicular to the pressing direction of the piezoelectric vibrator 11.
c, 25c. And the guide case 25
First joint guides 25a, 25a, second joint guides 25
b and 25b guide the piezoelectric vibrator 11 in the pressing direction without moving the piezoelectric vibrator 11 in the width direction perpendicular to the pressing direction. The fixing members 26, 26 and the guide grooves 25c, 25c guide the piezoelectric vibrator 11 in the pressing direction without moving the piezoelectric vibrator 11 in the thickness direction perpendicular to the pressing direction. That is, since the piezoelectric vibrator 11 is guided in the pressing direction without moving in the direction perpendicular to the pressing direction, the expansion and contraction vibration and the bending vibration are stable, and the vibration expanding member provided in the piezoelectric vibrator 11 is provided. The pressure contact portion between the moving body 12 and the moving body 17 does not displace.

As described above, according to the present embodiment, the guide case 25 guides the piezoelectric vibrator 11 in the pressing direction without moving the piezoelectric vibrator 11 in the direction perpendicular to the pressing direction. As with 1, large torque can be obtained,
The torque stabilizes.

Fifth Embodiment FIG. 8 shows a front structure of an ultrasonic motor according to a fifth embodiment of the present invention. The ultrasonic motor includes a piezoelectric vibrator 11, a vibration magnifying member 12 provided on a lower surface of the piezoelectric vibrator 11, and a guide member and an end guide member of the present invention provided around the piezoelectric vibrator 11. A case 27, a pressure member 15 that presses against the upper surface of the guide case 27, and a guide plate 16 in which a side portion of the guide case 26 is fitted. The tip of the vibration magnifying member 12 presses against a disk-shaped moving body 28. doing.

Here, the guide case 27 includes node guide portions 27a, 27a projecting from both arms of the U-shaped guide case body toward nodes of the expansion and contraction vibration of the piezoelectric vibrator 11, and a corner of the guide case body. An end guide portion 27b protruding from the portion to the piezoelectric vibrator 11 is provided. The joint guide portions 27a, 27a are the nodes of the stretching vibration of the piezoelectric vibrator 11, and are opposed to each other in the width direction perpendicular to the pressing direction of the pressing member 15 and the thickness perpendicular to the pressing direction. It comes into contact with both parts facing each other in the direction (see FIG. 1B). The end guides 27b, 27b are opposite ends of the piezoelectric vibrator 11 to the vibration magnifying member 12, and are opposed to each other in the width direction perpendicular to the direction in which the pressing member 15 is pressed. In the thickness direction perpendicular to the pressure direction, the portions abut on both opposing portions and the end face on the side opposite to the pressure contact portion with the moving body 27. The joint guides 27a, 27a and the end guides 27b, 27b guide the piezoelectric vibrator 11 in the pressing direction without moving the piezoelectric vibrator 11 in the direction perpendicular to the pressing direction. Also,
The pressurizing member 15 is a member for expanding the vibration
The guide case 27 is pressurized in a direction connecting the corresponding portion on the opposite side to 2 and the vibration expanding member 12, and all the pressing force is applied between the vibration expanding member 12 and the moving body 28.

Next, the operation of the ultrasonic motor will be described. The expansion / contraction vibration and the bending vibration are generated in the piezoelectric vibrator 11, and the piezoelectric vibrator 11 is pressed by the pressing member 15 through the guide case 27, and the vibration expanding member 12 is pressed against the moving body 27. At this time, the node guides 27a, 27
a, the end guides 27b, 27b guide the piezoelectric vibrator 11 in the pressing direction without moving the piezoelectric vibrator 11 in the direction perpendicular to the pressing direction, so that the bending vibration and the stretching vibration are stable, The pressure contact portion of the eleventh moving body 28 does not displace. Then, the moving body 28 rotates in one direction.

