JPS6263945A - Process cartridge and image forming device using this cartridge - Google Patents

Abstract

PURPOSE:To prevent the degradation or the damage of an image carrier by protecting the image carrier with a shutter. CONSTITUTION:A pair of frames 15 of a cartridge K are provided with an aperture part 30 for image exposure and an aperture part 31 for transfer which is used to transfer the image on a drum 3 onto a sheet P. An exposure shutter 32 and a transfer shutter 33 are provided for aperture parts 30 and 31 respectively so that they can be moved between aperture part covering close positions and aperture part opening positions, namely, they can be opened and closed. The exposure shutter 32 and the transfer shutter 33 protect a photosensitive layer 3a from degradation due to light, damage, or the like.

Description

DETAILED DESCRIPTION OF THE INVENTION [Scope of industrial application] The present invention provides a process cartridge that has an image carrier and a process means that acts on the image force carrier and is removably attached to a predetermined position inside an apparatus main body. The present invention also relates to an image forming apparatus using the process cartridge. The image forming apparatus of the present invention is for recording an image on a recording material, and includes, for example, an electrophotographic copying machine, a micro device, a laser beam printer, and the like.

[Prior art and problems to be solved by the invention] Hereinafter, an explanation will be given using an electrophotographic copying machine as an example.

Conventionally, in an electrophotographic copying machine, there have been various processes such as replacing the photosensitive drum as an image 1 carrier, replenishing toner, disposing of waste toner,
In addition to cleaning the charging wires, it was also necessary to regularly replace and adjust various consumable parts, which was carried out by specialized service personnel. Therefore, a service person had to come each time, which was extremely troublesome.

Therefore, in recent years, as described in Japanese Unexamined Patent Publication No. 51-2433, process means such as a photosensitive drum J1, a developer, a cleaner, a charger, etc. are integrated into a process cartridge, and this process cartridge is replaced. Therefore, it has been considered to replace each means integrally and at the same time to reduce maintenance work. By having the configuration as described above, the user can easily replace each process-related means that requires regular maintenance, and can even replace the process cartridge with a process cartridge that stores toner of a different color. It has advantages such as being able to form color images.

However, the process cartridge has an opening for image exposure and transfer to copy paper, and if the photosensitive drum is exposed to light for a long time, there is a possibility that the photosensitive drum will deteriorate.

Various problems can be considered, such as dirt entering from the open part, touching the photosensitive drum during handling and soiling it, and storing it in a high humidity environment before use, making it moist. These scratches and stains on the photosensitive drum or deterioration of the photosensitive layer adversely affect images.

Therefore, in order to solve these problems, JP-A-57-2
Publication No. 00052 or JP-A-57-211481
As described in the publication, a structure is being considered in which a mechanical shutter member is provided at the opening of the transfer portion of the process cartridge, and this shutter is automatically opened when the cartridge is installed in the machine. .

The present application further improves these conventional techniques. [Object of the Invention] The present invention further improves the prior art, and provides a process cartridge in which the operability of the protective cover covering the opening [1] of the process cartridge is further improved. The present invention also aims to provide an image forming apparatus using the process cartridge.

〔Example〕

In addition, in the examples described below, the process cartridge is
An electrophotographic copying machine that houses an image carrier such as an electrophotographic photoreceptor and at least one other processing means in a frame that can be attached to and removed from a predetermined position within the main body of an electrophotographic copying machine. The process means includes a charger that acts on an image bearing member such as a photoreceptor, a developing device for electrostatic latent images, a cleaning device that removes toner remaining on the photoreceptor, etc. to carry out the image forming process. It refers to a means for applying a predetermined action to an image bearing member, and the main body of an electrophotographic copying machine is a means for accommodating and supporting a process cartridge, a transfer paper conveying means, and a means for transferring a toner image transferred from a photoreceptor. It has a built-in fixing means for fixing it to paper, and is surrounded by an exterior plate.

FIG. 1 is a longitudinal sectional view of an electrophotographic copying machine loaded with a process cartridge C to which an embodiment of the present invention is applied.

