JPH06121560A - Ultrasonic motor - Google Patents

Abstract

PURPOSE:To provide a downsized ultrasonic motor having highly reliable terminal which can be manufactured easily. CONSTITUTION:In the tubular ultrasonic motor, a ball receiver 2, a retainer 3, an output ring 5, a vibration isolating ring 6, a rotor 7, a stator 8 comprising an elastic body 8a and a piezoelectric body 8b, a viscoelastic adhesive 9, a vibration isolating member 10 for supporting member, a viscoelastic adhesive 9, a supporting plate 11, a coned disc spring 12, and a stop ring 13 are fit in this order to the outer peripheral face of a fixed frame 1 made of a short tubular body. A terminal 26 comprising a C-shaped flexible printed board having positioning holes 32a, 32b is secured to an electrode part provided on the piezoelectric body 8b and a high frequency voltage is applied from an ultrasonic motor drive circuit provided on a circuit board 27 through the terminal 26 to the electrode part of the piezoelectric body 8b.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrasonic motor, and more specifically, a stator for generating elliptical vibration on the surface of an elastic body using an electro-mechanical energy conversion element as a drive source.
The present invention relates to an ultrasonic motor having a rotor that is pressed against the stator and rotates.

[0002]

2. Description of the Related Art In a ring-shaped bending vibrator included in a ring-shaped ultrasonic vibrator, a flexible printed circuit board is used as an electrode for applying a voltage to an electrode surface of a piezoelectric body of the bending vibrator. The one used is
Various proposals have been made, one example of which is disclosed in Japanese Patent Laid-Open No. 63-64581. The ring-shaped bending oscillator described in this publication has a flexible printed circuit board having an arc-shaped connection terminal bonded to the electrode surface of its piezoelectric body, but does not particularly have positioning for bonding. The positioning is performed by matching the outer shapes of the flexible printed boards.

Another example of such a ring-shaped bending oscillator is disclosed in Japanese Patent Laid-Open No. 4-125075. In the ring-shaped bending oscillator described in this publication, a flexible printed board having a ring-shaped connection terminal is bonded to the electrode surface of the piezoelectric body with a conductive adhesive. Further, this flexible printed circuit board has a protruding terminal portion having one hole for ground connection.

[0004]

The problems described in the above two publications have the following drawbacks. That is,
Positioning when the flexible printed circuit board is bonded to the piezoelectric body must be based on the outer shape of the flexible printed circuit board as described above, and thus a large displacement may occur during bonding. Further, there is no disclosure of a method of attaching the tip terminal portion of the flexible printed board to the fixing member. Therefore, since there is nothing to position, a positional shift occurs. Furthermore, except for the fixed end of the terminal part, if vibration is not transmitted to other parts or if it is not firmly fixed, the vibration of the stator will be transmitted, and if another member comes into contact with it, for example, sound will be generated and energy loss will occur. In the above-described conventional example, the fixing position of the end of the flexible printed circuit board is not accurately determined, and the shape from the piezoelectric body to the end fixing position is difficult to determine, which may cause contact with other members. . In order to avoid such contact, there is a problem that a large clearance is required.

The present invention has been made in view of the above problems, and an object of the present invention is to provide an ultrasonic motor which is easy to manufacture, has a small size, and has a highly reliable terminal.

[0006]

In order to achieve the above object, an ultrasonic motor according to the present invention includes an elastic body and an elliptical surface on the elastic body which is fixed to the elastic body and to which a high frequency voltage is applied. A stator including an electro-mechanical energy conversion element that generates vibration, a support member that supports the stator to a fixed member so as not to hinder the vibration of the stator, and the ellipse that is pressed against the surface of the elastic body by a pressing member. A rotor that is rotationally driven by the vibration with respect to the stator, a bearing that rotatably supports the rotor on a fixed member, and at least two positioning members that are fixed to the electrode portion provided on the electro-mechanical energy conversion element. The high frequency voltage is applied to the electro-mechanical energy conversion element via the electrode portion, which is made of a flexible printed board having holes or notches. Characterized by comprising a terminal for pressurizing.

