JPH04355678A - Ultrasonic wave actuator for conveyer and converter thereof - Google Patents

Abstract

PURPOSE:To obtain a stable vibration mode without necessity of bringing resonance frequencies of different vibration modes into coincidence or approaching them by supporting a multiple mode vibrator in a stable state. CONSTITUTION:A first arm 1, a second arm 2 molded integrally with the arm 1, and a subvibrator 3 molded integrally with the end of the arm 2 to protrude, are provided, and piezoelectric devices are provided at the arm 1 and the arm 2 parallel to a plane including the arm 2. When a voltage is applied to the device to excite the arm l, a primary longitudinal twisting vibration is generated. When the arm 2 is excited, a secondary longitudinal deflecting vibration is generated. When the subvibrator 3 is excited, a node of the vibration is formed at a coupling part with the arm 2 to generate a primary longitudinal deflecting vibration. A contact point of the subvibrator 3 with a material to be transferred, is placed at a position deviated from a line of the direction in which the subvibrator 3 is vibrated, a voltage is applied to the element to excite the subvibrator 3, and a material to be transferred, in contact with the subvibrator 3 is transferred by the vibration.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention is applicable to sheets of paper 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

2. Description of the Related Art Conventionally, an ultrasonic actuator for transportation is configured to excite a traveling wave in an elastic body and move an object placed on the surface of the elastic body by frictional force. In this case, in order to obtain a traveling wave, special consideration must be given to preventing the generation of reflected waves and energy feedback. In contrast, there has been provided an ultrasonic actuator for transportation that actively utilizes the unique resonance state of an elastic body and uses standing waves. In this case, the energy conversion efficiency is high and the vibration energy is essentially large compared to an ultrasonic actuator for transportation that uses traveling waves.

FIG. 2 is a diagram showing an ultrasonic motor for paper feeding using a multi-mode vibrator that utilizes longitudinal vibration and bending vibration. In the figure, (a) shows the plane of the multimode vibrator, (b) shows the front, and (c) shows the side. This ultrasonic motor for paper feeding uses longitudinal vibration in the longitudinal direction and bending vibration in the width direction of a rectangular plate, and the resonance frequency of the longitudinal vibration and the resonance frequency of the bending vibration in the width direction are close to each other. It is set as follows.

In the figure, 50 is a multimode oscillator;
1 is an elastic flat plate made of fiber-reinforced plastic, metal plate, fiber-reinforced metal, etc.; 52 is a PZT-based piezoelectric ceramic plate; 53 is an electrode formed on both the front and back sides of the piezoelectric ceramic plate 52; and 54 and 55 are voltage terminals. be. The piezoelectric ceramic plate 52 and the elastic flat plate 51 are firmly bonded with solder or epoxy adhesive. Further, L, W, and T are the length, width, and thickness of the multimode vibrator 50, respectively,
T1 is the thickness of the elastic flat plate 51, and T2 is the thickness of the piezoelectric ceramic plate 52.

Next, the principle of operation of the multimode vibrator 50 will be explained. When the piezoelectric ceramic plate 52 receives an AC voltage from the voltage terminals 54 and 55 and is excited and extends in the longitudinal direction, it contracts in the width direction by an amount determined by Poisson's ratio. Conversely, when the piezoelectric ceramic plate 52 contracts in the longitudinal direction, it expands in the width direction. And the multi-mode oscillator 50
Since the resonant frequency fL1,l of the longitudinal vibration in the longitudinal direction and the resonant frequency fB1,w of the bending vibration in the width direction are sufficiently close to each other, when the longitudinal vibration shown by the arrow in (a) is generated, the piezoelectric ceramic The width of the plate 52 changes, resulting in (c
) is forcibly generated as shown by the broken line. At this time, while the piezoelectric ceramic plate 52 expands and contracts in the longitudinal direction, since the elastic flat plate 51 has no piezoelectric effect, bending vibration in the longitudinal direction also occurs.

FIG. 3 is a diagram showing vibration modes of a multimode oscillator. Figure (a) shows the displacement of longitudinal vibration in the longitudinal direction,
(b) shows the displacement of bending vibration in the longitudinal direction, (c) shows the bending vibration mode of the elastic flat plate, and (d) shows the displacement of bending vibration in the width direction. In the figure, ξL1,l represents a displacement of longitudinal vibration in the length direction, ξB1,l represents a displacement of bending vibration in the length direction, and ξB1,w represents a displacement of bending vibration in the width direction. Here, L1 and B1 are 1 of longitudinal vibration and bending vibration, respectively.
This means the next natural resonance mode. (c) (+), (
The symbol -) indicates the direction of displacement of the elastic flat plate 51 in the bending vibration mode.

