Information
-
Patent Grant
-
6834170
-
Patent Number
6,834,170
-
Date Filed
Friday, January 3, 200321 years ago
-
Date Issued
Tuesday, December 21, 200419 years ago
-
Inventors
-
Original Assignees
-
Examiners
Agents
-
CPC
-
US Classifications
Field of Search
US
- 399 103
- 399 105
- 399 119
-
International Classifications
-
Abstract
A developing apparatus includes sealing members which are installed on both inside walls of a housing and closely contact the housing, a developer roller, and a blade to prevent the toner contained in the housing from leaking out. Each sealing member includes a first sealing member and a second sealing member. The first sealing member has a side part that elastically and closely contacts one inside wall of the housing and a short side part of the blade, and a front part that elastically and closely contacts the outer circumference of the developer roller. The second sealing member overlaps with the first sealing member and has a front part that elastically and closely contacts an inside surface of the blade and the outer circumference of the developer roller. Therefore, deterioration of a close contact of the sealing members due to compression and deformation of the sealing members may be prevented. Accordingly, a developing apparatus is configured to prevent leakage of toner.
Description
CROSS-REFERENCE TO RELATED APPLICATION
This application claims the benefit of Korean Application No. 2002-29952, filed May 29, 2002, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a developing apparatus of a dry electrophotographic image forming apparatus, and more particularly, to a developing apparatus having a sealing member to prevent leakage of dry toner (hereinafter referred to as toner) contained in the developing apparatus.
2. Description of the Related Art
In general, a dry electrophotographic image forming apparatus contains toner and supplies the toner to a photoreceptor medium, such as a photoreceptor drum or the like, to develop a latent electrostatic image on the photoreceptor medium. Here, the toner is minute powder having a predetermined color and has to be contained in the developing apparatus except when being adhered to the latent electrostatic image. Therefore, the developing apparatus of the dry electrophotographic image forming apparatus using toner generally has a sealing member to prevent leakage of the toner.
FIG. 1
is an exploded perspective view of a conventional developing apparatus having sealing members. As shown in
FIG. 1
, the conventional developing apparatus includes a housing
100
which contains toner, and a blade
130
and a developer roller
120
which are respectively combined with the housing
100
. The conventional developing apparatus also includes sealing members
140
which are disposed on insides
102
of right and left walls
104
of the housing
100
and closely contact the blade
130
and the developer roller
120
to prevent the toner in the housing
100
from leaking.
The developer roller
120
is coupled to couplings
101
which are prepared in the right and left walls
104
of the housing
100
, to rotate. The developer roller adheres the toner in the housing
100
onto an outer circumference thereof, and supplies the toner to a photoreceptor drum (not shown) to develop a latent electrostatic image on the photoreceptor drum.
The blade
130
is conjoined with an upper surface
103
of the housing
100
in order to longitudinally contact the outer circumference of the developer roller
120
. Thus, the blade
130
rubs against the outer circumference of the developer roller
120
that is rotating to scrape away the toner excessively adhered onto the outer circumference of the developer roller
120
so as to form a toner layer having a predetermined thickness.
Here, a length L
2
of the developer roller
120
is smaller than an inner distance L
1
between the right and left walls
104
of the housing
100
, and a length L
3
of the bladed
130
is smaller than the length L
2
of the developer roller
120
. Thus, the toner may leak through gaps between right and left ends
121
of the developer roller
120
and the insides
102
of the right and left walls
104
of the housing
100
, and gaps between the blade
130
and the insides
102
of the right and left walls
104
of the housing
100
. Therefore, in order to prevent leakage of the toner, the sealing members
140
are disposed on the insides
102
of the right and left walls
104
of the housing
100
.
Since the sealing members
140
are generally formed of a sponge material, the sealing members
140
elastically and closely contact the outer circumference of the developer roller
120
, the blade
130
, and the insides
102
of the right and left walls
104
of the housing
100
.
