JP2004112884A - Electrostatic actuator and conveyance apparatus using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrostatic actuator and a conveyance apparatus using the actuator capable of preventing band-type electrodes of a mover and/or a stator or insulation membranes on the band-type electrodes from hitting each other. <P>SOLUTION: The electrostatic actuator is formed by making the stator in which the plurality of band-type electrodes are formed on a base material surface in face to face with the mover in which the plurality of band-type electrodes are formed on the base material surface. In the actuator, a protruding section is formed on a surface except the band-type electrodes of the stator and/or the mover in order to prevent the ban-type electrodes from hitting each other. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an electrostatic actuator driven by an electrostatic force, and a transport device using the same.
[0002]
[Prior art]
FIG. 8 shows what is called an AC-driven double-electrode electrostatic actuator. This electrostatic actuator is composed of a stator 1 and a mover 2. Both the stator 1 and the mover 2 have a number of strip-shaped electrodes 3 connected in three phases, and the surfaces are covered with an insulating film 4. One three-phase sine wave is applied to both the stator 1 and the mover 2 such that the connection order is reversed. As a result, a sine-wave potential distribution 5 that travels in the opposite direction is generated on the stator 1 and the movable element 2. The actuator is driven by the electrostatic force acting between these two potential distributions.
[0003]
Conventionally, as a transfer device using an electrostatic actuator composed of a moving element having a plurality of strip electrodes arranged thereon and a stator having a plurality of strip electrodes arranged thereon, the moving element is used as a transfer section of an object to be transferred, and one end thereof is provided. The other end is attached to the mover side and the other end is movably contacted with the stator, and the movement path of the mover with respect to the stator is restricted to a specific trajectory in the electrode array direction. It is disclosed that a guide is provided with a slider floating means for blowing air to the slider in order to reduce the weight of the slider via a contact acting on the stator. 1).
Further, in order to reduce the friction between the moving element and the stator, an electrostatic actuator in which a concavo-convex pattern is provided on the moving element and / or the stator or holes are provided (for example, see Patent Document 2) ).
[0004]
[Patent Document 1]
JP-A-7-206204 (page 4, FIG. 2)
[Patent Document 2]
JP-A-4-340371 (pages 3-7, FIG. 1)
[0005]
[Problems to be solved by the invention]
In the transfer device using the electrostatic actuator described in Patent Literature 1, when an abnormality occurs in the floating means for floating the moving element by air, the moving element and the stator may collide with each other. If there is no insulating film on the strip electrodes of the mover and / or the stator, the collision will cause a short circuit in the circuit. Even if there is an insulating film on the strip electrodes of the mover and / or stator, the collision may damage the mover and the insulating film on the stator surface, which may cause dielectric breakdown. is there. Further, in the electrostatic actuator described in Patent Literature 2, there is a problem that the insulator may be damaged if the stator is used for a long period of time because the stator and the slider rub when the slider moves. This is considered to be a problem particularly when the weight of the moving element is large.
[0006]
SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide an electrostatic actuator in which the strip electrodes of the moving element and / or the stator or the insulating films on the strip electrodes do not collide with each other, and An object of the present invention is to provide a transfer device using the same.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, according to the present invention, a stator having a plurality of strip-shaped electrodes formed on the surface of a substrate and a moving element having a plurality of strip-shaped electrodes formed on the surface of the base are opposed to each other. Provided is an electrostatic actuator, wherein a convex portion is formed on a surface portion of the stator and / or the mover other than the band-shaped electrode portion.
Here, the convex portions may be provided linearly, or may be provided in the form of dots. If it is linear, it is preferably provided at both ends, and if it is point-like, it is preferably provided at least at four corners. Even if the moving element and the stator collide, it is possible to prevent the strip-shaped electrodes from collapsing. Further, since an insulating film is not necessary, it is possible to contribute to cost reduction.
[0008]
In another aspect of the present invention, a plurality of strip-shaped electrodes are formed on the surface of the base material, and the stator in which the strip-shaped electrodes are covered with an insulating film, and a plurality of strip-shaped electrodes are formed on the surface of the base material, and In the electrostatic actuator in which the strip-shaped electrode faces a moving element covered with an insulating film, a protrusion is formed on a surface portion of the stator and / or the moving element other than the strip-shaped electrode section. An electrostatic actuator is provided.
Even if the mover and the stator collide, it is possible to prevent the insulating films from collapsing.
[0009]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a front view of an electrostatic actuator according to a first embodiment of the present invention, and FIG. 2 is a cross-sectional view of FIG. In FIG. 1, the stator 1 has a strip electrode 3 formed thereon, and the strip electrode 3 is covered with an insulating film 4. Similarly, a strip-shaped electrode 3 is formed on the movable element 2, and the strip-shaped electrode 3 is covered with an insulating film 4. The moving element 2 is further provided with linear projections 6 at both ends of the outer peripheral surface. The insulating film 4 of the stator 1 and the insulating film 4 of the movable element 2 are arranged with a gap of several μm to several tens μm.
The height of the convex portion 6 is several μm to several tens μm smaller than the gap. Since the protrusions 6 are provided, even if the stator 1 and the moving element 2 collide with each other, the insulating films 4 formed on the stator 1 and the moving element 2 do not collide with each other. There is no damage to the film 4 and no dielectric breakdown occurs.
[0010]
FIG. 3 is a front view of an electrostatic actuator according to a second embodiment of the present invention, and FIG. In FIG. 3, the stator 1 has a strip electrode 3 formed thereon. Similarly, the strip 2 is formed on the movable element 2. The moving element 2 is further provided with linear projections 6 at both ends of the outer peripheral surface. Since the protrusions 6 are provided, even if the stator 1 and the moving element 2 collide, the band-shaped electrodes 3 formed on the stator 1 and the moving element 2 do not collide with each other. Never short-circuit.
FIG. 5 is a front view of an electrostatic actuator according to a third embodiment of the present invention, and FIG. 6 is a cross-sectional view of FIG. In FIG. 5, the stator 1 has a strip electrode 3 formed thereon. Similarly, the strip 2 is formed on the movable element 2. The moving element 2 is further provided with dot-shaped convex portions 6 at four locations on the outer peripheral surface. Since the protrusions 6 are provided, even if the stator 1 and the moving element 2 collide, the band-shaped electrodes 3 formed on the stator 1 and the moving element 2 do not collide with each other. Never short-circuit.
[0011]
As a material of the base material of the stator 1 and the moving element 2, a rigid body such as ceramics or glass is used. The thickness is changed as necessary from several tens μm to several tens mm depending on required rigidity and the like.
As the material of the belt-shaped electrode 3, an electrode material such as gold, silver, platinum, copper, aluminum, titanium, chromium, tungsten, molybdenum, TiC, and ITO is used. As a manufacturing method, a manufacturing method according to the material, such as plating, PVD, CVD, printing, and transfer, is adopted. The thickness is 0. Adjust from several μm to several tens μm according to the material and manufacturing method.
As a material of the insulating film 4, an insulating material such as ceramics, glass, or polyimide is used. As a manufacturing method, a manufacturing method according to the material, such as PVD, CVD, printing, a sol-gel method, or a thermal spraying method, is employed. The thickness is adjusted from several μm to several hundred μm according to the material and manufacturing method.
As a method of forming the convex portion 6, the base material of the stator 1 and / or the movable member 2 may be formed in advance so that the band-shaped electrode forming portion becomes a concave portion by grinding or the like, or the stator 1 and / or the moving portion may be moved. A plate material such as metal, ceramics, glass, or resin is attached to a portion other than the band-shaped electrode portion of the child 2, for example, an outer peripheral portion, or the convex portion 6 is formed by PVD, CVD, printing, a sol-gel method, a thermal spraying method, or the like. The height of the projection 6 is larger than the thickness of the strip electrode 3 or the insulating film 4 and is smaller than the gap between the stator 1 and the moving element 2. It is adjusted from several μm to several hundred μm according to the material and the manufacturing method. In the case where convex portions are provided on both the stator and the movable member, and the convex portions surely contact each other when the movable member and the stator come into contact with each other, the both convex portions may be included in the above range.
[0012]
FIG. 7 is a side view of a transfer device using the electrostatic actuator according to the first embodiment of the present invention. The stator 1 is fixed on a base 10, and the mover 2 is fixed on a stage 7 supported by a guide shaft 8.
FIG. 8 is a side view of an AC driven double electrode type electrostatic actuator.
[0013]
【The invention's effect】
According to the present invention, even if the movable member and the fixed member collide with each other, the band-shaped electrodes of the movable member and / or the stator, or the insulating films on the band-shaped electrode do not collide with each other. And dielectric breakdown can be prevented.
[Brief description of the drawings]
FIG. 1 is a front view of a first embodiment according to the present invention; FIG. 2 is a cross-sectional view as viewed from A of a first embodiment according to the present invention; FIG. 3 is a front view of a second embodiment according to the present invention; FIG. 5 is a front view of a third embodiment according to the present invention. FIG. 6 is a cross-sectional view of a third embodiment according to the present invention as viewed from C. FIG. 7 is an embodiment of the present invention. FIG. 8 is a side view of an AC-driven double-electrode type electrostatic actuator.
DESCRIPTION OF SYMBOLS 1 ... Stator, 2 ... Moving element, 3 ... Strip electrode, 4 ... Insulating film,
5: sinusoidal potential distribution, 6: convex part, 7: stage,
8 Guide shaft, 9 Support, 10 Base

Claims (3)

In an electrostatic actuator in which a stator having a plurality of band-shaped electrodes formed on the surface of a base material and a moving member having a plurality of band-shaped electrodes formed on the surface of the base material are opposed to each other, a stator and / or a moving element are provided. A convex portion is formed on a surface portion other than the strip-shaped electrode portion. A stator in which a plurality of strip-shaped electrodes are formed on the surface of a base material and the strip-shaped electrodes are covered with an insulating film, and a plurality of strip-shaped electrodes formed on the surface of the base material and the strip-shaped electrodes are covered with an insulating film An electrostatic actuator in which a moving element is opposed to a moving element, wherein a projection is formed on a surface portion of the stator and / or the moving element other than the band-shaped electrode portion. A transfer device using the electrostatic actuator according to claim 1.

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