JPH0114445Y2 - - 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 becomes twisted, and when the ink ribbon is tried to untwist, the tip of the ink becomes 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 bottom surface of the case 1, and a gear 5 is fixed to the protruding end thereof.When this ribbon cassette is set in a carriage (not shown) equipped with a print head 6, the carriage can be moved. At times, this gear 5 is rotationally driven, thereby rotating the feed roller 2 counterclockwise in FIG. As shown in the second figure, the ink ribbon 7 has black, blue, red, and yellow color bands 7b, 7c, and 7.
m, 7y, which are each transfer surface 2b, 2c,
2m and 2y via the pressure 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,
This 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 the third figure, the pressing lever 15 has a tongue 17 extending from its lower part, and a protrusion 17a at the end thereof.
can swing clockwise in FIG. 1 to a position where it abuts the end face of the partition wall 13. Furthermore, a protrusion 18 is formed on the inner surface of the pressing lever 15. 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.

When the ribbon cassette is grasped on both sides of the case 1 by hand in order to set it in the printer, the pressing lever 15 is pushed in with the fingertips against the spring force of the pressing spring 12 as shown in the fourth figure. Then the pressure spring 12
The base portion 12a of the ink ribbon 12a is pressed and bent using the protrusion 14 as a fulcrum, thereby increasing the force with which the pressing spring 12 presses the ink ribbon 7 against the roller 11.
This increase in pressing force inhibits the free rotation of the roller 11, and also increases the frictional force between the ink ribbon 7 and the roller 11. That is, the resistance force when the ink ribbon 7 is being pulled out from the ribbon storage chamber 9 increases, and the ink ribbon 7 can no longer be pulled out from the ribbon storage chamber 9 unless it is pulled out with considerable force. Therefore, the pressing lever 15
If this ribbon cassette is set in the printer while still being pushed in as shown in Fig. 4, the ink ribbon 7 exposed to the outside at the front of the recess 1a in Fig. 1 will print without being twisted. It is inserted in the front of the head 6.

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. Furthermore, the pressing lever 15 may also be placed relatively close to the roller 11, for example.

According to this invention, when setting the ribbon cassette in the printer, the ink ribbon can be locked by pushing the pressure lever, thereby allowing the ink ribbon to be smoothly inserted in front of the print head. It has great practical effects, such as being able to do it without getting your hands dirty.

[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 cross-sectional view of the press lever in cross section, and FIG. 4 is a cross-sectional view of the main part showing the press lever in a depressed state. 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 ... Pressing spring, 15 ... Pressing lever.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) In a ribbon cassette in which a part of the endless ink ribbon is pulled out from the ribbon storage chamber of the cassette, and the ink ribbon is fed into the ribbon storage chamber by a feed roller, the above-mentioned A pressing spring is provided which presses the ink ribbon pulled out from the ribbon storage chamber against a member located near its exit and applies tension to the ink ribbon pulled out to the outside. A pressing lever that engages with a part of the pressing spring is connected to the cassette. 1. A ribbon cassette, characterized in that the ribbon cassette is swingably supported, and when the pressing lever is pushed in, the pressing spring is deformed to increase its pressing force via the pressing lever. (2) The ribbon cassette according to claim 1, wherein the member is a roller rotatably supported by the cassette.