As described above, according to the present embodiment, the joint guide portions 27a, 27a of the guide case 27, the end guide portion 27
b and 27b guide the piezoelectric vibrator 11 in the pressing direction without moving the piezoelectric vibrator 11 in the direction perpendicular to the pressing direction, stabilize the bending vibration and the stretching vibration, and allow the piezoelectric vibrator 11 to move with the moving body 28. Since the press-contact portion is not displaced, a large pressing force is applied to the press-contact portion of the vibration expanding member 12 and the moving body 28, thereby generating a large torque and stabilizing the torque. further,
Since the pressing member 15 presses the vibration expanding member 12 from a corresponding portion on the opposite side to the vibration expanding member 12, all the pressing force is applied between the vibration expanding member 12 and the moving body 28, Generates large torque.

Embodiment 6 FIGS. 9A and 9B show an ultrasonic motor according to Embodiment 6 to which the present invention is applied, wherein FIG. 9A shows a side structure, FIG. 9B shows a back surface structure, and FIG. Indicates the structure observed from the bottom. The ultrasonic motor includes a laminated piezoelectric vibrator 31, a vibration magnifying member 12 provided on the bottom surface of the piezoelectric vibrator 31, a fixed member 32 fixed to a node of the bending vibration of the piezoelectric vibrator 31, The vibration magnifying member 12 includes a pressure member 15 for pressing the upper surface of the child 31 and a guide plate 33 as a guide member of the present invention fitted to the fixed member 32.
Is in pressure contact with the moving body 17.

FIG. 10 is a diagram showing a laminated structure of the piezoelectric vibrator. The piezoelectric vibrator 31 includes a first piezoelectric vibrator 311 and a second piezoelectric vibrator 312 shown in FIGS.
, The third piezoelectric vibrator 313 and the fourth piezoelectric vibrator 31
4 is laminated and baked. The first piezoelectric vibrator 311 and the second piezoelectric vibrator 312 are shown in FIG.
As shown in (b), a polarization process is performed on substantially the entire surface with the front side (+) in the figure and the back side (-), and the polarization parts 311a and 311
2a. Further, electrodes are formed on the front side corresponding to the polarization parts 311a and 312a. Further, two through holes 311b and 31 through which the fixing member 32 penetrates the nodes of the bending vibration.
1b, 312b and 312b are formed. As shown in FIGS. 3C and 3D, the third piezoelectric vibrator 313 and the fourth piezoelectric vibrator 314 have a front side of (+) and a rear side of each of the four divided rectangular bodies. (−) To perform a polarization process, the first polarization parts 313a and 314a, the second polarization parts 313b and 314b, and the third polarization parts 313c and 31
4c, and fourth polarization portions 313d and 314d. Further, through holes 313e, 313e, 314e, and 314e for penetrating the fixing member 32 are formed in the nodes of the bending vibration.

As shown in FIG. 9E, the first piezoelectric vibrator 311, the second piezoelectric vibrator 312, the third piezoelectric vibrator 313, and the fourth piezoelectric vibrator 314 are provided on the back side. , An electrode is formed on substantially the entire surface, and serves as a counter electrode of the electrode on the front side. On one side surface of the piezoelectric vibrator 31, a first side surface electrode 31a and a second side surface electrode 31 are provided as shown in FIG.
b, A third side electrode 31c is formed in the thickness direction, and a fourth side electrode and a fifth side electrode are formed on the opposite side. The first side surface electrode 31a conducts between the electrode formed on the polarized portion 311a of the first piezoelectric vibrator 311 and the electrode formed on the polarized portion 312a of the second piezoelectric vibrator 312. The second side surface electrode 31b is connected to the electrode formed on the first polarization section 313a of the third piezoelectric vibrator 313 and the fourth piezoelectric vibrator 314.
Is electrically connected to the electrode formed on the first polarized portion 314a. The third side electrode 31c is connected to the third piezoelectric vibrator 313.
The electrode formed on the fourth polarized portion 313d of the fourth piezoelectric vibrator 314 is electrically connected to the electrode formed on the fourth polarized portion 314d of the fourth piezoelectric vibrator 314. The fourth side electrode is a third piezoelectric vibrator 31.
The electrode formed on the third polarized portion 313b of the third piezoelectric vibrator 314 is electrically connected to the electrode formed on the second polarized portion 314b of the fourth piezoelectric vibrator 314. The fifth side electrode is a third piezoelectric vibrator 3
The electrode formed on the third polarization portion 313c of the thirteenth and the electrode formed on the third polarization portion 314c of the fourth piezoelectric vibrator 314 are conducted.

