Incremental printing of symbolic information – Ink jet – Ejector mechanism
Reexamination Certificate
1999-01-22
2001-08-07
Barlow, John (Department: 2853)
Incremental printing of symbolic information
Ink jet
Ejector mechanism
C347S022000, C347S033000, C347S044000, C347S045000, C347S047000
Reexamination Certificate
active
06270191
ABSTRACT:
FIELD OF THE INVENTION
The present invention relates to an ink-jet recording head for jetting ink pressurized in a pressure generating chamber by pressurizing means from a nozzle aperture as an ink droplet, and in more detail, relates to an ink-jet recording head in which a nozzle aperture can be prevented from being clogged by a wiping member.
DESCRIPTION OF THE RELATED ART
An ink-jet recording head is provided with a nozzle plate wherein nozzle apertures are made at a predetermined pitch in a thin plate, a pressure generating chamber communicating with each nozzle aperture and a reservoir for supplying ink to a pressure generating chamber as is well-known, and is constituted so that an ink droplet is jetted from a nozzle aperture by pressurizing ink in a pressure generating chamber by a piezoelectric vibrator, a heater element and others.
As dust on recording paper and the leavings of ink adhere to a nozzle aperture and the vicinity and the nozzle aperture is often clogged because an ink-jet recording head executes printing at an interval to the extent that the ink-jet recording head almost comes in contact with recording paper and ink including a solid component such as dye is used, a nozzle plate is wiped by a blade of a rubber plate every predetermined time to remove dust on recording paper and the leavings of ink.
In the meantime, as described above, as an interval between a nozzle plate and recording paper is extremely small, the recording paper comes in contact with a nozzle aperture and an ink-repellent layer provided around the nozzle aperture may be worn.
Therefore, as shown in
FIG. 21A
, a measure to prevent recording paper from coming in contact with a protective layer in the vicinity of each nozzle aperture N by forming the protective layer composed of a metallic layer 1 to 30 &mgr;m thick in an area apart by approximately 100 to 150 &mgr;m from each nozzle aperture N of a nozzle plate P so that a concave portion C is formed around each nozzle aperture N is taken.
As the width of a concave portion C between adjacent nozzle apertures in the same column is extremely small to form an independent concave portion C every nozzle aperture as described above in recent cases, a pitch at which the nozzle apertures are arranged is 180 dpi per column and extremely small to thus enhance printing quality, it is very difficult to form such a concave portion. Therefore, as shown in
FIG. 21B
, a rectangular common concave portion C′ is formed around nozzle apertures N in one column.
A recording head H provided with the nozzle plate P constituted as described above is relatively moved in the direction D or D′ of a blade B (cleaning means) as shown as II and II′ after the blade B is lifted on the side of the recording head H with the recording head located on the upstream side of the blade B arranged on a path of movement as shown in
FIG. 22
(I). The blade B is elastically touched to the recording head H as shown as III and III′ and hereby, cleaning is executed.
At this time, as the most area of the blade B is dropped in the-concave portion C′, comes in contact with and rubs an ink-repellent layer F with strong pressure, there is a problem that the ink-repellent layer F is worn, scratched leavings K of ink are accumulated particularly along a wall W
2
on the downstream side out of walls W
1
and W
2
partitioning the concave portion C′ as shown in
FIGS. 23A and 23B
, and the recording paper is dirtied, a direction in which an ink droplet is jetted varies, or the like.
SUMMARY OF THE INVENTION
An ink-jet recording head according to the present invention comprises plural pressure generating chambers arranged at a predetermined pitch linearly in one or more columns for pressurizing ink by pressurizing means and a nozzle plate in which plural nozzle apertures each of which communicates with each pressure generating chamber are formed, and a protective layer for regulating so that a part of a blade comes in contact with a nozzle aperture when the blade is pressed on the nozzle plate is formed in the vicinity of the above nozzle aperture in a state in which an open exhaust port is secured on the side of the end of the protective layer in a direction in which the blade for cleaning is moved.
Therefore, a first object of the present invention is to provide an ink-jet recording head wherein ink which adheres to the nozzle plate, the leavings of ink and dust on paper can be securely exhausted in an area which has no effect upon jetting an ink droplet without wearing an ink-repellent layer and further, the ink-repellent layer can be prevented from being worn or broken by contact between the ink-repellent layer and recording paper.
A second object of the present invention is to provide an ink-jet recording apparatus provided with cleaning means suitable for the above recording head.
REFERENCES:
patent: 4479135 (1984-10-01), Kohashi
patent: 0383019 A2 (1990-08-01), None
patent: 0 631 869 A1 (1995-01-01), None
patent: 01 195048 (1988-01-01), None
patent: 63-095951 (1988-04-01), None
patent: 401195048 (1989-08-01), None
patent: 1-275047 (1989-11-01), None
patent: 4-169238 (1992-06-01), None
patent: 405084930 (1993-04-01), None
patent: 5-338160 (1993-12-01), None
patent: 8-025630 (1996-01-01), None
International Search Report.
Kitahara Tsuyoshi
Morikoshi Koji
Barlow John
Do An H.
Seiko Epson Corporation
Sughrue Mion Zinn Macpeak & Seas, PLLC
LandOfFree
Ink jet recording head and ink jet recorder does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Ink jet recording head and ink jet recorder, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Ink jet recording head and ink jet recorder will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2530222