JPH04181953A - Image forming device - Google Patents

Abstract

PURPOSE:To simply carry out jamming processing, the cleaning of the optical system of an exposing unit, the replenishing of toner to a developing unit, etc., by providing a belt frame, a photosensitive body frame capable of moving, and an turnable exposing unit frame. CONSTITUTION:The photosensitive body frame 24 to which, at least, the developing unit and a photosensitive drum are attached, is supported so as to be freely moved in a vertical direction, on the upper part of the belt frame 25 to which an image transfer belt 3 is attached, and an exposing unit frame 26 to which, at least, the exposing unit 7 is attached is pivotally supported so as to be turned in the vertical direction, on the upper part of the photosensitive body frame 24. Therefore, the photosensitive body frame 24 is displaced upward, to expose the image transfer belt 3 attached to the belt frame 25, so that the jam processing, etc., are simply carried out. The exposing unit frame 26 is turned upward, to expose the developing unit attached to the photosensitive body frame 24. The exposing unit attached to the exposing unit frame 26, etc., so that the cleaning of the optical system of the exposing unit, the replenishing of the toner to the developing unit, etc., are simply carried out.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an image forming apparatus in which at least one printing station is arranged on a freely rolling endless image transfer belt.

2. Description of the Related Art In recent years, electrophotography has been developed as one of the electrostatic image forming methods. In this method, an electrostatic latent image is formed on a charged photoreceptor by optical scanning or the like, and this electrostatic latent image is developed with charged toner and transferred to a recording medium. An image forming apparatus using such an electrophotographic method includes, for example, a printing station in which at least a charging device, an exposing device, and a developing device are sequentially arranged facing each other on the circumferential surface of a photosensitive drum.
It has been proposed that at least one printing station is arranged above an endless belt-shaped image transfer belt which is stretched so as to be able to roll freely.

Therefore, a conventional example of an image forming apparatus having such a structure is described in the seventh section.
This will be explained based on the diagram. This image forming apparatus 1 is wired for color printing, and is located at a position facing the upper surface of a paper conveyance belt 3, which is an endless belt-shaped image conveyance belt stretched approximately horizontally by a pair of rotating rollers 2. Four printing stations 4, to 44 are arranged in succession. Here, these printing stations 4. 44 is a photosensitive drum 9 on which a toner cleaner 5, a charger 6, an optical scanning device 7 as an exposure device, a developing device 8, etc. are arranged facing each other on the circumferential surface,
It has a structure in which it faces a transfer device (not shown) via the paper conveyance belt 3. Further, the developer 8 is connected to each printing station 4. Color toners (not shown) such as yellow, magenta, cyan, and black are stored every .about.44. At the front and rear ends of the paper conveyance belt 3, a paper feeding device 10 storing printing paper (not shown) and a fixing device 11 which also serves as a paper ejecting device are arranged to face each other.

In this configuration, in the image forming apparatus 1, the printing paper supplied from the paper feeding device 10 is transferred to the paper conveying belt 3.
is electrostatically attracted and transported. Therefore, each printing station 4. is driven in synchronization with the movement of the printing paper. ~4
4, the peripheral surface of the photosensitive drum 9 charged by the corona discharge of the charger 6 is selectively neutralized by optical scanning of the optical scanning device 7 to form an electrostatic latent image, and this electrostatic latent image is transferred to the developing device 8. A toner image is formed by developing with toner supplied from the toner.

The printing paper, on which toner images are sequentially formed in this manner, is processed at each printing station 4. ~4. Each time, monochrome toner images of each color are printed one on top of the other to form a color toner image. Therefore, the printing paper on which this toner image is formed is conveyed from the paper conveyance belt 3 to the fixing device 11, where it is heated under pressure and discharged to the outside of the device with the toner image fixed, thereby completing color printing. .

Here, Utility Model Application Publication No. 63-107444 and Utility Model Application No. 63-107444
In the image forming apparatus disclosed in Publication No. 107469, etc., a photosensitive drum, which is part of a printing station, a toner cleaner, and a charger are integrally formed into one process unit, and a lower part where a paper conveyance path is formed. The process unit is detachably attached to an upper frame that is rotatably supported in the vertical direction by the frame.

Problems to be Solved by the Invention In the image forming apparatus disclosed in the above-mentioned publication, the main parts of the printing station are unitized and mounted on a rotatable upper frame located on the paper conveyance path, so that jam handling and developing equipment can be easily handled. This makes maintenance work such as replacement of equipment easier and improves equipment productivity.

However, in the image forming apparatus disclosed in the above publication, the exposure device is integrally provided inside the upper frame to which the process unit is attached, so maintenance work such as cleaning the optical system of this exposure device is difficult. It has become.

Furthermore, in the image forming apparatus disclosed in the above-mentioned publication, a mechanism that requires driving power, such as a charger, is provided in the process unit, so a means for supplying power to the process unit, which is detachable from the upper frame, is provided. It is necessary to provide However, the above-mentioned publication does not disclose any specific means for easily and reliably realizing such power supply. If the means for supplying power as described above is formed by a removable connector, etc., in the above-mentioned image forming apparatus, for example, when cleaning the optical system of the exposure device or replenishing toner to the developing device, Since it is also necessary to remove the process unit, connection failures are likely to occur due to frequent attachment and detachment.

Means for Solving the Problems The invention as set forth in claim 1 provides a printing station in which at least a charging device, an exposing device, and a developing device are sequentially arranged facing each other on the circumferential surface of a photosensitive drum, and the printing station is provided so as to be freely rollable. In an image forming apparatus in which at least one printing station is arranged above an endless belt-shaped image transfer belt, a belt frame to which the image transfer belt is attached is provided, and at least a developing device of the printing station is provided at a position facing the belt frame from above. A photoreceptor frame, to which a photoreceptor frame and a photoreceptor drum are attached, is vertically movably supported, and at least an exposure device of a print station is attached to an exposure frame, which is attached to a position facing the photoreceptor frame from above, and is rotated in the vertical direction. Pivotally supported for free movement.

The invention according to claim 2 provides a printing station in which at least a charging device, an exposing device, and a developing device are sequentially arranged facing each other on the circumferential surface of a photosensitive drum, and an endless belt-shaped image transfer belt stretched so as to be freely rollable. In an image forming apparatus for color printing in which a plurality of printing stations are disposed above, a belt frame to which an image transfer belt is attached is provided, a printing unit including at least a developing unit of the printing station and a photosensitive drum is provided, and this printing The unit forms a photoreceptor frame that is detachably attached from above, supports the photoreceptor frame in a vertically movable manner at a position facing the belt frame from above, and supports the photoreceptor frame at a position facing the photoreceptor frame from above. At least the exposure device frame to which the exposure device of the printing station was attached was pivotally supported so as to be freely rotatable in the vertical direction.

The invention according to claim 3 provides a power supply terminal connected to the main body power source on the photoreceptor frame, and a connection terminal connected to at least a charger or a developing device and detachably connected to the connection terminal of the photoreceptor frame. installed in the printing unit.

The invention according to claim 1 supports a photoreceptor frame on which at least a developing device and a photoreceptor drum are attached above a belt frame on which an image transfer belt is attached, so as to be movable in the vertical direction. Since the exposure device frame, on which at least an exposure device is attached above, is rotatably supported in the vertical direction, the image transfer belt attached to the belt frame is exposed by displacing the photoreceptor frame upward. It is easy to clear jams, etc., and by rotating the exposure unit frame upward, the developer attached to the photoreceptor frame and the exposure unit attached to the exposure unit frame are exposed. Cleaning of the optical system and replenishment of toner to the developing device can be easily performed.

According to the second aspect of the invention, a printing unit containing at least a developing device and a photosensitive drum forms a photosensitive frame to which it is detachably attached from above, and the photosensitive frame is connected to a belt frame to which an image transfer belt is attached. The exposure device frame, on which at least an exposure device is attached, is supported above the photoreceptor frame so as to be movable in the vertical direction, and the exposure device frame, on which at least an exposure device is attached, is pivotably supported in the vertical direction. There is no need to remove the printing unit from the photoconductor frame when performing maintenance work such as cleaning the photoconductor and replenishing toner to the developer, reducing the number of times the printing unit is connected to and disconnected from the power supply of the main unit, thereby reducing contact failures. In addition, it is possible to easily replace only the printing unit of a color whose consumption amount is excessive.

The invention according to claim 3 provides a power supply terminal connected to the main body power source on the photoreceptor frame, and a connection terminal connected to at least a charger or a developing device and detachably connected to the connection terminal of the photoreceptor frame. By providing this in the printing unit, the printing unit and main body power supply are automatically connected simply by mounting the printing unit on the photoreceptor frame.

