Ink-jet printer head

Details Ink-jet printer head Ink-jet printer head

2001-09-28

2003-09-16

Nguyen, Lamson (Department: 2853)

Incremental printing of symbolic information

Ink jet

Ejector mechanism

C347S063000, C347S064000, C347S065000

Reexamination Certificate

active

06619779

ABSTRACT:

CROSS-REFERENCE TO RELATED APPLICATION
This application claims the benefit of Korean Application No. 2000-57512, filed Sep. 29, 2000, in the Korean Industrial 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 an ink-jet printer head, and more particularly, to a thermal ink-jet printer head of an upward ejecting type and which has improved on the construction of an ink channel so that the area occupied by a unit nozzle can be reduced and an ejected ink droplet can be stabilized.
2. Description of Related Art
An ink ejecting method applied to an ink-jet printer head is generally classified into a thermal driving method and a piezoelectric driving method. In the thermal driving method, ink is instantaneously heated by a resistance heating element, thereby generating and expanding a bubble, and is ejected through a nozzle by the pressure of the bubble. In the piezoelectric driving method, ink is ejected through the nozzle by the pressure generated by the displacement of a piezoelectric element.
Further, the ink-jet printer head of the thermal driving method is classified into a side ejecting type of FIG.
1
and an upward ejecting type of
FIG. 2
according to an ink ejecting direction with respect to a base plate and a nozzle plate.
An ink-jet printer head
21
of the side ejecting type as shown in
FIG. 1
comprises an ink channel
23
, a nozzle
26
formed at one end of the ink channel
23
, and a resistance heating element
2
for instantaneously heating the ink in the ink channel
23
to generate and expand a bubble
22
, wherein an ink droplet
29
around the nozzle
26
is ejected by the pressure of the bubble
22
.
The ink-jet printer head of the upward ejecting type as shown in
FIG. 2
, comprises a nozzle
36
, an ink chamber
39
, an ink channel
34
disposed at a side of the ink chamber
39
for supplying ink therethrough, and a resistance heating element
2
for heating the ink in the ink chamber
39
to generate and expand a bubble, wherein an ink droplet is ejected through the nozzle
36
by the expansion pressure of the bubble generated and expanded in the ink chamber
39
.
The aforementioned conventional ink-jet printer head, however, has shortcomings of the so-called back-flow of ink, which means that ink flows back into the inner side of the ink channel
23
or
34
due to the expansion pressure of the bubble generated when ejecting ink. The back-flow causes a cross-talk during a printing process, and thus causes a deteriorated print quality.
To solve the problem as described above, the conventional side ejecting type has an elongated ink channel
23
and a protective barrier
24
made of a polymer or the like, which is disposed above a heat driving section including the resistance heating element
2
, for preventing the back-flow of ink. However, in the construction as described above, since a unit nozzle occupies a broad area of the base plate, it is required for the ink-jet printer head to be lengthened accordingly, and thus the manufacturing process thereof is complicated.
The conventional upward ejecting type as shown in
FIG. 2
has a protruding portion
37
with a neck formed on the ink channel
34
connected to the ink chamber
39
, thereby preventing the back-flow of ink. However, due to a complicated manufacturing process and structure, the manufacturing becomes difficult.
Meanwhile, an ink manifold of the conventional ink-jet printer head is formed by wet etching, and the ink channel thereof is formed by laser ablation.
The problem is that the laser ablation deteriorates a quality of the treated surface. Also, the wet etching has problems such as a long treating time, use of chemicals that causes environmental problems, and imprecise treatment.
SUMMARY OF THE INVENTION
In order to improve the ink-jet printer head as described above, an object of the present invention is to provide an upward ejecting type of a thermal ink-jet printer head capable of reducing an area occupied by a unit nozzle, and thus enhancing a printing speed and a print resolution by improving a structure of an ink channel.
Another object of the present invention is to provide an upward ejecting type of a thermal ink-jet printer head capable of stabilizing an ejected ink droplet, and thus enhancing a printing efficiency by improving a structure of an ink channel.
Additional objects 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.
To achieve the above and other objects, an ink-jet printer head in accordance with the present invention includes a base plate having ink channels penetrating therethrough, a donut shaped heat driving section formed in the base plate and encircling an exit of the ink channels, an ink chamber barrier stacked on the base plate for serving as a side wall of an ink chamber, and a nozzle plate stacked on the ink chamber barrier and having a nozzle for ejecting out the ink in the ink chamber.
Here, preferably, the base plate, the ink channels, the ink chamber, and the heat driving section are symmetrical with respect to a shared axis thereof.
The ink channels include an ink manifold formed by hollowing the lower portion of the base plate to have a predetermined area therein and an ink supplying path formed by being hollowed to have a narrower area therein than that of the ink manifold, which connects the ink manifold with the ink chamber.


REFERENCES:
patent: 4896171 (1990-01-01), Ito
patent: 4922265 (1990-05-01), Pan et al.
patent: 6340223 (2002-01-01), Hirata

Affiliated with

Also associated with

Rating

Ink-jet printer head 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 printer head, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Ink-jet printer head will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-3108987