JPH0767361A - Stator of electrostatic actuator and its manufacture - Google Patents

Abstract

PURPOSE:To obtain a stator not requiring the widening of the facing distance between electrodes by embedding, in the form of flush with the top surface of an adhesive layer, part of an electrode pattern and a feed line pattern provided on the top surface of an insulation substrate and then covering the top surface with an insulation layer. CONSTITUTION:An insulation substrate 5 as the main body portion of a stator A is produced by blending a thermoplastic high-viscosity saturated polyester resin, glass fiber and inorganic filler and then by extrusion molding, and copper foil is adhered to the top surface through an adhesive layer 7 by heating and pressing means. Then, copper foil is subjected to electrodeposition resist treatment thereby forming a resist pattern corresponding to feed line patterns 2A and 3A, and unnecessary portion of the copper foil is removed by etching treatment and a required conductor pattern P is formed on an adhesive layer 7. Then, flattening treatment is given to make the top surface of the projected conductor pattern p flush with the top surface of the adhesive layer 7. In consequence, a gap between electrodes C2 be made sufficiently close each other and smooth driving is guaranteed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stator for an electrostatic actuator and an improvement in a method for manufacturing the stator.

[0002]

2. Description of the Related Art A schematic structure of a conventional electrostatic actuator and its operation will be described with reference to FIGS. As shown in FIG. 9, the electrostatic actuator 300 is in contact with the upper surface of the thin plate-shaped stator 101, and the thin plate-shaped movable element 20 is also provided.
1 is provided so as to be movable in parallel with the stator 101 in a predetermined direction. Stator 101 and mover 2
01 indicates the insulating substrate 101a as shown in FIGS.
And 201a as the main body, and dielectric layers 102 and 2 made of polyurethane resin or the like on the opposing surfaces of both insulating substrates.
02 are laminated. The dielectric layers 102 and 2
02, a plurality of rows of lower electrodes 103 and upper electrodes 203 each having a strip shape are embedded in parallel at predetermined intervals. Then, each set of three lower electrodes 10 adjacent to each other
Each phase voltage supplied from the three-phase power supply (500 to 1000 V) is supplied to the circuit 3 via the drive control circuit (not shown) and the power supply circuit 104. As another embedding method for the lower electrode 103, as shown in FIG. 12, an extremely thin lower electrode 103 is patterned on an insulating substrate 101a using an ultrathin metal foil or the like, and an insulating film is formed on the upper surface thereof. A method of attaching 105 is also performed. Regarding the operating principle of the electrostatic actuator having the above-mentioned structure, see "JP-A-3-65081" and "JP-A-5-91."
761 "and the like. The outline is the stator 10
When a three-phase voltage is applied to the lower electrode 103 of No. 1, electric charges are induced in the upper electrode 203 of the mover 201. In this state, if the polarity of the voltage applied to each phase of the lower electrode 103 is changed in a predetermined pattern by the drive control circuit, the charge distribution on the stator 101 side immediately changes, but the mover 20
The charge induced on the 1st side is delayed by the resistance of the upper electrode 203 and delayed. For this reason, on the stator 101 side and the mover 201 side, the electrodes 103 and 203 facing each other are in the state of being charged with the same polarity, and the mover 20
1 is levitated on the stator 101 due to the repulsive force generated between the same poles, and the mover 201 has different polarities generated on the upper and lower counter electrodes due to the delayed movement of the induced charges generated in the upper electrode 203. By the electrostatic attraction force between them, the lower electrodes 103 are moved in the parallel direction by one pitch. The moving speed, moving distance, and moving direction are arbitrarily controlled by the drive control circuit.

