Title: Process cartridge having storage device which communicates with image forming apparatus
Abstract: A process cartridge detachable mountable to a main assembly of an electrophotographic image forming apparatus includes an electrophotographic photosensitive drum; a developing roller for developing an electrostatic latent image formed on the photosensitive drum with developer; a transferring roller for causing transfer of the developer image from the photosensitive drum to a recording material; a cleaner, contacted to the photosensitive drum, for removing a developer remaining on the photosensitive drum; a developer accommodating portion for accommodating developer removed from the photosensitive drum by the cleaner; and a memory including a storing portion for storing predetermined information and a communicator for effecting wireless communication of the predetermined information stored in the storing portion with a main assembly side communicator provided in the main assembly of the electrophotographic image forming apparatus. The storing portion is disposed inside the developer accommodating portion and the storing portion is disposed on the same side of the process cartridge as the photosensitive drum with respect to tangent lines passing a contact point between the photosensitive drum and the developing roller or transfer roller.
Patent Number: 6,859,626 Issued on 02/22/2005 to Kimizuka, et al.
| Inventors:
|
Kimizuka; Eiichiro (Shizuoka-ken, JP);
Kanoto; Masanobu (Shizuoka-ken, JP);
Sakurai; Kazushige (Shizuoka-ken, JP)
|
| Assignee:
|
Canon Kabushiki Kaisha (Tokyo, JP)
|
| Appl. No.:
|
216220 |
| Filed:
|
August 12, 2002 |
Foreign Application Priority Data
| Sep 29, 1999[JP] | 11-276206 |
| Current U.S. Class: |
399/12; 399/25 |
| Intern'l Class: |
G03G 015//00 |
| Field of Search: |
399/9,12,24,25,31,111
|
References Cited [Referenced By]
U.S. Patent Documents
| 5343276 | Aug., 1994 | Yamashita et al. | 399/8.
|
| 5937239 | Aug., 1999 | Watanabe et al. | 399/111.
|
| 6163658 | Dec., 2000 | Suzuki | 399/12.
|
| 6212338 | Apr., 2001 | Hagihara et al. | 399/12.
|
| 6438327 | Aug., 2002 | Kimizuka et al. | 399/12.
|
| 6608975 | Aug., 2003 | Sakurai et al. | 399/25.
|
| Foreign Patent Documents |
| 11-305632 | Nov., 1999 | JP.
| |
| 11-348375 | Dec., 1999 | JP.
| |
| 2001-194966 | Jul., 2001 | JP.
| |
Primary Examiner: Beatty; Robert
Attorney, Agent or Firm: Fitzpatrick, Cella, Harper & Scinto
Parent Case Text
This application is a divisional of U.S. patent application Ser. No.
09/671,649, filed Sep. 28, 2000, now U.S. Pat. No. 6,438,327, issued Aug.
20, 2002.
Claims
What is claimed is:
1. A process cartridge detachably mountable to a main assembly of an
electrophotographic image forming apparatus having a transferring roller
and main assembly communication means, said process cartridge comprising:
an electrophotographic photosensitive drum;
cleaning means, contacting said electrophotographic photosensitive drum,
for removing developer remaining on said electrophotographic
photosensitive drum;
a developer accommodating portion configured to accommodate the developer
removed from said electrophotographic photosensitive drum by said cleaning
means;
a developing roller configured and positioned to develop an electrostatic
latent image formed on said electrophotographic photosensitive drum with
the developer; and
storing means, including an information storing portion configured to store
predetermined information and cartridge communicating means for effecting
wireless communication of the predetermined information stored in said
information storing portion with the main assembly communication means,
wherein said storing means is disposed inside said developer accommodating
portion, and said storing means is disposed at a leading side with respect
to a direction in which in said process cartridge is mounted to the main
assembly of the apparatus;
wherein said electrophotographic photosensitive drum contacts along the
length thereof the transferring roller for receiving a bias voltage to
transfer a developed image provided by said developing roller onto a
recording material; and
wherein said storing means is disposed at the same side of said process
cartridge as said electrophotographic photosensitive drum with respect to
a tangent line passing through a contact point between said
electrophotographic photosensitive drum and the transferring roller
extending in a direction crossing the longitudinal direction of said
electrophotographic photosensitive drum.
2. A process cartridge detachably mountable to a main assembly of an
electrophotographic image forming apparatus having main assembly
communication means, comprising:
an electrophotographic photosensitive drum;
cleaning means, contacting said electrophotographic photosensitive drum,
for removing developer remaining on said electrophotographic
photosensitive drum;
a developer accommodating portion configured to accommodate the developer
removed from said electrophotographic photosensitive drum by said cleaning
means;
a developing roller configured and positioned to receive a bias voltage and
to contact said electrophotographic photosensitive drum along the length
of said electrophotographic photosensitive drum to develop an
electrostatic latent image formed on said electrophotographic
photosensitive drum with the developer; and
storing means including an information storing portion configured to store
predetermined information and cartridge communicating means for effecting
wireless communication of the predetermined information stored in said
information storing portion with the main assembly communication means,
wherein said storing means is disposed inside said developer accommodating
portion, and said storing means is disposed at a leading side with respect
to a direction in which in said process cartridge is mounted to the main
assembly of the apparatus;
wherein said storing means is disposed at the same side of said process
cartridge as said electrophotographic photosensitive drum with respect to
a tangent line passing through a contact point between said
electrophotographic photosensitive drum and said developing roller and
extending in a direction crossing the longitudinal direction of said
electrophotographic photosensitive drum.