As shown in FIG. 5F, for example, using a first piezoelectric vibrator 311,
1, 321 through each of the piezoelectric vibrators 311, 312,
313 and 314 have through holes 311b, 312b and 313
e, an electrode 311c having a diameter larger than that of 314e may be formed, and annular insulating spaces 311d and 311d may be provided between the electrode 311c and the fixed shafts 321 and 321. In this way, the fixed shafts 321 and 321 are insulated from the electrode 311c, and a short circuit between them is prevented.

Further, as shown in FIG.
Are a fixed shaft 321 penetrating the piezoelectric vibrator 31, rubber sheets 322 and 322 around the fixed shaft 321 and abutting on the piezoelectric vibrator 31, and a plate 323 fixed to the fixed shaft 321 with screws. , Plate 323 and piezoelectric vibrator 3
1 and nuts 324 and 324 disposed between the first and second nuts.
The fixed shafts 321 and 321 are provided with a nut 324 and a plate 3
A screw is formed on the peripheral surface of the portion where the 23 is fixed. Since the rubber sheet 322 has a lower elastic modulus than the piezoelectric vibrator 31, the rubber sheet 322 prevents leakage from the piezoelectric vibrator 31. The plate 323 is formed in a trapezoidal cross section along the pressing direction, as shown in FIG. The assembling method of the fixing member 32 is based on the method of assembling the through hole 3 provided at the node of the bending vibration of the piezoelectric vibrator 31.
11b... 314e through the fixed shaft 321;
With the rubber sheet 322 abutting on both sides of the piezoelectric vibrator 31 along the fixed shaft 321, the nut 3 is attached to the fixed shaft 321.
24 and 324 are passed through the plate 323, and the fixed shaft is rotated 321 to tighten the nuts 324 and 324 to fix the piezoelectric vibrator 31.

The guide plate 33 is provided along the pressing direction of the piezoelectric vibrator 31, and forms a guide groove 33 a having a trapezoidal cross section along the pressing direction.
3 is fitted. The fixing member 32 is guided in the pressing direction in a pair with the plate 323, and the lower side and the oblique side of the guide groove 33a having a trapezoidal cross section are brought into contact with the plate 323. Do not move in the direction perpendicular to the pressure direction. The pressure member 15 presses a portion of the piezoelectric vibrator 31 opposite to the vibration magnifying member 12 to the vibration magnifying member 12. The pressing member 15 may press the fixing shaft 321 of the fixing member 32 in the above-described pressing direction, or may press the end surface of the plate 323.

Next, the operation of the ultrasonic motor will be described. First piezoelectric vibrator 311 and second piezoelectric vibrator 3
12, the third piezoelectric vibrator 313 and the fourth piezoelectric vibrator 314 generate bending vibration, and cause the vibration magnifying member 12 to perform elliptical vibration. On the other hand, the pressing member 15
A corresponding portion on the opposite side of the vibration expanding member 12 is pressed against the vibration expanding member 12. At this time, the guide plate 33 is
Together with 23, the fixing member 32 is guided in the pressing direction, and the fixing member 32 is not moved in the direction perpendicular to the pressing direction. Further, the piezoelectric vibrator 31 fixed to the fixing member 32 is also guided in the pressing direction, and does not move in the direction perpendicular to the pressing direction. Therefore, the bending vibration and the stretching vibration are stable, and the pressure contact portion of the piezoelectric vibrator 31 with the moving body 17 is not displaced. Then, a large frictional force is generated between the vibration expanding member 12 and the moving body 17, and the moving body 17 moves at a high speed.

