JPS6261950B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an image forming apparatus. An electrophotographic device used as an image forming device has a so-called electrophotographic device that first forms an image of a document as an electrostatic latent image on a photoreceptor as an image carrier, develops this image, and then transfers it to copy paper as recording paper. A known method employs a PPC method or a method in which an electrostatic latent image formed on a photoreceptor is further transferred as an electrostatic latent image onto copy paper, and then this copy paper is developed. In any of these electrophotographic methods, because the object to be copied is paper, paper jams may occur in the copy paper transport path within the apparatus.

Incidentally, in electrophotographic apparatuses, photoreceptors are often formed into a drum shape as copying speeds increase and apparatuses become more compact. Therefore, the above
In an electrophotographic device that uses the PPC method, the original image developed on the photosensitive drum is transferred to the copy paper while the copy paper is pressed against the photosensitive drum.
Copy paper is likely to jam in this transfer area. In an example of an electrophotographic apparatus that employs the other method described above, electrostatic recording paper is used as copy paper, and the recording paper and a screen-shaped photosensitive drum are opposed to each other with a slight distance between them. While applying high voltage, a corona ion stream is projected from the photosensitive drum side to transfer the electrostatic latent image formed on the photosensitive drum onto the recording paper. The recording paper is likely to be attracted to the recording drum side, and there is a possibility that the recording paper may become jammed in this area.

For this reason, conventionally, in order to repair the paper jam in the transfer area, methods such as opening the top of the device or opening the side wall of the device and pulling out the copy paper that is jammed in the transfer area have been used. However, none of these methods can be considered reasonable for the following reasons.

In other words, when opening the top of the device and taking out copy paper stuck in the transfer area, this open area can be relatively wide, but in reality, the transfer roller or copy paper conveyance roller described later is used in this transfer area. , as other structures are attached;
Removal of the copy paper is very difficult and can sometimes damage the photosensitive drum. In addition, when opening the side wall of the device and removing copy paper stuck in the transfer area, pull it out horizontally between the photosensitive drum and other structures, that is, perpendicular to the direction of travel of the copy paper. Therefore, it is difficult to remove the copy paper without damaging the photosensitive drum to some extent.

Furthermore, if the copy paper always has a certain length, such as cut paper, it is possible to pull out the paper by grasping at least one of its ends using either of the above-mentioned removal methods, but if the copy paper is a roll paper If an extremely short piece of paper gets jammed by mistake, it is almost impossible to eliminate this problem.

SUMMARY OF THE INVENTION An object of the present invention is to provide an image forming apparatus that can easily and safely remove the jammed copy paper when it becomes jammed in its conveyance path.

The present invention provides an image forming apparatus in which an image formed on an image carrier is transferred onto recording paper conveyed from a paper feed section in a transfer section, and a fixed image is formed in a fixing section. are both arranged on the side opposite to the image carrier with respect to the transfer section, and the direction in which the recording paper is conveyed in the paper feed section is opposite to the direction in which the recording paper is conveyed in the fixing section after passing through the transfer section. A structure that integrally holds at least the paper feeding section, the transfer section, the fixing section, and the recording paper transportation path is formed in a direction perpendicular to the width direction of the image carrier. The device is characterized in that it is configured to be movable in a substantially horizontal direction.

The present invention will be described in detail below with reference to the drawings.

FIG. 1 is a diagram showing the configuration of an example of an electrophotographic apparatus. In this example, after an electrostatic latent image of an original document formed on a drum-shaped photoreceptor is further transferred as an electrostatic latent image onto copy paper, An electrophotographic apparatus that employs this method of developing copy paper is shown. A document (not shown) placed on a document table 1 is illuminated by an illumination lamp 2, and the reflected light is guided to a photosensitive drum 6 via a reflection mirror 3, a shutter 4, and a projection lens 5. Further, the rotation of the photosensitive drum 6 and the sliding movement of the document table 1 are synchronized, and inside the photosensitive drum 6,
A first corona charger 7 is disposed in front of the light image irradiation section when viewed in the rotating direction, and charges the photosensitive drum 6 uniformly. Therefore, the photosensitive drum 6
An electrostatic latent image corresponding to the original image is formed thereon in the light image irradiation section. This electrostatic latent image is created by modulating the corona ion flow from the second corona charger 8 placed inside the photosensitive drum 6.
The image is transferred via the second corona charger 8 and the photosensitive drum 6 to a copy sheet that is conveyed to an opposing position.

On the other hand, the rolled copy paper 9 is fed by a paper feed roller 10 that rotates in synchronization with the rotation of the photosensitive drum 6.
and cut into a desired length by a cutter 11. The cut copy paper is led to a transfer conveyor belt 13 via a paper guide 12, and is exposed to the photosensitive material by ion projection from the second corona charger 8 at a position facing the second corona charger 8 mentioned above. The electrostatic latent image of the document formed on the sexual drum 6 is transferred. The copy paper onto which the electrostatic latent image has been transferred passes through a developing device 14, a squeeze roller 15, a suction roller 16, a drying roller 17, and a discharge roller 18, and then is delivered to a tray 19 as a clear image.
Note that the reference numeral 20 is an outer box, which effectively holds the above-mentioned components and also effectively blocks external light. Reference numeral 21 denotes a light-shielding partition plate that surrounds the photosensitive drum 6 except for the transfer portion, and introduces only the light reflected from the original by the opening/closing operation of the shutter 4 described above.

