JPS6083049A - Electronic photograph recording device - Google Patents

Abstract

PURPOSE:To contrive continuation of good corona discharge even in change of humidity and enable stable charge, transfer, separation and destaticization by controlling the applied voltage to a corona discharger responding to outputs of a humidity sensor provided near a photosensitive body. CONSTITUTION:A voltage higher than the corona starting voltage corresponding to absolute humidity is applied by a power source 5 to a discharge electrode wire 1. Consequently, corona discharge is caused between the discharge electrode wire 1 and paired electrodes 11, and charge is formed on a charged body 10, i.e. a photosensitive body, and the potential of the photosensitive body becomes a certain charge potential. A voltage of the polarity equal to the discharge electrode wire 1, several hundreds volt, is applied from a power source 3. In the case where absolute humidity near the photosensitive body becomes high, the corona starting voltage also becomes higher. However, resistance of a humidity sensor 8 also increases, and the voltage applied to the discharge electrode wire 1 becomes higher, and corona discharge is maintained. Even when absolute humidity becomes low, the voltage applied to the discharge electrode wire 1 also becomes low, and discharge becomes whole path destruction, and generation of spark discharge can be prevented.

Description

[Detailed description of the invention] The present invention relates to an electrophotographic recording device.

°The electrophotographic method generally uses the fact that when a photoreceptor drum is charged with a stain using a charger and then a certain charged area is exposed to light, the amount of charge in the exposed area decreases. A record of the process of placing a polarized developer on a photoconductor, transferring it onto paper using a transfer device, separating the photoconductor and paper using a separator, and fixing the toner on the paper. This is a way to get sides.

A high voltage is applied to a discharge wire inside the charger used to charge the photoreceptor. This uses corona discharge to strip the photoreceptor. This is to make it happen. Furthermore, corona discharge can also be used for toner transfer, separation of paper and photoreceptor, and neutralization of YC elements.

Generally, corona discharge starts T! The pressure is affected by humidity, and as the absolute humidity increases, the corona discharge starting voltage decreases. Therefore, when a conventional electrophotographic recording apparatus is used in a humid environment, there is a drawback that the discharge may become a spark discharge that could destroy the entire circuit. If the entire path is destroyed, the charger, transfer device 2 separator, static eliminator, etc. will not perform their original roles, and the photoreceptor will also be damaged.

The object of the present invention is to eliminate the above-mentioned drawbacks and provide a system for each discharger (charger, transfer device, 9 separator) even when the depth changes greatly.

It is an object of the present invention to provide a recording device in which a static eliminator) can continue stable corona discharge and perform stable charging, transfer separation, and static neutralization.

The apparatus of the present invention includes a humidity sensor provided near the photoreceptor, and voltage control means for controlling the voltage applied to the corona emitter 11 in response to the output of the humidity sensor.

Next, the present invention will be explained in detail with reference to the drawings.

FIG. 1 is a block diagram showing one embodiment of the present invention.

This embodiment is applied to a charger for an electrophotographic recording device, and includes a discharge electrode wire 1, a shielding frame 2, a control grid electrode 4, a charged weight of 0, a lamp electrode 11, power sources 3 and 5, a resistor 6,
9 and 7 and a humidity sensor 8. The charged body 10, the radiation 10, and the type 1 frame 11 of the electrode wire 1 are photoconductor parts.0 Figure 2 is a graph showing the humidity characteristics of the corona starting voltage. Start 1. Indicates pressure. As shown in the figure, when the absolute humidity becomes high, the corona starting voltage is low and there is a risk of spark discharge.

FIG. 3 is a characteristic diagram of the humidity sensor 8. As the humidity increases, the resistance value of the humidity sensor decreases.The operation of the charger shown in FIG. 1 will be described below.

At the absolute humidity a2 shown in Figure 2, a voltage y higher than the corona starting voltage b2 is applied to the discharge electrode wire 1 by the power source 5.
is applied to As a result, discharge electrode wire 1 and counter electrode 1
Corona discharge occurs between the photoreceptors 1 and 1, and charges are formed on each of the 10 charged members 11L, and the potential of the photoreceptor becomes a certain charging potential X.

Control grid 1! A voltage of several hundred volts from the power source 3 is applied to the pole 4. Is control grid electrode 4Qhi a discharge? 1 □ A voltage of the same polarity as the polar wire is applied. 0 If we consider the case where the absolute humidity near the photoreceptor becomes al as shown in Figure 2 due to environmental changes, the corona starting voltage also increases to bx. However, the resistance of the humidity sensor 8 also increases, and the voltage applied to the discharge electrode wire 1 also increases, so that the corona discharge is maintained.
3 and the corona starting voltage drops to b3, the resistance of the humidity sensor 8 also decreases and the voltage applied to the discharge pole wire 1 also decreases, so that the discharge is prevented from breaking down all the way and becoming a spark discharge. I can do it.

Although the present embodiment describes a charger, the present invention is not limited to this, but a similar discharge electrode wire.

It can be applied to equipment of an electrophotographic recording device, such as a transfer device 9 separator, a static eliminator, etc., equipped with a corona emitter 1b having a shielding frame.

In the present invention, by controlling the 11I pressure applied to the wire of the discharge electrode in accordance with the humidity near the photoreceptor, the corona frost can be released favorably even against changes in humidity.
1. ．． This has the effect of realizing a 1-minute transfer and defrosting process.

[Brief explanation of drawings]

Fig. 1 is a block diagram showing one embodiment of the present invention, Fig. 2 is a graph showing the humidity characteristics of corona initiation 1 (1, pressure), and Fig. 3 is a characteristic diagram of the humidity sensor. 1. Discharge electrode wire , 2 ・Shielding frame, 3.5 W current power source, 4... Control grid electrode, 6, 7.9... Resistor, Agent (patent attorney)
original sound

Claims (1)

[Claims] An electrophotographic recording device characterized by comprising a humidity sensor provided near a photoconductor, and a voltage control means for controlling a voltage applied to a corona discharger in response to the output of the humidity sensor.