[0007]

The terminal applies a high frequency voltage to the electro-mechanical energy conversion element via the electrode section, and the electro-mechanical energy conversion element generates elliptical vibration on the surface of the elastic body by applying the high frequency voltage. Then, the rotor pressed against the surface of the elastic body by the pressing member is rotationally driven with respect to the stator by the elliptical vibration.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is an exploded perspective view of an ultrasonic motor showing a first embodiment of the present invention. This cylindrical ultrasonic motor has a ball bearing 2, a retainer 3, an output ring 5, an anti-vibration ring 6, and an outer peripheral surface of a fixed frame 1 which is a fixed member made of a short cylinder.
Rotor 7, Stator 8, Viscoelastic adhesive 9, Vibration isolating member 10 of support member, Viscoelastic adhesive 9, Support plate 11, Disc spring 1
2. A retaining ring 13 that constitutes a fixing member together with the fixing frame 1 is fitted in this order.

That is, the ball receiver 2 is formed in an annular shape, and its upper end face is abutted against the flange 1a formed on the upper end of the fixed frame 1 and is continuously provided under the flange 1a. Two notches 1 which are fitted to the fitting portion 1c on the inner peripheral surface and are provided at symmetrical positions on the circumference of the flange 1a.
Two protrusions 2a provided at the symmetrical position on the upper end surface side are engaged with and arranged at b.

Then, a U groove 2b having an inverted U-shaped cross section provided on the lower surface side of the ball receiver 2 and a U groove 5b provided on the upper surface of the output ring 5 so as to face the U groove 2b (see FIG. 3)), retainers 3 respectively holding balls 4 are arranged in a plurality of holes 3a formed at an equal angle position by an annular thin plate to form an annular thrust bearing 16. There is.

The output ring 5 has a step portion 5 on the lower surface side.
a is formed, the vibration isolating ring 6 is fitted to the step portion 5a, and the lower surface of the vibration isolating ring 6 is received by the step portion formed on the upper surface of the rotor 7. The rotating body 15 is shaped so that the centers of the rotor 5 and the rotor 7 coincide with each other. In addition, a stator 8 is provided on the lower surface of the rotor 7.
The upper surface on the side where the projection is provided is in contact.

The stator 8 including the piezoelectric body 8a and the elastic body 8b is partially formed of a flexible printed board on the lower surface side of the stator 8 to which the piezoelectric body 8a which is an electric-mechanical energy conversion element is joined. The terminals 26 are fixed (see FIG. 2), and the vibration isolating member 10 as a supporting member is further joined via the sheet of the viscoelastic adhesive 9.
When the stator 8 is fitted into the fixed frame 1, the terminal 26 bent in a U-shape is fitted into the notch 1i provided in the fixed frame 1 without coming into contact therewith.

On the other side of the vibration isolation member 10, that is, on the lower surface side, a support plate 11 made of an annular thin plate is joined via a sheet of viscoelastic adhesive 9, and the stator 8,
Driving body 1 in which a vibration isolator 10 and a support plate 11 are integrally laminated
4 are formed (see FIG. 3). In this driving body 14, the inner peripheral surface of the support plate 11 is fitted to the outer peripheral surface of the fixed frame 1, and the claws 1 provided at two symmetrical positions on the inner peripheral side of the support plate 11 are provided.
By engaging the engaging groove 1f provided on the outer peripheral surface of the lower portion of the fixed frame 1 with 1a, the fixed frame 1 is positioned so as not to rotate. In addition, the support plate 1 of the driving body 14
The lower surface of 1 is pressed by a disc spring 12 which is a pressing member.

As described above, the bearing 16, the rotating body 15, the driving body 14, and the disc spring 12 are incorporated in the fixed frame 1, and the retaining ring 13 is formed in the guide groove formed at three locations on the outer peripheral surface of the lower end portion of the fixed frame 1. Push it so that the claw 13a faces 1e,
Then, the claw 13a is rotated so as to fit into the groove 1d, and when the one claw 13a is fitted into the cut 1g, the disc spring 12 generates an appropriate crimping force. For the pressure adjustment, a spacer capable of selecting the thickness of the ring-shaped thin plate may be provided between the stop ring 13 and the disc spring 12.

