JP2002149014A - Image forming device and process cartridge - Google Patents

Abstract

PROBLEM TO BE SOLVED: To steadily perform identification of an individual photoreceptor drum and detection of cumulative number of rotation of the photoreceptor drum by allowing it to have an inexpensive structure. SOLUTION: A bar code 40 is provided on an image non-formation area 7a of the photoreceptor drum 7 in order to identify an individual photoreceptor drum 7 and detect the cumulative number of rotations of the photoreceptor drum 7. Also, a reflective photoelectric sensor 41 is disposed on a bearing 4c of a transfer roller 4 so as to face the bar code 40 of the photoreceptor drum 7. When the bar code 40, which moves with the rotation of the photoreceptor drum 7, passes above the reflective photoelectric sensor 41, information of the bar code 40 is detected by the reflective photoelectric sensor 41. Thus, by using the single reflective photoelectric sensor 41, the identification of the individual photoreceptor drum 7 and the detection of the cumulative number of the rotation of the drum 7 can be steadily performed in an inexpensive structure.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus such as a copying machine, a printer, a facsimile, etc., which forms an image using an electrophotographic system or an electrostatic recording system, and a photoconductor, at least a charging unit and a developing unit. The present invention relates to a process cartridge including at least one of them and detachably attached to an image forming apparatus main body.

[0002]

2. Description of the Related Art In an image forming apparatus such as a copying machine, a printer, a facsimile or the like using an electrophotographic system, a surface of a drum type electrophotographic photosensitive member (hereinafter, referred to as a photosensitive drum) as an image carrier is charged by a charging device. The surface of the charged photosensitive drum is exposed by an exposure device to form an electrostatic latent image. Then, the electrostatic latent image is developed by a developing device to form a toner image, and the toner image is transferred to a transfer material such as paper by a transfer device to form an image. The transfer residual toner remaining on the surface of the photosensitive drum after the transfer is removed by a cleaning device.

In the above-described image forming apparatus, the photosensitive drum, the charging device, the developing device, and the cleaning device are integrally formed as a cartridge so that the user can easily replace and maintain consumables such as the photosensitive drum and toner. In addition, a process cartridge that can be attached to and detached from the image forming apparatus main body is employed.

Incidentally, the photosensitive drum has a functional life due to an electrical action such as charging repeatedly received in an image forming operation and a mechanical action such as rubbing with a cleaning blade as a cleaning device. Therefore,
A means for detecting the endurance life of the photosensitive drum and notifying the user of the replacement time is required.

In order to manage the life of the photosensitive drum, two pieces of information, i.e., identification of the photosensitive drum and integration of the number of rotations of the drum, are necessary in consideration of the fact that the process cartridge is replaced with the image forming apparatus main body in the middle of the life. Become.

As a method for identifying the individual photosensitive drums, a method is provided in which a barcode is provided in a process cartridge and barcode identification information is read by a sensor provided on the image forming apparatus main body side during mounting operation (for example, Japanese Patent Application Laid-Open No. Hei 8-171329). And a method of mounting a memory chip on a process cartridge and reading identification data in a wired or wireless manner.

As a method of counting the accumulated number of rotations of the photosensitive drum, there is a method of counting the number of rotations of a drum drive shaft of the image forming apparatus main body by using a sensor.

[0008]

However, in the above-described method of identifying the individual photosensitive drums and counting the total number of rotations of the photosensitive drum according to the above-described conventional method, detection of individual identification of the photosensitive drums and calculation of the total number of rotations of the photosensitive drums are performed. Since each individual sensor is used for detection, there is a problem that installation space, wiring, and adjustment of these sensors are required, and the cost is increased.

SUMMARY OF THE INVENTION An object of the present invention is to provide an image forming apparatus and a process cartridge capable of stably performing individual identification of a photosensitive drum and detection of an integrated rotation speed with an inexpensive configuration.

[0010]

In order to achieve the above object, the present invention provides an image forming apparatus for forming an image by transferring a toner image formed on a photoreceptor detachable to an apparatus main body onto a transfer material. An information holding mark having information for detecting at least the individual identification of the photoconductor and the integrated rotation speed of the photoconductor formed in the non-image forming area of the photoconductor,
Mark detection means for detecting the information holding mark disposed at a position facing the information holding mark of the photoconductor,
Wherein the mark detecting means detects information of the information holding mark when the information holding mark moving with the rotation of the photoconductor passes above the mark detecting means. .

Further, the photoreceptor is constituted by forming a photosensitive layer composed of a plurality of layers on a substrate, and the information holding mark is formed in a layer below an outermost layer of the plurality of layers. It is characterized by being.

The image forming apparatus further includes a cleaning unit that abuts on the surface of the photoreceptor to remove toner remaining on the surface of the photoreceptor after transfer, and the information holding mark is configured to contact the cleaning unit with the photoreceptor. It is characterized in that it is formed in the contact area.

Further, the information holding mark is a bar code.

Further, at least one of a photosensitive member, a charging means for charging the photosensitive member, and a developing means for forming a toner image on the photosensitive member is integrally formed as a cartridge. An information holding mark having information for detecting at least the individual identification of the photoconductor and the integrated rotation number of the photoconductor formed in the non-image forming area of the photoconductor; Mark detection means for detecting the information holding mark disposed at a position facing the information holding mark of the photoconductor, wherein the mark detection means is configured such that the information holding mark that moves with the rotation of the photoconductor is When passing above the mark detecting means, the information of the information holding mark is detected.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the illustrated embodiments.

Embodiment 1 FIG. 1 is a schematic configuration diagram showing an image forming apparatus (in this embodiment, an electrophotographic laser beam printer) provided with a photosensitive drum according to Embodiment 1 of the present invention. FIG. 2 is an external perspective view thereof.

The image forming apparatus (laser beam printer) A forms an image by transferring a toner image formed on a photosensitive drum 7 by an electrophotographic image forming process to a transfer material (paper, OHP sheet, etc.) 2. .

More specifically, charging roller 8 as charging means
The rotating photosensitive drum 7 is charged, and then the photosensitive drum 7 is irradiated with a laser beam corresponding to the image information input from the exposure device 1 to irradiate the photosensitive drum 7 with an electrostatic latent image corresponding to the image information. To form The exposure device 1 reflects a laser beam emitted from a laser diode 1a according to image information by a polygon mirror 1b rotating at a high speed, and scans and exposes the surface of the photosensitive drum 7 via a lens 1c and a reflection mirror 1d.

Then, the electrostatic latent image is developed with the toner of the developing device 9 to form a toner image. Developing device 9
As shown in FIG. 3, the toner in the toner container 17 is sent to the developing sleeve 9a by the rotation of the toner feeding member 9b. Then, the developing sleeve 9a containing a fixed magnet (not shown) is rotated, and the toner layer provided with the triboelectric charge by the developing blade 9c is removed from the developing sleeve 9a.
a, and supplies the toner to the developing area of the photosensitive drum 7. Then, the toner image is transferred to the electrostatic latent image on the photosensitive drum 7 to form a toner image to be visualized.

Then, in synchronization with the formation of the toner image, the transfer material 2 such as paper of a predetermined size set in a plurality of paper feed cassettes 3a is picked up by a pickup roller 3b, transport roller pairs 3c and 3d, registration roller pair 3e, and the like. Thus, the sheet is conveyed to a transfer nip portion between the photosensitive drum 7 and a transfer roller 4 as a transfer unit.

Then, the toner image formed on the photosensitive drum 7 is transferred onto the transfer material 2 by the transfer roller 4 to which a transfer bias is applied. Thereafter, the transfer material 2 having received the transfer of the toner image is conveyed to a fixing device 5 as fixing means by a conveyance guide 3f. The fixing device 5 includes a driving roller 5c and a fixing roller 5b having a built-in heater 5a.
The transfer material 2 onto which the toner image has been transferred is nipped and conveyed by a fixing nip between the driving roller 5c and the fixing roller 5b, and heat and pressure are applied to the passing transfer material 2 to fix the transferred toner image.

The transfer material 2 on which the toner image is fixed
Is conveyed by a pair of discharge rollers 3g, 3h, 3i and discharged to a discharge tray 6. The discharge tray 6 is provided on the upper surface of the apparatus main body 14 of the image forming apparatus A. It is also possible to operate the slidable flapper 3k and discharge the transfer material 2 on which the toner image is fixed by the discharge roller pair 3m from the side surface of the apparatus body 14.

After the toner image is transferred to the transfer material 2, the residual toner on the photosensitive drum 7 is removed by the cleaning blade 10a of the cleaning device 10,
In preparation for the next image forming operation.

In the image forming apparatus A of the present embodiment, the photosensitive drum 7, the charging roller 8, the developing device 9, and the cleaning device 10 are integrally formed as a cartridge to form a process cartridge B. 1
4 is detachably mounted.

As shown in FIG. 3, the process cartridge B includes a toner frame 11 containing toner and a developing device 9.
And a cleaning frame 13 having the photosensitive drum 7, the charging roller 8 and the cleaning device 10. The process cartridge B is detachably mounted on a cartridge mounting guide (not shown) as mounting means provided on the apparatus main body 14.

