Incremental printing of symbolic information – Ink jet – Ejector mechanism
Reexamination Certificate
1998-01-20
2001-03-27
Barlow, John (Department: 2853)
Incremental printing of symbolic information
Ink jet
Ejector mechanism
C347S036000
Reexamination Certificate
active
06206500
ABSTRACT:
BACKGROUND OF THE INVENTION
The present invention relates generally to printers, and, in particular, to improvements in an automatic-paper-feeder portion of a printer having an automatic paper feeder incorporated therein.
Further, the present invention relates to improvements in a driving mechanism for individually feeding sheets of paper.
Still further, the present invention relates to improvements in ink jet printers, and specifically to improvements in the construction and arrangement of the print area thereof, to improvements in the construction of the mounting the ink cartridge on the carriage thereof, and to improvements for reducing the width of ink jet printers in the direction of a row.
Further, the present invention relates generally to a method of discharging paper in an ink jet printer, and, in particular, to an improved technique of the discharging paper in which the discharged paper is neither damaged nor smeared.
FIG. 56
depicts a conventional printer described in Japanese Utility Model Unexamined Publication No. 272952/1991. An automatic paper feeder is constructed and arranged having a paper feed cassette
2002
, which is a paper stacker, detachably mounted in a printer body
2001
so a dead space DS is formed between the bottom of paper feed cassette
2002
and the bottom of body
2001
.
FIGS. 57-59
depict a second conventional printer described in Japanese Patent Utility Model Publication No. 74825/1988 having a stacker section
2004
on which paper P is stacked, incorporated in a printer case
2003
constructed and arranged so a dead space DS is formed between the bottom of printer case
2003
and stacker section
2004
.
As illustrated above, it is difficult to make the printers compact because of the dead space within the printer casings.
In the conventional printer construction of
FIGS. 57-59
, the stacker section is arranged as follows. If a paper discharge support
2101
rotates in a counterclockwise direction as viewed in
FIGS. 58 and 59
, an operating arm
2102
rotates therewith causing an intermediate lever
2103
to rotate in the clockwise direction as viewed in
FIGS. 58 and 59
. An engaging lever
2104
is rotated in said counterclockwise direction by the rotation of intermediate lever
2103
, and a pressure-plate operating lever
2106
rotates in the same direction as engaging lever
2104
since they are both mounted for rotation with lever shaft
2105
. A pressure plate member
2107
moves downward as viewed in
FIG. 57
by the rotation of pressure-plate operating lever
2106
to allow paper P to be inserted between pressure plate member
2107
and a separation pawl
2108
, thereby making it possible to accommodate paper P in a feeding holder
2109
.
However, in such a conventional printer, if paper discharge support
2101
rotates in the counterclockwise direction, pressure plate member
2107
moves downward, but separation pawl
2108
does not move. Therefore, if a plurality of sheets of paper are inserted, the edges of the top sheets may enter above separation pawl
2108
. Hence, this printer construction has a problem with the feeding-in operation.
In the above construction, intermediate lever
2103
and engaging lever
2104
are necessary, resulting in a complicated printer construction.
FIG. 60
depicts a mechanism for driving a paper feed-in roller in a conventional printer described in Japanese Utility Model Unexamined Publication No. 184174/1989. In
FIG. 60
, a transmission arm
2502
is supported on an apparatus body and can rotate about a fulcrum
2501
. A drive gear
2503
is axially supported on fulcrum
2501
. Further, a transmission gear
2505
for transmitting rotation from drive gear
2503
to a roller gear
2504
is axially supported at one side of transmission arm
2502
. As a left end
2502
′ of transmission arm
2502
is pressed down by the movement of a carriage (not shown) against a return spring
2506
, transmission gear
2505
engages roller gear
2504
, and drives a paper feed-in roller (not shown) fixed on shaft
2507
, which also rotatably supports roller gear
2504
.
The conventional mechanism employing the structures described above has the following problem.
Since transmission arm
2502
is not resilient, if left end
2502
′ of transmission arm
2502
is pressed too hard by the carriage, the force of transmission gear
2505
against roller gear
2504
is too much, and gears
2504
and
2505
will not rotate smoothly.
FIGS. 61-63
depict a conventional ink jet printer described in Japanese Utility Model Unexamined Publication No. 1101980/1991. Described is an ink jet head
2201
and a paper feed roller
2202
for feeding paper P to a print area
2201
a
where printing is performed. A transport roller
2203
, roller
2202
which is disposed downstream of paper feed roller
2202
relative to print area
2201
a
, rotates at a higher peripheral speed than paper feed roller
2202
and pulls paper P past paper feed roller
2202
. A paper holding plate
2204
holds paper P against paper feed roller
2202
. In a printer having the above construction, paper P is printed in print area
2201
a
while paper P floats.
However, with this type of printer, “blind striking” may occur in which ink is ejected from ink jet head
2201
despite the fact there is no paper P in print area
2201
a.
Blind striking occurs after the paper is detected by a paper detecting sensor disposed upstream of the print area but the paper fails to reach the print area due to a failure in paper feed, or the like. If the paper is detected by the paper detecting sensor, ink jet head
2201
operates on the assumption that the paper is present in the print area.
As shown in
FIGS. 61-63
, because there is nothing interposed between ink jet head
2201
and paper feed roller
2202
, when “blind striking” occurs, the ink ejected from ink jet head
2201
adheres to paper feed roller
2202
, thereby staining later sheets of paper P. This has been a serious problem with conventional printers having this construction.
Furthermore, a distal end of paper holding plate
2204
in the conventional printer shown in
FIGS. 61-63
functions to restrict the printing surface of the paper P. As noted above, in this conventional printer paper holding plate
2204
presses paper P paper feed roller
2202
. However, with inherent surface irregularities in paper feed roller
2202
, paper holding plate
2204
is pivotably displaced due to the effect of these irregularities and the pressure exerted on paper P by paper holding plate
2204
varies. This results in the gap between the printing surface and ink jet head
2201
varying, which adversely affects the print quality. In addition, since a plurality of paper holding plates
2204
are provided in the axial direction of paper feed roller
2202
, as shown in
FIG. 61
, paper holding plates
2204
are affected by the surface irregularities of paper feed roller
2202
at different locations in the axial direction thereof, and will pivot at different angles and at different instances, which will also adversely affect the print quality.
Further, ink jet printers print by discharging ink onto paper. If the printed paper is discharged by means of, for instance, a pair of rubber rollers, the ink that is not dry will adhere to the rubber rollers on the printed surface side, thereby smearing the ink on the printed surface of the paper.
Accordingly,
FIG. 64
illustrates an ink jet printer described in Japanese Utility Model Unexamined Publication No. 41277/1990 that has been proposed to overcome this problem. Paper P
1
, printed on by an ink jet head H, is discharged using a paper discharge roller
2401
made of a resilient material, such as rubber, and a plurality of star wheels
2402
which rotate with the paper nipped between star wheels
2402
and paper discharge roller
2401
. Star wheels
2402
are urged toward paper discharge roller
2401
by means of respective shafts
2403
each having a resiliency or spring characteristic.
However, the conventional printer employing the structure described above has the following
Hirano Seiichi
Kashiwabara Kazutoshi
Murayama Susumu
Yokoyama Koichiro
Yoshida Masanori
Barlow John
Brooke Michael S.
Seiko Epson Corporation
Stroock & Stroock & Lavan LLP
LandOfFree
Printer having a guide plate for transporting waste ink does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Printer having a guide plate for transporting waste ink, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Printer having a guide plate for transporting waste ink will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2547888