Next, the structure of the piezoelectric body 8a will be described with reference to FIG. 4. As shown in FIG.
Is provided with polarized regions that are alternately polarized so that the polarization directions are indicated by + and-signs, and the upper end surface of such a piezoelectric body 8a, that is, the side bonded to the elastic body 8b. A plurality of electrodes corresponding to the above-mentioned polarization region are provided on the surface. Assuming that the bending vibration wavelength generated in the stator 8 is λ, the pitch lengths of the polarization patterns of + and − match the wavelength λ. The electrodes are roughly classified into an A-phase electrode 20 to which a high-frequency voltage is applied and a B-phase electrode 21 to which a high-frequency voltage having a 90 ° phase difference from that applied to the A-phase electrode 20 is applied. It

The A-phase electrode 20 has a length of 4λ, four positive polarized regions and four negative polarized regions are alternately provided along the circumferential direction. The divided electrodes 20a corresponding to the respective polarized regions + and −,
It has four 20b each. In addition, the B-phase electrode 21 is
It is arranged in a mirror-symmetrical position with respect to the A-phase electrode 20, and + and-polarized regions are also alternately formed, and electrodes 21a and 21b are provided respectively.

Then, the A-phase electrode 20 and the B-phase electrode 2
One of them is provided with a non-polarized non-polarized area having a length of λ / 4, and the corresponding non-polarized electrode 2
4 are provided. On the other hand, the A-phase electrode 20 and the B-phase electrode 2
Between 1 and the other, a length 2 of λ / 4 unpolarized
There are two non-polarized regions and a polarized region polarized to + with a length of λ / 4 provided at a position sandwiched by the non-polarized regions, and two ground electrodes are provided in the non-polarized region. 22
However, the monitor electrode 23 is provided in the + polarized region.

As shown in FIG. 4C, the other surface of the piezoelectric body 8a, that is, the lower end surface, has an A phase composed of one electrode at a position corresponding to the divided A phase electrode 20. The electrode 20c is provided, and the B-phase electrode 21 also has a similar B-phase electrode 21c at a corresponding position. Further, the non-polarized electrode 24, the ground electrode 22, the monitor electrode 23
For the non-polarized electrode 24 similar to these electrodes,
c, the ground electrode 22c, and the monitor electrode 23c are provided at corresponding positions on the lower end surface.

Here, in the ground electrode, as shown in FIG. 4B, the ground electrode 22 on the upper surface and the ground electrode 22c on the lower surface are connected and electrically connected by the connecting electrode 22a provided on the side surface. There is. The width W of the lead portion 22b from the ground electrode 22 to the connecting electrode 22a is
1 is formed to be narrower than λ / 8. Further, the width W2 of the connecting electrode 22a on the side surface is determined by
It is formed to have a relationship of λ / 4>W2> W1 with respect to the width W1 of b. This is a limitation so that the lead-out portion 22b can be formed by a simple method such as printing without short-circuiting with the electrodes on both sides of the ground electrode 22.

The upper surface (the surface shown in FIG. 1A) of the piezoelectric body 8a thus formed is made of a conductive material by using a conductive adhesive in which fine silver powder is dispersed in an epoxy resin. When bonded to the formed elastic body 8b, all the electrodes 20, 21, 22, formed on the upper surface of the elastic body 8b and the piezoelectric body 8a.
23 and 24 and the ground electrode 22c on the lower surface serve as the same potential surface. Then, four electrodes for connecting to an ultrasonic motor drive circuit provided on a circuit board 27 described later, that is, the A-phase electrode 20c, the B-phase electrode 21c, the monitor electrode 23c for detecting the vibration of the stator 8, and the ground. The electrode 22c is located on the lower surface side of the piezoelectric body 8a.

Next, a terminal 26 for electrically connecting the piezoelectric body 8a and a circuit board 27 described later will be described. The terminal 26 is provided on a base 63 (see FIG. 8) formed of a thin sheet of polyimide as shown by a region surrounded by a dotted line in FIG.
The surface of the copper foil pattern is gold-plated.

As shown in FIG. 5, the terminal 26 includes a piezoelectric body connecting portion 26a having a shape along the piezoelectric body 8a, a board connecting portion 26b for connecting to the circuit board 27, and these connecting portions. It has the connecting part 26c provided between 26a and 26b.