In the figure, ■ is a document mounting table made of a transparent member such as glass, which reciprocates along the rail RJ- in the direction of arrow a. Reference numeral 2 designates a short-focus, small-diameter imaging element array, in which an original image of an original O placed on an original placing table l is irradiated by an illumination lamp, and the reflected light image is transmitted by this array 2 to a photosensitive driver i,
31- is slit exposed. Note that this photosensitive drum 3 rotates in the direction indicated by the arrow around @t+3b. A charger 4 uniformly charges the photosensitive drum 3-1- coated with, for example, a zinc oxide photosensitive layer or an organic semiconductor photosensitive layer 3a. Note that 4a is a corona wire. The drum 3, which is uniformly charged by the charger 4, is exposed to the element array 2.
An electrostatic latent image is formed by imagewise exposure. This electrostatic latent image is then visualized by a developer 5 consisting of a doctor blade 5c and a magnet 5d, which does not form a uniform thin film of the sleeve 5a, toner reservoir 5b, and toner T. −・
On the other hand, the sheet P stored in the cassette S is fed into the drum 31 by the registration roller 7, which rotates in synchronization with the feed roller 6 and the image on the photosensitive drum 3. Then, by the transfer discharger 8,
The toner image on the photosensitive drum 3]- is transferred onto the sheet P)-. Thereafter, the j) P separated from the drum 3 by a separating means 13 (for example, a separating belt B or a separating corona discharger shown in the figure) is guided to a fixing device 10 by a guide 9 and a pinch roller 9a. After the toner image on the sheet LP is fixed here, the discharge roller 11
is discharged onto the tray 12. Note that after the toner image is transferred, residual toner on the drum 3 is removed by a cleaner 14. The cleaner 14 includes a blade 14a, a toner reservoir 14b for storing waste toner T', and a scoop sheet 14c. Also, 13a is a separation roller, F is
The heat ray absorption filter 29 is an ozone filter.

16 is a slit opening for guiding the original image to the surface of the drum 3.

In this embodiment, as shown in FIG. 2, a photosensitive drum 3 and a charger 4. The developing device 5 and the cleaner 13 are integrally provided surrounded by a frame 15 serving as a light shielding wall, and constitute a process cartridge K.

As will be described later, this process cartridge is provided so that when the main body C is split open downward, it can be inserted into and removed from a predetermined loading position of the main body C in the direction of the rotational axis of the drum 3. When attaching and detaching the process cartridge to and from C, the sliding portions 15a1115b of the frame 15 of the process cartridge are engaged with the main body side guides 15a and 15b and guided. Note that this frame 15 is made of black rigid plastic,
The material is not limited to this, and may be made of metal or wood.

The frame pair 15 of this cartridge is provided with an opening 30 for image exposure and a transfer opening 31 for transferring the image of the drum 3 onto the sheet P. Further, an exposure shutter 32 is disposed in the opening 30, and a transfer shutter 33 is disposed in the opening 31 so as to be movable between a closed position covering the opening and a position opening the opening. It is set up. In the embodiment described below, the shutter 33 of the opening 30 of the image exposure section is opened and closed in conjunction with the opening and closing of the shutter 33 of the opening 31 of the transfer section.
2 opens and closes.

The exposure shutter 32 and the transfer shutter 33 protect the photosensitive layer 3a from deterioration or damage caused by light.

As shown in FIG. 3, this copying machine C is divided into an upper casing 17 and a lower casing 18, which are connected by a support shaft 19 so as to be separable. It is configured to rotate upward. This upper housing 1
7 includes an illumination optical system 2-L and a photosensitive drum No. 3 developing device 5.
- A cartridge K that integrally has process means such as a cleaner 13 is arranged. In addition, the lower housing 18 includes a cassette Sφ feeding roller 6φ transfer discharger 8 and a separating means 13.
A φ guide 9, a fixing device 10, etc. are arranged along the sheet conveyance path. Then, by rotating the upper housing 17 upward, the sheet conveyance path is opened. Note that 35 is a protrusion that is fixed on the front side of the device main body C, and when closing the lower main body 17, it engages with a lever 26, which will be described later, and rotates the lever 26 counterclockwise against the spring force. By moving the shutter 33 and the shutter 32 automatically.

Next, the interlocking opening/closing mechanism of the shutters 32 and 33 will be explained using FIGS. 4 to 8.

FIG. 4 is a partial view of the central part of the process cartridge K when viewed from the front, showing how the exposure shutter 22 and transfer shutter 33 are connected, and FIG. A diagram showing the longitudinal direction of the shutter 32, FIG. 6 is a perspective view showing the shutter 33 that closes the transfer opening 31, FIG. 7 is a diagram showing the exposure shutter 32 in a closed state, and FIG. 8 is a diagram showing the exposure shutter 32. 32 is a diagram showing a state in which 32 is open.

In the figure, an arm 22 is rotatably provided on the same axis 3b as the photosensitive drum 3, and this arm z2 is rotated clockwise (in the direction of closing the shutter 33) by a torsion coil spring 23.
is energized by. One end 22a thereof is swingably engaged with an end 21a of the transfer shutter 33.

Further, the other end 21b of the transfer shutter 33 is connected to the swing arm 24.
It is pivotally engaged with the end portion 24b of. Furthermore, the other end 24a of this swing arm 24 is fitted into a hole 15b provided in a frame side plate 15a of the process cartridge. A boss portion 25 is provided on the side plate 15a coaxially with the hole 15b. Also, 26 is a lever.

It is rotatable around the post 25, and is connected to the swing arm 24 through a fitting portion 26b provided on the back side.

Further, at one end 26a, a pin 26b provided on the lever 26 is connected to an elongated frontage portion 2 provided at the tip of the lever 27.
It is slidably engaged with 7a. Furthermore, this lever 27
The other end 27b has a pin 32 provided on the exposure shutter.
a is engaged. Note that a spring 28 is attached to this pin 32a.
is attached between it and a pin 15c provided on the frame side plate 15a, and the exposure shutter 32 is biased clockwise (therefore, in the closing direction of the shutter 22) with the shaft 32b as the center of swing.

With this configuration, the state in which the upper housing 17 is opened upward (FIG. 3) and the state in which the upper housing 17 is closed will be described in order to perform maintenance of the copying machine main body such as jam removal.

First, as the upper housing 17 rotates downward, the lever 26 provided on the cartridge K also rotates downward. Finally, this lever 26 is connected to the protrusion 35.
As it hits the tip of and rotates further downward,
As previously mentioned, lever 26 is moved in the direction of arrow A (FIG. 4). This causes the swing arm 24 to swing counterclockwise about the shaft 25. Here, the arm 22, the transfer shutter 33. The swinging arm 24 has a four-bar link, and when the swinging arm 24 moves counterclockwise, the arm 22 rotates counterclockwise around the axis against the spring force of the spring 23, and the transfer shutter 33 moves to the right.

That is, the transfer shutter 33 is automatically retracted from the closed position where it covers the opening 31 to the open position where it does not interfere with the transfer. When the upper housing 17 further rotates downward, the lever 26 is further rotated, and the lever 27 is pulled downward to the right by the pin 26a on the lever 26, and the exposure shutter 32 is opened counterclockwise around the center 19a. The opening 3o for exposure opens (dotted line in Figures 7 and 8).
. Therefore, with the hinge 19 as the center of rotation, the main body C can be moved up and down in two directions.
Insert the process cartridge K into the upper housing 17 of the divided copying machine in an open state, and move the lever 26 in the direction of arrow A using the protrusion 35 provided on the lower housing 18 in conjunction with closing the upper and lower machine frames. By rotating it by a predetermined amount, the image exposure opening 3o and the transfer portion opening 31 are opened, and the copying apparatus can be put into a usable state.

Conversely, when the device body is closed, the upper housing 17
When rotated upward, the lever 26 and the protrusion 35 are disengaged, and the shutters 32 and 33 are automatically moved to the closed position covering the openings 3o and 31, respectively, by the spring force of the springs 23 and 28. do.

In this way, in this embodiment, since the exposure section shutter and the transfer shutter are automatically opened and closed in conjunction with the opening and closing operations of the copying machine main body, the surface of the photosensitive drum is automatically covered with the shutter when the main body is opened. The drum surface does not move or deteriorate due to exposure to light.

In each of the above embodiments, the cover is formed of a black opaque rigid body so that the surface of the photosensitive drum 3 is not exposed to light and is not damaged. However, the present invention is not limited thereto, and the cover may be formed of an opaque soft material (black polyester film, maltbrene, etc.) for the main purpose of blocking light (including reflection and absorption of light). Ru. Alternatively, it may be made of a transparent rigid body (such as transparent plastic) for the main purpose of preventing scratches on the drum surface.

Furthermore, even if the purpose is to block light.

The cover does not necessarily have to be made of an opaque material.
For example, the photosensitive layer may be made of a translucent material as long as it can block light in the wavelength range that causes deterioration. For example, in the case of an image forming method in which a magnetic latent image is formed on an insulating layer, the main purpose of the cover is to prevent damage such as scratches to the insulating layer.

The guide bar may be made of various known materials such as metals such as iron and aluminum, resins, and even wood. Furthermore, if a material having elasticity is used among these materials, the cover can be opened and closed more smoothly. Furthermore, if a shock-resistant material is selected from among these materials, the cartridge can be attached and detached without covering the photosensitive drum 3 with a cover and exposing the photosensitive drum 3.

Further, in this example, an example was shown in which an organic semiconductor photosensitive layer or a zinc oxide photosensitive layer was provided as an image carrier, but it is clear that the present invention is not limited to this, and other photosensitive layers can also be used. It is. Furthermore, the present invention is not limited to using a photosensitive layer as an image carrier,
It is also obvious that the present invention can also be applied to, for example, those using an insulating layer or the like. Further, the shape is not limited to a drum shape, and may be, for example, an endless belt suspended on a bobbin.

Further, the present invention is not limited to magnetic brush development, and for example, development methods such as cascade phenomenon, fur brush phenomenon, powder cloud development, etc. can be applied.

Also the cleaning method. The cleaning method is not limited to blade cleaning, and fur brush cleaning, φ roller cleaning, web cleaning, etc. can be applied.

Further, the imaging element is not limited to a short focus and small diameter imaging element array, and may be, for example, a normal lens or a bar lens.

Furthermore, the process for forming an image is not limited in any way; for example, the Carlson method-NP method (USP,
3,666.363) or the PIF method can also be applied.

Further, in this embodiment, an example is shown in which a developing device, a cleaner, a charger, etc. are integrated as process means in addition to the photosensitive drum in the process cartridge, but the present invention is not limited thereto.

For example, as shown in FIGS. 9(A) to 9(D), the cartridge K includes a developing device 5, a photosensitive drum 3 (FIG. 9(A)), a cleaner 14, and a photosensitive drum 3 (FIG. 9(A)) as process means.
FIG. 9(B)), charger 4, developer 5, and photosensitive drum 3 (
Figure 19. Note that the image carrier is not limited to the photosensitive drum 3 as described above.

That is, the process cartridge only needs to integrally include part or all of the image carrier and the process means. here,
In this embodiment, the process means that act on the image carrier include the array 2, the charger 4, the developer 5, the transfer discharger 8, the separation means 13, the cleaner 14, and the like.

As described above, according to the present invention, it is possible to provide an image forming apparatus or a process cartridge that can protect the image carrier with a shutter to prevent the image carrier from deterioration or damage such as scratches.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a copying machine loaded with a process cartridge to which the present invention is applied, FIG. 2 is a longitudinal sectional view of a process cartridge to which the present invention is applied, and FIG. 3 is a copying machine shown in FIG. 1. 4 is a side view showing the opening and closing mechanism of the shutter; FIG. 5 is a plan view showing the longitudinal direction of the exposure shutter that closes the opening for image exposure; FIG. 6 is a perspective view showing a transfer shutter that closes the opening of the transfer portion, FIG. 7 is a side view showing the exposure shutter in a closed state, and FIG. 8 is a side view showing the exposure shutter in an open state. 9 are schematic diagrams showing other embodiments of the process cartridge. In the figure, 3 is a photosensitive drum, 4 is a charger, 5 is a developer, 14 is a cleaner, 22 is an arm, 24 is a swinging arm, 26, 27 is a lever, 28 is a spring, 30 is an exposure opening, and 31 is a transfer amount r
'l, 32 is an exposure shutter, 33 is a transfer shutter, 35
is a protrusion, and K is a process cartridge.

Claims (2)

[Claims] (1) An image carrier, a process means acting on the image carrier, an exposure aperture for exposure to transmit image information to the image carrier, a closed position covering the exposure aperture, and a device evacuated from the closed position. a first protective shutter that can take an open position; a transfer opening for transferring the image formed on the image carrier onto a sheet; a closed position that covers the transfer opening; and an open position that is retracted from the closed position. and a second protective shutter that can take the above-mentioned first and
A process cartridge that is removably attached to a predetermined position inside an image forming apparatus, the process cartridge having: means for opening and closing a second protective shutter; (2) an image carrier, a process means that acts on the image carrier, an exposure aperture for exposure for transmitting image information to the image carrier, a closed position that covers the exposure aperture, and a closed position that is evacuated from the closed position; a first protective shutter that can take an open position; a transfer opening for transferring the image formed on the image carrier onto a sheet; a closed position that covers the transfer opening; and an open position that is retracted from the closed position. a second protective shutter that can take on the following characteristics; and an opening/closing means for opening and closing the first and second protective shutters; An image forming apparatus comprising: an operating member provided on the apparatus main body for operating the opening/closing means in accordance with the operation of attaching and detaching the image forming apparatus to a position.