JPH04355677A - Ultrasonic wave actuator for conveyer and conveyer thereof - Google Patents

Abstract

PURPOSE:To simplify a drive circuit without utilizing two vibration modes and to support a vibrator in a stable state. CONSTITUTION:A main vibrator 21 is formed of an elastic material, two nodes of a vibration are formed at the time of exciting, and a secondary longitudinal deflecting vibration is generated. Subvibrators 22, 23 formed of elastic materials integrally protrude from both ends of the vibrator 21, a node of a vibration is formed at a connecting point to the vibrator 21 at the time of exciting, and a primary longitudinal deflecting vibration is generated. And, a piezoelectric device is mounted at the vibrator 21. Accordingly, when an AC voltage is applied to the piezoelectric device in a state that the two nodes of the vibration of the vibrator 21 are supported, secondary longitudinal deflecting vibration is generated at the vibrator 21, the primary longitudinal deflecting vibration is generated at the subvibrators 22, 23, thereby transferring a material to be transferred.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention is applicable to paper sheets stacked in multiple layers in storage units of printers, copying machines, printing machines, facsimile machines, automatic cash handling machines, etc., and cards used in card readers. The present invention relates to a transport ultrasonic actuator and a transport device for transporting objects.

0002

[Prior Art] Conventionally, when transferring an object such as paper inside a printer, copying machine, printing machine, facsimile machine, automatic cash handling machine, etc., a roller is rotated by an electromagnetic motor. The rollers are driven to rotate, and the object to be transported is sent between both rollers so that the object is transported by friction.

[0003] On the other hand, a conveyance device that conveys paper using ultrasonic vibration uses a piezoelectric ceramic vibrator that is shaped like a round bar and has strip electrodes on its outer circumferential surface. (Refer to pages 3 to 13 of the collection of lecture papers by the Japan Industrial Technology Association, "Ultra-precision positioning and solid-state actuators"). The vibrator used in the above-mentioned conveyance device also serves as the drive shaft of the conveyance mechanism, and has cylindrical rubber rollers (movable elements) at both ends of the vibrator to constitute an ultrasonic motor. The ultrasonic motor is used to transport paper and cards.

Next, the vibration operation of the vibrator will be explained. FIG. 2 is a perspective view of a piezoelectric ceramic vibrator, and FIG. 3 is a diagram showing the relationship between applied voltage and generated strain. (A) of FIG. 3 shows a state in which distortion is generated in the vertical direction, and (B) shows a state in which distortion is caused in the horizontal direction. In FIG. 2, numeral 1 indicates strip electrodes, and four strip electrodes are arranged in one vibrator. Further, 2 is a piezoelectric ceramic round bar. The above four strip electrodes 1 are shown in FIGS. 3A and 3B.
When adjacent strip electrodes 1 are connected to each other and an alternating current voltage is applied in two ways as shown in the figure, they are polarized as shown by the dashed arrows and an electric field is generated as shown by the solid arrows. and,
In method (A), the upper and lower parts of strip electrode 1 are (B
) method, the left and right parts repeatedly expand and contract in the length direction.

FIG. 4 is a diagram showing a state in which the device is excited in a vibration mode. In the figure, reference numeral 1 denotes a strip electrode, and when an alternating current voltage whose frequency is equal to the resonance frequency of the bending vibration of the piezoelectric ceramic rod 2 is applied, the vibrator vibrates in the direction of the arrow. FIG. 5 is a drive circuit diagram for continuous excitation.

In the figure, 1a to 1d are strip electrodes, and T1 and T2 are transformers. Above strip electrode 1
When AC voltage is applied to a to 1d with a phase difference of 90°, two expansion and contraction operations, that is, bending vibrations are continuously excited. The combination of these two bending vibrations generates elliptical motion at both ends of the vibrator. That is, the conventional ultrasonic motor utilizes this elliptical motion to rotate cylindrical rubber rollers installed at both ends of the vibrator.

[0007] A paper or card conveyance device will be explained based on FIGS. 6 and 7. FIG. 6 is a perspective view of a single point external type ultrasonic motor, and FIG. 7 is a perspective view of a single point internal type ultrasonic motor. In FIG. 6, 11 is a support ring, 12 is a vibrator, 13 is a drive roller, and 14 is an auxiliary roller. The edge portion of the end of the vibrator 12 is circumscribed at one point on the outside of the drive roller 13, and when an elliptical motion occurs at both ends of the vibrator 12, the drive roller 13 rotates and the auxiliary roller 14 rotates. Assist the rotation. Paper or cards are conveyed while being sandwiched between a drive roller 13 and an auxiliary roller 14.