The piezoelectric body connecting portion 26a is composed of the piezoelectric body 8a.
Has a connecting electrode on its lower end surface for electrically connecting to each electrode provided on the. These connecting electrodes are
As indicated by the diagonal lines in FIG. 5, the monitor electrode 23
The G adhesive electrode 3 is provided in a rectangular shape slightly smaller than c or the like, and is connected to the monitor electrode 23c by the M adhesive electrode 31m and the G adhesive electrode 3 that is connected to the left electrode of the two ground electrodes 22c.
1g, A adhesive electrodes 31a, B connecting with A phase electrode 20c
It is a B adhesive electrode 31b connected to the phase electrode.

On the other hand, in the board connecting portion 26b, two positioning holes 32a, 32 for connecting with the circuit board 27 are provided.
b is drilled. One of these positioning holes 32a
Is provided with four electrodes around the hole, which are sequentially connected in the counterclockwise direction to the A adhesive electrode 31a.
B electrode 33 connected to electrode 33a and B adhesive electrode 31b
b, an M electrode 33m connected to the M adhesive electrode 31m, and a G electrode 33g connected to the G adhesive electrode 31g.

The four electrodes 3 of the piezoelectric connecting portion 26a
1a, 31b, 31g, 31m and the four electrodes 33a, 33b, 33g, 33m of the board connecting portion 26b are the four connecting patterns 34 provided in the connecting portion 26c.
They are electrically connected via a, 34b, 34g and 34m.

A terminal 26 having such a copper foil pattern
Insulation coating is applied to almost the entire surface, and the non-insulated part is the part shown by the diagonal lines in FIG.
Adhesive electrode 31a, B adhesive electrode 31b, M adhesive electrode 31
m, G adhesion electrode 31g and A electrode 33a, B electrode 33
b, G electrode 33g, and M electrode 33m.

The connection between such a terminal 26 and the piezoelectric body 8a will be described below. FIG. 5 is a partial view of the piezoelectric body 8a seen from the lower surface side, showing a state in which the terminal 26 is bonded to the electrode surface (see FIG. 4C) of the piezoelectric body 8a of the stator 8. A conductive adhesive in which fine silver powder is dispersed in an epoxy resin is used for adhesion, and as shown in the dotted portion in FIG. 4, there are five adhesion portions 35a, 35b, 35g, 35.
They are bonded by h and 35 m so that their bonded parts do not overlap each other. By such adhesion, A
The phase electrode 20c is electrically connected to the A electrode 33a, the B phase electrode 21c is electrically connected to the B electrode 33b, the monitor electrode 23c is electrically connected to the M electrode 33m, and the ground electrode 22c is electrically connected to the G electrode 33g.

When the terminal 26 is bonded to the electrode surface of the piezoelectric body 8a of the stator 8, if a jig as shown in FIG. 6 is used, the terminal 26 can be mounted with extremely high accuracy in the structure of this embodiment. Can be glued to.

That is, the above-mentioned adhesive portions 35a, 35b,
A pattern of a conductive adhesive of 35 g, 35 h, and 35 m is printed on the piezoelectric body 8 a of the stator 8 by means such as screen printing, and the stator 8 printed with this adhesive is shown in FIG.
As shown in, the inner diameter portion of the stator 8 is fitted and held on the stator holding base 42. At this time, the alignment of the stator 8 with respect to the stator holding base 42 in the circumferential direction is
The circumferential alignment portion 45 of the electrode pattern of the stator 8 is provided on the stator holding base 42 in the circumferential scale 44.
It is done according to.

Next, the positioning holes 32a, 32 of the terminal 26 are formed.
By fitting b to the positioning pin 41 projecting from the stator holding base 42, dropping the terminal 26, and applying a load to the bonding portion to bond, the bonding position can be determined by the accuracy of the jig. .

The terminal 26 as described above has two bending positions 36a and 3b of the connecting portion 26c shown in FIG.
6b, as shown in FIGS. 1 and 2, it is bent in a U-shape. The U-shaped forming of the terminal 26 also allows the positioning holes 32 a, 3 of the terminal 26 to be formed.
If a bending jig based on 2b is used, the accuracy is very high.

Although the terminal 26 is a flexible substrate based on a polyimide film or the like as described above,
By bending it into a U-shape, it becomes difficult to deform and the terminal 2
This is effective for accurately positioning the 6's. By bending the terminal 26 in a U shape, the strength of the terminal 26 is increased, while the U-shaped bent portion has a structure that allows the progressive bending vibration of the stator 8 with respect to the progressive bending vibration. ,
The terminal 26 does not interfere with the vibration of the stator 8.

Next, the connection between the terminal 26 and the circuit board 27 will be described. FIG. 7 is a perspective view showing a connecting portion between the terminal 26 and the circuit board 27. A drive control circuit portion of the ultrasonic motor is provided at an end portion (not shown) of the circuit board 27. Then, on the circuit board 27, the terminals 26 are provided.
Is provided with a connection portion 27a formed in a shape substantially similar to that of the board connection portion 26b of FIG.
On the surface opposite to 6, the four electrodes 47a, 47b, 47g, 4 corresponding to the four electrodes 33a, 33b, 33g, 33m of the substrate connecting portion 26b, which are substantially mirror-symmetrical to these, are provided.
7 m are provided, and wiring patterns electrically connected from these electrodes to the drive control circuit section are provided. Further, the connecting portion 27a is provided with positioning holes 48a and 48b having positions and shapes corresponding to the positioning holes 32a and 32b of the terminal 26.

The terminals 26 and the electrodes of the circuit board 27 are provided with positioning holes 32a, 48a and 32, respectively.
By arranging b and 48b at the same position, the respective terminal electrodes are arranged so as to face each other and be electrically connected to each other. As shown in FIG.
It is fixed by screwing the screw 29 to the screw portion 13b of the retaining ring 13 integrally fixed to the fixed frame 1 via the screw 0. Here, on the circuit board 27 side, since the electrodes are also gold-plated as described above, the contact resistance is small and extremely good conduction is achieved.

The pressure-bonding body 28 is made of a non-conductive rubber material such as silicon rubber, and at the same time the insulation of the joint portion is maintained, and at the same time, the vibration of the stator 8 is transmitted through the terminal 26 to the joint portion. It also works to prevent further transmission.

The operation of the ultrasonic motor configured as described above is the same as that of a conventional traveling wave type ultrasonic motor, and the drive signal output from the ultrasonic motor drive control circuit portion of the circuit board 27 is , 2 of the piezoelectric body 8a via the terminal 26
When high frequency voltages having 90 ° different phases are applied to the two electrodes, a bending traveling wave of, for example, 9 waves is generated in the stator 8 in this embodiment, and elliptical vibration is generated on the surface on which the protrusion is provided.
Then, since the protrusion is pressed against the rotor 7 by the disc spring 12, the rotating body 15 configured to be rotatable with respect to the fixed frame 1 is driven in the rotation direction of the elliptical vibration. Here, the rotor 7, the vibration isolation ring 6, and the output ring 5 that form the rotating body 15 are not joined, but when they are crimped, a frictional force is generated on each contacting surface, so that they rotate together. The rotation output of the rotating body 15 is taken out to the outside by engaging a protrusion of a driven body (not shown) with an output portion 5c forming a protruding engaging portion.

According to the first embodiment thus constructed, the two positioning holes 32a and 3 provided in the terminal 26 are provided.
By using 2b, the terminal 26 can be accurately and easily fixed to the stator 8 with high accuracy, and the end portion of the terminal 26 can be accurately fixed to the fixing member. Furthermore, the circuit board 27 and the terminal 26 can be connected by a simple and small mechanism. Since the positioning accuracy at the time of mounting is high as described above, a sufficient adhesion area of the terminal 26 can be secured, and a highly reliable terminal can be obtained. Further, the vibration of the stator 8 is not transmitted before the portion where the terminal 26 is attached to the retaining ring 13 integrated with the fixed frame 1, and the vibrating terminal portion contacts the fixed frame 1. Therefore, the vibration is not transmitted to other members, and an unpleasant sound is not generated. Further, since the space required for installing the terminal 26 itself can be reduced, the ultrasonic motor can be downsized.

In the first embodiment described above, the terminal 26 and the piezoelectric body 8a are adhered by using a conductive adhesive, but it is also possible to use a non-conductive adhesive. FIG. 8 shows a partial cross-sectional view of the bonded portion in this case. Piezoelectric body 8a
Is formed in a form in which a silver electrode 62 is projected on the piezoelectric ceramics 61.

On the other hand, in the terminal 26, a copper foil 64 is bonded onto a base 63 made of polyimide or the like via a copper foil bonding layer 65, and the surface of the copper foil 64 is covered with a gold plating layer 66. Further, the copper foil 64 is covered with an insulating cover lay 67 except for the electrically connected portion.

In this state, the surface of the terminal 26 or the piezoelectric body 8a is thinly and uniformly coated with a non-conductive adhesive agent 68 such as epoxy on the entire contact surface between the piezoelectric body 8a and the terminal 26 including the electrode surface. Bonding is performed using the bonding jig as shown in the first embodiment. At this time, when sufficient pressure is applied to the terminal 26 to be electrically connected and the electrode surface of the piezoelectric body 8a, the surface of the terminal 26 and the electrode surface are kept in electrical contact as shown in FIG. Glued in.

By carrying out such a bonding method, the bonding area between the piezoelectric body and the terminal becomes wider than that shown in the first embodiment, and more stable and strong bonding can be carried out.

9 and 10 show a second embodiment of the present invention. The second embodiment has substantially the same configuration as the first embodiment described above, members having the same functions are designated by the same reference numerals, and the description thereof will be omitted. Only the differences will be described. The difference between the second embodiment and the first embodiment is the shape of the terminal. The terminal 51 includes an arc-shaped connecting portion 51b that connects to the piezoelectric body 8a, a disc-shaped electrode portion 51a that extends upward from the connecting portion 51b, and a circle that extends downward from the connecting portion 51b. It has a plate-shaped electrode portion 51c.

The connecting portion 51b is a portion having substantially the same function as that of the piezoelectric connecting portion 26a of the terminal 26 of the first embodiment, and the M adhesive electrode 31m connected to the monitor electrode 23c and the two grounds. 31 g of G adhesion electrodes connected to the electrode on the right side of the electrode 22c, A connected to the A phase electrode 20c
Adhesive electrode 31a, B adhesive electrode 31b connected to the B-phase electrode
Are provided respectively.

In the electrode portion 51c, an A electrode 33a connected to the A adhesive electrode 31a, a B electrode 33b connected to the B adhesive electrode 31b, and an M electrode 33m connected to the M adhesive electrode 31m are formed in the central portion. It is provided along the circumference of the provided positioning hole 52c. And this electrode portion 51c
The U-shaped notch 53 is provided on the opposite side of the connection portion 51b of the.
c is provided.

The electrode portion 51a is provided on almost one surface of the electrode portion 51a except for the edge portion thereof so that the G electrode 33g connected to the G adhesive electrode 31g surrounds the circumference of the positioning hole 52a. A U-shaped cutout 53a is provided on the opposite side of the connecting portion 51b of the electrode portion 51a.

Adhesion of the terminal 51 to the piezoelectric body 8a is performed by using the same method as in the first embodiment. After the terminal 51 is adhered to the piezoelectric body 8a, the electrode portion 51c on the inner diameter side is bent at a bending position 54 and the electrode portion 51 on the outer diameter side is 180 degrees.
Positioning holes 52a and 52c and notches 53a and 53c provided in the electrode portions 51a and 51c, respectively.
So that they overlap. At this time, the electrode portion 51a and the electrode portion 5
1c may be fixed by bonding with an adhesive or the like. By doing so, the G electrode 33g is arranged on the back surface (in FIG. 9), while the A electrode 33a, the M electrode 33m, and the B electrode 33b are arranged on the front surface (in FIG. 9).

FIG. 10 shows the stator 8 constructed as described above.
Assemble as. The position of the terminal 51 is fastened to the fixed portion 1j which is a part of the fixed frame 1 by the screw 29 through the positioning holes 52a and 52c of the terminal 51, while the notch 53 is formed.
The a and 53c are engaged with the projections 1h of the fixed portion 1j to be positioned and fixed at a predetermined position.

At this time, the A, M, B electrodes 33a, 33m,
A circuit board 27 having similar electrodes at a position facing these electrodes is brought into contact with 33b, and pressure is applied by screwing a screw 29 into the fixing portion 1j via a washer 30 which forms a disc spring, so that it is more reliable. Electrodes are connected.

On the other hand, for the ground electrode, the terminal 51
The G electrode 33g is in contact with the fixing portion 1j made of a conductive material, and the screws 29 and the washers 30 are also made of a conductive material.
It is electrically connected to a ground electrode provided on the surface of the circuit board 27. At this time, the fixed portion 1j is connected to the ground electrode, and if the circuit ground is connected to the fixed portion 1j at another portion, a common ground line can be easily formed.

The operation of the second embodiment is the same as that of the first embodiment.
It is almost the same as the embodiment. The second embodiment is the same as the first embodiment.
In addition to having the same effect as the embodiment, the connection of the terminal 51 is made in a smaller space as compared with the first embodiment,
Furthermore, it is advantageous in terms of space.

Even if the shape of the terminal is the same as that of the first embodiment,
If the G electrode is provided on the surface opposite to the terminal, the positioning hole is formed as a through hole, and the terminal is formed as a double-sided board, the ground can be connected to the fixing portion 1j as in the second embodiment. Also, in the second embodiment, the screw 29 and the circuit board 27 are connected via the washer 30, but
This is also possible by using a conductive rubber such as zebra rubber.

Further, in the first and second embodiments, only the circular traveling-wave type ultrasonic motor is described, but the present invention is not limited to this, and the electrodes of the piezoelectric body to the flexible printed circuit board are used. It is needless to say that the present invention can be applied to all types of ultrasonic motors in which the power supply terminal is pulled out by using.

[0053]

As described above, according to the present invention, it is possible to provide an ultrasonic motor which is easy to manufacture, has a small size, and has a highly reliable terminal.

[Brief description of drawings]

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

FIG. 2 is an enlarged perspective view of a portion A showing a connecting portion between the terminal and the stator shown in FIG.

FIG. 3 is a sectional view showing the left half of the ultrasonic motor of the first embodiment.

FIG. 4 is a plan view (A) of the piezoelectric body of the first embodiment,
(B) Side view, (C) Bottom surface.

FIG. 5 is a perspective view showing the connection between the terminals and the piezoelectric body according to the first embodiment.

FIG. 6A is a front view and FIG. 6B is a BB sectional view showing a method of fixing the terminal of the first embodiment to a piezoelectric body.

FIG. 7 is a perspective view showing a connection portion between the terminal and the circuit board according to the first embodiment.

FIG. 8 is a cross-sectional view illustrating a state where the piezoelectric body and the terminal according to the first embodiment are bonded with a non-conductive adhesive.

FIG. 9 is a plan view of a terminal showing a second embodiment of the present invention.

FIG. 10 is a sectional view showing a mounting portion of the terminal of the second embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Fixed frame 7 ... Rotor 8 ... Stator 8a ... Piezoelectric body (electrical-mechanical energy conversion element) 8b ... Elastic body 10 ... Antivibration member (supporting member) 12 ... Disc spring (pressurizing member) 13 ... Stop ring 16 ... Bearing 20c ... A phase electrode 21c ... B phase electrode 26 ... Terminals 32a, 32b ... Positioning hole 51 ... Terminals 53a, 53c ... Notch for positioning

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[Procedure amendment]

[Submission date] May 7, 1993

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be amended] Claims

[Correction method] Change

[Correction content]

[Claims]

Claims (1)

[Claims] 1. A stator comprising an elastic body and an electro-mechanical energy conversion element which is fixed to the elastic body and generates elliptical vibration on the surface of the elastic body when a high frequency voltage is applied thereto, and a vibration of the stator. A support member that supports the stator to a fixed member so as not to hinder the rotor, a rotor that is pressed against the surface of the elastic body by a pressure member, and is rotationally driven with respect to the stator by the elliptical vibration, and the rotor is fixed. A bearing that rotatably supports the member and a flexible printed circuit board that has at least two positioning holes or notches and is fixed to the electrode portion provided on the electro-mechanical energy conversion element. An ultrasonic motor comprising: a terminal for applying the high frequency voltage to the electro-mechanical energy conversion element;