JPH0696319B2 - Ink ribbon cassette - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink ribbon cassette used in a printing device or the like.

2. Description of the Related Art In recent years, there has been a strong demand for improvement in printing quality as printers have become more sophisticated.

However, in impact dot printers, the gap between the print paper and the tip of the print head must be set to about 0.3 mm, so the gap between the print ribbon and the print ribbon is extremely small. The problem is that the printing paper is contaminated by the ink ribbon located on the printing surface.

In order to prevent the printing paper from being contaminated, an ink ribbon cassette has been used in which a ribbon mask is interposed between the printing paper and the ink ribbon.

FIG. 4 is an exploded perspective view of a conventional ink ribbon cassette, 1 shows the entire ink ribbon cassette, 2 is an ink ribbon, 3 is a delivery port 3a of the ink ribbon 2 and a protrusion.
An arm portion 3b for guiding the ink ribbon 2 to the printing position, and an arm portion 4 for guiding the ink ribbon 2 used for printing to the inside of the ink ribbon cassette 1 with an inlet 4a for the ink ribbon 2 and a projection 4b. Reference numeral 5 has holes 5a and 5b that engage with the protrusions 3b and 4b, and also has an opening 5c that exposes the ink ribbon 2 toward a print sheet (not shown in the figure). 2 is a ribbon mask that prevents contact with a portion of the second print not used.

FIG. 5 is a cross-sectional view of a main part of a printing apparatus using a conventional ink ribbon cassette. 6 is a print head having a flat wire guide 6a, 7 is a cylindrical platen, and 8 is a state wound around the platen 7. It is the printing paper held by.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention However, in the above conventional configuration, the relative positional relationship between the ink ribbon cassette 1 and the print head 6 changes depending on the mounting state of the ink ribbon cassette 1, so that, for example, when the ink ribbon cassette 1 is slightly inclined. When attached, the ribbon mask 5 comes into contact with the upper or lower part of the wire guide 6a together with the ink ribbon 2, and the ink impregnated in the ink ribbon 2 adheres to the inside of the ribbon mask 5 and goes to the front side from the opening 5c. There is a problem that it flows out, adheres to the printing paper 8, and stains the printing paper 8. This becomes more remarkable especially when the wire guide 6a has a concave surface along the outer periphery of the platen 7.

Further, in the above-mentioned conventional configuration, the ribbon mask 5 is simply the protrusion 3b.
And 4b are only retained in a hooked state, so that bending or twisting occurs in the vicinity of the central portion, and the ribbon mask 5 comes into contact with the upper or lower portion of the wire guide 6a together with the ink ribbon 2, In some cases, the same problem as the above problem may occur.

Means for Solving the Problems The present invention includes two ribs protruding forward at upper and lower positions with an exposed portion of an ink ribbon in the center.
A ribbon mask that is in contact with two ribs is provided, and both the left and right ends of the ribbon mask are pulled backward, and the ribbon mask is fixed to the arm while being curved forward.

Action With the above configuration, since the ribbon mask is curved toward the recording medium, the distance from the upper and lower portions of the wire guide to the ribbon mask becomes longer, and tension acts on the central portion of the ribbon mask and also the upper and lower portions. Due to the tension, the ribbon mask itself is less likely to be deformed.

Embodiment 1 FIG. 1 is an exploded perspective view of an ink ribbon cassette according to an embodiment of the present invention, 11 shows the entire ink ribbon cassette, 12 is an ink ribbon, and 13 is an ink ribbon 12.
In addition to having a delivery port 13a and a protrusion 13b, ribs 13c and 13d protruding toward the printing paper above and below the printing area, and an arm portion for guiding the ink ribbon 12 to the printing position, 14 is an inlet port for the ink ribbon 12. In addition to having 14a and a protrusion 14b, ribs 14c and 14d protruding toward the print sheet above and below the print area, and an arm portion for guiding the ink ribbon 12 used for printing into the ink ribbon cassette 11, 15 is a protrusion 13b. And 1
In addition to having holes 15a and 15b that engage with 4b, and an opening 15c that exposes the ink ribbon 12 toward the printing paper, the ribs 13c and 13d and 14c and 14d are in contact, and the printing paper is the ink ribbon. It is a ribbon mask that prevents from touching the part of 12 that is not used for printing. The third
As shown in the figure, the ribbon mask 15 has ribs 13c, 13d on the back surface,
14c and 14d, and holes 15a and 15b
Since it has a structure in which it is hooked on b and 14b and fixed in a state in which tension is applied in the directions indicated by arrows A and B at the central portion, the vicinity of the printing area is concave toward the recording medium.

FIG. 2 is a cross-sectional view of a main part of a printing apparatus using the ink ribbon cassette of this embodiment, 6 is a print head, 7 is a platen, and 8 is printing paper, and these have the same constructions as the conventional example. Ribbon mask 15 is platen 7 with ribs 14c and 14d.
Since it is pressed toward, the shape is further curved along the curved surface of the platen 7, and the ribbon mask 15
And the gap between the ink ribbon 12 is secured.

As described above, according to the present embodiment, since the ribbon mask 15 itself is under tension, the ribbon mask 15 itself is not easily deformed, and the central portion of the ribbon mask 15 is concave toward the printing paper 8. Therefore, the distance from the wire guide 6a to the ribbon mask 15 can be sufficiently secured, the contact between the ribbon mask 15 and the wire guide 6a can be prevented, and the printing paper 8 can be prevented from being soiled.

EFFECTS OF THE INVENTION The present invention includes two ribs that protrude forward at upper and lower positions with the exposed portion of the ink ribbon in the center.
The ribbon mask is provided in contact with the two ribs, and the left and right ends of the ribbon mask are pulled backward respectively to bend the ribbon mask forward, and the ribbon mask is fixed to the arm portion. Since the ribbon mask is curved toward the recording medium, the distance from the upper and lower parts of the wire guide to the ribbon mask becomes long, and tension acts on the central part of the ribbon mask and also on the upper and lower parts of the ribbon mask. The mask itself is unlikely to be deformed, contact between the ribbon mask and the wire guide can be prevented, and stains on the printing paper can be prevented.

[Brief description of drawings]

FIG. 1 is an exploded perspective view of an ink ribbon cassette according to an embodiment of the present invention, FIG. 2 is a sectional view of a main part of a printing apparatus using the ink ribbon cassette, FIG. 3 is a perspective view of the ink ribbon cassette, and FIG. Is a perspective view of a conventional ink ribbon cassette, and FIG. 5 is a cross-sectional view of the main part of a printing apparatus using the ink ribbon cassette. 6 ... Print head, 7 ... Platen, 8 ... Printing paper, 11 ... Ink ribbon cassette, 12 ... Ink ribbon, 13 ... Arm, 13a ... Outlet, 13b ... Projection, 13c, 13d ... Rib, 14 ... Arm, 14a ... inlet, 14b ... protrusion, 14c, 14d ... rib, 15 ... ribbon mask, 15a, 15b ... hole, 15c ... opening.

Claims (1)

[Claims] 1. An ink ribbon, a housing portion for housing the ink ribbon, a first arm portion provided with an ink ribbon delivery port, and a second arm provided with the ink ribbon delivery port. And two ribs horizontally protruding forward at upper and lower positions with the ink ribbon between the first arm portion and the second arm portion sandwiched in the center. And a ribbon mask which is provided on at least one of the second arm portion and is made of a flexible material and which abuts the two ribs and covers at least a part of the exposed portion. An ink ribbon cover characterized in that the ribbon mask is fixed to the first arm portion and the second arm portion in a state where the left and right ends are respectively pulled backward and the ribbon mask is curved forward. set.