In FIG. 7, both ends of the vibrator 12 are rotated by contacting the inner peripheral surface of a cup-shaped drive roller 13 that is rotatably supported. The elliptical motion generated at both ends rotates the drive roller 13 that is inscribed with the vibrator 12 at one point, and the auxiliary roller 14 assists the rotation. For paper and cards, drive roller 13 and auxiliary roller 14
It is transported between the two.

[0009] Since the above-described conveyance device uses an ultrasonic motor, it is small and does not generate electromagnetic noise, and conventional rubber rollers can be used as they are in the conveyance section. In addition, since the above-mentioned ultrasonic motor uses a round rod-shaped piezoelectric ceramic vibrator 12 as a method of synthesizing bending vibration, it is easy to match the resonance frequencies of the two vibration modes, and the temperature of the resonance frequency The deviation due to the change is the same for both.

Furthermore, since a node common to the two vibration modes is formed, the vibrator 12 can be stably supported.

[0011]

[Problems to be Solved by the Invention] However, in the ultrasonic transfer actuator and transfer device configured as described above, the vibrator 12 using the piezoelectric ceramic round bar 2 is
It is necessary to polarize the inside of the vibrator 12 in multiple ways so that it can be excited in two vibration modes. Therefore, even if the shape of the vibrator 12 allows the resonant frequencies of the two vibration modes to match, a deviation may occur during the polarization stage and the resonant frequencies may not be able to match.

When the vibrator 12 is excited in two vibration modes, a pair of electrodes with the same polarity is provided in two orthogonal directions and switched with a phase difference of 90° to generate bending vibration in the two directions. As a result, the drive circuit becomes complicated. Moreover, as described above, if the resonance frequencies cannot be matched, the drive circuit becomes even more complex.

Furthermore, as shown in FIGS. 6 and 7, the common node of the two vibration modes of the vibrator 12 is supported by the support ring 11, and by combining the two vibration modes, Because elliptical motion is generated at both ends, three-dimensional distortion occurs at the common node,
The support ring 11 cannot provide sufficiently stable support.

[0014] The present invention solves the problems of the conventional ultrasonic actuator and transfer device for transfer, simplifies the drive circuit without using two vibration modes, and furthermore, it is possible to simplify the drive circuit without using two vibration modes. It is an object of the present invention to provide an ultrasonic actuator for transportation and a transportation device that can be supported in a stable state.

[0015]

[Means for Solving the Problems] To this end, in the ultrasonic actuator for transportation according to the present invention, the main vibrator is formed of an elastic body, and when excited, two vibration nodes are formed and a secondary vibration is generated in the longitudinal direction. Generates bending vibration. The main vibrator is supported at the two vibration nodes, and sub-vibrators are integrally protruded from both ends of the main vibrator. The auxiliary oscillator is made of an elastic body like the main oscillator, and when excited, forms a vibration node at a connection point with the main oscillator to generate a first-order longitudinal bending vibration. Then, a piezoelectric element is attached to the main vibrator.

When the ultrasonic transfer actuator having the above configuration is applied to a transfer device, a drive roller is rotatably disposed in contact with the surface of the sub-vibrator, and the object to be transferred is transferred by the drive roller. . In this case, the center point of the drive roller is placed at a position offset from the line in which the sub-vibrator vibrates. Furthermore, an object placed on an object support such as a table can be transferred without using the drive roller. In this case, a transferred object support is fixed to the vibration node of the main vibrator, the sub-vibrator is supported by a vibrator unit support, and the vibration direction of the sub-vibrator is tilted from the vertical direction.

[0017]

According to the present invention, as described above, the main vibrator is formed of an elastic body, and upon excitation, two vibration nodes are formed to generate secondary longitudinal bending vibration. In addition, sub-oscillators are integrally molded to protrude from both ends of the main oscillator, and the sub-oscillators are made of an elastic body like the main oscillator, and during excitation, there is a vibration node at the connection point with the main oscillator. to generate first-order longitudinal flexural vibration. Then, a piezoelectric element is attached to the main vibrator.

Therefore, when an alternating current voltage is applied to the piezoelectric element while supporting the two vibration nodes of the main vibrator, the main vibrator receives a secondary longitudinal bending vibration, and the sub vibrator receives a primary vibration. A longitudinal flexural vibration is generated, and the object to be transported, which is placed in contact with the sub-vibrator, is transported. When the ultrasonic transfer actuator with the above configuration is applied to a transfer device, a drive roller is rotatably disposed in contact with the surface of the sub-vibrator, and as the sub-vibrator vibrates, the drive roller is rotated. It rotates, and the object to be transported is transported by this rotation. In this case, the center point of the drive roller is placed at a position offset from the line in which the sub-vibrator vibrates.

Furthermore, it is possible to transfer an object placed on an object support such as a table without using the drive roller. In this case, a transferred object support is fixed to the main vibrator, the sub-vibrator is supported by a vibrator unit support, and the vibration direction of the sub-vibrator is tilted from the vertical direction. Then, when the sub-vibrator is vibrated, the object placed on the object support is transferred.

[0020]

Embodiments Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In this embodiment, a transport ultrasonic actuator and a transport device for transporting sheets or cards including recycled paper will be described. FIG. 1 is a perspective view of a vibrator used in a drive section of an ultrasonic actuator for transportation according to the present invention.

In the figure, 20 is an I-shaped vibrator, 21
is a main oscillator made of an elastic body, and 22 and 23 are the main oscillators 2.
The first and second sub-vibrators 24, which are made of an elastic body and are formed protruding from both ends of the vibrator 1, are supporting and fixing holes. The main vibrator 21 and the first and second sub-vibrators 22 and 23 are integrally molded. The main vibrator 21 has a prismatic shape, whereas the first and second sub-vibrators 22 and 23 have a cylindrical shape. The reason why the main vibrator 21 has a prismatic shape is to make it easier to adhesively fix the piezoelectric element used as the driving element of the ultrasonic transport actuator. The reason for the cylindrical shape is to satisfy the driving conditions for obtaining an output as an ultrasonic actuator for transport.

FIG. 8 is an explanatory diagram of each dimension of the vibrator. (a) of the figure shows the front (X-Z plane), and (b) shows the right side (Y-Z plane). In the figure, 2
1 is a main oscillator, 22 and 23 are first and second sub-oscillators, 2
4 is a support fixing hole. Also, a1 is the diameter of the main oscillator 21, b1 is the width of the main oscillator 21 in the Y-axis direction, L1 is the length of the main oscillator 21, L2 is the length of the first sub-oscillator 22, and L3 is the length of the first sub-oscillator 21. The length of the second sub-oscillator 23, R2 is the first
R3 is the diameter of the second sub-vibrator 23, and m is the distance between the support fixing hole 24 and the end of the main vibrator 21. Then, the values a1 and b of each part of the vibrator 20
1, L1, L2, L3, R2, R3, m)
is set so that it can be excited in a vibration mode to be described later. Then, when the cross-sectional area of the main resonator 21 is S, the cross-sectional area of the first sub-oscillator 22 is S1, and the cross-sectional area of the second sub-oscillator 23 is S2, S>S1 = S2, and the The length L2 of the first sub-oscillator 22 and the length L3 of the second sub-oscillator 23 are set as L2 = L3. Furthermore, the length L1 of the main oscillator 21 and the first
, the lengths L2 and L3 of the second sub-oscillators 22 and 23 are
1/6≦L2 /L1 =L3 /L1≦1/2. This condition is set so that the first and second sub-vibrators 22 and 23 do not become a load on the vibration energy of the main vibrator 21, and in addition, the vibration displacement of the main vibrator 21 is expanded.

Note that the dimensional ratio of the length L1 of the main resonator 21, the length L2 of the first sub-oscillator 22, and the length L3 of the second sub-oscillator 23 is set to 5:1:1. Y of vibrator 21
The dimensional ratio of the axial width b1, the diameter R2 of the first sub-oscillator 22, and the diameter R3 of the second sub-oscillator 23 is 2:1:1.
If so, it is possible to excite at a resonant frequency in the range of 20 to 40 kHz, improving drive efficiency.

Furthermore, the main oscillator 21 has a square cross-sectional shape in the Y-Z plane, and the central axis in the length direction of the main oscillator 21 is set to the length of the first and second sub-oscillators 22 and 23. If the direction coincides with the central axis of the direction, manufacturing of the vibrator 20 becomes easier. The cylindrical surfaces of the first and second sub-oscillators 22 and 23 are treated in the same way as the main transducer 21, but in consideration of the drive method of the ultrasonic transfer actuator, a wear-resistant material is applied by adhesion or vapor deposition. It is recommended to provide it on the surface.

Next, an I-shaped vibrator unit consisting of the vibrator 20 having the above structure will be explained. FIG. 9 is a configuration diagram of an I-shaped vibrator unit. (a) of the figure is the front (X
-Z plane), and (b) shows the right side (YZ plane). In the figure, 30 is a vibrator unit, 21
2 is a main vibrator, 22 is a first sub-vibrator, 23 is a second sub-vibrator, 25 is a mounting bolt, 26 is a mounting pedestal, 27 is a frame, 28 is a piezoelectric element for vibration excitation, and 29 is an output pickup. It is a piezoelectric element for Also, t1 is the piezoelectric element 2
8 is an input terminal, t2 is an output terminal of the piezoelectric element 29, and t3 is a grounding terminal of the frame 27.

FIG. 10 is a block diagram of a drive control circuit for controlling the vibrator unit. In the figure, 31 is an oscillator, 32 is a power amplifier, and 33 is a controller. Terminal t1 is connected to piezoelectric element 28 in FIG. 9, and terminal t2 is connected to piezoelectric element 29 in FIG. In addition, a of the controller 33
is the terminal to which the pickup voltage from terminal t1 is input, b
is a terminal that outputs a signal that controls the output voltage of the oscillator 31, and c is a terminal that outputs a signal that controls the output frequency of the oscillator 31.

In the above embodiment, the piezoelectric elements 28 and 29 are bonded to the vibrator 20 shown in FIG. 1 to form the vibrator unit 30, but the piezoelectric element itself is shaped as shown in FIG. It may be formed into In this case, considering that the first and second sub-oscillators 22 and 23 at both ends have a cylindrical shape, the entire vibrator 20 is formed into a cylindrical shape and provided with electrodes polarized in the vibration direction. Good too.

Next, the vibration mode of the vibrator 20 in the ultrasonic transport actuator of the present invention will be explained. FIG. 11 is a diagram showing the vibration mode of the vibrator in the ultrasonic transport actuator of the present invention. In the figure, 21
', 21'' are the states of the excited main oscillator 21, 22',
22'' is the state of the excited first sub-oscillator 22, 23'
, 23'' indicate the state of the excited second sub-oscillator 23.A is a vibration node in the secondary longitudinal bending vibration that occurs in the X direction of the main oscillator 21, and B1 is a vibration node of the main oscillator 21. 21
and the first sub-oscillator 22, and the secondary longitudinal bending vibration that occurs in the X direction of the main oscillator 21 and the primary length that occurs in the X direction of the first sub-oscillator 22. Since the directional deflection vibration is continuous, it becomes a vibration node. Further, B2 is a coupling part between the main oscillator 21 and the second sub-oscillator 23, and
Since the second-order longitudinal bending vibration that occurs in the X direction of the first sub-vibrator 23 and the first-order longitudinal bending vibration that occurs in the X direction of the second sub-vibrator 23 are continuous, they become nodes of vibration.

Then, the origin O is excited and becomes O' or O''
Move to the position indicated by . Also, the solid line shows the mode form when there is no vibration, the broken line shows the mode form when there is no vibration (T: period, n=1, 2,...), and the dashed line shows (3T/4) x n
The time mode form (T: period, n=1, 2, . . . ) is shown. In the ultrasonic actuator for transportation according to the present invention, the support fixing hole 24 shown in FIG. 1 is provided at the vibration node A, and the vibrator 20 is supported and fixed through the mounting bolt 29 shown in FIG. That is, in the X-Z plane, the vibrator 2
Using vibration node A in the secondary longitudinal bending vibration in the X direction that occurs in the main vibrator 21 of 0, force is applied in the Y direction perpendicular to the vibration direction to restrain and support the vibrator 20. Therefore, without affecting the vibration mode, the oscillator 2
0 can be stably supported.

Furthermore, the main oscillator 21 and the first sub-oscillator 22
A coupling part B1 between the main oscillator 21 and the second sub-oscillator 2
The nodes of each vibration are made to coincide with the joint part B2 with 3. Therefore, the amplitude of the vibration generated by the piezoelectric element 28 in FIG.
, B2) as a fulcrum, and is transmitted to the tips of the first and second sub-oscillators 22, 23.

Here, the tip of the vibrator 20 of the ultrasonic actuator for transport according to the present invention, that is, the origin O in FIG.
, O', O''
It can be linearly controlled by the voltage applied to. This utilizes the relationship between the voltage and displacement of the piezoelectric element 28. Moreover, the above-mentioned amplitude becomes a factor that determines the transfer force and transfer speed of the ultrasonic actuator for transfer of the present invention. Therefore, the transfer force and transfer speed can be linearly controlled by the voltage applied to the piezoelectric element 28.

Next, the driving principle of the ultrasonic transport actuator of the present invention will be explained. FIG. 12 is a principle diagram of a mechanism for generating a transfer force in the ultrasonic transfer actuator of the present invention. In the figure, 21 is a main vibrator, 22 is a first sub-vibrator, 25 is a mounting bolt, 26 is a mounting pedestal, 27 is a frame, 28 is a piezoelectric element for vibration excitation, 29 is a piezoelectric element for output pickup, 35 is a rotating body to be transferred. Further, θ is the contact angle between the center point of the first sub-oscillator 22, that is, the direction (Z direction) in which vibration occurs at the origin O, and the contact point Q of the transferred rotating body 35, and uZ is the vibration displacement. When UZ is the amplitude, uZ = UZ
・Represented by sinωt. The vibration displacement uZ is indicated by a dotted line on the Z axis in the figure. ω is the resonant frequency of the vibrator 20 input from the oscillator 31 (FIG. 10), f(t) is the vibration force generated at the contact point Q, and P is the push from the first sub-vibrator 22 against the rotating body 35 to be transferred. force (=f(t)・cosθ), F is the transfer force (=μ・P), μ is the friction coefficient between the transferred rotating body 35 and the first sub-oscillator 22, OR is the transferred rotating body 35
is the center point of

As described above, in the ultrasonic transfer actuator of the present invention, the main vibrator 21 of the vibrator unit 30
Then, a longitudinal bending vibration in the X direction is generated in the first and second sub-vibrators 22 and 23, and the first sub-vibrator 22 is vibrated with a vibration displacement uZ. At this time, the rotating body 35 to be transferred
The center point OR is the direction in which the first sub-oscillator 22 vibrates,
That is, it is offset from the Z-axis and is brought into contact with the first sub-oscillator 22 at a contact angle θ with respect to the Z-axis.
A vibration force f(t
) occurs, and as a result, the center point OR of the transferred rotating body 35
A pressing force P is generated in the direction of . Here, since the coefficient of friction between the first sub-vibrator 22 and the transferred rotating body 35 is μ, the pressing force P causes the tangential direction passing through the contact point Q,
That is, a frictional force, that is, a transfer force F is generated in the transfer direction.

If the vibration displacement uZ is in the positive direction of the Z-axis, the transfer force F is generated in the direction shown in FIG. In other words, the transfer force F of the rotating body 35 to be transferred is expressed as F=μ·P. The transfer force F becomes a rotational force that rotates the transferred rotating body 35 in the direction of arrow C around the center point OR.

Next, when the vibration displacement uZ becomes in the negative direction of the Z-axis, the first sub-vibrator 22 no longer comes into contact with the rotating body 35 to be transferred, and no transfer force F is generated. Therefore, the transferred rotating body 35 does not rotate. In this case, the rotating body 3 to be transferred
The position of the center point OR of 5 is fixed. FIG. 13 is a vibration locus diagram of the contact point between the sub-oscillator and the transferred rotating body. In this case as well, the position of the center point OR of the rotating body 35 to be transferred is fixed.

In the figure, 22 is the first sub-oscillator, 35
is the rotating body to be transferred, OR is the center point of the rotating body 35 to be transferred,
θ is the contact angle, and the origin O is the vibration center of the first sub-oscillator 22. If there is no rotating body 35 to be transferred, the contact point Q will be along the vibration locus line (Q-D0 -Q-E
0 - Q) and move. However, in reality, the transferred rotating body 35 is in contact with the first sub-oscillator 22 at the contact angle θ, so the contact point Q is the vibration locus line shown by the solid line (Q-D1
-E1 -Q) and move.

Therefore, the rotating body 35 to be transferred receives the transfer force F shown in FIG.
In the section -Q, it does not come into contact with the first sub-oscillator 22, so it continues to rotate in the same direction of arrow C. and,
The rotation continues by repeating the vibration of the vibration trajectory line (Q-D1-E1-Q). 12 and 13 show that in the coordinate system (Y-Z plane, origin O) of the first sub-oscillator 22, the center point of the first sub-oscillator 22 is vibrated in the Z-axis direction, and the rotating body 35 to be transferred is is the first sub-oscillator 2 in the second quadrant.
2 is explained.

FIG. 14 is a diagram showing the relationship between the position and rotation direction of the rotating body to be transferred. The center point of the first sub-oscillator 22 is set as the origin O, and the rotating body 35 (35a to 35d) to be transferred is located in each quadrant from the first quadrant to the fourth quadrant in the coordinate system,
The first sub-oscillator 2 is brought into contact with the first sub-oscillator 22.
2 in the Z direction. In the figure, each of the rotating bodies 35a to 35d to be transferred is arranged in all quadrants for explanation purposes, but in reality, as long as it is within the driving capacity of the ultrasonic actuator for transfer, they can be arranged as shown in the figure. It is possible.

O1 to O4 are each transferred rotating body 35a to
35d center point, θ11 to θ14 are contact angles, Q11 to
Q14 is a contact point, and C1 to C4 are rotation directions. It can be seen that the rotational directions C1 to C4 of the transferred rotating bodies 35a to 35d are determined for each quadrant of the coordinate system in which the vibration direction of the first sub-oscillator 22 is the Z direction. By the way, in the above embodiment, the transferred rotating bodies 35 (35a to 35d
) The case where the position of the center point OR (O1 to O4) is fixed is explained. However, two conditions are met: the vibration region used by the transfer ultrasonic actuator is an ultrasonic vibration region, and the transfer force F acting on the transferred rotating body 35 is smaller than the vibration force possessed by the vibrator 20. If satisfied, the center point OR (O1
~O4) It is possible to jump and rotate the transferred rotating body 35 using the same driving principle without fixing the position.

Therefore, even if it is not the rotating body 35 to be transferred, when a flat object to be transferred such as a sheet or a card is brought into contact with the first sub-vibrator 22 at a contact angle θ from the vibration direction, the contact point A transfer force F can be generated. FIG. 15 is a diagram showing the relationship between the position of a flat plate-shaped object and the direction of transport. In the figure, 22 is a first sub-oscillator, 36a to 36d are planar objects to be transferred, θ21 to θ24 are contact angles, Q21 to Q
24 is a contact point. When the objects to be transferred 36a to 36d are brought into contact with the first sub-vibrator 22 in the first to fourth quadrants, the transfer direction of the objects to be transferred 36a to 36d is G1 to G.
It becomes 4.

Next, a transfer device using the ultrasonic transfer actuator configured as described above will be explained. In this case, the contact angle θ between the vibration direction of the vibrator 20 and the contact point Q of the transferred object is 30°. FIG. 16 is a perspective view of the transfer device of the present invention, and FIG. 17 is a side view of the transfer device of the present invention.

In the figure, reference numerals 30a and 30b are transducer units constituting the driving section of the ultrasonic actuator for transport, and the transducer units 30a and 30b are provided with drive rollers 3 and 30b.
8 are brought into contact with each other, and the rotational force of this drive roller 38 is used to transfer an object 40, such as a sheet or a card, which is sandwiched between the auxiliary roller 39 and the drive roller 38.

Further, 21a and 21b are main oscillators, 22a
, 22b is a first sub-oscillator, 23a is a second sub-oscillator,
25a, 25b are mounting bolts, 26a, 26b are mounting pedestals, 27 is a frame, 28a, 28b are piezoelectric elements for vibration excitation, 29a, 29b are piezoelectric elements for output pickup, 41 is a shaft, 42 is a pressing spring, θ1 ,θ2
is the contact angle.

As described above, the embodiment shown in FIGS. 16 and 17 has a structure in which the vibrator units 30a and 30b are attached to both sides of the frame 27 shown in FIG. 12. Then, Z by the vibrator unit 30a.
1. Vibration occurs on the first axis (Fig. 17), and the first sub-oscillator 2
The drive roller 38, which is in contact with the roller 2a at a contact angle θ1, rotates in the direction of the arrow Ha. As a result, the auxiliary roller 39
The transferred object 40 sandwiched between the drive roller 38 and the drive roller 38 is transferred in the direction of arrow J.

[0045] Also, Z2
Vibration occurs on the shaft and the drive roller 38, which is in contact with the first sub-vibrator 22b at a contact angle θ2, moves as shown by the arrow Hb.
Rotate in the direction. As a result, the object 40 sandwiched between the auxiliary roller 39 and the drive roller 38 is transferred in the direction of arrow K. In the transfer device having the above configuration, the vibrator unit 30
Since oscillators a and 30b have the same shape and size with exactly the same drive characteristics, only one drive circuit in FIG. The vibrator units 30a and 30b to be used are selected. Therefore, the drive circuit can be simplified. Note that the cylindrical surfaces of the vibrator units 30a and 30b are coated with a wear-resistant material by adhesion or surface vapor deposition in order to stabilize drive performance.

Next, a transfer device in which the transfer surface of the drive roller 38 is prevented from coming into contact with the first and second sub-vibrators 22a, 22b, and 23a will be described. FIG. 18 is a diagram showing a second embodiment of the transfer device of the present invention. In the figure,
44 is a drive roller with a step in the X0 axis direction;
Consisting of a large diameter part 44a and a small diameter part 44b, the large diameter part 44a
becomes a transfer surface for the transferred object 40, and the small diameter portion 44b becomes a contact surface with the first sub-vibrator 22a.

FIG. 19 is a diagram showing a third embodiment of the transfer device of the present invention. In the figure, reference numeral 45 denotes an annular drive roller, the outer circumferential surface of the drive roller 45 serves as a transfer surface for the object 40, and the inner circumferential surface serves as a contact surface with the first sub-vibrator 22a, 22b. When transferring the object 40 in the direction of arrow J, the transducer unit 30a is driven, and when transferring the object 40 in the direction of arrow K, the transducer unit 30b is driven.

Next, a description will be given of a transfer device for transferring objects such as sheets of paper and cards placed on a table. FIG. 20 is a diagram showing a table-type transfer device configured using two vibrator units. In the figure, 21
a, 21b are main vibrators, 22a, 22b are first sub vibrators, 25a, 25b are mounting bolts, 26a, 26b are mounting pedestals, 27 is a frame, 28a, 28b are piezoelectric elements for vibration excitation, 29a, 29b is a piezoelectric element for output pickup, 40 is an object to be transferred such as a sheet or card, and 47 is the first sub-vibrator 22a of the vibrator units 30a, 30b.
.

In the transfer device configured as described above, the object 40 placed on the table 48 is transferred. Then, the direction of vibration generated in the vibrator unit 30a is set to Z1.
In the axial direction, the Z1 axis and the vertical line have a contact angle θ1
The first sub-oscillator 22a is in contact with the rail 47 so as to form the following. Further, assuming that the direction of vibration generated in the vibrator unit 30b is the Z2 direction, the first sub-vibrator 22b is in contact with the rail 47 such that the Z2 axis and the vertical line form a contact angle θ2. The rail 47 is fixed at both ends, and the object 4 placed on the table 48 is
0 is transferred in the direction of arrow J when the transducer unit 30a is driven, and in the direction of arrow K when the transducer unit 30b is driven. Note that in order to improve drive performance, the first sub-vibrator 22a of the vibrator units 30a and 30b is
, 22b, that is, the contact surface with the rail 47, can be coated with a wear-resistant material by adhesion or surface vapor deposition.

Further, in the above embodiment, the rail 47 is fixed and the object 40 on the table 48 is transferred, but conversely, the table 48 is fixed and the rail 4
An object to be transferred 40 may be placed on top of the container 7. It should be noted that the present invention is not limited to the above embodiments, and various modifications can be made based on the spirit of the present invention, and these are not excluded from the scope of the present invention.

For example, the ultrasonic transport actuator of the present invention can use the transducer unit 30 (FIG. 9) as a general-purpose actuator in its drive section. That is, a rotary motor can be constructed using the rotational force output by the drive rollers 38, 44, and 45 in FIGS. 16 to 19, and a linear motor can be constructed as is in the case of FIG. 20. can.

According to the drive principle shown in FIG. 12, the vibrator unit 30 has a braking function and a holding function using frictional force when vibration is stopped, and highly accurate feeding and positioning are possible. Therefore, for rotary motors,
It can be used for the rotary table of measurement equipment, the fine focus adjustment mechanism of lenses, the joint drive mechanism of assembly robots, and in the case of linear motors, it can be used for the positioning mechanism of magnetic disk reading heads, the carriage drive mechanism of printer heads, and the X- Y
It can be used for a biaxial drive mechanism of a plotter or a pen vertical drive mechanism.

[0053]

As described above in detail, according to the present invention, the main vibrator forms two vibration nodes to generate secondary longitudinal bending vibration, and the sub vibrator generates the main vibrating vibration. A vibration node is formed at the connection portion with the vibrator to generate first-order longitudinal bending vibration, and the two vibration nodes are supported. The above two vibration nodes can be supported and fixed in a direction perpendicular to the vibration direction, and can be stably supported without affecting the vibration mode.

[0054] Furthermore, since only the first-order longitudinal bending vibration occurs in the sub-oscillator, it is easy to design and manufacture the shape of the sub-oscillator, and the drive circuit can also be simplified. can. Furthermore, since a piezoelectric element is used as the drive source, the drive unit can be made lighter and smaller. Since the drive unit is made into a unit by the main vibrator, sub-vibrator, and piezoelectric element, it is not only easy to design the transfer device, but also suitable for transferring objects such as sheets and cards. It becomes possible to apply it as a general-purpose motor.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a vibrator used in a drive section of an ultrasonic actuator for transportation according to the present invention.

FIG. 2 is a perspective view of a piezoelectric ceramic vibrator.

FIG. 3 is a diagram showing the relationship between applied voltage and generated distortion.

FIG. 4 is a diagram showing a state of excitation in a vibration mode.

FIG. 5 is a drive circuit diagram for continuous excitation.

FIG. 6 is a perspective view of a single point circumscribed ultrasonic motor.

FIG. 7 is a perspective view of a single-point internal type ultrasonic motor.

FIG. 8 is an explanatory diagram of each dimension of the vibrator.

FIG. 9 is a configuration diagram of an I-shaped vibrator unit.

FIG. 10 is a block diagram of a drive control circuit for controlling the vibrator unit.

FIG. 11 is a diagram showing vibration modes of a vibrator in the ultrasonic actuator for transportation according to the present invention.

FIG. 12 is a principle diagram of a mechanism for generating a transfer force in the ultrasonic transfer actuator of the present invention.

FIG. 13 is a vibration locus diagram of the contact point between the sub-oscillator and the rotating body to be transferred.

FIG. 14 is a diagram showing the relationship between the position and rotation direction of the rotating body to be transferred.

FIG. 15 is a diagram showing the relationship between the position of a flat object to be transported and the transport direction.

FIG. 16 is a perspective view of the transfer device of the present invention.

FIG. 17 is a side view of the transfer device of the present invention.

FIG. 18 is a diagram showing a second embodiment of the transfer device of the present invention.

FIG. 19 is a diagram showing a third embodiment of the transfer device of the present invention.

FIG. 20 is a diagram showing a table-type transfer device configured using two vibrator units.

[Explanation of symbols]

20 Vibrator 21 Main oscillator 22 First sub-oscillator 23 Second sub-oscillator 24 Support fixing hole 28, 29 Piezoelectric element A Node of vibration

Claims (3)

[Claims] Claim 1: (a) a main vibrator made of an elastic body, which forms two vibration nodes during excitation to generate secondary longitudinal bending vibration; and (b) a main vibrator made of an elastic body, two auxiliary oscillators integrally formed at both ends of the oscillator to form a vibration node at a joint with the main oscillator to generate a first-order longitudinal bending vibration during excitation; An ultrasonic actuator for transport comprising: (c) supporting means for supporting two vibration nodes of the main vibrator; and (d) a piezoelectric element provided on the main vibrator. 2. (a) a main vibrator made of an elastic body, which forms two vibration nodes during excitation to generate secondary longitudinal bending vibration; and (b) a main vibrator made of an elastic body, two auxiliary oscillators integrally formed at both ends of the oscillator to form a vibration node at a joint with the main oscillator to generate a first-order longitudinal bending vibration during excitation; (c) supporting means for supporting two vibration nodes of the main vibrator; (d) a piezoelectric element provided on the main vibrator; and (e) rotatable in contact with the surface of the sub-vibrator. (f) a center point of the drive roller is placed at a position offset from a line in the direction in which the sub-vibrator vibrates. 3. (a) a main oscillator made of an elastic body, which forms two vibration nodes during excitation to generate secondary longitudinal bending vibration; and (b) a main oscillator made of an elastic body, two auxiliary oscillators integrally formed at both ends of the oscillator to form a vibration node at a joint with the main oscillator to generate a first-order longitudinal bending vibration during excitation; (c) a piezoelectric element provided on the main vibrator; (d) an object support that is fixed to two vibration nodes of the main vibrator and on which an object is placed; (e ) a vibrator unit support for supporting the sub-vibrator, and (f) a transfer device characterized in that the vibration direction of the sub-vibrator is inclined from the vertical direction.