As described above, according to the present embodiment, the piezoelectric vibrator 31 is guided in the pressing direction by the fixing member 32 and the guide plate 33 so as not to move in the direction perpendicular to the pressing direction. Since the bending vibration and the expansion and contraction vibration are stabilized and the pressure contact portion between the vibration expanding member 12 and the moving body 17 is prevented from slipping, a large pressing force is applied to the piezoelectric vibrator 31 and a large torque is generated. Stabilize torque. Further, since the insulating space 311d is provided between the fixed shaft 321 and the electrode 311c, the fixed shaft 321 and the electrode 311c are insulated, and a short circuit between the electrode 311c and the fixed shaft 321 is prevented. The piezoelectric vibrator 31 causes the first piezoelectric vibrator 311 and the second piezoelectric vibrator 312 to expand and contract, and the third piezoelectric vibrator 313 and the fourth piezoelectric vibrator 314 generate bending vibration. As a result, a larger torque is generated.

Embodiment 7 FIG. 11 shows an ultrasonic motor according to Embodiment 7 to which the present invention is applied.
Shows the structure of the front, and (b) shows the structure of the side. The ultrasonic motor is provided at the piezoelectric vibrator 31, the vibration magnifying members 12, 12 provided on the bottom surface of the piezoelectric vibrator 31, and the corresponding parts of the piezoelectric vibrator 31 opposite to the vibration magnifying members 12, 12. Balance projections 21, 21 and balance projections 21, 2
The piezoelectric vibrator 31 includes a pressing member 15 for pressing the upper surface of the piezoelectric vibrator 1, a fixing member 36 fixed in the thickness direction of the piezoelectric vibrator 31, and a guide member 37 in contact with the fixing member 36.

Here, the fixed member 36 is provided between the fixed shaft 36 a penetrating the node of the stretching vibration of the piezoelectric vibrator 31 in a direction perpendicular to the pressing direction, and the piezoelectric vibrator 31 and the guide member 37. The spacers 36b are provided. The guide member 37 has guide grooves 37 a, 37 a extending in the pressing direction of the piezoelectric vibrator 31 at the respective U-shaped ends. Each side surface of the guide grooves 37a, 37a abuts on both end surfaces facing each other in the thickness direction of the piezoelectric vibrator 31, which is perpendicular to the pressing direction, of the fixed shaft 36a.
In a, the piezoelectric vibrator 31 is in contact with both opposing portions in the longitudinal direction of the piezoelectric vibrator 31 perpendicular to the pressing direction. The guide member 37 guides only the pressing direction without moving the fixed shaft 36a in the direction perpendicular to the pressing direction, and the piezoelectric vibrator 31 with the fixed shaft 36a fixed is also perpendicular to the pressing direction. It is guided in the pressing direction without moving in any direction.

As described above, according to the present embodiment, the guide member 37 and the fixing member 36 guide the piezoelectric vibrator 31 in the pressing direction without moving the piezoelectric vibrator 31 in the direction perpendicular to the pressing direction. Vibration expansion and contraction vibration
Since the pressure contact portions 2 and 12 with the moving body 17 are not displaced, a large pressing force is applied between the moving body 17 and the vibration magnifying members 12 and 12 to generate a large torque and stabilize the torque. . The pressing members 15, 1
5, the vibration expanding members 12, 1 of the piezoelectric vibrators 31
Since the portion opposite to 2 is pressurized toward the vibration expanding members 12, all the pressing force is applied to the pressure contact portion between the vibration expanding members 12, 12 and the moving body 17 to generate a large torque. Let it. Further, since the balance projections 21 are provided on the opposite side of the vibration expanding members 12 of the piezoelectric vibrator 31, the inertia moments of the upper and lower portions of the piezoelectric vibrator 31 are equal, and the piezoelectric vibrator 31 has the same moment of inertia. Vibrator 3
The balance of 1 is maintained, and the bending vibration and the stretching vibration are stabilized.