Embodiment An embodiment of the present invention will be explained based on FIGS. 1 to 6. Note that the same parts as those in the image forming apparatus 1 described above are given the same names and symbols, and the description thereof will be omitted. First, in the color printer 12 which is the image forming apparatus of this embodiment, the third
As illustrated in FIGS. 5 to 5, a printing unit 14 is provided by arranging a toner cleaner 5, a charger 6, and a developer 8 facing each other on the outer periphery of the photosensitive drum 9 and attaching them to a unit case 13. Here, for example, ABS (
A crylonitrile-B utadiene
As illustrated in FIG. 3, the unit case 13 made of resin or the like has legs 15 and handles 16 protruding from the bottom and upper sides of both ends.
A connecting terminal 17 connected to the components 6 and 8 is formed on the bottom surface of one of these handles 16. In addition, in this color printer 12, as illustrated in FIG. 4, a guide member 18 and a guide bin 19 each having a plate spring curved into a hairpin shape are provided on the upper and lower sides of the vertically elongated developing device 8.
A clamp 22 for holding the guide bin 19 is rotatably supported on the unit case 13 in which a guide bin 20 and a groove 21 are formed with which these members 18 and 19 engage. and is biased by a spring 23.

In this color printer 12, as illustrated in FIG. The exposure device frame is supported by a link mechanism (not shown) or the like on the attached belt frame 25 so as to be vertically movable, and the optical scanning device 7 is attached to the unit frame 24. A frame 26 is rotatably supported. Here, the unit frame 24 is provided with a connecting terminal 27 which is connected to the connecting terminal 17 of the printing unit 14 so as to be able to freely come into contact with and separate from it, as illustrated in FIG.
This connection terminal 27 is connected to a main body power source (not shown). Further, as illustrated in FIG. 6, a slide shaft 29 biased downward by a spring 28 is attached to the rotation frame 26 so as to be slidable in the vertical direction, and this slide shaft 29 is connected to the printing unit. 1
4 handles 16 are pressed and held against the unit frame 24.

With this configuration, the color printer 12 prints color images in the same manner as the image forming apparatus 1 described above.

Here, in this color printer 12, a unit frame 24 on which a printing unit 14 is attached is supported on a belt frame 25 on which a paper conveyance belt 3 is attached so as to be able to approach and separate, and an optical scanning device 7 is mounted on this unit frame 24.
Since the rotary frame 26 to which the unit frame 24 is attached is supported so as to be openable and closable, displacing the unit frame 24 upward can easily clear jams, etc., and by opening and closing the rotary frame 26, light scanning can be performed. Cleaning of the optical system of the device 7, replenishment of toner, etc. can be easily performed. In other words, in this color printer 12, when performing maintenance work as described above, the unit frame 24
Since there is no need to remove the printing unit 14 from the printer, the number of times the connection terminals 17 and 27 are connected and separated is reduced, and poor contact is prevented.

In addition, in this color printer 12, simply by mounting the printing unit 14 on the unit frame 24, the connection terminal 17
．． 27 is automatically connected, operations such as replacing the printing unit 14 are easy and erroneous operations are prevented.Furthermore, this connection is maintained in good condition by pressing and holding the slide shaft 29, so that the equipment The performance is stable.

Furthermore, in this color printer 12, the main parts of the printing station 4 are unitized into the printing unit 14, so that, for example, only the printing unit 14 of a color that consumes an excessive amount can be easily replaced.

Moreover, in this color printer 12, the unit frame 24 is configured to move vertically parallel to the belt frame 25, so that the developing device 8 in the printing unit 14 is always maintained horizontally, thereby improving the toner supply performance. is stable.

In this embodiment, the color printer 12 in which four printing stations 48 to 44 are arranged on the paper conveyance belt 3 is illustrated as an image forming apparatus, but the present invention is not limited to the above structure. It is also applicable to a monochromatic image forming apparatus (not shown) in which one printing station 4 is arranged on the conveyor belt 3. Further, in this embodiment, the color printer 12 that uses the paper transport belt 3 as the image transport belt is exemplified, but the present invention is not limited to the above format. Forming devices and the like are also possible.

Effects of the Invention The invention described in claim 1 provides a printing station in which at least a charging device, an exposing device, and a developing device are sequentially arranged facing each other on the circumferential surface of a photosensitive drum, and an endless belt-shaped image rollably stretched. In an image forming apparatus in which at least one printing station is arranged above a transfer belt, a belt frame to which the image transfer belt is attached is provided, and at least a developing device and a photosensitive drum of the printing station are arranged at positions facing the belt frame from above. A photoreceptor frame with a photoreceptor mounted thereon is supported vertically movably, and at a position facing the photoreceptor frame from above, an exposure device frame with at least an exposure device of a print station is mounted on an axis rotatably vertically. By supporting the photoreceptor frame, the image transfer belt attached to the belt frame is exposed by moving the photoreceptor frame upward, making maintenance work such as jam removal easier. By moving it, the developing device attached to the photoconductor frame and the exposing device attached to the exposure device frame are exposed, so maintenance work such as cleaning the optical system of the exposure device and replenishing toner to the developing device is carried out. This method has the advantage of being easy to perform and providing an image forming apparatus with a simple structure and good maintainability.

The invention according to claim 2 provides a printing station in which at least a charging device, an exposing device, and a developing device are sequentially arranged facing each other on the circumferential surface of a photosensitive drum, and an endless belt-shaped image transfer belt stretched so as to be freely rollable. In an image forming apparatus for color printing in which a plurality of printing stations are disposed above, a belt frame to which an image transfer belt is attached is provided, a printing unit including at least a developing unit of the printing station and a photosensitive drum is provided, and this printing The unit forms a photoreceptor frame that is detachably attached from above, supports the photoreceptor frame in a vertically movable manner at a position facing the belt frame from above, and supports the photoreceptor frame at a position facing the photoreceptor frame from above. At least the exposure frame, to which the exposure unit of the printing station is attached, is rotatably supported in the vertical direction, so that by displacing the photoreceptor frame upward, the image transfer belt attached to the belt frame is exposed. Maintenance work such as jam removal can be easily performed, and by rotating the exposure unit frame upward, the developer attached to the photoreceptor frame and the exposure unit attached to the exposure unit frame can be cleaned. Therefore, maintenance work such as cleaning the optical system of the exposure unit and replenishing toner to the developing unit can be easily performed.Furthermore, when performing maintenance work as described above, the printing unit can be removed from the photoreceptor frame. Since there is no need
The number of times the printing unit is connected to and disconnected from the main power supply is reduced, preventing contact failures, and it is also easy to replace only the printing unit of a color that consumes too much, improving maintainability. This has the advantage that it is possible to implement an image forming apparatus with good performance and stable performance.

The invention according to claim 3 provides a power supply terminal connected to the main body power source on the photoreceptor frame, and a connection terminal connected to at least a charger or a developing device and detachably connected to the connection terminal of the photoreceptor frame. By installing this in the printing unit, the printing unit and main power supply are automatically connected just by mounting the printing unit on the photoconductor frame, making it easy to replace the printing unit and prevent connections caused by operator error. This has the effect of preventing the occurrence of defects.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing an embodiment of the present invention, Fig. 2 is a vertical side view, Fig. 3 is an exploded perspective view of main parts, Fig. 4 is a longitudinal side view, Fig. 5 is a perspective view, and Fig. 6 is a perspective view showing an embodiment of the present invention. The figure is an enlarged perspective view of the main part, and FIG. 7 is a longitudinal sectional side view showing a conventional example. 3... Image transfer belt, 4... Printing station,
6... Charger, 7... Exposure device, 8... Developer, 9
...Photosensitive drum, 12... Image forming device, 14...
Printing unit, 17.27... Connection terminal, 24...
Photoreceptor frame, 25...Belt frame, 26...
・Exposure device frame Applicant Tokyo Electric Co., Ltd. 171 Figure old zb Word 1 Fuji 1F L-Ha 1 Bada, 711b Figure

Claims (1)

[Claims] 1. A printing station is provided in which at least a charging device, an exposing device, and a developing device are arranged facing each other on the circumferential surface of the photosensitive drum,
In an image forming apparatus in which at least one printing station is arranged above an endless belt-shaped image transfer belt that is stretched so as to be able to roll freely, a belt frame to which the image transfer belt is attached is provided, and the belt frame is attached to the belt frame from above. A photoreceptor frame on which at least a developer and a photoreceptor drum of the printing station are mounted is supported movably in the vertical direction at opposing positions, and at least an exposure unit of the printing station is provided at a position facing the photoreceptor frame from above. An image forming apparatus characterized in that an exposure device frame to which an exposure device frame is attached is pivotally supported for vertical rotation. 2. A printing station is provided in which at least a charging device, an exposing device, and a developing device are arranged facing each other on the circumferential surface of the photosensitive drum,
In an image forming apparatus for color printing, in which a plurality of printing stations are disposed above an endless band-shaped image transfer belt stretched so as to be freely rolling, a belt frame to which the image transfer belt is attached is provided, and at least the printing A printing unit containing a station developing device and a photosensitive drum is provided, the printing unit forms a photosensitive frame to which the printing unit is removably attached from above, and the photosensitive frame is placed at a position facing the belt frame from above. The exposure device frame is supported so as to be movable in the vertical direction, and an exposure device frame to which at least an exposure device of the printing station is attached is pivotably supported in a position facing the photoreceptor frame from above so as to be freely rotatable in the vertical direction. Image forming device. 3. A power supply terminal connected to the main power supply is provided on the photoreceptor frame, and a connection terminal is provided on the printing unit, which is connected to at least a charger or a developing device and is removably connected to the connection terminal of the photoreceptor frame. The image forming apparatus according to claim 2, characterized in that: