JPH03203574A - Oscillatory wave motor - Google Patents

Abstract

PURPOSE:To secure the electric conductivity by making a face for junction with the vibration elastic body of an electrical-mechanical energy conversion element rougher than the junction face of the vibration elastic body. CONSTITUTION:The surface of a copper layer 11 laminated on a nickel layer on a face for junction with the vibration elastic body 7 of an electrostrictive element 10 is made rougher than the junction face of the vibration elastic body 7. A proper quantity of bond dropped at one or more points on the junction face of the vibration elastic body 7 flows evenly into the gaps in the copper layer 11 of the electrostrictive element 10 instead of direct compression bonding of the vibration elastic body 7 to the electrostrictive element 10, forming a uniform bond layer on the whole face without overflow of the bond. Thereby strong bonding is made possible, the copper layer 11 comes into direct contact with the vibration elastic body 7, and the electric conductivity is securely obtained.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a vibration wave motor.

[Prior Art] The general structure of a vibration wave motor is that an electromechanical energy conversion element (hereinafter abbreviated as element) such as an electrostrictive element or a piezoelectric element is mounted on one surface of a metallic vibrating elastic body formed in the shape of an annular ring. ) is glued with adhesive and used as a vibrator, and by applying an AC voltage to the element, two standing waves with a positional phase shift of 90 degrees are excited in the vibrating elastic body, and these standing waves are The rigidity of the wave forms a traveling wave at a wavelength ahead, and the traveling wave frictionally drives a moving body that is pressed against the surface opposite to the adhesive surface of the element. The element is generally formed in a ring shape that matches the external shape of the vibrating elastic body, and the two driving phases for forming a standing wave are formed with a positional shift of, for example, 4/4. In addition, in each drive phase, element sections with alternating polarization directions are formed with a positional shift of 1/2, and these drive phases are temporally separated by 90°.
An alternating current voltage having a phase difference of degrees is applied.

FIG. 6 shows a sectional view of a vibration wave motor having such a configuration. l is a vibrating elastic body, on the upper surface of which a large number of slits S are formed in the circumferential direction in order to lower the neutral axis of vibration, and the protrusions between the slits are in pressure contact with a rotor (not shown) via a friction member, and these protrusions The rotor is driven to rotate by the traveling waves formed above. The vibrating elastic body l is
For example, the base material is an iron alloy such as austenitic stainless steel, and is coated with an ultra-hard layer 2 of, for example, a nickel phosphorus alloy containing silicon carbide by plating. After the plating process, the ultra-hard layer 2 is machined on the adhesive side of the element 3 until the bare surface is exposed.

In the element 3, a current-carrying electrode is formed for each element section on one side, and a GND electrode is provided on the other side, and the vibrating elastic body l is used as a grounding electrode on the GND electrode side. is aligned with the vibrating elastic body 1 and bonded with an adhesive 5. In addition, each current-carrying electrode of the element 3, especially the electrodes of each section forming the A phase and B phase for driving, is formed by an electrode layer 6 formed by coating an electrode agent made of silver powder, etc., as shown in FIG. The electrode layers 6 connected to each other and connecting the drive A phase and B phase are connected to an external circuit such as a drive circuit via a flexible printed wiring board (hereinafter abbreviated as flexible) 4. The flexible board 4 is bonded to the element 3 with an adhesive 5.

[Problems to be Solved by the Invention] However, conventional vibration wave motors have the following problems.

(1) Invar, which is a soft cutting material, is used as the material for the vibrating elastic body even though it is a ferrous alloy material, so it is expensive to perform processing such as grooving to form slits, and the parity after grooving is high. Because of this, it may not be possible to remove all of it in the subsequent deburring process, and in the next process of forming the ultra-hard layer 2, uneven thickness and uneven coating of the ultra-hard layer 2 may occur depending on the location of the vibrating elastic body. was there.

(2) When joining the vibrating elastic body 1 and the element 3, the adhesive 5 was applied using a squeegee using a screen printing method. If the adhesive sticks out, the pattern width of the screen plate must be adjusted to adjust the amount of adhesive applied, but this requires replacing the entire screen plate.

(3) Since the adhesive for bonding the element 3 and the flexible plate 4 was applied using a screen printing method, the adhesion strength varied depending on the sample as in the above case.
If the adhesion is weak, there is a risk of peeling between the element 3 and the flexible plate 4, and when a voltage is applied to the element 3 and the element is driven, the part where the peeling occurs will vibrate and make an abnormal noise. Occasionally this occurred.

In addition, such bonding methods require an adhesive coating process and are cumbersome, making them unsuitable for mass production.

(4) Since a two-component adhesive is used as the adhesive,
The viscosity changes during the time from when the two liquids are stirred until the actual application starts, and if it takes time to replace the screen plate mentioned above, the viscosity change will be exacerbated, and the squeegee Depending on the pressing force and printing speed, the amount of adhesive may vary from sample to sample, or even from place to place within the same sample, and there have been cases where sufficient electrical conduction between the element 3 and the vibrating elastic body l cannot be achieved.

(5) If air bubbles appear before stirring the two-component adhesive,
Alternatively, when using an adhesive in which the amount of the two liquids to be stirred is large and sufficient stirring cannot be performed, there is a drawback that the adhesion is not stable if the amount of adhesive applied is small.

(6-) Conventionally, Dotite D500 (trade name) was used as the electrode material for the electrode layer 6 and was spray-coated, but since this electrode material was not originally a spray type, it clogged the roots of the spray nozzle. The coating amount tends to vary widely, and over time, the metals contained may precipitate, resulting in variations in properties. Furthermore, it requires troublesome work such as masking during coating.

The purpose of the present invention is to solve such conventional problems, improve the adhesion between an electro-mechanical energy conversion element such as an electrostrictive element, a vibratory elastic body, and a flexible printed wiring board, and It is possible to ensure electrical continuity for each, and it can be made suitable for mass production. Furthermore, it is possible to use inexpensive materials that can reduce the occurrence of cracks during processing without deteriorating the characteristics as a vibrating body. It is an object of the present invention to provide a vibration wave motor which can be used as a base and which can reduce costs as a whole.

[Means and operations for solving the problem] The gist of the present invention to achieve the object is to connect one side of the electro-mechanical energy conversion element to a vibrating elastic body using an adhesive as a grounding electrode. At the same time, the electrodes of each section on the other side of the element are connected via a flexible printed wiring board, and the flexible printed wiring board and the other side of the element are bonded together using an adhesive. In the vibration wave motor, the surface roughness of the joint surface of the electro-mechanical energy conversion element with the vibration elastic body is formed to be rougher than the surface roughness of the joint surface of the vibration elastic body, and The vibration wave motor is characterized in that it is connected to the electrode of the electro-mechanical energy conversion element via a convex electrode.

In the vibration wave motor having the above configuration, the contact surface of the electro-mechanical energy conversion element with the vibrating elastic body is made rougher than the contact surface on the vibrating elastic body side, so that the rough bonding surface of the electro-mechanical energy conversion element can be seen on a microscopic scale. When observed visually, there is a mixture of parts with adhesive applied and parts with protrusions that are not, and these countless protrusions come into contact with the smooth joint surface of the vibrating elastic body, and the adhesive force is reduced. This means that sufficient and reliable electrical continuity can be obtained.

In addition, since electrical continuity is obtained between the electro-mechanical energy conversion element and the flexible printed wiring board through a convex electrode, such as an anisotropic conductive sheet, it is necessary to If an adhesive made of resin is applied, the flexible printed wiring board can be bonded to the electro-mechanical energy conversion element simply by aligning the flexible printed wiring board with the specified position of the electro-mechanical energy conversion element and then heating it. be able to.

On the other hand, the vibrating elastic body is made of iron alloy such as brass or non-austenitic stainless steel, and is made of tungsten carbide, boron carbide, titanium carbide, silicon carbide, molybdenum carbide, molybdenum boron, chromium carbide, titanium nitride, etc.
By being coated with a superhard material made of a nickel phosphorous alloy containing at least one of hard elements such as tungsten silicon, boron nitride, aluminum oxide, and boron sulfite, the vibration characteristics of a vibration wave motor are improved compared to those of conventional vibration wave motors. Furthermore, the thermal expansion is almost the same as that of the electro-mechanical energy conversion element, and sufficient hardness can be obtained, and the occurrence of burr during cutting can be reduced.

As a hard element, if it has a hardness of 100 HV or more, it can withstand use, and for carbide materials, it is desirable that the hardness is 100 OHV or more, and if the film thickness is about 1 μm or more, it has excellent durability. If not required, the film thickness is 1μm.
The following is also sufficient.

The base material and the carbide material covering the base have sufficient hardness even when used in a member that is pressed against a vibrating elastic body and moves relative to the vibrating elastic body, so the efficiency of the motor is improved. will not deteriorate.

[Example] The present invention will be described in detail below based on an example shown in the drawings.

Embodiment 1 FIGS. 1 to 4 show Embodiment 1 of the vibration wave motor according to the present invention, in which FIG. 1 is a cross-sectional view of a vibrator, FIG. 2 is a plan view of its bottom side, and FIG. FIG. 4 is an enlarged cross-sectional view of the joint between the elastic body and the electrostrictive element, and FIG. 4 is an enlarged cross-sectional view of the joint between the electrostrictive element and the flexible printed wiring board. The illustrations are exaggerated to facilitate understanding of the embodiment.

The vibrating elastic body 7 of this embodiment is formed in the same shape as the conventional vibrating elastic body shown in FIG. 6, but the base metal material is non-austenitic stainless steel (5
tlS420J) is used, and the ultra-hard layer 2 made of a nickel-phosphorus alloy that coats the base is made of a nickel-phosphorus alloy containing silicon carbide (KN-3iC), and the ultra-hard layer 2 is formed using the following method. It is formed.

It is formed by immersing the base metal in an electroless solution in which silicon carbide is dispersed in a plating solution, and eutectoidizing it as a plating film on the surface of the base metal, to a thickness of, for example, 50 μm. The content of silicon carbide in this case was 15% by volume.

The ultra-hard layer 2 coated on the base by the electroless plating method naturally also covers the joint surface with the electrostrictive element IO, so that joint surface is ground down until the base is exposed. In this embodiment, the electrostrictive element 10 which is the exposed surface of this base body
The surface to be bonded with is processed to have a surface roughness of approximately 0.5S.

On the other hand, the electrostrictive element 10 has a nickel layer on the joint surface side with the vibrating elastic body 7 in order to have good adhesion with the adhesive.
A copper layer 11 is laminated, and the surface roughness of the copper layer 11 is rougher than that of the bonding surface of the vibrating elastic body 7.

Therefore, as shown in FIG. 3, in a state where the vibrating elastic body 7 and the electrostrictive element 10 are joined, countless gaps are formed on the joining surface on the electrostrictive element 10 side.

The adhesive can be applied by dropping an appropriate amount of the adhesive 5 on the bonding surface of the vibrating elastic body 7 at several locations or at several locations, and directly applying the adhesive to the electrostrictive element IO without using the conventional screen printing method. If the adhesive is pressed against the copper layer 11 of the electrostrictive element 10, it will flow evenly into the gap between the copper layers 11 of the electrostrictive element 10, and a -like adhesive layer will be formed on the entire surface without the adhesive leaking out, thereby providing strong adhesive force. The copper layer 11 between the gaps is directly connected to the vibrating elastic body 7
Electrical continuity is ensured by making contact with the

On the other hand, electrodes of the divided element are formed on the other surface of the electrostrictive element 10, and as shown in FIG. 2, each electrode of the A phase 13 and each electrode of the B phase 14 for driving is Electrical continuity is established by the electrode cotton layer 9, respectively. This electrode cotton layer 9
is used in the form of a paste, and is applied directly with a dispenser, for example. As a paste, gold,
Metal powders such as silver are difficult to precipitate or separate, require a long hot time such as hard to harden at room temperature, and have a relatively low viscosity during application. For example, Silvest P2
There is 46 (product name).

As shown in FIG. 4, an anisotropic conductive sheet 8 having a convex pole portion 15 is attached to the pattern surface side of the flexible substrate 4 in advance in a manner corresponding to the bonding portion with the electrode 16, 17 of the electrostrictive element IO. Furthermore, a heat-melting adhesive is provided around the convex pole portion 15 in advance.

The flexible plate 4 and the convex pole part 15 of the anisotropic conductive sheet 8 are fixed to each other so as to obtain electrical continuity. Therefore, simply aligning the flexible plate 4 with the predetermined position of the electrostrictive element 1O and then heating it is enough. The flexible plate 4 can be bonded to the electrostrictive element IO.

The thickness of the ultra-hard layer 2 of the vibratory elastic body 7 may be 1 μm or more, but in order to obtain the best characteristics especially as a vibration wave motor, the thickness of the ultra-hard layer 2 of the vibrating elastic body 7 should be 10 to 100 μm on the contact surface with the moving body.
It is sufficient that the film thickness is approximately 1 μm, and for other parts, the film thickness is approximately 1 μm or more, considering the electroless plating process.
It is desirable that the film thickness be approximately the same as that of the contact surface. Further, the content of the hard element at this time may be 1% by volume or more, but in consideration of the precipitation ability of the hard element and the durability of the vibrating elastic body, it is preferably 1 to 30% by volume.

Further, it is desirable that the surface roughness of the joint surface of the vibrating elastic body 7 with the electrostrictive element 10 is 1 s or less.

This means that the surface roughness of the copper film 11 of the electrostrictive element IO is 1 to 8 μm.
Therefore, if the surface roughness of the joint surface of the vibrating elastic body 7 becomes 1S or more, there is a possibility that the adhesion force becomes uneven.

The nickel and copper films laminated on the electrostrictive element 10 may have a thickness of about 0.05 μm or more, but in consideration of the film formation process, the above-mentioned film thickness is preferable.

Embodiment 2 FIG. 5 is a sectional view showing Embodiment 2 of the vibration wave motor according to the present invention.

In Example 1 described above, the ultra-hard layer 2 at the bottom of the vibrating elastic body 7 was ground down until the base was exposed, but in this example, the electrostrictive element lO is glued together.

In this case, in order to ensure the bonding strength with the electrostrictive element IO, it is desirable that the content of hard elements in the superhard material deposited at the bottom of the vibrating elastic body 7 is 10% by volume or less.

Note that the flexible substrate 4 and the electrostrictive element 10 are joined in the same manner as in the first embodiment.

[Effects of the Invention] As explained above, according to the present invention, adhesion between a vibrating elastic body and an electro-mechanical energy conversion element such as an electrostrictive element using an adhesive can prevent the adhesive from extruding. It can be done without any problems, and the electrical connections can be made reliably, and the adhesive can be applied without using the traditional screen printing method.
It is suitable for mass production because it only needs to be applied in one or a few spots using a dispenser.

Furthermore, since the electrical-mechanical energy conversion element and the flexible printed wiring board are connected via a convex electrode, such as an anisotropic conductive sheet, for example, an adhesive may be applied in advance around the convex electrode. If the flexible printed wiring board is placed in the predetermined position of the electric-mechanical energy converting means, it becomes possible to bond the board.In particular, by using a heat-melting adhesive, the bonding process becomes easier and mass production becomes easier. Coupled with the adhesive structure that has suitable effects and facilitates mass production between the electro-mechanical energy conversion element and the vibrating elastic body, it becomes possible to dramatically mass-produce vibration wave motors.

Furthermore, by using non-austenitic stainless steel as the material for the vibrating elastic body, for example, it can be provided at a low cost without impairing the vibration characteristics, and it is also possible to form an ultra-hard layer similar to conventional ones. The required hardness can also be fully satisfied.

[Brief explanation of drawings]

Fig. 1 is a sectional view showing Embodiment 1 of the vibration wave motor according to the present invention, Fig. 2 is a plan view of the back side thereof, Figs. 3 and 4 are enlarged sectional views of main parts, and Fig. 5 is an implementation example. Cross-sectional view of Example 2, No. 6
The figure is a sectional view of a conventional vibration wave motor, and FIG. 7 is a plan view of the back side thereof. 1, 7: Vibratory elastic body 2: Ultra-hard layer 1O13: Electrostrictive element 4: Flexible printed wiring board 5: Adhesive 6.9: Electrode layer 8: Anisotropic conductive sheet 11: Copper layer 13: A phase 14 : B phase 15: Convex electrode 16.17: Electrode.

Claims (1)

[Claims] 1. One side of the electro-mechanical energy conversion element is bonded to a vibrating elastic body as a grounding electrode via an adhesive, and the electrodes of each section on the other side of the element are flexible printed. A vibrating wave motor having a vibrator connected via a wiring board and having the flexible printed wiring board and the other side of the element bonded via an adhesive, wherein the vibrating elastic body of the electro-mechanical energy conversion element The flexible printed wiring board and the electrode of the electro-mechanical energy conversion element are connected via a convex electrode. A vibration wave motor characterized by: 2. The vibration wave motor according to claim 1, wherein the vibrating elastic body is made of brass or an iron alloy such as non-austenitic stainless steel. 3. The vibrating elastic body is made of at least one of hard elements such as tungsten carbide, boron carbide, titanium carbide, silicon carbide, molybdenum carbide, molybdenum boron, chromium carbide, titanium nitride, tungsten silicon, boron nitride, aluminum oxide, and boron sulfite. The vibration wave motor according to claim 2, characterized in that the vibration wave motor is coated with a superhard material made of a nickel phosphorus alloy containing one or more types of nickel phosphorus alloy. 4. The vibration wave motor according to claim 3, wherein the ultrahard material covering the base of the vibratory elastic body has a total content of at least one type of hard element of 1 to 30% by volume. 5. The vibration wave motor according to claim 1 or 2, wherein a copper layer is provided on the surface of the electro-mechanical energy conversion element that is to be bonded to the vibration elastic body. 6. Claims 2 and 3, characterized in that the joint surface of the vibrating elastic body with the electro-mechanical energy conversion element is its base body.
, 4 or 5. The vibration wave motor according to . 7. Claim 2, characterized in that the joint surface of the vibroelastic body with the electro-mechanical energy conversion element is an ultra-hard layer thereof.
, 3, 4 or 5. 8. The vibration according to claim 1, 2, 3, 4, 5, 6 or 7, wherein the surface roughness of the joint surface of the vibrating elastic body with the electro-mechanical energy conversion element is 1 s or less. wave motor. 9. Claim 1, 2, 3, 4, 5, 6, 7, or 8, characterized in that the surface roughness of the joint surface of the electro-mechanical energy conversion element with the vibrating elastic body is 1 to 8 s. The vibration wave motor described in . 10. Claims 1, 2, and 3, wherein the convex electrode that connects the flexible printed wiring board and the electro-mechanical energy conversion element is an anisotropic conductive sheet.
, 4, 5, 6, 7, 8 or 9. 11. The vibration wave motor according to claim 11, wherein the anisotropic conductive sheet is provided with a heat-melting adhesive around the electrodes and is attached to the flexible printed wiring board.