<< Eighth Embodiment >> FIG. 12 shows an ultrasonic motor according to an eighth embodiment of the present invention.
Shows the structure of the front, and (b) shows the structure of the side. In this ultrasonic motor, the piezoelectric vibrator 31, the vibration expanding members 12 provided on the bottom surface of the piezoelectric vibrator 31, the fixed member 41 fixed to the piezoelectric vibrator 31, and the fixed member 41 were brought into contact with each other. It comprises guide members 42, 42, and pressurizing member 15 pressed against fixed member 41.

Here, the fixing member 41 is a piezoelectric vibrator 31.
Fixed shafts 41a, 41a penetrating the nodes of the bending vibration in the direction perpendicular to the pressing direction, U-shaped members 41c for fixing both ends of the fixed shafts 41a, 41a, U-shaped members 41c, and piezoelectric vibration Spacer 41 provided in space between element 31
b, 41b and columnar members 41d, 41d projecting upward from the upper surface of the U-shaped member 41c in parallel with the pressing direction. The guide members 42 are annular in cross section and extend in the direction in which the piezoelectric vibrator 31 is pressed. Further, the outer peripheral surfaces of the cylindrical members 41d, 41d of the fixing member 41 are brought into contact with the inner peripheral surface, so that the cylindrical members 41d, 41d are slidable.
The guide members 42, 42 are connected to the cylindrical members 41d, 4d.
1d is guided in the pressing direction without moving in the direction perpendicular to the pressing direction. That is, the piezoelectric vibrator 31 fixed to the fixing member 41 does not move in a direction perpendicular to the pressing direction but guides in the pressing direction.

As described above, according to the present embodiment, the piezoelectric vibrator 31 is guided by the fixing member 41 and the guide member 42 in the pressing direction without moving in the direction perpendicular to the pressing direction. Since the bending vibration and the expansion and contraction vibration are stabilized, and the pressure contact portions of the vibration expanding members 12 and 12 with the moving body 17 are not displaced, a large pressing force is applied between the vibration expanding members 12 and 12 and the moving body 17. In addition, it generates a large torque and stabilizes the torque.

<< Embodiment 9 >> FIG. 13 is a block diagram showing an electronic apparatus with an ultrasonic motor according to Embodiment 9 to which the present invention is applied. The ultrasonic motor-equipped electronic device 50 includes the above-described piezoelectric vibrator 51, a moving body 52 movable by the piezoelectric vibrator 51, a pressing mechanism 53 for pressing the moving body 52 and the piezoelectric vibrator 51, This is realized by providing a transmission mechanism 54 that moves in conjunction with 52 and an output mechanism 55 that moves based on the operation of the transmission mechanism 54. Here, as the transmission mechanism 54, for example, a transmission wheel such as a gear wheel or a friction wheel is used. As the output mechanism 55, for example, a shutter drive mechanism and a lens drive mechanism are used in a camera, a pointer drive mechanism and a calendar drive mechanism are used in an electronic timepiece, and a blade feed mechanism and a processing member feed mechanism are used in a machine tool. As the electronic device 50 with an ultrasonic motor, for example, it is applied to an electronic timepiece, a measuring instrument, a camera, a printer, a printing machine, a machine tool, a robot, a moving device, and the like. In addition, if the output shaft is attached to the moving body 52 and a power transmission mechanism for transmitting torque from the output shaft is provided, a driving mechanism is realized by the ultrasonic motor alone.

[0068]

As described above, according to the present invention, since the piezoelectric vibrator is guided only in the pressing direction without moving in the direction perpendicular to the pressing direction, the bending vibration and the stretching vibration generated in the piezoelectric vibrator are reduced. The piezoelectric vibrator is stable, the pressure contact portion of the piezoelectric vibrator with the moving body is not displaced, and a large pressing force is applied between the piezoelectric vibrator and the moving body to generate a large torque and stabilize the torque. Furthermore, the portion of the piezoelectric vibrator opposite to the press-contact portion is pressurized to the press-contact portion, and all the pressing force is applied to the press-contact portion of the piezoelectric vibrator, so that a large pressing force is applied to the piezoelectric vibrator and the moving body. To generate large torque.

