JPH0487581A - Electrostatical attracting and holding device - Google Patents

Abstract

PURPOSE:To have enough attractive tenacity with simple constitution by attracting a sheet member to an electrostatically attracting plate by the unequal electric fiele by a charge pattern. CONSTITUTION:Pushing a charge pattern generator 2 against an electrostatically sucking plate 1, and grasping a lever switch 10, and applying the AC high voltage of f in frequency, and pulling up the charge pattern generator 2 at a speed of v, a roller electrode 9 makes a positive or negative charge pattern of l in pitch on a dielectric 8. For the pitch R of this charge pattern, the AC voltage application frequency f, an the pulling-down speed, the relation of l=v/f materializes.When a sheet member 6 is placed on this charge pattern made, it generates siction force electrostatically, and can hold the sheet member. That is, an electric field stronger than other exists on the boundary between the positively charged region and the negatively charged region on the dielectric 8, and by the unequal electric field generated at each margin of this charge pattern, the sheed member 6 can be attracted strongly.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an electrostatic adsorption/holding device for adsorbing and holding a sheet on a bulletin board, drawing board, etc. using an uneven electric field.

[Conventional technology]

When displaying sheet members such as documents, drawings, paintings, photographs, OHP sheets, etc. on a bulletin board, rivets, tape, adhesives, etc. are used for boat fishing.

However, these fixing methods end up staining or damaging the front or back surface of the sheet member.

As a method of holding the sheet member on a bulletin board, etc. without staining or scratching it, the sheet member is held by sandwiching it between magnetic materials, or by making a small hole in the bulletin board and suctioning it from the back. However, when using a magnetic material to sandwich the sheet, it has the disadvantage of covering part of the sheet member, and when using the suction method, the suction pump must be constantly operated, making the device bulky. It has the disadvantage of becoming.

On the other hand, some devices that utilize static electricity have relatively simple structures and can be implemented.

Techniques for adhering sheet members to plywood using static electricity are disclosed in Japanese Patent Publications No. 58-18239 and Japanese Patent Publication No. 58-5.
Known examples include Japanese Utility Model Publication No. 5757, Japanese Utility Model Publication No. 58-6712, and Japanese Utility Model Application Publication No. 59-35098.

[Problem to be solved by the invention]

However, among the above techniques, the techniques disclosed in Japanese Utility Model Publication No. 58-6712 and Japanese Utility Model Application Publication No. 59-35098 do not use electrostatic adsorption by applying high voltage from an external power source, and therefore, although they have a simple structure, they do not require electrostatic adsorption. The drawback was that the holding power was weak.

Furthermore, in the technique disclosed in Japanese Patent Publication No. 58-18239, an external power supply applies direct current to uniformly charge the sheet on which the drawing is placed, thereby attracting the drawing paper.
Because it has a charge with the opposite polarity to the charge required to attract it onto the paper, the attraction force becomes slightly weaker. On the other hand, in Japanese Patent Publication No. 58-55757, the adsorption force is increased by releasing the charge of opposite polarity to the charge for adsorbing the sheet, which obstructs the adsorption, but the sheet becomes charged. , there is a problem that when removed from the bulletin board, it will stick to other grounded parts.
A special means was required to eliminate static electricity.

On the other hand, Japanese Patent Publication No. 57-58872 discloses a technique for obtaining sufficient adsorption and holding force using an unequal electric field, but this conventional example has the disadvantage that the structure is complicated because the electrodes are comb-shaped. was there.

The present invention has been made based on the above-mentioned background, and is based on an electrostatic adsorption/holding device that utilizes unequal electric fields, has a simple structure, has sufficient adsorption/holding force, and is capable of holding sheets from bulletin boards, etc. It is an object of the present invention to provide an electrostatic adsorption holding device that does not require static electricity removal after peeling off.

[Means to solve the problem]

The above object includes an electrostatic chuck plate made of a plate-shaped conductor and a dielectric covering the conductor, and a charge pattern generating means for forming a charge pattern by applying a high voltage on the surface of the electrostatic chuck plate, This is achieved by a first means of attracting the sheet member to the electrostatic attraction plate using an unequal electric field caused by the charge pattern.

In the first means, the charge pattern generating means generates a positive and negative charge pattern on the electrostatic chuck plate when an AC high voltage is applied thereto and the electrostatic chuck plate is moved in contact with the charge pattern generating means. This is achieved by a second means consisting of forming roller electrodes.

Further, the above object is also achieved by a third means in which the conductor is made of a flexible material in the first means.

[Effect]

According to the first means, a charge pattern is formed on the electrostatic attraction plate by the charge pattern generating means, and the sheet member is attracted to the electrostatic attraction plate with sufficient attraction force by the unequal electric field of this charge pattern, Moreover, the sheet member is not charged with an electrostatic charge after being peeled off.

According to the second means, the roller electrode applies a positive and negative charge pattern of a highly unequal electric field to the electrostatic attraction plate by applying alternating current while rotating along the electrostatic attraction plate.

According to the third means, by composing the conductor with a flexible material, the suction plate itself is also flexible, and it can be rolled up or
Make it possible to bend it.

〔Example〕

Embodiments of the present invention will be described below based on the drawings.

FIG. 1 is a perspective view of an electrostatic adsorption holding device according to an embodiment of the present invention, where l is an electrostatic adsorption plate, and 2 is a charge pattern generator that forms a positive and negative charge pattern on this electrostatic adsorption plate. ,3
is an AC applied voltage generator that applies high-voltage AC voltage to the charge pattern generator 2; 4 is a main switch used to turn on and off the device; 5 is a commercial power source (for example, AClooV
), and 6 is a sheet member that is electrostatically attracted and held by the electrostatic attraction plate 1 .

FIG. 2 is a cross-sectional view of the entire structure of the electrostatic chuck plate 1. The electrostatic chuck plate 1 is composed of a plate-shaped conductive material 7 and a dielectric material 8 covering the outer surface of the conductive material 7. As shown in FIG. The dielectric 8 is made of Mylar (trade name) with a thickness of 75 μm in this example, but the material is not limited to Mylar, and any insulating dielectric such as polyester may be used, and the thinner the material, the better the material for adsorption. The AC applied voltage level for forming the charge pattern can be lowered, but if it is too high, leakage will occur on the roller electrode and conductor 7, which will be described later, due to scratches on the dielectric. Requires appropriate thickness. Furthermore, by covering both sides of the conductor 7 with a dielectric 8 as shown in FIG. 2, the back surface can also be used as an electrostatic adsorption plate.

The charge pattern generator 2 is composed of a roller electrode 9 and a lever switch IO. 11 is an AC high voltage power supply;
The conductor 7 serves as a ground for this AC high voltage power supply 11, and faces the roller electrode 9 to which an AC high voltage is applied. This conductor 7 is plate-shaped, but if it is made of a sufficiently thin and flexible material, the electrostatic adsorption plate 1 can be rolled up or bent to make it easier to carry and to reduce the storage space. .

FIG. 3 is a perspective view of the charge pattern generator 2. FIG.

After turning on the main switch 4 of the device, by grasping the lever switch 10, the AC high voltage applied to the Coke electric fi9 can be turned on and off.

Further, it goes without saying that the roller electrode 9, the grip portion 2a, and the case portion 2b are completely insulated.

Next, the principle of adsorption of a sheet member by a charge pattern will be explained with reference to FIG. As shown in the figure, press the charge pattern generator 2 against the clamping plate 1, hold the lever switch 10, apply an AC high voltage with a frequency f, and move the charge pattern generator 2 at a speed V from the dotted line to the solid line. When the roller electrode 9 is pulled down as shown in , a positive and negative charge pattern with a pitch l is created on the dielectric 8 while rotating together.

The charge pattern pitch l, the AC voltage application frequency f, and the lowering speed V have the following relationship: It = v / f - (l).

When the sheet member 6 is placed on the created charge pattern, an electrostatic adsorption force is generated to hold the sheet member.

That is, a stronger electric field exists at the boundary between the positively charged area and the negatively charged area on the dielectric 8, and the sheet member 6 can be strongly adsorbed.

Although this is different in structure from a sheet holding system using comb-shaped electric scratching pads that is often used in pen plotters, the principle is similar.

Experimental data regarding the adsorption force of the sheet member 6 of this device revealed that the adsorption force differs depending on the charge pattern pitch l under a constant AC high voltage level.

Figure 5 shows the experimental data. In this case, the adsorption force with respect to the pitch l is shown assuming that the AC high voltage application level is 3 (kV). According to this, it can be seen that the maximum adsorption force is obtained when the pitch l is 3 cranes.

Pitch l is 3fl, power supply is AClooV, 50H
Since it is performed at z or 60Hz, for example, 50) 1
If this power supply voltage is boosted as z, the AC high voltage power supply will have a simple configuration.
is v = f l1 = 50 (Hz) x 3 (wm)
= 150 (Tsuru/s), and it can be seen that the maximum adsorption force can be obtained by pulling down at this speed.

In general, the suction force for suctioning and holding the sheet member 6 is related to the material and weight of the sheet member 6, but it has been found from experimental results that a suction force of 1 kgf or more can sufficiently hold the sheet member 6.

Furthermore, leakage of charges on the dielectric 8 depends on the material of the dielectric 8, but in this embodiment, it takes several tens to several hundreds of days, so it is at a level that does not pose a practical problem. In this embodiment, the AC high voltage waveform is a sinusoidal waveform, but it may be a square waveform.

〔Effect of the invention〕

As explained above, according to the invention set forth in claim 1, by using the unequal electric field, the sheet member can be reliably attracted and held on the electrostatic adsorption plate, and the sheet member can be held by the electrostatic adsorption plate. It is possible to prevent adsorption to other members when peeled off from the adsorption plate.

Further, according to the invention as set forth in claim 2, since a positive and negative charge pattern is generated by applying alternating current, the unequal electric field is high, leading to an increase in the attraction force.

Furthermore, since the electrode is a roller, alternating current voltage is applied while rotating with the electrode, so there is no damage to the dielectric material.

Furthermore, according to the third aspect of the present invention, the conductor is made of a flexible material, so that it can be rolled or bent to make it easier to carry and to reduce the storage space.

[Brief explanation of drawings]

FIG. 1 is a perspective view of an electrostatic adsorption holding device according to an embodiment of the present invention, FIG. 2 is a vertical cross-sectional configuration diagram of the same main part, FIG. 3 is a perspective view of a charge pattern generator, and FIG. 4 is a charge pattern generator. FIG. 5, which is an explanatory diagram of the principle of attraction of a sheet member by a pattern, is a characteristic diagram showing the relationship between charge pattern pitch and attraction force. 1... Electrostatic adsorption plate, 2... Charge pattern generator, 3
-... AC applied voltage generator, 7... Conductor, 8...
Dielectric material, 9...roller electrode. Part 1, Figure 3

Claims (3)

[Claims] (1) An electrostatic chuck plate made of a plate-shaped conductor and a dielectric covering the conductor, and a charge pattern generating means for forming a charge pattern by applying a high voltage on the surface of the electrostatic chuck plate; An electrostatic attraction holding device characterized in that the sheet member is attracted to the electrostatic attraction plate by an unequal electric field generated by a charge pattern. (2) In claim 1, the charge pattern generating means forms a positive and negative charge pattern on the electrostatic chuck plate when an AC high voltage is applied thereto and the charge pattern generation means is moved in contact with the electrostatic chuck plate. An electrostatic adsorption holding device characterized by comprising a roller electrode. (3) The electrostatic adsorption/holding device according to claim 1, wherein the conductor is made of a flexible material.