FIG. 4 is an explanatory diagram of an ultrasonic motor for paper feeding. In the figure, (a) shows the plane of the ultrasonic motor for paper feeding, and (b)
) shows the front view, and (c) shows the relationship between longitudinal vibration and bending vibration displacement. As shown in the figure, the bending vibration displacement uB and the longitudinal vibration displacement uL on the pressure contact surface are orthogonal and synchronized. When paper 57 is inserted between roller 56 and multimode vibrator 50, paper 57 moves in the direction of the arrow.

[0008]

[Problems to be Solved by the Invention] However, in the above-described conventional ultrasonic transport actuator and transport device, longitudinal vibration in the longitudinal direction and bending vibration in the width direction are used as the multimode vibrator 50, and two Although the two vibration resonance frequencies fL1,l and fB1,w are set close to each other, they do not have a common vibration node. Therefore, it is necessary to support the multimode vibrator 50 with a material that absorbs vibrations, such as a rubber plate, and a stable state cannot be obtained.

[0009] Furthermore, since the vibration modes are different for longitudinal vibration and bending vibration, the respective resonance frequencies fL1, l, fB1,
It is difficult to make w close to each other. Furthermore, since two vibrations that do not have a common vibration node are generated within the same elastic flat plate 51, each vibration becomes unstable. The present invention solves the problems of conventional ultrasonic actuators and transfer devices, can stably support a multi-mode vibrator, and requires that the resonance frequencies of different vibration modes match or be close to each other. It is an object of the present invention to provide an ultrasonic actuator for transportation and a transportation device that can obtain a stable vibration mode without causing vibration.

0010

[Means for Solving the Problems] To this end, in the ultrasonic actuator for transportation of the present invention, a first arm is formed of an elastic body, and a second arm is formed integrally with the first arm and extends at right angles. and a sub-vibrator integrally formed and projected from the end of the second arm.

During excitation, the first arm generates a first-order longitudinal torsional vibration, the second arm generates a second-order longitudinal bending vibration, and the sub-oscillator interacts with the second arm. Vibration nodes are formed at the joints of the two to generate first-order longitudinal bending vibrations. An end of the first arm is supported by a support means, and a piezoelectric element is provided on a surface of the second arm parallel to a plane including the first arm and the second arm.

The length of the second arm is greater than the length of the first arm, and the cross-sectional area of the second arm is larger than the cross-sectional area of the sub-oscillator. When the ultrasonic transfer actuator having the above configuration is applied to a transfer device, the point of contact between the sub-vibrator and the object to be transferred is placed at a position offset from the line in which the sub-vibrator vibrates.

[0013] Further, a drive roller is rotatably disposed in contact with the surface of the sub-vibrator, and the center point of the drive roller is placed at a position offset from the line in which the sub-vibrator vibrates. . Further, a transferred object support for placing an object to be transferred is fixed to the support means of the first arm, a sub-vibrator is supported by the support, and a vibration direction of the sub-vibrator is tilted from the vertical direction. .

[0014]

[Operation] According to the present invention, as described above, the first arm is formed of an elastic body, the second arm is formed integrally with the first arm and extends at right angles, and the end of the second arm is formed of an elastic body. It has a sub-oscillator that is integrally molded to protrude,
A second arm parallel to a plane including the first arm and the second arm.
A piezoelectric element is provided on the surface of the arm.

Therefore, when a voltage is applied to the piezoelectric element to excite the first arm, first-order longitudinal torsional vibration occurs. Furthermore, when the second arm is excited, a second-order longitudinal bending vibration is generated, and when the sub-oscillator is excited, a vibration node is formed at the joint with the second arm, and a first-order longitudinal bending vibration is generated. Generates bending vibration. That is, since no bending vibration occurs in the first arm, the support means that supports the end of the first arm does not affect the vibration generated in the second arm.

Furthermore, since the length of the second arm is greater than the length of the first arm, and the cross-sectional area of the second arm is larger than the cross-sectional area of the sub-oscillator, the The vibration is transmitted to the sub-oscillator and its amplitude is expanded. When the ultrasonic transfer actuator having the above configuration is applied to a transfer device, the point of contact between the sub-vibrator and the object to be transferred is placed at a position offset from the line in which the sub-vibrator vibrates. In this way, when a voltage is applied to the piezoelectric element to excite the sub-vibrator, the object to be transferred that comes into contact with the sub-vibrator is transferred by the vibration.

