Incremental printing of symbolic information – Ink jet – Ejector mechanism
Reexamination Certificate
2001-03-28
2003-11-25
Stephens, Juanita (Department: 2853)
Incremental printing of symbolic information
Ink jet
Ejector mechanism
C347S047000, C347S033000
Reexamination Certificate
active
06652062
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a liquid discharge recording head for recording on a recording medium by discharging ink from the discharge port group provided for an orifice plate. The invention also relates to a method of manufacture therefor.
2. Related Background Art
A liquid discharge recording apparatus is such that, for example, ink is supplied to a liquid discharge recording head, and by driving ink droplet discharging means, such as piezoelectric elements or electrothermal converting elements provided for a liquid discharge recording head, in accordance with image data in order to form images on a recording sheet or some other recording medium by means of ink dot patterns. The ink discharge recording apparatus that performs recording by discharging ink from the discharge ports of the liquid discharge recording head is known as a recording apparatus having such excellent advantages as a lesser amount of noises, a capability of recording at high speed, among some others.
FIG. 67
is a perspective view which shows the conventional liquid discharge recording head in a state of partially broken in representation, and also, in a state where the orifice plate is separated.
FIG. 68
is a perspective view which shows the liquid discharge recording head represented in
FIG. 67
in a state where the orifice plate is bonded to it.
For the conventional liquid discharge recording head
315
of the kind, a heater board
301
, having electrothermal converting elements (discharge heaters
301
a
) which are the elements that generate energy for discharging ink, and wiring for supplying electric power to the discharge heaters
301
a
formed on a silicon base plate using silicon film formation process, is set by means of die bonding on a supporting base (base plate
304
) formed by aluminum, ceramics, or the like. The base plate
304
also functions as the heat sink that radiates heat generated on the heater board
301
along with the driving of discharge heaters
301
a
and cools it.
On the heater board
301
, there is arranged the ceiling plate
305
that forms ink flow paths. The ceiling plate
305
is provided with the nozzles
307
which constitute ink flow paths communicated with the discharge ports
306
a
of the orifice plate
306
formed in a recess on the bottom face of the ceiling plate
305
; the common liquid chamber
308
which serves as a sub-tank for supplying ink to the nozzles
307
each formed in a recess on the bottom face of the ceiling plate
305
; and the ink supply port
309
through ink is supplied to the common liquid chamber
308
.
Further, on the base plate
304
, a chip tank
311
to form ink passage
311
a
to guide ink to the ink supply port
309
from an ink storage tank, or sub-tank, or the like (not shown) arranged on the upstream side of the liquid discharge recording head
315
in the ink flow direction.
A front plate portion
311
b
is formed on the surface to which the nozzles
307
of the chip tank
311
is open. The front plate portion
311
b
functions to bond and hold the orifice plate
306
having the discharge ports
306
a
open at the same intervals as those between nozzles
307
themselves on the circumferential area of the discharge ports
306
a
, and also, functions to support the orifice plate
306
so as to enable the orifice plate
306
to withstand sufficiently against the force exerted by the time of attachment or detachment, and the holding pressure exerted by the cap member (not shown) arranged for the recording apparatus main body at the time of capping operation.
Here, in the specification hereof, the structure of liquid discharge recording head which is in a state that the orifice plate is removed is called “recording head main body”.
In this respect, the ceiling plate
305
is formed by resin, such as polysulfone, polyether sulfone, polypropylene, denatured polyphenylene oxide, polyphenylene sulphide, or liquid crystal polymer or formed by such material as ceramics, silicon, nickel, or carbon.
Also, the orifice plate
306
is formed by metallic plate, such as SUS (stainless steel), Ni, Cr, or Al, or a resin mold, resin film material, or the like, such as polyimide, polysulfone, polyether sulfone, polyphenylene oxide, polyphenylene sulfide, or polypropylene, or further, formed by silicon, ceramics, or the like.
Now, the description will be made of the outline of assembling process of the liquid discharge recording head.
At first, the discharge heaters
301
a
on the heater board
301
set on the base plate
304
and the nozzles
307
of the ceiling plate
305
which is arranged relatively therefor are aligned to be in agreement in high precision, and using bonding means such as bonding agent or pressure means such as pressure spring (not shown) the heater board
301
and the ceiling plate
305
are kept closely in contact for the formation of ink flow paths.
Then, the chip tank
311
is incorporated on the base plate
304
to connect the ink supply port
309
of ceiling plate
305
with the ink passage
311
a
of chip tank
311
. At this juncture, the front plate portion
311
b
of chip tank
311
covers the front end of heater board
301
b
that forms the edge faces of ink flow paths, and the outer side of front end of ceiling plate
305
b
as well. In this respect, the edge faces of ink flow paths
301
b
and
305
b
are structured to protrude from the surface of front plate portion
311
b
by several tens of &mgr;m to several hundreds of &mgr;m approximately.
Next, the orifice plate
306
is bonded by use of bonding agent or some other bonding means to the edge faces of ink flow paths
301
b
and
305
b
which are formed to protrude by the heater board
301
and the ceiling plate
305
. At this juncture, the surface of the front plate portion
311
b
is formed to be retracted from the ink flow path edge faces
301
b
and
305
b
as described earlier so as not to impede bonding of the orifice plate
306
and the ink flow edge faces
301
b
and
305
b.
Then, in the last process that follows, bonding agent or sealant is poured into the gap (the stepped portion of several tens of &mgr;m to several hundreds of &mgr;m between the front plate portion
311
b
and the ink flow path edge faces
301
b
and
305
b
) formed between the area where no discharge ports
306
a
are arranged on the backside of the orifice plate
306
and the front plate portion
311
b
, thus completing the bonding of orifice plate
306
.
In this way, the assembling process of the liquid discharge recording head
315
is completed.
Also, as another conventional liquid discharge recording head, there exists the structure in which, as shown in
FIG. 69
, the central portion of front face of an orifice cover
312
is removed, and additionally arranged to cover only four sides of orifice plate
306
.
In a general case where a liquid discharge recording head is structured so that the orifice plate is bonded to the opening face of liquid flow paths (nozzles) of a recording head, the ink discharge face is cleaned by the wiping operation of recovery device as shown in
FIG. 70
, and then, as in the wiping operation b shown in
FIG. 70
, the edge portion of the wiping blade
321
is in contact with the orifice plate edge portion
306
c
as if to draw it. As a result, the orifice plate
306
is liable to be peeled off from the recording head
315
at the edge portion
306
c
. Also, the leading end of the wiping blade
321
slidably rubs the facing end
306
b
of the orifice plate
306
. As a result, there is a possibility that peeling off occurs at the edge portion of the orifice plate other than the edge portion at
306
c
by the repetition of wiping operation.
If the edge portion of orifice plate should be peeled off even slightly, it advances further by repetition of wiping operations to follow, and the recording head is damaged beyond recovery ultimately. In order to avoid such problem as this, the structure is arranged as shown in
FIG. 69
to provide an orifice cover
312
to cover the four sides of an orifice
Fukazawa Hideo
Hatasa Nobuyuki
Koizumi Yutaka
Tajima Hiroki
Umeyama Mikiya
LandOfFree
LIQUID DISCHARGE RECORDING HEAD WITH ORIFICE PLATE HAVING... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with LIQUID DISCHARGE RECORDING HEAD WITH ORIFICE PLATE HAVING..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and LIQUID DISCHARGE RECORDING HEAD WITH ORIFICE PLATE HAVING... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3184618