JPH0140694Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a ribbon cassette for use in printers, typewriters, etc., and particularly to a ribbon cassette for storing an endless loop of printing ribbon in a folded manner in a storage chamber.

Conventionally, a ribbon cassette in which an endless loop of printing ribbon is regularly folded and stored in a storage chamber is arranged in a ribbon cassette 1 as shown in Fig. 1.
A guide 5 for preventing the ribbon 2 from shifting in the vertical direction immediately before the pair of feed rollers 4 for feeding the printing ribbon 2 into the storage chamber 3;
6 were provided on the bottom wall 7 and top wall 8 of the cassette 1, respectively. However, in reality, the feed roller 4
The axes of the two roller shafts cannot be parallel due to the assembly accuracy and the play between the support hole provided between the bottom wall 7 and the top wall 8 and the roller shaft of the feed roller 4. , the printing ribbon 2 sometimes meandered in the vertical direction. When the printing ribbon 2 meander in this way, the lower edge 2a or upper edge 2b of the printing ribbon 2 in the width direction is pressed toward the bottom wall 7 or the upper wall 8, and in this state, the printing ribbon 2 is pushed toward the outlet opening direction (the direction toward the exit opening) of the storage chamber 3. When moving to the right (in Figure 1), the printing ribbon 2
Contact resistance with the bottom wall 7 or the top wall 8 hinders the movement of the print ribbon 2 in the direction of the exit opening, and the storage density of the print ribbon 2 becomes high only in the vicinity of the feed roller 4, or the print ribbon 2 is not folded regularly. It had the disadvantage that it could not be folded, reducing the ability to store ribbons in the storage compartment.

This invention was made to eliminate the above-mentioned drawbacks, and will be explained in detail below with reference to the drawings.

In FIGS. 2 to 4, ribbon cassette 1
0 has a substantially rectangular parallelepiped storage chamber 14 surrounded by a bottom wall 11, a top wall 12, and a side wall 13, and an endless loop printing ribbon 15 is placed in this storage chamber 14.
Most of the items are folded in an orderly manner. The printing ribbon 15 is sequentially fed into the storage chamber 14 by a pair of feed rollers 17 arranged at the entrance opening 16 of the storage chamber 14, and the ribbon is passed from the exit opening 18 of the storage chamber 12 through the exit guide section 19 to the exit slit 20. The cassette 10 is pulled out. After the drawn-out printing ribbon 15 passes through the printing section of the printer, it is drawn into the ribbon cassette 11 through the entrance slit 22 formed in the entrance guide section 21, and the direction of movement is changed by the guide pin 23, after which it is moved to the feed roller. 17 into the storage chamber 14 again. A leaf spring 29 provided near the exit slit 20 is used to apply appropriate tension to the ribbon portion adjusted between the exit slit 20 and the entrance slit 22 so that the ribbon portion does not loosen.

The pair of feed rollers 17 are each fixed on a roller shaft 24, and each roller shaft 24 is rotatably supported on holders 25 and 26 supported on the side wall 13, respectively. Gears are fixed to the lower portions of both roller shafts 24 so as to mesh with each other, and both feed rollers 17 are configured to interlock with each other. The driven side holder 26 is supported so as to be movable in the direction of the other driving side holder 25.
It is always urged toward the holder 25 by the spring 27. Further, the roller shaft 24 on the driven side is connected to the bottom wall 1.
1 and the upper wall 12 (only one is shown).

In the bottom wall 11, a protrusion, that is, a lower restricting portion 30 is formed around the guide pin 23 and protrudes from the inner surface of the bottom wall 11, and the lower restricting portion 30 prevents the printing ribbon 15 from meandering downward. Projections projecting downward from the inner surface of the upper wall 12, that is, first and second upper regulating parts 31 and 32, are formed on the entrance slit 22 side and the feed roller 17 side of the lower regulating part 30. Lower regulation part 30
The distance in the height direction between the upper regulating portions 31 and 32 is approximately equal to the width of the printing ribbon 15, as shown in FIG. Further, the shape of the second upper regulating portion 32 is approximately T-shaped, extending from the contact point of both rollers 17 along the outer periphery of both rollers on the storage chamber side, as shown in FIG. The second upper regulating part 3
The inner surface of the upper wall 12 closer to the exit slit 20 than the upper wall 12 is higher than the lower surface of the second upper regulating part 32.

In a ribbon cassette with such a configuration,
The printing ribbon drawn in from the entrance slit 22 is held approximately in the center between the bottom wall 11 and the top wall 12 by the first upper restriction part 31 and the lower restriction part 30. Therefore, the printing ribbon 15 is sent into the storage chamber 14 due to the inclination of the feed roller, etc.
Even if it is sent undulating in the vertical direction, it will not be strongly pressed against the bottom wall 11 or the top wall 12. Moreover, the entire time from when the printing ribbon 15 begins to come into contact with the feed roller 17 until it separates within the storage chamber 14,
Since upward meandering is restricted by the second upper restriction portion 32, the printing ribbon 15 does not come into contact with the inner surface of the upper wall 12, or only contacts it very lightly. Even if the printing ribbon 15 snakes downward, the printing ribbon 1
5 always comes into contact with the bottom wall 11 due to its own weight, so there is no effect. In short, unlike in the past, the printing ribbon is not strongly pressed against both the bottom wall 11 and the top wall 12 due to vertical meandering, and the storage chamber 1
The resistance when moving within 4 can be reduced.

As described above, with this invention, the upper edge of the printing ribbon is not pressed strongly against the inner surface of the upper wall of the storage chamber, so the printing ribbon can move smoothly in the direction of the exit opening, allowing longer printing ribbons to be passed in an orderly manner. It can be folded and stored.

[Brief explanation of the drawing]

Fig. 1 is a partial sectional view of a conventional ribbon cassette, Fig. 2 is a plan view of the ribbon cassette of this invention with the top wall removed, Fig. 3 is a plan view of the top wall, and Fig. 4 is a plan view of the ribbon cassette of the present invention with the top wall removed. FIG. 3 is a sectional view taken along line A-A in FIG. 2; In the figure, 11 is a ribbon cassette, 14 is a storage chamber,
15 is a printing ribbon, 16 is an entrance opening, 17 is a feed roller, 18 is an exit opening, and 32 is an upper regulating portion.

Claims (1)

[Claims for Utility Model Registration] A ribbon storage chamber having an entrance opening, an exit opening, and a height larger than the width of the endless loop printing ribbon is provided, and the printing ribbon pulled out from the exit opening is placed on one side of the ribbon storage chamber. In a ribbon cassette that is pulled in from an entrance opening by a pair of feed rollers provided in the ribbon storage chamber and stored in a folded manner in a ribbon storage chamber, the printing ribbon comes into contact with the inner surface of the upper wall of the ribbon cassette near the feed rollers and then leaves the ribbon. The protrusion 32 that protrudes downward until the
1. A ribbon cassette characterized in that the inner surface of the upper wall of the ribbon storage chamber on the outlet opening side of the protrusion is higher than the lower surface of the protrusion.