3. An electrophotographic image forming apparatus for forming an image on a
recording material, to which a process cartridge is detachably mountable,
said apparatus comprising:
(a) a transferring roller configured and positioned to cause the transfer
of a developed image from an electrophotographic photosensitive drum of
the process cartridge to the recording material;
(b) main assembly side communicating means provided in a main assembly of
said image forming apparatus for wirelessly communicating with cartridge
communicating means of the process cartridge;
(c) mounting means for detachably mounting the process cartridge, the
process cartridge including:
the electrophotographic photosensitive drum;
cleaning means, contacting the electrophotographic photosensitive drum, for
removing developer remaining on the electrophotographic photosensitive
drum;
a developer accommodating portion configured to accommodate the developer
removed from the electrophotographic photosensitive drum by the cleaning
means;
a developing roller configured and positioned to develop an electrostatic
latent image formed on the electrophotographic photosensitive drum with
the developer; and
storing means including an information storing portion configured to store
predetermined information and the cartridge communicating means for
wireless communication of the predetermined information stored in the
information storing portion with said main assembly side communicating
means;
wherein the storing means is disposed inside the developer accommodating
portion, and the storing means is disposed at a leading side with respect
to a direction in which in the process cartridge is mounted to the main
assembly of said image forming apparatus;
wherein the electrophotographic photosensitive drum contacts along the
length thereof said transferring roller for receiving a bias voltage to
transfer the developed image provided by the developing roller onto the
recording material; and
wherein the storing means is disposed at the same side of the process
cartridge as the electrophotographic photosensitive drum with respect to a
tangent line passing through a contact point between the
electrophotographic photosensitive drum and said transferring roller and
extending in a direction crossing the longitudinal direction of the
electrophotographic photosensitive drum; and
(d) feeding means for feeding the recording material.
4. An electrophotographic image forming apparatus for forming an image on a
recording material, to which a process cartridge is detachably mountable,
said apparatus comprising:
(a) main assembly communicating means provided in a main assembly of said
image forming apparatus for wirelessly communicating with cartridge
communicating means of the process cartridge;
(b) mounting means for detachably mounting the process cartridge, the
process cartridge including:
an electrophotographic photosensitive drum;
cleaning means, contacting the electrophotographic photosensitive drum, for
removing developer remaining on the electrophotographic photosensitive
drum;
a developer accommodating portion configured to accommodate the developer
removed from the electrophotographic photosensitive drum by the cleaning
means;
a developing roller configured and positioned to receive a bias voltage and
contacting the electrophotographic photosensitive drum along the length of
the electrophotographic photosensitive drum to develop an electrostatic
latent image formed on the electrophotographic photosensitive drum with
the developer; and
storing means including an information storing portion configured to store
predetermined information and the cartridge communicating means for
wireless communication of the predetermined information stored in the
information storing portion with said main assembly communicating means,
wherein the storing means is disposed inside the developer accommodating
portion, and the storing means is disposed at a leading side with respect
to a direction in which in the process cartridge is mounted to the main
assembly of said image forming apparatus; and
wherein said storing means is disposed at the same side of the process
cartridge as the electrophotographic photosensitive drum with respect to a
tangent line passing through a contact point between the
electrophotographic photosensitive drum and the developing roller and
extending in a direction crossing the longitudinal direction of the
electrophotographic photosensitive drum; and
(c) feeding means for feeding the recording material.
Description
FIELD OF THE INVENTION AND RELATED ART
The present invention relates to a process cartridge and an
electrophotographic image forming apparatus. In this specification, an
electrophotographic image forming apparatus means such an apparatus that
records images on recording media using an electrophotographic image
formation system. The examples of electrophotographic image forming
apparatuses include electrophotographic copying machines,
electrophotographic printers (laser printers, LED printers, and the like),
facsimile apparatuses, word processors, and the like.
A process cartridge is: a cartridge in which a charging means, a developing
means or a cleaning means, and an electrophotographic photosensitive
member, are integrally placed, and which is enabled to be removably
installed in the main assembly of an image forming apparatus; a cartridge
in which at least one among a charging means, a developing means, and a
cleaning means, and an electrophotographic photosensitive member, are
integrally placed, and which is enabled to be removably installed in the
main assembly of an image forming apparatus; or a cartridge in which at
least a developing means and an electrophotographic photosensitive member
are integrally placed, and which is enabled to be removably installed in
the main assembly of an image forming apparatus.
In the past, an electrophotographic image forming apparatus which employs
an electrophotographic image forming process has been employing a process
cartridge system, according to which an electrophotographic photosensitive
member, and a single or plural processing means which act on the
electrophotographic photosensitive member, are integrally placed in a
cartridge removably installable in the main assembly of an image forming
apparatus. This process cartridge system makes it possible for a user to
maintain the apparatus without relying on maintenance personnel,
drastically improving operational efficiency. Thus, the process cartridge
system has been widely used in the field of image forming apparatuses.
