JP2000221865A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inexpensive image forming device excellent in maintainability and capable of detecting the state that a unit consisting of an image carrier and its peripheral parts are set to a device main body and the state that the component parts of the unit are set to the unit with a simple configuration without increasing the number of parts. SOLUTION: In this device 50, the image carrier 1 and its peripheral parts are constituted as one unit 20, and the unit 20 is detachably attached to the device main body 50a. In this case, the device 50 is equipped with an attachment part 17 constituting the unit 20 and detachably attached to the unit 20 and a detection sensor 13 provided in the main body 50a and detecting the state that the unit 20 is set to the main body 50a. The sensor 13 functions also as a sensor for detecting the state that the part 17 is attached to the unit 20.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic image forming apparatus such as a copier, a printer, a facsimile, and the like.

[0002]

2. Description of the Related Art Generally, in an image forming apparatus using an electrophotographic process, an electrostatic latent image corresponding to a document image is formed on a surface of a photosensitive member (image carrier) charged to a predetermined polarity in advance. Is done. This electrostatic latent image is developed by a developing unit provided at a predetermined position around the photoconductor. That is, the electrostatic latent image is developed and visualized by the charged fine powder toner supplied from the developing unit. The toner image formed on the photoreceptor reaches the transfer section by rotation of the photoreceptor,
The image is transferred onto a transfer material (recording paper) conveyed to the transfer unit. Thereafter, the toner image transferred to the transfer material is fixed to the transfer material in a fixing unit.

A general image forming apparatus is designed so that a unit having a lower durability than the apparatus main body can be replaced (removable with respect to the apparatus main body). In the event of a failure or the like, the unit can be replaced or maintained by a service person or a user.

A unit detachably mounted on the apparatus main body includes a unit including a photoreceptor and its peripheral parts (hereinafter, referred to as a PCU (image forming unit)), or a unit that thermally transfers a toner image to a transfer material. There is a fixing device for fixing the image on the sheet. In particular, the PCU includes a photoreceptor, charging means for charging the surface of the photoreceptor, cleaning means for removing residual toner on the photoreceptor, and a transfer member (color image) for transferring a toner image on the photoreceptor to a transfer material. (Including an intermediate transfer member necessary to obtain the toner image), a waste toner cartridge for accommodating waste toner, and the like.

As described above, in an image forming apparatus in which various units are detachably attached to the apparatus main body, various types of units are provided to ensure the safety of an operator or to perform image formation in a normal state. A sensor is provided for detecting whether the unit is securely mounted on the apparatus main body. Such a detection sensor functions as, for example, an interlock switch, and constitutes an interlock mechanism for forcibly stopping the operation of the device when the device does not satisfy a preset condition.

[0006]

As described above, the PC
In an image forming apparatus in which U is detachably attached to the apparatus main body, the presence or absence of a PCU (PCU
(A set state) is provided. Further, when the components (for example, charging means) constituting the PCU are detachable from the PCU, the PCU
Also, a sensor for detecting the set state of the component (forgetting the component to the PCU (presence or absence)) is required. That is, if the unit is detachable from the apparatus main body, or if its components are detachable from the unit, the maintainability of the apparatus is improved,
On the other hand, the number of parts such as sensors increases.

In recent years, as the size and cost of image forming apparatuses have been reduced, it has been required to simplify the structure of the image forming apparatus and reduce the number of parts. The challenge is how to achieve both low cost and low cost.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an apparatus having a simple structure without increasing the number of parts and comprising an image carrier and its peripheral parts. It is an object of the present invention to provide an inexpensive and excellent maintainability image forming apparatus capable of detecting a set state of a main body and a set state of its component parts with respect to the unit.

[0009]

According to a first aspect of the present invention, an image carrier is constructed as a single unit together with its peripheral parts, and this unit is attached to and detached from an apparatus main body. In an image forming apparatus that is capable of being mounted, a detachable part that constitutes the unit and that is detachably attached to the unit, and a detection sensor that is provided in the apparatus main body and detects a set state of the unit with respect to the apparatus main body. Wherein the detection sensor also serves as a sensor for detecting a state of attachment of the detachable part to the unit.

