JPH0429878A - Ribbon mechanism in printer - Google Patents

Abstract

PURPOSE:To improve the running stability of an ink ribbon, prevent the breakage of the component parts of a ribbon mechanism part, and enhance the reliability of a printer by providing a ribbon guide between a ribbon separator and a sensor roller. CONSTITUTION:A ribbon guide 28 is provided with flanges 292, 293, 302, 303 which are respectively horizontally opposed to ribbon stoppers 231, 232, 241, 242 across an ink ribbon 4 to ensure the running position of the ink ribbon 4. In this manner, if the ink ribbon 4 comes into a fluttering state, the ribbon running position is corrected by the flanges 292, 293, 302, 303, and the ink ribbon 4 can be prevented from intruding between the ribbon stoppers 231, 232 and 241, 242 and a ribbon drive roller shaft 27 and prevented from being caught in between them. By providing the guide 28, the running stability of the ink ribbon 4 and an operability in loading the ink ribbon 4 are remarkably improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a ribbon mechanism that improves ribbon running stability in a shuttle-type dot line printer.

[Background of the invention]

Shuttle-type dot line printers reciprocate in the row direction a hammer bank containing multiple printing hammer heads arranged in rows, and print by transmitting the striking force of the printing hammers to the printing paper via an ink ribbon. In recent years, efforts have been made to particularly improve printing speed. FIG. 7 is a plan view for explaining the configuration of the shuttle type dot line printer. As shown in the figure, there is a hammer bank 1 in which a plurality of printing hammer heads (not shown) are mounted and housed, a shuttle mechanism section 2 that reciprocates the hammer bank 1 along the row direction, and a space between the printing paper 3 and the hammer bank 1. It is composed of an ink ribbon 4 arranged in the ink ribbon 4. ink ribbon 4
is a ribbon drive roller 51 composed of a pair of rollers.
．． 52, sensor roller 6, ribbon guide 7.8, and ribbon brake section 9, and is always fed in the direction of arrow B according to the six directions of rotation arrows of ribbon tribe rollers 51 and 52.

FIG. 3 is a plan view showing the mechanism around the ribbon drive rollers 51, 52 in more detail. The ink ribbon 4 is held between a pair of ribbon drive rollers 51 and 52, and as the ribbon drive rollers 51 and 52 rotate, the ink ribbon 4 is moved to a cassette 1.
It is folded into the case 22 as shown. At this time, one of the ribbon drive rollers 51 and 52 is on the driving side 5.
2 and the other side is a driven side 51, and the driven side ribbon drive roller 51 is generally connected to the driving side ribbon drive roller 52 by a compression spring 20 pushing an arm-shaped guide 19 supporting the ribbon drive roller 51, as shown in the figure. Being forced. The arm-shaped guide 19 is pivotally supported by a shaft 18 and can be rotated in the direction of the arrow, and is rotated when the ink ribbon 4 is replaced or the like. Reference numeral 21 denotes a wall on the opposite side of the arm-shaped guide 19 that holds the compression coil spring 20 therebetween.

FIG. 4 is a right side view of FIG. 3. As shown in the figure, the ribbon drive rollers 51 and 52 generally consist of several stages of rubber rollers, and are connected by gears 25 and 26 that are directly connected at the bottom. Note that this figure shows an example of three stages of rubber rollers. Ends 231.232.24 of ribbon cassette 22
1.242 is called a ribbon stopper and has a shape as shown in FIG. As shown in the figure, it is located between each rubber roller of ribbon drive rollers 51, 52.

The above is the ribbon mechanism of a conventional shuttle-type Doll-line printer, but with this configuration, as described below, prevention of the ink ribbon 4 from getting caught is insufficient, and loading of the ink ribbon 4 is difficult. There are drawbacks.

FIG. 5 is a plan view showing the state when the ink ribbon 4 enters between the ribosis 1 header 241 or 231 and the ribbon drive roller shaft 27 or 271 and the ink ribbon 4 is caught. The ink ribbon 4 approaches the end of its life as it is used. Then, when the ink ribbon 4 reaches the end of its lifespan, or when a specific location is frequently used and only the specific location approaches the end of its lifespan, the base fabric of the ink ribbon 4 is struck by the hammer head, causing damage to the base fabric and causing it to wave.

At this time, the conventional ribbon stripper 231.232.24
1.242, the guide of the ribbon drive roller 51.52 at the contact portion with the ink ribbon 4 is insufficient, and the ribbon stripper 2 is insufficiently guided in the ink ribbon 4 as shown by G in the figure.
41 and the ribbon drive roller shaft 27, resulting in a machine stoppage or damage to parts.

FIG. 6 is a plan view showing a state in which the driven ribbon drive roller 51 is opened in order to pass the ink ribbon 4 between the ribbon drive rollers 51 and 52 when replacing the ink ribbon 4. As shown in the figure, when replacing the ink ribbon 4, the ribbon drive roller 51- is opened by a lever (not shown), the lever is fixed by a stopper (not shown), and the ribbon drive roller 51 is stopped in the open state. At this time, the old ink ribbon 4 is taken out and then a new ink ribbon 4 is loaded, but the ribbon drive roller 52
The interval Q between the ribbon strippers 231 is only a few millimeters, and passing an ink ribbon made of nylon base fabric through the interval Q is a very difficult task.

[Purpose of the invention]

An object of the present invention is to eliminate the above-mentioned problems, ensure running stability of the ink ribbon of this type of printing device, improve printer reliability, and improve workability.

[Summary of the invention]

The present invention has focused on the fact that in order to improve the running stability of the ink ribbon, it is necessary to provide a guide to prevent the ink ribbon from getting caught in the ribbon drive roller, and in addition to the conventional ribbon stopper, a new ribbon stopper has been developed. A guide is provided, and the shape is devised to facilitate loading of the ink ribbon.

[Embodiments of the invention]

An embodiment according to the present invention will be described with reference to FIGS. 1 and 2.

Since it is the same as the prior art except for the parts detailed below, the description thereof will be omitted. Figure 1 shows guide 2 proposed by the present invention.
8 to ribbon stripper 231.232.241.242
2 is a plan view for explaining an example provided between the sensor roller 6 and the sensor roller 6, and FIG. 2 is a right side view of FIG. 1 viewed from H. The ribbon guide 28 has flanges 292, 293, 302, and 303 that sandwich the ink ribbon 4 and face the ribbon strippers 231, 232, 241, and 242 in the horizontal direction to ensure the running position of the ink ribbon 4. Even if the flange 2 becomes undulating,
92.293.302.303, the ribbon running position is corrected, and the ink ribbon 4 is moved to the ribbon stripper 231.
232, 241, 242 and the ribbon drive roller shafts 271 and 27, and the ink ribbon 4 can be prevented from being caught. Further, as shown in FIG. 2, an upwardly inclined flange 291.301 of the ribbon guide 28 is provided on the upper side of the ribbon drive roller 51.52. The flanges 291 and 301 are shaped so that they become lower from the outside to the center of the ribbon guide 28, so that when the ink ribbon 4 is loaded, the ink ribbon 4
is placed between the guides 291 and 301, the ink ribbon 4 can be easily loaded between the ribbon drive roller 52 and the ribbon stripper 231 along the guides 291 and 301. Providing this guide 28 greatly improves the running stability of the ink ribbon 4 and the workability during loading.

〔Effect of the invention〕

As explained above, according to the present invention, the ribbon guide is provided between the ribbon separator and the sensor roller, which improves the running stability of the ink ribbon, prevents damage to parts of the ribbon mechanism, and improves the reliability of the printer. can be achieved.

Furthermore, by adding an inclined flange to the upper part of the ribbon guide, it is possible to improve work efficiency when loading the ink ribbon.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing an embodiment of the ribbon feeding mechanism of the present invention, FIG. 2 is a right side view of FIG. 1, FIG. 3 is a plan view showing an example of the conventional ribbon feeding mechanism, and FIG. The figure is the right side view of Figure 3, and Figure 5 is the third view when the ink ribbon is nearing the end of its life.
FIG. 6 is a plan view of a conventional ribbon feeding mechanism during ink ribbon replacement, and FIG. 7 is a plan view of main parts of a conventional printing apparatus. In the figure, 1 is a hammer bank, 2 is a shuttle mechanism,
3 is a printing paper, 4 is an ink ribbon, 51.52 is a ribbon drive roller, 6 is a sensor roller, 7.8 is a ribbon guide, 9 is a ribbon brake section, 18 is a shaft, 19 is an arm guide, 20 is a compression spring, 21 is a wall, 22 is a ribbon cassette case, 231.232.241.242 is a ribbon stripper, 25.26 is a gear, 27.271 is a ribbon drive roller shaft, 28 is a guide, 291
．． 292.293.301.302.303 is a flange. ○ timesai 25211 H1') 亙 る 3u sai 4m koll 555 earth 7f ki sai lω

Claims (1)

[Scope of Claims] 1. A printer comprising an endless ink ribbon that is stored in a folded state in a ribbon cassette and moves between a hammer bank and printing paper, and a pair of ribbon drive rollers as a driving means for the ribbon. A ribbon drive that is close to the drive roller and is divided into several stages that face each other in the horizontal direction so as to sandwich the ink ribbon in order to maintain the running position of the ink ribbon on the side where the ink ribbon advances toward the ribbon drive roller. A ribbon mechanism for a printing device, comprising a ribbon guide having a flange located between rollers. 2. The ribbon mechanism of a printing device according to claim 1, wherein the ribbon guide is provided with an inclined guide to facilitate loading of the ink ribbon.