JPH0114446Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a ribbon cassette that is set in a print head of a printer.

A ribbon cassette of a type in which a portion of an endless ink ribbon is pulled out of the cassette from a ribbon storage chamber of the cassette, and the ink ribbon is fed into the ribbon storage chamber by a feed roller is well known. Further, the print head faces the platen with a small gap therebetween. When the ribbon cassette is set in the print head, the ink ribbon pulled out of the cassette is inserted into this small gap from above and set so as to be located in front of the print head. At this time, the ink ribbon often gets caught on the front surface of the print head and gets twisted, and when you try to untwist it, your fingertips get smeared with ink.

Therefore, the object of the present invention is to prevent the above-mentioned problems from occurring when a ribbon cassette is assembled.

To explain an example, in FIG.
The case 1 has a recess 1a on the right side for inserting the print head 6, and a feed roller 2 is rotatably supported in the center, and around it is a recess 1a for inserting the print head 6.
Four ink cartridges 3b, 3c, 3m, and 3y impregnated with blue, red, and yellow inks are arranged radially. Feed roller 2 is the second
As shown, four transfer surfaces 2b, 2c, 2m, 2
y are formed coaxially, and ink cores 4b, 4c, 4m, and 4y of the ink cartridge are in contact with each transfer surface. The shaft portion of the feed roller 2 protrudes from the lower surface of the case 1, and a gear 5 is fixed to the protruding end.
When this ribbon cassette is set in a carriage (not shown) equipped with a printing head 6, this gear 5 is driven to rotate when the carriage is moved, thereby rotating the feed roller 2 counterclockwise in Figure 1. . As shown in the second diagram, the ink ribbon 7 has black, blue, red, yellow color bands 7b, 7c, 7m,
7y, which are each transfer surface 2b, 2c, 2
It is in elastic contact with m and 2y via a pressing spring 8 shown in FIG. This ink ribbon 7 is endless, and most of it is packed into the ribbon storage chamber 9.
The ink ribbon 7 is rotated by the rotation of the feed roller 2.
is fed into the ribbon storage chamber 9, while being pulled out from the ribbon storage chamber 9. A roller 11 rotatably supported by a shaft portion 10 integral with the case 1 is inserted near the exit of the ink ribbon 7, and the ink ribbon 7 is pressed against this roller 11 by a pressure spring 12. . As a result, a load is applied to the ink ribbon 7 when it is pulled out from the ribbon storage chamber 9, and the ink ribbon 7 pulled out to the outside becomes tense. In this embodiment, the pressure spring 12 is bent into a substantially L-shape, and the bent base 12a is attached to the case 1 in the following manner. That is, a protrusion 14 is formed in a part of the partition wall 13 that partitions the ribbon storage chamber 9, and a press lever 15 is disposed close to the outside (upper side in FIG. 1) of the protrusion 14, and the pressure lever 15 is arranged around the shaft 16 of the protrusion 14. It is swingably attached to case 1. As shown in FIG. 3, the pressing lever 15 has a tongue portion 17 extending from its lower portion, and swings clockwise in FIG. I can do it. Furthermore, press lever 1
A protrusion 18 is formed on the inner surface of 5. The base 12a of the press spring 12 is inserted between the partition wall 13 and the press lever 15, and at this time, the protrusion 14 pushes the base 12a upward, and the swing base of the press lever 15 and the protrusion 18 on both sides It acts to push down the base 12a. Due to this clamping structure, the base portion 12a of the pressure spring 12 will not come off unless it is pulled out with a force above a certain level.

Furthermore, a pair of wedge-shaped protrusions 12b are integrally bent in the middle of the pressing spring 12, that is, at a position slightly in front of the roller 11. And this protrusion 12
A column 19 having a semicircular cross section is formed integrally with the cassette 1, and faces b with a small distance therebetween.

The operation of setting the ribbon cassette into the printer will now be explained. When both sides of the cassette are grasped with the hands, the pressing lever 15 is pushed in with the fingertips against the spring force of the pressing spring 12 as shown in FIG. Then, the base portion 12a of the pressing spring 12 is pressed and bent using the protrusion 14 as a fulcrum. As a result, the protrusion 12b comes into contact with the pillar 19, and the wedge effect causes the pressing spring 12 to strongly press the ink ribbon 7 against the roller 11. Therefore, roller 11
The free rotation of the ink ribbon 7 is inhibited, and the frictional force between the ink ribbon 7 and the roller 11 or the pressing spring 12 also increases, and the ink ribbon 7 is no longer pulled out from the ribbon storage chamber 9 unless it is pulled out with a considerable force. There isn't. Therefore, if this ribbon cassette is set in the printer with the pressing lever 15 in the pushed state as shown in FIG. 5, the ink ribbon 7 pulled out to the outside at the front of the recess 1a in FIG. 1 will not be twisted. It is set in front of the print head 6 without any problem.

In the above embodiment, the mounting structure of the base 12a of the pressure spring 12 can be changed as appropriate. Further, even if the design of the roller 11 is changed to a pillar integral with the case 1, no problem will arise.

According to this invention, the ribbon cassette can be easily set in the printer without getting dirty with hands, and in particular, even if the pressing spring is formed of a thin spring material, a strong pressing force is generated by the wedge action of the protrusion against the column. The ink ribbon can be reliably locked by pressing the pressing lever.

[Brief explanation of drawings]

The drawings show an embodiment of the ribbon cassette according to the present invention, FIG. 1 is a sectional view showing its internal structure, FIG. 2 is a sectional view of the main part showing the feed roller, and FIG. FIG. 4 is an enlarged sectional view of the cross-sectional pressing lever, FIG. 4 is an enlarged perspective view of the pressing spring, and FIG.
The figure is a sectional view of a main part showing a state in which the press lever is pushed in. 1...Cassette case, 2...Feed roller, 6...Print head, 7...Ink ribbon, 9
... Ribbon storage chamber, 11 ... Roller (member located near the ink ribbon exit), 12 ... Pressure spring, 12b ... Protrusion, 15 ... Pressure lever, 19
...pillar.

Claims (1)

[Scope of Claim for Utility Model Registration] A ribbon cassette in which a portion of an endless ink ribbon is pulled out from a ribbon storage chamber of the cassette, and the ink ribbon is fed into the ribbon storage chamber by a feed roller, comprising: A pressing spring is provided which applies tension to the ink ribbon pulled out to the outside by pressing the ink ribbon pulled out from the ink ribbon against a member located near its outlet, and a pressing lever that engages with a part of the pressing spring is slid onto the cassette. The pressing spring is supported movably, and a protrusion is integrally formed on the pressing spring at a position near the member and directed toward the opposite side, and when the pressing lever is pushed in and the pressing spring is deformed, the pressing spring is moved. A ribbon cassette, characterized in that a pillar on which the protrusion abuts is formed on the cassette so as to face the protrusion.