According to the first aspect of the present invention, one set sensor can detect the set state of two device components such as a unit and a detachable part, so that the maintenance of the device can be performed without increasing the number of parts. Can be improved,
Further, safety of image formation can be ensured.

The invention described in claim 2 is the first invention.
In the invention described in (1), the detachable component is a charging unit that charges a surface of the image carrier.

According to the second aspect of the present invention, the detection of the unit and the detection of the charging means can be performed by one detection sensor.

[0013] The invention described in claim 3 is the first invention.
Or in the invention according to claim 2, the detection sensor is:
The unit is provided at a position in contact with the detachable part in a state where the unit is positioned at a predetermined set position in the apparatus main body.

According to the third aspect of the present invention, it is possible to efficiently detect the set state of two device components such as a unit and a detachable part.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 schematically shows an image forming apparatus 50 according to an embodiment of the present invention. As shown in the figure, the image forming apparatus 50 is a color electrostatic image forming apparatus including an intermediate transfer belt 4 as an intermediate transfer body. Color scanner for converting to color image data (not shown)
And a laser writing unit (not shown) as exposure means. The writing optical unit converts the color image data from the color scanner into an optical signal, performs optical writing corresponding to the original image, and forms an electrostatic latent image on the surface of the belt-shaped photoconductor 1 as an image carrier. Form an image.

The apparatus main body 50a of the image forming apparatus 50
Inside, a unitized process cartridge (hereinafter, referred to as a PCU (image forming unit)) 20 is detachably mounted. As will be described later with reference to FIG. 2, the PCU 20 includes a photoconductor 1, a charging charger unit (charging unit) 17 for charging the surface of the photoconductor 1, transfer units 14 and 15, including the intermediate transfer belt 4, the photoconductor 1, and an intermediate unit. The cleaning devices 52 and 53 for removing the residual toner on the transfer belt 4, the waste toner cartridge 16, the waste toner conveying passage 7, and the like are integrally incorporated, and are configured to be replaceable at the end of life. In this case, the charger unit 17 is detachably attached to the PCU 20.

Further, in order to facilitate replacement of the PCU 20 and a developing device, which will be described later, and jam clearance, an apparatus main body 50 is provided.
A part of the front frame 30 is rotated about the support shaft 31 to open the inside of the apparatus main body 50a as shown in FIG.

The detailed configuration of the PCU 20 is shown in FIG. As shown in the figure, the photoconductor 1 is rotatably supported by a driving roller 3 and a driven roller 2, and rotates clockwise, for example, as indicated by an arrow in the figure. Around the photoconductor 1, a cleaning device 53 having a cleaning blade 10, a transport screw 11, and a waste toner cartridge 16, a charging charger unit 17, and the intermediate transfer belt 4 are arranged.

Although not shown, a laser beam emitted from the laser writing unit is located on the device main body 50a side at a position downstream of the charging charger unit 17 with the PCU 20 set in the device main body 50a. Selected development of an irradiating optical writing unit and a rotary developing device (hereinafter, referred to as a multi-color developing device) as a developing unit (supplying toner to an electrostatic latent image on the photoconductor 1 for development). And a black developing unit containing black toner.

The intermediate transfer belt 4 is rotatably supported by a driving roller 5 and a driven roller 6. A transfer brush (bias means) 14 is provided on the back surface of the intermediate transfer belt 4.
The toner image on the photoconductor 1 is transferred to the surface of the intermediate transfer belt 4 by the bias unit 14. A cleaning device 52 for cleaning the surface of the intermediate transfer belt 4 and a transfer roller 15 are provided near the drive roller 5 that supports the intermediate transfer belt 4. The cleaning device 52 has a cleaning blade 8 and a transport screw 9, and the cleaning blade 8 can be freely moved toward and away from the intermediate transfer belt 4 via a not-shown arm.

When the toner image is transferred from the photoreceptor 1 to the intermediate transfer belt 4, the cleaning blade 8 separates from the intermediate transfer belt 4 and transfers the transfer material (a recording medium such as paper or plastic) from the intermediate transfer belt 4. After the toner image is transferred to the intermediate transfer belt 4, the residual toner on the intermediate transfer belt 4 is scraped off.