According to the above-described structure, when the sealing members
140
, the blade
130
, and the developer roller
120
are sequentially combined with the housing
100
, the sealing members
140
closely contact the insides
102
of the right and left walls
104
of the housing
100
, the outer circumference of the developer roller
120
, and the blade
130
. Thus, gaps between the right and left ends
121
of the developer roller
120
and the insides
102
of the right and left walls
104
of the housing
100
, and gaps between the blade
130
and the insides
102
of the right and left walls
104
of the housing
100
are blocked to prevent leakage of the toner.
As described above, the length L
2
of the developer roller
120
is smaller than the inner distance L
1
between the right and left walls
104
of the housing
100
, and the length L
3
of the blade
130
is smaller than the length L
2
of the developer roller
120
. Thus, a contact width T
2
between the blade
130
and the sealing member
140
is smaller than a width T
1
of the sealing member
140
.
FIG. 2A
is a partial perspective view of the assembled conventional developing apparatus of
FIG. 1
, and
FIG. 2
is an enlarged view of portion C of FIG.
2
A.
FIG. 3A
is a cross-sectional view along cutting plane line A-A′ of
FIG. 2A
, and
FIG. 3B
is an enlarged view of portion D of FIG.
3
A.
As shown in
FIGS. 2A
,
2
B,
3
A, and
3
B, lower portions of a front part
141
(shown in
FIG. 1
) of the sealing members
140
closely contact the outer circumference of the developer roller
120
, and upper portions of the front part
141
of the sealing members
140
closely contact an inside surface
131
(shown in
FIG. 1
) of the blade
130
by the contact width T
2
.
A lower long side part
133
of the blade
130
has a bent portion
134
, perpendicular to the long side part
133
, in order to prevent the outer circumference of the developer roller
120
from being damaged due to contact with the blade
130
. Since the bent portion
134
raises the sealing member
140
, the sealing member
140
does not contact the outer circumference of the developer roller
120
at a portion in which the bent portion
134
is formed, thereby forming a gap
160
. Reference character “a” of
FIG. 2B
represents a portion of the sealing member
140
which does not contact the blade
130
, but is pulled and deformed in a direction
145
due to a portion of the sealing member
140
that contacts the blade
130
to be compressed, thereby forming a gap
150
between the sealing member
140
and the outer circumference of the developer roller
120
. As a result of the above, the toner in the housing
100
may leak through gaps
160
and
150
.
SUMMARY OF THE INVENTION
Accordingly, it is an aspect of the present invention to provide a developing apparatus having a sealing member which prevents deterioration of the sealing member due to compression and deformation of the sealing member.
Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.
The foregoing and/or other aspects of the present invention are achieved by providing a developing apparatus including a housing, a developer roller, a blade, and sealing members. The housing contains toner. The developer roller is combined with the housing to rotate and adheres the toner onto an outer circumference thereof to supply the toner out of the housing. The blade controls an amount of toner that is adhered onto the outer circumference of the developer roller. The sealing members are installed on both inside walls of the housing and closely contact the housing, the developer roller, and the blade to prevent the toner from leaking out. The sealing members include a first sealing member and a second sealing member. The first sealing member has a side part that elastically and closely contacts the inside walls of the housing and a short side part of the blade, and a front part that elastically and closely contacts the outer circumference of the developer roller. The second sealing member overlaps with the first sealing member and has a front part that elastically and closely contacts an inside surface of the blade and the outer circumference of the developer roller.
According to an aspect of the invention, the second sealing member further includes a horizontal slit which is cut along a contact line with a lower long side part of the blade. The horizontal slit is cut at least to a depth in which the second sealing member is compressed when the blade is combined with the housing. The second sealing member overlaps with and is attached to the first sealing member.
According to an aspect of the invention, the developing apparatus includes the sealing member having a side part, a front part, and a vertical slit. The side part closely contacts the inside walls of the housing. The front part has an upper portion that partially overlaps with and elastically and closely contacts an inside surface of the blade, and a lower portion that elastically and closely contacts the outer circumference of the developer roller. The vertical slit is cut along a short side part of the blade at least up to a lower long side part of the blade.
According to an aspect of the invention, the sealing member further includes a horizontal slit which is cut along a contact line with the lower long side part of the blade to the short side part of the blade.
