JPH0365081A - Electrostatic motor - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an electrostatic motor, and more specifically, to a stator in which a plurality of electrodes are periodically arranged, and a stator with a predetermined distance between the stator and the stator. An electrostatic device that is relatively movable and has a movable element with multiple electrodes arranged at the same period as the stator, and uses the electrostatic force generated by applying a voltage between the electrodes of the stator and the movable element as a driving force. Regarding motors.

[Prior Art J] Recently, with the progress of microtechnology, research on the use of electrostatic motors as microactuators has been actively conducted. In an electrostatic motor, a substrate supporting a plurality of periodically arranged electrodes is used as a movable element, and a similarly periodically arranged electrode substrate is arranged as a stator, and each electrode of the stator and the movable element This is a motor that uses the electrostatic attractive force generated between the electrodes as its driving force by applying a driving voltage to the electrode.

Compared to electromagnetic motors, which have been the mainstream in the past, electrostatic motors have a simpler structure, are ultra-small, and consume less power, so they are expected to be used as microactuators, something that cannot be achieved with electromagnetic motors. has been done. As such an ultra-small actuator, for example, a linear electrostatic motor is described in Japanese Patent Application Laid-Open No. 136978/1983. In this electrostatic motor, Figs.
As shown in the figure, the three-phase electrodes 31 to 33 and the moving center of the mover are arranged on the stator 30 at a predetermined pitch offset from each other, *
Electrodes 31' to 33° arranged symmetrically with respect to x-x'
is arranged, and on the other hand, an electrode 36 is formed on the movable element 35 with a length that crosses each electrode of the stator, and a voltage is applied between each electrode of the stator and the movable element to generate an electrostatic force. I'm letting you do it.

[Problems to be Solved by the Invention] In the case of such a conventional electrostatic motor, the reason why the three-phase electrodes 31 to 33 and 31° to 33'' arranged on the stator are arranged symmetrically is because of rotation. This is to prevent moment generation, and in the case of an electrostatic motor with a symmetrical phase structure like this, if it is a 3-phase structure, at least a 6-phase structure is required as shown in Figure 7. This has the drawback of complicating the electrode structure and generating pullback force against lateral displacement.

Furthermore, in the case of an electrostatic motor, the distance between the electrodes of the stator and movable element is made as narrow as possible in order to increase the generated electrostatic force. If conductive dust exists between the electrodes of the stator and mover that face each other at such a narrow interval, there is a problem in that the voltage supply line may be short-circuited and the electrodes may be destroyed. In addition, in conventional electrostatic motors, voltage is supplied through one voltage supply line provided to each electrode, so if mechanical friction occurs due to dust, etc., the voltage supply line may be disconnected. However, there was a drawback that normal operation of the electrostatic motor could not be guaranteed.

Therefore, the present invention has been made to eliminate these conventional drawbacks, and has a simple electrode structure and is not affected by dust etc. existing between the electrodes of the stator and mover. An object of the present invention is to provide an electrostatic motor that can guarantee reliable operation.

[Means for Solving the Problems] In order to solve such problems, the present invention provides a stator in which a plurality of electrodes are arranged periodically, and a stator that moves relative to the stator while maintaining a predetermined interval. In an electrostatic motor, which is equipped with a movable element having a plurality of electrodes arranged at the same period as the stator, and whose driving force is an electrostatic force generated by applying a voltage between the electrodes of the stator and the movable element. A configuration was adopted in which voltage supply lines were provided on both sides of the stator and mover electrodes along the direction of movement.

[Function] In such a configuration, the voltage supply line is provided not only on one side of the electrode but on both sides, and the moment component perpendicular to the moving direction of the mover is equal to the static voltage of the two voltage supply lines on both sides. Since it is fixed by electric power and no rotational moment is generated, the electrode structure can be simplified even if it is a multiphase structure. Further, since voltage supply lines are provided on both sides of each electrode, even if one voltage supply line is disconnected, there is another voltage supply line, so it is possible to prepare for unexpected situations.

[Example] Hereinafter, the present invention will be described in detail according to an example shown in the drawings.

FIG. 1 shows the overall structure of an electrostatic motor according to an embodiment of the present invention, and the reference numeral 1 in the figure is a mover, as shown in FIG. To,
For example, 27mmX70mm%'0.7m that has been thoroughly cleaned.
It consists of a thin film glass substrate 3 of n+ size and an upper electrode 4 placed thereon. A stator 2 that is movable relative to the movable element l while maintaining a predetermined distance is arranged,
This stator 2 is composed of a thin film glass substrate 5 similar to that of the mover 1, on which a lower electrode 6 is arranged.

The lower electrode 6, as shown in detail in FIG.
It is made up of three comb-shaped electrodes 6a, 6b, and 6c to which three-phase voltages φA, φB, and φC are applied.
(a) X6mm (C) and pitch (b) is 60
It is constructed by periodically arranging unit electrodes of 6° each having a diameter of μm. Each of the electrodes 6a, 6b, and 6c is arranged periodically with a predetermined phase, in this embodiment, a phase shift corresponding to one-third pitch.
Voltage supply lines 19.19', 19'' are formed on both sides of the electrodes b and 6C along the moving direction, and three-phase voltages φA, φB, and φC are applied to each electrode on this voltage supply line 19. .19°, 19″.

On the other hand, the upper electrode 4 is an electrode 4a as shown in FIG.
, 4b, and 4C, and the electrodes 4a, 4b, and 4C are respectively formed of lower electrodes 6a, 4b, and 4C.
They are arranged corresponding to 6b and 6C. The unit electrode 4' of the upper electrode also has the same size as the unit electrode 6' of the lower electrode. Further, the electrodes 4a, 4b, 4C are the electrodes 6a,
Unlike 6b and 6C, they are arranged periodically without shifting the phase. In addition, voltage supply lines 22, 22', 22'' are formed on both sides of the electrodes 4a, 4b, 4C along the moving direction in the same way as the lower electrode. The supply line is formed in one piece and is connected to earth 23 in its entirety.

1 These stator and mover electrodes are manufactured in the same process as follows. That is, first, about 100 losses of molybdenum are vapor-deposited on each substrate 3.5. Subsequently, after applying a resist agent, a photomask is placed on the surface and patterning is performed using ultraviolet rays. RIE (
By etching molybdenum using reactive ion etching (reactive ion etching), the microfabricated upper electrode 4 and lower electrode 6 are patterned, respectively.
After removing the resist agent, use a metal mask to apply 5i0
Two layers 7.8 were deposited at about 1000A, each with upper electrode 4
, covering the lower electrode 6. The movable element 1 and the stator 2 produced in this manner are placed facing each other, and the gap between the electrodes 4.6 is maintained at approximately 101 m to construct the entire electrostatic motor.

FIG. 5 shows a drive circuit diagram for driving the electrostatic motor configured as described above. In the figure, a clock is sent from an oscillator 14, a signal is input to a counter 15, and a signal whose frequency is divided by three is obtained from the counter 15. This signal and the oscillator clock are input to the shift register 16 to obtain three-phase rectangular wave signals whose phases are shifted by 120 degrees from each other. After that, it passes through the booster 17 and becomes 3 as shown in FIG.
Obtain a rectangular wave signal with a phase of 100V.

In such a configuration, voltages φA, φB, and φC that are 120' out of phase with each other as shown in FIG. 6 are applied to the voltage supply pads 18 of the electrodes 6a, 6b, and 6C of the stator 2. The applied voltage is the voltage supply line 19.1 of each phase.
9° and 19" to the electrode portions 20 of each phase. In this case, if electrodes 4a and 6a overlap, adjacent electrodes are shifted by 1/3 pitch, so electrode 4b The ends of the two electrodes 4a, 4b, and 6b are in contact with each other.The phases of the upper electrodes 4a, 4b, and 4C are always grounded.

If charge is stored in the electrode 6a, it is discharged and the electrode 4b is
A φB phase voltage is applied to the electrode 6b. The electrodes are attracted to each other by electrostatic force and move until the electrodes 4b and 6b overlap. At this time, the ends of the two electrodes, electrode 4c and electrode 6c, are in contact with each other. Similarly, the electric charge stored in the electrode 6b is discharged, and a φC phase voltage is applied to the electrode 4c and the electrode 6c. Thereafter, by repeating the same procedure to move the electrodes, it can be driven as a motor.

In such a configuration, the voltage supply lines 19.19°, 1
9" and 22.22° 22" are provided on both sides along the moving direction of the electrode, and the moment component perpendicular to the moving direction of the mover is fixed by the electrostatic force of the two voltage supply lines on both sides. Since rotational moment is no longer generated, the electrode structure can be simplified even if a multi-phase structure is used.6 Also, since voltage supply lines are provided on both sides of each electrode, only one voltage supply can be used. Even if a line is disconnected, there is another voltage supply line, so the electrostatic motor can operate without any problem.

Furthermore, in the above-described embodiments, an electrostatic motor with a three-phase structure was described, but the feature of the present invention is that voltage is supplied to both sides of each electrode of the stator and mover of the electrostatic motor along the direction of movement. It has a structure in which lines are provided, and in principle, it can also be applied to electrostatic motors with an 1-phase structure or a multi-phase structure with 3 or more phases.

Furthermore, in the embodiment described above, the electrode holding substrate 3.5
In addition to the glass substrate, a polymer substrate (PMMA) can also be used. In addition to molybdenum, high melting point metals or conductive polymer films can also be used as electrode materials.

[Effect of the Invention 1] As explained above, in the present invention, voltage supply lines are provided on both sides of each electrode of the stator and mover of the electrostatic motor along the direction of movement, so that The moment component perpendicular to the traveling direction is fixed by the electrostatic force of the two voltage supply lines on both sides, no rotational moment is generated, and the electrode structure can be simplified even if it is a multiphase structure. In addition, since voltage supply lines are provided on both sides of each electrode, even if one voltage supply line is disconnected, there is another voltage supply line, so the operating force S of the electrostatic motor is normal. Guaranteed.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing the overall structure of the electrostatic motor of the present invention, FIG. 2 is a structural sectional view of the electrostatic motor of FIG. 1, and FIG.
Figure 4 is an explanatory diagram showing the structure of the stator, Figure 4 is an explanatory diagram showing the structure of the mover, Figure 5 is an electrostatic motor drive circuit diagram, Figure 6 is a timing chart of applied voltage, and Figure 7 is an explanatory diagram showing the structure of the stator. FIG. 8 is an explanatory diagram showing the structure of a stator of a conventional electrostatic motor, and FIG. 8 is an explanatory diagram showing the structure of a movable element of a conventional electrostatic motor. l-...Mover, 2--Identifier, 3...Substrate,
4...upper electrode, 6-...lower electrode, 19.19
', 19'', 22.22°, 22''...voltage supply line

Claims (1)

[Claims] 1) A stator in which a plurality of electrodes are arranged periodically, and a stator that is movable relative to the stator while maintaining a predetermined interval, and in which the plurality of electrodes are arranged in the same period as the stator. In an electrostatic motor, which is provided with a movable element and whose driving force is an electrostatic force generated by applying a voltage between the electrodes of the stator and the movable element, both sides along the moving direction of each electrode of the stator and the movable element. An electrostatic motor characterized in that each of the electrostatic motors is provided with a voltage supply line. 2) A claim characterized in that at least three phase electrodes are arranged on the stator and are shifted from each other by a predetermined pitch, and voltage supply lines are provided on both sides along the moving direction of the electrodes of each phase. The electrostatic motor according to item 1.