JPH0226711Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an electrostatic adsorption device that uses an electrostatic field to adsorb and hold a sheet-like member such as paper on a mounting surface.

[Conventional technology]

Tokukosho is a device that sucks paper onto the mounting surface.
BACKGROUND OF THE INVENTION Vacuum tables utilizing suction force, which are disclosed in Japanese Patent No. 52-44265 and others, are conventionally known. Further, an electrostatic adsorption plate that holds paper on a mounting surface using an electrostatic field is conventionally known.

The vacuum table mentioned above requires a large-capacity pump to apply vacuum force to the entire area of the vacuum surface, so it is divided into multiple small vacuum chambers by partition walls, and the small vacuum chamber is selected according to the size of the paper. Vacuum force is applied to the paper.

[Problem that the invention attempts to solve]

In the area switching of the vacuum table described above, it is necessary to suction only a certain area of the paper, and if other parts are suctioned, the suction force is lost and the suction force is reduced. Therefore, if the paper is covering part of an area, the suction power of the suction device will decrease if that area is operated as suction, and if the area is not operated, part of the paper will be suctioned. Therefore, the paper cannot be firmly fixed on the mounting surface. In addition, conventional electrostatic adsorption plates generate an electrostatic field over the entire area of the mounting surface, resulting in large power consumption and being uneconomical.

The present invention aims to eliminate the defects in both the vacuum table and the electrostatic chuck plate.

[Means to solve problems]

In order to achieve the above object, the present invention divides the mounting surface into a plurality of areas, arranges a suction device consisting of an electrode for generating an electrostatic field in each of the areas, and selects a desired suction device from among the suction devices. An area switching device is provided for selectively operating the area.

[Effect]

In the above configuration, if the paper covers a part of one of the multiple areas on the loading surface, by operating that area, the entire area of the paper can be loaded without reducing the suction force. It can be adsorbed onto the surface.

〔Example〕

The configuration of the present invention will be described below with reference to embodiments shown in the accompanying drawings.

Reference numeral 2 denotes an insulating plate, and on its upper surface there is a positive electrode 4a made of a strip-shaped copper plate, and a negative electrode 4b.
is fixed within a predetermined area A. The electrodes 4a and 4b constitute a first adsorption device 4.
With a similar configuration, a second suction device 6 is fixedly installed in area B on the insulating plate 2, and a third suction device is fixedly installed in area C. A top plate (not shown) made of a plate-shaped insulating material is fixed onto the insulating plate 2, and the surface of the top plate constitutes a placement surface on which paper or the like is placed.

Next, the area switching device will be explained with reference to FIGS. 2 and 3.

Reference numerals 10, 12, and 14 indicate changeover switches, which are provided corresponding to the suction devices 4, 6, and 8, respectively. 16 is a chattering prevention circuit, 18,
20 is an OR circuit, 22, 24 are monostable multivibrators, 26, 28 are delay circuits, 30, 32 are AND circuits, 34 is an amplifier circuit, 36, 38, 40
is a DC converter.

Next, the operation of the present invention will be explained.

When the switches 10, 12, and 14 are in the off state, when the switch 10 is turned on, the suction device 4 is
Voltage is supplied from the DC converter 36, and the electrode 4
The electrode 4a is charged with a positive charge, and the electrode 4b is charged with a negative charge, so that an electrostatic field for attracting the paper is generated on the area A. When the switch 12 is turned on while the switches 10, 12, and 14 are off, the electrical signal of this switch is sent to the OR gate 1.
8 and 20, and the adsorption device operates first.
On the other hand, in response to a signal from the switch 12 being turned on, the monostable multivibrator 22 outputs a zero signal for a predetermined period of time, and the AND circuit 30 is cut off. When a short time elapses after the monostable multivibrator 30 outputs zero, a "1" signal from the switch is supplied to one input terminal of the AND circuit 30. When the output of the monostable multivibrator 22 returns to "1" after a predetermined period of time has elapsed, the AND circuit 30 outputs an electrical signal of "1" and the adsorption device 6 operates. Switches 10 and 1 are operated on the same principle as above.
2 and 14 are off, when the switch 14 is turned on, the suction device 4 operates to generate suction force in area A, and after a predetermined delay, the suction device 6 operates to generate suction force in area B. Finally, after a predetermined time delay, the suction device 8 operates and electrostatic suction force is generated in area C. In this way, by generating suction force in a waveform in the order of area ABC, when a large sheet of paper that spans all of area ABC is attracted to the placement surface, air is pushed out from the bottom surface of the sheet, and the air is Prevents it from accumulating.

〔effect〕

As mentioned above, the present invention can select an area on the placement surface according to the size of the paper and apply suction force only to the selected area, so it is possible to save power consumption and to select Even if the paper is piled up in a part of the area, the paper can be sucked by the suction device in that area without reducing the suction force unlike the vacuum table.

[Brief explanation of drawings]

The figures show a preferred embodiment of the present invention; FIG. 1 is a plan view, FIG. 2 is a schematic block electronic circuit diagram of the area switching means, and FIG. 3 is an electronic circuit diagram thereof. 2... Insulating plate, 4a, 4b... Electrode, 4, 6,
8... Adsorption device, 10, 12, 14... Changeover switch, 16... Chattering prevention circuit, 18, 2
0...OR circuit, 22,24...monostable multivibrator, 26,28...delay circuit, 30,3
2...AND circuit, 34...Amplification circuit, 36,3
8,40...DC converter.

Claims (1)

[Scope of utility model registration request] A mounting surface is divided into a plurality of areas, each of which is provided with a suction device consisting of an electrode for generating an electrostatic field, and an area for selectively operating a desired suction device among the suction devices. An electrostatic adsorption device characterized by being provided with a switching device.