JPH0638558A - Vibration motor - Google Patents

Abstract

PURPOSE:To provide a vibration motor, in which two rotor parts can be rotated and a structure is simple and can be flattened and a rotational output can be generated efficiently. CONSTITUTION:The title vibrating motor has a stator part 40 and two rotor parts 30A, 30B. The stator part 40 contains ring piezoelectric elements 42, 44, ring-shaped electrode plates 46, 48 stacked on the surfaces of the piezoelectric elements 42, 44 and first and second plate block bodies 50 and 52 arranged in the manner of holding both sides of the electrode plates 46, 48 and piezoelectric elements 42, 44. Radial projections 62A, 62B are formed on both end faces 60A, 60B of the stator part 40. In a state where the second electrode plate 48 is earthed, further, a single-phase AC voltage having the resonance frequency of bending vibration is applied to the alternate ones out of split electrode plates 46 arranged on the ring, an elliptical vibration is generated on the projections 62A, 62B, and the rotor parts 30A, 30B are rotated.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a vibration motor.

[0002]

2. Description of the Related Art Conventionally, a bolt tightening Langevin type ultrasonic motor is well known, for example, a piezoelectric motor using a cantilever torsional ultrasonic transducer disclosed in JP-A-61-49670, An ultrasonic motor and the like according to Japanese Patent Laid-Open No. 63-217984 are known.

However, in the conventional motors of this type, there is a problem that the rotor can rotate only in one direction, and the structure is complicated and expensive.

FIG. 26 shows an example of a conventional bolted Langevin type ultrasonic motor. In this ultrasonic motor, metal block bodies 14 and 16 having different lengths are arranged at both ends of two piezoelectric elements 10 and 12, and both block bodies 14 and 16 are provided with a bolt 18 at the center thereof. It is fixed to tighten.

This ultrasonic motor has an AC power supply 2
When a high frequency AC voltage is applied to the piezoelectric elements 10 and 12 from 0, longitudinal vibration occurs due to the vibration of the piezoelectric elements 10 and 12 in the thickness direction, and torsional vibration occurs due to the twisting of the bolt 18, and the end faces of the block bodies 14 and 16 are generated. The elliptic vibration that is a combination of the longitudinal vibration and the torsional vibration is generated in the, and the rotational driving force can be obtained by the elliptic vibration.

A disk 22 is provided on the end surface of the block body 16.
Is urged toward the block body 16 by a spring 24, and a rotating shaft 26 of the disk 22 is supported by a bearing 28. Therefore, the disc 22 is attached to the block body 16
By making contact with the end surface of the rotating shaft, the rotational force obtained by the combined vibration is transmitted to the disc 22, and the rotational output can be taken out from the rotating shaft 26.

[0007]

However, in the conventional ultrasonic motor, the rotational output cannot be effectively generated unless the resonance points of the longitudinal vibration and the torsional vibration are matched. For this reason, it is necessary to form one block body 14 in a short shape and form the other block body 16 in a long shape so that the resonance points coincide with each other. Therefore, the degree of freedom in designing a motor is small. was there. Further, in order to match the resonance points, the block body 1
Since the entire length of the ultrasonic motor including 4, 16 is formed in a rod shape, there is a problem that the entire length becomes long and it is difficult to flatten and downsize. In addition, in the ultrasonic motor that generates elliptical vibration by combining longitudinal vibration and torsional vibration in this way, the block body 1
Only one direction elliptical vibration can be generated on the end face of 6
There was a problem that 6 could not be driven in both forward and reverse directions. Further, in this ultrasonic motor, elliptical vibration cannot be directly generated from the vibrations of the vibrators 10 and 12, and the longitudinal vibration and the torsional vibration must be combined, so that the elliptic vibration generation efficiency is not sufficient. There is a problem that the rotation output cannot be generated efficiently.

The present invention has been made in view of such conventional problems, and its purpose is to have a large degree of freedom in design, a simple structure and a small size, and to efficiently generate a rotational output. An object of the present invention is to provide a vibration motor that can rotate in both directions as needed and can obtain two rotation outputs.

[0009]

In order to solve the above-mentioned problems, the present invention provides a stator portion having first and second rotor contact surfaces, and a rotary drive in contact with the first and second rotor contact surfaces. A first rotor portion and a second rotor portion,
In the vibration motor, the stator part forms a plurality of voltage application regions on the surface of the piezoelectric device and a surface of the piezoelectric device at predetermined intervals along the rotation direction of the rotor part. An electrode and a flat first block body and a second block body which are fixedly attached to both sides of the piezoelectric element so as to sandwich the piezoelectric element, and whose outer end faces serve as the first and second rotor contact surfaces; A plurality of protrusions provided on the first and second rotor contact surfaces, and by applying an AC voltage to the voltage application region of the piezoelectric element, the first and second rotors of each block body. By generating a standing wave on the contact surface and providing the protrusion between the antinode and the node of the standing wave, elliptical vibration is generated in the protrusion, and the first and second contacting members are in contact with the protrusion. Drive the rotor part of And butterflies.

Further, according to the present invention, there is provided a stator portion having first and second rotor contact surfaces, and a first rotor portion and a second rotor portion which are brought into contact with the first and second rotor contact surfaces to be rotationally driven.
A rotor part, wherein the stator part forms a plurality of voltage application regions along the rotation direction of the rotor part on the surface of the piezoelectric device and the piezoelectric device for generating vibration. An electrode and a flat first block body and a second block body which are fixedly attached to both sides of the piezoelectric element so as to sandwich the piezoelectric element, and whose outer end faces serve as the first and second rotor contact surfaces; A plurality of protrusions provided on the first and second rotor contact surfaces, and by controlling the switching of the alternating voltage applied to the piezoelectric element via the electrodes, the first and second blocks of each block body are controlled. The plurality of protrusions are formed so as to selectively generate a first standing wave and a second standing wave having different phases on the rotor contact surface.
It is formed between the antinode of the first standing wave and the node on one side, and is formed between the antinode of the second standing wave and the node on the other side. It is characterized in that the rotation direction of each rotor portion in contact with the protrusion is switched by switching control and selecting the generated standing wave.

[0011]

According to the invention of claim 1, on the surface of the piezoelectric element,
A plurality of voltage application regions are formed at predetermined intervals along the rotation direction of the rotor portion. Moreover, in the present invention, the block body is formed in a flat shape so that the bending vibration caused by the bending of the beam is generated by the vibration of the piezoelectric element. Therefore, by applying an AC voltage to the plurality of voltage application regions, a standing wave due to the bending of the beam can be generated on the rotor contact surface of the stator part. Moreover, in the present invention, since each of the protrusions is provided between the antinode of the standing wave and the node, elliptical vibration is directly generated on the end surface of the protrusion, and the rotor portion can be rotationally driven.

As described above, in the vibration motor of the present invention, unlike the conventional Langevin type ultrasonic motor, the elliptical vibration is obtained directly from the standing wave obtained by vibrating the piezoelectric element without using the torsional vibration by the bolt. Therefore, the rotation output can be efficiently obtained. Moreover, since there is no design constraint to match the resonance points of the longitudinal vibration and the torsional vibration as in the conventional case, the configuration of the entire motor becomes simple and inexpensive. Further, since the flat block body is used, the vibration motor as a whole can be flattened and downsized.