[0017] Further, a drive roller is provided to be rotatable in contact with the surface of the sub-vibrator, and the center point of the drive roller is
When the sub-vibrator is placed at a position offset from the line in the direction of vibration, a drive roller in contact with the sub-vibrator rotates as the sub-vibrator is excited. Then, a transferred object support on which the transferred object is placed is fixed to the support means of the first arm, the sub-vibrator is supported by the support, and the vibration direction of the sub-vibrator is tilted from the vertical direction. Then, the object to be transferred on the object support is transferred as the sub-oscillator is excited.

[0018]

Embodiments Hereinafter, embodiments of the present invention will be described in detail with reference to the 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. In the figure, 30 is a vibrator made of an L-shaped elastic body;
1 is a first arm; 2 is a second arm extending perpendicularly to the first arm 1;
3 is an auxiliary vibrator, 4 is a fixed flange connected to the second arm 2, and 5 is a fixed hole. the first arm 1;
The second arm 2 and the sub-vibrator 3 are integrally formed of an elastic body. Further, while both arms 1 and 2 have a prismatic shape, the sub-oscillator 3 has a cylindrical shape. The reason why both arms 1 and 2 have a prismatic shape is to make it easier to bond and fix a piezoelectric element used as a driving element to the vibrator 30, and the reason why the sub-vibrator 3 has a cylindrical shape This is to obtain an output as an ultrasonic actuator for transportation.

FIG. 5 is an explanatory diagram of each dimension of the vibrator. (a) of the figure is a plan view (XY plan view), and (b) shows a front view (YZ plan view). In the figure, 1 is a first arm, 2 is a second arm, 3 is a sub-vibrator, 4 is a fixed flange, 5 is a fixing hole, and 30 is a vibrator. Also, a
1 is the width of the first arm 1 in the X-axis direction, a2 is the width of the second arm 2 in the Y-axis direction, b1 is the width of the first arm 1 in the Z-axis direction, and b2 is the width of the second arm 2 in the Z-axis direction. width, L1 is the length of the first arm 1, L2 is the length of the second arm 2, L
3 is the length of the sub-oscillator 3, and R is the diameter of the sub-oscillator 3. The values of each part of the vibrator 30 (a1, a2, b1, b
2, L1, L2, L3, R) are set so that they can be excited in a vibration mode described later. Then, the length L1 of the first arm 1 and the length L2 of the second arm 2
is L2 ≧L1, the cross-sectional area of the second arm 2 is S2, and the Y of the sub-oscillator 3 is
- When the cross-sectional area of the -Z plane is S, it is assumed that S2 >S. This is a condition set by the fact that the piezoelectric element is bonded to the second arm 2 of the vibrator 30, and the area of the bonded part is related to the output of the piezoelectric element. This condition is set so that the sub-vibrator 3 does not become a load with respect to the vibration energy of the second arm 2, and furthermore, the vibration displacement of the second arm 2 is expanded.

Note that the dimension ratio of the length L1 of the first arm 1 and the length L2 of the second arm 2 is 1:2, and the width a1 of the first arm 1 in the X-axis direction and the Y-axis of the second arm 2 are The dimension ratio of the width a2 in the direction is 1:3, the dimension ratio of the width b1 of the first arm 1 in the Z-axis direction and the width b2 of the second arm 2 in the Z-axis direction is 1:1, and If the shape of the cross section in the Y-Z plane of No. 2 is square, it can be excited at a resonant frequency in the range of 20 to 40 kHz, and the driving efficiency of the vibrator 30 is improved.

The cylindrical surface of the sub-oscillator 3 is subjected to the same treatment as the first arm 1 and the second arm 2, but in consideration of the drive method of the ultrasonic transfer actuator, a wear-resistant material is applied to the surface by adhesion or vapor deposition. It is good to have one. Next, an L-shaped vibrator unit including the vibrator 30 having the above configuration will be explained.

FIG. 6 is a configuration diagram of an L-shaped vibrator unit. (a) of the figure is a front view (YZ plan view), (b) is a bottom view (XY plan view), and (c) is a right side view (ZX plan view). In the figure, 31 is a transducer unit, 1
is the first arm, 2 is the second arm, 3 is the sub-oscillator, 4 is the fixed flange, 5 is the fixed hole, 6 is the mounting bolt, 7 is the mounting pedestal, 8 is the mounting flange, 9 is for output pickup and vibration excitation 10 is a piezoelectric element for vibration excitation.

The piezoelectric element 9 is used as a sensor element for detecting vibration to follow and form a resonance point of the vibrator 30, and also as a driving element for exciting the vibrator 30 to a predetermined vibration mode. It is designed so that it can be electrically switched depending on when it is used as an element. Further, the piezoelectric element 10 is used as a driving element for constantly exciting the vibrator 30 in a predetermined vibration mode.