According to an aspect of the invention, the vertical slit is cut at least to a depth in which the sealing member is compressed when the blade is combined with the housing.
According to another aspect of the invention, the horizontal slit is cut at least to a depth in which the sealing member is compressed when the blade is combined with the housing.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and/or other aspects and advantages of the invention will become apparent and more appreciated from the following description of the preferred embodiments, taken in conjunction with the accompanying drawings of which:
FIG. 1
is an exploded perspective view of a conventional developing apparatus having sealing members;
FIG. 2A
is a partial perspective view of the assembled conventional developing apparatus of
FIG. 1
;
FIG. 2B
is an enlarged view of portion C of
FIG. 2A
;
FIG. 3A
is a cross-sectional view along cutting plane line A-A′ of
FIG. 2A
;
FIG. 3B
is an enlarged view of portion D of
FIG. 3A
;
FIG. 4
is an exploded perspective view of a developing apparatus having sealing members, according to an embodiment of the present invention;
FIG. 5A
is a partial perspective view of the assembled developing apparatus of
FIG. 4
;
FIG. 5B
is an enlarged view of portion E of
FIG. 5A
;
FIG. 6A
is a cross-sectional view along cutting plane line B-B′ of
FIG. 5A
;
FIG. 6B
is an enlarged view of portion F of
FIG. 6A
;
FIG. 7
is a perspective view of a sealing member, according to another embodiment of the present invention;
FIG. 8A
is a cross-sectional view showing a sealed state of a developing apparatus, according to the present invention, using the sealing member shown in
FIG. 7
;
FIG. 8B
is an enlarged view of portion G of
FIG. 8A
;
FIG. 9
is a perspective view of a sealing member, according to another embodiment of the present invention; and
FIG. 10
is a perspective view of a sealing member, according to another embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
Reference will now be made in detail to the present preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to like elements throughout.
FIG. 4
is an exploded perspective view of a developing apparatus having sealing members, according to an embodiment of the present invention. As shown in
FIG. 4
, the developing apparatus includes a housing
400
, a developer roller
420
, a blade
430
, and first and second sealing members
440
and
450
.
First, the respective first and second sealing members
440
and
450
are overlapped and then are symmetrically combined with insides
402
of right and left walls
404
of the housing
400
that contain toner. Sides of the first sealing members
440
closely contact the insides
402
of the right and left walls
404
of the housing
400
, respectively. Front parts
441
of the first sealing members
440
are elastically compressed and closely contact an outer circumference of the developer roller
420
when the developer roller
420
is combined with the housing
400
. Front parts
451
of the second sealing members
450
are elastically compressed and closely contact the outer circumference of the developer roller
420
and an inside surface
431
of the blade
430
when the developer roller
420
and the blade
430
are combined with the housing
400
.
A thickness T
3
of the first sealing members
440
is predetermined so that an inner distance L
4
between the first sealing members
440
that are disposed on right and left sides of the housing, is equal to or slightly smaller than a length L
3
of the blade
430
. A thickness T
4
of the second sealing members
450
is predetermined so that an inner distance L
5
between the second sealing members
450
that are disposed on right and left sides of the housing, is slightly greater than an effective image width L
6
. Here, the effective image width L
6
represents a width of an image which is formed in an image forming apparatus (not shown).
The first and second sealing members
440
and
450
are preferably formed of an elastically deformable material (for example, a sponge).
Further, the blade
430
is combined with the housing
400
. The blade
430
, which scrapes away the toner excessively adhered onto the outer circumference of the developer roller
420
so as to form a toner layer having a predetermined thickness, applies a predetermined pressure to the outer circumference of the developer roller
420
to elastically and closely contact the outer circumference of the developer roller
420
. Since the inner distance L
4
between the first sealing members
440
is equal to or slightly smaller than the length L
3
of the blade
430
, right and left short side parts
432
of the blade
430
elastically and closely contact inner surfaces of the first sealing members
440
.
The inner surface
431
of the blade
430
contacts the front parts
451
of the second sealing members
450
by the thickness T
4
of the second sealing members
450
. Here, when the second sealing members
450
are elastically compressed, the inner surface
431
of the blade
430
closely contacts the front parts
451
of the second sealing members
450
.
The developer roller
420
is combined with couplings
401
which are disposed in the right and left sides of the housing
400
. Here, the front parts
441
and
451
of the first and second sealing members
440
and
450
are elastically compressed and closely contact the outer circumference of the developer roller
420
. Also, a lower long side part
433
of the blade
430
elastically contacts the outer circumference of the developer roller
420
.
FIG. 5A
is a partial perspective view of the assembled developing apparatus of
FIG. 4
, and
FIG. 5B
is an enlarged view of portion E of FIG.
5
A.
FIG. 6A
is a cross-sectional view along cutting plane line B-B′ of
FIG. 5A
, and
FIG. 6B
is an enlarged view of portion F of FIG.
6
A.
Referring to
FIGS. 5A
,
5
B,
6
A, and
6
B, a lower portion of the front part
441
(show in
FIG. 4
) of the first sealing member
440
is pushed and compressed by the outer circumference of the developer roller
420
, to elastically and closely contact the outer circumference of the developer roller
420
. Upper and lower portions of the front part
451
(shown in
FIG. 4
) of the second sealing member
450
are compressed by the blade
430
and the outer circumference of the developer roller
420
, respectively, to elastically and closely contact the blade
430
and the outer circumference of the developer roller
420
.
Here, the lower long side part
433
of the blade
430
has a bent portion
434
which does not allow the second sealing member
450
to closely contact the developer roller
420
. As a result, a gap
460
may be formed between the second sealing member
450
and the developer roller
420
.
However, the first sealing member
440
closely contacts the second sealing member
450
, and as represented by reference character “b” of
FIG. 5
, the first sealing member
440
contacts the short side part
432
(shown in
FIG. 4
) of the blade
430
. Thus, the toner does not leak out of the housing
400
, except for toner which is supplied to a photoreceptor drum (not shown) via a contact portion between the outer circumference of the developer roller
420
and the blade
430
.
FIG. 7
is a perspective view of a sealing member, according to an embodiment of the present invention.
FIG. 8A
is a cross-sectional view showing a sealed state of a developing apparatus, according to the present invention, using the sealing member shown in FIG.
7
.
FIG. 8B
is an enlarged view of portion G of FIG.
8
A.
Referring to
FIGS. 7
,
8
A, and
8
B, a second sealing member
500
has a horizontal slit
480
cut along a contact line between the developer roller
420
and the lower long side part
433
of the blade
430
.
In the above-described structure according to the embodiment as shown in
FIG. 7
, a front part
501
of the second sealing member
500
may be divided into upper and lower portions. Thus, since the bent portion
434
of the lower long side part
433
of the blade
430
is inserted into the horizontal slit
480
, a gap
490
, which is formed between the second sealing member
500
and the outer circumference of the developer roller
420
, may be removed or minimized. The horizontal slit
480
is cut at least to a depth D
1
in which the second sealing member
500
is compressed when the blade
430
is combined with the housing
400
. Here, the first and second sealing members
440
and
500
may be attached to overlap each other, and then combined with the housing
400
.
FIG. 9
is a perspective view of a sealing member, according to another embodiment of the present invention. Referring to
FIG. 9
, sealing members
600
, which may perform the same functions as those of both the first and second sealing members
440
and
450
, are symmetrically combined with the insides
402
of the right and left walls
404
of the housing
400
containing the toner. One side of the sealing members
600
closely contacts the inside
402
of the sidewall
404
of the housing
400
. An upper portion of a front part
920
partially overlaps with and elastically and closely contacts the inside surface
431
of the blade
430
. A lower portion of the front part
920
elastically and closely contacts the outer circumference of the developer roller
420
. Also, the sealing member
600
has a vertical slit
910
cut along the short side part
432
of the blade
430
at least up to the lower long side part
433
of the blade
430
.
Here, it is preferable that a thickness T
5
of the sealing member
600
is equal to a value obtained by adding the thickness T
3
of the first sealing member
440
(shown in
FIG. 4
) and the thickness T
4
of the second sealing member
450
(shown in FIG.
4
). Thus, the sealing member
600
and the blade
430
overlap each other by the thickness T
4
of the second sealing member
450
.
It is also preferable that the vertical slit
910
is cut at least to a depth D
1
in which the front part
920
of the sealing member
600
is compressed when the blade
430
is combined with the housing
400
.
In the above-described structure according to the embodiment as shown in
FIG. 9
, when the sealing member
600
, the blade
430
, and the developer roller
420
are combined with the housing
100
, the sealing member
600
elastically and closely contacts the outer circumference of the developer roller
420
and the blade
430
. Here, as described with reference to
FIGS. 6A and 6B
, due to the bent portion
434
of the long side part
433
of the blade
430
, the sealing member
600
does not closely contact the developer roller
420
to thereby form a gap therebetween. However, since the sealing member
600
has the vertical slit
910
, the short side part
432
of the blade
430
closely contacts a side
930
which is formed due to the vertical slit
910
. As a result, the toner does not leak out of the housing
400
. In other words, by forming the vertical slit
910
in the single sealing member
600
, as described with reference to
FIGS. 5A and 6A
, the sealing member
600
produces the same effect as that of including the first and second sealing members
440
and
450
.
FIG. 10
is a perspective view of a sealing member, according to another embodiment of the present invention. As shown in
FIG. 10
, a sealing member
700
is the same as the sealing member
600
shown in
FIG. 9
except that it further has a horizontal slit
950
which is cut along the contact line with the lower long side part
433
of the blade
430
up to the short side part
432
of the blade
430
. It is preferable that the horizontal slit
950
is cut at least to the same depth D
1
as the vertical slit
910
. Accordingly, the single sealing member
700
produces the same effect as described with reference to
FIGS. 8A and 8B
.
As described above, in a developing apparatus according to the present invention, a close contact property among a sealing member, a developer roller, and a blade may be improved in order to minimize a gap formed around a contact line between the blade and the developer roller, and to prevent toner from leaking through the gap.
Although a few preferred embodiments of the present invention have been shown and described, it would be appreciated by those skilled in the art that changes may be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the claims and their equivalents.
Claims
- 1. A developing apparatus, comprising:a housing which contains toner; a developer roller which is combined with the housing to rotate and adheres toner onto an outer circumference thereof, to supply toner out of the housing; a blade which controls an amount of toner that is adhered onto the outer circumference of the developer roller; and sealing members which are installed on both inside walls of the housing and closely contact the housing, the developer roller, and the blade to prevent the toner from leaking out, wherein the sealing members comprise: a first sealing member which has a side part that elastically and closely contacts the inside walls of the housing and a short side part of the blade, and a front part that elastically and closely contacts the outer circumference of the developer roller; and a second sealing member which overlaps with the first sealing member and has a front part that elastically and closely contacts an inside surface of the blade and the outer circumference of the developer roller.
- 2. The developing apparatus of claim 1, wherein the second sealing member further comprises:a horizontal slit which is cut along a contact line with a lower long side part of the blade.
- 3. The developing apparatus of claim 2, wherein the horizontal slit is cut at least to a depth in which the second sealing member is compressed when the blade is combined with the housing.
- 4. The developing apparatus of claim 2, wherein the second sealing member overlaps with and is attached to the first sealing member.
- 5. The developing apparatus of claim 1, wherein a thickness of the first sealing member is predetermined so that an inner distance between the first sealing member disposed on the inside walls of the housing is equal to or slightly smaller than a length of the blade.
- 6. The developing apparatus of claim 1, wherein a thickness of the second sealing member is predetermined so that an inner distance between the second sealing member disposed on the inside walls of the housing is slightly greater than an image width to be formed by the developer roller.
- 7. The developing apparatus of claim 1, wherein the first and second sealing members are formed of an elastically deformable material.
