JP3485779B2 - Wiring structure of ultrasonic motor and annular flexible substrate for piezoelectric element - Google Patents

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 particularly to a wiring structure for supplying a high frequency voltage to, for example, a piezoelectric element.

[0002]

2. Description of the Related Art As a conventional ultrasonic motor, for example, there is one disclosed in Japanese Patent Publication No. 7-10188 (Japanese Patent Laid-Open No. 63-64581). A flexible substrate (flexible printed circuit board) is bonded to an annular piezoelectric element (electrical-mechanical energy conversion element) attached to the stator of the ultrasonic motor in order to supply a high frequency drive voltage to the piezoelectric element. Has been done.

A conductor (conductor pattern) is provided on the flexible substrate. A comb-tooth connecting portion extending in the circumferential direction of the piezoelectric element is formed on the conductor, and a comb-tooth-like contact portion extending from the comb-tooth connecting portion toward the inside in the radial direction of the piezoelectric element is formed. Then, the comb tooth connecting portion and the contact portion are bonded to a predetermined electrode plate of the piezoelectric element.

In such an ultrasonic motor, a high frequency drive voltage is supplied to the piezoelectric element through the comb-teeth connecting portion and the comb-teeth-shaped contact portion of the conductor. Then, the piezoelectric element vibrates,
Traveling wave vibration is generated on the contact surface of the stator with the rotor based on the vibration of the piezoelectric element. The rotor rotates based on the traveling wave vibration.

Here, the conductors at the positions to be adhered to the electrode plate of the piezoelectric element are the comb-teeth connecting portion and the contact portion, and the contact portion has a comb-teeth shape divided into a plurality in the circumferential direction. Therefore, the comb-shaped conductor does not significantly suppress the vibration of the piezoelectric element.

[0006]

By the way, the vibration of the piezoelectric element of the ultrasonic motor and the traveling wave vibration at the contact surface of the stator with the rotor become stronger toward the outer side in the radial direction. However, since the comb-teeth connecting portion extending in the circumferential direction of the piezoelectric element is formed outside the comb-teeth-shaped contact portion in the conductor at the position where it is bonded to the electrode fixed to the piezoelectric element, the comb-teeth connecting portion is formed. There is a problem that the part suppresses strong vibration of the piezoelectric element and strong traveling wave vibration of the stator. This causes the maximum output of the ultrasonic motor to be suppressed.

The present invention has been made to solve the above problems, and an object thereof is to reduce the suppression of vibration of the piezoelectric element and to improve the maximum output of the ultrasonic motor. It is an object to provide a wiring structure for a motor and an annular flexible substrate for a piezoelectric element.

[0008]

According to a first aspect of the present invention, a predetermined electrode plate is fixed to a ring-shaped piezoelectric element which is provided in a stator and which generates vibration for rotating a rotor. In a wiring structure of an ultrasonic motor, in which a flexible substrate is fixed to and a conductor provided on the flexible substrate electrically connects to the piezoelectric element,
The portion of the conductor fixed to the electrode plate is the piezoelectric element.
A comb tooth connecting portion that is formed inside an intermediate circle between the inner circumference and the outer circumference of the child and extends in the circumferential direction of the piezoelectric element, and extends from the comb tooth connecting portion to the outer side in the radial direction of the piezoelectric element. It has a comb tooth-shaped contact portion divided into a plurality in the circumferential direction.

The invention according to claim 2 is, in the wiring structure of the ultrasonic motor according to claim 1, characterized in that the electrode plate to which the conductor is fixed is a driving electrode plate. According to a third aspect of the invention, in the wiring structure of the ultrasonic motor according to the first or second aspect, the comb tooth connecting portion is
The gist is that the piezoelectric element is formed inside an intermediate circle between the inner circumference and the outer circumference.

The invention according to claim 4 is the invention according to claim 1 or 2.
In the wiring structure of the ultrasonic motor described in [1], the gist is that the comb-teeth connecting portion and the comb-teeth-shaped contact portion are formed inside an intermediate circle between the inner circumference and the outer circumference of the piezoelectric element.

The invention as defined in claim 5 is defined by claim 1 through claim 4.
In the wiring structure of the ultrasonic motor according to any one of items 1 to 3, the comb-teeth connecting portion and the comb-teeth-shaped contact portion are configured to come into contact with a part of the electrode plate extending in the circumferential direction with a predetermined length. The main point is to form.

According to a sixth aspect of the invention, the piezoelectric element is fixed to a predetermined electrode plate that is fixed to the annular piezoelectric element, and is electrically connected to the piezoelectric element by a conductor provided on the fixed surface. in annular flexible substrate for the piezoelectric element, the portion which is fixed to the electrode plate of the conductor, the pressure
When it is formed inside the middle circle between the inner circumference and the outer circumference of the electric element
Both have comb-teeth connecting portions that extend in the circumferential direction of the piezoelectric element, and comb-teeth-shaped contact portions that extend from the comb-teeth connecting portion to the outside in the radial direction of the piezoelectric element and are divided into a plurality of pieces in the circumferential direction. Is the gist.

According to the first aspect of the present invention, the comb-teeth connecting portion and the contact portion are formed in the portion of the conductor fixed to the electrode plate, and the contact portion is divided into a plurality of portions in the circumferential direction of the piezoelectric element. Since the contact portion has a comb shape, it is possible to reduce the possibility that the contact portion suppresses the vibration of the piezoelectric element. Further, the comb tooth connecting portion is formed radially inward of the comb tooth-shaped contact portion. Therefore, the outer end of the contact portion becomes a free end, and the comb-teeth connecting portion is less likely to suppress strong vibration generated on the outer side in the radial direction of the piezoelectric element.

According to the second aspect of the invention, the electrode plate to which the conductor is fixed is a driving electrode plate. Therefore, it is possible to reduce the possibility that the conductor that needs to have a large contact area for contacting the electrode plate in order to apply the high frequency voltage suppresses the vibration of the piezoelectric element.

According to the third aspect of the invention, since the comb-teeth connecting portion is formed inside the middle circle between the inner circumference and the outer circumference of the piezoelectric element, the conductor of the portion fixed to the electrode plate is piezoelectric. It is further reduced to suppress the strong vibration generated on the outer side in the radial direction of the element.

According to the fourth aspect of the present invention, since the comb-teeth connecting portion and the comb-teeth-shaped contact portion are formed inside an intermediate circle between the inner circumference and the outer circumference of the piezoelectric element, the electrode plate is formed. It is further reduced that the conductor of the fixed portion suppresses the strong vibration generated on the outer side in the radial direction of the piezoelectric element.

According to the fifth aspect of the present invention, the comb-teeth connecting portion and the comb-teeth-shaped contact portion are formed so as to come into contact with a part of the electrode plate extending in the circumferential direction with a predetermined length. Therefore, the portion where the comb-teeth connecting portion and the comb-teeth-shaped contact portion suppress the vibration of the piezoelectric element becomes small. Therefore, it is further reduced that the conductor of the portion fixed to the electrode plate suppresses the vibration of the piezoelectric element.

According to the sixth aspect of the invention, the comb-teeth connecting portion and the contact portion are formed in the portion of the conductor fixed to the electrode plate, and the contact portion is divided into a plurality of portions in the circumferential direction of the piezoelectric element. Further, since it has a comb-teeth shape, it is reduced that the contact portion suppresses vibration generated in the piezoelectric element. Further, the comb tooth connecting portion is formed radially inward of the comb tooth-shaped contact portion. Therefore, the outer end of the contact portion becomes a free end, and the comb-teeth connecting portion is less likely to suppress strong vibration generated on the outer side in the radial direction of the piezoelectric element.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is embodied in a traveling wave type ultrasonic motor will be described below with reference to FIGS.

FIG. 1 shows a sectional view of an ultrasonic motor. The housing 2 of the ultrasonic motor 1 is composed of a base 3 and a cover 4. The base 3 has a bearing holding portion 3a for holding the ball bearing 5, and the bearing holding portion 3a.
A bulging portion 3b formed to extend inward from the inner open end of
A through hole 3c for inserting the rotary shaft 6 is provided.
The bulged portion 3b is provided with a screw hole 3d for fixing the stator 10 described later.

A bearing holding portion 4a for holding the slide bearing 7 is formed on the upper portion of the cover 4, and a through hole 4b for inserting the rotary shaft 6 is formed in the central portion thereof. Then, the rotary shaft 6 includes the bearing holding portion 3a,
It is rotatably supported with respect to the housing 2 via a radial ball bearing 5 and a slide bearing 7 which are respectively held by 4a.

An annular insulating plate 8 for inserting the rotary shaft 6 is placed on the upper surface of the bulging portion 3b of the base 3.
Further, a stator 10 brazed with an annular metal substrate 9 is mounted on the upper surface thereof.

The stator 10 is made of a rolled steel plate, for example, a cold rolled steel plate (SPCC), and a through hole 10a for inserting the rotary shaft 6 is formed in the center thereof.
In the stator 10, a portion corresponding to the bulging portion 3b of the base 3 is a fixing portion 10b, and a screw through hole 10c is provided at a position of the fixing portion 10b corresponding to the screw hole 3d of the bulging portion 3b. ing. Further, the cross section of the outer peripheral portion of the stator 10 is bent in a crank shape, the upwardly bent portion is an extension portion 10d, and the portion horizontally extended outward from the tip of the extension portion 10d is a vibration plate portion 10e. There is.
Further, in the stator 10, a horizontal portion connecting the vibrating plate portion 10e and the fixed portion 10b via the extending portion 10d is a vibration damping portion 10f. An annular base ring 11 is joined to the lower surface of the outer peripheral portion of the stator 10 in the extending portion 10d by brazing. The piezoelectric element 12 to be described later is provided on the lower surface of the base ring 11.
Etc. are adhered with an adhesive.

The stator 10 has the screw through hole 10
The screw 13 is inserted into the c, and the tip of the screw 13 is fixed to the base 3 by being screwed into the screw hole 3d provided in the bulging portion 3b of the base 3. Incidentally, the screw through hole 10
c and the screw 13 are connected via an insulating washer 14, and the stator 10 and the bulging portion 3b of the base 3 are
The insulating plate 8 and the insulating washer 14 provide an electrically insulated state.

A rotor 16 made of stainless steel or aluminum alloy provided with a lining material 15 is arranged on the upper surface of the stator 10 so as to come into contact with the upper surface of the vibrating plate portion 10e.

The rotor 16 has a fitting hole 16 in its center.
a is formed. An insulating collar 17 is fitted in the fitting hole 16a. The insulating collar 17 and the rotor 16 are assembled so that they cannot rotate relative to each other. Further, the insulating collar 17 has a fitting hole 17a formed at the center thereof. The rotary shaft 6 is fitted and connected to the fitting hole 17a so as not to rotate relative to the rotary shaft 6. That is, the rotor 16 is non-rotatably attached to the rotary shaft 6 via the insulating collar 17.

The upper surface of the insulating collar 17 is pressed against a pressing elastic member 18 including a disc spring 18a and a plate 18b. The pressurizing elastic member 18 is connected to the rotating shaft 6 so as not to be rotatable and further so as not to be able to move upward by a circlip 19. The elastic force of the pressurizing elastic member 18 causes the rotor 16 to move to the stator 1
It is pressed against 0.

As shown in FIG. 2, the piezoelectric element 12 is divided into 20 pieces so that the polarities adjacent to each other in the circumferential direction are opposite to each other and subjected to polarization treatment. More specifically, the piezoelectric element 12 has first polarized region groups A1 to E8 that are polarized into eight at equal intervals.
A8 and second polarized region groups B1 to B8 that have been polarized into eight at equal intervals are formed. The first polarized region group A1 to A8 and the second polarized region group B1 to B8 are 90 in each group. ° It is arranged with a predetermined interval so that traveling wave vibration is generated when voltages with a phase shift are applied.

A feedback polarization region F is provided between the first polarization region A1 which is one end of the first polarization region group A1 to A8 and the second polarization region B1 which is one end of the second polarization region group B1 to B8. It is formed so as to be sandwiched between the two connected polarization regions R1 and R2. In addition, the first polarization region groups A1 to A8
The other end of the first polarized region A8 and the second polarized region group B1
A connection polarization region R3 is formed between the second polarization regions B8 which is the other end of B8. The feedback polarization region F includes the first and second polarization region groups A1 to A8 and B1.
A detection voltage based on the vibration generated at B8 is generated.

An electrode plate 20 is provided on the lower surface of the piezoelectric element 12. The electrode plate 20 is fixed to the piezoelectric element 12 by printing or baking. The electrode plate 20 includes a first electrode plate 20a as a driving electrode plate corresponding to the positions of the first polarization region groups A1 to A8 and a driving electrode plate corresponding to the positions of the second polarization region groups B1 to B8. Second electrode plate 20 as
b, the connecting electrode plates 20r1 to 20r3 respectively corresponding to the positions of the connecting polarization regions R1 to R3, and the feedback electrode plate 20 corresponding to the position of the feedback polarization region F.
There is f.

A flexible substrate 21 is fixed to the lower surface of the electrode plate 20. The flexible substrate 21 includes a flexible plate 22 made of a polyimide resin, a conductor 23 fixed to the upper surface of the flexible plate 22, and a cover lay 24 made of a polyimide resin adhered to the upper surface of the flexible plate 22 to which the conductor 23 is fixed. It consists of and.

As shown in FIG. 3, the flexible plate 22 corresponds to an annular ring portion 22a corresponding to the lower surface of the electrode plate 20, and a portion below the metal substrate 9 from the inner peripheral side of the ring portion 22a. Inner extension part 22b extended to the position
And an outer extending portion 22c extending radially outward from the outer peripheral side of the ring portion 22a in which the inner extending portion 22b is formed.

The conductor 23, as shown in FIG.
It is composed of an electrode conductor 25, a second electrode conductor 26, a feedback conductor 27, and a ground conductor 28.

The tip end 27a of the feedback conductor 27 is formed on the ring portion 22a corresponding to the feedback electrode plate 20f. Further, the feedback conductor 27 is formed with a connecting portion 27b extending from the tip portion 27a thereof to the end portion of the outer extending portion 22c through the center on the outer extending portion 22c. A comb-teeth-shaped contact portion 27c divided in the circumferential direction of the ring portion 22a is formed on the tip portion 27a of the feedback conductor 27.

The ground conductor 28 is formed so as to sandwich both sides of the feedback conductor 27.
More specifically, the ground conductor 28 has a tip portion 28a.
Are formed on the inner extending portion 22b corresponding to the lower side of the metal substrate 9. The ground conductor 28 is formed with a constricted portion 28b from the tip end portion 28a toward the feedback conductor 27. In addition, the ground conductor 28 is formed with cut-off connecting portions 28c and 28d that branch from the constricted portion 28b so as to sandwich both sides of the feedback conductor 27 and extend to the end of the outer extending portion 22c. There is. It should be noted that a comb tooth-shaped contact portion 28e divided in the circumferential direction is formed on the tip end portion 28a of the ground conductor 28, and the comb tooth-shaped contact portion 28 is formed.
The constricted portion 28b is formed from a comb-teeth connecting portion 28f that connects e in the circumferential direction.

The first and second electrode conductors 25, 26
Are formed on both sides of the ground conductor 28.
More specifically, the first electrode conductor 25 has a tip portion 25a.
Is a ring portion 2 corresponding to one end of the first electrode plate 20a.
It is formed on 2a. Then, the first electrode conductor 25
A connecting portion 25b extending from the tip portion 25a to the end portion of the outer extending portion 22c is formed along one side (right side in FIG. 4) of the cutoff connecting portion 28c of the ground conductor 28. The second electrode conductor 26 has a tip portion 26.
a is formed on the ring portion 22a corresponding to one end of the second electrode plate 20b. Then, the second electrode conductor 2
6 includes a conductor 28 for ground from the tip portion 26a thereof.
A connecting portion 26b is formed along the other side (left side in FIG. 4) of the cutoff connecting portion 28d to the end of the outer extending portion 22c.

Comb-shaped contact portions 25c, 26c divided in the circumferential direction of the ring portion 22a are formed at the tip portions 25a, 26a of the first and second electrode conductors 25, 26, respectively. . More specifically, the tip end portions 25a and 26a are formed with comb-tooth connecting portions 25d and 26d extending along the inner peripheral side of the ring portion 22a to predetermined positions.
Comb-tooth-shaped contact portions 25c and 26c, which are divided in the circumferential direction and extend outward from the comb-teeth connecting portions 25d and 26d in the radial direction of the ring portion 22a, are formed.
In the present embodiment, the comb tooth connecting portions 25d and 26d are
The ring portion 22a is formed inside the middle circle between the inner circumference and the outer circumference.

As shown in FIGS. 3 and 5, the cover lay 24 has a shape in which an annular shape is partially cut away, and the conductor 23 is formed.
The reinforcing portion 24a is formed so as not to overlap with the cover portion 24b, and the cover portion 24b is formed so as to substantially cover the conductor 23 at a partly cut away portion.

The cover portion 24b has the first and second electrode conductors 25 and 26, as shown by the alternate long and short dash line in FIG.
The feedback conductor 27 and the ground conductor 28 are formed so as to protect portions other than the respective tip portions 25a to 28a. That is, the cover portion 24b is formed such that the respective tip portions 25a to 28a are exposed on the upper surface of the flexible substrate 21. The tip portion 27a of the feedback conductor 27 is exposed on the upper surface of the flexible substrate 21 through a window portion 24c formed through the cover portion 24b. In addition, the window portion 24c has the connection electrode plate 20r.
A part of the ground conductor 28 at a position corresponding to 1, 20r2 is formed so as to be exposed on the upper surface of the flexible substrate 21. Further, the cover portion 24b is provided with the outer extending portion 2
The ends of the conductors 23 (25 to 28) at the ends of 2c are formed so as to be exposed on the upper surface of the flexible substrate 21.

The ring portion 22 is provided on the reinforcing portion 24a.
A plurality of balance maintaining parts 24d having a width from the inner circumference to the outer circumference of a, and connection details 24 connecting the plurality of balance maintaining parts 24d in the circumferential direction on the ring part 22a.
e are formed.

The plurality of balance maintaining sections 24d are shown in FIG.
As shown in FIG. 1, one wavelength interval of vibration generated in each of the first and second polarization region groups A1 to A8 and B1 to B8 of the piezoelectric element 12, that is, the first and second polarization region group A1. To A8 and B1 to B8 are formed at intervals of two polarization-processed regions. Then, each balance maintaining unit 24d includes the first and second polarization region groups A.
1 to A8 and B1 to B8 are arranged at positions relatively unlikely to interfere with traveling wave vibrations. In addition, in the present embodiment, seven balance maintaining portions 24d are formed, and each of them has a width substantially the same as the circumferential width of the connection polarization region R3. And one of them is the connected polarization region R
It is arranged at a position corresponding to 3 and other balance maintaining unit 24
Three d's are arranged symmetrically about the connected polarization region R3.

The flexible substrate 21 having the above-described structure is provided with the tip portions 25a to 27 of the conductors 25 to 27.
It is fixed to the lower surface of the electrode plate 20 so that a is fixed to the corresponding electrode plates 20a, 20b, 20f. At this time, the inner extending portion 22b is bent obliquely upward as shown in FIG. 1, and the contact portion 28e of the ground conductor 28 on the inner extending portion 22b is formed on the metal substrate 9. It is fixed to the bottom surface. That is, the inner extending portion 22b
The front end portion of the above is interposed between the metal substrate 9 and the insulating plate 8 in the assembled state.

Then, the exposed conductor 23 (25 to 2) at the end of the outer extending portion 22c of the flexible substrate 21.
The end of 8) has a connector 29 attached to the cover 4.
To the respective lead wires 30. The connector 29 is connected to a controller (not shown) for supplying a high frequency drive voltage for driving and controlling the ultrasonic motor 1.

In the ultrasonic motor 1 configured as described above, when a predetermined high frequency drive voltage is applied from the controller, the first and second electrode conductors 25 and 26, and the first electrode conductors
And 90 ° to the respective polarization region groups A1 to A8 and B1 to B8 of the piezoelectric element 12 via the second electrode plates 20a and 20b.
Voltages out of phase are supplied. Then, the piezoelectric element 1
2 vibrates to generate traveling wave vibration in the vibration plate portion 10e, which is a contact surface with the rotor 16 via the base ring 11 and the extending portion 10d of the stator 10. Then, the rotor 16 pressed against the vibrating plate portion 10e rotates based on the traveling wave vibration, and rotates the rotating shaft 6.

Next, the characteristic effects of the ultrasonic motor configured as described above will be described below. (1) In the present embodiment, the first and second electrode plates 20a,
First and second electrode conductors 25 and 26 fixed to 20b
The tip end portions 25a and 26a of the
d, 26d and comb tooth-shaped contact portions 25c, 26c are formed. The comb-shaped contact portions 25c and 26c are
Since it has a comb-like shape divided into a plurality in the circumferential direction, it is reduced that the contact portions 25c and 26c suppress the vibration of the piezoelectric element 12.

Furthermore, the comb-teeth connecting portions 25d and 26d extending in the circumferential direction of the piezoelectric element 12 are comb-teeth-shaped contact portions 25c and 26.
It is formed radially inward of c. That is, the outer ends of the comb-shaped contact portions 25c and 26c are free ends. Therefore, it is reduced that the comb tooth connecting portions 25d and 26d suppress strong vibrations that are vibrations generated on the outside in the radial direction of the piezoelectric element 12. As a result, the maximum output of this ultrasonic motor can be improved.

(2) Further, in the present embodiment, the high-frequency voltage is applied and the tip portions 25a and 26a of the first and second electrode conductors 25 and 26, which need to have a large contact area, are formed of the piezoelectric element 12. Since it becomes difficult to suppress vibration, the piezoelectric element 12
The part that suppresses the vibration of is greatly reduced.

(3) Further, the comb tooth connecting portions 25d and 26d
Is formed inside the middle circle between the inner circumference and the outer circumference of the piezoelectric element 12, the comb-tooth connecting portions 25d and 26d and the comb-tooth-like contact portions 25c and 26c are located outside the piezoelectric element 12 in the radial direction. It is further reduced to suppress the strong vibration that is the generated vibration.

(4) Furthermore, in the present embodiment, the comb tooth connecting portions 25d and 26d and the comb tooth-shaped contact portions 25c and 2 are formed.
6c is formed corresponding to one end of the first and second electrode plates 20a, 20b. Therefore, the comb tooth connecting portions 25d, 2
6d and the comb-shaped contact portions 25c and 26c are the first and the second.
As compared with the case where the electrode plates 20a and 20b are formed over the entire area, the portion that suppresses the vibration of the piezoelectric element 12 becomes smaller. Therefore, the comb-teeth connecting portions 25d and 26d and the comb-teeth-shaped contact portions 25c and 26c are suppressed from suppressing the vibration of the piezoelectric element 12. Also, the comb tooth connecting portion 25
The material cost of the conductor 23 can be reduced as compared with the case where the d and 26d and the comb-shaped contact portions 25c and 26c are formed over the entire first and second electrode plates 20a and 20b.

(5) In this embodiment, the reinforcing portion 2 is provided in the portion of the flexible substrate 21 where the conductor 23 is not formed.
4a is formed. In the reinforcing portion 24a, the conductor 23 slightly suppresses a part of the vibration in the circumferential direction as described above, while the conductor 23 slightly suppresses the vibration in the other part so as to keep the balance of the vibration in the circumferential direction. A plurality of balance maintaining portions 24d for suppressing are formed. Further, the reinforcing portion 24a is formed with a thin connecting detail 24e for connecting the plurality of balance maintaining portions 24d in the circumferential direction so as not to suppress vibration. Therefore, although the conductor 23 slightly suppresses a part of the circumferential vibration as described above, the balance maintaining portion 24d
Improves the balance of vibration in the circumferential direction, and the connection details 24e
Secures its rigidity so that the flexible substrate 21 can be easily handled. As a result, the flexible substrate 2 is improved while evenly improving the maximum output of this ultrasonic motor.
It is possible to secure the rigidity of No. 1 and facilitate its handling.

(6) In this embodiment, the cutoff connecting portions 28c and 28d of the ground conductor 28 are formed so as to sandwich both sides of the feedback conductor 27. Therefore, the detection voltage of the vibration generated in the feedback polarization region F is less likely to be affected by the noise based on the high frequency drive voltage generated from the first and second electrode conductors. As a result, the ultrasonic motor 1 can perform accurate feedback control with the detected voltage.

The above embodiment may be modified as follows. The flexible board 21 of the above embodiment may be changed to a flexible board 31 as shown in FIG. 6, for example. In the flexible substrate 31, the comb-teeth connecting portions 32a and 33a of the first and second electrode conductors 32 and 33 and the comb-teeth-shaped contact portions 32b and 33b are provided on the first and second electrode plates 20a,
It is formed so as to correspond to the circumferential length of 20b. still,
In this case, the reinforcing portion 24a of the coverlay 24 in the above-mentioned embodiment is unnecessary. Even in this case, the same effects as the effects (1) to (3) and (6) of the above-described embodiment can be obtained.

In the above embodiment, the comb-teeth-shaped contact portion 2 is used.
5c and 26c are, as shown in FIG.
Although it is formed so as to extend to the outside of the middle circle between the inner circumference and the outer circumference of a, the comb-teeth shaped contact portions 25c and 26c may be formed inside the middle circle. With this configuration, the comb tooth connecting portions 25d and 26d and the comb tooth-shaped contact portions 25c and 26c are formed.
Suppressing strong vibration, which is vibration generated outside the piezoelectric element 12 in the radial direction, is further reduced.

In the above embodiment, the comb-teeth-shaped contact portion 27c formed on the feedback conductor 27 is formed so as to extend radially inward as shown in FIG.
The comb-teeth connecting portion connecting the comb-teeth-shaped contact portions may be arranged inside in the radial direction, and the comb-teeth-shaped contact portion 27c may be formed so as to extend outward in the radial direction. By doing so, it is possible to reduce that the comb-teeth connecting portion suppresses strong vibration, which is vibration generated outside the piezoelectric element 12 in the radial direction.

In the above embodiment, the traveling wave type ultrasonic motor is embodied, but the standing wave type ultrasonic motor may be embodied. In this case, the polarization pattern of the piezoelectric element 12 and the pattern of the electrode plate are changed, and the conductor 2
It is also necessary to change the position of 3 and so on.

Next, technical ideas other than the claims that can be understood from the above-described embodiments will be described below together with their effects. ○ In the wiring structure of the ultrasonic motor according to claim 1,
The wiring structure of the ultrasonic motor, wherein the electrode plate (20) to which the conductor (23) is fixed is a feedback electrode plate (20f). In this way, the conductor 23 fixed to the feedback electrode plate 20f is suppressed from suppressing the vibration of the piezoelectric element 12.

[0057]

As described in detail above, according to the present invention,
It is possible to provide a wiring structure for an ultrasonic motor that can suppress the vibration of the piezoelectric element and improve the maximum output of the ultrasonic motor.

[Brief description of drawings]

FIG. 1 is an explanatory diagram illustrating an ultrasonic motor according to an embodiment.

FIG. 2 is an exploded perspective view for explaining the flexible substrate according to the present embodiment.

FIG. 3 is a top view for explaining the flexible substrate of this embodiment.

FIG. 4 is an explanatory diagram for explaining a conductor according to the present embodiment.

FIG. 5 is an explanatory diagram for explaining a coverlay according to the present embodiment.

FIG. 6 is a top view for explaining a flexible substrate of another example.

[Explanation of symbols]

10 ... Stator, 12 ... Piezoelectric element, 16 ... Rotor, 20
... Electrode plates 21, 31 ... Flexible substrates, 23, 3
2, 33 ... Conductors, 20a, 20b ... First and second electrode plates, 25a, 26a ... Conductor tips, 25c, 26c,
32b, 33b ... Comb-shaped contact portions, 25d, 26d, 3
2a, 33a ... Comb-tooth connecting portion.

Continuation of the front page (56) Reference JP-A-63-64581 (JP, A) JP-A-6-54556 (JP, A) JP-A-6-90574 (JP, A) JP-A-3-164079 (JP , A) JP 59-204476 (JP, A) JP 60-210175 (JP, A) JP 60-210177 (JP, A) JP-B 7-44850 (JP, B2) (58) Fields investigated (Int.Cl. ⁷ , DB name) H02N 2/00 H01L 41/09

Claims (6)

(57) [Claims] 1. A predetermined electrode plate (20) is fixed to a ring-shaped piezoelectric element (12) provided on a stator (10) and which generates vibration for rotating a rotor (16), and the electrode plate (20) is fixed. 20) The flexible substrate (21, 31) is fixed to the flexible substrate (21, 31), and the piezoelectric element (12) is formed by the conductors (23, 32, 33) provided on the flexible substrate (21, 31).
In the wiring structure of the ultrasonic motor for electrically wiring with respect to the above, the portions (25a, 26a) of the conductors (23, 32, 33) fixed to the electrode plate (20) are the piezoelectric elements.
It is formed inside the middle circle between the inner circumference and the outer circumference of (12).
Together with the comb tooth connecting portions (25d, 26d, 32a, 33a) extending in the circumferential direction of the piezoelectric element (12), and the piezoelectric element (12) radial direction from the comb tooth connecting portions (25d, 26d, 32a, 33a). Comb-shaped contact portions (25c, 26c, 32b, 33) that extend to the outside of the body and are divided into a plurality of pieces in the circumferential direction.
b) The wiring structure of the ultrasonic motor, characterized in that 2. The wiring structure for an ultrasonic motor according to claim 1, wherein the electrode plate (2) to which the conductors (23, 32, 33) are fixedly attached.
The wiring structure of the ultrasonic motor is characterized in that 0) is a driving electrode plate (20a, 20b). 3. The wiring structure for an ultrasonic motor according to claim 1, wherein the comb tooth connecting portions (25d, 26d, 32a, 33a) are provided.
Is formed inside an intermediate circle between the inner circumference and the outer circumference of the piezoelectric element (12). 4. The wiring structure for the ultrasonic motor according to claim 1, wherein the comb tooth connecting portions (25d, 26d, 32a, 33a) and the comb tooth-shaped contact portions (25c, 26c, 32b, 33
A wiring structure of an ultrasonic motor, wherein b) is formed inside an intermediate circle between the inner circumference and the outer circumference of the piezoelectric element (12). 5. The wiring structure for an ultrasonic motor according to claim 1, wherein the comb tooth connecting portions (25d, 26d) and the comb tooth shaped contact portions (25c, 26c) are provided. A wiring structure for an ultrasonic motor, wherein the wiring structure is formed so as to come into contact with a part of the electrode plates (20a, 20b) extending in a circumferential direction with a predetermined length. 6. A piezoelectric element (12) fixed to a predetermined electrode plate (20) fixed to an annular piezoelectric element (12), and the piezoelectric element (23, 32, 33) provided on the fixed surface. In the annular flexible substrate for piezoelectric element electrically connected to the piezoelectric element 12), the portions (25a, 26a) of the conductors (23, 32, 33) fixed to the electrode plate (20) are the piezoelectric element.
It is formed inside the middle circle between the inner circumference and the outer circumference of (12).
Together with the comb tooth connecting portions (25d, 26d, 32a, 33a) extending in the circumferential direction of the piezoelectric element (12), and the piezoelectric element (12) radial direction from the comb tooth connecting portions (25d, 26d, 32a, 33a). Comb-shaped contact portions (25c, 26c, 32b, 33) that extend to the outside of the body and are divided into a plurality in the circumferential direction
b) An annular flexible substrate for a piezoelectric element, comprising: