JPH04275072A - Microstepwise driving method and device for filmlike article - Google Patents

Abstract

PURPOSE:To microscopically drive a filmlike article at a microstep of an electrode pitch of less by incorporating a low resistance value in the article and suitably controlling a pattern of a voltage to be applied to electrodes. CONSTITUTION:In a microstep driving device for a filmlike article, a stator 21 having a plurality of stripelike electrodes 24 arranged in an insulator 22, and a filmlike article 30 set on the stator 21 and having a filmlike insulator layer 31 and a low resistance layer 32, are provided. The article 30 is driven at a micropitch smaller than a pitch of the electrodes 24 by switching a voltage to the electrodes 24.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a microstep drive device for a film-like object and a microstep drive method thereof.

0002

[Prior Art] Conventionally, technologies in this field include:
There is something described in Japanese Patent Laid-Open No. 2-285978 filed by the applicant of this patent. FIG. 18 is a perspective view of an electrostatic actuator using such a conventional film, and FIG. 19 is a configuration diagram of the electrostatic actuator.

As shown in these figures, an electrostatic actuator using a film includes a stator 1 having a plurality of strip electrodes 4 wired inside an insulator 2, and a stator 1 placed on the stator 1. , comprising a mover 10 made of a film-like insulator layer 11 and a high-resistance layer 12, and means for floating and driving the mover 10 and positioning it by switching the voltage to the strip electrode 4. ing.

[0004] This will be explained in detail below. The lower stator 1 has a plurality of strip electrodes 4 embedded in an insulator 2. On the other hand, the mover 10 is made up of a film-like insulator layer 11 and a high-resistance layer 12, and is placed on the stator 1 in a contacting state. First, a voltage is selectively applied to the band-shaped electrode 4 as described later to charge (induce) charge into the high-resistance layer 12 . Thereafter, by switching the voltage, the moving element 10 is moved one pitch at a time while floating. Incidentally, for example, the width l1 of the strip electrode 4 is 0.4 mm, the pitch l2 of the strip electrode 4 is 1.27 mm, the overall width l3 where the strip electrode 4 is arranged is 126 mm, and the length of the strip electrode 4 is 175 mm. .

Next, one pitch operation of this electrostatic actuator will be explained with reference to FIG. 20. first,
As shown in FIG. 20(a), electrodes 4a1 and 4, which are the first electrode group embedded in the insulator 2 constituting the stator 1,
A positive voltage +V is applied to a2 and 4a3, a negative voltage -V is applied to electrodes 4b1, 4b2 and 4b3 which are the second electrode group, and 0V is applied to electrodes 4c1, 4c2 and 4c3 which are the third electrode group. Then, a current flows in the high-resistance layer 12, which had no charge at first, and a charge is induced at the boundary between the high-resistance layer 12 and the film-like insulator layer 11, resulting in an equilibrium state. This charge can be replaced by a mirror image charge at the position indicated by the dotted line in FIG. 20(b). In this state,
The mover 10 is attracted to the stator 1.

Next, as shown in FIG. 20(c), the voltage applied to each electrode is switched. That is, the negative voltage -V is applied to the electrodes 4a1, 4a2, 4a3 which are the first electrode group, the positive voltage +V is applied to the electrodes 4b1, 4b2, 4b3 which are the second electrode group, and the electrodes 4c1, 4c2 which are the third electrode group. ，
A negative voltage -V is applied to each of 4c3. Then, the charges within each electrode move instantaneously, but the mirror image charges induced in the high-resistance layer 12 cannot move immediately because of their high resistance value. Since the charges on the electrodes 4a1, 4b1, 4a2, and 4b2 and the mirror image charges thereon have the same sign, a repulsive force is generated and the movable element 10 floats. Further, the negative charge on the electrode 4c1 and the mirror image + charge on the electrode 4b1 are attracted, and the electrode 4c1
Since the charge on the electrode 4a2 and the mirror image charge on the electrode 4a2 repel each other, the moving element receives a rightward driving force and moves to the right.

Therefore, when the mover 10 moves one pitch (l2: 1.27 mm) to the right, the charge on the electrode and the mirror image charge thereon become different in polarity, as shown in FIG. 20(d). Therefore, the suction force works and the mover stops there. Next, as shown in FIG. 20(e), 0V is applied to the electrodes 4a1, 4a2, and 4a3 that are the first electrode group, and positive voltage +V is applied to the electrodes 4b1, 4b2, and 4b3 that are the second electrode group.
, electrodes 4c1, 4c2, 4c3 which are the third electrode group
A negative voltage -V is applied to.

[0008] Then, while the movable element is moving, the mirror image charge is diffused, thereby inducing (charging) the mirror image charge again. The mover 10 of this actuator has no electrodes, and the pattern of the band-shaped electrode 4 of the stator 1 is transferred to the mover 10 by the charging operation, so there is no need to align the mover 10 with respect to the stator 1, and the band-shaped electrode The high-precision machining described in step 4 is not required.

Furthermore, since this actuator maintains the gap by bringing the stator 1 and the mover 10 into contact, the gap can be made as narrow as possible. In this case, friction between the two becomes a problem, but here the friction is eliminated by making the mover 10 levitate using electrostatic force. Sensors and complicated control are required to keep the mover 10 afloat at all times, but here a method is adopted in which the mover 10 is temporarily levitated only when being driven. Therefore, sensors and complicated controls are not required.

As mentioned above, the electrostatic actuator of the method described here has a simple structure, does not require precision, and does not require complicated control, so it is easy to manufacture, and both the stator and mover are easy to manufacture. Easy to make into a film. Further, since the volume required for parts that are not essential in terms of electrostatic force generation, such as the gap holding mechanism and the control circuit, can be reduced as much as possible, the force density of the actuator as a whole can be increased. In particular, when the mover and stator are made into a film, the thickness relative to the area becomes extremely thin, so there is no wasted space and the force density can be increased.

[0011] The material for the film can be selected from among many types of polymer films. Many polymer films are excellent insulators and can withstand high electric fields, making them suitable materials for electrostatic actuators.

0012

However, as described above, the drive step in this type of actuator is limited to the pitch l2 of the strip electrodes 4, that is, 1.2.
7 mm, and a further micro step drive device is desired to perform fine operations. If micro-drive becomes possible with such a micro-positioning device, it will become possible to perform micro-paper feeding for high-quality printing in printers and facsimile machines, and micro-positioning when printing on films, fabrics, etc., which have been difficult in the past.

[0013] In view of the above-mentioned circumstances, the present invention has been developed to form a film-like object in minute steps smaller than the electrode pitch by providing a moving body with a low resistance value and appropriately controlling the pattern of the voltage applied to the electrodes. It is an object of the present invention to provide a microstep driving device for a film-like object and a microstep driving method thereof, which are capable of microscopic driving.

[0014]

[Means for Solving the Problems] In order to achieve the above object, the present invention provides (A) a microstep drive device for a film-like object, which includes a stator having a plurality of strip electrodes wired inside an insulator; , a film-like object set on the stator and consisting of a film-like insulator layer and a low-resistance layer is provided, and by switching the voltage to the band-shaped electrode, the film-like object has a pitch smaller than the band-shaped electrode pitch. A means for driving at a minute pitch is provided. (B) A microstep drive device for a film-like object, which includes a stator including a plurality of strip electrodes wired inside an insulator, a film-like object set on the stator, and a film-like object on the surface of the film-like object. means for applying high-density positive and negative charges, and means for driving the film-like object at a minute pitch smaller than the pitch of the strip-shaped electrodes by switching the voltage to the strip-shaped electrodes. . (C) Microstep drive of a film-like object in which a film-like object is set on a stator having a plurality of strip-like electrodes wired inside an insulator, and the film-like object is driven by switching the voltage to the strip-like electrodes. In the method, the electrical resistance of the surface of the film-like object is set low, and the voltage applied to the strip-shaped electrodes is switched to drive the film-shaped object at a minute pitch smaller than the pitch of the strip-shaped electrodes. (D) A microstep drive device for a film-like object, which includes a stator including a plurality of strip-shaped electrodes wired inside an insulator, and a film-like insulator layer and a high-resistance layer set on the stator. A film-like object is provided, and means is provided for driving the film-like object at a minute pitch smaller than the pitch of the band-like electrodes by switching the voltage to the band-like electrodes. (E) A microstep drive device for a film-like object, which includes a stator including a plurality of strip electrodes wired inside an insulator, a film-like object set on the stator, and a film-like object on the surface of the film-like object. means for applying positive and negative charges with low density, and means for driving the film-like object at a minute pitch smaller than the pitch of the strip-shaped electrodes by switching the voltage to the strip-shaped electrodes. . (F) Microstep drive of a film-like object in which a film-like object is set on a stator having a plurality of strip-like electrodes wired inside an insulator, and the film-like object is driven by switching the voltage to the strip-like electrodes. In the method, (a)
The electrical resistance of the surface of the film-like object is set high, and (
b) The voltage applied to the strip electrodes is switched to drive the strip electrodes at a minute pitch smaller than the pitch of the strip electrodes.

[0015] In step (b) above, the first strip-shaped electrode is set to a first potential, the second strip-shaped electrode is set to a second potential,
The third strip electrodes are each set to a third potential, and then:
The first strip electrode is set to the second potential, and the second strip electrode is set to the first potential.
After driving the film-like object by setting the first strip electrode to the first potential and the third strip electrode to the second potential, the first strip electrode is set to the first potential and the second strip electrode is set to the second potential. to the potential, the third
The band-shaped electrodes are each set to a fourth potential, and after moving by the electrode pitch, they are pulled back to perform minute step driving.

[0016]

[Function] According to the present invention, (A) As shown in FIG.
1, a film-like object 30 consisting of a film-like insulator layer 31 and a low-resistance layer 32 is provided, and by switching the voltage to the strip electrode 24, the film-like object 30 is set on the low-resistance layer 32. Since the resistance value of the film-like object 30 is low, the induced charge is
Since the time constant is short, the time that the film-like object 30 can remain at the original position in the electrode 1 is shortened.
Before the film-like object 30 is completely moved by the pitch, the charges within the film-like object 30 disappear. At that point, the film-like object 30 loses its rightward driving force and comes to rest. in this way,
Since the time constant is short, the amount of movement lp (see FIG. 3) has a value much smaller than the electrode pitch. By repeating such operations, minute step driving is performed.

[0017] Furthermore, the surface resistance value of the low resistance layer is 10
It is 11 to 1014Ω/□. (B) As shown in FIG. 6, a stator 41 including a plurality of strip electrodes 44 wired within an insulator 42, and the stator 4
1, and means for imparting high-density positive and negative charges to the surface of the film-like object 50, and by switching the voltage to the strip electrode, the film-like object 50 is set on the surface of the film-like object 50. The shaped object 50 is driven at a minute pitch smaller than the pitch of the strip-shaped electrodes. (C) Therefore, by setting the resistance value of the film-like object to be smaller than that in normal driving, it is possible to perform fine step driving of, for example, about 1/20 of the electrode pitch. (D) As shown in FIG. 10, a stator 63 includes a plurality of strip electrodes 65 wired within an insulator 64, a film-like insulator layer 67 set on the stator 63, and a high resistance A film-like object 66 consisting of a body layer 68 is provided, and by switching the voltage to the strip-like electrode 65, the film-like object 66 is driven at a minute pitch smaller than the pitch of the strip-like electrode.

First, as shown in FIG. 10(1), a positive voltage +VO is applied to the electrode 65a1 which is the first electrode group embedded in the insulator 64 constituting the stator 63, and a positive voltage +VO is applied to the electrode 65a1 which is the second electrode group. A negative voltage -VO is applied to the electrode 65b1, and 0V is applied to the electrode 65c1, which is the third electrode group. Then, a current flows in the high-resistance layer 68 of the film-like object 66, which initially had no charge, and a charge is induced at the boundary between the high-resistance layer 68 and the insulator layer 67, resulting in an equilibrium state. In other words, when the voltage shown in FIG. 10(1) is applied to each electrode, after a time sufficiently longer than the time constant, the film-like object 66
A charge is induced as shown in the figure. At this time, the position where the film-like object 66 is stable is the position where the charge is directly above each electrode.

Next, assuming that the time constant of the film-like object 66 is sufficiently long and the induced charge charged in FIG. 10(1) is fixed on the film-like object 66, as shown in FIG. 10(2), When a voltage is applied, that is, a positive voltage +VO is applied to the electrode 65a1 that is the first electrode group, a negative voltage -VO is applied to the electrode 65b1 that is the second electrode group, and a negative voltage - is applied to the electrode 65c1 that is the third electrode group. The stable point when applying V1 is slightly displaced to the right in the figure compared to the case of FIG. 10(1). The amount of displacement is controlled by the voltage applied to the rightmost electrode, that is, the electrode 65c1, which is the third electrode group.If this voltage is set to a value close to 0, the amount of displacement at the stable point of the film-like object 66 can be reduced. It can be made even smaller.

[0020] For example, it is possible to perform microstep driving of about 1/40 of the electrode pitch (420 μm). (E) As shown in FIG. 14, in a microstep drive device for a film-like object, a stator 91 is provided with a plurality of strip electrodes 94 wired within an insulator 92, and a stator 91 is set on the stator 91. A film-like object 100 is provided, and a means for applying low-density positive and negative charges to the surface of the film-like object 100 is provided. Drive at a micro pitch smaller than .

[0021]

Embodiments Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a perspective view of a microstep drive device for a film-like object showing a first embodiment of the present invention;
FIG. 2 is a block diagram of the microstep drive device for the film-like object. As shown in these figures, the lower stator 2
1 has a plurality of strip electrodes 24 embedded in an insulator 22.

More specifically, the stator 21 includes a base layer made of a film-like insulator, a plurality of strip-shaped electrodes 24 wired on the base layer, and a film-like electrode formed on the base layer. and an insulating layer. On the other hand, the film-like object 30 as a mover includes an insulator layer 31 and a low-resistance layer 3.
2, and is placed in contact with the stator 21. Therefore, as will be described later, a voltage is selectively applied to the strip electrode 24 to drive the film-like object 30 and to position it.

Next, one pitch operation of this film-like object micro-positioning device will be explained with reference to FIG. First, as shown in FIG. 3(1), a positive voltage +VO is applied to the electrodes 24a1 and 24a2, which are the first electrode group embedded in the insulator 22 constituting the stator 21, and the electrode 24b1, which is the second electrode group. , 24b2 and 0V are applied to the electrodes 24c1 and 24c2, which are the third electrode group. Then, a current flows in the low-resistance layer 32, where there was no charge at first, and a charge is induced at the boundary between the low-resistance layer 32 and the insulator layer 31, resulting in an equilibrium state. The dashed line drawn on the film-like object 30 represents a mirror image of the electrode.

Next, as shown in FIG. 3(2), the applied voltage pattern is shifted to the right. That is, 0V is applied to the electrodes 24a1 and 24a2 that are the first electrode group, a positive voltage +VO is applied to the electrodes 24b1 and 24b2 that are the second electrode group, and a negative voltage -VO is applied to the electrodes 24c1 and 24c2 that are the third electrode group.
are applied respectively. Then, a rightward force acts on the induced charge within the film-like object 30 in the figure, and it begins to move. Then, the film-like object 30 is dragged by the moving induced charges and begins to move as shown in FIG. 3(3).

In the present invention, since the film-like object 30 has the low-resistance layer 32 and the resistance value of the film-like object 30 is low, the induced charge is transferred to the film-like object 3.
Since the time constant is short, the time that the film-like object 30 can remain at the original position in the electrode 1 is shortened.
Before the film-like object 30 is completely moved by the pitch, the charges within the film-like object 30 disappear. At that point, the film-like object 30 loses its rightward driving force and comes to rest. in this way,
Since the time constant is short, the amount of movement lp has a value much smaller than the electrode pitch. By repeating such operations, minute step driving can be realized.

As described above, in the conventional driving method, the entire film-like object moved along with the induced charge by one electrode pitch, but in this method, since the resistance value of the film-like object is low, the amount of movement is smaller than the electrode pitch. This is a fairly small value, allowing minute step driving. In this case, if the resistance value of the film-like object is too low, the film-like object cannot be driven, but in this method, the resistance value of the film-like object is lowered to near the drivable limit, thereby realizing minute steps.

A specific example of the configuration will be explained below. As shown in FIG. 1, the electrode pitch l5 is 420 μm, the electrode width l6 is 210 μm, and the distance l7 from the electrode to the stator surface (see FIG. 2) is about 170 μm. In order to reduce uncertainties caused by frictional force, hollow glass particles with a diameter of 20 μm were sprinkled on the stator for lubrication. The experiment was conducted by placing a film-like object with a known resistance value on top of it.

The relationship between the surface resistance value of the film-like object and the distance traveled by one step is shown in FIG. Furthermore, it is clear that the smaller the resistance value of the film-like object, the smaller the moving distance. For example, 3.9×10
For 11Ω/□, step 24μm, 2.7×101
For 2Ω/□, step 51μm, 3.6×1012
For Ω/□, step 67μm, 1.2×1013Ω
For /□, step 250μm, 9.8×1013Ω
In the case of /□, the step is 460 μm.

FIG. 5 shows the state when moving one step. As is clear from this figure, when the resistance value of the film-like object is 1011Ω/□, 2
Fine step driving of 0 μm is performed. In this way, it was possible to achieve microstep drive of about 1/20 of the electrode pitch.

FIG. 6 is a perspective view of a microstep drive device for a film-like object showing a second embodiment of the present invention. As shown in these figures, the lower stator 41 has an insulator 4
2 with a plurality of strip electrodes 44 embedded therein. Figure 6
In, the film-like object 50 is a driven object,
Insulating film or paper can be used. In addition, the drive is not limited to plastic films, but can also drive paper, glass, ceramics, etc. as long as they are thin insulators.

[0031] Such a film-like object 50 is attached to the stator 4.
1 so that they are in contact with each other. Further, an ion blower 48 is used as an ion generating device, which is composed of a needle electrode 46 for applying positive and negative charges on the film-like object 50, an AC high voltage source 45 connected thereto, and a blower 47. Note that a thin wire may be used instead of the needle electrode 46 described above. The ion blower 48 imparts high-density positive and negative charges onto the film-like object 50, and a voltage is selectively applied to the strip-like electrode 44, as will be described later, to drive the film-like object 50 and position it. will be held.

Note that the volume resistivity of the ionized air generated by the ion blower 48 is preferably 10 7 to 10 9 Ω·m. Further, although only one needle electrode 46 of the ion blower 48 is shown, the film-like object 46
It is desirable to provide a plurality of them on 0. Next, the operation of this microstep drive device for a film-like object will be explained with reference to FIGS. 7 to 9.

First, as shown in FIG. 7, a film-like object 60 (eg, 10 14 Ω or more) is pretreated. That is, each electrode group 44a1, 44a2, 44a3, 44b1, embedded in the insulator 42 constituting the stator 41,
44b2, 44b3, 44c1, 44c2, 44c
3 is set to 0V, positive and negative charges are applied by the ion blower 48, and if there is any residual charge, it is neutralized to eliminate the charge, and initial settings are performed.

Therefore, the insulator 42 constituting the stator 41
Electrodes 44a1, 4 which are the first electrode group embedded in
A positive voltage +VO is applied to 4a2 and 44a3, and a negative voltage - is applied to electrodes 44b1, 44b2 and 44b3, which are the second electrode group.
VO, electrodes 44c1 and 44c2 which are the third electrode group
, 44c3. In this state, ions are sprinkled onto the film-like object 60 placed on the stator 41 by the ion blower 48 to create a high-density charge pattern along the electrodes.

Next, as shown in FIG. 8, the voltage applied to each electrode is switched. In other words, the voltage is 0V on the electrodes 44a1, 44a2, 44a3, which are the first electrode group, and the voltage on the second electrode group is 0V.
Electrodes 44b1, 44b2, 44b3 which are the electrode group of
A positive voltage +V0 is applied to the electrode 44c1, which is the third electrode group.
, 44c2, and 44c3, a negative voltage -VO is applied to them, respectively. Then, the charge inside each electrode moves instantly, but
The charge on the film-like object 60 is retained because of its high resistance value.

Therefore, the electrodes 44a1, 44b1, 4
Since the charges 4a2 and 44b2 have the same sign as the charges above them, a repulsive force, that is, a force that causes the film-like object 60 to float is generated. However, since the surface of the film-like object 60 is given high-density positive and negative charges, the surface of the film-like object 60 is equivalent to the presence of a low-resistance layer, and the resistance value of the film-like object 60 is Since the induced charge is low, the time that the induced charge can remain at the original position in the film-like object 60 is short (the time constant is short), and the film-like object The charge within 60 disappears. at the time,
The rightward driving force of the film-like object 60 disappears, and the film-like object 60 comes to rest as shown in FIG. In this way, if the time constant is short, the amount of movement will be much smaller than the electrode pitch. By repeating such operations, minute step driving can be realized.

By repeating the above steps, the film-like object 60 can be driven and moved in minute steps. FIG. 10 is a diagram illustrating the operating principle of a microstep drive device for a film-like object showing a third embodiment of the present invention. First, as shown in FIG. 10(1), the electrode 6, which is the first electrode group, is embedded in the insulator 64 that constitutes the stator 63.
Positive voltage +VO to 5a1, electrode 65 which is the second electrode group
Negative voltage -VO on b1, electrode 65c which is the third electrode group
1 and apply 0V to each. Then, the high-resistance layer 68 of the film-like object 66, which initially had no charge,
A current flows inside, and charges are induced at the boundary between the high-resistance layer 68 and the insulator layer 67, resulting in an equilibrium state. That is, when the voltage shown in FIG. 10(1) is applied to each electrode, charges as shown in the figure are induced in the film-like object 66 after a time sufficiently longer than the time constant. At this time, the film-like object 66
The position where is stable is the position where the charge is directly above each electrode. The dashed line drawn on the film-like object 66 represents a mirror image of the electrode.

Next, assuming that the time constant of the film-like object 66 is sufficiently long and the induced charge charged in FIG. 10(1) is fixed on the film-like object 66, as shown in FIG. 10(2), When a voltage is applied, that is, a positive voltage +VO is applied to the electrode 65a1 that is the first electrode group, a negative voltage -VO is applied to the electrode 65b1 that is the second electrode group, and a negative voltage - is applied to the electrode 65c1 that is the third electrode group. The stable point when applying V1 is slightly displaced to the right in the figure compared to the case of FIG. 10(1). The amount of displacement is the rightmost electrode, that is, the third
The amount of displacement of the stable point of the film-like object 66 can be further reduced by setting the voltage to a value close to 0.

By applying a voltage in this manner, the film-like object 66 can be driven in minute steps. In other words, if the stable point is displaced to the right, the film-like object 66 can be driven to the right in minute steps. Furthermore, if the stable point is displaced to the right, a rightward force acts on the film-like object 66, but since the amount of displacement of the stable point is minute, the value is small, and furthermore, the force is small between the film-like object 66 and the stator 63. Since a suction force also acts, it is impossible to overcome the frictional force and move the film-like object 66 to a stable point. This problem can be solved as shown below.

FIG. 11 is an explanatory diagram of the operation of a microstep drive device for a film-like object showing a third embodiment of the present invention. First, as shown in FIG. 11(1), a positive voltage +VO is applied to the electrodes 74a1 and 74a2, which are the first electrode group, embedded in the insulator 72 constituting the stator 71, and the electrode 74b1, which is the second electrode group. , 74b2, and 0V to the electrodes 74c1 and 74c2, which are the third electrode group. Then, a current flows in the high-resistance layer 82, which initially had no charge, and a charge is induced at the boundary between the high-resistance layer 82 and the insulator layer 81, resulting in an equilibrium state. That is, when the voltage shown in FIG. 11(1) is applied to each electrode, charges as shown in the figure are induced in the film-like object 80 after a time sufficiently longer than the time constant. At this time,
The position where the moving body is stable is the position where the charge is directly above each electrode. The dashed line drawn on the film-like object 80 represents a mirror image of the electrode.

Next, after the induction of charges is completed, as shown in FIG.
2) Switch the applied voltage pattern as shown in 2). That is, the negative voltage -VO is applied to the electrodes 74a1 and 74a2 that are the first electrode group, and the electrodes 74b1 and 74b1 are the second electrode group.
Positive voltage +VO to 74b2, electrode 7 which is the third electrode group
A negative voltage -VO is applied to 4c1 and 74c2, respectively. Then, the film-like object 80 is large and almost covers the electrode 1.
Move to the right by a pitch.

Next, as shown in FIG. 11(3), the applied voltage is switched, that is, the electrode 74a of the first electrode group
1, 74a2, negative voltage -VO to the second electrode group, electrodes 74b1, 74b2, negative voltage -V1 to the third electrode group, electrodes 74c1, 74c2.
are applied respectively, and then the film-like object 80 is pulled back. At this point, the stable point has shifted to the right compared to the time shown in FIG. 11(1), so the film-like object 80 is
It comes to rest at a position moved to the right by the amount of displacement of the stable point from position (1). When the film-like object 80 comes to a complete standstill and friction is ensured between it and the stator 71, the process shown in FIG.
), apply the voltage as shown. At this time, the stable point moves to the left, but due to the frictional force, the film-like object 80
While being fixed at the position shown in FIG. 11(3), only the charges within the film-like object 80 move after a sufficient period of time, and charges as shown in FIG. 11(1) are induced. By repeating the above operations, minute step driving is realized.

Here, although the moving target is small, there are two meanings in swinging the film-like object 80 largely from side to side. The first is to move the film-like object 80 by overcoming friction by largely shifting the stable point. Secondly, by shaking it left and right, air enters between the film-like object 80 and the stator 71.
This means that the frictional force becomes smaller. If the frictional force is large, the engine cannot be driven due to this frictional force at the time of starting. Due to the reduced frictional force, the film-like object 80 starts reliably and comes to rest precisely on a stable point.

A specific example of the configuration will be explained below. Here, the same stator as in FIG. 11 was used. The film-like object used had a surface resistance of 7.5×10 13 Ω/□. The experiment was conducted with V0 in FIG. 11 being 750V. The relationship between the applied voltage V1 and the amount of one-step movement in FIG. 11 is as shown in FIG. It can be seen that as the value of the applied voltage V1 approaches 0, the amount of movement becomes smaller. for example,
At 100V, each step is approximately 12μm, at 200V, each step is approximately 37μm, at 300V, each step is approximately 50μm, and at 400V, each step is approximately 63μm.
It became.

[0045] Also, the situation when moving one step is shown in Figure 13.
It became like this. Move the electrode one pitch once, return to the original position, and finally take a minute step lg [Figure 11 (3)
)). In this way, in the third example, by appropriately controlling the voltage applied to the electrodes, it was possible to achieve microstep drive of about 1/40 of the electrode pitch.

It should be noted that fine conductor pattern wiring of strip electrodes on the above-mentioned insulator can be easily done in large quantities by printing technology.
And it can be manufactured at low cost. Next, the fourth aspect of the present invention
An example will be described using FIGS. 14 to 17. Figure 14
FIG. 3 is a perspective view of a microstep drive device for a film-like object showing a fourth embodiment of the present invention.

As shown in these figures, the lower stator 9
1 has a plurality of strip electrodes 94 embedded in an insulator 92. The film-like object 100 is an object to be driven, and may be an insulating film or paper. Such a film-like object 100 is set on and in contact with the stator 91. Further, on the film-like object 100, there is a needle electrode 96 for applying positive and negative charges, and an AC high voltage source 95 (for example, 7 to 10 KV) connected thereto.
An ion blower 98 (corona discharge type static eliminator: for example, Aerostat A-80 model manufactured by Simco Japan Co., Ltd.) is used as an ion generator comprising a blower 97. The ion blower 98 applies positive and negative charges to the film-like object 100, and a voltage is selectively applied to the strip-shaped electrode 94 as described later.
At the same time as driving, positioning is performed.

Note that the volume resistivity of the ionized air generated by the ion blower 98 is preferably 1010 to 1012 Ω·m. Further, although only one needle electrode 96 of the ion blower 98 is shown, the film-like object 1
It is desirable to provide a plurality of them on 00. Next, the operation of this microstep drive device for a film-like object will be explained using FIGS. 15 to 17. First, as shown in FIG. 15, a film-like object 110 (eg, 10<14 >Ω or more) is pretreated. That is, each electrode group 94a1, 94a2 embedded in the insulator 92 constituting the stator 91
,94a3,94b1 ,94b2 ,94b3,94
With c1, 94c2, and 94c3 set to 0V, positive and negative charges are applied by the ion blower 98, and if there is any residual charge, this is neutralized to eliminate the charge, and initial settings are performed.

Therefore, the insulator 92 constituting the stator 91
Electrodes 94a1, 9 which are the first electrode group embedded in
A positive voltage +VO is applied to 4a2 and 94a3, and a negative voltage - is applied to electrodes 94b1, 94b2 and 94b3, which are the second electrode group.
VO, electrodes 94c1 and 94c2 which are the third electrode group
, 94c3. In this state, ions are sprinkled onto the film-like object 100 placed on the stator 91 by the ion blower 98 to create a charge pattern along the electrodes.

Next, as shown in FIG. 16, the voltage applied to each electrode is switched. In other words, the negative voltage -VO
, electrodes 94b1, 94b2, which are the second electrode group,
Positive voltage +VO to 94b3, electrode 9 which is the third electrode group
A negative voltage -VO is applied to 4c1, 94c2, and 94c3, respectively. Then, the charges in each electrode move instantaneously, but the charges in the film-like object 110 are retained because of its high resistance value.

Therefore, the electrodes 94a1, 94b1, 9
Since the charges 4a2 and 94b2 have the same sign as the charges above them, a repulsive force, that is, a force that causes the film-like object 110 to float is generated. Next, as shown in FIG. 17, the applied voltage is switched. That is, electrode 9 which is the first electrode group
Positive voltage +VO to 4a1, 94a2, 94a3, second
A negative voltage -VO is applied to the electrodes 74b1, 74b2, 74b3 which are the third electrode group, and the electrodes 74c1, 7 which are the third electrode group.
Apply negative voltage -V1 to 4c2 and 74c3, respectively,
This time, the film-like object 110 is pulled back. At this point, the stable point has moved to the right compared to the time shown in FIG. 15, so the film-like object 110 comes to rest at a position moved to the right by the amount of displacement of the stable point from the position shown in FIG. When the film-like object 110 comes to a complete standstill and friction is ensured between it and the stator 91, voltage is applied again as shown in FIG. 15. At this time, the stable point moves to the left, but the film-like object 110 remains fixed at the position shown in FIG. A charge as shown in 15 is induced. By repeating the above operations, minute step driving is realized.

With this configuration, it is possible to drive the film-like object in minute steps similar to that shown in FIG. 12, and it is possible to perform the same operation as shown in FIG. 13. Also,
The present invention is not limited to the above embodiments, and various modifications can be made based on the spirit of the present invention, and these are not excluded from the scope of the present invention.

[0053]

As described above in detail, according to the present invention, fine pitch drive smaller than the electrode pitch can be achieved despite the simple configuration. That is, by setting the resistance value of the film-like object to be small, it is possible to perform fine step driving of, for example, about 1/20 of the electrode pitch. Furthermore, by appropriately controlling the voltage applied to the electrodes, it was possible to achieve microstep drive of about 1/40 of the electrode pitch.

Further, by applying positive and negative charges to a film-like object such as an insulating film or paper, it is possible to perform minute step driving similar to the above. Therefore, it becomes possible to perform minute paper feeding for high-quality printing in printers and facsimile machines, and minute step drive when printing on films, fabrics, etc., and the effects brought about by the present invention are significant.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a microstep drive device for a film-like object showing a first embodiment of the present invention.

FIG. 2 is a configuration diagram of a microstep drive device for a film-like object showing a first embodiment of the present invention.

FIG. 3 is an explanatory diagram of the operation of the microstep drive device for a film-like object showing the first embodiment of the present invention.

FIG. 4 is a diagram showing the relationship between the one-step movement amount and the resistance value of the film-like object according to the first embodiment of the present invention.

FIG. 5 is a diagram illustrating microstep driving using a low resistance value of the microstep driving device for a film-like object according to the first embodiment of the present invention.

FIG. 6 is a perspective view of a microstep drive device for a film-like object showing a second embodiment of the present invention.

FIG. 7 is a diagram showing a first operation of a microstep drive device for a film-like object according to a second embodiment of the present invention.

FIG. 8 is a diagram illustrating a second operation of a microstep drive device for a film-like object according to a second embodiment of the present invention.

FIG. 9 is a diagram illustrating a third operation of the microstep drive device for a film-like object according to the second embodiment of the present invention.

FIG. 10 is a diagram illustrating the operating principle of a microstep drive device for a film-like object showing a third embodiment of the present invention.

FIG. 11 is an explanatory diagram of the operation of a microstep drive device for a film-like object showing a third embodiment of the present invention.

FIG. 12: Applied voltages V1 and 1 in the third embodiment of the present invention
FIG. 3 is a diagram showing a relationship between step movement amounts.

FIG. 13 is a diagram showing microstep driving by controlling voltage in a third embodiment of the present invention.

FIG. 14 is a perspective view of a microstep drive device for a film-like object showing a fourth embodiment of the present invention.

FIG. 15 is a diagram illustrating a first operation of a microstep drive device for a film-like object according to a fourth embodiment of the present invention.

FIG. 16 is a diagram showing a second operation of the microstep drive device for a film-like object according to the fourth embodiment of the present invention.

FIG. 17 is a diagram showing a third operation of the microstep drive device for a film-like object according to the fourth embodiment of the present invention.

FIG. 18 is a perspective view of an electrostatic actuator using a conventional film.

FIG. 19 is a configuration diagram of an electrostatic actuator using a conventional film.

FIG. 20 is an explanatory diagram of one-pitch operation of an electrostatic actuator using a conventional film.

[Explanation of symbols]

21, 41, 63, 71, 91 Stator 22, 4
2, 64, 72, 92 Insulator 24, 44, 65
, 74, 94 Strip electrode 30, 50, 60, 66
, 80, 100, 110 Film-like object 31, 67, 81 Insulator layer 32 Low resistance layer 24a1, 24a2, 44a1, 44a2, 44
a3, 65a1, 74a1, 74a2, 94a1, 94a2, 94a3 First electrode 24b1
, 24b2, 44b1 , 44b2 , 44b3, 65
b1, 74b1, 74b2, 94b1, 94b2, 94b3 Second electrode 24c1
,24c2,44c1 ,44c2 ,44c3,65
c1, 74c1, 74c2, 94c1, 94c2, 94c3 Third electrode 45, 95
AC high voltage source 46, 96 Needle electrode 47, 97 Air blower 48, 98 Ion blower 68, 82 High resistance layer

Claims (14)

[Claims] Claim 1: (a) a stator comprising a plurality of strip-shaped electrodes wired within an insulator; (b) a film set on the stator and comprising a film-like insulator layer and a low-resistance layer; (c
) a means for driving the film-like object at a minute pitch smaller than the pitch of the strip-like electrodes by switching a voltage to the strip-like electrodes. 2. In the microstep device for a film-like object according to claim 1, the surface resistance value of the low resistance layer is 10.
A microstep drive device for a film-like object having a resistance of 11 to 1014 Ω/□. 3. (a) a stator comprising a plurality of strip electrodes wired within an insulator; (b) a film-like object set on the stator;
c) means for applying high-density positive and negative charges to the surface of the film-like object, and (d) means for applying high-density positive and negative charges to the surface of the film-like object. 1. A microstep driving device for a film-like object, comprising: means for driving a film-like object. 4. The microstep drive device for a film-like object according to claim 3, wherein the film-like object is an insulating film or paper having a surface resistance of 10 14 Ω/□ or more. 5. A micro-sized film-like object in which a film-like object is set on a stator having a plurality of band-like electrodes wired inside an insulator, and the film-like object is driven by switching the voltage to the band-like electrodes. In the step driving method, (a) the electrical resistance of the surface of the film-like object is set low, and (b) the voltage to the strip-shaped electrodes is switched to drive the film-like object at a minute pitch smaller than the pitch of the strip-shaped electrodes. micro step driving method. 6. The method for driving a film-like object in minute steps according to claim 5, wherein the minute pitch is about 1/20 of the electrode pitch. 7. (a) a stator comprising a plurality of strip electrodes wired within an insulator; (b) a film set on the stator and comprising a film-like insulator layer and a high-resistance layer; (c
) A microstep drive device for a film-like object, comprising means for driving the film-like object at a minute pitch smaller than the pitch of the strip-like electrodes by switching a voltage to the strip-like electrodes. 8. (a) a stator comprising a plurality of strip electrodes wired within an insulator; (b) a film-like object set on the stator;
c) providing means for applying low-density positive and negative charges to the surface of the film-like object, and (d) switching the voltage to the strip-like electrodes to move the film-like object at a minute pitch smaller than the pitch of the strip-like electrodes. 1. A microstep driving device for a film-like object, comprising: means for driving a film-like object. 9. The microstep drive device for a film-like object according to claim 8, wherein the film-like object is an insulating film or paper made of a material with a high surface resistance. 10. A film-like object is set on a stator having a plurality of band-like electrodes wired inside an insulator, and the film-like object is driven by switching the voltage to the band-like electrodes. In the step driving method, (a) the electrical resistance of the surface of the film-like object is set high, and (b) the voltage to the strip-like electrodes is switched to drive the film-like object at a minute pitch smaller than the pitch of the strip-like electrodes. micro step driving method. 11. The microstep driving method for a film-like object according to claim 10, wherein the step (b) includes (a) setting the first strip electrode to the first potential and setting the second strip electrode to the second potential. (b) Next, the first strip electrode is set to the second potential, the second strip electrode is set to the first potential, and the third strip electrode is set to the third potential. After setting the three strip-shaped electrodes to the second potential and driving the film-shaped object, (
c) Set the first strip electrode to the first potential, the second strip electrode to the second potential, and the third strip electrode to the fourth potential, move by the electrode pitch, and then pull back. A microstep driving method for a film-like object that performs microstep driving. 12. The microstep driving method for a film-like object according to claim 11, wherein the first potential is set to a positive voltage +VO, the second potential is set to a negative voltage -VO, and the third potential is set to 0V. After driving the film-like object, the first potential is set to a positive voltage +VO, the second potential is set to a negative voltage -VO, and the fourth potential is set to a negative voltage -V1. Driving method. 13. The method for driving a film-like object in minute steps according to claim 12, wherein the VO 2 is set at 750V.
, a method for driving a film-like object in minute steps, in which the voltage V1 is set to 50V to 400V. 14. The method for driving a film-like object in minute steps according to claim 13, wherein the minute pitch is about 1/40 of the electrode pitch.