- 8. A developing apparatus, comprising:a housing which contains toner; a developer roller which is combined with the housing to rotate and adheres toner onto an outer circumference thereof, to supply toner out of the housing; a blade which controls an amount of the toner that is adhered onto the outer circumference of the developer roller; and a sealing member which is installed on both inside walls of the housing and closely contacts the housing, the developer roller, and the blade to prevent the toner from leaking out, wherein the sealing member comprises: a side part which closely contacts the inside walls of the housing; a front part which has an upper portion that partially overlaps with and elastically and closely contacts an inside surface of the blade, and a lower portion that elastically and closely contacts the outer circumference of the developer roller; and a vertical slit which is cut along a short side part of the blade at least up to a lower long side part of the blade.
- 9. The developing apparatus of claim 8, wherein the vertical slit is cut at least to a depth in which the sealing member is compressed when the blade is combined with the housing.
- 10. The developing apparatus of claim 8, wherein the sealing member further comprises:a horizontal slit which is cut along a contact line with the lower long side part of the blade to the short side part of the blade.
- 11. The developing apparatus of claim 10, wherein the horizontal slit is cut at least to a depth in which the sealing member is compressed when the blade is combined with the housing.
- 12. The developing apparatus of claim 11, wherein the horizontal slit and the vertical slit are perpendicular to each other.
- 13. The developing apparatus of claim 11, wherein the horizontal slit is cut to at least a depth the same as the depth of the vertical slit.
- 14. A developing apparatus having a housing which contains toner, a developer roller combined with the housing to rotate and adhere toner onto an outer circumference thereof, and a blade to control an amount of adhered toner, the developing apparatus comprising:first and second sealing members which are installed on both inside walls of the housing and closely contact the housing, the developer roller, and the blade to prevent the toner from leaking out, wherein the first sealing members each include a side part that elastically and closely contacts the inside walls of the housing and a short side part of the blade, and a front part that elastically and closely contacts the outer circumference of the developer roller, and the second sealing members overlap with the respective first sealing members, each including a front part that elastically and closely contacts an inside surface of the blade and the outer circumference of the developer roller, and including a slit which is cut along a contact line with a long side part of the blade.
- 15. A developing apparatus having a housing which contains toner, a developer roller combined with the housing to rotate and adhere toner onto an outer circumference thereof, and a blade to control an amount of adhered toner, the developing apparatus comprising:a sealing member which is installed on both inside walls of the housing and closely contact the housing, the developer roller, and the blade to prevent the toner from leaking out, the sealing member including, a side part which closely contacts the inside walls of the housing, a front part which has a portion that partially overlaps with and elastically and closely contacts an inside surface of the blade, and a portion that elastically and closely contacts the outer circumference of the developer roller, and a slit which is cut along a short side part of the blade at least up to a long side part of the blade.
- 16. A developing apparatus having a housing which contains toner, a developer roller combined with the housing to rotate and adhere toner onto an outer circumference thereof, and a blade to control an amount of adhered toner, the developing apparatus comprising:a sealing member which is installed on both inside walls of the housing and closely contact the housing, the developer roller, and the blade to prevent the toner from leaking out, the sealing member including, a side part which closely contacts the inside walls of the housing, a front part which has a portion that partially overlaps with and elastically and closely contacts an inside surface of the blade, and a portion that elastically and closely contacts the outer circumference of the developer roller, a first slit which is cut along a short side part of the blade at least up to a long side part of the blade, and a second slit which is cut along a contact line with the long side part of the blade to the short side part of the blade.
- 17. The developing apparatus of claim 16, wherein the first slit and the second slit are perpendicular to each other.
- 18. The developing apparatus of claim 16, wherein the first slit is cut to at least a depth the same as the depth of the second slit.
Priority Claims (1)
Number |
Date |
Country |
Kind |
2002-29952 |
May 2002 |
KR |
|
US Referenced Citations (3)
Foreign Referenced Citations (3)
Number |
Date |
Country |
06308819 |
Nov 1994 |
JP |
2000-181223 |
Jun 2000 |
JP |
2000181223 |
Jun 2000 |
JP |