Typewriting machines – Means auxiliary to typewriting function – Frame – casing – or support for typewriter
Reexamination Certificate
2001-04-24
2002-11-26
Colilla, Daniel J. (Department: 2854)
Typewriting machines
Means auxiliary to typewriting function
Frame, casing, or support for typewriter
C400S663000
Reexamination Certificate
active
06485210
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a device used in printers for compressing paper using clamshell-type during a printing process and, more particularly, to a clamshell device for printers having a simple construction and accomplishing the recent trend of compactness, lightness, smallness and thinness of its parts, thus being preferably usable in compact printers, the clamshell device being also designed to improve work efficiency during its fabrication and effectively produced through mass production.
2. Description of the Prior Art
FIG. 1
is a view showing a conventional clamshell device for printers. As shown in the drawing, the conventional clamshell device comprises a cover
11
, which is hinged to a main body (not shown) at one end thereof so as to be openable. A rubber roller
14
mounted to the roller frame
12
, which is hinged to the cover
11
, rotate itself and compresses the paper to be fed to a printer head while maintaining desired tension of the paper during a printing process. A sliding frame
13
hinged to the main body use the elastic force of spring
13
′, which is normally connected to the main body, so as to support the roller frame
12
. A locking member
16
is hinged to the end of the cover
11
, and is selectively caught by a stopper
17
of the main body, thus limiting a rotation of the cover
11
. A holding roller
15
is mounted to the main body and comes into close contact with the rubber roller
14
so as to support the paper, which is moving into the printer head (not shown) during a printing process of the printer.
In the conventional clamshell device, the rubber roller
14
and the holding roller
15
are completely contact each other during a printing process, thus give a compressing force to the paper passing through the nip between the two rollers.
When the cover
11
is rotated in a cover closing direction as shown by the arrow in
FIG. 1
, the roller frame
12
hinged to the cover
11
is also rotated in the same direction. The rubber roller
14
, mounted to the end of the roller frame
12
, is brought into compression contact with the holding roller
15
of the main body, thus compressing the paper fed to the printer head of the printer. Therefore, the paper is fed to the printer head under sufficient tension during a printing process.
In order to maintain the closed position of the cover
11
, it is necessary for the stopper
17
to stably catch the locking member
16
provided at the end of the cover
11
. When the stopper
17
fails to catch the locking member
16
during such a cover closing action, the roller frame
12
is undesirably rotated clockwise since the spring
13
′ normally applies the clockwise moment to the sliding frame
13
. In such a case, it is almost impossible to maintain the compression contact of the rubber roller
14
with the holding roller
15
. When the rubber roller
14
fails to come into compression contact with the holding roller
15
as described above, the two rollers
14
and
15
cannot compress the paper and fail to smoothly feed the paper to the printer head of the printer.
This means that the compression force, applied to the paper during an operation of the clamshell device for printers, is accomplished by the engagement of the locking member
16
of the cover
11
with the stopper
17
of the main body. In addition, the spring
13
′ applies elastic force to the sliding frame
13
so as to damp any impact generated in the clamshell device during a cover opening or closing action.
However, the conventional clamshell device for printers is problematic in that for making complete compression contact between the rubber roller and the holding roller, it is necessary a locking structure additionally. Other problems of the conventional clamshell device reside in that the device does not have any automatic tilting means, and that it has a complex construction, in addition to an excessive number of parts. Furthermore, the parts of the conventional clamshell device for printers are large in size, and so the conventional clamshell device cannot be usable in compact and small-sized printers.
SUMMARY OF THE INVENTION
The object of the present invention is to provide a clamshell device for printers, which has a simple construction and accomplishes the recent trend of compactness, lightness, smallness and thinness of its parts, thus improving work efficiency during assemblage and being easily produced in commercial quantities.
In order to accomplish the above object, the present invention provides a clamshell device for printers, comprising: a main body including a paper roll seat opening used for installing a paper roll therein, with a guide surface, which is formed at the upper edge of each sidewall, inclined at an angle of inclination; a roller frame hinged to the main body and closing the paper roll seat opening, the roller frame having a holding roller coming into compression contact with a rubber roller of the main body so as to give compression force to paper passing through the nip of the rubber and holding rollers; a locking post movably set within two longitudinal slits of the roller frame at its side wall, said locking post being movable along the guide surfaces of the main body while being changed in its position within the longitudinal slits during an either directional rotation of the roller frame relative to the main body; and a spring held on the roller frame at one end thereof and on the main body at the other end thereof, and normally applying elastic force to the roller frame.
In this invention, a stopper is formed on the main body for preventing an excessive rotation of the roller frame.
In addition, the guide surfaces has a shoulder profile capable of stably holding the locking post in cooperation with the elastic force of the spring at a time the holding roller of the roller frame comes into compression contact with the rubber roller of the main body.
In the preferred embodiment of this invention, the spring is held by the locking post of the roller frame at one end thereof and by a spring holding shaft at the other end thereof, the spring holding shaft being provided around the bottom of the paper roll seat opening.
REFERENCES:
patent: 4860031 (1989-08-01), Lejcek
patent: 5201588 (1993-04-01), Sakai et al.
patent: 5230576 (1993-07-01), Sone
patent: 6345782 (2002-02-01), Nakayama et al.
Colilla Daniel J.
Ladas & Parry
Samsung Electro-Mechanics Co. Ltd.
LandOfFree
Clamshell device for printers does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Clamshell device for printers, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Clamshell device for printers will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2923398