JPS62239184A - Electrophotographic device - Google Patents

Abstract

PURPOSE:To reduce cost and relieve restriction upon layout by constituting the toner attracting fur of a means, which destaticizes and cleans a photosensitive body, with conductive fibers having 10<8>-10<11>OMEGA/cm resistance value. CONSTITUTION:A brush roll 24 attracts the toner from the surface of a photosensitive body 10 by the electrostatic attraction of a power source E1 and the frictional action of a fur 25, and a recovery roll 26 recovers the toner on the fur 25, and a blade 26 scrapes it. The surface potential of the photosensitive body is about zero volt because the fur 25 consists of conductive fibers having 10<8>-10<11>OMEGA/cm resistance value,and the destaticizing effect is not sufficient in case the resistance value exceeds this range, and the surface is damaged by spark if there are pinholes on the surface of the photosensitive body in case the resistance value is smaller than the lower limit of this range. Thus, the structure is simplified to reduce the cost, and restrictions on layout are relaxed.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention relates to electrophotographic devices such as printers, copiers, and facsimiles, and in particular, the present invention relates to electrophotographic devices such as printers, copiers, and facsimile machines. After transcribing the
The present invention relates to an electrophotographic apparatus that eliminates static electricity from a photoreceptor drum and cleans toner remaining on the surface of the photoreceptor drum.

[Prior Art] An electrophotographic apparatus using the above method requires processes of charging, exposure, development, transfer, cleaning, and static elimination, and in a conventional electrophotographic apparatus, means for each process are separate. It was done by a device. especially,
means for removing electric charges on the surface of the charged photoreceptor drum;
There has been no device in which the means for cleaning the toner remaining on the surface of the photoreceptor drum after transfer is the same device.

[Problems to be Solved by the Invention] As described above, in conventional electrophotographic devices, the static eliminating means and the cleaning means are manufactured as separate devices, resulting in high manufacturing costs. Therefore, there were restrictions on the layout of the electrophotographic device.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems and to provide an electrophotographic apparatus that can reduce manufacturing costs and layout constraints.

[Means for Solving the Problems] In the electrophotographic apparatus of the present invention, means for eliminating static electricity from a photoreceptor drum and means for cleaning residual toner are comprised of a single device, and this apparatus eliminates static electricity caused by a bias voltage. A brush roller that attracts electricity from the surface of the photoreceptor drum,
Similarly, it consists of a collection roller that attracts the brush roller by electrostatic attraction due to a bias voltage, and a blade that shakes it off the surface of the collection roller, and the hairs of the brush roller have an average resistance value of 108 to 1°11Ω/CtX. It is made of conductive fibers.

[Function] In the electrophotographic apparatus of the present invention, a single device having both a static elimination function and a cleaning function performs static elimination and cleaning as described below. That is, the bristles of the brush roller are formed of conductive fibers having an average resistance value of 10 8 to 10 11 Ω/ax, and since a bias voltage is applied, the surface of the photoreceptor drum is neutralized. Further, since a bias voltage is applied to the bristles of the brush roller, the toner remaining on the surface of the photoreceptor drum is attracted to the brush roller by electrostatic attraction.

Since a bias voltage is applied to the collection roller, the toner attracted to the brush roller is attracted to the collection roller by electrostatic attraction, and the toner attracted to the collection roller is shaken off by the blade.

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

Reference numeral (10) denotes a photosensitive drum disposed inside the electrophotographic apparatus, and is mounted so as to be rotatable in the direction of arrow (1) via a support shaft (12).

A photoconductor made of an organic semiconductor is adhered to the surface of the photosensitive drum (10) to form a photosensitive layer.

(14) is a contact charger made of a brush arranged inside the electrophotographic apparatus at a position suitable for charging the surface of the photoreceptor drum (10).

The contact charger (14) is connected to the support shaft (
A large number of conductive fibers arranged in parallel in the direction 12) have a U-shaped cross section and are held between support members made of a band-shaped conductive material. The conductive fibers are attached so that the unpinned portions can rub the surface of the photoreceptor drum (10). Further, since the conductive TL fibers are connected to a negative bias voltage power source via the support member, the surface of the photoreceptor drum (10) is connected to the contact charger (1).
4) gives a uniform negative charge.

As the photoreceptor drum (10) rotates, the negatively charged surface of the photoreceptor drum (10) faces a writing device (not shown). Then, the write-in device irradiates the surface of the photoreceptor drum (10) with a semiconductor laser beam (16) according to the recorded content. The portion of the surface of the photoreceptor drum (10) that is irradiated with light becomes electrically conductive, and the surface potential of that portion becomes 0 volts.

(18) is a developing device that develops the surface of the photoreceptor drum (10) using a one-component toner, and a negative voltage is applied to a portion of the surface of the photoreceptor drum (10) where the surface potential is 0 volts. The charged toner is applied via a brush roller.

(18) is a transfer device that transfers the toner attached to the surface of the photoreceptor drum (10) onto the recording paper, and the toner is transferred from the surface of the photoreceptor drum (10) to the recording paper by charging the recording paper. It gets attracted towards you. It is preferable that all the toner on the surface of the photoreceptor drum (10) be transferred to the recording paper by this transfer device, but in reality, 20 to 3
0% of the toner remains untransferred on the surface of the photosensitive drum (10).

(20) is a device that has both a static eliminating function and a cleaning function that eliminates static electricity from the surface of the photosensitive drum (10) and removes toner remaining on the surface of the photosensitive drum (10). (22) is a housing of the device (20) having approximately the same length as the photoreceptor drum (10), and is installed inside the electrophotographic apparatus so that its opening faces the photoreceptor drum (10). installed. (24) is a brush roller disposed inside the housing (22) near the opening, and this brush roller (24) is formed to have approximately the same length as the photoreceptor drum (10). Ori,
It has a support shaft passing through the center, a metal drum supported by the support shaft, and a large number of bristles (25) made of conductive fibers planted on the surface of the drum. The brush roller (24) is pivotally attached to both ends of the housing (22) so that the tips of the bristles (25) can rotate in the direction of the arrow (2) while contacting the surface of the photoreceptor drum (10). At the same time, it is connected via a support shaft to a bias voltage power supply (El) that provides a positive potential. Brush roller (
24) from the surface of the photoreceptor drum (10) due to the electrostatic attraction generated by the bias voltage power source (El) and the laminar action of the bristles (25) of the brush roller (24).
adsorbs ner. (26) is a collection row that collects the toner adsorbed by the bristles (25) of the brush roller (24), and is located inside the housing (22) with respect to the photosensitive drum (24). 10) is placed on the opposite side. The collection roller (26) has a spindle passing through the center and a metal drum (21) supported by the spindle, and the surface of this drum (27) is similar to that of the brush roller (24). While touching the hair (25) of the arrow (
It is pivotally attached to both ends of the housing (22) so as to be rotatable in the direction 3). In addition, this collection roller (26)
is connected to a bias voltage power source (E2) having a positive voltage larger than the bias voltage power source (El) via a spindle, and the brush roller is (24) hair (2
5) Adsorbs toner from. (28) is the collection roller (
26) is a blade that shakes down the toner collected in the housing (26), and is disposed in the inner part of the housing (22). The blade (28) is a band-shaped plate, and is fixed to the side wall of the housing (22) so that one longitudinal corner thereof comes into contact with the drum (27) of the collection roller (26). Also,
Reference numeral (29) is a hole for sucking out the agitated toner to the outside, and 1 is provided near the bottom of the inner portion of the housing (22).

In this example, the surface of the photoreceptor drum (10) is given a surface potential of -600 volts by the contact charger (14), and the exposed areas are 0 volts, but the other areas are constant. Same as above, still 600 volts! (20
) can be rotated to a position facing the Then, a potential of +200 volts is applied to the brush roller (24),
The recovery roller (26) is given a potential of +400 volts, and the toner adheres to the O-volt location of the photoreceptor drum (10), so the toner is transferred to the photoreceptor drum (10).
) from the surface of the brush roller (24) to the brush roller (24).
24) to the collection roller (26). In addition,
These potentials are not limited to the potentials in the above embodiments, but may be any potential suitable for adsorbing the toner from the photoreceptor drum (10) to the collection roller (26) via the brush roller (24). Good.

As the conductive fibers forming the bristles (25) of the brush roller (24), those having an average resistance value of 10 to 1011 Ω/α are used. When a conductive fiber having a resistance value within this range is used and a positive potential is applied to the conductive fiber through the spindle, the surface potential of the photoreceptor drum (10) becomes almost O volts, and the static electricity is removed. be done.

In addition, in conventional cleaning devices, conductive fibers with a resistance value of about 108 to 1015 Ω/cm have been used;
If it is larger than , the conductivity will be poor and the static elimination effect will not be sufficient. Also, if the resistance value is smaller than 108 Q/CIR, the conductivity will be better, but on the other hand, the photoreceptor drum (10
) If there is a pinhole on the surface, it will cause sparks and damage the surface. Therefore, the average resistance value of the conductive fiber is 1
A value of 0 to 1011 Ω/aX is preferable.

[Effects of the Invention] According to the electrophotographic apparatus of the present invention, static elimination and cleaning can be performed with a single device, so there is no need to separately manufacture a static elimination device and a cleaning device and incorporate them independently. Therefore, the electrophotographic apparatus of the present invention makes it possible to lower manufacturing costs and reduce layout constraints.

[Brief explanation of drawings]

The drawing is a schematic diagram showing a cross section of an electrophotographic apparatus according to the present invention. Explanation of symbols 10... Photosensitive drum 14... Contact charger 16.
...Semiconductor laser beam 18...Developing device 20...
A device that has both FF removal and cleaning functions

Claims (1)

[Claims] 1. An electrophotographic device that attaches toner to exposed areas of a charged photoreceptor drum, transfers the toner, then neutralizes the photoreceptor drum and cleans toner remaining on the surface of the photoreceptor drum. In this method, the means for neutralizing the photoreceptor drum and the means for cleaning the residual toner are comprised of a single device, and this device consists of a brush roller that attracts the surface of the photoreceptor drum by electrostatic attraction caused by a bias voltage, and a similar device. It consists of a collection roller that attracts the brush roller by electrostatic attraction due to a bias voltage, and a blade that shakes it off the surface of the collection roller, and the brush roller hair has an average resistance value of 10^8 to 10^1^.
An electrophotographic device characterized in that it is formed of conductive fibers having a resistance of 1 Ω/cm.