JPH01267662A - Process cartridge and image forming device - Google Patents

Abstract

PURPOSE:To simplify the constitution of a transfer material conveying machine without the necessity of a conveying guide by adding a function as the conveying guide to the cover of an image carrier which is to protect the image supporting body. CONSTITUTION:Transfer sheets P in a sheet feeding tray 2 are fed one by one a sheet feeding roller 3, fed to the side of a pair of conveying rollers 5 on the conveying guide 4 as an arrow P1 shows in a figure, and is fed by a proper timing to a transferring part which is between a photosensitive drum 12 and a transfer roller 6 by the conveying roller 5. A drum cover 17 in opening condition is included between the conveying roller 5 and the transferring part, and functions as a sheet conveying guide. Therefore, the transfer sheets which are fed out from the conveying roller 5 are smoothly conveyed to the transferring part along a circular recessing surface 17a which is formed inside the drum cover 17. Thus, the constitution of a mechanism for conveying a transfer material can be simplified.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to a process cartridge configured as a unit including process equipment such as an image carrier, and a laser beam produced by loading the process cartridge into a main body. The present invention relates to an image forming apparatus using electrophotographic technology, such as a printer and a copier Ia.

(Prior art) Image forming apparatuses that adopt the so-called cartridge attachment/detachment method
In this case, a process cartridge 11 as shown in FIG.
The process cartridge 110 is configured as a unit by compactly housing a photosensitive drum 112 as an image carrier and other process equipment (not shown) in one housing 111.

Incidentally, the process cartridge 110 is provided with a drum cover 117 that opens and closes an opening 111a that opens below the photosensitive drum 112 of the housing 111. attached to the end of the Then,
When the process cartridge 110 is removed from the apparatus main body, the surface of the photosensitive drum 112 is protected by being covered by the tram cover 117 which is in the closed state as shown by the solid line in FIG. On the other hand, when the process cartridge 110 is loaded into the main body of the apparatus, the drum cover 117 rotates in the direction of the arrow in the figure around the shaft 116, as shown by the broken line in FIG.
This allows the photosensitive tram 112 to be used for image formation.

(Problems to be Solved by the Invention) However, the conventional process cartridge 110 described above
In this case, the drum cover 117 moves in parallel and has only the function of protecting the photosensitive drum 112, so it is necessary to separately provide a paper conveyance guide, which makes the paper conveyance mechanism inside the apparatus body complicated. There was a problem of becoming

By the way, the conventional process cartridge 1 shown in FIG.
10, the process cartridge 1 of the user
A rib 119 is provided on the drum cover 117 to facilitate handling of the drum cover 10, and a light-shielding mylar 120 is provided at the joint between the drum cover 117 and the housing 112 to prevent exposure to external light from the photosensitive tram 112. Therefore, it was impossible to use the drum cover 117 also as a paper conveyance guide.

The present invention has been made in view of the above problems, and its objectives are: *A process cartridge and image forming system that can simplify the structure of the transfer material transport mechanism by using the carrier cover also as a transport guide. We are here to provide you with the equipment.

(Means for Solving the Problems) In order to achieve the above object, the present invention is configured to be detachable from the mounting body and include at least an image carrier,
In a process cartridge having an image carrier cover that protects an image carrier, one end of the image carrier cover is rotatably pivoted, and when the image carrier cover is in an open state, one surface of the image carrier cover is used as a transfer material. aC as a conveyance guide surface
It is characterized by:

(Example) Embodiments of the present invention will be described below based on the accompanying drawings.

FIG. 1 is a cross-sectional view of the main parts of an image forming apparatus according to the present invention. In FIG. A photosensitive drum 12 serving as an image carrier rotatably driven in the direction of the arrow shown in the figure, and a developing device 13 disposed around the photosensitive drum 12. The charger 14 and the cleaning device 15 are compactly housed and configured as a unit.

By the way, in the process cartridge 1o,
An opening 11a through which a part of the photosensitive drum 12 should face is formed in a part of the housing 11.
a is opened and closed by a drum cover 17 having an arcuate cross section, one end of which is rotatably connected to the housing 11 by a shaft 16.

On the other hand, inside the device main body 1,! 11100 transfer paper P...
A paper feed tray 2 containing a paper feed roller 3, which is rotatably driven in the direction of the arrow shown in the figure. A pair of conveyance rollers 5 and a transfer roller 6, which are rotationally driven in the direction of the illustrated arrow in the conveyance guide 41, are arranged in this order from the right to the upper left diagonally in FIG.

When the process cartridge 10 is removed from the apparatus main body l, the drum cover 17 closes the opening 11a and covers the surface of the photosensitive tram 12, as shown by the broken line in FIG. Protecting.

However, when the process cartridge 1O is loaded into the apparatus main body 1 as shown in FIG. However, as described later, the drum cover 17 functions as a paper conveyance guide. When the drum cover 17 is opened in this way, an opening 11a opens into the main body l, and the transfer roller 6 is brought into pressure contact with the outer periphery of the photosensitive tram 12 facing this opening 11a.

As described above, when an image formation instruction is given after the process cartridge IO has been loaded into the *a main body 1,
The surface of the photosensitive drum 12, which is rotationally driven in the direction of the arrow shown in the figure, is uniformly charged by a charger 14, and then is irradiated with light emitted from an exposure system (not shown), whereby the surface of the photosensitive drum 12 is uniformly charged. An electrostatic WI image is formed. The static "M, WI" images are then visualized by the developer contained in the developing device 13.

On the other hand, at the same time as [ ], the transfer paper P in the paper feed tray 2
are sent out one by one by the paper feed roller 3, and are sent on the conveyance guide 4 toward the conveyance roller pair 5 side as shown by the arrow P1 in the figure, and the conveyance roller 5 transfers them to the photosensitive drum 12 at an appropriate timing. and the transfer roller 6. However, in this embodiment, the drum cover 17 in the open state is interposed between the conveyance roller 5 and the transfer section and functions as a paper conveyance guide. Therefore, the transfer paper P sent out from the conveyance roller 5 is transferred to the tram cover 17.
The recording medium is smoothly conveyed to the transfer section along an arcuate concave surface 17a formed inside the recording medium.

Thus, the transfer paper P that has reached the transfer section receives the transfer of the visible image formed on the photosensitive drum 12 onto its surface by the action of the transfer roller 6, and then.

It is conveyed in the direction of arrow P2 in the figure and reaches a fixing device (not shown), where the transferred image is fixed, and finally it is discharged outside the machine.

As described above, in this embodiment, the drum cover 17
In addition to its original function of protecting the photosensitive drum 12, it also functions as a paper conveyance guide, so there is no need to separately install a paper conveyance guide on the device main body l side, and the structure of the paper conveyance mechanism is simplified accordingly. This makes it possible to reduce costs and reduce costs. Further, since the drum cover 17, which also functions as a paper conveyance guide, is pivotally attached to the housing 11 by the shaft 16, by increasing the positional accuracy of the shaft 16 with respect to the photosensitive drum 12, the transfer paper P can be transferred to the transfer portion. Entry can be made with high precision. Furthermore, in this embodiment, since the transfer paper P is conveyed along the inner concave surface 17a of the drum cover 17, ribs are provided on the outer peripheral surface of the drum cover 17 as in the conventional case, so that the drum cover 17 and the housing are provided with ribs. It is also possible to provide a light-shielding Mylar at the joint portion with 11.

Next, a modified embodiment of the present invention will be described based on FIG. 2. In FIG. 2, the same elements as those shown in FIG. 1 are given the same reference numerals.

In this embodiment, the drum cover 27 opens upward from the closed state shown by the broken line in the figure as shown by the arrow A in the figure with the vehicle 26 as the center and comes to rest at the solid line position L, and the drum cover 27
Reference numeral 7 functions as a paper conveyance guide for guiding the transfer paper P, on which the visible image has been transferred in the transfer section, from the transfer section to the fixing device 18, as shown by an arrow P3. And fuser 1
The transfer paper P guided up to 8 has a visible image fixed thereon, and is then discharged onto a paper discharge tray 20 by a paper discharge roller 19 and stacked there.

Thus, the same effect as described above can be obtained in this embodiment, but in particular in this embodiment, the transfer paper P is deformed into a loop shape along the four sides 27a of the drum cover 27 having an appropriate curvature. However, since it is guided to the fixing device 18, it smoothly enters the fixing device 18, and as a result, problems such as image blur caused by shock at the time of entry are effectively eliminated.

In the above embodiments, an image forming apparatus having a paper transport mechanism in which the transfer paper is fed from the bottom and discharged from the top is referred to. However, in the present invention, on the contrary, the transfer paper is fed from the top. Of course, the scope also includes image forming apparatuses and the like having a paper conveyance mechanism in which the paper is transported and discharged from the bottom.

(Effects of Development II) As is clear from the above explanation, according to the present invention, a function as a conveyance guide is added to the image carrier cover that protects the image carrier. This eliminates the need for a conveyance guide, which has been previously used, and it is possible to achieve the effect that the structure of the transfer material conveyance mechanism can be simplified.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of main parts of an image forming apparatus according to the present invention, and FIG.
The figure is a cross-sectional view of the main parts of an image forming bag according to a modified embodiment of the present invention, and FIG. 3 is a cross-sectional view of a conventional process cartridge. l...Image forming apparatus main body, 10-.Process cartridge, 12...Photosensitive drum (image bearing member), 16°1/26-0. Shaft, 17.27...Drum cover (image carrier cover), 17a, 27a...Concave surface (conveyance guide surface)
, P... Transfer paper (transfer material). Patent applicant Canon Co., Ltd.

Claims (2)

[Claims] (1) A process cartridge that is detachable from the apparatus main body, includes at least an image carrier, and has an image carrier cover that protects the image carrier,
A process cartridge, wherein one end of the image carrier cover is rotatably pivotally mounted, and one surface of the image carrier cover is configured as a transfer material conveyance guide surface when the image carrier cover is in an open state. (2) An image forming apparatus in which the process cartridge is loaded into its main body.