In particular, according to the present invention, both end surfaces of the stator portion are used as the first and second rotor contact surfaces, and the protrusions provided on the first and second rotor contact surfaces and the first and second rotors. Is in contact with the department. The first and second rotor portions are caused by elliptical vibration generated on the end faces of the protrusions,
Each is independently driven to rotate. Therefore, according to the present invention, it is also possible to extract two types of independent rotational outputs from the first and second rotor portions. Further, when the first and second rotor parts are formed so as to be rotationally driven in the same direction, by connecting the first and second rotor parts, a rotational output having a double torque can be obtained. You can also

In addition to this, in the invention of claim 2, by controlling the AC voltage applied to the piezoelectric element through the electrode,
It is formed on the rotor contact surface of the block body so as to selectively generate first and second standing waves of different phases, and each of the protrusions is formed on the antinode of the first standing wave and on one side. It is formed between the nodes and between the antinode of the second standing wave and the other node.

Therefore, by controlling the applied AC voltage,
By switching the generated standing wave, it is possible to switch the rotation directions of the first and second rotor portions that are in contact with the protrusion.

The inventor has also examined the principle of rotation of this vibration motor. In this type of motor, longitudinal vibration, torsional vibration, and bending vibration are known as the types of vibration that occur. In the conventional bolted Langevin type ultrasonic motor, elliptical vibration is generated by combining longitudinal vibration and torsional vibration. It is presumed that elliptical vibration is generated.

In particular, the bending vibration is the bending vibration of the rod,
Bending vibration due to bending of the beam can be considered as two types, but in the present invention, by forming the block body into a flat shape, bending vibration due to bending of the beam is generated.

As described above, it is estimated that the vibration motor of the present invention obtains elliptical vibration by a principle different from that of the conventional Langevin type ultrasonic motor, and as a result, the rotation output capable of forward and reverse rotation is efficiently generated. In addition, the structure is simple and inexpensive.

FIG. 6 conceptually shows a state of bending vibration generated in the stator portion. The same figure (A) and (B)
FIG. 6A is a perspective view of the stator portion in which bending vibration occurs, and FIGS. 7C and 7D are side views of the stator portion shown in FIGS. There is. As shown in the figure, in the vibration motor of the present invention, a bending wave is used to generate standing waves on both end surfaces of the stator portion, that is, the first and second rotor contact surfaces, and the antinodes and nodes of the standing waves are generated. By providing a protrusion between the protrusions, elliptical vibration can be directly generated on the protrusion.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, preferred embodiments of the present invention will be described in detail with reference to the drawings.

First Embodiment FIG. 1 schematically shows a first preferred embodiment of the vibration motor according to the present invention.

The vibration motor of the embodiment has first and second rotor portions 30A and 30B and a stator portion 40.

The electrode plates 46, 4 of the stator section 40 are
8 by applying a single-phase high-frequency AC voltage to the first and second rotor contact surfaces 60A of the stator section 40,
A standing wave is generated at 60B. Then, the standing wave vibrations are directly converted into elliptical vibrations by using the protrusions 62A and 62B provided on the first and second rotor contact surfaces 60A and 60B, thereby contacting the protrusions 62A and 62B. The first and second rotor portions 30A and 30B are rotationally driven.

As described above, the vibration motor of the embodiment has the first
And two kinds of rotation outputs can be taken out from the second rotor portions 30A and 30B. When the first and second rotor portions 30A and 30B are rotationally driven in the same direction,
It is also possible to integrally connect the two rotor portions 30A and 30B and take out the rotation output having twice the usual torque.

The rotor portions 30A and 30B are provided with discs 32A and 32B which come into contact with the protrusions 62A and 62B on the rotor contact surfaces 60A and 60B at a constant pressure, and the discs 32.
The rotation output shaft 34 attached to the rotation centers of A and 32B
A and 34B are included.

The stator section 40 has two piezoelectric elements 42, 44 formed in a ring shape using a piezoelectric material such as ceramics, and a first electrode plate provided on both sides of the piezoelectric element 44. 46 and the second electrode plate 48, and a flat plate-shaped first metal block body 50 and a second metal block body 52 arranged on both sides of the piezoelectric elements 42 and 44, respectively.
And both metal block bodies 50 and 52 are connected to the piezoelectric elements 42 and 44.
And a connecting bolt 54 for connecting and fixing so as to tighten, and is formed to have a flat shape as a whole.

As the piezoelectric elements 42 and 44, for example, those obtained by polishing and removing the surfaces of silver and nickel used as electrodes during polarization after the polarization is completed are used.

Next, the structure of the stator section 40 will be described in more detail.

2 and 3, the stator portion 40 is shown. Here, FIG. 2 shows a plan view in a state where the stator portion 40 is assembled, and FIG. 3 shows an exploded perspective view thereof.

The first and second metal block bodies 50, 5
Screw holes 51, 53 are formed at the center of the second member 2, and bolt insertion holes 42a, 46a, 44 are formed at the centers of the piezoelectric element 42, the first electrode plate 46, the piezoelectric element 44, and the second electrode plate 48.
a and 48a are provided. Then, the insulating collar 5 is inserted into the bolt insertion holes 42a, 46a, 44a, 48a.
6 is inserted, and the screw portion provided on the side surface of the connecting bolt 54 is inserted into the first and second connecting bolts.
The metal block bodies 50 and 52 are screwed into the screw holes 51 and 53 formed at the center. As a result, the piezoelectric element 42,
The first metal block body 50 and the second metal block body 52 are connected and fixed to both ends of 44 so as to tighten the piezoelectric elements 42 and 44.

In this embodiment, when connecting and fixing,
Since no adhesive is used to fix the laminated surface of each member, it is possible to prevent variations in resonance frequency from one motor to another and to prevent the Q value from decreasing, thereby improving the performance and reliability of the vibration motor. You can

Further, the first electrode plate 46 is divided into 12 in the circumferential direction at intervals of 30 degrees by the slit portion 46c, and the outer peripheral portions thereof are connected to each other by the connecting portion 46b.
The diameter of the first electrode plate 46 is equal to that of the piezoelectric elements 42, 4
4 is formed to be slightly larger than the diameter of the stator portion 40.
When assembled, the outer peripheral portion and the connecting portion 46b are projected to the outside of the stator. As a result, after the assembly of the stator part 40 is completed, the connecting parts 46b are cut off, so that the divided electrode plates 46- which are electrically insulated from each other are formed.
, 46-2, ..., 46-12 can be obtained.

In particular, in this embodiment, since each of the divided electrode plates 46-1 to 46-12 can be handled as one electrode plate 46 at the time of assembling the stator, not only the assembling work becomes easy, but also each Split electrode plates 46-1 to 46-12
Can also be accurately positioned.

Further, each of the divided electrode plates 46-1 to 46-12
2, the portions protruding to the outside of the stator constitute the external connection terminals 45-1 to 45-12, and the lead wires 64-1 to 64-12 as shown in FIG.
12 will be connected. Further, an external connection terminal 49 projecting to the outside of the stator portion 40 is provided on the outer periphery of the second electrode plate 48, and as shown in FIG.
The lead wire 66 for grounding will be connected.

The twelve divided electrode plates 46-1 and 46-4
An AC voltage of A phase or B phase is selectively applied to 6-2 ... 46-12.

The piezoelectric elements 42 and 44 are divided into 12 at intervals of 30 degrees corresponding to the electrode plate 46. When two adjacent divided regions are regarded as one set of polarized regions, the adjacent polarized regions of each set are formed so that their polarization directions are opposite to each other. Here, the symbols (+, −) indicate the polarization directions of the piezoelectric elements 42 and 44, and two adjacent divided regions forming one set of polarized regions are polarized in the same direction. Then, one of the two divided regions polarized in the same direction forms the A region and the other forms the B region. The area A corresponds to a divided area of the electrode plate 46 to which the A-phase AC voltage is applied, and the area B corresponds to a divided area of the electrode plate 46 to which the B-phase AC voltage is applied. . The polarization directions of the piezoelectric elements 42 and 44 are generally opposite to each other, and the corresponding regions are simultaneously expanded and contracted.