A process cartridge is provided with an information storing means in which
the history or specification values of the process cartridge are
registered. The information storing means is enabled to communicate with
the main assembly of an electrophotographic image forming apparatus so
that the maintenance of the electrophotographic image forming apparatus
main assembly and the process cartridge can be simplified or image quality
can be improved. Some process cartridges are provided with a connector or
the like which connects the electrophotographic image forming apparatus
main assembly to the information storing means of the process cartridge.
In order to eliminate the need for a mechanical connector which tends to
increase the cartridge size, it has been considered to employ a noncontact
communication system.
However, in the case of a process cartridge employing a wireless
communication system, the aforementioned information storing means is
affected by the electrical noises generated by the processing members, for
example, a charge roller, a development sleeve, and a transfer roller of
the apparatus main assembly, to which bias is applied from the
electrophotographic image forming apparatus. Therefore, there is a chance
that the contents of the information storing means will be destroyed or
written over with erroneous information.
The present information is one of the results of the further development of
the above described conventional technologies.
SUMMARY OF THE INVENTION
The primary object of the present invention is to provide a process
cartridge enabled to wirelessly communicate with the main assembly of an
electrophotographic image forming apparatus, and an electrophotographic
image forming apparatus in which such a process cartridge is removably
installable.
Another object of the present invention is to provide a process cartridge
capable of preventing the contents of the information storing means, which
communicates with the main assembly of an electrophotographic image
forming apparatus, from being destroyed or written over with erroneous
information, and an electrophotographic image forming apparatus in which
such a process cartridge is removably installable.
Another object of the present invention is to provide a process cartridge
in which an electrophotographic photosensitive drum is supported by a
supporting means, and the information storing means is placed in the dead
angle created by the electrophotographic photosensitive drum supporting
means, as seen from any point on the linear interface between the charging
means and the electrophotographic photosensitive means toward the
photosensitive drum in a direction perpendicular to the longitudinal
direction of the photosensitive drum, and an electrophotographic image
forming apparatus in which such a process cartridge is removably
installable.
Another object of the present invention is to provide a process cartridge
in which the information storing means is placed on the
electrophotographic photosensitive drum side with respect to a plane,
which is tangent to the peripheral surface of the electrophotographic
photosensitive drum at the linear interface between the
electrophotographic photosensitive drum and charging means, and is
perpendicular to the longitudinal direction of the electrophotographic
photosensitive drum, and also to provide an electrophotographic image
forming apparatus in which such a process cartridge is removably
installable.
Another object of the present invention is to provide a process cartridge
in which an information storing means is placed on the electrophotographic
photosensitive drum side, with respect to a plane which is tangent to the
peripheral surface of the electrophotographic photosensitive drum at the
linear interface between the transferring means and electrophotographic
photosensitive drum, and is perpendicular to the longitudinal direction of
the electrophotographic photosensitive drum, and also to provide an
electrophotographic image forming apparatus in which such a process
cartridge is removably installable.
Another object of the present invention is to provide a process cartridge
in which the information storing means is placed on the
electrophotographic photosensitive drum side, with respect to the plane
which is tangent to the peripheral surface of the electrophotographic
photosensitive drum at the linear interface between the
electrophotographic photosensitive drum and developing means, and is
perpendicular to the longitudinal direction of the electrophotographic
photosensitive drum, and also to provide an electrophotographic image
forming apparatus in which such a process cartridge is removably
installable.
Another object of the present invention is to provide a process cartridge
in which the information storing means is placed outside a theoretical
cylinder, the center line of which coincides with the axial line of the
electrophotographic photosensitive drum, and which envelops the charging
means, developing means, and transferring means, and also to provide an
electrophotographic image forming apparatus in which such a process
cartridge is removably installable.
These and other objects, features, and advantages of the present invention
will become more apparent upon consideration of the following description
of the preferred embodiments of the present invention, taken in
conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a sectional view of an electrophotographic image forming
apparatus in accordance with the present invention.
FIG. 2 is a sectional view of the process cartridge in the first embodiment
of the present invention.
FIG. 3 is a sectional view of the process cartridge in the second
embodiment of the present invention.
FIG. 4 is a sectional view of the process cartridge in the third embodiment
of the present invention.
FIG. 5 is a sectional view of the process cartridge in the fourth
embodiment of the present invention.
FIG. 6 is a sectional view of the process cartridge in the fifth embodiment
of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Hereinafter, the preferred embodiments of the present invention will be
described with reference to the appended drawings.
Embodiment 1
Referring to FIGS. 1 and 2, a process cartridge will be described along
with an electrophotographic image forming apparatus in which a process
cartridge is removably installable. FIG. 1 is a sectional view of an
electrophotographic image forming apparatus (laser beam printer) in which
a process cartridge has been installed, and depicts the general structure
of the apparatus. FIG. 2 is a sectional view of a process cartridge, and
depicts the general structure thereof.