The transfer material onto which the toner image is transferred is sent out from a paper feeding device (paper feeding cassette) (not shown) provided on the apparatus main body 50a side via a paper feeding roller and a conveying roller pair, and is sent by a registration roller pair. At a predetermined timing, it is fed into a nip portion between the intermediate transfer belt 4 and the transfer roller 15. On the other hand, before the transfer material is conveyed, toner images of a predetermined color are sequentially formed on the photosensitive member 1, and each time the toner images of each color are sequentially transferred to the same position on the intermediate transfer belt 4. (The image is transferred one by one every time the intermediate transfer belt 4 makes one rotation.) In this case, the photoconductor 1 is cleaned for each color to prepare for the formation of the next color. The multi-color toner images sequentially transferred to the intermediate transfer belt 4 and superimposed are transferred by the action of the transfer roller 15.
The image is collectively transferred to a transfer material sent to a nip portion between the intermediate transfer belt 4 and the transfer roller 15. The transfer material onto which the toner images of a plurality of colors are collectively transferred is then sent to a fixing device (not shown) on the side of the apparatus main body 50a, where the toner image is fixed. Is discharged.

The waste toner scraped from the photoreceptor 1 and the intermediate transfer belt 4 by the cleaning blades 8 and 10 passes through the waste toner transport passage 7 by transport screws 9 and 11 provided in the cleaning devices 52 and 53. It is conveyed and stored in the waste toner cartridge 16. Further, the waste toner cartridge 16 is appropriately replaced in accordance with the amount of stored waste toner.

As shown in FIG. 1, the PCU having the above configuration
Reference numeral 20 denotes a PC rotatably supported by the apparatus main body 50a.
It is set in the device main body 50a via the U guide device 18. That is, when setting the PCU 20 in the apparatus main body 50a, first, as shown in FIG. 3, the front frame 30 is opened to expose the inside of the apparatus main body 50a. Next, in this state, the PC is
The U20 is mounted on the guide device 18. And PCU
The PCU 20 is rotated to the set position (the position shown in FIG. 1) where the image forming can be performed by rotating the guide device 18 in the direction G in FIG.
Close 0. On the other hand, when the PCU 20 is to be detached from the apparatus main body 50a for replacement or maintenance, the above operation may be performed in reverse.

As shown in FIGS. 1 and 3,
On the device body 50a side, the PCU 20 is positioned at the set position in the device body 50a (the state of FIG. 1).
A detection sensor 13 for detecting a setting state of the PCU 20 with respect to the apparatus main body 50a is provided at a portion facing the charging charger unit 17 (specifically, below the charging charger unit 17). The detection sensor 13 is located at a set position where image formation is possible.
When the switch is set correctly, the switch portion is formed as a push-type sensor that is pressed by the charging charger unit 17 and set to the ON state. Therefore, the charging unit 17 is connected to the PCU 20
If it is not attached to the PC,
Even if U20 is set correctly in the setting position,
The detection sensor 13 does not operate (is not turned on). That is, the detection sensor 13 is connected to the PCU with respect to the apparatus main body 50a.
In addition to detecting the set state of PC 20 (presence / absence of PCU in apparatus main body 50a), it also serves as a sensor for detecting the set state of charged charger unit 17 to PCU 20 (forgetting to install charged charger unit 17 to PCU 20 (presence or absence)). ing. for that reason,
If the detection sensor 13 is set to the ON state, the PCU 20
And the charging charger unit 17 is an apparatus main body 50a.
You can see that is set correctly. If the detection switch 13 is in the OFF state, the PCU 20 itself may not be set in the apparatus main body 50a, or it may be that the PCU 20 is in the apparatus main body 50a but the charging charger unit 17 is not attached to the PCU 20. I understand.

In the present embodiment, the detection sensor 1
The setting state of the PCU 20 and the charging charger unit 17 detected via the control unit 3 is notified to the user by, for example, a notification unit connected to the detection sensor 13.
The notification means comprises, for example, a liquid crystal monitor and a lamp. When the detection sensor 13 detects a setting failure of the PCU 20 and the charging charger unit 17, the fact is displayed on the liquid crystal monitor or the lamp is turned on.

When the detection sensor 13 is in the OFF state, the PCU 20 and other devices may be electrically disconnected from the power supply (motor, laser, etc.) of the apparatus main body 50a. That is, when the detection sensor 13 functions as an interlock switch, and the device does not satisfy a preset condition (when the PCU 20 and the charging charger unit 17 are not set correctly).
Alternatively, the operation of the device may be forcibly stopped. In this case, the user closes the front frame 30 without attaching the PCU 20 or the charging unit 17 to the apparatus main body 50a by mistake, and closes the apparatus main body 50a.
Even if the power is turned on, the copying operation is not started, and the safety of the operation is ensured.

As described above, in the image forming apparatus 50 of the present embodiment, the PCU for the apparatus main body 50a is used.
The detection sensor 13 for detecting the set state of the PCU2 is the PCU2
The sensor also serves as a sensor for detecting the set state of the charging charger unit 17 with respect to 0. That is, PCU20
The sensor for detecting the presence or absence of the charging charger unit 17 and the sensor for detecting the presence or absence of the charging charger unit 17 are commonly used. Therefore, PCU 20
And the set state of two units such as the charging unit 17 can be detected. Further, in the image forming apparatus 50 of the present embodiment, the PCU 20 is an apparatus main body 50a.
To the PCU2
A charging charger unit 17 is detachably attached to the unit 0. Therefore, the maintainability of the device is improved.

As described above, the image forming apparatus 5 of the present embodiment
No. 0 increases the number of components such as sensors because a single sensor can detect the set state of the plurality of detachable units while improving maintainability by configuring a plurality of units detachably. It is not necessary to perform the above, and it is possible to achieve both improvement of the maintainability of the apparatus and downsizing (low cost).

In the present embodiment, the sensor 13 for detecting the set state of the PCU 20 also functions as a sensor for detecting the set state of the charging charger unit 17 with respect to the PCU 20, but the set state of other components constituting the PCU 20 is set. May be detected. That is, components other than the charging charger unit 17 may be made detachable from the PCU 20, and the setting state of the detachable component with respect to the PCU 20 may be detected by the detection sensor 13.

In this embodiment, the PCU 20
The device main body 50a is rotated by rotating the guide device 18.
The PCU 20 may be arranged at the set position by inserting the PCU 20 directly into the apparatus main body 50a without the intervention of the guide device 18. Of course, even in this case, the detection sensor 13
Is provided at a position facing the charging charger unit 17 when the PCU 20 is positioned at the set position in the apparatus main body 50a (the state shown in FIG. 1).

In this embodiment, the detection sensor 1
3 is a push type, but is not limited thereto, and may be, for example, a reflection type.

[0034]

According to the first aspect of the present invention, a single detection sensor can detect a set state of two device components such as a unit and a detachable part, so that maintenance of the device can be performed without increasing the number of parts. Performance can be improved, and the safety of image formation can be ensured.

According to the second aspect of the present invention, the detection of the unit and the detection of the charging means can be performed by one detection sensor.

According to the third aspect of the present invention, it is possible to efficiently detect the set state of two device components such as a unit and a detachable part.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of an image forming apparatus according to an embodiment of the present invention.

FIG. 2 shows a P detachably mounted on the image forming apparatus of FIG.
It is a detailed view of a CU.

FIG. 3 is a diagram for explaining an operation of attaching and detaching a PCU to and from the apparatus main body of the image forming apparatus.

[Explanation of symbols]

Reference Signs List 1 photoconductor (image carrier) 13 detection sensor 17 charging charger unit (detachable part, charging means) 20 PCU (unit) 50 image forming apparatus 50a apparatus main body

Claims (3)

[Claims] 1. An image forming apparatus in which an image carrier and its peripheral parts are configured as one unit, and this unit is detachably mounted to an apparatus main body. And a detection sensor provided on the apparatus main body and configured to detect a setting state of the unit with respect to the apparatus main body, wherein the detection sensor detects the mounting state of the detachable part with respect to the unit. An image forming apparatus characterized in that the image forming apparatus also serves as a sensor that performs the operation. 2. The image forming apparatus according to claim 1, wherein the detachable component is a charging unit that charges a surface of the image carrier. 3. The apparatus according to claim 1, wherein the detection sensor is provided at a position where the unit comes into contact with the detachable part in a state where the unit is positioned at a predetermined set position in the apparatus main body. 3. The image forming apparatus according to 2.