FIG. 7 is a block diagram of a drive control circuit for controlling the vibrator unit. In the figure, 11 is an oscillator, 12 is a power amplifier, 13 is a signal switcher, and 14 is a controller. The terminal t1 is connected to the piezoelectric element 9 in FIG.
2 is connected to the piezoelectric element 10. Also, a is the terminal t1
b is a terminal for inputting the pickup voltage from the controller 14, c is a terminal for outputting a signal to control the switching device 13 from the controller 14,
d is a terminal from which the controller 14 outputs a signal for controlling the output voltage of the oscillator 11, and d is a terminal from which the controller 14 outputs a signal for controlling the output frequency of the oscillator 11.

In the above embodiment, the piezoelectric elements 9 and 10 are bonded to the vibrator 30 shown in FIG.
However, the piezoelectric element alone may be formed into an L-shape as shown in FIG. 1, and polarized electrodes may be applied thereto. Next, the vibration mode of the vibrator 30 in the ultrasonic transport actuator of the present invention will be explained.

FIG. 8 is a diagram showing the vibration mode of the vibrator in the ultrasonic transport actuator of the present invention. In the figure, 1 is the first arm, 2 is the second arm, 3 is the sub-oscillator, 2', 2'' is the excited state of the second arm 2, 3',
3'' indicates the excited state of the sub-oscillator 3.

A is a fixed end of the vibrator 30, which is a connecting portion between the fixed flange 4 and the first arm 1 in FIG. b is the intersection of the first arm 1 and the second arm 2, c is the vibration node of the longitudinal bending vibration that occurs in the X direction of the second arm 2, and d is the joint between the second arm 2 and the sub-oscillator 3. be. In the case of this embodiment, since the secondary longitudinal flexural vibration mode of the second arm 2 and the primary longitudinal flexural vibration mode of the sub-oscillator 3 are continuous, a vibration node is formed at the coupling portion d. be done.

[0028] The solid line represents the mode form when there is no vibration, and the broken line represents (
The mode form at (T/4)×n time (T: period, n=1, 2,...) is shown by the dashed dotted line at (3T/4)×n time (T: period, n
=1, 2,...) mode form is shown. Further, the origin O of the coordinates is excited and moves to the position indicated by the origin O' or the origin O''.In this way, the first arm 1 moves once in the Y direction.
The next longitudinal torsional vibration occurs, and a vibration node c is generated in the second arm 2 and the sub-oscillator 3 in the longitudinal direction of the second arm 2 and the sub-oscillator 3. A second-order longitudinal bending vibration mode is generated that forms a vibration node at the joint d. Therefore, the fixed end a does not affect the amplitude of the tip of the vibrator 30, that is, the origin O. In addition, the second arm 2 and the sub-oscillator 3
Since the coupling part d and the vibration node are made to coincide with each other, the amplitude of the vibration excited by the piezoelectric elements 9 and 10 adhesively fixed to the second arm 2 is expanded using the coupling part d as the fulcrum of the lever principle. be done.

In the vibrator 30 having the above structure, different types of vibration modes are not allowed to coexist within the same elastic body, so a stable vibration mode can be obtained. The resonance frequency f1 of the first arm 1 that excites the primary longitudinal torsional vibration, and the resonance frequency f2 of the second arm 2 and the sub-oscillator 3 that excites the secondary longitudinal bending vibration. Since the shape of the vibrator 30 is designed so that the values are the same or sufficiently close to each other, there is no need to match the resonance frequencies of different vibration modes that interfere with each other or to make them sufficiently close to each other.

Here, the tip of the vibrator 30 of the ultrasonic transfer actuator of the present invention, that is, the origin O in FIG.
The amplitude of the vibration occurring at O', O'' is determined by the piezoelectric elements 9, 1
It can be linearly controlled by the voltage applied to 0. This utilizes the relationship between voltage and displacement in the piezoelectric elements 9 and 10. 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. That is, the transfer force and transfer speed are determined by the piezoelectric elements 9,
It can be linearly controlled by the voltage applied to 10.

Next, the driving principle of the ultrasonic actuator for transport according to the present invention will be explained. FIG. 9 is a diagram showing the principle of a mechanism for generating a transfer force in the ultrasonic transfer actuator of the present invention. In the figure, 1 is the first arm;
2 is a second arm, 3 is a sub-vibrator, 6 is a mounting bolt, 7 is a mounting pedestal, 8 is a mounting flange, 9 is a piezoelectric element for output pickup and vibration excitation, and 16 is a rotating body to be transferred. Further, θ is the contact angle between the center point of the sub-oscillator 3, that is, the direction in which vibration occurs at the origin O (Z direction) and the contact point Q of the transferred rotating body 16, uZ is the vibration displacement, and UZ is the amplitude. , uZ = UZ ・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 30 input from the oscillator 11 (FIG. 7), f(t) is the vibration force generated at the contact point Q, and P is the pressing force from the sub-vibrator 3 to the transferred rotating body 16. , P=f(t)・cosθ. In addition, F is the transfer force, μ is the transferred rotating body 16
The friction coefficient, OR, between the rotating body 1 and the sub-oscillator 3 is
It is the center point of 6.

As described above, in the ultrasonic transfer actuator of the present invention, the first arm 1 of the transducer unit 31
, the second arm 2 and the sub-oscillator 3 are vibrated, and the vibration displacement u
The sub-oscillator 3 is made to vibrate at Z. At this time, the center point OR of the transferred rotating body 16 is shifted from the direction in which the sub-oscillator 3 vibrates, that is, from the Z-axis, and is brought into contact with the sub-oscillator 3 at a contact angle θ with respect to the Z-axis. A vibration force f(t) is generated at the contact point Q on the cylindrical surface of the sub-vibrator 3, and as a result, a pressing force P is generated in the direction of the center point OR of the transferred rotating body 16.

Here, the sub vibrator 3 and the rotating body 1 to be transferred are
Since the coefficient of friction between the contact points Q and 6 is μ, the pressing force P generates a frictional force, that is, a transfer force F in the tangential direction passing through the contact point Q, that is, 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 16 to be transferred is F
=μ・P. The transfer force F becomes a rotational force that rotates the transferred rotating body 16 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 sub-vibrator 3 no longer comes into contact with the rotating body 16 to be transferred, and no transfer force F is generated. Therefore, the transferred rotating body 16 does not rotate. In this case, the position of the center point OR of the rotating body 16 to be transferred is fixed. FIG. 10 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 16 to be transferred is fixed.

In the figure, 3 is the sub-oscillator, 16 is the rotating body to be transferred, OR is the center point of the rotating body 16 to be transferred, θ is the contact angle, and the origin O is the center of vibration of the sub-oscillator 3. If there is no rotating body 16 to be transferred, the contact point Q moves while drawing a vibration locus line (Q-D0 -Q-E0 -Q) shown by a broken line. However, in reality, the transferred rotating body 16 is in contact with the sub-oscillator 3 at the contact angle θ, so the contact point Q moves along the vibration locus line (Q-D1-E1-Q) shown by the solid line. Become.

Therefore, the transferred rotating body 16 has a transfer force F shown in FIG.
It rotates in the direction of arrow C, and does not come into contact with the sub-oscillator 3 in the section D1-E1-Q, so it rotates in the direction of arrow C.
Continue rotating in the direction. Then, the vibration locus line (Q-D
1 -E1 -Q) The rotation continues by repeating the vibrations.

By the way, FIGS. 9 and 10 show the sub-oscillator 3
The center point of the sub-oscillator 3 is vibrated in the Z-axis direction in the coordinate system (Y-Z plane, origin O), and the rotating body 16 to be transferred is moved to the second
Although a case has been described in which the rotating body 16 to be transferred is brought into contact with the sub-oscillator 3 within a quadrant, it is also possible to place the rotating body 16 to be transferred in another quadrant. FIG. 11 is a diagram showing the relationship between the position and rotation direction of the rotating body to be transferred.

The center point of the sub-oscillator 3 is set as the origin O, and the rotating body 16 (16a to 16d) to be transferred is positioned in each quadrant from the first to the fourth quadrant in the coordinate system, and the sub-oscillator 3 to vibrate the sub-oscillator 3 in the Z direction. In the figure, for the sake of explanation, each of the rotating bodies 16a to 1 to be transferred is shown in all quadrants.
6d, but in reality, the arrangement can be made as shown in the figure as long as it is within the driving capacity of the ultrasonic actuator for transport.

[0039] O1 to O4 are each transferred rotating body 16a to
16d center point, θ11~θ14 are contact angles, Q11~
Q14 is a contact point, and C1 to C4 are rotation directions. For each quadrant of the coordinate system in which the vibration direction of the sub-oscillator 3 is the Z direction, the rotational direction C1 of each transferred rotating body 16a to 16d is determined.
It can be seen that C4 is determined. By the way, in the above-mentioned embodiment, the case where the position of the center point OR (O1 to O4) of the rotating bodies 16 (16a to 16d) to be transferred 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 16 is smaller than the vibration force possessed by the vibrator 30. If the condition is satisfied, the transferred rotating body 16 can be jumped and rotated using the same driving principle without fixing the position of the center point.