Further, the metal block bodies 50, 5 of this embodiment
2 are connected and fixed to each other by a metal coupling bolt 54. Therefore, when the second electrode plate 48 is grounded, the second metal block body 52 and the connecting bolt 5 are automatically connected.
4, The 1st metal block body 50 becomes earth potential. Therefore, the first metal block body 50 includes the piezoelectric element 42.
Similarly to the second electrode plate 48, it will function as a ground electrode on one side of.

The coupling bolt 54 has an insulating collar 56 for the piezoelectric elements 42, 44 and the first electrode plate 4.
6 is electrically insulated.

Next, the positional relationship between the standing wave vibration generated on the rotor contact surfaces 60A and 60B and the protrusion 32 will be described.

FIG. 4A is a diagram in which the stator portion 40 is expanded in the circumferential direction. The symbol "+" indicates a region that extends when the potential of the applied AC voltage is positive, and the symbol "-" indicates that it is applied. The regions that contract when the potential of the AC voltage to be applied is positive are shown.

FIG. 6B shows the state of vibration when a single-phase AC voltage is applied to the area A. The dotted lines in the figure show the respective vibration states when only the six divided A areas are cut out, and the solid line shows the actual stator portion 40.
The whole vibration state.

In this case, the second electrode plate 48 is grounded, and the six polarized electrode plates 46-1 and 46- for the A phase are further grounded.
3 ... 46-11 is made into one group, and a common single phase alternating voltage is applied to this. As a result, the piezoelectric element 42,
The A-phase voltage application region of 44 vibrates, and the rotor contact surfaces 60A and 60B of the stator section 40 have the first portion shown in FIG.
The standing wave vibration of is generated.

Similarly, FIG. 6C shows the state of vibration when a single-phase AC voltage is applied to the B area, and the dotted lines show the respective vibrations when only the six divided B areas are cut out. The state and the solid line are actual vibration states of the entire stator section 40.

In this case, the second electrode plate 48 is grounded, and the six split electrode plates 46-2, 46-for the B phase are further grounded.
4 ... 46-11 is made into one group, and a common single phase alternating voltage is applied to this. As a result, the piezoelectric element 42,
The B-phase polarization region of 44 vibrates, and the first and second rotor contact surfaces 60A and 60B of the stator portion 40 are oscillated as shown in FIG.
The second standing wave vibration shown in (B) is generated.

As shown in FIGS. 7B and 7C, the stator portion 40 is used when a single-phase AC voltage is applied to the A-phase polarized region and when a single-phase AC voltage is applied to the B-phase polarized region. The first and second standing wave vibrations having different phases are generated on the first and second rotor contact surfaces 60A and 60B.

In order to obtain the elliptical vibration for driving the rotor from this standing wave vibration, each protrusion 32A, 32B of the embodiment has the antinode of the first standing wave shown in FIG. Is formed so as to be located in the middle of the second standing wave shown in FIG. 1C and the node on the left side thereof.
Specifically, the plurality of divided electrode plates 46-1 to 46-1
If two adjacent two are set as one set, the rotor contact surface 60 corresponding to the slit portion 46c provided at the center of each set
At the position and direction on A and 60B, the protrusions 62A,
62B is formed. Therefore, the protrusion 62 of the embodiment
Six A and 62B are provided on the rotor contact surfaces 60A and 60B at intervals of 60 degrees.

The present embodiment is constructed as described above, and its operation will be described below.

In the vibration motor of the embodiment, the piezoelectric element 42,
When a single-phase AC voltage is applied to the A-phase polarized region of 44, the first and second rotor contact surfaces 60A, 60 of the stator portion 40
In B, the first standing wave vibration shown in FIG. At this time, the first and second rotor contact surfaces 60A, 6
The protrusions 62A and 62B formed on the rotor 0B are arranged on the rotor portions 30A and 30B when the area A of the stator portion 40 extends.
To push the rotor to the right, and when it contracts, the rotor part 3
Move away from 0A and 30B. Therefore, the protrusions 62A, 62
Elliptical vibration is generated in B, and this elliptical vibration is generated in the rotor portion 30.
A and 30B are driven to rotate rightward.

As described above, according to the vibration motor of the embodiment, the two rotor portions 30A and 30B can be independently driven to rotate in the same direction.

When the rotor portions 30A and 30B are driven in the reverse direction, the single-phase AC voltage may be applied only to the B region of the stator portion 40.

As described above, according to this embodiment, by switching the region of the divided electrode plate 46 to which the AC voltage is applied,
The rotor portions 30A and 30B can be driven in forward and reverse directions. Moreover, the protrusions 62A provided on the surfaces of the rotor contact surfaces 60A, 60B do not require torsional vibration.
Since the elliptical vibration can be directly generated in 62B,
The motor has a simple structure, and the rotation output can be efficiently generated.

In the above embodiment, the two rotor parts 3
Although the case where the 0A and 30B are rotationally driven in the same direction has been described as an example, the two rotor portions 30A and 30B may be rotationally driven in different directions.

In this case, as shown in FIG. 4, each protrusion 62A is formed so as to be located at the boundary between two regions arranged in the order of A region and B region in the right direction in the figure. Further, as shown by the dotted line in the figure, each protrusion 62B is formed at the boundary position of the two areas arranged in the order of B area and A area in the right direction in the figure.

With the above configuration, when a single-phase AC voltage is applied only to the area A of the stator section 40, the stator section 40 vibrates as shown in FIG. 5 (B). As a result, the protrusions 6 provided on the first rotor contact surface 60A
2A rotationally drives the rotor unit 30A in the right direction in the drawing.
In addition, the protrusion 6 provided on the second rotor contact surface 60B
2B rotationally drives the rotor portion 30B leftward in the drawing.

As described above, according to the vibration motor of the embodiment, the rotor portions 30A and 30B can be rotationally driven in different directions.

By the way, in order to drive the above-mentioned vibration motor more efficiently, it is preferable that the frequency of the AC voltage is set to a value (resonance frequency) at which the stator section 40 causes a resonance phenomenon.

FIG. 6 conceptually shows a state of bending vibration caused by bending of a beam generated in the stator portion 40 when the entire stator portion 40 is formed into a flat shape. Same figure (A)
And (B), the stator part 40 in which bending vibration is generated.
Is shown, and FIGS. 7C and 7D are side views of the stator section 40 shown in FIGS. As shown in the figure, in the vibration motor of the present invention, it is possible to generate standing wave vibration on each rotor contact surface 60A, 60B of the stator section 40 by using bending vibration due to bending of the beam.

Next, the formula f representing the resonance frequency of the bending vibration due to the bending of the "beam" will be briefly described. This equation is roughly expressed by the following equation.

F = (2π / λ ² ) (E / ρ) ^1/2 (I 0 / A) ^1/2 λ; wavelength λ = π (D + d) / 2N (D: outer diameter, d: inner diameter, N: Wave number (number of peaks) Note that the primary resonance, the secondary resonance, the tertiary resonance, ... Have different values.

(E / ρ) ^1/2 ; speed of sound (E is Young's modulus, ρ is density) (I 0 / A) ^1/2 ; cross sectional secondary radius (I 0 is cross sectional secondary moment, A is stator part 40 Therefore, for example, D, d, and 1 of the stator portion take values as shown in FIG. 7, λ and the like have the following values, and the metal block bodies 50 and 52 are made of aluminum. Considering the vibration model, λ = 0.126 [m], (E / ρ) ^1/2 is about 500
0 [m / s], (I0 / A) ^1/2 is about 5.8 × 10
^-3 [m].

In this vibration model, the value of the resonance frequency f of the stator section 40 is about 11.5 kHz.

FIG. 8 shows a specific structure of the control circuit 80 for controlling the operation of the vibration motor.

This control circuit 80 amplifies this single-phase AC output and applies it to the split electrode plates 46-1 to 46-12. And an amplifier 92.

The control circuit 80 is turned on / off.
Switch 82, rotation direction input unit 86, rotation speed input unit 8
Including 8.

The ON / OFF switch 82 controls ON / OFF of the power supply circuit 90 and the amplifier 92.

The rotation direction input section 86 is the rotor section 30.
The rotation directions of A and 30B are selectively set, and the output signal thereof is input to the power supply circuit 90. Power supply circuit 90
Is a single-phase AC voltage A applied to one group of divided electrode plates 46-1, 46-3, ... 46-11, or the other group of divided electrode plates 4 based on this input signal.
6-2, 46-4, ... Outputs only one of the single-phase AC voltages B applied to 46-12, and the rotor section 30A,
The direction of rotation of 30B can be determined.

Further, the rotation speed input section 88 controls the amplification factor of the amplifier 92, so that the rotor section 30A,
A rotation speed of 30B can be set.

Therefore, when the ON / OFF switch 82 is turned on after setting the rotation direction and the rotation speed of the rotor sections 30A and 30B using the input sections 86 and 88, the power supply circuit 90 responds to the settings. The high frequency AC voltage of the specified frequency is output. By amplifying this by the amplifier 92 and applying it to the lead lines 64-1 to 64-12, the above-mentioned single-phase AC voltage is applied to the piezoelectric elements 42 and 44, and the rotor sections 30A and 30B can be rotationally driven. it can.

At this time, since the single-phase AC voltage applied to the piezoelectric elements 42 and 44 is controlled to the resonance frequency corresponding to the resonance mode, the input voltage is efficiently converted into the rotation output, and the rotor portion 30A, 30B can be rotationally driven.

Further, according to the vibration motor of this embodiment,
By the rotation direction input unit 86, the divided electrode plates 64-1 to 64-6
By switching the single-phase AC voltages A and B applied to 4-12, the rotation directions of the rotor units 30A and 30B can be selectively determined.

Further, in the vibration motor of the embodiment, the rotation speed of the rotor portions 30A and 30B can be controlled to an arbitrary speed by controlling the voltage value of the AC voltage using the rotation speed input portion 88.

Further, the vibration motor of the embodiment does not require torsional vibration for generating elliptical vibration, unlike the conventional Langevin type ultrasonic motor. Therefore, the piezoelectric element 4
4, 42, the first and second electrode plates 46, 48 and the first,
By simply tightening the second metal block bodies 50 and 52, the respective constituent members are connected and fixed, and the stator portion 40
Can be configured, and it becomes unnecessary to apply an adhesive to the joint surface of the constituent member. Therefore, it is possible to prevent the variation of the resonance frequency among the motors and the decrease of the Q value as in the case where the adhesive is used, and it is possible to improve the performance and reliability of the ultrasonic motor.

Further, in the present embodiment, only one type of vibration called bending vibration is used to generate the elliptic vibration, and two kinds of vibrations such as longitudinal vibration and torsional vibration are required as in the conventional ultrasonic motor. do not do. Therefore, the stator portion 40
The degree of freedom in designing, particularly, the design of the metal block bodies 50 and 52 is expanded, and the motor can be downsized.
Further, since the plate-shaped metal block bodies 50 and 52 are used, the entire vibration motor including the stator portion 40 can be flattened.

FIG. 9 shows an embodiment in which the vibration motor is attached to a housing to manufacture the product. The vibration motor of the embodiment is housed in the motor housing 106. The rotation output shafts 34A and 34B of the rotor portions 30A and 30B are supported by bearings 114 provided in the motor housing 106.

In the vibration motor of the embodiment, the stator portion 40 is attached and fixed to the housing 106 by the support portions 130 and 132 extending from the sides of the block bodies 50 and 52 in the radial direction. It is preferable that the support portions 130 and 132 be provided at the vibration nodes of the stator 40 as shown in FIG.

The rotor portions 30A and 30B are
Protrusion 6 formed on both end surfaces 60A and 60B of the stator
2A, 62B on the disk 32A, 32B is a leaf spring 1
00A and 100B and the plates 102A and 102B are configured to contact each other at a predetermined pressure. A rotation output shaft (shaft) 34A,
34B is fixed by a C ring (other than the C ring), and the rotation output shafts 34A, 34B are also rotated by the rotation of the disks 32A, 32B.

In the vibration motor having such a structure, the stator 40, particularly the metal block bodies 50 and 52 can be flattened, so that the entire housing 106 can be flattened and downsized.

Further, in FIG. 11, one rotation output shaft 34 is provided.
Shows an example of a vibration motor configured by connecting and fixing two rotor portions 30A and 30B to obtain twice the torque as compared with the vibration motor shown in FIG. The members corresponding to those of the embodiment shown in FIG. 9 are designated by the same reference numerals, and the description thereof will be omitted.

The vibration motor of the embodiment has a stator portion 4
Reference numeral 0 denotes a vibration node, which is attached and fixed to the side surface of the housing 106 by using a screw screw 122.

The coupling bolt 54 used in the stator portion 40 has a hollow structure having a rotary shaft insertion hole 54a at the center, and the common rotary output shaft 34 is inserted into the rotary shaft insertion hole 54a. . The rotation output shaft 34 is
A bearing 114 provided in the rotary shaft insertion hole 54a of the coupling bolt 54 and a bearing 114 provided in the center of the upper portion of the housing 106 are rotatably supported.

The common rotation output shaft 34 is fixed to the disc 32A of the one rotor portion 30A via a detent, and is also fixed to the disc 32B of the other rotor portion 30B via a detent. ing. As a result, the rotation output of the two rotor portions 30A and 30B is common to the rotation output shaft 3
4 is output, the torque of the rotation output shaft 34 is doubled.

FIG. 12 shows a modification of this embodiment. In the above embodiment, the piezoelectric elements 42 and 44 are divided into a plurality of regions, two adjacent divided regions are set as one set of polarization regions, and the polarization regions of each set are formed so that their polarization directions are different from each other. There is. On the other hand, in this modified example, the two piezoelectric elements 42 and 44 formed in a ring shape are polarized in the same direction, and the two piezoelectric elements 42 and 4 are polarized.
4 are three-dimensionally arranged so that their polarization directions are different from each other. Further, the first electrode plate 46 is divided into 6 at intervals of 60 °, and each connecting portion 46b is cut after the stator portion 40 is assembled. Since the configuration other than this is the same as that of the above-described embodiment, the description thereof is omitted here.

FIG. 13 shows the operating principle of the vibration motor thus formed.

FIG. 11A is a diagram showing the stator portion 40 developed in the circumferential direction, and shows a state before an AC voltage is applied. Two adjacent divided electrode plates are set as one set, and each region of the stator portion 40 corresponding to one divided electrode plate 46-1, 46-3, 46-5 of each set is an A region, and the other divided electrode plate of each set is divided. Each area of the stator portion 40 corresponding to the electrode plates 46-2, 46-4, 46-6 is defined as an area B.

The first rotor contact surface 60 of the stator portion 40
On A, three protrusions 62A are formed at the boundary between the A region and the B region of each set, and the rotor portion 30A is in contact with each of these protrusions 62A. Similarly, the second stator portion 40
On the rotor contact surface 60B of the above, three protrusions 62B are formed at the boundary between the A region and the B region of each set.
Is in contact with the rotor portion 30B.

FIG. 6B shows a vibration state when the single-phase AC voltage is applied only to the area A of the stator section 40 described above. Projection 62A of the first rotor contact surface 60A
Focusing on the A region side of the end face, when the A region of the stator portion 40 extends, it acts to push the rotor portion 30A to the right, and when it contracts, it separates from the rotor portion 30A. Therefore, elliptical vibration is generated on the area A side of the end face of the protrusion 62A, and this elliptical vibration drives the rotor portion 30A to rotate rightward in the drawing.

Also, focusing on the B area side of the end surface of the protruding portion 62B of the second rotor contact surface 60B, A of the stator portion 40
It acts so as to push out the rotor portion 30A having the extended region to the left, and when it contracts, it separates from the rotor portion 30A. Therefore, elliptical vibration is generated on the B area side of the end surface of the protrusion 62B, and this elliptic vibration drives the rotor portion 30B to rotate leftward in the drawing.

As described above, according to the vibration motor of the embodiment, the rotor portion 30A and the rotor portion 30B can be rotationally driven in opposite directions to obtain two types of rotational outputs.

When the rotor portions 30A and 30B are driven in the reverse direction, the single-phase AC voltage may be applied only to the B region of the stator portion 40.

As described above, according to this embodiment, by applying the single-phase AC voltage to the stator portion 40, the two rotor portions 30A and 30B can be rotationally driven in opposite directions.

In the embodiment shown in FIG. 13, the two rotor portions 30A and 30B are rotationally driven in different directions, but the two rotor portions 30 are not shown.
It is also possible to form A and 30B so as to rotate in the same direction.

FIG. 14 shows the operating principle in this case. In this case, as shown in FIG. 7A, each protrusion 6 is formed on the first rotor contact surface 60A so as to be located at the boundary between the two regions arranged in the right direction in the drawing in the order of the A region and the B region.
2A is formed. Further, each protrusion 62B is formed on the second rotor contact surface 60B so as to be located at the boundary between two areas arranged in the order of the area B and the area A in the right direction in the drawing.

With the above structure, as shown in FIG. 9B, when a single-phase AC voltage is applied only to the area A of the stator 40, the protrusion 62A provided on the first rotor contact surface 60A As in the embodiment shown in FIG. 4, the rotor portion 30A is driven to rotate rightward in the drawing. Also, the second
The protrusion 62B provided on the rotor contact surface 60B of
Focusing on the B region side, elliptical vibration in the same direction as the protruding portion 62A is generated, and this elliptical vibration drives the rotor portion 30B to rotate rightward in the drawing.

As described above, according to the vibration motor of the embodiment, the rotor portions 30A and 30B can be rotationally driven in the same direction.

When the rotor portions 30A and 30B are driven in the reverse direction, the single-phase AC voltage may be applied only to the B region of the stator portion 40.

In FIG. 15, when the electrode plate 46 is changed from the above-mentioned 12-division, 6-division to 4-division, the electrode plate 46 and the corresponding projections 62 on the first metal block 50 are formed.
The state of is shown. Since the protrusions 62A and 62B are formed corresponding to the vicinity of the boundary between the adjacent divided electrode plates, when the electrode plate 46 is divided into four, the protrusions 62A will be two places and the protrusions 62B will also be two places. . Other configurations are the same as those shown in FIG. 3 or FIG. 9, and the rotor portion can be driven in the normal rotation or the reverse rotation by selectively applying the AC voltages A and B.

Second Embodiment FIG. 16 shows a second preferred embodiment of the present invention. It should be noted that the vibration motor of the present embodiment has a rotor contact surface
The basic structure is the same as that of the first embodiment shown in FIGS. 1 to 3 except the arrangement of the protrusions 62A and 62B provided on the A and 60B, and therefore the description thereof is omitted here.

The feature of this embodiment is that by applying an AC voltage to the entire surfaces of the piezoelectric elements 42 and 44, the stator portion 40
To oscillate the whole area of. That is, in the above-described first embodiment, when the A region of the stator portion 40 is vibrated, the B region is in a rest state, and when the B region is vibrated, the A region is in a rest state. Therefore,
At the time of driving, half of the area of the stator portion 40 is always idle, and this embodiment improves the driving efficiency.

FIG. 16A shows the stator portion 4 of the embodiment.
A diagram of 0 developed in the circumferential direction is shown.

Six radial projections 62A and 62B are formed on the rotor contact surfaces 60A and 60B of the stator 40 of the embodiment. These protrusions 62
A and 62B are formed corresponding to the positions near the center of the A area of the piezoelectric elements 42 and 44.

FIG. 11B shows the state of vibration when the A-phase AC voltage is applied to the A region. The dotted lines in the figure show the respective vibration states when only the six divided A areas are cut out, and the solid line shows the actual stator portion 40.
The whole vibration state.

Similarly, FIG. 7C shows the state of vibration when an AC voltage of the B phase having the same phase as the A phase is applied to the B area, and the dotted line shows only the six divided B areas. Each vibration state, the solid line is the actual stator part 4
0 is the entire vibration state. It should be noted that FIG. 3D shows a vibration state in the case where a B'phase AC voltage having a phase opposite to that of the B phase is applied to the B region.

In the same figure (E), the A phase and B phase are shown in the A region and B region, respectively.
When the phase alternating voltage is applied simultaneously, the stator unit 40
Shows the first standing wave vibration appearing in FIG. This is a superposition of the vibration waveforms shown in (B) and (C) of the same figure, and the peak (antinode) of the vibration of the first standing wave is in the A region polarized in the same direction. Appears near the boundary of the B area.
Therefore, the protrusions 62A and 62B formed on the first and second rotor contact surfaces 60A and 60B are located in the middle of the node and the node of the first standing wave. As a result,
Elliptical vibration appears on the end faces of the protrusions 62A and 62B.
As shown in FIG. 7 (A), the rotor portions 30A and 30B are rotationally driven leftward.

FIG. 16F shows the state of the second standing wave vibration that appears in the stator section 40 when the A-phase and B'-phase AC voltages are applied simultaneously. This is a superposition of the vibration waveforms shown in FIGS. (B) and (D), and the peak of the vibration of this second standing wave is the boundary between the regions A and B polarized in the opposite direction. Appears in the vicinity. Therefore, the protrusions 62A and 62B are located between the antinode and the node of the second standing wave, and FIG.
Compared with the vibration state shown in (1), the peak of the standing wave and the relative positions of the protrusions 62A and 62B are opposite. Therefore, the elliptic vibration in the opposite direction to the elliptic vibration shown in FIG. 14A appears on the protrusions 62A and 62B, and the rotors 30A and 30B are driven in the reverse direction as shown in FIG. 17B. Become.

As described above, each protrusion 62 of the embodiment is located between the antinode of the first standing wave shown in FIG. 16 (E) and the node on one side, and is also shown in FIG. 16 (F). It is formed so as to be located between the antinode of the second standing wave and the node on the other side. Therefore, A phase and B applied to each region of the piezoelectric elements 42 and 44
By controlling the application state of the alternating voltage of the phase,
The first standing wave shown in FIG. 16E and the second standing wave shown in FIG.
It is possible to drive A and 30B in the forward and reverse directions.

In particular, according to the present embodiment, compared with the first embodiment, the whole area (A area and B area) of the stator section 40 is vibrated at the same time, and the rotor sections 30A, 30B are driven to rotate, so that 2 A large output torque can be obtained from the one rotor section 30A, 30B.

The specific structure of the control circuit 80 for controlling the operation of the vibration motor is almost the same as that shown in FIG. In this case, the power supply circuit 90 simultaneously outputs two AC voltages (A phase, B phase) having the same phase, or two AC voltages having opposite phases (A phase, B ′ phase).
Can be simultaneously output, and this selection operation is instructed by the rotation direction input unit 86.

