JPH0473775A - Electrophotographic device - Google Patents

Abstract

PURPOSE:To easily remove a recording sheet when paper jamming occurs by separating a cleaning blade from a photosensitive drum when the paper jamming occurs by the failure of the peeling of the recording sheet after a transfer process. CONSTITUTION:When recording is started, a main charger 2 uniformly electrifies the photosensitive drum 1, an exposure is selectively carried out according to recording data by an LED head 3, and development is carried out by a developing unit 5 to form a toner image on the drum 1. On the other hand, the recording sheet 11 fed from a paper feeding cassette 10 is carried up to a transfer unit 6, and the toner image produced by the developing process of a developing unit 5 is transferred to the recording sheet 11 on the transfer unit 6. The recording sheet 11 is peeled from the drum 1 by a peeling unit 7, fixed by a fixing unit 15, and then, ejected on a stocker 18 via a feeding roller 17. When a sensor 16 is not turned on, the recording sheet 11 is still stuck to the photosensitive drum 1 by the failure of the peeling of the recording sheet 1. At this time, the cleaning blade 8a is released, and then, the display of the paper jamming is carried out.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to electrophotographic devices such as LED plotters, laser printers, and liquid crystal printers, and particularly relates to a cleaning function for removing residual toner adhering to a photosensitive drum after a transfer process. The present invention relates to an electrophotographic apparatus including a blade release means.

[Prior Art] In electrophotographic devices such as LED blocks and laser printers, a photosensitive drum is uniformly charged, an electrostatic latent image is formed by a photosensitive process, and this electrostatic latent image is further developed to produce a resultant image. Recording is performed by transferring and fixing the toner image onto recording paper.

Further, residual toner adhering to the photosensitive drum after the transfer process is removed from the photosensitive drum by a cleaning device equipped with a cleaning blade.

Incidentally, the cleaning blade described above has the function of brushing off residual toner by coming into contact with the photosensitive drum, but if it is left in contact with the photosensitive drum for a long time, toner may be removed at the point of contact with the photosensitive drum. may fuse together. For this reason, generally, when the power is turned off, it is separated from the photosensitive drum, and when the power is turned on, it is pressed against the photosensitive drum.

[Problems to be Solved by the Invention] By the way, in the peeling process after the transfer process, if the recording paper that is in close contact with the photosensitive drum is not peeled off correctly,
The recording paper may slip into the gap between the cleaning blade and the photosensitive drum while remaining in close contact with the photosensitive drum. In this case, it takes a lot of effort to remove the recording paper, and if you try to remove it forcibly, you will damage the cleaning blade and the photosensitive drum.

The present invention has been made in view of such problems, and includes:
To provide an electrophotographic device that can easily remove recording paper and prevent damage to a cleaning blade and a photosensitive drum when a paper jam occurs in a cleaning blade part.

[Means for Solving the Problems] The electrophotographic apparatus according to the present invention includes a photosensitive drum, a cleaning blade that contacts the photosensitive drum and removes residual toner adhering to the photosensitive drum after the transfer process, and a cleaning blade that contacts the photosensitive drum and removes residual toner adhering to the photosensitive drum after the transfer process. paper jam detection means for detecting a paper jam caused by the recording paper not being peeled off from the photosensitive drum in the recording paper peeling process; A cleaning blade releasing means for separating the cleaning blade from the photosensitive drum is characterized.

[Function] According to the present invention, when a paper jam caused by the recording paper not being peeled off from the photosensitive drum in the recording paper peeling process after the transfer process is detected, the cleaning φ blade is separated from the photosensitive drum. Therefore, when a paper jam occurs, the recording paper can be easily removed, and damage to the cleaning blade and the photosensitive drum can be prevented.

[Embodiments] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

FIG. 1 is a schematic diagram showing a schematic configuration of an LED plotter according to an embodiment of the present invention.

That is, a photosensitive drum 1 that rotates in the direction of the arrow in the figure during recording is provided inside the plotter main body. The following elements necessary for the electrophotographic process are arranged around the photosensitive drum 1.

First, a main charger 2 that uniformly charges the photosensitive drum 1 to, for example, 800 to 1000 V is arranged at the most upstream side in the rotational direction of the photosensitive drum 1 . At a downstream position of the main charger 2, there is an LED head 3 consisting of a light emitting diode (LED) array that selectively exposes the photosensitive drum 1 charged by the main charger 2 to light according to recorded data to form an electrostatic latent image. , and a SELFOC lens 4 that images the light from the LED head 3 onto the photosensitive drum 1. At the downstream position of the LED head 3,
A developing device 5 is arranged to supply toner to the photosensitive drum 1 and visualize the electrostatic latent image as a toner image. A transfer device 6 is disposed downstream of the developer 7 and supplies a charge for transferring the toner image formed by the developer 5 onto recording paper. A peeling device 7 is arranged downstream of the transfer device 6 to supply an electric charge to peel the recording paper from the photosensitive drum 1.

A cleaning device 8 is disposed further downstream of the stripper 7 to remove toner attached to the photosensitive drum 1 and clean the surface of the photosensitive drum 1. This cleaner 8 is provided with a cleaning blade 8a. The tip of the cleaning Φ blade 8a contacts the photosensitive drum 1 at the same time when the power is turned on, and separates from the photosensitive drum 1 when the power is turned off and when a paper jam occurs, which will be described later.

Further, at a downstream position of the cleaning device 8, that is, at a position immediately upstream of the main charger 2, a static elimination lamp 9 for removing residual charges on the photosensitive drum 1 is arranged.

Further, a paper feed cassette 10 for holding recording paper 11 is removably provided in the plotter main body. The recording paper 11 held in the paper feed cassette 10 is transferred to the paper feed roller 1
2, the paper is supplied to the paper conveyance path. The recording paper 11 supplied to the paper conveyance path is supplied to the above-described transfer device 6 and peeling device 7 via a sensor 13 and a feed roller 14. Further, a fixing device 15 is arranged downstream of the peeling device 7 in the paper conveyance path. A feed roller 17 is arranged downstream of the fixing device 15, and a stacker 18 for holding recorded recording paper is arranged further downstream.

Next, the operation of the LED plotter according to this embodiment configured as described above will be explained.

When recording is started, the main charger 2 uniformly charges the photosensitive drum 1 to, for example, 5 oov. The charged photosensitive drum 1 is selectively exposed to light by the LED head 3 according to recording data, and is further developed by the developing device 5.

As a result, a toner image is formed on the photosensitive drum 1.

On the other hand, the recording paper 11 supplied from the paper feed cassette 10 is conveyed to the transfer device 6 , and the toner image generated by the developing process of the developing device 5 is transferred onto the recording paper 11 in the transfer device 6 . This recording paper 11 is peeled off from the photosensitive drum 1 by a peeler 7 and fixed by a fixing device 15. Then, it is discharged to the stocker 18 via the feed roller 17.

FIG. 2 is a flowchart showing the procedure for detecting a single paper jam in the series of electrophotographic processes described above.

That is, if the sensor 13 does not turn on after recording has started (S,), a paper out message is displayed (S2).

When the sensor 13 is turned on, the recording paper 11 is moved by a distance corresponding to the distance from the sensor 13 to the sensor 16 arranged downstream of the fixing device 15 (S3), and the sensor 16 is turned on. Check whether it has changed (S4
).

If the sensor 16 is turned on, the recording paper 1
1 means that it was transported normally. The state at this time is shown in FIG. 3(a).

On the other hand, if the sensor 16 does not turn on, as shown in FIG.
As shown in b), the recording paper 11 remains in close contact with the photosensitive drum 1 due to poor peeling of the recording paper 11.

If you leave this as it is, cleaning blade 8
The recording paper 11 gets stuck between a and the photosensitive drum 1, resulting in a paper jam.

Therefore, in this case, the cleaning blade 8
After setting a to the released state as shown in the figure (S5), a paper jam is displayed (S6). Through the above processing, the recording paper 11 can be easily removed when a paper jam occurs, and the photosensitive drum 1 and cleaning - Damage to the blade 8a can also be prevented.

In the above embodiment, the cleaning blade 8a is immediately released when a paper jam occurs. However, for example, the cleaning blade 8a may be released only when the main body cover is opened after a paper jam occurs. good.

[Effects of the Invention] As described above, according to the present invention, when a paper jam occurs due to poor peeling of the recording paper after the transfer process,
Since the cleaning blade is separated from the photosensitive drum, the recording paper can be easily removed when a paper jam occurs, and damage to the cleaning Φ blade and the photosensitive drum can be prevented.

[Brief explanation of the drawing]

Fig. 1 is a schematic diagram of an LED plotter according to an embodiment of the present invention, Fig. 2 is a flowchart showing the paper jam detection procedure in the plotter, and Fig. 3 is a cleaning blade in the plotter during normal operation and when a paper jam occurs. It is a schematic diagram showing the situation in the vicinity. 1; Photosensitive drum, 2; Main charger, 3; LED head, 4; SELFOC lens, 5; Developing device, 6; Transfer device, 7; Peeling device, 8; Cleaning device, 8a: Cleaning blade, 9; Static eliminator Lamp, 10; Paper cassette, 11;
Recording paper, 12; Paper feed roller, 13.16; Sensor, 14
．． 17; Feed roller, 15; Fixing device, 18; Stacker (not shown)

Claims (2)

[Claims] (1) A photosensitive drum, a cleaning blade that comes into contact with the photosensitive drum and removes residual toner attached to the photosensitive drum after the transfer process, and a cleaning blade that removes the recording paper from the photosensitive drum in the process of peeling off the recording paper after the transfer process. A paper jam detecting means for detecting a paper jam due to not being peeled off, and a cleaning blade releasing means for separating the cleaning blade from the photosensitive drum when the paper jam is detected by the paper jam detecting means. An electrophotographic device featuring: (2) The cleaning blade releasing means separates the cleaning blade from the photosensitive drum when the paper jam is detected and a cover of the apparatus main body is opened. Item 1. The electrophotographic device according to item 1.