JPS58132268A - Cleaning device - Google Patents

Abstract

PURPOSE:To prevent the disorder of a picture completely at high humidity by arranging the 1st magnet roller which contacts an image carrier at a cleaning blade upstream side and the 2nd magnet roller for capturing toner falling therefrom at a further upstream side. CONSTITUTION:The cleaning blade 7 scrapes stilling matter on the image carrier by contacting the surface of the rotating image carrier 1, and on an upstream side of the blade, the 1st magnet roller 11 which forms a toner brush 10 for contacting the surface of the image carrier is arranged; and the 2nd magnet roller 8 for capturing toner failing from the roller 11 is arranged at a further upstream side. The blade 12 is arranged facing the magnet roll 11 to form the toner brush 10 of specific thickness on the 1st magnet roller 11. Consequently, the scattering, falling, etc., of toner are prevented and the disorder of a picture on a high-humidity condition is prevented completely.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a cleaning device in an image forming apparatus such as a copying machine. The present invention relates to a cleaning device that is equipped with means for promoting a polishing effect.

Conventionally, as a cleaning device, there is a method in which the edge of a blade such as a cleaning fm is still in contact with the surface of an image carrier to scrape off residual toner and collect it with a collecting means. This is an effective method for removing residual toner, but while cleaning blades are effective for removing residual toner,
Deposits deposited from paper, etc., or foreign matter generated by corona discharge cannot be removed from the surface of the image carrier; rather, they tend to form a strong film on the surface of the image carrier due to the coating effect of the blade. There is. The polishing effect of the toner particles accumulated in the grade area is effective for removing such foreign substances, but the amount of toner in the grade area varies depending on the amount of blank space in the original document, so it is not always necessary to remove foreign substances. However, it is not always the case that an amount of toner sufficient to produce such a polishing effect is deposited on the blade portion, and this is an uncertain factor.

The present invention achieves the abrasive effect of the toner by constantly supplying toner to the blade section regardless of the amount of blank space on the document in order to remove deposits on the surface of the image carrier, and also to prevent toner scattering. To provide a cleaning device that can be easily installed without causing problems such as spillage.

That is, the present invention includes a cleaning blade that comes into contact with the surface of a rotating image carrier to scrape off deposits on the image carrier, and a toner brush that is disposed upstream of the cleaning blade and contacts the surface of the image carrier. The present invention is characterized by comprising a first mudnet roller, a second magnet and a troller, which are disposed further upstream of the first mudnet roller and collect the ζ-sprayed toner from the i-dunnet roller. The present invention provides a cleaning device for cleaning.

Hereinafter, the present invention will be described in detail with reference to the drawings.

FIG. 1 shows a part of a copying machine equipped with a conventionally known cleaning device A. In the figure, 1 indicates an image carrier, on which a static latent image is formed by a known means. The toner image 2 is formed and developed with magnetic toner to obtain a toner image 2. on the other hand,
The transfer material 3 is guided to the front surface of the e-carrier 1 by a guide plate 4, and the toner image 2 is formed on the skeleton transfer material 3 by the action of a charge having a polarity opposite to that of the toner given by a transfer corona discharger 5 from the back surface. transcribed. Thereafter, the transfer material 3 is separated from the surface of the image carrier 1 by separation rollers 6 and sent to a fixing section (not shown).

The cleaning device A removes toner remaining on the Kfll carrier 1 after transfer, and includes a cleaning blade 7 and a collecting magnet that are in contact with each other in a direction opposite to the rotational direction of the image carrier 1. , troller 8 and conveyance screen, -9
A cleaning blade r7 scrapes the remaining toner after transfer from the surface of the image carrier 1, and the magnetic toner removed by the cleaning blade is collected and collected by a collection magnet roller 8 whose poles are appropriately arranged. Then, it is carried out of the cleaning device by the conveyor screw .-9. In this way, the image carrier 1 can be used repeatedly.

Although the residual toner on the image carrier 1 is removed by the cleaning device described above, foreign matter adheres to the surface of the image carrier 1 due to the repetition of the above-mentioned gross removal.

In particular, the adhesion of substances such as rosin deposited from the transfer paper is noticeable, and these adhesion substances cannot be removed with a cleaning blade.Therefore, in the past, abrasive powder such as cerium oxide was added externally to the toner in advance. Then, the abrasive powder supplied to the surface of the image carrier along with the toner is used by the cleaning blade to remove deposits on the drum surface, and these deposits absorb moisture under high humidity, reducing surface resistance. A method has been adopted to prevent the disturbance of the image (latent gI) caused by this. However, if the original has some margins and toner (abrasive) is not supplied to the original, in other words, if a nearly blank original is copied continuously, the image bearing There is very little developed toner on the body, and therefore, the supply of abrasive powder such as cerium oxide in the toner is insufficient, and it is not possible to obtain a complete cleaning effect with this method.

The present invention adds means for separately supplying toner and abrasive powder to the cleaning blade section in addition to the toner supplied from the developing device, thereby eliminating the drawbacks of the conventional apparatus.

FIG. 2 shows an embodiment of the cleaning device of the present invention. The cleaning device shown in FIG. 7, a first magnet and a troller 11 forming a toner brush 10 disposed upstream of the cleaning blade 7 and in contact with the surface of the cough image carrier 10.
The basic configuration includes a second magnet and troller 8, which is disposed further upstream of the first magnet and troller and collects stray toner from the magnet and troller. An fv-dot 12 is disposed facing the magnet and troll 11, and is configured to form a toner brush 1o of a constant thickness on the first ladder net roller 11.

During operation, the magnetic toner removed from the surface of the image carrier by the grade 7 is captured by the first magnet, the troller 11, and as described above, the toner brush 1o of a constant thickness is transferred by the grade 12 to the magnet roller 11. formed on top. At this time, the toner brush thickness is the same as that of the image carrier 1, the magnet,
To make the gear lag with the troller 11 larger, use the f-rade 12! In other words, the gap between the toner brush 10 and the troller 11 is adjusted, and the toner brush 10 moves in the opposite direction to the rotational direction of the image carrier without contacting the surface of the image carrier. is 0.1~0.3 vpjm
However, the problem with this method is that the abrasive action of toner supply to the surface of the image carrier and the rubbing of the toner brush can be expected to be very effective in removing deposits from the surface of the image carrier. The problem is toner flaking due to rubbing and contact, and although it is desirable to increase the amount of contact in order to remove deposits, the toner and flaking increases dramatically. Conversely, if the amount of contact is reduced to prevent toner from spilling, the effect of removing deposits will also be reduced. As long as the pick and toner brush are in contact with each other, the toner will adhere due to the charge applied to the image carrier during transfer, and the cleaning plate 97 will have a polishing effect, but it will not be sufficient to completely remove the deposits. In order to
The rubbing force of the toner brush is required.

Therefore, the thickness of the toner brush is set so that the toner brush makes enough contact to have a sliding force, and in order to prevent toner from clogging, a toner collecting magnet and troller 8 are installed further upstream of the magnet roller 11. This is to collect the scattered toner from the roller 11 and prevent the toner from falling outside the cleaning device. The collection roller 8 also has a casing portion 13 which acts as a scree nose and forms a toner brush, but the thickness of this toner brush must be such that it does not come into contact with the surface of the image carrier and has a certain gear. In the experiment, 0.
It is preferable to have a gap of 1 to 0.3 ny'm.

In the above device, the roller 1
It is desirable that 1 be rotated in the opposite direction to the 1# carrier.
Depending on the amount of deposits and the configuration, rotation in the forward direction may be sufficient to achieve a leaning effect.

As mentioned above, the present invention can completely remove foreign matter adhering to the surface of the image carrier without causing any adverse effects such as toner and flaking, and therefore completely eliminates image distortion under high humidity. It can be prevented.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing a part of a copying machine equipped with a conventional cleaning device, and a second enlarged side view showing the cleaning device of the present invention. 1... Image carrier 2 River toner image 3... Transfer material 4... Guide plate 5... Transfer core discharge device
6... Separation core a7... Cleaning blade 8... Collection magnet, draw 2

Claims (1)

[Scope of Claims] A cleaning blade that contacts the surface of a rotating image carrier to scrape off deposits on the image carrier, and a toner brush that is disposed upstream of the cleaning blade and contacts the surface of the image carrier. A first magnet forming a troller, and a second magnet disposed further upstream of the first magnet roller to collect stray toner from the magnet roller. A cleaning device characterized by a roller consisting of a roller.