In the embodiment shown in FIGS. 16 and 17, 2
Although the description has been given by taking as an example the one in which the two rotor portions 30A and 30B are rotationally driven in the same direction, the present embodiment is not limited to this.
The two rotors 30A and 30B may be formed so as to be rotationally driven in different directions.

FIG. 18 schematically shows the vibration motor thus constructed.

FIG. 13A is a diagram showing the stator portion 40 developed in the circumferential direction. On the first rotor contact surface 60A of the stator 40, a plurality of protrusions 62A are formed near the center of the area A of the piezoelectric element 42. Further, on the other rotor contact surface 60B, a plurality of protrusions 62B are formed near the center of the region B of the piezoelectric element 42. 16B to 16D.
Since it is the same as (E), description thereof will be omitted.

FIG. 13E shows the first standing wave vibration appearing in the stator section 40 when the AC voltage is applied to the A phase and the B phase at the same time. Peak appears near the boundary between the A and B regions polarized in the same direction. Therefore, an elliptical vibration is generated between the end face of the protrusion 62A provided corresponding to the central portion of the A region in contact with the peak of this vibration and the end face of the protrusion 62B provided near the center of the B region. Appears in the opposite direction. Therefore, FIG.
As shown in (A), the rotor portions 30A and 30B are rotationally driven in different directions.

FIG. 18F shows the state of the second standing wave vibration that appears in the stator section 40 when the A-phase and B'-phase AC voltages are applied at the same time. In this case, the elliptical vibrations appearing on the end faces of the protrusions 62A and 62B are in the opposite direction to the case shown in FIG.
As shown in FIG.
It is driven to rotate in the opposite direction to (A).

As described above, by controlling the application states of the A phase and the B phase applied to the respective regions of the piezoelectric elements 42 and 44, the two rotor portions 30A and 30B can be efficiently driven in the forward or reverse direction. it can.

FIG. 20 shows a modification of the first and second embodiments. Piezoelectric element 4 of the first and second embodiments
In Nos. 2 and 44, as shown in FIG. 3, two divided regions polarized in the same polarity form one set of polarized regions, and each set of polarized regions is alternately polarized in the opposite direction in the rotor rotation direction. Has been formed. On the other hand, in the piezoelectric elements 42 and 44 of the modified example shown in FIG. 20, one divided region constitutes one set of polarized regions, and these polarized regions are alternately polarized in opposite directions in the rotor rotation direction. Is formed. Even when formed in this way, the electrode plate 46 is formed in the same manner as in the first and second embodiments, and the divided electrode plates 46-1, 4 of the electrode plate 46 are formed.
By dividing each polarization region into two-phase voltage application regions of A region and B region by 6-2, it is possible to obtain the same effects as those of the first and second embodiments.

In the piezoelectric elements 42 and 44 of this modification, for example, the silver or nickel surface used as an electrode during polarization needs to be removed by polishing after the polarization is completed.

Third Embodiment FIG. 21 shows a preferred third embodiment of the present invention. The members corresponding to those in the first and second embodiments described above are designated by the same reference numerals, and the description thereof will be omitted.

The electrode plate 46A of the present embodiment is 6 degrees apart every 60 degrees.
It is divided, and an A-phase AC voltage is applied to each divided region. Similarly, the electrode plate 46B is divided into six 60 degrees, and a B-phase AC voltage is applied to each divided region.
An insulating plate 43 is sandwiched between these two electrode plates 46A and 46B so that AC voltage of A phase and B phase can be separately applied to each electrode plate.

The piezoelectric element 42 is divided into six parts at intervals of 60 degrees corresponding to one electrode plate 46A, and is formed so that the polarization directions of the adjacent divided regions are opposite to each other. Also,
The piezoelectric element 44 is divided into six parts every 60 degrees corresponding to the other electrode plate 46B, and is formed so that the polarization directions of the adjacent divided regions are opposite. Piezoelectric elements 42 and 44
Are three-dimensionally arranged so that the phases of the polarized regions are shifted from each other by 30 degrees.

The metal block bodies 50 and 52 have six radial projections 62 on their outer end surfaces 60A and 60B, respectively.
A-1, 62A-2 ... 62A-6 and 62B-1, 6
2B-2 ... 62B-6. Each of these protrusions 62A
-1, 62A-2 ... 62A-6 and 62B-1, 62
As shown in FIG. 22 (A), B-2 ... 62B-6 are located corresponding to the vicinity of the center of the overlapping region of the polarization regions of the piezoelectric elements 42 and 44.

FIG. 22 shows the outline of the operating principle of this embodiment.

FIG. 13A is a diagram in which the stator portion 40 is developed in the circumferential direction. The symbol “+” indicates a region that extends when the potential of the applied AC voltage is positive, and the symbol “−” indicates that it is applied. The regions that contract when the potential of the AC voltage to be applied is positive are shown.

FIG. 11B shows the first generated in the stator section 40 when the A-phase single-phase AC voltage is applied to the electrode plate 46A.
2C shows the second standing wave vibration generated in the stator portion 40 when the B-phase single-phase AC voltage is applied to the electrode plate 46B.

As shown in the figure, each protrusion 62A-1,
62A-2 ... 62A-6, 62B-1, 62B-2 ... 6
22B-6 is located between the antinode of the first standing wave shown in FIG. 22B and the node on one side, and the antinode of the second standing wave shown in FIG. It will be located between the side nodes.

Therefore, as shown in FIG. 7B, when the first standing wave vibration is generated by applying the single-phase AC voltage only to the area A of the stator portion 40, the area A of the stator portion 40 expands. , The protrusions 62A-1, 62A-3, 62A-5 and 6 so as to push the rotor portions 30A, 30B to the left.
2B-2, 62B-4, 62B-6 act. When the area A of the stator portion 40 contracts, the rotor portion 30
A, 30B to protrusions 62A-1, 62A-3, 62A
-5 and 62B-2, 62B-4, 62B-6 are separated, but conversely, other protrusions 62A-2, 62A-4, 62A
-6 and 62B-1, 62B-3, 62B-5 act so as to push the rotor portions 30A, 30B to the left. In this way, each protrusion 62A-1, 62A-2
... 62A-6 and 62B-1, 62B-2 ... 62B-
Elliptic vibration is generated in 6, and this elliptic vibration drives the two rotor portions 30A and 30B to rotate leftward.

On the contrary, as shown in FIG. 7C, when the second standing wave vibration is generated by applying the single-phase AC voltage only to the area B of the stator section 40, When the B area of the rotor is extended, the protrusions 62A-2, 62A-4, 62A are pushed out so as to push the rotor portions 30A, 30B to the right.
-6 and 62B-1, 62B-3, 62B-5 work. When the region b of the stator portion 40 contracts, the rotor portions 30A and 30B extend from the protrusion portions 62A-2 and 62A-.
4, 62A-6 and 62B-1, 62B-3, 62B
-5 separates, but conversely the other protrusions 62A-1, 62A-
3, 62A-5 and 62B-2, 62B-4, 62B
-6 acts so as to push the rotor portions 30A and 30B rightward. In this way, each protrusion 62A-1,
62A-2 ... 62A-6 and 62B-1, 62B-2
... 62B-6 has an elliptical vibration, and this elliptic vibration is 2
The two rotor portions 30A and 30B are rotationally driven in the right direction.

As described above, according to this embodiment, the rotor portions 30A and 30B can be driven in the forward and reverse directions by switching the regions of the divided electrode plates 46A and 46B to which the AC voltage is applied. Moreover, the projection 6 provided on the surfaces of the rotor contact surfaces 60A and 60B does not require torsional vibration.
Since the elliptical vibration can be directly generated in 2A and 62B, the motor configuration is simple and the rotation output can be efficiently generated.