As for the order of descriptions, first, the general structure of an
electrophotographic image forming apparatus in which a process cartridge
has been installed will be described, and then, the structure of a process
cartridge will be described.
(General Structure)
Referring to FIG. 1, this electrophotographic image forming apparatus A
(laser beam printer) is such an apparatus that forms an image on recording
media (for example, recording paper, OHP sheet, fabric, and the like) with
the use of an electrophotographic image formation process. In operation,
it forms a toner image (developer image) on an electrophotographic
photosensitive drum 7 (hereinafter, "photosensitive drum") in the form of
a drum. More specifically, the photosensitive drum 7 is charged by a
charging means 8, and then, the photosensitive drum 7 is exposed to a
laser beam projected onto the photosensitive drum 7 from an optical means
1 while being modulated with image formation information, to form an
electrostatic latent image in accordance with the image formation
information, on the photosensitive drum 7. The thus formed electrostatic
latent image is developed into a toner image by a developing means 9.
Meanwhile, a recording medium 2 having been placed in a cassette 3a is
conveyed by a conveying means 3 comprising a pickup roller 3b, a
combination 3c of a feed roller and retard roller, two pairs 3d and 3e of
conveying rollers, and the like, while being turned over, in synchronism
with the toner image formation. Next, the toner image formed on the
photosensitive drum 7 in the process cartridge B is transferred onto the
recording medium 2 by applying voltage (transfer bias) to a transfer
roller 4 as a transferring means with which the main assembly A1
(hereinafter, "image forming apparatus main assembly") of an
electrophotographic image forming apparatus is provided. The transfer
roller 4 comes into contact with the photosensitive drum 7 in such a
manner that the linear interface between the two rollers becomes parallel
to the longitudinal direction (axial line direction) of the photosensitive
drum 7, as the process cartridge B is installed into the image forming
apparatus main assembly A1.
After receiving the toner image, the recording medium 2 is conveyed to a
fixing means 5 by a conveyer belt 3f. The fixing means 5 comprises a
driver roller 5a and a rotational fixing member 5b. The rotational fixing
member 5b is a cylindrical sheet, and contains a heater. It is rotatably
supported by a supporting member. The fixing means 5 applies pressure and
heat to the recording medium 2 to fix the transferred toner image to the
recording medium 2 while the recording medium 2 is passing through the
fixing means 5.
Thereafter, the recording medium 2 is conveyed through a reversing path,
and discharged into a delivery tray 6, by two pairs 3g and 3h of discharge
rollers. The aforementioned optical means 1 comprises a laser diode, a
polygon mirror, a lens, and a refection mirror, although they are not
illustrated.
(Process Cartridge Structure)
The process cartridge B is such a cartridge that is provided with an
electrophotographic photosensitive member, and at least one processing
means. As for processing means, there are a charging means for charging an
electrophotographic photosensitive member, a developing means for
developing an electrostatic latent image formed on an electrophotographic
photosensitive member, and a cleaning means for cleaning the toner
particles remaining on the peripheral surface of an electrophotographic
photosensitive member, for example. Referring to FIG. 2, in the process
cartridge B in this embodiment, the photosensitive drum 7 with a
photosensitive layer is rotated, and while it is rotated, its peripheral
surface is uniformly charged by the voltage (charge bias) applied to a
primary charge roller 8 (hereinafter, "charge roller") as a charging
means. Then, a laser beam modulated with the image formation information
from the optical means 1 is projected upon the photosensitive drum 7
through an exposure opening (unillustrated) to form an electrostatic
latent image. This electrostatic latent image is developed by the
developing means 9 which uses toner. More specifically, the charge roller
8 is placed in contact with the photosensitive drum 7 in such a manner
that the longitudinal axes of the two components become parallel to each
other. As charge bias is applied to the charge roller 8 from the image
forming apparatus main assembly A1, the photosensitive drum 7 is charged.
The charge roller 8 rotates by following the rotation of the
photosensitive drum 7. The developing means 9 supplies the development
region of the photosensitive drum 7 with toner to develop the
electrostatic image formed on the photosensitive drum 7.
The developing means 9 sends the toner within the toner container 11 toward
a development sleeve 9a by the rotation of a toner conveying member 9b.
Further, it rotates the development sleeve 9a, in which a stationary
magnet is contained, and forms a layer of toner on the peripheral surface
of the development sleeve 9a, while triboelectrically charging the toner,
by a development blade 9d. The triboelectrically charged toner on the
peripheral surface of the development sleeve 9a is supplied to the
development region of the photosensitive drum 7. The development sleeve 9a
is provided with a pair of spacer rings 9i as a gap maintaining means,
which are fitted one for one around the longitudinal (axial direction) end
portions of the development sleeve 9a, and remain in contact with the
peripheral surface of the photosensitive drum 7 at the longitudinal ends
of the photosensitive drum 7, maintaining a predetermined distance between
the peripheral surface of the development sleeve 9a and photosensitive
drum 7. In operation, development bias is applied from the image forming
apparatus main assembly A1 to the development sleeve 9a so that the toner
on the development sleeve 9a is transferred onto the photosensitive drum 7
in accordance with the pattern of the aforementioned electrostatic latent
image to form a toner image, or a visual image. The development blade 9d
is a blade for regulating the amount of the toner on the peripheral
surface of the development sleeve 9a, as well as for charging the toner.
In the areas adjacent to the development sleeve 9a, a toner stirring
member 9e for recirculating the toner within the development chamber is
rotatably mounted.
After the toner image formed on the photosensitive drum 7 is transferred
onto the recording medium 2 by applying voltage (transfer bias) opposite
in polarity to the toner image, to the transfer roller 4, the toner
particles remaining on the photosensitive drum 7 are removed by the
cleaning means 10. More specifically, the cleaning means 10 scrapes the
toner particles remaining on the photosensitive drum 7, down into the
waste toner bin 10c by the rubber cleaning blade 10a attached to the
longitudinal tip portion of a cleaning blade holding member 10b. The
cleaning blade holding member 10b is formed of a piece of electrically
conductive plate, and holds the rubber cleaning blade 10a in such a manner
that the rubber cleaning blade 10a extends in the longitudinal direction
of the photosensitive drum 7.
The process cartridge B in this embodiment comprises: a toner container 11
which stores toner, and has a toner conveying member 9b; a developing
means container 12 which holds the developing means such as the
development sleeve 9a, development blade 9d, and the like; a cleaning
means frame 13 to which the photosensitive drum 7, the cleaning means 10
such as the rubber cleaning blade 10a, cleaning blade holding member 10b,
and the like, and the charge roller 8, are attached. In assembling the
process cartridge B, first, the toner container 11 and developing means
container 12 are joined together, forming a developing means frame 15, and
then, the developing means frame 15 is integrated with the cleaning means
frame, completing the process cartridge B, which is removably installable
into the cartridge installing means of the image forming apparatus main
assembly A1 by an operator.
Referring again to FIG. 1, the cartridge installing means comprises a lid
16 which can be rotationally opened about an axis 16a, and cartridge
guiding members (unillustrated) located on the internal surfaces of the
left and right side walls of the cartridge installation space, which can
be exposed by opening the lid 16. During the installation or removal of
the process cartridge B, the guiding portions of the process cartridge B,
which comprise bosses and ribs, engage with the cartridge installation
guiding means on the image forming apparatus main assembly A1 side and are
guided thereby, so that the process cartridge B is installed into or
removed from the image forming apparatus main assembly in the direction of
an arrow mark A.
(Description of Electrical Contact Points)
The process cartridge B is provided with a charge bias contact point
(unillustrated) for applying charge bias to the charge roller 8 from the
image forming apparatus main assembly A1, a development bias contact point
(unillustrated) for applying development bias to the development sleeve
9a, and a ground contact point (unillustrated) for grounding the
photosensitive drum 7, which are placed at predetermined locations. The
image forming apparatus main assembly A1 is provided with a charge bias
contact point member (unillustrated), a development bias contact point
member (unillustrated), and a ground contact point member (unillustrated),
which make electrical contact with the charge bias contact point,
development bias contact point, and ground contact point, correspondingly,
as the process cartridge B is inserted to a predetermined point in the
aforementioned cartridge installation space. Thus, as the process
cartridge B arrives at the predetermined point in the cartridge
installation space by being guided by the installation guiding member of
the image forming apparatus main assembly A1, the charge bias contact
point makes electrical contact with the charge bias contact point member,
the development bias contact point makes electrical contact with the
development bias contact point member, and the ground contact point makes
electrical contact with the ground contact point member. As a result, it
becomes possible for the charge bias (compound bias comprising AC voltage
and DC voltage) to be applied to the charge roller 8 from an unillustrated
bias supplying source (electrical power source) of the image forming
apparatus main assembly A1 through the charge bias contact point member
and charge bias contact point, and for the development bias to be applied
to the development sleeve 9a from the above mentioned bias supplying
source through the development bias contact point member and development
bias contact point. Further, it becomes possible for the transfer bias to
be applied to the transfer roller 4 from the aforementioned bias supplying
source.
(Means for Preventing Bias Application Noise Reaching Information Storing
Means)
Referring to FIGS. 1 and 2, the process cartridge B in this embodiment is
provided with an information storing means 14 for communicating with the
image forming apparatus main assembly A1 in a noncontact manner, that is,
wirelessly. The information storing means 14 is placed within the cleaning
means frame 13. As the process cartridge B is installed into the image
forming apparatus main assembly A1, the information storing means 14 comes
to face a communication antenna 15 as the communicating means in the image
forming apparatus main assembly A1, being therefore enabled to communicate
with the image forming apparatus main assembly A1. The information storing
means 14 comprises an information storing portion 14a for storing
predetermined information, and a communicating means 14b for communicating
with the image forming apparatus main assembly A1, which are integrated.
In this embodiment, a wireless communication system based on
electromagnetic induction is employed as a noncontact communication
system. More specifically, a magnetic core integral with the information
storing portion 14a of the information storing means 14 is used as the
communicating means 14b on the process cartridge B side, and the image
forming apparatus main assembly A1 is provided with an inductor as the
communicating means on the image forming apparatus main assembly A1 side,
so that the communication between the image forming apparatus main
assembly A1 and process cartridge B can be carried out by electromagnetic
induction through the magnetic core. In operation, predetermined types of
information, for example, service history or cartridge specification
values, are registered in the information storing portion 14a of the
information storing means 14, so that the maintenance of the image forming
apparatus main assembly A1 or process cartridge B is simplified, and/or
image quality is improved through the communication between the process
cartridge B and image forming apparatus main assembly A1.
Referring to FIG. 2, the information storing means 14 is placed in a dead
region P1 (hatched region) created by the cleaning blade holding member
10b, in terms of the electromagnetic waves radiating from any point on the
linear interface P11 between the charge roller 8 and photosensitive drum 7
in the direction intersecting (approximately perpendicular) the
longitudinal direction of the photosensitive drum 7. This placement of the
information storing means 14 is effective to make the cleaning blade
holding member 10b shield the information storing means 14 from the noises
created by the bias applied to the charge roller 8, making it possible to
prevent the information storing portion 14a of the information storing
means from being affected by the above described noise; it is effective to
prevent the information stored in the information storing portion 14a from
being destroyed by the noise. In other words, since the information
storing portion 14a is shielded by the cleaning blade holding member 10b
from the effects of the noises generated by the charge bias applied to the
charge roller 8, the predetermined information stored in the information
storing member 14a of the information storing means 4 is prevented from
being destroyed or written over with erroneous information. Thus, it is
possible to prevent the effects of the noises generated by the charge bias
applied to the charge roller 8 that the information storing means 14
destroys the information stored therein, or erroneously operates.
Embodiment 2
In this embodiment, another example of a process cartridge in accordance
with the present invention will be described. In this cartridge, in order
to prevent the information storing means 14 from being affected by the
noises caused by the charge bias applied to the charge roller 8 of the
process cartridge B, the information storing means 14 is placed within the
cleaning means frame 13. The components in this cartridge similar to those
in the process cartridge B in the first embodiment are given the same
reference codes as those in the first embodiment.
FIG. 3 is a sectional view of the process cartridge in this embodiment. In
this embodiment, the information storing means 14 is placed in a region P2
(hatched region), which is on the photosensitive drum 7 side with respect
to a plane L1, which is tangent to peripheral surface of the
photosensitive drum 7 at the linear interface P22 between the charge
roller 8 and photosensitive drum 7, and intersects (approximately
perpendicular) the longitudinal direction of the photosensitive drum 7, as
shown in FIG. 3. Since the information storing means 14 is placed in the
region P2 (hatched region), which is on the photosensitive drum 7 side
with respect to a plane L1, which is tangent to peripheral surface of the
photosensitive drum 7 at the linear interface P22 between the charge
roller 8 and photosensitive drum 7, and intersects (approximately
perpendicular) the longitudinal direction of the photosensitive drum 7,
the information storing means 14 is shielded by the photosensitive drum 7
from the noises generated by the charge bias applied to the charge roller
8. More specifically, the photosensitive drum 7 is electrically connected
to the ground contact point member of the image forming apparatus main
assembly A1 through the ground contact point, and therefore, the noises
from the charge bias are led to the ground contact point member of the
image forming apparatus main assembly A1 through the ground contact point.
of the photosensitive drum 7. In other words, the noises which dissipate
from the linear interface P22 are blocked by the portion of the peripheral
surface of photosensitive drum 7 in the region P2 on the photosensitive
drum 7 side with respect to the aforementioned plane L1 tangent to the
peripheral surface of the photosensitive drum 7 at the linear interface
P22. With this arrangement, it is possible to prevent the problem that the
predetermined information stored in the information storing portion 14a of
the information storing means 14 is destroyed, or written over with
erroneous information, by the effects of the noises from the charge bias
applied to the charge roller 8. Thus, it is possible to prevent the
problem that the information storing means 14 is caused to destroy the
information stored therein, or to erroneously operate, by the noises from
the charge bias applied to the charge roller 8.
Embodiment 3
In this embodiment, another example of a process cartridge in accordance
with the present invention will be described. In this cartridge, in order
to prevent the information storing means 14 from being affected by the
noises caused by the transfer bias applied to the transfer roller 4 of the
process cartridge B, the information storing means 14 is placed within the
cleaning means frame 13. The components in this cartridge similar to those
in the process cartridge B in the first embodiment are given the same
reference codes as those in the first embodiment.
FIG. 4 is a sectional view of the process cartridge in this embodiment. In
this embodiment, the information storing means 14 is placed in a region P3
(hatched region), which is on the photosensitive drum 7 side with respect
to a plane L2, which is tangent to peripheral surface of the
photosensitive drum 7 at the linear interface P33 between the transfer
roller 4 and photosensitive drum 7, and intersects (approximately
perpendicular) the longitudinal direction of the photosensitive drum 7, as
shown in FIG. 4. Since the information storing means 14 is placed in the
region P3 (hatched region), which is on the photosensitive drum 7 side
with respect to a plane L2, which is tangent to peripheral surface of the
photosensitive drum 7 at the linear interface P33 between the transfer
roller 4 and photosensitive drum 7, and intersects (approximately
perpendicular) the longitudinal direction of the photosensitive drum 7,
the noises caused by the transfer bias applied to the transfer roller 4
are blocked by the photosensitive drum 7. More specifically, the
photosensitive drum 7 is electrically connected to the ground contact
point member of the image forming apparatus main assembly A1 through the
ground contact point, and therefore, the noises from the transfer bias are
led to the ground contact point member of the image forming apparatus main
assembly A1 through the ground contact point of the photosensitive drum 7.