Therefore, even if it is not the rotating body 16 to be transferred, when a flat object such as a sheet or a card is brought into contact with the sub-vibrator 3 at a contact angle θ from the vibration direction, a transfer force is generated at the contact point. F can be generated. FIG. 12 is a diagram showing the relationship between the position of a flat plate-shaped object and the direction of transport. In the figure,
3 is a sub-oscillator, 17a to 17d are planar objects to be transported, θ
21 to θ24 are contact angles, and Q21 to Q24 are contact points. When the transferred objects 17a to 17d are brought into contact with the sub-oscillator 3 in the first to fourth quadrants, the transferred objects 17a to 1
The transfer direction of 7d is G1 to G4.

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 30 and the contact point Q of the transferred object is 30°. FIG. 13 is a diagram showing a transfer device that allows the transducer of the ultrasonic actuator for transfer of the present invention to directly contact the object to be transferred.

In the figure, 1 is a first arm, 2 is a second arm, 3 is a sub-oscillator, 6 is a mounting bolt, 7 is a mounting pedestal,
8 is a mounting flange, 9 is a piezoelectric element for output pickup and vibration excitation, 18 is an auxiliary roller, 19 is a bearing, 2
0 is a transport rail, and 21 is an object to be transported such as a sheet of paper or a card. Basically, it is composed of a vibrator unit 31 and an auxiliary roller 18, and the object 21 to be transferred is sandwiched between the auxiliary vibrator 3 and the auxiliary roller 18, and is transferred in the direction of arrow J. The vibrator 30 is vibrated in the Z-axis direction by the piezoelectric elements 9 and 10 (see FIG. 6), and the auxiliary roller 18 is
It contacts the Z-axis direction at a contact angle θ and rotates in the direction of arrow M.

Next, a drive roller is installed between the auxiliary vibrator 3 and the auxiliary roller 18 as the rotating body 16 to be transferred, and a transfer device is constructed in which the object 21 to be transferred is sandwiched between the drive roller and the auxiliary roller 18 and transferred. I will explain about it. FIG. 14 is a diagram showing a first embodiment of a transfer device using a rotating body to be transferred, and FIG. 15 is a diagram showing a second embodiment of a transfer device using a rotating body to be transferred.

In the figure, 1 is a first arm, 2 is a second arm, 3 is a sub-oscillator, 6 is a mounting bolt, 7 is a mounting pedestal,
8 is a mounting flange, 9 is a piezoelectric element for output pickup and vibration excitation, 18 is an auxiliary roller, 19 is a bearing of the auxiliary roller 18, 20 is a transfer rail, 21 is an object to be transferred, 2
2 is a drive roller, and 23 is a bearing for the drive roller 22. Then, vibration of the vibrator 30 occurs in the Z-axis direction, and the drive roller 22 contacts the vibrator 30 at a contact angle θ with respect to the Z-axis direction. Arrow J is the transfer direction of the object to be transferred 21, arrow M1 is
is the direction of rotation of the auxiliary roller 18, and arrow M2 is the direction of rotation of the drive roller 22.

Next, a transfer device in which the rotational direction of the drive roller 22 can be controlled by two vibrators will be described. FIG. 16 is a diagram showing a first embodiment of a transfer device using two vibrators, and FIG. 17 is a diagram showing a second embodiment of a transfer device using two vibrators. In the figure, 31a, 31b are transducer units, 1a,
1b is the first arm, 2a, 2b are the second arms, 3a, 3
b is a sub-vibrator, 6a, 6b are mounting bolts, 7a, 7b are mounting pedestals, 8a, 8b are mounting flanges, 9a, 9b are piezoelectric elements for output pickup and vibration excitation, 18 is an auxiliary roller, 19, 23 is a bearing, 20 is a transfer rail, 2
1 is an object to be transported, and 22 is a drive roller.

In the transfer device configured as described above, when the vibrator unit 31a is driven, the sub-vibrator 3a vibrates in the Z1 axis direction, the drive roller 22 rotates in the direction of arrow M2, and the auxiliary roller 18 rotates in the direction of arrow M1. Then, the object 21 to be transferred is transferred in the direction of arrow J. Furthermore, when the vibrator unit 31b is driven, the sub vibrator 3b vibrates in the Z2 axis direction, the drive roller 22 rotates in the direction of arrow N2, and the auxiliary roller 18 rotates in the direction of arrow N1, causing the transferred object 21 to move in the direction of arrow N1. Transfer in direction K.

