Incremental printing of symbolic information – Ink jet – Controller
Reexamination Certificate
2002-02-14
2003-04-22
Nguyen, Lamson (Department: 2853)
Incremental printing of symbolic information
Ink jet
Controller
C347S014000, C347S035000, C347S036000
Reexamination Certificate
active
06550885
ABSTRACT:
TECHNICAL FIELD
The present invention relates to an ink jet recording apparatus provided with an ink jet recording head for use in forming images on recording paper by ejecting ink drops from nozzle orifices, and a flushing region disposed on a head moving path for receiving the ink drops ejected when a flushing driving signal is supplied to the recording head, and more particularly to an ink jet recording apparatus provided with an ink collecting unit for effectively collecting unnecessary mist (atomized ink) resulting from fine ink drops produced during the flushing operation.
The present invention relates to an ink jet recording apparatus provided with an ink collecting unit for effectively collecting unnecessary mist (atomized ink) resulting from ink drops produced at the time of inspecting an ink ejecting condition so as to detect any unoperating nozzle by checking the presence or absence of the ink drops ejected from nozzle orifices of a recording head.
The present invention relates to an ink jet recording apparatus in which at the time of inspecting an ink ejecting condition so as to detect any unoperating nozzle, it is ensured that such an unoperating nozzle can be detected and an inspecting method used in the apparatus.
DESCRIPTION OF RELATED ART
Ink jet recording apparatus are now widely used for printing including color printing partly because relatively less printing noise is produced and partly because high-density small dots are formable. The ink jet recording apparatus of this type is generally provided with an ink jet recording head mounted on a carriage and used for scanning recording paper in its width direction and a paper feeder for moving the recording paper in a direction perpendicular to the scanning direction of the recording head. Then recording is performed by ejecting ink drops from the recording head onto the recording paper according to printing data.
Further, not only text printing with black ink but also full-color printing can be performed by continuously supplying, to the recording head, black ink and three kinds of color ink of yellow, cyan and magenta, for example, by varying the ejection ratios of these different kinds of color ink.
In view of the fact that the ink jet recording apparatus like this is used for printing by ejecting the ink pressurized in a pressure generating chamber from nozzle orifices as ink drops onto recording paper, there may develop poor-quality printing due to a rise in ink viscosity originating from evaporation of an ink solvent from the nozzle orifices, solidification of ink, adhesion of dust, mixture of bubbles and so forth. For this problem of poor-quality printing, the ink jet recording apparatus is provided with a head cap for sealing the nozzle orifices of the recording head and a wiper for cleaning the nozzle forming face as occasion demands while printing is not performed.
The head cap serves as not solely a cover member for preventing the ink of the nozzle orifices of the recording head from being dried out while printing is suspended but also what receives negative pressure from a suction pump when the nozzle orifices are clogged so as to suck and discharge the ink from the nozzle orifices whereby to solve the problem of clogging due to the solidification of ink in the nozzle orifices and the problem of an unsatisfactory ejection of ink resulting from the introduction of bubbles into an ink channel.
The process of forcing the ink to be sucked and discharged so as to solve the problems of clogging of the recording head and of the introduction of bubbles into the ink channel is called a cleaning operation, which is performed, for example, in case where printing is performed again after a long suspension of the operation of the recording apparatus or in case where the user depresses, for example, a cleaning switch after recognizing the deterioration of printed image quality. The cleaning operation is accompanied with the operation of wiping the nozzle forming face of the recording head with the wiper formed of an elastic plate of rubber or the like after the ink is caused to be sucked and discharged from the recording head.
A function of causing ink drops to be ejected by applying a driving signal to the recording head is also retained, though the driving signal is irrelevant to printing, which is called a flushing operation. The flushing operation is performed periodically to recover irregular meniscuses produced in the vicinity of the nozzle orifices of the head through the wiping operation of the wiper and to prevent any nozzle orifice ejecting few ink drops from being clogged with extremely viscous ink while printing is performed.
FIG. 5
shows an example of a conventional ink jet recording apparatus so arranged that during the flushing operation, ink drops are ejected toward a flushing region formed on a head moving path.
In
FIG. 5
, reference numeral
1
denotes a carriage so arranged as to be guided by a guide shaft
4
supported by left and right frames
2
and
3
via a timing belt driven by a carriage motor (not shown) and reciprocated in the axial direction of the guide shaft
4
.
The carriage
1
is loaded with an ink jet recording head
5
directed downward, a detachable black ink cartridge
6
and a detachable color ink cartridge
7
for supplying ink to the recording head
5
being also mounted thereon. Under the recording head
5
lies a platen
8
that extends in the scanning direction of the recording head
5
so that recording paper
9
mounted on the platen
8
can be moved by a paper feeder (not shown) successively in a direction perpendicular to the scanning direction of the recording head
5
.
Reference numeral
10
denotes a head cap that is disposed in a non-printing region (home position). When the recording head
5
is placed just above the head cap
10
, it is moved upward so as to seal the nozzle forming face of the recording head
5
. A suction pump
11
for providing negative pressure to the internal space of the head cap
10
is also disposed under the head cap
10
.
As described above, the head cap
10
serves as not solely a cover member for preventing the nozzle orifices of the recording head
5
from being dried out during the suspension of operation of the recording apparatus but also a cleaner for causing ink to be sucked and discharged by making the negative pressure from the suction pump
11
act on the recording head
5
.
Further, a wiper
12
formed of an elastic plate of rubber or the like is disposed in the vicinity of the head cap
10
and the operation of wiping the nozzle forming face of the recording head
5
is performed thereby when the carriage
1
moves toward the head cap
10
.
On the other hand, a flushing region
13
is formed in the vicinity of the other end opposing to the head cap
10
via the central printing region, The flushing region
13
is formed of an aperture in such a manner as to pass through the platen
8
. Further, part of a waste-ink absorber
14
for absorbing the ink discharged via the pump
11
from the head cap
10
is disposed in the inner base portion of the aperture forming the flushing region
13
. The absorber
14
extends along the platen
8
and is contained in a casing member, that is, a waste-ink tank
15
.
In the recording apparatus, flushing is performed periodically as described above to prevent an unsatisfactory ejection of ink resulting from an increase in ink viscosity in an unused nozzle while printing is performed. Flushing is performed in each nozzle orifice with a frequency of about tens of shots every several seconds on average. The flushing operation may be performed with from thousands to tens of thousands shots from each nozzle periodically, depending on the timing after the cleaning operation for the prevention of mixture of colors is performed, the timing in the beginning of printing or while printing is performed.
When the aperture is formed in the platen
8
as the flushing region
13
of
FIG. 5
, the distance from the nozzle forming face of the recording head
5
up to the waste-ink absorber
14
is approx
Endo Hironori
Matsumoto Hitoshi
Nguyen Lamson
Seiko Epson Corporation
Stewart Charles W.
LandOfFree
Ink jet recording device and ink drop jetting inspection... 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 device and ink drop jetting inspection..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Ink jet recording device and ink drop jetting inspection... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3082388