JP3545876B2 - Electrostatic film actuator - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an electrostatic film actuator using a thin film.
[0002]
[Prior art]
Conventionally, as the prior art in such a field, for example, there has been the following.
[0003]
As shown in FIG. 6, the electrostatic film actuator is formed by insulating electrodes having a three-phase structure called a first member and a second member by embedding parallel strip-shaped electrodes of equal pitch in which each phase is alternately arranged. It consisted of a film 1 as a member, which was overlapped so that the respective strip electrodes were parallel.
[0004]
[Problems to be solved by the invention]
However, the above-mentioned conventional electrostatic film actuator has the following problems.
[0005]
(1) The upper limit of the generated force of the conventional electrostatic film actuator is determined by the withstand voltage of the first member and the second member if the electrode size and shape are constant. However, in a conventional electrode structure in which three-phase electrodes are alternately arranged as shown in FIG. 6, in the parallel strip electrodes in the first member and the second member, adjacent electrodes are electrodes of different phases. Therefore, a high potential difference is generated between adjacent electrodes, and dielectric breakdown easily occurs at these locations. Therefore, it is difficult to increase the withstand voltage of the film, which hinders the performance improvement of the electrostatic film actuator.
[0006]
(2) When the electrodes of three or more phases are arranged so that the phases are alternately arranged, for example, as shown in FIG. 6, when the film 1 has an α phase, a β phase, and a γ phase, The three-dimensional wiring part 2 is generated. In other words, it is impossible to wire all phases with planar wiring. Therefore, for example, as shown in FIG. 7, the back wiring of the electrode B on the film 1 needs to be performed via the through hole 3 in the three-dimensional wiring part 2 of the electrode. As described above, in order to generate these electrode structures, three-dimensional wiring using the through holes 3 and the like is indispensable, and the manufacturing cost of the electrode film is increased.
[0007]
(3) The conventional electrostatic film actuator has a feature that a large force-to-volume ratio is easily realized by manufacturing the first member and the second member using thin films and laminating a large number of them. In order to take advantage of this advantage, it is desirable that the thickness of the film is as small as possible. However, when an electrode having a three-phase structure as described above is manufactured by three-dimensional wiring, the electrode structure of the film must be a multilayer structure, and it is difficult to suppress the thickness of the film.
[0008]
(4) The arrangement pitch of each electrode in the parallel strip electrode also affects the performance of the electrostatic film actuator. Generally, the performance of the electrostatic film actuator is improved by reducing the electrode arrangement pitch. However, when wiring is performed using through holes, the existence of the through holes becomes a bottleneck, and it is difficult to reduce the arrangement pitch of the electrodes.
[0009]
The present invention improves the withstand voltage of the electrode member used as the moving member / stator by devising the arrangement of the electrodes used for driving the electrostatic film actuator, and also reduces the manufacturing cost and reduces the film thickness. It is an object of the present invention to provide an electrostatic film actuator capable of achieving a reduction in thickness and a finer electrode arrangement interval.
[0010]
[Means for Solving the Problems]
[1] In the first member and the electrostatic film actuator constituted by embedding a plurality of phases of the electrodes in a predetermined pitch in both the insulating member and the second member, pre-Symbol the second member, one parallel strip electrodes for each phase A group is formed, and the electrode group is dispersed and arranged at a predetermined interval, and a three-phase alternating current is applied to the electrode group to form a parallel belt-shaped electrode having a predetermined pitch on the first member. A single-phase alternating current having a frequency three times that of the three-phase alternating current is applied .
[0011]
As described above, in the electrostatic film actuator having the first member and the second member, and the first member and the second member are embedded in the insulating member and having the electrodes arranged at a predetermined pitch, the first member is the first member. And by assembling the electrodes arranged in the second member on at least one of the members as one parallel band electrode group for each phase, and arranging a plurality of electrode groups at predetermined sufficient intervals, The dielectric breakdown inside the member and the second member can be suppressed, and the production of the film can be simplified.
[0012]
Therefore, the necessity of three-dimensional wiring in the manufacture of the electrode is eliminated, and the manufacture of the electrode can be performed only by two-dimensional wiring, so that the manufacturing cost of the film can be reduced, the electrode can be made finer, and the film can be made thinner.
[0013]
Further, in the electrode group of each phase, the same voltage is applied between adjacent electrodes, so that there is no possibility of dielectric breakdown. Only in a place where the electrode groups are adjacent to each other, there is a possibility that a high potential difference is generated, so that a dielectric breakdown may occur.However, by setting a sufficiently large interval between the electrode groups, it is possible to suppress the dielectric breakdown in these places. Can be. Thereby, it is possible to increase the dielectric strength voltage of the first member and the second member.
[0014]
Therefore, a high-performance multi-phase electrostatic film actuator with improved electric durability can be obtained.
[0015]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[0016]
FIG. 1 is a plan view showing an electrode structure of an electrostatic film actuator showing an embodiment of the present invention, FIG. 2 is a plan view of a first member and a second member of the electrostatic film actuator, and FIG. FIG. 2B is a plan view of the first member, and FIG. 2B is a plan view of the second member. FIG. 3 is a perspective view of the electrostatic film actuator, FIG. 4 is a diagram illustrating an example of voltage application to the electrostatic film actuator, and FIG. 5 is a diagram illustrating an example of a voltage pattern applied to the electrostatic film actuator. FIG. 5A shows the applied voltage to the second member, and FIG. 5B shows the applied voltage to the first member.
[0017]
As shown in these drawings, in the first member 10, parallel strip electrodes 12 formed at a predetermined pitch p are embedded in an insulating film 11. Here, the pitch p is, for example, 450 μm.
[0018]
In the second member 20, one parallel strip electrode group is embedded in an insulating film 21 for each phase of the α-phase electrode 22, the β-phase electrode 23, and the γ-phase electrode 24. The α-phase electrode 22, the β-phase electrode 23, and the γ-phase electrode 24 are respectively arranged at a predetermined pitch p, and each phase electrode has an interval D of [m + (１ ／)] p. Here, m is an arbitrary positive integer, but it is desirable to take a certain large value in order to prevent dielectric breakdown in the electrode. For example, m is 15 and interval D is 6900 μm.
[0019]
As described above, one electrode group is formed for each phase, and the electrode groups are dispersedly arranged at a predetermined interval D.
[0020]
Therefore, as shown in FIGS. 4 and 5, the parallel strip-shaped electrodes 12 of the first member 10 by applying a V ₀ sin (3ωt), the α-phase electrodes 22 of the second member 20 V ₀ sin (ωt) , the β-phase electrodes 23 V ₀ sin [ωt + (2/3) π], the γ-phase electrode 24 so as to apply a V ₀ sin [ωt + (4/3) π].
[0021]
That is, the first member 10 and the second member 20 are overlapped as shown in FIG. 3, and the three parallel strip electrode groups 22, 23, and 24 of the second member 20 are shown in FIG. Such a three-phase alternating current is applied to the parallel strip electrodes 12 of the first member 10 by applying an alternating voltage having a frequency three times that of FIG. 5A as shown in FIG. The first member 10 or the second member 20 is linearly driven in the direction indicated by the arrow in FIG. 3 by the electrostatic attraction generated between the two.
[0022]
In the electrode structure in which the three-phase electrodes are arranged alternately as shown in the conventional example, the adjacent electrodes are electrodes of different phases. Dielectric breakdown easily occurs between the electrodes. Therefore, it is difficult to increase the dielectric strength voltage of the entire film.
[0023]
According to the present invention, electrodes of a plurality of phases are assembled for each phase, and the electrodes of each phase are arranged at a sufficient interval D from each other, so that adjacent electrodes are formed in the group of electrodes of each phase. Since the same voltage is applied between them, there is no danger of dielectric breakdown.By arranging the respective electrode groups sufficiently separated, it is easy to increase the dielectric withstand voltage of each electrode film of the mover and stator. is there.
[0024]
Further, the conventional electrode structure requires three-dimensional wiring for manufacturing the electrode, and the wiring of the electrode is usually performed using a film-like substrate having a multilayer structure and through holes. In such wiring, the existence of through holes becomes a bottleneck, making it difficult to miniaturize the electrodes, and the electrodes in the film also have a multi-layer structure, so that the thickness of the film becomes large. These are very serious problems in improving the output of the electrostatic film actuator.
[0025]
According to the electrode arrangement of the present invention, it is possible to manufacture an electrode only with planar wiring, so that no through hole is required, and the electrode is manufactured using a film substrate having an electrode having a single-layer structure. Therefore, it is possible to easily make the electrodes finer and make the film thinner. At the same time, the production cost of the film can be reduced.
[0026]
In the above embodiment, the case where the parallel strip electrodes are arranged on a plate-like film has been described. However, as the electrostatic film actuator, a known technique (for example, Japanese Patent Application Laid-Open No. 6-78566 and Japanese Patent Application Laid-Open No. Needless to say, the present invention can be applied to the case where the electrodes are radially arranged in a disk-shaped insulator (see 194147 and JP-A-7-274540).
[0027]
Further, it is needless to say that the present invention can be applied to a case where electrodes are wound in a cylindrical insulator.
[0028]
It should be noted that the present invention is not limited to the above embodiment, and various modifications are possible based on the spirit of the present invention, and these are not excluded from the scope of the present invention.
[0029]
【The invention's effect】
According to the present invention, the following effects can be further obtained while retaining many features of the electrostatic actuator having the film-shaped movable member and stator.
[0030]
(1) According to the present invention, the withstand voltage of the first member and the second member serving as the moving member and the stator is greatly improved as compared with the related art, and the generation force of the electrostatic film actuator is improved, and the electric durability is improved. Performance can be improved.
[0031]
Further, in the manufacture of the electrodes of the first member and the second member, the electrodes can be formed by planar wiring without the need for a mechanism such as a through hole or the like. The arrangement pitch can be made finer, and the production cost of the electrode film can be reduced.
[0032]
Therefore, a high-performance multi-phase electrostatic film actuator with improved electric durability can be obtained.
[Brief description of the drawings]
FIG. 1 is a plan view showing an electrode structure of an electrostatic film actuator showing an embodiment of the present invention.
FIG. 2 is a plan view of a first member and a second member of the electrostatic film actuator according to the embodiment of the present invention.
FIG. 3 is a perspective view of an electrostatic film actuator showing an embodiment of the present invention.
FIG. 4 is a diagram illustrating an example of voltage application to an electrostatic film actuator according to an embodiment of the present invention.
FIG. 5 is a diagram illustrating an example of a voltage pattern applied to an electrostatic film actuator according to an embodiment of the present invention.
FIG. 6 is a plan view showing an electrode structure of a three-phase electrode of a conventional electrostatic film actuator.
FIG. 7 is a sectional view showing a three-dimensional wiring portion of an electrode of a conventional electrostatic film actuator.
[Explanation of symbols]
Reference Signs List 10 First member 11, 21 Insulating film 12 Parallel strip electrode 20 Second member 22 α-phase electrode 23 β-phase electrode 24 γ-phase electrode

Claims (1)

An electrostatic film actuator in which the first member and the second member are configured by embedding a plurality of phase electrodes having a predetermined pitch in an insulating member.
Before Stories second member, one parallel strip electrodes formed for each phase, as well as placing the electrodes distributed and with a predetermined interval, applying a 3-phase alternating current to the electrode group, the first An electrostatic film actuator wherein a parallel strip electrode having a predetermined pitch is formed on a member, and a single-phase alternating current having a frequency three times that of the three-phase alternating current is applied to the electrode.

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