More specifically, a cartridge mounting guide (not shown) is provided in a cartridge mounting space that appears when the cover 35 shown in FIGS. I have. The mounting guide is provided with a groove-shaped guide portion (not shown) inclined in the direction of arrow X shown in FIG. 1, and a convex guide portion (not shown) provided at both left and right ends of the process cartridge B.
Guide.

The process cartridge B is inserted in the direction of the arrow X shown in FIG. 1 along the guide portion, and the cover 35 is closed.
4 is completed. Process cartridge B
Is taken out from the inside of the apparatus body 14, an operation reverse to the above-described mounting operation is performed.

In the above-described image forming apparatus A of the present embodiment, when the photosensitive drum 7 is replaced due to its durable life, the user easily removes the process cartridge B from the apparatus main body 14 as appropriate and replaces the entire process cartridge B. While there is an advantage that can be achieved, it is necessary to clearly indicate to the user when it should be replaced.

Therefore, in the present embodiment, as shown in FIG. 4, a bar code 40 is printed in a circumferential direction on a non-image forming area 7a on the surface of the photosensitive drum 7 using a laser marker or the like, and the bar code 40 is printed. During the image forming operation, reading is performed by the reflective photoelectric sensor 41 provided on the bearing 4c of the transfer roller 4 on the apparatus main body 14 side. The reflection type photoelectric sensor 41 is disposed at a position facing a bar code 40 formed in the non-image forming area 7 a of the photosensitive drum 7 on a bearing 4 c rotatably supporting a roller rotation shaft 4 a of the transfer roller 4. .

In this embodiment, the bar code 40
The cleaning blade 10a of the cleaning device 10 is not in contact with the non-image forming area 7a of the photosensitive drum 7 on which the bar code 40 is formed, and the bar code 40 is not scraped by the cleaning blade 10a.

The bar code 40 includes unique data for identifying the photosensitive drum 7, such as a product symbol, a serial number, and a drum serial number, and a front end and a rear end for detecting the total number of rotations of the photosensitive drum 7. Start and stop bits.

As shown in FIGS. 4 and 5, the reflection type photoelectric sensor 41 includes a light emitting portion 41a using an LED element and a Cds.
A light receiving unit 41b using a cell, and reflects light emitted from the light emitting unit 41a with the barcode 40;
The reflected light is received by the light receiving section 41b, and the data of the bar code 40 is read. Therefore, each time the photosensitive drum 7 rotates, the reflection type photoelectric sensor 41 reads the data of the bar code 40, thereby detecting the individual identification information of the photosensitive drum 7 and the information on the total number of rotations of the photosensitive drum 7, and detecting these. The information is input to a control device (not shown) provided on the device body 14 side.

The transfer roller 4 is rotated by a driving means (not shown) connected thereto by a roller gear 4b provided on a roller rotating shaft 4a meshing with a drum gear 7b of the photosensitive drum 7 during transfer. Is driven by the drive rotation of the motor. Further, the transfer roller 4
Is brought into contact with the photosensitive drum 7 with a predetermined pressure by the pressure springs 42a and 42b during transfer.

The reflection type photoelectric sensor 41 is connected to GND.
(Ground), Vcc, and Vout. The left and right guides 4d and 4e of the bearing 4c serve as contact points for GND and Vcc, respectively.
Is used as an output contact to omit wiring.

Then, the image forming apparatus A of the present embodiment
The information of the bar code 40 (the individual identification information of the photosensitive drum 7 and the accumulated rotation number information of the photosensitive drum 7) is obtained by the light receiving portion 41b of the reflection type photoelectric sensor 41 every time the photosensitive drum 7 rotated and driven during image formation rotates. ) Is read, and the read information is input to a control device (not shown) provided on the apparatus main body 14 side, and holds the individual identification of the photosensitive drum 7 and the integrated rotation number of the photosensitive drum 7.

Then, the control device obtains the photosensitive drum 7 from data stored in a memory (not shown) in advance.
Is read, and the life rotation speed is compared with the total rotation speed of the photosensitive drum 7 input from the reflection type photoelectric sensor 41. If the total rotation speed of the photosensitive drum 7 exceeds the life rotation speed, for example, The display unit (not shown) indicates "the photosensitive drum has reached its end of life" to notify the user.

Even when the process cartridge B is exchanged due to the endurance life of the photosensitive drum 7 and a process cartridge having a new photosensitive drum is mounted on the apparatus main body 14, the information of the bar code provided on the photosensitive drum is similarly read. By reading with the reflection type photoelectric sensor 41, it is possible to detect the individual identification of the photosensitive drum of the newly replaced process cartridge and to detect the integrated rotation speed.