Further, the drive roller 22 contacts the sub-vibrator 3a at a contact angle θ1 and the sub-vibrator 3b at a contact angle θ2. Next, a transfer device for transferring an object placed on a table will be explained. FIG. 18 is a diagram showing a table-shaped transfer device using two vibrator units.

In the figure, 31a and 31b are transducer units, 1a and 1b are first arms, 2a and 2b are second arms, 3a and 3b are sub-oscillators, 6a and 6b are mounting bolts,
7a, 7b are mounting pedestals, 8a, 8b are mounting flanges, 9
a, 9b are piezoelectric elements for output pickup and vibration excitation, 18 is an auxiliary roller, 19 is a bearing, 25 is a sub-vibrator 3
The transducer unit support body, ie, the rail, which supports a and 3b, and 26 are the object support body, ie, the table.

[0049] In the transfer device having the above configuration, an object to be transferred placed on the table 26 is transferred. That is, when the transducer unit 31a is driven, the table 26 moves in the direction of the arrow J.
When the vibrator unit 31b is driven in the direction of arrow K, it moves in the direction of arrow K. The vibrator unit 31a vibrates in the Z-axis direction and contacts the rail 25 at a contact angle θ1, and the vibrator unit 31b vibrates in the Z2-axis direction and contacts the rail 25 at a contact angle θ2.

In the above embodiment, the rail 25 is fixed and the object to be transferred is transferred on the table 26, but it is also possible to fix the table 26 and place the object to be transferred on the rail 25. . 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. 6) as a general-purpose actuator in its drive section. That is, by using the rotational force output by the auxiliary roller 18 in FIGS. 13 to 17, a rotary motor can be constructed, and in the case of FIG. 18, a linear motor can be constructed as is.

According to the driving principle shown in FIG.
The vibrator unit 30 has a braking function and a holding function using frictional force when vibration is stopped, and enables highly accurate feeding and positioning. Therefore, in the case of a rotary motor, it can be used in the rotary table of a measuring instrument, the fine focus adjustment mechanism of a lens, the joint drive mechanism of an assembly robot, and in the case of a linear motor, it can be used in the positioning mechanism of a magnetic disk read head, a printer. It can be used in a head carriage drive mechanism, an XY plotter biaxial drive mechanism, or a pen vertical drive mechanism.

[0053]

As described in detail above, according to the present invention, the first arm is formed of an elastic body, the second arm is formed integrally with the first arm and extends at right angles, and the second arm is formed integrally with the first arm and extends at right angles to the first arm. It has a sub-vibrator integrally formed at the end of the arm, and a piezoelectric element is provided on the surface of the second arm parallel to the plane including the first arm and the second arm.

[0054] Therefore, since no bending vibration occurs in the first arm, the support means that supports the end of the first arm does not affect the vibration generated in the second arm, and a stable transfer force is maintained. can be generated. In addition, since two or more types of vibration with different vibration modes are not generated in any of the first arm, second arm, and sub-oscillator,
There is no interference between vibration modes, and stable vibration can be obtained, and there is no need to make the resonance frequencies of different vibration modes match or be close to each other, and the vibration modes are stabilized.

[0055] Furthermore, since a piezoelectric element is used in the drive section, the ultrasonic transport actuator can be made smaller and lighter. Furthermore, since the length of the second arm is greater than or equal to the length of the first arm, and the cross-sectional area of the second arm is larger than the cross-sectional area of the sub-oscillator, the vibration generated in the second arm is It is transmitted to the vibrator, the amplitude can be expanded, and the transfer speed can be increased.

[0056] Since the driving section is made into a unit by the first arm, the second arm, the sub-vibrator, and the piezoelectric element, it is not only easy to design the transfer device, but also to It can be applied not only to transporting objects, but also to rotary motors and linear motors.

[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 diagram showing an ultrasonic motor for paper feeding using a multi-mode vibrator that utilizes longitudinal vibration and bending vibration.

FIG. 3 is a diagram showing vibration modes of a multimode oscillator.

FIG. 4 is an explanatory diagram of an ultrasonic motor for paper feeding.

FIG. 5 is an explanatory diagram of each dimension of the vibrator.

FIG. 6 is a configuration diagram of an L-shaped vibrator unit.

FIG. 7 is a block diagram of a drive control circuit for controlling the vibrator unit.

FIG. 8 is a diagram showing vibration modes of a vibrator in the ultrasonic actuator for transportation according to the present invention.

FIG. 9 is a principle diagram of a mechanism for generating a transfer force in the ultrasonic transfer actuator of the present invention.