Fourth Embodiment Next, a preferred fourth embodiment of the present invention will be described. In the vibration motor of the embodiment, the arrangement of the protrusions 62A and 62B formed on the rotor contact surfaces 60A and 60B is different from that of the third embodiment, and the other basic configuration is the same as that of the third embodiment. Since it is the same, detailed description thereof is omitted here.

In the vibration motor of the third embodiment, when the area A of the stator portion 40 is vibrated, the area B is in a rest state, and when the area B is vibrated, the area A is in a rest state. It is in. Therefore, at the time of driving, half the area of the stator portion 40 is always stopped. On the other hand, the feature of this embodiment resides in that the AC voltage is applied to the entire surfaces of the piezoelectric elements 42 and 44 to vibrate the entire area of the stator section 40 and improve the driving efficiency thereof.

FIG. 23A shows a state where the stator portion 40 of the vibration motor of the embodiment is expanded in the circumferential direction.

As shown in the figure, the stator portion 40 of the embodiment
Has a plurality of radial protrusions 62A, 62B on its rotor contact surfaces 60A, 60B. These projections 62A,
62B is located corresponding to the vicinity of the center of each divided area A of the piezoelectric element 42.

In the figure, the symbol "+" represents a region that extends when the potential of the applied AC voltage is positive, and the symbol "-" represents a region that contracts when the potential of the applied AC voltage is positive. There is.

FIG. 13B shows the vibration state of the piezoelectric element 42 when the A-phase AC voltage is applied to the electrode plate 46A, and FIG. 13C shows the B-phase AC voltage when the electrode plate 46B is applied. The respective vibration states of the piezoelectric element 44 are shown. Further, FIG. 3D shows the vibration state of the piezoelectric element 44 when an AC voltage of B'phase, which is the opposite phase of the B phase, is applied to the electrode plate 46B.

FIG. 13E shows the state of the first standing wave vibration that appears in the stator section 40 when the A-phase and B-phase AC voltages are simultaneously applied. The relative position between the peak of wave vibration and the protrusions 62A and 62B is shown in FIG.
6 (E) is the same as that of the second embodiment. Therefore, elliptical vibration is generated on the protrusions 62A and 62B, and the two rotors 30A and 30B can be rotationally driven leftward.

Further, (F) of the figure shows the state of the second standing wave vibration that appears in the stator section 40 when the AC voltages of the A phase and the B'phase are simultaneously applied. The relative position between the peak of the standing wave vibration and the protrusions 62A and 62B is also the same as that of the second embodiment shown in FIG. 16 (F). Therefore, elliptical vibrations in opposite directions are generated on the protrusions 62A and 62B, and the rotor portions 30A and 30B can be driven in the reverse direction to the right.

As described above, the two rotor portions 30A and 30B can be driven in the forward direction by applying the A-phase and B-phase AC voltages, and the A-phase and B'-phase AC voltages can be applied. The two rotor sections 30A and 30B can be driven in reverse. Further, the two piezoelectric elements 42 and 44 are
Since the AC voltage is constantly applied and in a vibrating state, it is possible to perform efficient rotational driving.

FIG. 24 shows a modification of this embodiment. The feature of this modified example is as shown in FIG.
A plurality of protrusions 62A provided on the rotor contact surface 60A
Is located near the center of each polarization region A of the piezoelectric element 42,
A plurality of protrusions 6 provided on the other rotor contact surface 60B
0B is located near the center of each polarization region B of the piezoelectric element 44.

Thus, the electrode plates 46A, 46B are
When the single-phase AC voltages of the B-phase and the B-phase are applied at the same time, the first standing wave vibration that is a combination of the A-phase vibration and the B-phase vibration appears in the stator section 40, as shown in FIG. . The vibration peak of the first standing wave and the protrusions 62A, 62
The relative position to B is the same as that of the embodiment shown in FIG. Therefore, two types of elliptical vibrations directed in different directions are generated on the protrusions 62A, 62B, and the two rotors 30A, 30B can be rotationally driven in different directions.

Further, FIG. 24F shows the state of the second standing wave vibration that appears in the stator section 40 when the A-phase and B'-phase AC voltages are applied simultaneously. The relative position between the peak of the second standing wave vibration and the protrusions 62A and 62B is also the same as that of the embodiment shown in FIG. Therefore,
On the protrusions 62A and 62B, elliptical vibrations in the opposite direction to the case shown in FIG.
Can be reversely driven in a direction different from that shown in FIG.

The present invention is not limited to the above embodiments, and various modifications can be made within the scope of the gist of the present invention.

For example, in each of the embodiments described above, the electrode plate 4
6 and the metal block body 50 and the like need to be positioned in the circumferential direction. As a method for this positioning, for example, a groove may be formed on the outer peripheral portion of the collar 56, and a protrusion may be provided on the electrode plate 46 or the like facing the groove. FIG. 25 shows a structure in which a positioning structure is added to the stator section 40 shown in FIG. Six grooves 56a are formed on the outer peripheral portion of the collar 56, and protrusions 51 corresponding to the grooves are provided on the inner peripheral portions of the electrode plate 46 and the metal block body 50, respectively. By assembling the stator portion 40 by fitting the groove 56a and the protrusion 51, the slit portion 4 of the electrode plate 46 is
The protrusion 62 formed on the end surface of the metal block body 50 can be arranged at a position corresponding to 6c.

Further, in the above-described first to fourth embodiments, the first
The case where six or twelve protrusions 62 are provided on the end surface of the metal block body 50 has been described as an example. However, the number of divisions of the electrode plate and the piezoelectric element and the number of polarizations may be changed to change the number of protrusions. You may

Further, according to the above embodiment, the block body 5
The case where the connecting bolt 54 is used for connecting and fixing 0 and 52 has been described as an example. However, unlike the conventional Langevin type ultrasonic motor, since torsional vibration is not required in the present invention, a connecting member other than the bolt is used. The block bodies 50 and 52 may be connected and fixed together.

[0143]

As described above, according to the present invention, the degree of freedom in design is large, the structure is simple, the flattening is possible, and the rotation output can be efficiently generated from the two rotor portions. A vibration motor capable of bidirectional rotation can be provided if necessary.

Particularly, in the present invention, since the flat block body is used, the vibration motor as a whole can be flattened and downsized.

In addition to this, according to the present invention, since the bending vibration is generated in the stator portion and the elliptical vibration is directly generated on the protrusion portion, the rotor portion is driven. A motor can be realized.

[Brief description of drawings]

FIG. 1 is an overall explanatory view of a first preferred embodiment of a vibration motor according to the present invention.

2 is a schematic plan view showing a stator portion of the vibration motor shown in FIG. 1. FIG.

FIG. 3 is an exploded perspective view of a stator portion shown in FIG.

FIG. 4 is an explanatory diagram showing a generation state of elliptical vibration according to the first embodiment.

FIG. 5 is an explanatory diagram of an operation principle of the first embodiment.

FIG. 6 is an explanatory diagram of bending vibration generated in a stator portion.

FIG. 7 is a diagram showing an example of a vibration model of a stator section.

8 is a block diagram of a control circuit used in the vibration motor shown in FIG.

FIG. 9 is a cross-sectional view of an embodiment in which a housing and the like are attached to the vibration motor.

FIG. 10 is an explanatory diagram showing a bending vibration generated in a stator portion and a node portion of the bending vibration.

FIG. 11 is a cross-sectional view of another example in which a housing and the like are attached to the vibration motor.

FIG. 12 is an exploded perspective view of a modification of the stator portion of the first embodiment.

13 is an explanatory diagram of an operation principle of a vibration motor using the stator section shown in FIG.

14 is an explanatory diagram of an operating principle of a vibration motor using the stator section shown in FIG.

FIG. 15 is an explanatory diagram of another modification of the stator section of the embodiment.

FIG. 16 is an explanatory diagram of a second preferred embodiment of the vibration motor according to the present invention.

17 is an operation explanatory view of the vibration motor shown in FIG.

18 is an explanatory diagram of a modification of the vibration motor shown in FIG.

FIG. 19 is an operation explanatory diagram of the modified example shown in FIG. 18;

FIG. 20 is a schematic explanatory view showing a modified example of the stator portion of the second embodiment.

FIG. 21 is an exploded perspective view of a stator portion according to a third embodiment.

FIG. 22 is an explanatory diagram of an operation principle of the third embodiment.

FIG. 23 is an explanatory diagram of a vibration motor according to a fourth embodiment of the present invention.

FIG. 24 is an explanatory diagram of a modification of the fourth embodiment.

FIG. 25 is a configuration diagram when a groove is provided in a collar and an electrode plate or the like is positioned.

FIG. 26 is an explanatory diagram of a conventional bolted Langevin type ultrasonic motor.

[Explanation of symbols]

 30A, 30B Rotor part 40 Stator part 42,44 Piezoelectric element 43 Insulating plate 46 First electrode plate 48 Second electrode plate 50 First metal block body 52 Second metal block body 54 Coupling bolt 60A, 60B Rotor contact Surface 62A, 62B Projection 80 Control circuit

Claims (7)

[Claims] 1. A stator section having first and second rotor contact surfaces; a first rotor section and a second rotor section that are driven to rotate by contacting the first and second rotor contact surfaces; In the vibration motor, the stator section forms a plurality of voltage application regions on the surface of the piezoelectric element at predetermined intervals along the rotation direction of the rotor section on the surface of the piezoelectric element. An electrode and a flat first block body and a second block body that are attached and fixed to both sides of the electrode so as to sandwich the piezoelectric element, and have outer end surfaces thereof as the first and second rotor contact surfaces; A plurality of protrusions provided on the first and second rotor contact surfaces, and by applying an AC voltage to the voltage application region of the piezoelectric element, the first and second rotors of each block body A standing wave is generated on the contact surface. , The constant by providing the projecting portion between the standing wave antinodes and nodes, an elliptical vibration is generated on the projecting portion, the first and second contact with the protrusion
A vibration motor, characterized in that the rotor part of the motor is rotationally driven. 2. A stator portion having first and second rotor contact surfaces, a first rotor portion and a second rotor portion which are in contact with the first and second rotor contact surfaces and are driven to rotate, And a piezoelectric element that generates vibration, an electrode that forms a plurality of voltage application regions on a surface of the piezoelectric element along a rotation direction of the rotor section, and the piezoelectric element. A flat first block body and a second block body which are fixedly mounted on both sides of the element so as to sandwich the element and whose outer end surfaces are the first and second rotor contact surfaces; and the first and second block bodies. A plurality of protrusions provided on the rotor contact surface of the block body, and different from the first and second rotor contact surfaces of the block bodies by switching control of the AC voltage applied to the piezoelectric element via the electrode. First standing of phase And a second standing wave, the plurality of protrusions are located between an antinode of the first standing wave and a node on one side, and the second standing wave is formed. It is formed so as to be positioned between the antinode of the standing wave and the node on the other side, and by controlling the switching of the applied AC voltage and selecting the standing wave to be generated, the rotor portion in contact with the protrusion is Vibration motor characterized by switching the rotation direction. 3. The piezoelectric element according to claim 2, wherein the piezoelectric elements are polarized in the same direction, and the electrodes have a plurality of voltage application regions formed on a surface of the piezoelectric element along a rotation direction of a rotor portion. By dividing each other into two voltage application groups and selectively applying a single-phase AC voltage, the first and second standing wave vibrations are applied to the first and second rotor contact surfaces of the block body. The plurality of protrusions are formed between the antinodes of the first standing wave and the nodes on one side, and the antinodes of the second standing wave and the other side of the second standing wave. Characterized in that it is formed so as to be located between the nodes, and controls the switching of the applied AC voltage and selects the standing wave to be generated, thereby switching the rotation direction of each rotor portion in contact with the protrusion. Vibration motor to. 4. The piezoelectric element according to claim 2, wherein the piezoelectric elements are alternately polarized along the rotation direction of the rotor portion in opposite directions, and the electrodes form a plurality of phases on the surface of each polarization region of the piezoelectric element. Voltage application regions of the electrode, each voltage application region of the electrode is divided into a plurality of voltage application groups, each of which is a common-mode voltage application region, and a single-phase AC voltage is selectively applied to each voltage application group. Is applied to selectively generate first and second standing wave vibrations on the first and second rotor contact surfaces of the block body. Is formed between the antinode of the standing wave and the node on one side, and between the antinode of the second standing wave and the node on the other side. , By selecting the standing wave to be generated, A vibration motor, wherein the rotation direction of each of the rotor portions in contact with the protrusion is switched. 5. The piezoelectric element according to claim 2, wherein the piezoelectric elements are alternately polarized along the rotation direction of the rotor portion in opposite directions, and the electrodes form a plurality of phases on the surface of each polarization region of the piezoelectric element. Voltage application regions of the electrode, each voltage application region of the electrode is divided into a plurality of voltage application groups having one in-phase voltage application region of each polarization region as a set, and each voltage application region is simultaneously applied to each of the voltage application groups. By applying a multi-phase AC voltage, the block body is formed so as to selectively generate first and second standing wave vibrations on the first and second rotor contact surfaces, and the plurality of protrusions are formed. The AC voltage is formed so as to be located between the antinode of the first standing wave and the node on one side and between the antinode of the second standing wave and the node on the other side. Switching control to generate the standing wave A vibration motor, wherein the rotation direction of each rotor portion in contact with the protrusion is switched by selection. 6. The piezoelectric element according to claim 2, wherein the piezoelectric element includes a plurality of piezoelectric elements that are alternately polarized in opposite directions along a rotation direction of a rotor portion, and the plurality of piezoelectric elements are in a phase of a polarization region. Are arranged three-dimensionally so that the electrodes are provided so as to correspond to each of the plurality of piezoelectric elements,
The first and second rotors of the block body include a plurality of electrodes each having a polarization region of a corresponding piezoelectric element as a voltage application region, and applying a single-phase AC voltage to any one of the plurality of electrodes. The contact surface is formed to selectively generate first and second standing wave vibrations, and the plurality of protrusions are located between an antinode of the first standing wave and a node on one side. Is formed so as to be positioned between the antinode of the second standing wave and the node on the other side, by switching control of the applied AC voltage and selecting the standing wave to be generated, A vibration motor, characterized in that the rotation direction of each rotor portion in contact is switched. 7. The piezoelectric element according to claim 2, wherein the piezoelectric element includes a plurality of piezoelectric elements that are polarized alternately in opposite directions along a rotation direction of a rotor portion, and the plurality of piezoelectric elements are arranged in a phase of a polarization region. Are arranged three-dimensionally so that the electrodes are provided so as to correspond to each of the plurality of piezoelectric elements,
A plurality of electrodes having respective polarization regions of corresponding piezoelectric elements as voltage application regions are included, and by applying a multi-phase AC voltage to the plurality of electrodes, the first and second rotor contact surfaces of the block body are applied. The plurality of protrusions are formed to selectively generate first and second standing wave vibrations, and the plurality of protrusions are located between an antinode of the first standing wave and a node on one side. 2 is formed so as to be located between the antinode of the standing wave and the node on the other side. By switching control of the alternating voltage to be applied and selecting the standing wave to be generated, each of the contact points with the protrusion A vibration motor characterized by switching the rotation direction of a rotor section.