In the above-mentioned electrophotographic apparatus, the above-mentioned components arranged in the copy paper transport path from when the rolled copy paper 9 is cut to when it is carried into the developing device 14 are held together by the structure 22. This structure 22 is made movable or removable with respect to the photosensitive drum 6 and the device outer box 20 in the radial direction of the photosensitive drum 6 and approximately horizontally as shown by double arrows. In addition, in this example, the power supply circuit of the device is turned on or off in response to the movement or insertion/removal operation of the structure 22.
An interlock switch 23 that turns OFF is provided.

In the electrophotographic apparatus shown in FIG. 1, when a paper jam occurs near the transfer area and this is detected by some detection means, the structure 22 is moved in the radial direction and horizontal direction of the photosensitive drum 6 as described above. When moved, the space between the photosensitive drum 6 and the conveyance path in the transfer section is opened, and the left side (with respect to the figure) of the developing device 14 and the partition plate 21 is largely opened. On this occasion,
Since the power supply circuit is released by operating the switch 23, the high voltage at the transfer portion is cut off. Therefore, at the transfer portion of the photosensitive drum 6, that is, at the opening of the partition plate 21 facing the second corona charger 8, the copy paper partially wrapped around the drum 6 can be easily and safely removed. Furthermore, paper jams occurring in the copy paper transport path within the structure 22 and paper jams that have partially entered the developing device 14 can be easily removed.

FIG. 2 shows that after an electrostatic latent image of a document is formed on a photosensitive drum 31, a copy paper 32 is pressed against this drum 31, thereby transferring the electrostatic latent image formed on this drum 31 onto the copy paper 32. 3 is a diagram illustrating another example of an electrophotographic apparatus that employs a method in which the copy paper is then developed through a developing device 33. FIG. In the electrophotographic apparatus shown in FIG. 2, paper jams are likely to occur at the portion where the copy paper 32 is pressed against the photosensitive drum 31. 3
8 and 38' are held together by a structure 39 shown by imaginary lines, and this structure 39 is configured to be movable in the radial direction of the photosensitive drum 31 and approximately horizontally, or to be inserted into and removed from the photosensitive drum. . In this way, it is possible to easily eliminate paper jams in the area where the copy paper 32 comes into pressure contact with the photosensitive drum 31, as well as paper jams in the copy paper transport path leading to this area and in the developing device 33. .

FIG. 3 is a diagram showing an example of an electrophotographic apparatus that employs the above-mentioned PPC method as an embodiment of the present invention. Even in this type of apparatus, paper jams occur when the copy paper 42 is placed on the photosensitive drum 41. This tends to occur in areas that are pressed together. For this reason, in FIG. 3, a container 43 for storing sheet copy paper 42 and a paper feed roller 44 as a paper feed section, a transfer roller 45 as a transfer section, a heat fixing device 46 as a fixing section, and a paper feed section. The conveyance path of the copy paper 42 from the transfer section to the fixing section is held together by a structure 47 shown by an imaginary line, and this structure 47 is arranged in a direction perpendicular to the width direction of the photosensitive drum 41 and approximately horizontally. It is configured such that it can be moved or inserted into and removed from the copy paper ejection side of the apparatus outer box 48 in the direction of the copy paper discharge side of the apparatus outer box 48. In this way, the copy paper 42 is placed on the photosensitive drum 41.
It is possible to easily eliminate paper jams in the conveyance path of the copy paper 42 as well as paper jams in the portions where the copy paper 42 is pressed. Note that reference numeral 49 is a developing device for developing the electrostatic latent image of the document formed on the photosensitive drum 41.

Note that the above-mentioned example is not limited, and many changes and modifications are possible. For example, the first
In the electrophotographic apparatus shown in the drawings and FIG. 2, roll-shaped copy paper is used, but the copy paper may also be in the form of a sheet as shown in FIG. 3. Furthermore, even in FIG. 3 showing an embodiment of the present invention, the present invention is not limited to sheet-shaped copy paper, and it goes without saying that roll-shaped copy paper can be used.

As described above, in the present invention, a structure that integrally holds at least a paper feeding section, a transfer section, a fixing section, and a recording paper conveyance path is arranged in a direction perpendicular to the width direction of the image carrier and in a substantially horizontal direction. By moving the structure, the entire transport path of the recording paper from the paper feed section to the transfer section to the fixing section is separated from the image carrier in one direction. No matter where the paper jam occurs, the jammed recording paper is often pulled out along with the structure, making it extremely easy to remove the jammed recording paper without damaging the image carrier. .

[Brief explanation of the drawing]

1, 2, and 3 are diagrams showing the configurations of three examples of electrophotographic apparatuses employing different electrophotographic methods, and FIG. 3 shows an embodiment to which the present invention is applied. . 6, 31, 41...photosensitive drum, 9, 32,
42... Copy paper, 10, 35, 44... Paper feed roller, 11, 36... Cutter, 12... Paper guide, 38, 38', 45... Transfer roller, 20,
40, 48... Outer box, 22, 39, 47... Structure.

Claims (1)

[Claims] 1. In an image forming apparatus that transfers an image formed on an image carrier onto a recording paper conveyed from a paper feed section in a transfer section and forms a fixed image in a fixing section, the paper feed section and the fixing section are both connected. The recording paper is disposed on the side opposite to the image carrier with respect to the transfer section, so that the direction in which the recording paper is conveyed in the paper feeding section is opposite to the direction in which the recording paper is conveyed in the fixing section after passing through the transfer section. , a structure forming a recording paper conveyance path and integrally holding at least the paper feeding section, the transfer section, the fixing section, and the recording paper conveyance path in a direction perpendicular to the width direction of the image carrier and An image forming apparatus characterized in that it is configured to be movable in a substantially horizontal direction.