U.S. patent application number 14/276293 was filed with the patent office on 2016-08-18 for image forming apparatus.
This patent application is currently assigned to CANON KABUSHIKI KAISHA. The applicant listed for this patent is CANON KABUSHIKI KAISHA. Invention is credited to Yuji Mitsui, Koji Miwa, Keita Nakajima, Ryuji Tanaami.
Application Number | 20160238987 14/276293 |
Document ID | / |
Family ID | 54538437 |
Filed Date | 2016-08-18 |
United States Patent
Application |
20160238987 |
Kind Code |
A9 |
Tanaami; Ryuji ; et
al. |
August 18, 2016 |
IMAGE FORMING APPARATUS
Abstract
The present invention provides an image forming apparatus
including: a first moving member pressed and moved by an
openable/closable member when the openable/closable member is
opened, and switching a cartridge from a state where the cartridge
is positioned in an image forming position to a state where the
positioning is released; and a second moving member pressed and
moved by the openable/closable member when the openable/closable
member is opened, and moving the exposure member from an exposure
position to a retracted position, wherein when the positioning of
the cartridge is released, a reaction force applied from the first
moving member to the openable/closable member reaches a first peak,
when the exposure member is moved to the retracted position, a
reaction force applied from the second moving member to the
openable/closable member reaches a second peak, and timing of the
first peak is different from timing of the second peak.
Inventors: |
Tanaami; Ryuji;
(Yokohama-shi, JP) ; Nakajima; Keita; (Suntou-gun,
JP) ; Miwa; Koji; (Susono-shi, JP) ; Mitsui;
Yuji; (Susono-shi, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
CANON KABUSHIKI KAISHA |
Tokyo |
|
JP |
|
|
Assignee: |
CANON KABUSHIKI KAISHA
Tokyo
JP
|
Prior
Publication: |
|
Document Identifier |
Publication Date |
|
US 20150331386 A1 |
November 19, 2015 |
|
|
Family ID: |
54538437 |
Appl. No.: |
14/276293 |
Filed: |
May 13, 2014 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
13115237 |
May 25, 2011 |
8768202 |
|
|
14276293 |
|
|
|
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
G03G 2215/0668 20130101;
G03B 27/523 20130101; G03G 2215/0692 20130101; G03B 27/528
20130101; G03G 21/1633 20130101; G03G 21/1853 20130101; B41J 11/46
20130101; G03G 15/0865 20130101; G03G 21/1666 20130101; G03G 15/00
20130101; G03G 15/0868 20130101; G03G 15/04036 20130101; G03G 15/04
20130101; G03G 15/0872 20130101 |
International
Class: |
G03G 21/16 20060101
G03G021/16 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 2, 2010 |
JP |
2010-126812 |
Apr 15, 2011 |
JP |
2011-091240 |
May 23, 2011 |
JP |
2011-114806 |
Claims
1. An image forming apparatus in which a cartridge that supports a
photosensitive member is mounted to an image forming position, and
which forms a latent image on the photosensitive member by exposure
to form an image, the apparatus comprising: an exposure member that
(i) includes a light emitting element arranged in an array and (ii)
exposes the photosensitive member of the cartridge located in the
image forming position when the exposure member is in an exposure
position; an operation member that moves to a first position and a
second position with respect to a main body of the apparatus; a
first moving member that is pressed and moved by the operation
member when the operation member is moved from the first position
to the second position, and switches the cartridge from a state
where the cartridge is positioned in the image forming position to
a state where the positioning is released; and a second moving
member that is pressed and moved by the operation member when the
operation member is moved from the first position to the second
position, and moves the exposure member from the exposure position
to a retracted position where the exposure member is more retracted
from the photosensitive member than the exposure position, wherein,
while the operation member is moved from the first position to the
second position to switch the cartridge from the state where the
cartridge is positioned to the state where the positioning is
released, a first force acts from the first moving member to the
operation member in a direction in which the moving of the
operation member from the first position to the second position is
suppressed, and wherein, while the operation member is moved from
the first position to the second position to move the exposure
member from the exposure position to the retracted position, a
second force acts from the second moving member to the operation
member in a direction in which the moving of the operation member
from the first position to the second position is suppressed, and
wherein, while the operation member is moved from the first
position to the second position, timing of a peak of the first
force is different from timing of a peak of the second force.
2-12. (canceled)
13. The image forming apparatus according to claim 1, wherein, as
the operation member is moved from the first position to the second
position, the operation member presses and moves the second moving
member and then presses and moves the first moving member.
14. The image forming apparatus according to claim 1, wherein the
first moving member is pressed and moved by the operation member to
position the cartridge in the image forming position when the
operation member is moved from the second position to the first
position, wherein the second moving member is pressed and moved by
the operation member to move the exposure member from the retracted
position to the exposure position when the operation member is
moved from the second position to the first position, and wherein
timing when the operation member presses the first moving member to
position the cartridge in the image forming position is different
from timing when the operation member presses the second moving
member to move the exposure member to the exposure position.
15. The image forming apparatus according to claim 14, wherein the
first moving member and the second moving member are moved by a
toggle mechanism.
16. The image forming apparatus according to claim 1, wherein the
operation member is an openable and closable member that can be
open or closed with respect to the main body of the apparatus,
wherein the openable and closable member is closed with respect to
the main body of the apparatus when the openable and closable
member is in the first position, and wherein the openable and
closable member is more open with respect to the main body of the
apparatus when the openable and closable member is in the second
position than in the first position so that the cartridge can be
mounted to the main body of the apparatus.
17. An image forming apparatus in which a cartridge that supports a
photosensitive member is mounted to an image forming position, and
which forms a latent image on the photosensitive member by exposure
to form an image, the apparatus comprising: an exposure member that
(i) includes a plurality of light emitting elements arranged in an
array and (ii) exposes the photosensitive member of the cartridge
located in the image forming position by the plurality of light
emitting elements when the exposure member is in an exposure
position, the exposure member being movable to a retracted position
where the exposure member is more retracted from the photosensitive
member than the exposure position; an operation member that moves
to a first position and a second position with respect to a main
body of the apparatus; a first moving member that moves the
cartridge to the image forming position by moving the cartridge in
a direction different from an insertion direction of the cartridge
into the main body of the apparatus when the cartridge is mounted
to the main body of the apparatus; and a second moving member that
moves the exposure member from the retracted position to the
exposure position as the operation member is moved from the second
position to the first position.
18. The image forming apparatus according to claim 17, wherein the
operation member is an openable and closable member that can be
open or closed with respect to the main body of the apparatus,
wherein the openable and closable member is closed with respect to
the main body of the apparatus when the openable and closable
member is in the first position, and wherein the openable and
closable member is more open with respect to the main body of the
apparatus when the openable and closable member is in the second
position than in the first position so that the cartridge can be
mounted to the main body of the apparatus.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to an electrophotographic
image forming apparatus that forms an image on a recording medium
in a state where a process cartridge including an
electrophotographic photosensitive drum and a process unit that
acts on the drum is removably mounted to a main body of the
electrophotographic image forming apparatus.
[0003] An electrophotographic image forming apparatus forms an
image on a recording medium using an electrophotographic image
forming process. The electrophotographic image forming apparatus
includes, for example, an electrophotographic copier, an
electrophotographic printer (for example, a laser beam printer or
an LED printer), a facsimile apparatus, and a word processor. The
recording medium includes, for example, paper or an OHT sheet on
which an image is formed by the electrophotographic image forming
apparatus.
[0004] A process cartridge contributes to an image forming process
for forming an image on a recording medium in a state where the
cartridge is removably mounted to a main body of an
electrophotographic image forming apparatus. The main body is a
component of the electrophotographic image forming apparatus except
the cartridge. The process cartridge includes at least one of a
charging unit, a developing unit, and a cleaning unit as process
units, and an electrophotographic photosensitive drum on which an
electrostatic latent image is formed, integrated into a cartridge,
and is removably mounted to the main body. The process unit acts on
the electrophotographic photosensitive drum. Thus, the process
cartridge also includes a cartridge including a developing unit as
a process unit and an electrophotographic photosensitive drum
integrated into the cartridge, and removably mounted to the main
body. The process cartridge further includes a cartridge including
a charging unit, a developing unit or a cleaning unit as a process
unit and an electrophotographic photosensitive drum integrated into
the cartridge, and removably mounted to the main body. The process
cartridge can be mounted to and removed from the main body by a
user. This facilitates maintenance of the main body.
[0005] 2. Description of the Related Art
[0006] In an image forming apparatus disclosed in Japanese Patent
Application Laid-Open No. H05-035003, an exposure unit is pressed
against a part of an exterior component of a cartridge including a
photosensitive drum in conjunction with an opening/closing
operation of an exterior cover. This can maintain a certain
distance between the exposure unit and the cartridge.
SUMMARY OF THE INVENTION
[0007] Japanese Patent Application Laid-Open No. H05-035003 adopts
a method of pressing an exposure unit against a cartridge using a
spring, and maintaining a certain distance between an exposure unit
and a cartridge. However, timing of cartridge pressing is the same
as timing of exposure unit pressing, and thus a large force is
required for closing a cover, and reducing an opening/closing force
is desired in terms of usability.
[0008] Thus, in the present invention, timing of cartridge pressing
is shifted from timing of exposure unit pressing to reduce a force
required for pressing.
[0009] The present invention provides image forming apparatus in
which a cartridge that supports a photosensitive member is mounted
to an image forming position, and which forms a latent image on the
photosensitive member by exposure to form an image, including: an
exposure member that includes a light emitting element arranged in
an array, and exposes the photosensitive member of the cartridge
located in the image forming position in an exposure position; an
openable and closable member that can be opened or closed with
respect to a main body of the apparatus, and can mount the
cartridge to the main body of the apparatus in a state of being
opened with respect to the main body of the apparatus; a first
moving member that is pressed and moved by the openable and
closable member when the openable and closable member is opened,
and switches the cartridge from a state where the cartridge is
positioned in the image forming position to a state where the
positioning is released; and a second moving member that is pressed
and moved by the openable and closable member when the openable and
closable member is opened, and moves the exposure member from the
exposure position in an arrangement direction of the cartridge and
the exposure member and thus moves the exposure member to a
retracted position retracted from the exposure position, wherein,
while the openable and closable member is being opened, when the
first moving member switches the cartridge to the state where the
positioning is released, a reaction force applied from the first
moving member to the openable and closable member reaches a first
peak, and when the second moving member moves the exposure member
to the retracted position, a reaction force applied from the second
moving member to the openable and closable member reaches a second
peak, and timing of the first peak is different from timing of the
second peak.
[0010] The present invention provides an image forming apparatus in
which a cartridge that supports a photosensitive member is mounted
to an image forming position, and which forms a latent image on the
photosensitive member by exposure to form an image, including: an
exposure member that includes a light emitting element arranged in
an array, and exposes the photosensitive member of the cartridge
located in the image forming position in an exposure position; an
openable and closable member that can be opened or closed with
respect to a main body of the apparatus, and can mount the
cartridge to the main body of the apparatus in a state of being
opened with respect to the main body of the apparatus; a first
moving member that is pressed and moved by the openable and
closable member when the openable and closable member is closed,
and positions the cartridge in the image forming position; and a
second moving member that is pressed and moved by the openable and
closable member when the openable and closable member is closed,
and moves the exposure member in an arrangement direction of the
cartridge and the exposure member and moves the exposure member to
the exposure position, wherein, while the openable and closable
member is being closed, when the first moving member positions the
cartridge in the image forming position, a reaction force applied
from the first moving member to the openable and closable member
reaches a first peak, and when the second moving member moves the
exposure member to the exposure position, a reaction force applied
from the second moving member to the openable and closable member
reaches a second peak, and timing of the first peak is different
from timing of the second peak.
[0011] The present invention provides an image forming apparatus in
which a cartridge that supports a photosensitive member is mounted
to an image forming position, and which forms a latent image on the
photosensitive member by exposure to form an image, including: an
exposure member that includes a plurality of light emitting
elements arranged in an array, and exposes the photosensitive
member of the cartridge located in the image forming position by
the plurality of light emitting elements in an exposure position; a
first moving member that is urged to move the cartridge in a
direction different from an insertion direction of the cartridge
into the main body of the apparatus when the cartridge is mounted
to the main body of the apparatus; and a second moving member that
is pressed by the cartridge to urge the exposure member and moved
to a positioning position to position the exposure member in the
exposure position when the cartridge is mounted to the main body of
the apparatus, wherein the cartridge is moved by the first moving
member and moved toward the image forming position, while the
cartridge is being inserted into the main body of the apparatus,
when the cartridge presses the first moving member against a force
of urging the first moving member, a reaction force applied from
the first moving member to the cartridge reaches a first peak, and
when the cartridge presses the second moving member and moves the
second moving member to the positioning position, a reaction force
applied from the second moving member to the cartridge reaches a
second peak, and timing of the first peak is different from timing
of the second peak.