[0003]

By the way, the lower electrode 1
When 03 is embedded by the method shown in FIG. 11, the inter-electrode portion b where the lower electrode 103 does not exist becomes considerably thicker than the electrode embedded portion c as shown in the figure. Therefore, when the lower electrode 103 is coated with the synthetic resin dielectric layer 102 by a coating means or the like, the degree of volume contraction due to the solidification of the dielectric layer is large in the inter-electrode portion b, which is so-called " Due to the sink mark phenomenon, the recessed portion d is formed. Therefore, when a high voltage of 500 to 1000 V (current density is extremely small) is applied to the lower electrode 103, dielectric breakdown may occur near the recessed portion d. In order to eliminate this danger, it was necessary to make the dielectric layer 102 considerably thick in consideration of the safety factor against dielectric breakdown. Dielectric layer 102
If the thickness of the upper and lower electrodes 103, 20
The gap between the three spreads, the driving force of the electrostatic actuator decreases, and the thickness of the stator 101 increases. Further, according to the method of forming the dielectric layer 102 by a coating means or the like, it is difficult to make the coating thickness uniform, so that it becomes difficult to keep the air gaps evenly over the entire surface of the stator 101. There was also a problem that it was difficult to obtain a smooth driving force. On the other hand, when the lower electrode 103 is insulatingly coated by the method shown in FIG. 12, the insulating film 105 has a much finer structure and excellent insulating performance as compared with the resin coating layer, and has a uniform thickness. So
A thin insulating film 105 can be used to significantly narrow the air gap. However, the adjacent lower electrodes 103, 1
Since the gap between 03 is as narrow as 100 μm inside and outside, even if vacuum suction is performed when the insulating film 10 is applied, it is difficult to avoid the phenomenon that the gap g is left at the stepped portion on both ends of the lower electrode 103. . Then, in order to compensate for the decrease in dielectric strength due to the presence of the gap g, the facing interval (pitch) of the parallel lower electrodes 103 has to be widened. Therefore, the object of the present invention is to minimize the facing distance between the electrodes formed on the stator and the mover, and to widen the facing distance between the parallel electrodes in order to secure the necessary dielectric strength. Another object of the present invention is to provide a stator of an electrostatic actuator and a method for manufacturing the same, which are designed to be completed.

[0004]

To achieve the above object, a stator of an electrostatic actuator according to the present invention comprises a stator having a plurality of electrode patterns arranged in parallel on an insulating substrate, and the stator. A movable element arranged so as to be able to move in parallel with the movable element, and the electrode is applied to the stator by an electrostatic force generated between the movable element and the stator by applying a voltage of a polyphase power source to the electrode pattern. In the case of moving in a pattern parallel direction, the stator includes electrode patterns 1 to 3 provided on an upper surface of an insulating substrate 5 via an adhesive layer 7 and power supply path patterns 1A to 1A to the electrodes. At least a part of 3A is embedded in the adhesive layer 7 so as to be flush with the upper surface of the adhesive layer 7, and the upper surface is covered with insulating layers 9 and 9A. Then, the insulating layer 9A may be formed of a synthetic resin film. Further, in the method for manufacturing the stator of the electrostatic actuator according to the present invention, the insulating substrate 5 is made of a synthetic resin having a property of being crystallized by heating, and the upper surface of the insulating substrate 5 before being crystallized is Electrode patterns 1 to 3 and its power feeding path pattern 1A through the adhesive layer 7 which is thermosetting and is in a semi-cured state.
3A (conductor pattern P) is formed, and the insulating substrate 5 on which the conductor pattern P is formed is subjected to heat / pressure press treatment so that the conductor pattern P is flush-filled in the adhesive layer 7. At the same time, the insulating substrate 5 is changed to a crystal structure,
And a flattening treatment step for completely curing the adhesive layer 7,
An insulating step of covering the flattened conductor pattern P with the insulating layers 9 and 9A is preferably included. Then, of the electrode patterns 1 to 3 and the power feeding path patterns 1A to 3A, other conductor patterns P except the power feeding path pattern 1A are embedded in the adhesive layer 7, and the upper surface thereof is covered with the insulating layer 9. Next, the power supply path pattern 1A is formed on the upper surface of the insulating layer 9, and the power supply path pattern 1A is electrically connected to the conduction spot 4 provided on the electrode pattern 1, and then the power supply path pattern 1A and the conduction spot 4 are connected to each other. It is preferable to cover with the insulating layer 10. In addition, of the second insulating layer 10, the insulating layer 10 covering the formation regions of the electrode patterns 1 to 3 is
It may be formed of a synthetic resin film.