In other words, the noises which dissipate from the linear interface P33
are blocked by the portion of the peripheral surface of photosensitive
drum 7 in the region P3 on the photosensitive drum 7 side with respect to
the aforementioned plane L2 tangent to the peripheral surface of the
photosensitive drum 7 at the linear interface P33. With this arrangement,
it is possible to prevent the problem that the predetermined information
stored in the information storing portion 14a of the information storing
means 14 is destroyed, or written over with erroneous information, by the
effects of the noises from the transfer bias applied to the transfer
roller 4. Thus, it is possible to prevent the problem that the information
storing means 14 is caused to destroy the information stored therein, or
to erroneously operate, by the noises from the transfer bias applied to
the transfer roller 4.
Embodiment 4
In this embodiment, another example of a process cartridge in accordance
with the present invention will be described. In this cartridge, in order
to prevent the information storing means 14 from being affected by the
noises caused by the development bias applied to the charge roller 8 of
the process cartridge B, the information storing means 14 is placed within
the cleaning means frame 13. The components in this embodiment similar to
those the first embodiment are given the same reference codes as those in
the first embodiment.
FIG. 5 is a sectional view of the process cartridge in this embodiment. In
this embodiment, the information storing means 14 is placed in a region P4
(hatched region), which is on the photosensitive drum 7 side with respect
to a plane L3, which is tangent to peripheral surface of the
photosensitive drum 7 at the linear interface P44 between the spacer ring
9i of the development sleeve 9a and the photosensitive drum 7, and
intersects (approximately perpendicular) the longitudinal direction of the
photosensitive drum 7, as shown in FIG. 5. Since the information storing
means 14 is placed in the region P4 (hatched region), which is on the
photosensitive drum 7 side with respect to the plane L3, which is tangent
to peripheral surface of the photosensitive drum 7 at the linear interface
P44 between the spacer ring 9i of the development sleeve 9a and the
photosensitive drum 7, and intersects (approximately perpendicular) the
longitudinal direction of the photosensitive drum 7, the noises caused by
the development bias applied to the development sleeve 9a are blocked by
the photosensitive drum 7. More specifically, the photosensitive drum 7 is
electrically connected to the ground contact point member of the image
forming apparatus main assembly A1 through the ground contact point, and
therefore, the noises from the development bias are led to the ground
contact point member of the image forming apparatus main assembly A1
through the ground contact point of the photosensitive drum 7. In other
words, the noises which dissipate from the linear interface P44 are
blocked by the portion of the peripheral surface of photosensitive drum 7
in the region P4 on the photosensitive drum 7 side with respect to the
aforementioned plane L3 tangent to the peripheral surface of the
photosensitive drum 7 at the linear interface P44. Therefore, it is
possible to prevent the problem that the predetermined information stored
in the information storing portion 14a of the information storing means 14
is destroyed or written over with erroneous information, by the effects of
the noises from the development bias applied to the development sleeve 9a.
Thus, it is possible to prevent the problem that the information storing
means 14 is caused to destroy the information stored therein, or to
erroneously operate, by the noises from the development bias applied to
the development sleeve 9a.
Embodiment 5
This embodiment, which will be described next, is a case in which the
information storing means 14 is placed within the cleaning means frame 13
to prevent the information storing means 14 from being subjected to the
effects of the noises generated by the charge bias applied to the charge
roller 8 of the process cartridge B, the noises generated by the
development bias applied to the development sleeve 9a of the process
cartridge B, and the noises generated by the transfer bias applied to the
transfer roller 4 of the image forming apparatus main assembly A1. The
components in this embodiment similar to those in the first embodiment are
given the same reference codes as those in the first embodiment.
FIG. 6 is a sectional view of the process cartridge in this embodiment. In
this embodiment, the information storing means 14 is in a region P5
(hatched region), that is, the region outside a theoretical cylinder P55,
the axial line of which coincides with the rotational center (axial line)
of the photosensitive drum 7, and which is in contact with the peripheral
surface of the photosensitive drum 7 and envelops all the processing
members, that is, the transfer roller 4, charge roller 8, and development
sleeve 9a, to which bias is applied from the image forming apparatus main
assembly A1. Since the information storing means 14 is placed outside the
theoretical cylinder P55, the axial line of which coincides with the
rotational center (axial line) of the photosensitive drum 7, and which is
in contact with the peripheral surface of the photosensitive drum 7 and
envelops all the processing members to which bias is applied from the
image forming apparatus main assembly A1, the noises generated by the
transfer bias applied to the transfer roller 4, the noises generated by
the charge bias applied to the charge roller 8, and the noises generated
by the development bias applied to the development sleeve 9a, are all
blocked by the photosensitive drum 7. More specifically, the
photosensitive drum 7 is electrically connected to the ground contact
point member of the image forming apparatus main assembly A1 through the
ground contact point, and therefore, the noises generated by the transfer
bias, charge bias, and development bias, at the-linear interface P22
between the photosensitive drum 7 and transfer roller 4, the linear
interface P33 between the photosensitive drum 7 and charge roller 8, and
the linear interface P44 between the photosensitive drum 7 and development
roller 9a, correspondingly, are led to the ground contact point member of
the image forming apparatus main assembly A1 through the ground contact
point of the photosensitive drum 7. In other words, the noises which
dissipate from the linear interface P22 between the photosensitive drum 7
and transfer roller 4, the linear interface P33 between the photosensitive
drum 7 and charge roller 8, and the linear interface P44 between the
photosensitive drum 7 and development roller 9a, correspondingly, are
blocked by the portion of the peripheral surface of the photosensitive
drum 7 at and in the adjacencies of the linear interfaces P22, P33, and
P44, within the theoretical cylinder P55. Therefore, it is possible to
prevent the problem that the predetermined information which the
information storing portion 14a of the information storing means 14 stores
is destroyed or written over with erroneous information by the effects of
the noises generated by the biases applied to the aforementioned
processing members. Thus, it is possible to prevent the problem that the
information storing means 14 is caused by the effects of the noises
generated by the biases applied to the processing members, to destroy the
contents of the information storing portion 14a, or to erroneously
operate.
Miscellaneous Embodiments
The process cartridges in the preceding embodiments were for forming a
monochromatic image. However, the present invention is also applicable,
with excellent results, to a process cartridge which is enabled to form a
multicolor image (for example, two tone image, three tone image, or
full-color image) with the provision of a plurality of developing means.
The selection of the electrophotographic photosensitive member does not
need to be limited to the aforementioned photosensitive drum. For example,
it may include the following. As for the photosensitive material, various
photoconductors, for example, amorphous silicon, amorphous selenium, zinc
oxide, titanium oxide, as well as organic photoconductors, may be
employed. As for the shape of the base member on which the photosensitive
material is borne, it may be in the form of a drum or a belt, for example.
In the case of a drum type photosensitive member, it is produced by
depositing or painting photoconductor on the peripheral surface of a
cylindrical base member formed of aluminum alloy or the like.
The definition of the aforementioned process cartridge, in other words, a
cartridge to which the present invention is applicable, is such a
cartridge that comprises, for example, an electrophotographic
photosensitive member, and at least one processing means. In other words,
in addition to the process cartridge referred to in the descriptions of
the preceding embodiments, there are many process cartridges of various
forms, to which the present invention is applicable; for example, a
cartridge in which an electrophotographic photosensitive member and a
charging member are integrally placed so that they can be removably
installed in the apparatus main assembly, a cartridge in which an
electrophotographic photosensitive member and a developing means are
integrally placed so that they can be removably installed in the apparatus
main assembly, a cartridge in which an electrophotographic photosensitive
member and a cleaning means are integrally placed so that they can be
removably installed in the apparatus main assembly, a process cartridge in
which an electrophotographic photosensitive member and a combination of
two or more among the aforementioned processing means are integrally
placed so that they can be removably installed in the apparatus main
assembly, and the like cartridges.
In other words, the definition of the aforementioned process cartridge is a
cartridge which is removably installable in the image forming apparatus
main assembly, and in which a charging means, a developing means or a
cleaning means, and an electrophotographic photosensitive member, are
integrally placed, a cartridge which is removably installable in the image
forming apparatus main assembly, and in which at least one among a
charging means, a developing means and a cleaning means, and an
electrophotographic photosensitive member, are integrally placed, or a
cartridge which is removably installable in the image forming apparatus
main assembly, and in which at least a developing means and an
electrophotographic photosensitive member are integrally placed. Thus, the
apparatus main assembly can be maintained by a user himself or herself.
Further, in the preceding embodiments, a laser beam printer was referred to
as an electrophotographic image forming apparatus. However, the
application of the present invention does not need to be limited to a
laser beam printer. Obviously, the present invention is also applicable to
electrophotographic image forming apparatus of other forms, for example,
electrophotographic copying machines, facsimile apparatuses, and word
processors.
As described above, a process cartridge in accordance with the present
invention can prevent the problem that the contents of the information
storing means which wirelessly communicates with the electrophotographic
image forming apparatus main assembly are destroyed or written over with
erroneous information by the effects of the electrical noises generated by
bias application.
An electrophotographic image forming apparatus in accordance with the
present invention can removably accommodate a process cartridge in
accordance with the present invention which can prevent the problem that
the contents of the information storing means which wirelessly
communicates with the electrophotographic image forming apparatus main
assembly are destroyed or written over with erroneous information by the
effects of the electrical noises generated by bias application.
While the invention has been described with reference to the structured
disclosed herein, it is not confined to the details set forth, and this
application is intended to cover such modifications or changes as may come
within the purposes of the improvements or the scope of the following
claims.
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