[0012] The present invention provides an image forming apparatus in
which a cartridge that supports a photosensitive member is mounted
to an image forming position, and which forms a latent image on the
photosensitive member by exposure to form an image, including: an
exposure member that includes a plurality of light emitting
elements arranged in an array, and exposes the photosensitive
member of the cartridge located in the image forming position by
the plurality of light emitting elements in an exposure position;
an openable and closable member that can be opened or closed with
respect to the main body of the apparatus, and can mount the
cartridge to the main body of the apparatus in a state of being
opened with respect to the main body of the apparatus; a first
moving member that is urged to move the cartridge toward the image
forming position in a direction different from an insertion
direction of the cartridge into the main body of the apparatus when
the cartridge is inserted into the main body of the apparatus; and
a second moving member that is pressed by the openable and closable
member and urges the exposure member, the second moving member
moved to a positioning position to position the exposure mechanism
in the exposure position, wherein the cartridge to be inserted into
the main body of the apparatus presses the first moving member
against a force of urging the first moving member, and is moved
toward the image forming position in the direction different from
the insertion direction of the cartridge into the main body of the
apparatus, and when the openable and closable member is closed, the
openable and closable member presses the second moving member and
moves the second moving member to the positioning position.
[0013] Further features of the present invention will become
apparent from the following description of exemplary embodiments
with reference to the attached drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1A is a perspective view of an electrophotographic
image forming apparatus.
[0015] FIG. 1B is a vertical sectional left side view of the
apparatus.
[0016] FIG. 2A is a partial enlarged view of FIG. 1B.
[0017] FIG. 2B is a perspective view of an apparatus in a state
where a front door is opened and a top process cartridge is removed
or mounted.
[0018] FIG. 3A is an appearance perspective view of a cartridge
with a drum shutter being opened, seen from the front.
[0019] FIG. 3B is an appearance perspective view of the cartridge
in FIG. 3A seen from the back.
[0020] FIG. 4A illustrates mounting and removal of the
cartridge.
[0021] FIG. 4B illustrates positioning of an LED unit.
[0022] FIG. 5A illustrates a configuration of a cartridge
guide.
[0023] FIG. 5B illustrates positioning of the cartridge.
[0024] FIG. 6A illustrates an interlocking operation.
[0025] FIG. 6B illustrates positioning in a direction perpendicular
to a removal direction of the cartridge.
[0026] FIG. 7 illustrates an interlocking mechanism.
[0027] FIG. 8 illustrates an interlocking operation of a rod and a
cartridge pressing lever.
[0028] FIGS. 9A and 9B illustrate a toggle mechanism and an
operation thereof.
[0029] FIG. 10 illustrates an interlocking mechanism of a door and
the rod.
[0030] FIG. 11 illustrates a state of the rod and each lever when
the door is closed.
[0031] FIG. 12A is a perspective view of the apparatus in a
half-open state with the door being slightly opened.
[0032] FIG. 12B is a perspective view of the apparatus in a
half-open state with the door being further opened.
[0033] FIG. 13 illustrates a state of the rod and each lever when
the door is slightly opened.
[0034] FIG. 14 illustrates a state of the rod and each lever when
the door is further opened.
[0035] FIG. 15 illustrates a state of the rod and each lever when
the door is opened to an open position.
[0036] FIGS. 16A and 16B illustrate a configuration of the
electrophotographic image forming apparatus.
[0037] FIG. 17 is an enlarged cross sectional view on a tip side of
an LED unit located in an exposure position.
[0038] FIG. 18 illustrates a toggle mechanism and an operation
thereof.
[0039] FIG. 19 is a schematic sectional view of a general
configuration of the image forming apparatus.
[0040] FIG. 20 is a schematic sectional view of the cartridge and
therearound in the image forming apparatus.
[0041] FIG. 21 is a perspective view of the image forming apparatus
when the cartridge is mounted, seen obliquely from the front.
[0042] FIG. 22 is a schematic perspective view of the cartridge and
therearound in the image forming apparatus.
[0043] FIG. 23 is a partial sectional view of the image forming
apparatus when the cartridge is mounted or removed.
[0044] FIG. 24 is a partial sectional view of the image forming
apparatus when the cartridge is mounted or removed.
[0045] FIG. 25 is a partial sectional view of the image forming
apparatus when the cartridge is mounted or removed.
[0046] FIG. 26 is a partial sectional view of the image forming
apparatus when the cartridge is mounted or removed.
[0047] FIG. 27 is a partial sectional view of the image forming
apparatus when the cartridge is mounted.
[0048] FIG. 28A is a graph illustrating an operation force required
when the cartridge presses a pull-up member and a push-up member in
insertion of the cartridge.
[0049] FIG. 28B is a graph illustrating an operation force when the
cartridge presses an LED push-up cam in insertion of the
cartridge.
[0050] FIG. 28C is a graph illustrating an operation force in
insertion of the cartridge.
[0051] FIG. 29 is a perspective view of the image forming apparatus
seen obliquely from the front.
[0052] FIG. 30 is a partial sectional view of the image forming
apparatus when the cartridge is mounted or removed.
[0053] FIG. 31 is a partial sectional view of the image forming
apparatus when the cartridge is mounted.
[0054] FIGS. 32A and 32B are perspective views of an inner openable
and closable member and a part of the image forming apparatus
around a cartridge guide, seen obliquely from above.
[0055] FIG. 33 is a sectional view of the cartridge and therearound
in the image forming apparatus seen in an axial direction of a
photosensitive drum.
[0056] FIG. 34 is a partial perspective view of the image forming
apparatus in which the cartridge is placed on a guide member drawn
from a main body.
[0057] FIG. 35 is a partial sectional view of the image forming
apparatus when the cartridge is mounted or removed.
[0058] FIGS. 36A, 36B, 36C and 36D are partial sectional views of
the image forming apparatus when the cartridge is mounted or
removed.
DESCRIPTION OF THE EMBODIMENTS
[0059] Preferred embodiments of the present invention will now be
described in detail in accordance with the accompanying
drawings.
Embodiment 1
[0060] {General Configuration of Electrophotographic Image Forming
Apparatus}
[0061] FIG. 1A is a perspective view of an electrophotographic
image forming apparatus 100 according to this embodiment, and FIG.
1B is a vertical left side view of the apparatus 100. FIG. 2A is a
partial enlarged view of FIG. 1B, and FIG. 2B is a perspective view
of the apparatus 100 in a state where a front door is opened and a
top process cartridge is removed or mounted. The apparatus 100 is
an in-line color electrophotographic image forming apparatus that
forms a color image on a recording medium in a state where four
process cartridges each including an electrophotographic
photosensitive drum are removably mounted to corresponding
cartridge mounting portions in a main body. As an image exposure
apparatus (exposure unit) that exposes an electrophotographic
photosensitive drum, an LED unit (a light emitting member: an LED
head array, an LED exposure apparatus) is used. More specifically,
the apparatus 100 is a four-full-color LED printer using an
electrophotographic process. The apparatus 100 forms a color image
on a recording medium S based on electric image information (image
signal) input from a host apparatus H such as a personal computer,
an image leader or a counterpart facsimile apparatus to a control
circuit portion 101.
[0062] In the description below, a front side (front face side) of
the apparatus 100 is a side into and from which a feed cassette 12
on which recording mediums S are stacked and housed is inserted and
removed. A rear side (back side) is a side opposite to the
insertion and removal side. A lower side is a side on which the
feed cassette 12 is provided. Front and rear directions are a
direction from the rear side to the front side of the apparatus
(front direction) and a direction opposite thereto (rear
direction). Left and right are taken from the front side of the
apparatus. Left and right directions are a direction from right to
left (left direction), and a direction opposite thereto (right
direction). Top and bottom are taken in a gravity direction. A main
body (body) 100A is a component of the apparatus 100 except the
process cartridge. A recording medium S includes, for example,
paper, an OHT sheet, an envelope, a post card or a label
(hereinafter referred to as a recording material) on which an image
is formed by the apparatus 100.
[0063] In the body 100A, first to fourth cartridge mounting
portions 102 (102Y, 102M, 102C and 102K) are provided in order from
bottom to top in an oblique direction inclined rearward with
respect to a vertical direction. The mounting portions 102 have the
same configuration, and each includes a cartridge guide (cartridge
holding member) 71 to which a process cartridge P is removably
mounted. The guide 71 is secured and provided on a frame 104
forming a structure of the body 100A. An LED unit 6 is swingably
provided inside the each guide 71. First to fourth process
cartridges P (PY, PM, PC and PK) containing developers of different
colors are removably mounted to the mounting portions 102. The
first cartridge PY is located at a bottom, and the second cartridge
PM is located above the first cartridge PY. The third cartridge PC
is located above the second cartridge. Each cartridge P includes an
electrophotographic photosensitive drum 1 and a developing unit 3
for image visualizing (developing) an electrostatic latent image
formed on the drum 1 with a developer (toner) into a developer
image (toner image). The cartridges P have the same
electrophotographic process mechanism except containing developers
of different colors. In the cartridge P in this embodiment, the
drum 1, and a charging unit 2, a developing unit 3, and a cleaning
unit 4 as process units that act on the drum 1 are integrated into
the cartridge in a predetermined relative arrangement in a
cartridge frame 5. The drum 1 is rotatably supported by the frame 5
via a bearing member (not shown). The cartridge P is an assembly
with a rotation axis direction of the drum 1 in a longitudinal
direction, one end side of the drum 1 in the rotation axis
direction is a drive side, and the other end side is a non-drive
side. The charging unit 2 is a unit that uniformly charges a
peripheral surface of the drum 1 to predetermined polarity and
potential, and a charging roller that is a contact charging member
is used as the charging unit 2. The developing unit 3 includes a
developing roller 3a as a developing member for applying a
developer to the drum 1, a feed roller 3b for feeding the developer
to the developing roller 3a, and a developer containing portion 3c
that contains a powder developer (not shown). The cleaning unit 4
is a unit for removing a transfer residual developer from a drum
surface after a developer image is transferred to the recording
material S, and includes a cleaning blade 4a as a cleaning member,
a waste developer containing portion 4b, and the like. The first
cartridge PY contains a yellow (Y) developer in the containing
portion 3c, and forms a yellow developer image on a surface of the
drum 1. The second cartridge PM contains a magenta (M) developer in
the containing portion 3c, and forms a magenta developer image on
the surface of the drum 1. The third cartridge PC contains a cyan
(C) developer in the containing portion 3c, and forms a cyan
developer image on the surface of the drum 1. The fourth cartridge
PK contains a black (K) developer in the containing portion 3c, and
forms a black developer image on the surface of the drum 1.
[0064] In a state where each cartridge P is mounted to a
corresponding mounting portion 102 and positioned in a
predetermined image forming position C with respect to the body
100A, a drive output portion (not shown) of the body 100A is
connected to a drive input portion 59 (FIG. 6B) of the cartridge P.
The image forming position C of the cartridge P is a position for
forming an image on the recording material S. A bias output portion
(not shown) of the body 100A is connected to a bias input portion
(not shown) of the cartridge P. An LED unit 6 is positioned in an
exposure position D for exposing the drum 1 in a backward of the
drum 1 with respect to each cartridge P positioned in the image
forming position C. Positioning of the cartridge P and the unit 6
will be described later. FIG. 17 is an enlarged cross sectional
view on a tip side of the unit 6 located in the exposure position
D. The unit 6 is a light emitting member that is provided in a
rotation axis direction (longitudinal direction) of the drum 1, and
has a plurality of LEDs (light emitting diodes) 6a as light
emitting elements that emit light according to image information
for exposing the drum 1. The unit 6 includes an LED substrate 6b,
and a SELFOC.TM. lens 6c. The lens 6c is a lens for converging a
light emitted from the LED 6a and exposing the drum 1. The unit 6
is an exposure unit that selectively controls light emission of the
plurality of LEDs 6a according to image information input from the
control circuit portion 101, and performs main scanning exposure of
the surface of the rotating drum 1 charged by the charging roller 2
to form an electrostatic latent image corresponding to the image
information. In the apparatus 100 of this embodiment, the unit 6
outputs a light L (LY, LM, LC and LK) modulated according to image
information of each of the colors of Y, M, C and K input from a
host apparatus H to the control circuit portion 101 and performs
scanning exposure of the drum 1 in the cartridge P of a
corresponding color. The unit 6 as a light emitting member is
positioned in the exposure position D with the cartridge P being
positioned in the image forming position C. A plurality of units 6
are arranged in the longitudinal direction of the drum 1, and
include a plurality of light emitting elements that expose
according to the image information for exposing the drum 1.
[0065] A transfer unit 7 is provided on a front side of first to
fourth mounting portions 102 (102Y, 102M, 102C and 102K) to which
the cartridges P are removably mounted. The unit 7 includes a
driving roller 8 and a driven roller 9 provided in upper and lower
positions and parallel to each other, an endless conveyor belt 10
looping around the rollers 8 and 9, and four transfer rollers
(transfer members) 11 corresponding to the drum 1 of each cartridge
P. The belt 10 is driven by the driving roller 8, and circulated at
a predetermined speed in a counterclockwise direction shown by
arrow so as to face and be brought into contact with all the drums
1 of the cartridges P mounted to the mounting portions 102. With
the unit 7 being positioned in a predetermined transfer position H
in the body 100A, each roller 11 abuts against an inner surface of
the belt so as to interpose the belt 10 between the roller and the
corresponding drum 1 of each cartridge P positioned in the image
forming position C. In each cartridge P, a contact portion (nip
portion) between the drum 1 and the belt 10 is a transfer portion
T. The roller 11 is a transfer member for transferring, to the
recording material S, a developer image formed on the drum 1 using
the developing unit 3.
[0066] A cassette 12 is provided on a lower side of the body 100A.
Sheet-like recording materials S are stacked in the cassette 12.
The cassette 12 can be inserted or removed from the front side of
the apparatus 100 (front loading). Arrows F and G show a drawing
direction and an insertion direction of the cassette 12. For the
recording materials S in the cassette 12, the feed roller 13 is
driven to separate and feed one top recording material S forward in
the body 100A in cooperation with a separation member (not shown).
The recording material S is guided upward by a guide and registered
by a pair of registration rollers 14 provided in a downward of the
unit 7. A fixing apparatus 15 is provided in an upward of the unit
7. The fixing apparatus 15 fixes an unfixed developer image formed
on the recording material S as a fixed image by applying heat and
pressure. A discharge tray 17 that receives a recording material on
which an image has been formed from a discharge port 16 is provided
on an upper surface of the body 100A.
[0067] An operation for forming a full-color image is as described
below. The drum 1 of each cartridge P is rotationally driven at a
predetermined speed in a clockwise direction shown by arrow based
on an image forming start signal. The belt 10 is also rotationally
driven at a speed corresponding to the speed of the drum 1 in a
counterclockwise direction shown by arrow (forward in drum
rotation). The roller 13 is driven to separate and feed one
recording material S from the cassette 12, and the recording
material S is registered by the pair of rollers 14 and fed out to a
surface of an upward belt portion of the belt 10 from the side of
the driven roller 9 of the unit 7. The recording material S is
electrostatically adsorbed by a belt surface and conveyed upward by
movement of the belt 10. In each cartridge P, a predetermined
charging bias is applied to the roller 2 at predetermined control
timing to uniformly charge the surface of the drum to predetermined
polarity and potential. The unit 6 selectively controls light
emission of the plurality of LEDs as light emitting elements
according to image information input from the control circuit
portion 101, and performs main scanning exposure of the surface of
the drum 1 charged by the roller 2. Thus, an electrostatic latent
image according to image information of corresponding color is
formed on the surface of each drum 1. The formed latent image is
developed as a developer image by the roller 3a. A predetermined
development bias is applied to the roller 3a at predetermined
control timing. By the above operation of the electrophotographic
image forming process, a yellow developer image corresponding to a
yellow component of a full-color image is formed on the drum 1 of
the first cartridge PY. A magenta developer image corresponding to
a magenta component of the full-color image is formed on the drum 1
of the second cartridge PM. A cyan developer image corresponding to
a cyan component of the full-color image is formed on the drum 1 of
the third cartridge PC. A black developer image corresponding to a
black component of the full-color image is formed on the drum 1 of
the fourth cartridge PK. Specifically, by the operation of the
predetermined electrophotographic image forming process, the
developer images corresponding to the color components of the
full-color image are formed on the drums 1 of the cartridges P of
the respective colors. The developer images are electrostatically
adsorbed by the belt 10 and successively superimposed on and
transferred to the surface of the recording material S successively
passing through transfer portions T of the cartridges P. A transfer
bias of predetermined potential with polarity opposite to charging
polarity of the developer is applied from a power supply portion
(not shown) to the roller 11. Thus, unfixed developer images of
full-color including four colors: yellow, magenta, cyan and black
superimposed are formed on the surface of the recording material S
having fed out of the transfer portion T of the fourth cartridge
PK. In each cartridge P, the developer remaining on the surface of
the drum 1 after the transfer is removed by the cleaning unit 4.
The recording material S fed out of the transfer portion T of the
fourth cartridge PK is separated from the surface of the belt 10 by
a curvature of the roller 8 and introduced into the fixing
apparatus 15, and the unfixed developer image is undergoes fixing
treatment on the recording material S. Then, the recording material
S is fed out of the fixing apparatus 15 and discharged from the
discharge port 16 onto the tray 17 as a full-color image formed
material. The unit 7 transfers the image formed on the drum 1 to
the recording material S fed from the lower cassette (feed unit) 12
in the body 100A and conveys the recording material S upward. After
the developer image is fixed on the recording material S, the
recording material S is discharged to the outside of the body
100A.
[0068] {Cartridge}
[0069] FIG. 3A is an appearance perspective view of the cartridge P
with a drum shutter 52 being opened, seen from the front. FIG. 3B
is an appearance perspective view of the cartridge P seen from the
back. On left and right sides of the frame 5, handles 51L and 51R
provided to protrude on the front side of the cartridge, positioned
portions 52L and 52R coaxial with the rotation axis of the drum 1,
and insertion guide portions 53L and 53R are symmetrically
provided. An exposing groove 55 into which the unit 6 fits is
provided on a back side of the cartridge. The exposing groove 55
with a concave shape is provided in the cartridge P and forms a
space through which the light for exposing the photosensitive drum
1 passes. The shutter is a member for protecting the drum 1, and
can be manually opened/closed with respect to the frame 5 by an
opening/closing mechanism (not shown) in this embodiment.
Specifically, the shutter 52 can be closed to a closed position
(position shown by a dash-double-dot line in FIG. 4A) to hide a
drum outer exposure opening window 54 on the front side of the
cartridge, and opened to an opened position (position shown by a
solid line in FIG. 3A) shifted downward from the window 54. When
the cartridge P is mounted to the body 100A, the shutter 52 is
opened. When the cartridge P is removed from the body 100A, the
shutter 52 is closed to hide and protect the drum 1. The shutter 52
of each cartridge P is opened in a state where each cartridge P is
mounted to a corresponding mounting portion 102. In a state where a
front door (openable and closable member) 31 described later is
closed to a closed position A with respect to the body 100A, the
belt 10 of the unit 7 positioned in the transfer position H is
brought into contact with a front outer exposure portion of the
drum 1 of each cartridge P. The shutter 52 may be automatically
opened/closed in conjunction with an opening/closing operation of
the door 31. Specifically, when the cartridge P is inserted into
the mounting portion 102 and the door 31 is closed to the closed
position A, the shutter 52 is automatically moved from the closed
position to the opened position by an interlocking member that
interlocks with the closing operation of the door 31. When the door
31 is opened to an opened position B, the shutter 52 can be
automatically moved from the opened position to the closed
position.
[0070] {Cartridge Replacing Method}
[0071] As each cartridge P mounted to the apparatus 100 is used for
image forming, the contained developer (toner) is consumed. Thus,
for example, a unit (not shown) for detecting a remaining amount of
developer in each cartridge P is provided, and the control circuit
portion 101 compares a detected value of the remaining amount with
a preset threshold for a life notice or a life warning of a
cartridge. For a cartridge with the detected value of the remaining
amount smaller than the threshold, a display portion (not shown)
displays a life notice or a life warning of the cartridge. This
promotes a user to prepare for a replacement cartridge, or promotes
the user to replace the cartridge to maintain quality of an output
image.
[0072] In the apparatus 100 of this embodiment, the cartridge P is
replaced by a front access method for improving usability. On the
front side of the body 100A, an opening portion 103 is provided
through which each cartridge P is inserted into and removed from
the corresponding mounting portion 102. A front door (front cover:
an exterior member of the apparatus 100) 31 is provided as an
openable and closable member movable between the closed position A
for closing the opening portion 103 and the opened position B (FIG.
2B) for opening the opening portion 103. In this embodiment, the
door 31 is an operation member operated by the user when mounting
the cartridge to the body 100A. In this embodiment, the door 31 is
pivotable around a lower shaft (hinge shaft) 31b so as to be
opened/closed with respect to the body 100A, and can be pivoted to
a raised direction around the hinge shaft 31b and closed with
respect to the opening portion 103 as shown in FIGS. 1A and 1B. The
door 31 is closed to close the opening portion 103. The door 31 in
the closed position A is held in the position by a latching
mechanism or a toggle mechanism (not shown). The door 31 in the
closed position A is pivoted around the shaft 31b by the user
placing his/her fingers on the handle 31a to release the latch or
against a toggle force so as to substantially horizontally lay the
door 31 forward of the main body 100A. Thus, as shown in FIG. 2B,
the door 31 can be moved to the opened position B. The door 31
moved to the opened position B is held in the position. In this
embodiment, the unit 7 is opened/closed together with the door 31
with respect to the opening portion 103 in conjunction with the
opening/closing operation of the door 31. Thus, the door 31 is
moved to the opened position B, and thus the front side of each
mounting portion 102 is opened, and the front side of the cartridge
P mounted to each mounting portion 102 is exposed to the opening
portion 103.
[0073] The unit 7 is positioned in the predetermined transfer
position H where the image can be transferred to the recording
material S with respect to each cartridge P positioned in the image
forming position C in a state where the door 31 is in the closed
position A. When the door 31 in the closed position A is pivoted in
the opening direction around the shaft 31b by releasing the latch
or against the toggle force, a door switch (kill switch: not shown)
is turned off, and a power supply circuit (not shown) of the
apparatus 100 is held in an opened state. In an initial stage of
opening pivot of the door 31, an interlocking mechanism (not shown)
that interlocks with the opening operation of the door 31 releases
connection between a drive input portion (not shown) of the unit 7
and a drive output portion (not shown) of the main body 100A.
Connection between a drive input portion 59 (FIG. 6B) of the
cartridge P and a drive output portion (not shown) of the main body
100A is also released. When the door 31 including the unit 7 is
opened to the opened position B, the opening portion 103 of the
body 100A is widely opened to provide accessibility to the mounting
portion 102. The door 31 is opened to the opened position B to
release positioning of the cartridge P with respect to the body
100A as described later. Also, the unit 6 is moved from the
exposure position D (FIG. 2A) for the drum 1 to a retracted
position E (FIG. 4A) and held in the retracted position E. Each
cartridge P mounted to the mounting portion 102 is removed by
holding the left and right handles 51L and 51R protruding from left
and right sides of the cartridge P to the front side of the
cartridge by left and right hands, and drawing the cartridge P
forward from the mounting portion 102. Each cartridge P is drawn by
sliding the left and right insertion guide portions 53L and 53R of
the cartridge P in left and right guide groove portions 71a (FIG.
5A) in the guide 71. By drawing the cartridge P to move it, the
unit 6 is drawn from the exposing groove 55, and the cartridge P is
removed from the main body 100A. In FIG. 4A, arrow Y shows a
removal direction of the cartridge P. The shutter 52 is manually
closed before drawing or after removal of the cartridge P.
[0074] The cartridge P is mounted to the mounting portion 102 by
holding the left and right handles 51L and 51R of the cartridge P
to hold the cartridge P, and inserting a back side of the cartridge
into the guide (body side guide) 71 of the mounting portion 102.
This insertion is performed by respectively engaging the left and
right insertion guide portions (cartridge side guides) 53L and 53R
of the cartridge P with the left and right guide groove portions
71a of the guide 71 and sliding the guide portions 53L and 53R in
the guide groove portions 71a. In FIG. 4A, arrow X is a mounting
direction of the cartridge P. By insertion of the cartridge P, the
unit 6 located in the retracted position E fits into the exposing
groove 55. Then, when the cartridge P is sufficiently inserted, the
left and right positioned portions 52L and 52R are received by the
left and right positioning portions 105 (recess in FIG. 5B) of the
frame 104 to prevent further insertion. The shutter 52 of the
cartridge P is manually opened before or after the cartridge P is
inserted into the body 100A.
[0075] After the cartridge P is replaced by a new one, the door 31
including the unit 7 is pivoted from the opened position B to the
closed position A. By an operation of an interlocking member 80
(FIG. 6A) described later interlocking with the closing operation
of the door 31, each cartridge P is positioned with respect to the
frame 104. The positioning position is the image forming position C
of the cartridge P. The unit 6 is moved from the retracted position
E to the exposure position D and positioned with respect to the
cartridge P positioned in the image forming position C. The unit 7
is positioned in the transfer position H with respect to the body
100A. Specifically, the belt 10 of the unit 7 is brought into
contact with an exposed portion outside the front of the drum 1 of
each cartridge P positioned in the image forming position C. The
door 31 closed to the closed position A is held in the position by
a latching mechanism or a toggle mechanism (not shown). In this
state, the door switch is turned on, and the power supply circuit
of the apparatus 100 is held in a closed state. The drive output
portion of the main body is connected to the drive input portion 59
of the cartridge P. A bias output portion of the main body 100A is
connected to a bias input portion of the cartridge P. The drive
output portion of the main body is connected to the drive input
portion of the unit 7. The bias output portion of the main body
100A is connected to the bias input portion of the unit 7. In this
state, the apparatus 100 can perform an image forming
operation.
[0076] {Positioning Configuration of Cartridge P and Unit 6}
[0077] The unit 6 is supported by a support member (light emitting
member support) 61. The guide 71 includes shaft portions 72
respectively protruding in a cartridge removal direction Y at left
and right portions inside a rear plate. Guide holes 62 on left and
right sides of the support 61 fit on the left and right shaft
portions 72. Thus, the support 61 is supported by the guide 71 so
as to be movable (swingable) along the shaft portion 72 in the
cartridge insertion direction X and the cartridge removal direction
Y opposite thereto in the guide 71. A coil spring (biasing member
or elastic member) 73 is externally fitted to a base of the shaft
portion 72 between the support 61 and the guide 71. The support 61
is moved by a predetermined amount in the cartridge removal
direction Y by a biasing force (elastic force) of the spring 73 in
a free state. With this configuration, the unit 6 is supported by
the support 61 so as to be located in the exposure position D where
the light emitting element emits light to expose the drum 1, and
the retracted position E where the unit 6 is retracted from the
exposure position D. In a state where the cartridge P is positioned
in the image forming position C, the position in the cartridge
removal direction X in the exposure position D of the unit 6 is
determined as described below. Specifically, the position is
determined by the support 61 abutting against a drum cover 56 that
positions the drum 1 as shown in FIG. 4B by a biasing force of the
spring 73. The direction perpendicular to the cartridge removal
direction X of the unit 6 and the axial direction of the drum 1 are
determined by engagement between the guide hole 62 and the shaft
portion 72. The support 61 includes protrusions 63 (63Y, 63M, 63C
and 63K) extending to the outside of the body frame 104 as shown in
FIG. 7. The protrusion 63 is pressed in the cartridge insertion
direction X by a rotatable lever 91 (91Y, 91M, 91C and 91K) against
the biasing force of the spring 73. Thus, the support 61 is moved
inward (rearward) of the body and retracted away from the drum
cover 56. Specifically, the unit 6 is moved from the exposure
position D to the retracted position E and held in the retracted
position E. The lever 91 is away from the protrusion 63 in a state
where the apparatus 100 can perform an image forming operation. At
that time, as shown in FIG. 6A, the lever 91 is urged in the arrow
direction (clockwise direction) by an elastic force of the spring
(elastic member) 20 and abuts against the shaft 21 embedded in the
frame 104. In this state, the support 61 is moved in the cartridge
removal direction Y by a biasing force of the spring 73, and the
support 61 abuts against the drum cover 56. Thus, the unit 6 is
moved from the retracted position E to the exposure position D and
positioned in the exposure position D (FIG. 4B).
[0078] The lever 91 is a light emitting member positioning member
(light emitting member pressing member) for positioning (pressing)
the support 61 so that the unit 6 is positioned in the exposure
position D. The lever 91 is moved between a positioning position
(pressing position for pressing) Q where the support 61 is pressed
and positioned so that the unit 6 is positioned in the exposure
position D and a retracted position R where the lever 91 is
retracted from the positioning position Q. A rod (interlocking
member) 80 slidable in an upward direction shown by arrow J and a
downward direction shown by arrow K opposite to the upward
direction is placed outside the frame 104. The rod 80 is vertically
moved in conjunction with the opening/closing operation of the door
31 as described later. The vertical movement of the rod 80 performs
pressing release and pressing of the protrusion 63 by the lever 91.
Specifically, the unit 6 is moved between the exposure position D
and the retracted position E.
[0079] Next, positioning of the cartridge P will be described. The
position of the cartridge P in the insertion direction X is
determined by the left and right positioned portions 52L and 52R
being received by the left and right positioning portions 105 of
the frame 104 as shown in FIG. 5B. The position of the cartridge P
in the removal direction Y is determined by a projection 57 of the
drum cover 56 being pressed by a biasing force of a pivotable
cartridge pressing lever 120 placed on the frame 104. The lever 120
is a cartridge positioning member (cartridge pressing member for
pressing the cartridge P in the image forming position C) for
positioning the cartridge P in the image forming position C. By the
pressing, the positioned portions 52L and 52R of the cartridge P
are pressed against the positioning portion 105 and the cartridge P
is positioned and held in the image forming position C. The
direction perpendicular to the removal direction Y of the cartridge
P is determined as shown in FIG. 6B. Specifically, the direction is
determined in such a manner that the cartridge P is rotated around
the drive input portion 59 by a rotation drive force input from the
drive output portion (not shown) to the drive input portion of the
cartridge P, and the protrusion 58 of the cartridge P abuts against
the abutment surface 106 of the frame 104.
[0080] Pressing and pressing release of the cartridge P by the
lever 120 are also performed in conjunction with sliding of the rod
80 like pressing and pressing release of the unit 6. As shown in
FIG. 8, the rod 80 is slid downward shown by arrow K, and thus a
cartridge pressing abutment portion 80b on a back surface (body
inner surface) of the rod 80 abuts against an upper surface of the
protrusion 120a of the lever 120. Thus, the lever 120 is pivoted in
a direction away from the projection 57 of the cartridge P.
Specifically, the lever 120 is moved from the positioning position
(pressing position for pressing) M where the cartridge P is pressed
and positioned in the image forming position C to the retracted
position N where the cartridge P is retracted, and pressing of the
positioned portions 52L and 52R of the cartridge P against the
positioning portion 105 is released. On the other hand, the rod 80
is slid upward shown by arrow J, the abutment portion 80b of the
rod 80 abuts against the lower surface of the protrusion 120a of
the lever 120 to press the lever 120. Thus, the lever 120 is
pivoted in the direction toward the projection 57 of the cartridge
P, and the positioned portions 52L and 52R of the cartridge P are
pressed against the positioning portion 105. Specifically, the
lever 120 is moved from the retracted position N to the positioning
position M where the cartridge P is pressed and positioned in the
image forming position C, and the positioned portions 52L and 52R
of the cartridge P are pressed against the positioning portion 105.
As shown in FIG. 9A, the lever 91 is urged in the clockwise
direction by a lever spring (elastic member) 93 (toggle mechanism),
and the lever 120 is urged in the counterclockwise direction by a
pressing lever spring (elastic member) 121 (toggle mechanism). When
the levers are pivoted by a certain angle or more, as shown in FIG.
9B, the urging directions are changed by the toggle mechanisms.
Specifically, the lever 91 and the lever 120 are urged (pressed) by
the toggle mechanisms 93 and 121.
[0081] An interlocking mechanism between the door 31 and the rod 80
will be described. As shown in FIG. 10, the door 31 includes a door
gear 23 concentric with the lateral shaft 31b (FIG. 1B) as a center
of opening/closing. The gear 23 is rotated around the lateral shaft
31b integrally with the door 31 along with the opening/closing
operation of the door 31. An intermediate link gear 25 meshes with
the door 31 via an idler gear 24. An intermediate link 26 is
provided concentrically integrally with the gear 25. The link 26
engages a door link arm 27. The gear 24, the gear 25, the link 26
and the arm 27 are pivotally supported on the frame 104. In
conjunction with the opening operation of the door 31 from the
closed position A to the opened position B, the gear 23 is rotated
in the counterclockwise direction shown by arrow, the gear 24 is
rotated in the clockwise direction shown by arrow, the gear and the
link 26 are rotated in the counterclockwise direction shown by
arrow, and the lever 27 is rotated in the clockwise direction shown
by arrow. The arm 27 has a shape to press the protrusion 81 of the
rod 80, and the rod 80 is slid downward shown by arrow K by an
amount according to the rotation angle of the arm 27. In reverse,
the rod 80 is slid upward in conjunction with the closing operation
of the door 31.
[0082] The operation of releasing pressing of the cartridge P and
the operation of retraction of the unit 6 in conjunction with the
opening operation of the door 31 by the user and operation timings
thereof will be described. The door 31 is closed in a printable
state of the apparatus 100 (FIGS. 1A and 1B). In this state, as
shown in FIG. 11, a protrusion 92 of the lever 91 is away from the
pressure release abutment portion 80a, and the abutment portion 80b
is away from the protrusion 120a of the lever 120. In this state,
the cartridge P is pressed by the lever 120 and positioned and held
in the image forming position C. The unit 6 is pressed against the
cartridge P positioned in the image forming position C by the
biasing force of the spring 73 and positioned in the exposure
position D.
[0083] When the user opens the door 31 for cartridge replacement or
jam treatment, a latch (not shown) of the door 31 engaging a member
(not shown) provided on the body 100A is released, and the door 31
can be turned to the opened position B. FIG. 12A illustrates a
half-open state with the door 31 slightly opened, and FIG. 12B
illustrates a half-open state with the door 31 further opened. When
the door 31 is pivoted from the state in FIG. 12A, as described
above, the rod 80 is slid downward shown by arrow K. When the door
31 is pivoted by a certain angle, as shown in FIG. 13, the abutment
portion 80a of the rod 80 abuts against and presses the protrusion
92 of the lever 91, and the retraction operation of the unit 6 is
completed. The unit 6 is held by the toggle mechanism 93 with
pressing being released by the spring urging direction being
changed from that in FIG. 9A to that in FIG. 9B. At this time, the
lever 120 has not yet been pivoted as shown in FIG. 13.
Specifically, the lever 120 is positioned in the positioning
position M where the cartridge P is positioned in the image forming
position C. Further, when the rod 80 is slid downward, as shown in
FIG. 14, the abutment portion 80b abuts against and presses the
protrusion 120a to release pressing of the cartridge P. When the
rod 80 is further slid downward, as shown in FIG. 15, the lever 120
is retracted from a cartridge removal path. The lever 120 is held
by the toggle mechanism 121 with pressing being released by the
spring urging direction being changed from that in FIG. 9A to that
in FIG. 9B. Specifically, the lever 120 is moved from the
positioning position M to the retracted position N. The door 31
including the unit 7 is moved to the opened position B to widely
open the opening portion 103, and each cartridge P is exposed from
the opening portion 103 and can be removed to the outside of the
body 100A.
[0084] An operation will be described when the door 31 including
the unit 7 is closed after the cartridge replacement or the jam
treatment is finished. With the door 31 being opened, the
protrusion 92 of the lever 91 abuts against the abutment portion
80a of the rod 80, and the abutment portion 80b of the rod 80 abuts
against the protrusion 120a of the lever 120 (FIG. 15). In this
state, pressing of both the cartridge P and the unit 6 is released
(positioning release). When the door 31 is closed, the rod 80 is
slid upward shown by arrow J (FIG. 8) in conjunction with the
closing operation as described above. When the door 31 is pivoted
by a certain angle, the abutment portion 80b of the rod 80 is moved
away from the protrusion 120a of the lever 120 from FIG. 14 to FIG.
13 and the cartridge pressing operation is completed. Specifically,
the lever 120 is moved from the retracted position N to the
positioning position M. At this time, the lever 91 has not yet been
pivoted. Specifically, the lever 91 is positioned in the retracted
position R. When the door 31 is closed and the rod 80 is further
slid upward, the abutment portion 80a is moved away from the
protrusion 92, and the unit 6 abuts against the cartridge cover 56.
Specifically, the cartridge P is positioned in the image forming
position C, and the unit 6 is pressed against the drum cover 57 of
the cartridge P and positioned in the exposure position D. Then,
the apparatus 100 enters a printable state with the door 31 being
sufficiently closed.