[0005]

The electrode patterns 1 to 3 to be formed on the upper surface of the insulating substrate 5 forming the main body of the stator and the feeding path patterns 1A to 1A to
By embedding at least a part of 3A in the adhesive layer 7 provided on the upper surface of the insulating substrate 5 so that their upper surfaces are flush with the upper surface of the adhesive layer 7, The thickness of the insulating layers 9 and 9 </ b> A for covering the layer is thinner than the conventional one and is sufficient. The insulating layer 9A is made of a synthetic resin film having excellent electrical insulation properties, a dense structure, and an extremely uniform thickness.
By forming the above, a thinner insulating layer will be sufficient. Therefore, the gap between the electrodes provided on each of the stator and the mover can be narrowed by that amount, and the driving performance of the electrostatic actuator can be improved correspondingly, and the thickness can be reduced. Further, by adopting a method of embedding the electrode patterns 1 to 3 and the power feeding path patterns 1A to 3A in the adhesive layer 7, it is possible to greatly reduce the labor and time required for manufacturing the electrostatic actuator. Further, by using a synthetic resin having a property of crystallizing by heating to lose flexibility and increase rigidity as a material of the insulating substrate 5, the above-mentioned embedding treatment of the electrode patterns 1 to 3 and the power feeding path patterns 1A to 3A is easy. In addition, the stator can be formed in any shape.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. The basic configuration of the electrostatic actuator of this embodiment is substantially the same as the conventional one shown in FIGS. 9 and 10, but the configuration of the stator A is essentially different from the conventional one. The detailed structure of the stator A is shown in FIG. 1 as a partial plan perspective view thereof, and FIG. 2 is a vertical cross section taken along line XX of FIG. 1, and is shown as a vertical cross section taken along line YY of FIG. 3 and FIG. 4, which shows a vertical section taken along line ZZ of FIG. 1, and FIG. 5 which shows a manufacturing process, will be sequentially described.

In FIG. 1, a mover B mounted on a portion sandwiched by two parallel two-dot chain lines a, drawn on the central portion of the stator A, is guided by a movement guide means (not shown). It is possible to move in the left-right direction in the figure. In the central portion, electrode patterns 1 to 3 to which the voltages of the respective phases of S, R and T of the three-phase power source are respectively supplied are formed on the same plane by a comb tooth-shaped pattern as shown in the drawing. There is.

Reference numerals 1A to 3A are power supply path patterns of the electrode patterns 1 to 3 and are formed on the same plane integrally with the electrode patterns 1 to 3. However, power supply line pattern 1
As shown in FIG. 3, only A is formed on the upper surface of the electrode patterns 1 to 3 and the power feeding path patterns 1A to 3A via an insulating layer 9 described later that insulates the electrodes. The respective base ends of the respective power feeding path patterns 1A to 3A have power feeding terminals R of the respective phases,
It is S and T. In addition, the electrode pattern 1 has a conductive spot 4 surrounded by a small dashed circle in FIG.
It is electrically connected to the power feeding path pattern 1A.

The insulating substrate 5 (see FIGS. 2 and 3), which is the main body of the stator A, uses a synthetic resin plate "Unilate" developed by Unitika Ltd. in this embodiment. This "Unilate" is a highly viscous thermoplastic polyester resin that has the property of changing from an amorphous structure to a crystalline structure when heated above its crystallization temperature. It is made by. The plate thickness in this case is 0.3 to 2.0 mm.

Next, the procedure for patterning the electrode patterns 1 and the feeding path patterns 1A to 3A on the upper surface of the insulating substrate 5 will be sequentially described below. 6 is a flowchart showing the manufacturing process of the stator A of this embodiment. First, as shown in FIG. 5A, the copper foil 6 is attached to the upper surface of the insulating substrate 5 by the heat / pressure pressing means via the thermosetting synthetic resin adhesive layer 7. To do this, the copper foil 6 having the adhesive layer 7 previously formed on the back surface by a coating means or the like is rolled to a pressure of 10 Kgf.
/ Cm, thermocompression-bonding on conditions of 130-150 degreeC.
Alternatively, the adhesive layer 7 formed in a film shape is used as the insulating substrate 5.
It may be interposed between the copper foil 6 and the copper foil 6 and subjected to heat / pressure press treatment. The adhesive layer 7 is thicker than the copper foil 6.

Next, the copper foil 6 is subjected to an electrodeposition resist treatment to form electrode patterns 1 to 3 and power supply path patterns 2A and 3A (hereinafter, these patterns are collectively referred to as a conductor pattern P). A corresponding resist pattern is formed.
Then, an etching process is performed to chemically remove the unnecessary portion of the copper foil 6, so that the required conductor pattern P is formed on the adhesive layer 7, as shown in FIG. That is,
The copper foil 6 can be changed to the form of the conductor pattern P. In this state, the conductor pattern P projects on the upper surface of the adhesive layer 7 by the thickness thereof, in this case, 10 to 50 μm.

Therefore, this protruding conductor pattern P
Is embedded in the adhesive layer 7 such that the upper surface thereof is flush with the upper surface of the adhesive layer 7. To do this, as described in FIG. 5 (c),
The heat / pressure press treatment may be performed using a press device or the like. Reference numeral 8 in the figure is a pair of upper and lower mirror plates made of stainless steel as a press die, and a release film made of fluororesin or the like is provided on the press surface. The insulating substrate 5 having the conductor pattern P formed on the upper surface thereof via the adhesive layer 7 is sandwiched between the mirror surface plates 8 and 8 to crystallize the above-mentioned thermoplastic saturated polyester resin constituting the insulating substrate 5. 1 required
While heating at 80 to 190 ° C., a pressure condition of 50 Kgf / cm is maintained for about 30 minutes.

During this time, the conductor pattern P is completely embedded in the gelled adhesive layer 7 during heating, and
The thermoplastic saturated polyester resin changes from an amorphous structure to a crystalline structure, and the mechanical and electrical characteristics of the insulating substrate 5 are significantly improved. Then, the adhesive layer 7 is also completely cured.
Note that, during the progress of this heat / pressure press treatment, the insulating substrate 5 which is still plastic before crystallization deforms so as to provide a relief for the adhesive layer 7 pressed by the conductor pattern P. Therefore, the conductor pattern P can be embedded smoothly without any problem.

After the flattening process is completed, the insulating substrate 5 which is cooled and taken out from the press machine is then connected to the power supply terminals R, S and T and the conductive spots 4 as shown in FIGS. The insulating layer 9 is formed by performing a solder resist process on the conductor pattern P except for. The insulating layer 9 is formed of an insulating ink with a thickness of about 30 μm, for example, by a screen printing method.

Subsequently, except for the power supply terminals R, S, T and the conduction spot 4, a solder resist containing a catalyst such as palladium is used for the entire area of the upper surface of the insulating substrate 5 to make about 3
Resist processing is performed with a thickness of 0 μm. This treatment facilitates subsequent electroless plating. Next, electroless copper plating and electrolytic copper plating are sequentially performed on the entire surface of the insulating substrate 5 including the conductive spots 4.

Next, the R-phase feeding path pattern 1A is shown in FIG.
As shown in FIG. 5, it is formed so as to overlap the upper surface of the insulating layer 9.
This formation is performed by a photographic method using a dry film. That is, if a dry film is laminated on the entire upper surface of the insulating substrate 5 and then a negative film is superposed and exposed / developed, the power feeding path pattern 1A is formed by the subsequent etching process as shown in FIGS. In addition, the conductive spots 4 are formed so as to be electrically connected to the electrode pattern 1.

After the formation of the power feeding path pattern 1A, the remaining conductor portion excluding the power feeding path pattern 1A is removed by etching. Then, the power supply path pattern 1
A second insulating layer 10 is coated on the upper surface of the layer A in order to insulate the layer A and prevent oxidation. In this case, the coating layer of the thermosetting solder resist is formed by printing means. The stator A is completed through the series of processing steps described above. The completed stator A is subjected to punching, cutting and other post-processing required for assembling the electrostatic actuator.

The stator A thus completed is
By performing the flattening process, as shown in the vertical cross section of FIG. 2, the entire upper surface of the conductor pattern P is covered with the adhesive layer 7.
Is flush with the upper surface of the and completely flattened. Since the insulating layer 9 covering the upper surface of the conductor pattern P is formed by screen-printing an insulating ink with an extremely thin and uniform thickness of 30 μm or less, it controls the driving force of the assembled electrostatic actuator. The gaps between the respective electrodes of the stator A and the stator B can be made sufficiently close to each other. Therefore, the driving force of the electrostatic actuator can be maximized. In addition, since the insulating layer 9 is formed to have an extremely uniform thickness, smooth driving is guaranteed.

In this embodiment, as the insulating layer 9, an ink-like composition containing barium titanate, lead titanate or the like as a main component was used in place of the synthetic resin-based insulating ink. It is also possible to form the excellent insulating layer 9.

FIG. 7 shows another embodiment of the present invention and shows a vertical section of a portion of the stator A where the electrode patterns 1 to 3 are formed (corresponding to FIG. 2). The difference from the above-described embodiment is that the insulating layer is formed only in the portion where the electrode patterns 1 to 3 are formed, that is, the portion sandwiched between two parallel two-dot chain lines a and a in the central portion in FIG. The forming method of 9 is changed.

That is, instead of the method of printing the insulating ink on the upper surface of the conductor pattern P, a synthetic resin film 9A such as a polyester film having an adhesive layer 11 on the back surface side.
Laminating (coating) is performed by. This insulating layer 9A made of a synthetic resin film having excellent insulating properties is
Unlike the insulating layer 9 formed by the printing means, there is no pinhole and the structure is dense, so the maximum voltage that can be applied to the electrodes of the stator A is 400 V in the above embodiment.
In contrast to the low torque generation, the device of this embodiment can be increased to 1000 V or higher and can generate high torque. FIG. 8 is a flow sheet showing the manufacturing process of the stator of this embodiment.

In the above structure, the object of the present invention can be achieved even if the detailed structure is appropriately changed in design. For example, as the conductor pattern P, a conductor pattern P which is previously formed and placed on an appropriate transfer base sheet by a printing unit is used.
It may be transferred onto the upper surface of the adhesive layer 7. Further, if necessary, in the flattening step, a press shape having an appropriate shape can be used to shape the stator A into a curved shape or any other shape.

[0023]

As is apparent from the above description, the stator of the electrostatic actuator according to the present invention produced by the method of the present invention exhibits various excellent practical effects as listed below. (A) By performing a flattening process of embedding the electrode pattern and the feeding path pattern in the adhesive layer (insulating layer),
The thickness of the insulating layer that insulates and coats the electrode pattern and the power feeding path pattern is sufficiently thin as compared with the conventional technique, and since the thickness can be sufficiently equalized, the driving force is further increased as compared with the conventional one. In addition, smooth driving is guaranteed, and the electrostatic actuator can be made thinner. (B) Since the power feeding path pattern can be formed in the same process as the electrode pattern, it is possible to surely save the labor and time required for manufacturing the stator. (C) The voltage applied to the stator can be increased without increasing the distance between adjacent electrode patterns or the thickness of the insulating layer that covers the electrode patterns, thus improving the driving performance of the electrostatic actuator. Is achieved. (D) If necessary, in the flattening process, the stator can be formed into any shape.

[Brief description of drawings]

FIG. 1 is a partial perspective plan view of a stator according to an embodiment of the present invention.

FIG. 2 is a vertical sectional view taken along line XX of FIG.

FIG. 3 is a vertical sectional view taken along the line YY of FIG.

FIG. 4 is a vertical sectional view taken along line ZZ of FIG.

FIG. 5 is an explanatory diagram of a step of forming an electrode pattern and a power supply path pattern and a step of flattening the conductive patterns to be embedded in an insulating layer.

FIG. 6 is a flow sheet explaining the manufacturing process of the stator.

FIG. 7 is a view corresponding to FIG. 2, showing another embodiment of the present invention.

FIG. 8 is a diagram corresponding to FIG.

FIG. 9 shows a conventional example and is a perspective view illustrating a schematic configuration of an electrostatic actuator.

FIG. 10 is a vertical sectional view for explaining the operation of the electrostatic actuator.

FIG. 11 is a partial vertical cross-sectional view showing an example of the same as above, in which an electrode pattern on an insulating substrate is insulation-coated.

FIG. 12 is a partial vertical cross-sectional view showing another example of the same as above, in which the electrode pattern on the insulating substrate is insulation-coated.

[Explanation of symbols]

 A stator B mover 1 to 3 electrode pattern 1A to 3A power feeding path pattern P conductor pattern R, S, T power feeding terminal 4 conduction spot 5 insulating substrate 6 copper foil 7 adhesive layer 8 mirror plate 9, 9A insulating layer 10th 2 Insulating layer 11 Adhesive layer a Parallel two-dot chain line 101 Stator 201 Mover 101a, 201a Insulating substrate 102, 202 Dielectric layer 103 Lower electrode 203 Upper electrode 104 Feeding circuit 105 Insulating film 300 Electrostatic actuator b Electrode part c Electrode embedded part d Recessed part g Void

Claims (5)

[Claims] 1. A multi-phase power supply for an electrode pattern, comprising a stator in which a plurality of electrode patterns are arranged in parallel on an insulating substrate, and a mover arranged in parallel with and close to the stator. Voltage is applied to move the stator in the direction parallel to the electrode pattern by the electrostatic force generated between the stator and the mover. The stator is formed on the upper surface of the insulating substrate 5. Electrode patterns 1 to 3 provided via an adhesive layer 7 and power supply path patterns 1A to 3A to the electrodes
At least a part of the above is buried in the adhesive layer 7 so as to be flush with the upper surface of the adhesive layer 7, and the upper surface is covered with insulating layers 9 and 9A. Actuator stator. 2. The stator of the electrostatic actuator according to claim 1, wherein the insulating layer 9A is made of a synthetic resin film. 3. A multi-phase power supply for an electrode pattern, comprising a stator having a plurality of electrode patterns arranged in parallel on an insulating substrate, and a mover arranged so as to be movable in parallel with the stator. In which the stator is moved in the direction parallel to the electrode pattern by the electrostatic force generated between the stator and the mover by applying the voltage of 1. An insulating substrate 5 in a state before crystallization is used as a raw material of the synthetic resin having a property of crystallization by heating.
And a conductor pattern forming step of forming the electrode patterns 1 to 3 and the power feeding path patterns 1A to 3A (conductor pattern P) on the upper surface of the electrode via the adhesive layer 7 having thermosetting property and in a semi-cured state. , The insulating substrate 5 on which the conductor pattern P is formed is subjected to a heat / pressure press treatment so that the conductor pattern P is embedded in the adhesive layer 7 so as to be flush with the insulating substrate 5, and the insulating substrate 5 is changed into a crystal structure and bonded. A method of manufacturing a stator of an electrostatic actuator, comprising: a flattening treatment step of completely curing the agent layer 7; and an insulating step of covering the flattened conductor pattern P with insulating layers 9 and 9A. 4. The conductor pattern P other than the power feeding path pattern 1A among the electrode patterns 1 to 3 and the power feeding path patterns 1A to 3A is embedded in the adhesive layer 7, and the upper surface thereof is covered with the insulating layer 9. Then, the power feeding path pattern 1A is formed on the upper surface of the insulating layer 9, and the power feeding path pattern 1A is electrically connected to the conductive spot 4 provided on the electrode pattern 1, and then the power feeding path pattern 1A and the conductive spot 4 are provided. The method for manufacturing a stator of an electrostatic actuator according to claim 3, wherein the is covered with a second insulating layer 10. 5. The insulating layer 10 of the second insulating layer 10 covering the formation regions of the electrode patterns 1 to 3 is formed by depositing a synthetic resin film. Method for manufacturing a stator of an electrostatic actuator.