As described above, in this embodiment, the non-image forming area 7 of the photosensitive drum 7 is
By reading the information of the barcode 40 formed in the area a, the individual identification of the photosensitive drum 7 for each individual process cartridge B and the integrated rotation number of the photosensitive drum 7 can be detected stably.

Further, since one reflective photoelectric sensor 41 is provided on the bearing 4c of the transfer roller 4, the installation space for the reflective photoelectric sensor 41 can be reduced, and the cost can be reduced.

<Second Embodiment> In the first embodiment, the bar code 4 formed in the non-image forming area 7a of the photosensitive drum 7
0 is transferred to the bearing 4 of the transfer roller 4 on the apparatus body 14 side.
In the present embodiment, the reflection type photoelectric sensor 41 is provided on the process cartridge B side.
4 is attached to a bearing portion (not shown) rotatably supporting a roller rotating shaft (not shown), and reads information of a bar code 40 formed in a non-image forming area 7a of the photosensitive drum 7 as shown in FIG. The configuration was adopted.

The charging roller 8 is rotated by driving a connected driving means (not shown) by meshing a roller gear (not shown) provided on a roller rotating shaft with a drum gear (not shown) of the photosensitive drum 7. The photosensitive drum 7 rotates following the driving rotation. Other configurations, image forming operations, and the like are the same as those in the first embodiment, and a description thereof will be omitted in the present embodiment.

The reflection type photoelectric sensor 41 includes GND (ground), Vcc, Vcc as in the first embodiment shown in FIG.
As a three-terminal configuration of out, the left and right guides (not shown) of the bearing (not shown) of the charging roller 8 are connected to GND, Vc
The wiring was omitted by setting a pressure spring (not shown) for urging the charging roller 8 to the photosensitive drum 7 as an output contact. The three signal lines are connected to the process cartridge B.
It is electrically connected to a control device (not shown) on the device body 14 side via a connector (not shown) between the device and the device body 14.

Also, in the present embodiment, similarly to the first embodiment, a control device (not shown) on the device body 14 side.
Reads the life rotation number of the photosensitive drum 7 from data stored in advance in a memory (not shown), detects the life rotation number and information of the barcode 40 from the reflection type photoelectric sensor 41, and inputs the photosensitive rotation. If the accumulated number of revolutions of the photosensitive drum 7 exceeds the life number of revolutions by comparing the accumulated number of revolutions of the drum 7, the user is notified by displaying, for example, “the photosensitive drum has reached the end of life” on a display unit (not shown).

As described above, also in the present embodiment, the information of the bar code 40 formed in the non-image forming area 7a of the photosensitive drum 7 is read by one reflection-type photoelectric sensor 41, so that the photosensitive element of each process cartridge B is exposed. The individual identification of the drum 7 and the integrated rotation speed of the photosensitive drum 7 can be detected stably.

Further, since one reflective photoelectric sensor 41 is provided on the bearing portion of the charging roller 8, the space for installing the reflective photoelectric sensor 41 can be reduced, and the cost can be reduced.

<Embodiment 3> In the present embodiment, FIG.
As shown in (1), a bar code 40 was formed on the end of the photosensitive drum 7 located in the cleaning area of the cleaning blade 10a as a cleaning means for cleaning the toner (transfer residual toner) attached to the surface of the photosensitive drum 7. The bar code 40 includes a product symbol, a serial number,
It has unique data for identifying the photosensitive drum 7, such as a drum manufacturing number, and start and stop bits for detecting the front end and the rear end for detecting the integrated rotation speed of the photosensitive drum 7.

As shown in FIG. 8, the bar code 40 is formed on the surface of the layer formed below the outermost layer of the photosensitive drum 7 along the circumferential direction. Photosensitive drum 7 of the present embodiment
As shown in FIG. 8, for example, a charge generation layer 7d and a charge transport layer 7e are formed on a drum base 7c formed of an aluminum cylinder or the like, and the bar code 40 is formed of an outermost layer (this embodiment). Is formed on the surface of the charge generation layer 7d under the charge transport layer 7e).

The information of the bar code 40 is detected by the reflection type photoelectric sensor provided on the bearing of the transfer roller or the charging roller as in the first or second embodiment. Other configurations, image forming operations, and the like are the same as those in the first or second embodiment, and a description thereof will be omitted in the present embodiment.

As described above, in this embodiment, in addition to the effects obtained in the first and second embodiments, the toner adhering to the surface of the charge transport layer 7 e on the bar code 40 of the photosensitive drum 7 becomes an obstacle. Can prevent detection errors, etc.
Since the barcode 40 is provided in a layer (charge generation layer 7d) below the outermost layer (charge transport layer 7e) of the photosensitive drum 7, the barcode 4 is provided by the cleaning blade 10a.
0 itself is not scraped off, and the function can be sufficiently performed until the life of the photosensitive drum 7.

[0050]

As described above, according to the present invention, at least an information holding mark formed on the non-image forming area of the photoreceptor for identifying the individual photoreceptor and detecting the integrated rotation number of the photoreceptor, Mark detection means for detecting an information holding mark arranged at a position facing the information holding mark of the body, and, when the information holding mark moving with the rotation of the photoconductor passes above the mark detection means, By detecting the information of the information holding mark by the mark detecting means, the individual identification of the photoreceptor and the detection of the accumulated number of rotations of the photoreceptor can be stably performed by a single mark detecting means with a cheap configuration.

[Brief description of the drawings]

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

FIG. 2 is a schematic perspective view showing the image forming apparatus according to Embodiment 1 of the present invention.

FIG. 3 is a schematic sectional view showing a process cartridge of the image forming apparatus according to Embodiment 1 of the present invention.

FIG. 4 is a schematic diagram showing a photosensitive drum and a transfer roller of the image forming apparatus according to the first embodiment of the present invention.

FIG. 5 is a diagram illustrating a configuration of a reflective photoelectric sensor in the image forming apparatus according to the first embodiment of the present invention.

FIG. 6 is a schematic sectional view showing a process cartridge of the image forming apparatus according to Embodiment 2 of the present invention.

FIG. 7 is a schematic diagram showing a photosensitive drum and a transfer roller of an image forming apparatus according to Embodiment 3 of the present invention.

FIG. 8 is a schematic sectional view showing a photosensitive drum of the image forming apparatus according to Embodiment 3 of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 Exposure device 2 Transfer material 4 Transfer roller 5 Fixing device 6 Discharge tray 7 Photosensitive drum (photoconductor) 8 Charging roller (charging means) 9 Developing device (developing device) 10 Cleaning device 14 Device body 40 Barcode (barcode) 41 Reflection type photoelectric sensor (mark detection means) 41a Light emitting unit 41b Light receiving unit A Image forming apparatus

Claims (8)

[Claims] 1. An image forming apparatus for forming an image by transferring a toner image formed on a photoreceptor detachable to an apparatus main body onto a transfer material, wherein at least the photosensitive formed on a non-image forming area of the photoreceptor An information holding mark having information for identifying an individual body and detecting an integrated rotation number of the photoconductor; and a mark detecting means for detecting the information holding mark disposed at a position of the photoconductor opposite to the information holding mark. When,
Wherein the mark detecting means detects the information of the information holding mark when the information holding mark moving with the rotation of the photoconductor passes above the mark detecting means. Image forming apparatus. 2. The image forming apparatus according to claim 1, wherein the photoconductor is formed by forming a photosensitive layer including a plurality of layers on a substrate, and the information holding mark is formed in a layer below an outermost layer among the plurality of layers. The image forming apparatus according to claim 1, wherein: 3. A cleaning means for contacting the surface of the photoreceptor to remove toner remaining on the surface of the photoreceptor after transfer, wherein the information holding mark is provided in contact with the photoreceptor by the cleaning means. The image forming apparatus according to claim 2, wherein the image forming apparatus is formed in a contact area. 4. The image forming apparatus according to claim 1, wherein the information holding mark is a bar code. 5. A photoreceptor, at least one of a charging unit for charging the photoreceptor and a developing unit for forming a toner image on the photoreceptor is integrally formed as a cartridge. An information holding mark having information for identifying at least the individual of the photoconductor and detecting an integrated rotation number of the photoconductor, wherein the information cartridge is formed in a non-image forming area of the photoconductor. Mark detection means for detecting the information holding mark arranged at a position facing the information holding mark of the photoconductor,
Wherein the mark detecting means detects the information of the information holding mark when the information holding mark moving with the rotation of the photoconductor passes above the mark detecting means. Process cartridge. 6. The photoreceptor is formed by forming a photosensitive layer composed of a plurality of layers on a substrate, and the information holding mark is formed in a layer below an outermost layer of the plurality of layers. The process cartridge according to claim 5, wherein: 7. A cleaning means for contacting the surface of the photoreceptor and removing toner remaining on the surface of the photoreceptor after transfer, wherein the information holding mark is provided in contact with the photoreceptor by the cleaning means. The process cartridge according to claim 6, wherein the process cartridge is formed in the contact area. 8. The process cartridge according to claim 5, wherein the information holding mark is a bar code.