[Brief description of the drawings]

FIGS. 1A and 1B show an ultrasonic motor according to a first embodiment to which the present invention is applied, wherein FIG. 1A is an explanatory diagram showing a front structure, and FIG. 1B is an explanatory diagram showing a bottom structure.

FIG. 2 is an explanatory diagram showing a structure and a vibration state of the piezoelectric vibrator according to FIG. 1;

FIG. 3 is an explanatory diagram showing a structure and a vibration state of the piezoelectric vibrator according to FIG. 1;

FIG. 4 is an explanatory diagram showing positions of nodes of stretching vibration and bending vibration generated in the piezoelectric vibrator according to FIG. 1;

5A and 5B show an ultrasonic motor according to a second embodiment to which the present invention is applied, wherein FIG. 5A is an explanatory view showing a front structure, and FIG. 5B is an explanatory view showing a bottom structure.

FIGS. 6A and 6B are explanatory diagrams showing an ultrasonic motor according to a third embodiment to which the present invention is applied, wherein FIG. 6A is a front view structure and FIG. 6B is a bottom view structure.

FIGS. 7A and 7B show an ultrasonic motor according to a fourth embodiment to which the present invention is applied, wherein FIG. 7A is an explanatory view showing a front structure, and FIG.

FIG. 8 shows a front structure of an ultrasonic motor according to a fifth embodiment to which the present invention is applied.

9A and 9B show an ultrasonic motor according to Embodiment 6 to which the present invention is applied, wherein FIG. 9A is a side view structure, FIG. 9B is a rear view structure, and FIG. FIG.

FIG. 10 is an explanatory view showing a laminated structure of the piezoelectric vibrator according to FIG. 9;

11A and 11B show an ultrasonic motor according to a seventh embodiment to which the present invention is applied, wherein FIG. 11A is an explanatory diagram showing a front structure, and FIG. 11B is an explanatory diagram showing a side structure.

FIG. 12 shows an ultrasonic motor according to an eighth embodiment to which the present invention is applied, wherein (a) is a front structure,
(B) is an explanatory view showing a side structure.

FIG. 13 is an explanatory diagram showing a block diagram of an electronic device with an ultrasonic motor according to a ninth embodiment to which the present invention is applied.

FIG. 14 shows a structure of an ultrasonic motor according to the related art.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Ultrasonic motor 11 Piezoelectric vibrator 12 Vibration magnifying member 13 Low elastic modulus member 14 Guide case 15 Pressure member 21 Balance projection 22 Guide case 23 Vibration magnifying projection 24 Guide case 25 Guide case 26 Fixed member 27 Guide case 31 Piezoelectric vibration Child 311c Insulating space 32 Fixed member 33 Guide plate 36 Fixed member 37 Guide member 41 Fixed member 42 Guide member

Claims (16)

[Claims] 1. An ultrasonic motor which presses a piezoelectric vibrator made of at least a piezoelectric element and generates an output by generating a combined vibration of a bending vibration and a stretching vibration, and takes out an output. A pressurizing member that presses the opposite side to the press-contacting part, and at least one node of the bending vibration or the stretching vibration of the piezoelectric vibrator, in at least two directions perpendicular to the pressing direction, An ultrasonic motor comprising: a node guide member that abuts on opposite sides and guides the piezoelectric vibrator in the pressing direction. 2. An ultrasonic motor for extracting an output by pressing a piezoelectric vibrator made of at least a piezoelectric element, which generates a combined vibration of bending vibration and expansion / contraction vibration, wherein the portion of the piezoelectric vibrator to be pressed against A pressurizing member for pressing the opposite side to the press-contact side, and a node of stretching vibration of the piezoelectric vibrator, in at least one direction perpendicular to the pressurizing direction, abutting on opposing sides; A node guide member for guiding the piezoelectric vibrator in a pressing direction, and an end of the piezoelectric vibrator on the opposite side to the press-contact side, facing at least another direction perpendicular to the pressing direction. An end guide member that abuts on both sides and guides the piezoelectric vibrator in the pressing direction. 3. An ultrasonic motor for extracting an output by pressing a piezoelectric vibrator made of at least a piezoelectric element that generates a combined vibration of a bending vibration and a stretching vibration, wherein the ultrasonic vibrating motor includes a portion of the piezoelectric vibrator that is to be pressed against the piezoelectric vibrator. A pressurizing member that presses an opposing portion to the press-contact portion; and at least one node of the bending vibration or the stretching vibration of the piezoelectric vibrator, which opposes in one direction perpendicular to the pressing direction. A node guide member that contacts the piezoelectric vibrator in the pressurizing direction while abutting on both sides of the piezoelectric vibrator; A fixing member that is fixed in another direction perpendicular to the fixing member, wherein the fixing member contacts the opposite sides in the other direction, and is paired with the fixing member. And a guide member for guiding the piezoelectric vibrator in a pressing direction. 4. An ultrasonic motor for extracting an output by pressing a piezoelectric vibrator made of at least a piezoelectric element which generates a combined vibration of a bending vibration and a stretching vibration, wherein the piezoelectric vibrator generates a combined vibration of the bending vibration and the stretching vibration. A fixing member fixed to at least one of the nodes in a direction perpendicular to a direction in which the piezoelectric vibrator is pressed; a fixing member fitted to the fixing member; and the piezoelectric member in a direction perpendicular to the pressing direction. A guide member that restricts movement of the vibrator and guides the fixed member in the pressing direction. 5. An ultrasonic motor for extracting an output by pressing a piezoelectric vibrator made of at least a piezoelectric element which generates a combined vibration of a bending vibration and a stretching vibration, wherein the piezoelectric vibrator generates a combined vibration of the bending vibration and the stretching vibration. A fixing member fixed to at least one of the nodes in a direction perpendicular to the direction in which the piezoelectric vibrator is pressed, and at least two directions perpendicular to the direction in which the piezoelectric vibrator is pressed, wherein the fixing member is , A guide member that abuts on both sides facing each other and guides the fixed member in the pressing direction. 6. The ultrasonic motor according to claim 4, further comprising a pressing member that presses the piezoelectric vibrator through the fixing member. 7. A pressure member for pressing a portion of the piezoelectric vibrator opposite to a portion to be pressed against the pressed portion of the piezoelectric vibrator. An ultrasonic motor as described. 8. An ultrasonic wave according to claim 1, wherein a vibration expanding member for expanding said bending vibration and expansion / contraction vibration is provided at a pressure contact portion of said piezoelectric vibrator. motor. 9. The ultrasonic motor according to claim 8, wherein said vibration expanding member has a curved shape. 10. The ultrasonic motor according to claim 8, wherein the same balance projection as that of the vibration enlarging member is provided on a portion of the piezoelectric vibrator opposite to the press-contact portion. 11. The method according to claim 1, wherein the joint guide member, the end guide member, and the fixing member are made of a material having a lower elastic modulus than the piezoelectric vibrator. 2. The ultrasonic motor according to claim 1. 12. A low elastic modulus member having a lower elastic modulus than the piezoelectric vibrator is provided between the node guide member or the end guide member and the piezoelectric vibrator.
The ultrasonic motor according to any one of 2, 4, and 5. 13. The ultrasonic motor according to claim 4, wherein an insulating space is provided between the electrode formed on the piezoelectric vibrator and the fixing member to insulate them. 14. A low elastic modulus member having a lower elastic modulus than the piezoelectric vibrator is provided between the pressing member and the piezoelectric vibrator. An ultrasonic motor as described. 15. The piezoelectric vibrator according to claim 1, wherein a first piezoelectric vibrator that generates stretching vibration and a second piezoelectric vibrator that generates bending vibration are laminated. The ultrasonic motor according to any one of the above items 5. 16. An electronic device with an ultrasonic motor, comprising the ultrasonic motor according to claim 1. Description: