JPH0611996Y2 - Electrostatic adsorption device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to an electrostatic adsorption device, particularly an electrostatic adsorption device used for a recording paper holding device such as a recording instrument.

(Prior Art) Conventionally, a known electrostatic adsorption device is provided with a pair of comb-teeth pattern electrodes on an upper surface of an insulating substrate, a DC voltage is applied between the electrodes, and static electricity generated by the electrodes causes an object such as paper to be covered. It is designed to adsorb the adsorbate.

(Problems to be Solved by the Invention) However, in such a known device, it has been recognized that the electric charge generated on the surface of the adsorption plate is hard to disappear at a low temperature and the adsorption force thereof is reduced. Therefore, a very high voltage has to be applied in order to maintain the required adsorption force at low temperature.

As an electrostatic chucking device that has attempted to solve such problems, there is one disclosed in Japanese Patent Publication No. 52-34463. In this electrostatic adsorption device, in order to keep the adsorption force at a low temperature at a sufficient value, only a relative voltage is applied without passing a current between the electrodes, and a switch that is turned off during adsorption and turned on during non-adsorption The voltage dividing circuit composed of a resistor allows the power source to absorb the electric charge generated on the surface of the adsorption plate, thereby reducing the influence of the residual electric charge even at a low temperature at which the residual electric charge does not easily disappear.

However, even with this known device, the problem of a decrease in adsorption force due to a decrease in ambient temperature has not yet been solved.

The object of the present invention is to eliminate the above-mentioned problems, so that even when the ambient temperature is lowered, it is possible to maintain a sufficient attracting force without increasing the voltage, and moreover, electrostatic attraction without causing the problem of residual charge. To provide a device.

(Means for Solving Problems) The present invention is directed to a pair of electrodes embedded in a suction plate in a planar shape in a mutually insulated state, and a voltage is applied between the pair of electrodes to generate an electrostatic field. In an electrostatic attraction device including a voltage applying means for generating and attracting an object to be attracted to the attraction plate,
A feature is provided in which one or both electrodes of the pair of electrodes are respectively provided with a current.

(Operation) As described above, the electrostatic adsorption device of the present invention excites an electrostatic field between a pair of electrodes arranged in a planar state in an insulated state to excite an electrostatic field between the electrodes. In addition to providing the adsorption function, the resistance of the electrode described above is used to cause a current to flow through one or both of the electrodes to cause the electrode to generate heat and have a heater function.

Since the electrodes have the heater function as described above, the temperature of the suction plate can be maintained at a certain temperature or more by appropriately selecting the applied voltage even when the outside air temperature becomes low. Therefore, the residual charge is easily erased, so that the attraction force is not reduced, and it is not necessary to consider the influence of the residual charge. Furthermore, as a result of this, the applied voltage can be made relatively low.

(Example) Below, one Example of this invention is described based on drawing.

In FIG. 1, 1 is an adsorption plate, 2a and 2b are a pair of electrodes embedded in the adsorption plate 1 and meandering in a state of keeping a constant interval (meaner shape),
Reference numeral 3 denotes a DC power source, and 4 denotes a high voltage generation circuit for boosting a DC voltage supplied from the DC power source 3, respectively.

In the adsorption plate 1, electrodes 2a and 2b are arranged on the upper surface of a laminated body in which an insulating layer 6 made of an insulating material is adhered on the upper surface of a conductive substrate 5, and an insulating layer is formed so as to cover these electrodes 2a and 2b. An insulating material layer 7 is attached to the upper surface of the insulating layer 6. The surface of the insulating material layer 7 in contact with the object to be adsorbed is made smooth so that the object to be adsorbed is easily adsorbed. The electrodes 2a and 2b are connected to the output ends e and f of the high voltage generating circuit 4 via the wirings 8 and 9 respectively at their one ends a and c, respectively, so that the electrostatic attraction force is sufficiently generated from the high voltage generating circuit 4. Electric charges are applied.

The output terminals i and j of the DC power supply 3 are connected to the input terminals g and h of the high voltage generating circuit 4 via wirings 10 and 11, respectively, so that a DC voltage can be supplied to the high voltage generating circuit 4.
The output terminals i and j of the DC power supply 3 are connected to both ends a and b of the electrode 2b via wirings 12 and 13, respectively, and
Therefore, a DC voltage can be applied to the electrode 2b.
Note that FIG. 1 (B) is shown in an enlarged manner in the thickness direction for clarity of explanation.

To explain the operation of the apparatus configured as described above, first,
A relatively low required voltage supplied from the power source 3 is boosted to a relatively high voltage, for example, about 1500 V by the high voltage generation circuit 4, and applied between the pair of electrodes 2a and 2b. By applying this high voltage, an electrostatic field is generated between the electrodes 2a and 2b, and this electrostatic field attracts and holds an object to be attracted arranged on the electrode side of the attracting plate 1, such as recording paper. To be done.

On the other hand, the DC power supply 3 applies a required voltage to the electrode 2b to generate a required temperature. The voltage applied for this heating varies depending on the setting of the temperature conditions. For example, in order to maintain the temperature of the adsorption plate 1 at 10 ° C or higher in an atmosphere where the temperature is 5 ° C or higher, 12
It is preferable to apply a relatively low voltage such as V and a current of about 2.3A. By the way, the reason why the temperature of the adsorption plate 1 is set to 10 ° C. or higher is that the adsorption force of the adsorption plate 1 is drastically reduced when the temperature is 10 ° C. or lower. Because it is enough.

In this way, the electrode 2b to which the required voltage is applied flows a current determined by its inherent resistance value, heats up to the required temperature, and the electrostatic attraction force of the attraction plate 1 can be always kept constant.

Although one embodiment of the present invention has been described above, the present invention is not limited to the above embodiment, and various modifications can be made.

For example, in order to properly control the temperature of the suction plate 1, a temperature detection sensor is provided on the suction plate 1, and an electrode 2b is provided by an external temperature control device based on the output from the temperature detection sensor.
You may make it control the voltage applied to both ends a and b.

Further, the electrode shape may be a comb tooth shape, a spiral shape or the like in addition to the above-mentioned meander shape. In short, it suffices that a current can be passed through the electrode and that the electrode functions as a heater. Further, in the above-mentioned embodiment, the current is passed through one of the electrodes 2b, but it is also possible to pass a current through both of the electrodes 2a, 2b to generate heat. In this case, a voltage difference sufficient to generate an electrostatic attraction force is generated between both electrodes.

(Effect of the Invention) As apparent from the above description, in the present invention,
By applying a high voltage between a pair of electrodes on one side to generate an electrostatic attraction force between these electrodes, while flowing a current through the electrodes on the other side to generate heat, it is not affected by temperature fluctuations. In addition, the electrostatic attraction force can always be kept constant. Moreover, because of the simple structure, the cost can be kept low, which is extremely useful in industry.

[Brief description of drawings]

1 (A) and 1 (B) are a plan view and a cross-sectional view taken along the line II ', respectively, showing the device of the present invention. DESCRIPTION OF SYMBOLS 1 ... Adsorption plate, 2a, 2b ... Electrode 3 ... DC power supply, 4 ... High voltage generating circuit 5 ... Substrate, 6 ... Insulating layer 7 ... Insulating material layer, 8, 9, 10, 11, 12, 13 ... Wiring

Claims (1)

[Scope of utility model registration request] 1. A pair of electrodes which are embedded in a suction plate in a planar shape in a mutually insulated state, and a voltage is applied between the pair of electrodes to generate an electrostatic field to attract an object to be attracted. An electrostatic adsorption device comprising: a voltage application unit for adsorbing the electric current to each of the pair of electrodes, wherein an electric current is applied to one or both electrodes of the pair of electrodes.