[0085] In the above, the rod 80 is the interlocking member that
moves the lever 120 from the retracted position N to the
positioning position M in conjunction with the operation of the
door 31 (operation member, exterior member) to mount the cartridge
P to the body 100A. The rod is also the interlocking member that
then moves the lever 91 from the retracted position R to the
positioning position Q so that the unit 6 is positioned from the
retracted position E to the exposure position D. The rod 80 is the
interlocking member that retracts the lever 91 from the positioning
position Q to the retracted position R so that the unit 6 is
retracted from the exposure position D to the retracted position E
in conjunction with the operation of the door 31 to remove the
cartridge P from the body 100A. The rod 80 is the interlocking
member that then retracts the lever 120 from the positioning
position M to the retracted position E.
[0086] In the configuration of this embodiment, when the door 31 is
opened, a reaction force is applied from the lever 91 and the lever
120 of the toggle mechanism via the rod 80 to the door 31 in the
retraction operation of the unit 6 from the exposure position D to
the retracted position E and the positioning release operation of
the cartridge P from the image forming position C. From the
property of the toggle mechanism, the reaction force reaches a peak
immediately before an urging direction of a spring (lever spring
93, pressing lever spring 121) of the toggle mechanism changes.
[0087] In this embodiment, when the door 31 is opened, the
retraction operation of the unit 6 from the exposure position D to
the retracted position E is first performed. Then, the pressing
release operation of the cartridge P, that is, the positioning
release operation of the cartridge P from the image forming
position C is performed. When the door 31 is closed, the pressing
operation of the cartridge P, that is, the positioning operation of
the cartridge P in the image forming position C is performed. Then,
the pressing operation of the unit 6 from the retracted position E
to the exposure position D is performed. Thus, the pressing state
and the pressing release state are switched using the toggle
mechanism to change the pressing timings. This requires a smaller
opening/closing force of the door 31 as compared to the case of
simultaneous pressing. Specifically, the pressing timings are
changed, and thus reactions force applied from the lever 91 and the
lever 120 of the toggle mechanism via the rod 80 to the door 31
reach the peak at different timings. This reduces a maximum value
of an operation force required for opening/closing the door 31 as
compared to a case of simultaneously reaching the peak, thereby
improving usability.
[0088] As shown in FIG. 6A, in this embodiment, when the door 31 is
closed, the lever 91 is moved in the Q direction by the elastic
force of the spring 20 and moved from the retracted position R to
the positioning position Q. However, the lever 91 may be moved in
the Q direction and moved from the retracted position R to the
positioning position Q and held in the positioning position Q using
the lever spring 93 (FIGS. 9A and 9B) as the toggle mechanism
rather than the elastic force of the spring 20. In this case, as
shown in FIG. 18, the rod 80 includes the abutment portion 80c that
abuts against and presses the lever 91 in the J direction when the
rod 80 is moved in the J direction. Then, the abutment portion 80c
of the rod 80 may pivot the lever 91 in the Q direction from the
state where the lever 91 is urged in the R direction by the lever
spring 93 to the state where the lever 91 is urged in the Q
direction by the lever spring 93.
[0089] In this configuration, when the door 31 is closed, the rod
80 is moved in the J direction and abuts against and presses the
lever 120, and performs the positioning operation of the cartridge
P in the image forming position C. Then, the abutment portion 80c
of the rod 80 abuts against and presses the lever 91, and performs
the pressing operation of the unit 6 from the retracted position E
to the exposure position D.
[0090] When the door 31 is closed, as when the door 31 is opened,
the reaction force is applied from the lever 91 and the lever 120
of the toggle mechanism via the rod 80 to the door 31, and the
reaction force reaches the peak immediately before change of the
urging direction of the spring (lever spring 93, press lever spring
121) of the toggle mechanism.
[0091] In contrast to this, in order to change the pressing timings
of the lever 120 and the lever 91, the reactions force applied from
the lever 91 and the lever 120 of the toggle mechanism via the rod
80 to the door 31 reaches the peak at different timings. This
reduces a maximum value of an operation force required for
opening/closing the door 31 as compared to the case of
simultaneously reaching the peak, thereby improving usability.
Embodiment 2
[0092] FIGS. 16A and 16B illustrate an image forming apparatus 100
of this embodiment. The apparatus 100 of this embodiment includes
an inner cover 7A (double-sided unit) that also serves to perform
double sided conveyance between a door 31 and a transfer unit 7 in
the apparatus 100 of Embodiment 1 to enable execution of
double-sided printing. The door 31, the inner cover 7A and the
transfer unit 7 are individually pivotable around a lower hinge
shaft portion (not shown) so as to be opened/closed with respect to
a body 100A. A link lever 41 for transmitting pivot of the unit 7A
to the rod 80 is placed on a rotation center of the unit 7A. The
lever 41 is pivoted in a counterclockwise direction shown by arrow
by opening pivot of the unit 7A. The lever 41 includes a protrusion
41a, and the protrusion 41a presses a protrusion 42a of an
intermediate link 42 to pivot the link 42 in a clockwise direction
shown by arrow, and a rod pressing portion 42b of the link 42
presses a rod protrusion 81. Thus, the rod 80 is slid downward
shown by arrow K. By the closing pivot of the unit 7A, the lever
41, the link 42 and the rod 80 perform operations opposite to those
in the opening pivot of the unit 7A. In this embodiment, the door
31, the inner cover 7A and the transfer unit 7 are operation
members operated when the user mounts a cartridge to the body 100A.
In this embodiment, by vertical sliding of the rod 80 with the
opening/closing operation of the inner cover 7A in conjunction with
the operation of the inner cover 7A, cartridge pressing and
pressing release, LED unit pressing and retraction operation are
performed as in Embodiment 1. In removal of the cartridge P, the
door 31 is pivoted to be opened, and then the inner cover 7A is
pivoted to be opened. By downward sliding of the rod 80 that
interlocks with the inner cover 7A with the opening pivot, the
retraction operation of the unit 6 and the pressing release of the
cartridge P are performed. Then, the unit 7 is pivoted to be opened
to remove the cartridge P from the opening portion 103. When the
cartridge P is replaced by a new one, the unit 7 is pivoted to be
closed, and then the inner cover 7A is pivoted to be closed. By
upward sliding of the rod 80 that interlocks with the inner cover
7A with the closing/opening pivot, the pressing operation of the
cartridge P and the pressing operation of the unit 6 are performed.
The door 31 is finally closed.
[0093] In this embodiment, when the inner cover 7A is opened, the
retraction operation (movement from an exposure position D to a
retracted position E) of the unit 6 is first performed, and then
the pressing release operation (positioning releasing from an image
forming position C) of the cartridge P is performed. When the inner
cover 7A is closed, the pressing operation (positioning in the
image forming position C) of the cartridge P is first performed,
and then the pressing operation (movement from the retracted
position E to the exposure position D) of the unit 6 is performed.
The pressing state and the pressing release state are switched by a
toggle mechanism as in Embodiment 1, and pressing timings are
changed (made different). This requires a smaller opening/closing
force of the inner cover 7A as an operation member as compared to a
case of simultaneous pressing.
[0094] Other Matters
[0095] The image forming apparatuses of Embodiments 1 and 2 are
examples of an in-line color printer, but the same advantage can be
obtained for a configuration of a black-and-white printer.
[0096] As a light emitting element of the light emitting member 6,
for example, a field light emitting element such as a liquid
crystal element, a semiconductor light emitting diode or an organic
electroluminescence element (organic EL element) is used. The
semiconductor light emitting diode is a semiconductor device that
emits light in application of a voltage. The organic EL element is
an electronic material made of an organic compound that shines in
application of a voltage, and emits light by itself. For example,
in the organic EL element, an organic molecule light emitting layer
is interposed between two electrodes to apply a voltage. Thus, an
electron injected from the electrodes and a hole are recombined to
excite an organic molecule, and light is emitted when the excited
organic molecule returns to a base state.
[0097] In the present invention, the operation members operated by
the user when the cartridge P is mounted to the main body 100A are
not limited to the front door 31 in Embodiment 1 and the
double-sided unit 7A in Embodiment 2. For example, the operation
member such as a lever may be used.
[0098] In Embodiments 1 and 2, the cartridge P is positioned in the
image forming position C by pressing, but may be positioned by
pulling the cartridge P. In Embodiments 1 and 2, the unit 6 as the
light emitting member is positioned in the exposure position D by
pressing the support 61, but may be positioned by pulling the
support 61.
[0099] In Embodiments 1 and 2, the unit 6 is positioned in the
exposure position D by the support 61 abutting against the drum
cover 56. However, a positioning portion may be formed on the frame
104, and the unit 6 may be positioned in the exposure position D by
the support 61 abutting against the positioning portion of the
frame 104 like the cartridge P.
[0100] In such a positioning configuration, when the door 31 or the
inner cover A is opened, the pressing release operation of the
cartridge P, that is, the positioning release operation of the
cartridge P from the image forming position C is first performed.
Then, the retraction operation of the unit 6 from the exposure
position D to the retracted position E is performed. Such a
configuration may be allowed.
[0101] When the door 31 or the inner cover A is closed, the
pressing operation of the unit 6 from the retracted position E to
the exposure position D is first performed. Then, the pressing
operation of the cartridge P, that is, the positioning operation of
the cartridge P in the image forming position C is performed. Such
a configuration may be allowed.
[0102] With such a configuration, as in the above-described
embodiments, pressing timings of the cartridge P and the unit 6 are
changed (made different), and thus reaction forces applied from the
lever 91 and the lever 121 to the door 31 or the inner cover 7A
reach the peak at different timings. This requires a smaller
opening/closing force as compared to the case of simultaneous
pressing.
[0103] In Embodiments 1 and 2, when the door 31 or the inner cover
A is opened and closed, the pressing timings of the cartridge P and
the unit 6 are changed (made different). However, the pressing
timings of the cartridge P and the unit 6 may be changed (made
different) either when the door 31 or the inner cover A is opened
or when closed. This also requires a smaller opening/closing force
of the door 31 as compared to the case of simultaneous pressing
when the door 31 or the inner cover A is opened or closed.
[0104] The above descriptions are on Embodiments 1 and 2, and
Embodiments 3, 4 and 5 will be now described.
[0105] For an image forming apparatus 200 described in Embodiments
3, 4 and 5, a method for mounting and removing a cartridge P is
different from that for the image forming apparatus 100 of
Embodiments 1 and 2. In Embodiments 3, 4 and 5, timings of
cartridge pressing and exposure unit pressing are shifted to reduce
a force required for pressing in the image forming apparatus
200.
Embodiment 3
[0106] <General Configuration of Image Forming Apparatus
200>
[0107] A general configuration of the image forming apparatus 200
will be described. The image forming apparatus 200 of this
embodiment is an electrophotographic color image forming apparatus.
FIG. 19 is a schematic sectional view illustrating a general
configuration of the image forming apparatus 200.
[0108] In the image forming apparatus 200, a feed unit 280 is
placed at the bottom. The feed unit 280 contains sheets as
recording materials. A registration roller unit 250 that registers
and conveys the sheets is placed in an upper right of the feed unit
280. Four cartridges P (PY, PM, PC and PK) are placed above the
feed unit 280. An LED unit 230 described later is placed between
the cartridges P, and exposes a photosensitive drum 11. Above the
cartridges P, an intermediate transfer unit 240 is placed to face
the cartridges P. The intermediate transfer unit 240 includes an
intermediate transfer belt 241. Inside the intermediate transfer
belt 241, a primary transfer roller 242 (242Y, 242M, 242C and
242K), an intermediate transfer belt driving roller 243, a
secondary transfer facing roller 244, a tension roller 245 and an
intermediate transfer belt cleaning unit 246 are provided. A
secondary transfer unit 290 is placed on a right side of the
intermediate transfer unit 240, and a secondary transfer roller 291
is provided to face the secondary transfer facing roller 244. A
fixing unit 220 is placed above the intermediate transfer unit 240
and the secondary transfer roller 291. A paper discharge unit 260
is placed in an upper left of the fixing unit 220. The paper
discharge unit 260 includes a pair of paper discharge rollers 261
and a double-sided conveyor portion 262, a pair of reverse rollers
263 and a double-sided flapper 264 as a branch unit.
