Printing – Stenciling – Traveling-inker machines
Reexamination Certificate
2002-02-05
2003-09-16
Evanisko, Leslie J. (Department: 2854)
Printing
Stenciling
Traveling-inker machines
C101S114000, C118S406000
Reexamination Certificate
active
06619197
ABSTRACT:
BACKGROUND OF THE INVENTION
1. FIELD OF THE INVENTION
The present invention relates to a screen printing apparatus.
2. DESCRIPTION OF THE CONVENTIONAL ART
A conventional screen printings apparatus is, for example, as shown in FIGS.
11
(
a
)-
11
(
b
), constituted by a base plate
101
on which a substrate to be printed
102
is mounted, and a screen printing plate
103
provided in a tensional manner on the base plate
101
in substantially parallel to an upper surface of the base plate, and is structured such as to pass a printing paste
105
supplied on the screen printing plate
103
by a paste supplying means
106
in a manner shown in FIG.
11
(
a
) through a pattern hole (not shown) of the screen printing plate
103
due to a movement of a squeegee
104
as shown in FIG.
11
(
b
), there by forming a pattern on the substrate to be printed
102
. In this case, FIG.
11
(
c
) is a view showing a state that a movement of the squeegee reaches a terminal end, and FIG.
11
(
d
) is a view showing a state of moving the squeegee in an opposite direction so as to start printing.
In this case, in order to stably executed the screen printing, it is necessary to control a viscosity of the paste, a performance of the screen printing plate (a thickness of the screen printing plate, a tension balance, an accuracy, a strength, a service life and the like), a performance of the squeegee (an accuracy, a hardness, an angle and the like), a mechanical performance (an accuracy, a speed control and a pressure control) and the like so as to always keep in a uniform state.
However, in the conventional screen printing apparatus mentioned above, since the paste
105
is applied to all over the screen printing plate
103
in an exposed manner, the following problems are provided.
{circle around (
1
)} Since a lot of expensive paste which costs between some tens of thousand yen and some hundreds of thousand yen is left on the screen printing plate, a lot of loss money is generated.
{circle around (
2
)} Since the paste is directly supplied onto the screen printing plate, a lot of time is required for changing the paste, so that an operation efficiency is largely reduced.
{circle around (
3
)} Since the paste is exposed to an air so as to be oxidized and a property is deteriorated, an electric property and the like after printing are deteriorated.
{circle around (
4
)} Since a solvent mixed in the paste is evaporated and the viscosity is changed, a printing property is significantly deteriorated.
{circle around (
5
)} Since the evaporated solvent has a strong odor, a problem relating to an environment pollution is generated.
{circle around (
6
)} Since the viscosity of the paste is changed due to an influence of a temperature change, a printing performance is significantly deteriorated.
{circle around (
7
)} Since dusts are mixed within the paste, the pattern formed by the printing is disconnected and shorted. Then, in order to carry out a countermeasure thereof, a clean room which is expensive and hard to be controlled is required.
Further, in order to solve the problem mentioned above, in Japanese Unexamined Patent Publication No. 6-210829, as shown in
FIG. 12
, there is proposed a method of charging a printing paste
205
within a chamber
209
, supplying and recovering the paste
205
through a supply port
207
which can be opened and closed, by rotating a roller
206
, and printing by a front blade
208
. In this case, reference numeral
202
denotes a substrate to be printed, reference numeral
203
denotes a screen printing plate and reference numeral
204
denotes a rear blade.
However, in this method, the following problems are provided.
{circle around (
1
)} Since the paste is supplied due to a rotational force of the roller
206
, it is necessary that the roller
206
and the paste are directly in contact with each other, so that a lot of time is required for cleaning and maintaining the roller.
{circle around (
2
)} Since the paste
205
is directly supplied within the chamber
209
, it is necessary to carry out a maintenance such as a periodical cleaning or the like, so that a long time is required for the maintenance operation.
{circle around (
3
)} Since the paste
205
is directly supplied within the chamber
209
, a lot of time is required for changing the paste, so that an operation efficiency is largely reduced.
{circle around (
4
)} Since a lot of expensive paste which costs between some tens of thousand yen and some hundreds of thousand yen per 1 kg is left within the chamber
209
, a lot of loss money is generated.
{circle around (
5
)} Since an air is mixed at a time of supplying the paste
205
within the chamber
209
, a defect such as a wire disconnection, a chip or the like is generated in a pattern after printing.
{circle around (
6
)} Since an inner portion of the chamber
209
is exposed to the air, the paste is oxidized or deteriorated.
{circle around (
7
)} It is necessary to control an elastic force of the squeegee, a wetting property of a surface of the squeegee and the like in correspondence to a property of the paste, however, in this example, since the squeegee is executed by the front blade
208
constituted by a thin plate metal, it is possible to adjust only on the basis of the metal, so that it is impossible to adjust a suitable elastic force.
SUMMARY OF THE INVENTION
The present invention is made by taking the points mentioned above into consideration, and an object of the present invention is to provide a screen printing apparatus which can always keep a printing paste in a uniform state, can print stably at a high accuracy, and can use an expansive paste with no waste, whereby it is possible to solve all of the problems mentioned above.
A screen printing apparatus provided with a means for solving the problem mentioned above is as follows.
(1) A screen printing apparatus for pattern-forming of a printing paste on a screen printing plate onto a substrate to be printed by moving a squeegee in a predetermined direction, comprising:
a bag-like container in which the printing paste is charged;
a mechanism for receiving the bag-like container and pressurizing the bag-like container;
a printing paste supply plate provided with a printing paste supply port; and
an elastic squeegee in which a back surface is formed at a fixed angle corresponding to an angle at a time of printing and a front surface is integrally formed with a hard thin plate,
wherein the mechanism for pressurizing the bag-like container is connected to the back surface side of the printing paste supply plate, the back surface of the squeegee is brought into contact with the printing paste supply port in the front surface side of the printing paste supply plate, and the screen printing apparatus is provided with a printing paste supply mechanism capable of being opened and closed through a vertical movement so as to supply a predetermined amount of printing paste, and a scraper for scraping up the printing paste on the screen printing plate.
(2) A screen printing apparatus for pattern-forming of a printing paste on a screen printing plate onto a substrate to be printed by moving a squeegee in a predetermined direction, comprising:
a step of moving upward the squeegee so as to open a printing paste supply port;
a step of pressurizing a container in which the printing paste is charged so as to supply a predetermined amount of printing paste;
a step of moving downward the squeegee after supplying the predetermined amount of printing paste so as to close the printing paste supply port and simultaneously arranging the squeegee on a screen printing plate; a step of printing with the hard thin plate side of the elastic squeegee in which a front surface is integrally formed by a hard thin plate; and
a step of scraping up the printing paste on the screen printing plate by a scraper after printing, whereby the printing is carried out by repeating these steps.
(3) A screen printing apparatus in which a bag-like container charged with a printing paste is manufactured by a step of welding three peripheral po
Miyata Takamasa
Murakami Takehiko
Murano Shunji
Evanisko Leslie J.
Minami Co. Ltd.
Sheets Kendal M.
Zito Joseph J.
Zito tlp
LandOfFree
Screen printing apparatus having vertically movable squeegee... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Screen printing apparatus having vertically movable squeegee..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Screen printing apparatus having vertically movable squeegee... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3034216