FIG. 10 is a vibration locus diagram of the contact point between the sub-oscillator and the transferred rotating body.

FIG. 11 is a diagram showing the relationship between the position and rotation direction of the rotating body to be transferred.

FIG. 12 is a diagram showing the relationship between the position of a flat object to be transported and the direction of transport.

FIG. 13 is a diagram illustrating a transfer device in which the transducer of the ultrasonic actuator for transfer of the present invention is brought into direct contact with the object to be transferred.

FIG. 14 is a diagram showing a first embodiment of a transfer device using a rotating body to be transferred.

FIG. 15 is a diagram showing a second embodiment of a transfer device using a rotating body to be transferred.

FIG. 16 is a diagram showing a first embodiment of a transfer device using two vibrators.

FIG. 17 is a diagram showing a second embodiment of a transfer device using two vibrators.

FIG. 18 is a diagram showing a table-shaped transfer device using two vibrator units.

[Explanation of symbols]

1 First arm 2 Second arm 3 Sub-oscillator 4 Fixed flange 5 Fixing hole 30 Vibrator

Claims (4)

[Claims] Claim 1: (a) a first arm made of an elastic body and generating first-order longitudinal torsional vibration when excited; (b)
(c) a second arm made of an elastic body, formed integrally with the first arm, extending at right angles, and generating secondary longitudinal bending vibration when excited; and (c) a second arm made of an elastic body and extending at right angles; (d) a sub-oscillator integrally formed at the end of the sub-oscillator, which forms a vibration node at the joint with the second arm to generate a primary longitudinal bending vibration when excited; a support means for supporting an end of the first arm; (e) a piezoelectric element provided on a surface of the second arm parallel to a plane including the first arm and the second arm; 2
An ultrasonic actuator for transport, characterized in that the length of the arm is longer than the length of the first arm, and (g) the cross-sectional area of the second arm is larger than the cross-sectional area of the sub-vibrator. 2. (a) a first arm made of an elastic body and generating first-order longitudinal torsional vibration when excited; (b)
(c) a second arm made of an elastic body, formed integrally with the first arm, extending at right angles, and generating secondary longitudinal bending vibration when excited; and (c) a second arm made of an elastic body and extending at right angles; (d) a sub-oscillator integrally formed at the end of the sub-oscillator, which forms a vibration node at the joint with the second arm to generate a primary longitudinal bending vibration when excited; a support means for supporting an end of the first arm; (e) a piezoelectric element provided on a surface of the second arm parallel to a plane including the first arm and the second arm; 2
(g) the cross-sectional area of the second arm is larger than the cross-sectional area of the sub-oscillator;
(h) A transfer device characterized in that a contact point between the sub-vibrator and the object to be transferred is located at a position offset from a line in the direction in which the sub-vibrator vibrates. 3. (a) a first arm made of an elastic body and generating first-order longitudinal torsional vibration when excited; (b)
(c) a second arm made of an elastic body, formed integrally with the first arm, extending at right angles, and generating secondary longitudinal bending vibration when excited; and (c) a second arm made of an elastic body and extending at right angles; (d) a sub-oscillator integrally formed at the end of the sub-oscillator, which forms a vibration node at the joint with the second arm to generate a primary longitudinal bending vibration when excited; a support means for supporting an end of the first arm; (e) a piezoelectric element provided on a surface of the second arm parallel to a plane including the first arm and the second arm; and (f) the sub-vibrator. and a drive roller rotatably disposed in contact with the surface of (g
) the length of the second arm is greater than or equal to the length of the first arm;
(h) The cross-sectional area of the second arm is larger than the cross-sectional area of the sub-vibrator, and (i) the center point of the drive roller is placed at a position offset from the line in which the sub-vibrator vibrates. A transfer device featuring: 4. (a) a first arm made of an elastic body and generating first-order longitudinal torsional vibration when excited; (b)
(c) a second arm made of an elastic body, formed integrally with the first arm, extending at right angles, and generating secondary longitudinal bending vibration when excited; and (c) a second arm made of an elastic body and extending at right angles; (d) a sub-oscillator integrally formed at the end of the sub-oscillator, which forms a vibration node at the joint with the second arm to generate a primary longitudinal bending vibration when excited; support means for supporting an end of the first arm; (e) a piezoelectric element provided on a surface of the second arm parallel to a plane including the first arm and the second arm; and (f) the first arm. (g) a transducer unit support for supporting the sub-vibrator; (h) the second arm; The first length is
(i) the cross-sectional area of the second arm is larger than the cross-sectional area of the sub-vibrator; and (j) the vibration direction of the sub-vibrator is inclined from the vertical direction. Transfer device.