[0109] <Configuration of Cartridge>
[0110] Next, a configuration of a cartridge that includes members
for image forming, can be mounted to and removed from the image
forming apparatus 200, and performs image forming while being
mounted to the image forming apparatus 200 will be described. The
cartridges P (PY, PM, PC and PK) are process cartridges each
including a photosensitive drum 1 (1Y, 1M, 1C and 1K) and a process
unit that acts on the photosensitive drum. Four cartridges P (PY,
PM, PC and PK) can be mounted to and removed from the main body
200. The four cartridges P are different in forming toner images of
different colors, and respectively contain toner of yellow (Y),
magenta (M), cyan (C) and black (K). Since the four cartridges P
have the same structure other than the above, one cartridge P will
be described below as a representative. Members or the like
included in the cartridge P will be also described as
representatives.
[0111] FIG. 20 is a schematic sectional view of the cartridge P and
therearound in the image forming apparatus 200. In the cartridge P,
a cleaner unit 217 and a developing unit 214 are integrally
configured.
[0112] The cleaner unit 217 includes a photosensitive drum 1, a
charging roller 212, a cleaning blade 2161 and a waste toner
container 2162. The photosensitive drum 1 is formed by applying an
organic photoconductor layer (OPC) to an outer peripheral surface
of an aluminum cylinder. The photosensitive drum 1 is rotatably
supported by flanges at opposite ends in an axial direction, and is
rotated by a drive force applied by a drive motor (not shown) in
the main body 200.
[0113] A charging roller 212 is a conductive roller, and is abutted
against the surface of the photosensitive drum 1. In abutment, a
charging bias voltage is applied to uniformly charge the surface of
the photosensitive drum 1. Transfer residual toner remaining on the
surface of the photosensitive drum 1 after primary transfer is
removed by a cleaning blade 2161. The removed toner is collected in
the waste toner container 2162.
[0114] The developing unit 214 includes a developing roller 2142, a
toner supply/recovery roller 2143 and a toner containing portion
2144. The developing roller 2142 that applies toner to an
electrostatic latent image and develops the image as a toner image
is placed adjacent to the photosensitive drum 1, rotated by the
drive force of the drive motor (not shown) in the main body 200,
and applies a development bias voltage to perform development of
the photosensitive drum 1. The toner supplying/collecting roller
2143 supplies toner from the toner containing portion 2144 to the
developing roller 2142, and collects toner that has not been used
for development of the photosensitive drum 1.
[0115] <Configuration of LED Unit 230>
[0116] A configuration of an LED unit 230 (230Y, 230M, 230C and
230K) will be described.
[0117] The LED unit 230 is placed between the developing unit 214
and the cleaner unit 217 of each of the four cartridges P mounted
to the main body 200, exposes the photosensitive drum 1 based on
image information, and forms an electrostatic latent image on the
photosensitive drum 1. Since the four LED units 230 (230Y, 230M,
230C and 230K) have the same structure, one LED unit 230 will be
described as a representative. Members or the like included in the
LED unit 230 will be also described as representatives.
[0118] The LED unit 230 includes an LED frame 231, an LED head 232
as an exposure member, a cartridge pressing member 235 (see FIG.
23) and a pressing spring 236.
[0119] The LED head 232 include an LED array 233 in which a
plurality of LED light emitting elements are arranged in an array
in a main scanning direction according to a predetermined pixel
pitch, and a lens array 234 through which light from each LED light
emitting element of the LED array 233 passes, integrated into a
unit. The LED array 233 emits light based on image data to be
formed, applies light to the rotating photosensitive drum 1, and
exposes the photosensitive drum 1. The LED frame 231 includes the
LED head 232, a cartridge pressing member 235 and a pressing spring
236.
[0120] The LED head 232 and the cartridge pressing member 235 are
integrally formed and urged to abut against the cartridge P in the
image forming position and thus positioned in the exposure
position. Thus, the LED head 232 and the cartridge pressing member
235 are urged upward by the pressing spring 236, and supported by
the LED frame 231 so as to be freely movable by a predetermined
amount in the vertical direction (Z direction) and the axial
direction of the photosensitive drum 1 with respect to the LED
frame 231.
[0121] The LED unit 230 can be retracted from the cartridge so as
not to interfere with the movement of the cartridge P when the
cartridge P is mounted to or removed from the main body 200.
Specifically, the LED unit 230 is supported by a cartridge guide
2100 movably in the vertical direction (Z direction) via an LED
unit push-up cam 2101 (see FIG. 23).
[0122] <Image Forming Operation>
[0123] A color image forming operation of the image forming
apparatus 200 of this embodiment will be described. The image
forming operation is performed in a state where the cartridge P is
mounted to the apparatus and located in the image forming position.
As described above, the photosensitive drum 1 is driven and rotated
in an A direction (FIG. 20). In this state, the surface of the
photosensitive drum 1 is uniformly charged by the charging roller
212, and exposed by the LED unit 230, and thus an electrostatic
latent image is formed on the surface. The developing roller 2142
applies toner to the electrostatic latent image to form a toner
image on the surface of the photosensitive drum 1. A transfer bias
is applied to the toner image in a position where the surface of
the photosensitive drum 1 faces the primary transfer roller 242,
and the toner image is transferred from the surface of the
photosensitive drum 1 onto the intermediate transfer belt 241.
[0124] The toner images are transferred in a superimposed manner to
the intermediate transfer belt 241 in positions facing the
photosensitive drums (1Y, 1M, 1C and 1K), and the toner image as
superimposed images including four color toner images are formed on
the intermediate transfer belt 241. The toner images are
collectively transferred from the intermediate transfer belt 241
onto a sheet fed from the feed unit 280 at the same timing in a
position facing the secondary transfer roller 244.
[0125] The sheet to which the toner image has been transferred is
conveyed to the fixing unit 220, where the toner image is fixed on
the sheet by heating and pressurizing, and the sheet is discharged
to the outside of the apparatus by the paper discharge unit 260.
The image is formed on the sheet by the above-described
operation.
[0126] <Mounting of Cartridge P to Main Body>
[0127] Mounting of the cartridge P to the image forming apparatus
200 will be described. FIG. 21 is a perspective view of the image
forming apparatus 200 when the cartridge P is mounted, seen
obliquely from the front. In this embodiment, the cartridge P is
moved in the rotating axis direction of the photosensitive drum 1
and inserted into or drawn from the main body 200, and thus can be
mounted to or removed from the main body 200. The configuration of
mounting and removing the cartridge P is referred to as a so-called
side-oriented configuration.
[0128] When the cartridge P is mounted to the image forming
apparatus 200, the openable and closable member 270 is opened with
respect to the main body 200 to expose the opening portion 271.
Four cartridge guides 2100 (2100Y, 2100M, 2100C and 2100K) arranged
in line in a direction perpendicular to the axis of the
photosensitive drum 1 are exposed from the opening portion 271. The
cartridge P is inserted in an F direction according to the
cartridge guide 2100 so that the cartridge guide 2100 is interposed
between the cleaner unit 217 and the developing unit 214, and thus
can be mounted to the main body 200. FIG. 21 illustrates a state
where the cartridge PM has been already mounted to the main body
200, and the cartridge PY is being inserted into the main body
200.
[0129] As described above, in the configuration in which the
cartridge P is inserted into the main body 200 in the axial
direction of the photosensitive drum 1, and thus mounted to and
removed from the main body 200, the photosensitive drum 1 may rub
against a member such as the intermediate transfer belt 241 close
to the photosensitive drum 1 in the main body 200 and damage each
other in mounting and removal of the cartridge P. Thus, the
cartridge P is inserted in a state where the cartridge P is
retracted in a predetermined distance from the intermediate
transfer belt 241 or the like in the direction perpendicular to the
axis of the photosensitive drum 1.
[0130] In this embodiment, the intermediate transfer belt 241 is
placed above the photosensitive drum 1, and thus when the cartridge
P is inserted, the cartridge P is first retracted below the
intermediate transfer belt 241. Then, immediately before completion
of the insertion of the cartridge P, the cartridge P is moved
upward against the gravity, and reaches the image forming position
where the photosensitive drum 1 is close to the intermediate
transfer belt 241.
[0131] In the configuration in which the cartridge P is pushed
upward against the gravity in insertion, and thus moved in the
direction perpendicular to the axis of the photosensitive drum 1, a
larger pressing force is required than for moving the cartridge P
in other directions.
[0132] As described above, in this embodiment, the LED unit 230 is
moved upward, and the LED head 232 is pressed toward the cartridge
P to position the LED head 232 in the exposure position. Thus, if
the timing of pushing the cartridge P upward is always the same as
the timing of moving the LED unit 230 upward, reaction forces
applied to the user in mounting the cartridge P simultaneously
reach the peak, thereby increasing a load on the user.
[0133] Thus, in this embodiment, the timings of the reaction forces
applied to the user in mounting the cartridge P are shifted.
[0134] A configuration for moving the cartridge P upward and
positioning the cartridge P in the main body 200 will be described
in detail.
[0135] FIG. 22 is a schematic perspective view of the cartridge P
and therearound in the image forming apparatus 200. The cartridge P
is shown being inserted. In the apparatus, the front plate 2110 and
the rear plate 2120 are placed at opposite ends in the axial
direction (F direction) of the photosensitive drum 1 with the
cartridge P being mounted to the apparatus. At opposite ends in the
axial direction of the photosensitive drum 1 of the cartridge P,
positioned portions 213a and 213b are provided for positioning the
photosensitive drum 1 in the main body 200.
[0136] The front plate 2110 includes a pull-up member 2111 as a
first moving member that is pushed down by a pulled-up portion 2113
of the cartridge P and then pulls up the pulled-up portion 2113
immediately before completion of insertion of the cartridge P. The
pull-up member 2111 is provided rotatably around a shaft 2118, and
urged upward (Z direction) by a pull-up spring 2116 hung on a
hanging portion 2117 on the front plate 2110. The front plate 2110
has abutment portions 2112a and 2112b.
[0137] The rear plate 2120 includes a push-up member 2121 as a
first moving member that is pushed down by a pushed-up portion 2123
of the cartridge P and then pushes up the pushed-up portion 2123
immediately before completion of insertion of the cartridge P. The
push-up member 2121 is provided rotatably around a shaft 2128, and
urged upward (Z direction) by a push-up spring 2126. The rear plate
2120 has abutment portions 2122a and 2122b.
[0138] The cartridge P is moved upward by the pull-up member 2111
and the push-up member 2121 in insertion into the main body
200.
[0139] A configuration will be described of mounting the cartridge
P to the main body 200 and positioning the cartridge P in the image
forming position, and positioning the LED unit 230 and the LED head
232 on the cartridge P.
[0140] FIG. 23 is a partial sectional view of the image forming
apparatus 200 in mounting and removing the cartridge P. This
section includes the axis of the photosensitive drum 1 and is
parallel to the Z direction.
[0141] In this state, the LED unit 230 including the LED head 232
is located in a retracted position retracted downward with respect
to the photosensitive drum 1 of the cartridge P.
[0142] In this state, the cartridge P is inserted into the main
body 200 in the axial direction (F direction) of the photosensitive
drum 1. As shown in FIG. 24, the pulled-up portion 2113 of the
cartridge P first abuts against the pull-up member 2111 to rotate
the pull-up member 2111 downward around the shaft 2118 (FIG. 22).
At the same time, the pushed-up portion 2123 of the cartridge P
abuts against the push-up member 2121 to rotate the push-up member
2121 downward around the shaft 2128 (FIG. 22).
[0143] When the cartridge P is further inserted in the F direction,
as shown in FIG. 25, the pulled-up portion 2113 rides on a pull-up
surface 2114 of the pull-up member 2111. At the same time, the
pushed-up portion 2123 also rides on the push-up member 2121. As
such, the cartridge P presses the pull-up member 2111 and the
push-up member 2121, and rides thereon. Thus, biasing forces of the
pull-up spring 2116 of the pull-up member 2111 and the push-up
spring 2126 of the push-up member 2121 move the cartridge P upward
by a predetermined amount.
[0144] Further, at this time, a cam abutment surface 2103 provided
on the cartridge P abuts against a cartridge abutment surface 2102
provided in an LED unit push-up cam 2101 as a second moving
member.
[0145] When the cartridge P is further inserted in the F direction
in this state, as shown in FIG. 26, the LED unit push-up cam 2101
is pressed by the cartridge P and moved in the F direction. The cam
surface 2104 for pushing up the LED unit 230 of the LED unit
push-up cam 2101 abuts against the cam surface 2105 of the LED unit
230, and the LED unit 230 is pushed up upward (Z direction) toward
the photosensitive drum 1.
[0146] The LED unit 230 is pushed up, and thus the cartridge
push-up member 235 urged upward by the pressing spring 236 of the
LED unit 230 abuts against the cartridge P to press the cartridge
P. This further moves the cartridge P upward.
[0147] As shown in FIG. 27, the positioned portions 213a and 213b
abut against the abutment portions 2112a and 2112b of the front
plate 2110 and the abutment portions 2122a and 2122b of the rear
plate 2120. This determines the position of the cartridge P in the
vertical direction (Z direction) and the direction vertically
perpendicular to the cartridge insertion direction (F
direction).
[0148] At the same time, a part of the cartridge P abuts against
the rear plate 2120 in the cartridge insertion direction (F
direction) to determine the position in the cartridge insertion
direction (F direction).
[0149] As described above, the cartridge P reaches the image
forming position and is positioned. The cartridge pressing member
235 fits in the fitting hole 2106 of the cartridge P to position
the LED head 232 of the LED unit 230 in the main scanning direction
(F direction) and a sub scanning direction (direction perpendicular
to the F and Z directions) of the cartridge P. As such, the LED
head 232 reaches the exposure position and is positioned.
[0150] A resultant force of pressing forces of the pull-up member
2111, the push-up member 2121 and the cartridge pressing member 235
of the LED unit 230 causes a sufficient pressing force to position
the cartridge P in the image forming position and transfer the
toner image to the intermediate transfer belt 241.
[0151] In this embodiment, the cartridge P rides on the pull-up
member 2111 and the push-up member 2121 to move the cartridge P
upward by a predetermined amount. However, at this time, the
cartridge P does not abut against the abutment portions 2112a and
2112b and the abutment portions 2122a and 2122b. This is for
preventing the cartridge P from being brought into contact with and
rubbing against the front plate 2110, the rear plate 2120, or the
intermediate transfer unit 240 placed above the cartridge P when
the cartridge P is then further inserted to move the LED unit 230
upward.
[0152] If an insertion distance of the cartridge P for moving the
LED unit 230 upward is relatively short, the cartridge P may ride
on the pull-up member 2111 and the push-up member 2121 so that the
cartridge P abuts against the abutment portions 2112a and 2112b and
the abutment portions 2122a and 2122b.
[0153] <Removal of Cartridge P from Main Body>
[0154] Next, drawing and removing the cartridge P from the main
body 200 will be described. As shown in FIG. 27, with the cartridge
P being completely inserted into the main body, an engaging portion
2107 of the cartridge P engages an engaging portion 2108 of the LED
unit push-up cam 2101. Thus, when the cartridge P is drawn in a
direction opposite to the F direction from the state shown in FIG.
27, the LED unit push-up cam 2101 is also moved in the direction
opposite to the F direction. At this time, the cam surface 2105
slides on the cam surface 2104 of the LED unit push-up cam 2101 to
move the LED unit 230 downward. Thus, the cartridge pressing member
235 is withdrawn from the fitting hole 2106 of the cartridge P, and
the LED head 232 is moved from the exposure position to the
retracted position. At the same time, the cartridge P is moved
downward by a predetermined amount and retracted from the image
forming position, and enters a state as shown in FIG. 25.
[0155] In this state, the engaging portion 2107 of the cartridge P
is disengaged from the engaging portion 2108 of the LED unit
push-up cam 2101. Thus, the cartridge P can be further drawn in the
direction opposite to the F direction. When the cartridge P is
further drawn in the direction opposite to the F direction, the
cartridge P is withdrawn from the pull-up member 2111 and the
push-up member 2121, moved downward by a predetermined amount, and
can be removed from the main body.
[0156] <Operation Force in Insertion of Cartridge P into Main
Body 200>
[0157] An operation force required for inserting the cartridge P
into the main body 200, positioning the cartridge P in the image
forming position, and positioning the LED head 232 in the exposure
position will be described.
[0158] FIG. 28A is a graph illustrating an operation force required
when the cartridge P presses the pull-up member 2111 and the
push-up member 2121 in insertion of the cartridge P. The operation
force increases between when the cartridge P presses the pull-up
member 2111 and the push-up members 2121 and when the cartridge P
pushes down and rides on the members. The operation force reaches a
peak (maximum value) when the pull-up spring 2116 extends to the
maximum and the push-up spring 2126 contracts to the minimum.
[0159] The operation force may be restated as a reaction force
applied to the cartridge P when the cartridge P presses the pull-up
member 2111 and the push-up member 2121 against the biasing forces
of the pull-up spring 2116 and the push-up spring 2126. FIG. 28B is
a graph illustrating an operation force when the cartridge P
presses the LED push-up cam 2101 in insertion of the cartridge P.
The operation force increases while the cam surface 2104 of the LED
push-up cam 2101 pressed and moved by the cartridge P is pushing up
the cam surface 2105 of the LED unit 230. The operation force
reaches a peak (maximum value) when the pressing spring 236 of the
LED unit 230 contracts to the minimum.
[0160] The operation force may be restated as a reaction force
applied to the cartridge P when the cartridge P presses the LED
unit push-up cam 2101 against the biasing force of the pressing
spring 236 of the LED unit 230.
[0161] As such, in insertion of the cartridge P, the operation
force reaches the peak when the pull-up member 2111 and the push-up
member 2121 are pressed and when the LED push-up cam 2101 is
pressed.
[0162] FIG. 28C is a graph illustrating an operation force in
insertion of the cartridge P. The operation force reaches [.alpha.]
while the cartridge P is pressing the pull-up member 2111 and the
push-up member 2121, and reaches [.beta.] while the cam surface
2104 of the LED push-up cam 2101 pressed and moved by the cartridge
P is pushing up the cam surface 2105 of the LED unit 230. As such,
in this embodiment, the timing when the cartridge P presses the
pull-up member 2111 and the push-up member 2121 is different from
the timing when the cartridge P presses the LED push-up cam 2101 in
insertion of the cartridge P. Thus, the timings of the peak of the
operation force in insertion of the cartridge are shifted (made
different).
[0163] Specifically, in this embodiment, the cartridge P is moved
upward by the predetermined amount, and then the LED unit 230 is
moved upward, and the cartridge P is moved upward in a plurality of
separate times to reach the image forming position. Thus, as
compared to a configuration in which the cartridge P is moved
upward once at the same timing as upward movement of the LED unit
230 and moved to the image forming position, the maximum value of
the operation force required in insertion of the cartridge can be
reduced to improve usability.
Embodiment 4
[0164] Next, Embodiment 4 will be described. In Embodiment 3, the
cartridge P is positioned in the image forming position in
conjunction with the insertion of the cartridge P, and the LED unit
230 is pushed upward. In contrast to this, in this embodiment, a
cartridge P is positioned in an image forming position in
conjunction with insertion of the cartridge P, an LED unit 230 is
moved in conjunction with a closing operation of an openable and
closable member 270 for inserting the cartridge P, and an LED head
232 is moved to an exposure position.
[0165] In the description of this embodiment, the same components
as in Embodiment 3 are denoted by the same reference numerals and
descriptions thereof will be omitted, and different points will be
described.
[0166] <Mounting of Cartridge P to Main Body>
[0167] A mounting operation when the cartridge P is mounted to an
image forming apparatus 200 in this embodiment will be
described.
[0168] FIG. 29 is a perspective view of the image forming apparatus
200 seen obliquely from the front. The image forming apparatus 200
includes an inner openable and closable member 272 openable and
closable with respect to a main body inside an openable and
closable member 270. The inner openable and closable member 272 is
opened/closed in conjunction with the openable and closable member
270, and the openable and closable member 270 and the inner
openable and closable member 272 are opened to open the opening
portion 271. In replacement of the cartridge P, the openable and
closable member 270 and the inner openable and closable member 272
are opened to open the opening portion 271. The opening portion 271
is opened to expose four cartridge guides 2100 arranged in parallel
in the main body.
[0169] The cartridge P is inserted along the cartridge guides 2100
into the main body 200 in an axial direction (F direction) of a
photosensitive drum 1. As in Embodiment 3, a pulled-up portion 2113
of the cartridge P abuts against a pull-up member 2111 to rotate
the pull-up member 2111 downward around a shaft 2118. At the same
time, a pushed-up portion 2123 of the cartridge P abuts against a
push-up member 2121 to rotate the push-up member 2121 downward
around a shaft 2128.
[0170] When the cartridge P is further inserted in the F direction,
as shown in FIG. 30, the pulled-up portion 2113 rides on the
pull-up surface 2114 of the pull-up member 2111. At the same time,
the pushed-up portion 2123 also rides on the push-up member 2121.
As such, the cartridge P presses and rides on the pull-up member
2111 and the push-up member 2121. Thus, the cartridge P is moved
upward by biasing forces of a pull-up spring 2116 of the pull-up
member 2111 and a push-up spring 2126 of the push-up member
2121.
[0171] Then, as shown in FIG. 30, positioned portions 213a and 213b
abut against abutment portion 2112a and 2112b of a front plate 2110
and abutment portions 2122a and 2122b of a rear plate 2120. Thus,
the position of the cartridge P is determined in a vertical
direction (Z direction) and a direction vertically perpendicular to
a cartridge insertion direction (F direction) (see FIG. 22).
[0172] At the same time, a part of the cartridge P abuts against
the rear plate 2120 in the cartridge insertion direction (F
direction) to determine the position of the cartridge P in the
cartridge insertion direction (F direction).
[0173] As described above, the cartridge P reaches and is
positioned in the image forming position.
[0174] The inner openable and closable member 272 includes a cam
pressing portion 2203 that abuts against and presses a pressed
surface 2202 of an LED unit push-up cam 2101. An engaging portion
2230 is provided at a tip of the cam pressing portion 2203.
[0175] FIGS. 32A and 32B illustrate a part of the image forming
apparatus 200 around the inner openable and closable member 272 and
the cartridge guide 2100 seen from above. When the openable and
closable member 270 is closed, as shown in FIG. 32A, an engaging
portion 2230 of the cam pressing portion 2203 of the inner openable
and closable member 272 engages an inner openable and closable
member engaging portion 2231 of the LED unit push-up cam 2101.
[0176] When the openable and closable member 270 is further closed,
as shown in FIG. 32B, the cam pressing portion 2203 abuts against
the pressed surface 2202 to move the LED unit push-up cam 2101 in
the F direction.
[0177] As described above, the LED unit push-up cam 2101 is moved
in the F direction, and thus as in the first embodiment, the LED
unit 230 is moved upward, and a cartridge push-up member 235 fits
in a fitting hole 2106 in the cartridge P. Thus, as shown in FIG.
31, an LED head 232 is positioned in the exposure position.
[0178] When the cartridge P is removed from the main body 200, the
openable and closable member 270 is opened to open the inner
openable and closable member 272. At this time, the LED unit
push-up cam 2101 including the inner openable and closable member
engaging portion 2231 that engages the engaging portion 2230 of the
cam pressing portion 2203 of the inner openable and closable member
272 is moved in the direction opposite to the F direction in
conjunction with the operation of opening the inner openable and
closable member 272. The LED unit 230 is moved downward to move the
LED head 232 from the exposure position to the retracted position
as in Embodiment 3. The cartridge P is drawn in the direction
opposite to the F direction in this state, and thus the cartridge P
can be removed from the main body 200.
[0179] <Operation Force in Mounting the Cartridge P to the Main
Body 200>
[0180] Next, an operation force required for inserting the
cartridge P into the main body 200 to close the openable and
closable member 270, positioning the cartridge P in the image
forming position, and positioning the LED head 232 in the exposure
position.
[0181] The operation force required in insertion of the cartridge P
reaches a peak between when the cartridge P presses the pull-up
member 2111 and the push-up member 2121 and when the cartridge P
pushes down and rides on the members. The operation force required
for closing the openable and closable member 270 reaches a peak
while the cam pressing portion 2203 is pressing the pressed surface
2202 to move the LED unit push-up cam 2101 in the F direction, and
the cam surface 2104 is pushing up the cam surface 2105 of the LED
unit 230.
[0182] Thus, in this embodiment, the cartridge P is moved upward to
the image forming position in conjunction with insertion of the
cartridge P, and then the LED unit 230 is moved upward in
conjunction with closing the openable and closable member 270 to
move the LED head 232 to the exposure position. Thus, as compared
to a configuration in which the cartridge P is moved upward once at
the same timing as upward movement of the LED unit 230 and
positioned in the image forming position, the maximum value of the
required operation force can be reduced. This reduces an operation
force required for mounting the cartridge P to improve
usability.
Embodiment 5
[0183] Next, Embodiment 5 will be described. This embodiment is
different from Embodiment 3 in that a guide member 251 that guides
insertion of a cartridge P can be drawn from a main body 200
according to mounting and removal of the cartridge P. In this
embodiment, a case where the guide member 251 is configured to be
drawable as a cartridge placement member on which the cartridge P
is placed is described.
[0184] In the description of this embodiment, the same components
as in Embodiment 3 are denoted by the same reference numerals and
descriptions thereof will be omitted, and different points will be
described.
[0185] <Drawing Configuration of Guide Member 251>
[0186] A drawing configuration of the guide member 251 will be
described. FIG. 33 is a sectional view of the cartridge P and
therearound in the image forming apparatus 200 of this embodiment
seen in an axial direction of a photosensitive drum 1. FIG. 34 is a
partial perspective view of the image forming apparatus 200 in a
state where the cartridge P is placed on the guide member 251 drawn
from the main body. An exterior portion of the image forming
apparatus 200 is not shown.
[0187] The guide member 251 is a thin plate member that is long in
a front/rear direction and protrudes upward, and is provided along
a rail 220a provided on an upper surface frame 220 corresponding to
a rail groove 251c so as to be movable in the axial direction of
the photosensitive drum 1. The guide member 251 includes a lateral
direction restriction wall (region that can abut against the
cartridge P) 258 that guides the cartridge P in the left and right
direction, and a vertical direction restriction wall 259 that
guides the cartridge P in a vertical direction. The vertical
direction restriction wall 259 is provided on both left and right
sides of the guide member 251 in the axial direction (longitudinal
direction of the guide member 251) of the photosensitive drum 1. On
the side of an opening portion 271 (front side) of the guide member
251, a grip 264 (FIG. 35) gripped by a user for drawing the guide
member 251 toward the opening portion 271 is provided.
[0188] The LED unit 230 is placed inside the guide member 251. The
LED unit 230 is held by an LED holding rail 251d formed inside the
guide member 251, and an LED holding casing 2154 secured to an
upper surface frame 220. The LED unit 230 is not drawn but is
secured and held in the main body 200 even if the guide member 251
is drawn.
[0189] FIG. 35 is a sectional view taken in the axial direction of
the photosensitive drum 1. In this embodiment, an LED unit push-up
mechanism 2150 including a push-up cam 2153 is provided as a
mechanism for vertically moving the LED unit 230 and moving an LED
head 232 between the retracted position and the exposure position.
Two LED unit push-up mechanisms 2150 are provided apart from each
other in the axial direction of the photosensitive drum 1.
[0190] The LED unit push-up mechanism 2150 will be described. Two
push-up cams 2153 are provided in one LED unit 230, one on an
upstream side and the other on a downstream side in the F
direction. The push-up cam 2153 is held rotatably in the arrow E
direction by a cam holding member 2151 secured to the upper surface
frame 220. A toggle spring 2152 extends between the push-up cam
2153 and the cam holding member 2151. One end of the toggle spring
2152 is supported by an extending portion 2151a of the cam holding
member 2151. The other end is supported by an extending portion
2153a provided below the push-up cam 2153. With such a
configuration, the push-up cam 2153 serves as a toggle
mechanism.
[0191] <Mounting of Cartridge P to Main Body>
[0192] Mounting of the cartridge P to the image forming apparatus
200 will be described. In mounting the cartridge, the guide member
251 corresponding to the cartridge P to be mounted is drawn toward
the opening portion 271 (front side). In this state, the cartridge
P is placed on the guide member 251 so that the guide member 251
enters a space between a cleaner unit 217 and a developing unit 214
of the cartridge P. In this state, the vertical direction
restriction wall 259 is brought into contact with a bottom surface
of the cartridge P.
[0193] With the guide member 251 being drawn toward the opening
portion 271, the guide member 251 is secured in a state of being
urged in a drawing direction from the main body 200 by a toggle
mechanism (not shown). Thus, even if the cartridge is inserted in
the F direction, the guide member 251 is held in a state of being
drawn toward the opening portion 271 against a friction force
between the cartridge P and the guide member 251, and only the
cartridge P slides on the guide member 251 and is moved in the F
direction. At this time, a slope portion 258a (FIG. 34) is
longitudinally formed on left and right sides of an upper portion
of the guide member 251 so as to facilitate insertion of the
cartridge P.
[0194] When the cartridge P is inserted so that an abutment surface
266 of the cartridge P abuts against an abutment surface 265 of the
guide member 251, the abutment surface 266 of the cartridge P
presses the abutment surface 265 of the guide member 251. This
releases urging of the guide member 251 of the toggle mechanism in
a drawing direction from the main body 200. Thus, the cartridge P
and the guide member 251 are then integrally inserted into the main
body in the F direction.
[0195] As shown in FIG. 36A, the pulled-up portion 2113 provided in
the cartridge P abuts against the pull-up member 2111. At the same
time, the pushed-up portion 2123 of the cartridge P abuts against
the push-up member 2121. As shown in FIG. 36B, when the cartridge P
is pressed in the F direction as in Embodiment 3, the cartridge P
rides on the pull-up member 2111 and the push-up member 2121 and is
moved in the Z direction by a predetermined amount. At this time,
as in Embodiment 3, the cartridge P has not abut against the
abutment portions 2112a and 2112b and the abutment portions 2122a
and 2122b. In this state, the cam 2153 is urged by the toggle
spring 2152 so as to be rotated in an arrow D direction.
[0196] In FIGS. 36A to 36D, the push-up member 2121 of the rear
plate 2120 is not shown. The push-up cam 2153 on the downstream
side in the F direction operates in the same manner as that on the
upstream side in the F direction, and thus illustration and
descriptions thereof will be omitted.
[0197] Further, when the cartridge P is inserted in the F
direction, as shown in FIG. 36B, the cam abutment surface 251a
provided on the guide member 251 abuts against the push-up cam
2153. The abutment surface 251a is moved with the movement of the
guide 251 in the F direction, the push-up cam 2153 is pressed, and
the push-up cam 2153 is rotated in the arrow C direction against
the biasing force of the toggle spring 2152. At this time, the cam
surface 2153b provided on the push-up cam 2153 presses a bottom
surface of the LED unit 230, and moves the LED unit 230 upward.
[0198] When the cartridge P is further inserted, as shown in FIG.
36C, the extending portion 2153a of the toggle spring 2152 reaches
a neutral position shown by the dash-single-dot line. When the
extending portion 2153a goes beyond the neutral position, the
toggle spring 2152 urges the push-up cam 2153 in the arrow C
direction, the push-up cam 2153 is further rotated in the arrow C
direction, and the LED unit 230 is further moved upward. As shown
in FIG. 36D, the cartridge P is pressed by the cartridge push-up
member 235 provided on the LED unit 230 and moved upward, and the
positioned portions 213a and 213b abut against the abutment
portions 2112a and 2112b of the front plate 2110, and the abutment
portions 2122a and 2122b of the rear plate 2120. Thus, the
cartridge P is positioned in the vertical direction (Z direction)
and the direction vertically perpendicular to the cartridge
insertion direction (F direction).
[0199] The guide member 251 pressed by the cartridge P abuts
against a stopper portion (not shown) provided on a side plate 2120
in the F direction to prevent the cartridge P and the guide member
251 from being further inserted and moved. At this time, the
push-up cam 2153 abuts against the LED unit 230 at a portion
vertically upward of a rotation center of the push-up cam 2153, and
is arranged in the vertical direction. Thus, the reaction force to
rotate the push-up cam 2153 is directed to the rotation center of
the push-up cam 2153 by self-weight or the like of the LED unit
230, and thus the push-up cam 2153 is not rotated and held in this
state.
[0200] At the same time, the cartridge pressing member 235 fits in
the fitting hole (not shown) in the cartridge P to position the LED
head 232 in the main scanning direction (F direction) and the sub
scan direction (direction perpendicular to the F and Z directions)
of the cartridge P. As such, the LED head 232 reaches the exposure
position and is positioned. The LED head 232 is positioned in the
exposure position, and thus the cartridge P reaches the image
forming position and is positioned.
[0201] A resultant force of pressing forces of the pull-up member
2111, the push-up member 2121 and the cartridge pressing member 235
of the LED unit 230 causes a sufficient pressing force to position
the cartridge P in the image forming position and transfer the
toner image to the intermediate transfer belt 241.
[0202] <Removal of Cartridge P from Main Body>
[0203] Drawing and removing the cartridge P from the main body 200
will be described. As shown in FIG. 36D, with the cartridge P being
mounted to the main body 200 and being in the image forming
position, the grip 264 is held to draw the guide member 251 in the
direction opposite to the F direction. Then, the cam abutment
surface 251b provided on the guide member 251 abuts against the
push-up cam 2153 to rotate the push-up cam 2153 in the arrow D
direction. At this time, the LED unit 230 is moved down along the
cam surface 2153b. Thus, the cartridge pressing member 235 is
withdrawn from the fitting hole in the cartridge P, and the LED
head 232 is moved from the exposure position to the retracted
position. At the same time, the cartridge P is also moved downward
by a predetermined amount and retracted from the image forming
position.
[0204] When the guide member 251 is further drawn, as shown in FIG.
36C, the extending portion 2153a of the toggle spring 2152 goes
beyond a neutral position of the toggle mechanism, and the push-up
cam 2153 is urged in the arrow D direction by the toggle spring
2152. Then, when the guide member 251 is drawn to the position
shown in FIG. 36B, rotation of the push-up cam 2153 is restricted
by a detent (not shown).
[0205] When the guide member 251 is further drawn, the abutment
surface 266 is pressed against the abutment surface 265 of the
guide member 251, the cartridge P drawn integrally with the guide
member 251 is disengaged from the pull-up member 2111 and the
push-up member 2121, and moved downward by a predetermined amount.
As such, the guide member 251 is drawn toward the opening portion
271 to draw the cartridge P, and thus the cartridge P can be
removed from the main body 200.
[0206] As such, in this embodiment, as in Embodiment 3, the timing
when the cartridge P presses the pull-up member 2111 and the
push-up member 2121 is different from the timing when the cartridge
P presses the push-up cam 2153 in insertion of the cartridge P.
Thus, the timings of the peak of the operation forces in insertion
of the cartridge are shifted.
[0207] Specifically, in this embodiment, the cartridge P is moved
upward by a predetermined amount, and then the LED unit 230 is
moved upward, and the cartridge P is moved upward in a plurality of
separate times to reach the image forming position. Thus, as
compared to a configuration in which the cartridge P is moved
upward once at the same timing as upward movement of the LED unit
230 and moved to the image forming position, the maximum value of
the operation force required in insertion of the cartridge can be
reduced to improve usability.
[0208] In this embodiment, with the guide member 251 being drawn
from the main body 200 toward the opening 271, the center of
gravity of the cartridge P is placed outside of the main body 200
in the longitudinal direction (axial direction of the
photosensitive drum 1) of the cartridge P.
[0209] Thus, the user can grip a portion corresponding to the
center of gravity of the cartridge P in the longitudinal direction
of the cartridge P. Thus, as compared to a case where the user
grips an end of the cartridge P in the longitudinal direction to
insert or remove the cartridge P into or from the main body 200,
the cartridge can be held and operated without application of the
moment of the center of gravity of the cartridge P for good
usability.
Other Embodiments
[0210] In Embodiments 4 and 5, the replacement of cartridge P
having a side-oriented configuration in which the cartridge P is
inserted into the axial direction of the photosensitive drum 1 and
thus mounted to or removed from the main body 200 has been
described. However, the cartridge P may be applied to a
configuration in which the cartridge P is drawn in a direction
different from an arrangement direction of the cartridge P and the
LED unit 230 and a direction perpendicular to the axial direction
of the photosensitive drum 1 (for example, Japanese Patent
Application Laid-Open No. 2009-128506).
[0211] Also in such a configuration, in mounting and removal of the
cartridge P, the cartridge P and the LED unit 230 are moved in the
arrangement direction of the cartridge P and the LED unit 230.
Thus, in this configuration, timing when the cartridge P is moved
in the arrangement direction of the cartridge P and the LED unit
230 is different from timing when the LED unit 230 is moved in the
arrangement direction of the cartridge P and the LED unit 230. Such
a configuration can reduce a maximum value of a required operation
force.
[0212] While the present invention has been described with
reference to exemplary embodiments, it is to be understood that the
invention is not limited to the disclosed exemplary embodiments.
The scope of the following claims is to be accorded the broadest
interpretation so as to encompass all such modifications and
equivalent structures and functions.
[0213] This application claims the benefit of Japanese Patent
Application No. 2010-126812, filed Jun. 2, 2010, Japanese Patent
Application No. 2011-114806, filed May 23, 2011 and Japanese Patent
Application No. 2011-091240, filed Apr. 15, 2011, which are hereby
incorporated by reference herein in their entirety.
* * * * *