JPH089256B2 - Ink ribbon cassette - Google Patents

Description

The present invention relates to an ink replenishing type ink ribbon cassette in a serial printer.

[Prior Art] The ink ribbon device is stored in a cassette in consideration of facilitating the mounting of the ink ribbon, eliminating stains on hands and the peripheral portion of the device when mounting the ink ribbon, and downsizing. There is an ink ribbon cassette that is mounted on a carriage for use.

On the other hand, the life of the ink ribbon is generally determined by the amount of ink impregnated in the ink ribbon, and the life of the ink ribbon base cloth itself is usually much longer.

Therefore, there has been proposed an ink ribbon cassette including an ink replenishing means for replenishing the ink ribbon with an appropriate amount of ink in order to prolong the life of the ink ribbon.

FIG. 5 is a plan view of such an ink ribbon cassette with a lid removed, and FIG. 6 is an explanatory view of an ink replenishing section, which will be described below with reference to these drawings.

In the figure, reference numeral 1 denotes an endless Mobius-shaped ink ribbon, which is housed in a ribbon cassette 2 and only part of which is exposed to the outside.

Reference numeral 3 is a ribbon storage portion of the ribbon cassette 2, reference numerals 4a and 4b are ribbon guide portions, and the ink ribbon 1 moves in the arrow direction.

Reference numeral 5 denotes a drive roller, which is disposed at the entrance of the ribbon storage section 2 and is supported by the drive roller fixing member 6.

A driven roller 7 is in contact with the drive roller 5 and is supported by a driven roller support member 8.
An ink replenishing section 9 is in contact with the driven roller 7,
The ink replenishing section 9 is connected to the ink replenishing body 10 to suck up the ink of the ink replenishing body 10 by a capillary phenomenon and supply it to the driven roller 7. Reference numeral 11 is a spring for pressing the driven roller 7 against the drive roller 5.

With the above configuration, the ink ribbon 1 sandwiched between the drive roller 5 and the driven roller 7 is circulated and drawn into the ribbon storage portion 3 by the drive of the drive roller 5 and stored in a folded state.

On the other hand, the pulled out ink ribbon 1 has a ribbon guide portion 4a.
The ribbon guide section
After passing through 4b, it is circulated and drawn into the ribbon storage portion 3 as described above.

When the ink is drawn in, the ink that has exuded from the ink replenishing section 9 that is in contact with the driven roller 7 is supplied to the driven roller 7, and is transferred and replenished to the ink ribbon 1.

[Problems to be Solved by the Invention]

In the above-mentioned conventional techniques, the mutual relationship between the viscosity of the ink previously impregnated in the ink ribbon and the viscosity of the ink impregnated in the ink replenisher is not specified.

For example, the viscosity of the ink impregnated in the ink ribbon in a system in which the ink ribbon is not replenished with ink increases the usage rate of the ink due to high printing efficiency in the graphic printer, and improves the ink supplyability of the ink ribbon. Therefore, the viscosity of the ink is set low, and when it is necessary to maintain the printing quality as in the kanji printer, the viscosity of the ink of the ink ribbon is set higher than the viscosity of the ink in the graphic printer.

In this way, the viscosity of the ink is an important factor for improving the printing quality, but in the case of the ink replenishment method, the viscosity of the ink impregnated in the ink replenisher is more than the viscosity of the ink that is preliminarily impregnated in the ink ribbon. Is high, the amount of ink replenished from the ink replenisher is not sufficient with respect to the amount of ink impregnated in the ink ribbon,
There is a problem that the print quality and print density decrease due to lack of ink.

That is, the performance of ink replenishment from the ink replenisher depends on the viscosity of the ink, and the lower the viscosity, the better the ink replenishment.

Further, when the viscosity of the ink impregnated in the ink replenisher is lower than the viscosity of the ink impregnated in the ink ribbon, the situation is the reverse of the above, and the ink replenishment from the ink replenisher becomes too much, and the printing becomes difficult. There is a problem of bleeding and stains.

Since the relationship between the viscosity of the ink previously impregnated in the ink ribbon and the viscosity of the ink impregnated in the ink replenisher is uncertain, the print quality, print density drop, print bleed, stain, etc. Will occur.

[Means for solving the problem]

The present invention has a ribbon storage portion for folding and storing an ink ribbon, and disposing a driving roller and a driven roller for taking in the ink ribbon at the ribbon storage portion inlet,
In an ink ribbon cassette provided with an ink replenishing unit that comes into contact with the driven roller and an ink replenisher that supplies ink to the ink replenishing unit, the viscosity of the ink with which the ink ribbon is preliminarily impregnated is made higher than the viscosity of the ink of the ink replenisher. Is characterized by.

[Action]

According to the above configuration, the ink of the ink replenisher can be satisfactorily transferred to the ink ribbon, and the desired print quality can be ensured.

〔Example〕

 Embodiments of the present invention will be described below with reference to the drawings.

The ink ribbon cassette of the ink ribbon used in the following description is the same as that described in the above-mentioned prior art, and includes an endless ink ribbon 1, a ribbon storage section 3 for storing the ink ribbon 1 by folding, and an ink ribbon 1. Since it has a driving roller 5 and a driven roller 7 for taking the ink into the ribbon storage portion 3, an ink replenishing portion 9 that abuts on the driven roller 7, an ink replenisher 10 that supplies ink to the ink replenishing portion 9, and the like. Detailed description is omitted.

The above-mentioned ink ribbon cassette is not limited to this, and the present invention is similarly applied to other ink ribbon cassettes configured to transfer the ink from the ink replenisher.

The relationship between the ink viscosity and the ink consumption of the ink ribbon is as shown in FIG. 1, and it can be seen that the ink consumption depends on the ink viscosity and the printing efficiency.

The relationship between the number of prints and the amount of ink consumption is as shown in FIG. 2, and in the case of only the ink ribbon which is not the ink replenishment method, this ratio depends on the amount of ink impregnated in the ink ribbon and the length of the ink ribbon. Is determined, and the amount of ink consumption varies depending on the size of the printing efficiency, and the relationship is almost unchanged and is defined by a linear function.

However, according to the ink replenishment method, when the printing efficiency is high, the amount of ink used in the initial stage is large, so the ink consumption from the ink ribbon and the ink replenisher already impregnated with the ink is large. It can be seen that since the ink amount of the ink ribbon and the ink replenisher is small, the amount of ink that can be supplied is small in the latter half of printing and the ink consumption is small.

On the contrary, when the printing efficiency is low, the amount of ink used in the initial stage is small, so the ink consumption from the ink ribbon and the ink replenisher is small, and the ink amount of the ink ribbon and the ink replenisher is secured. It can be seen that since there is ink that can be supplied until the latter half of printing, there is little drop in ink consumption.

Next, the relationship between the number of prints and the print density depending on the viscosity of the ink of the ink replenisher is as shown in FIG.

If the viscosity of the ink of the ink replenisher is high, the
As shown in the figure, the print density decreases in the initial stage due to the relationship between the number of prints and the degree of ink supply. Conversely, when the viscosity of the ink in the ink replenisher is low, the print density can maintain the initial value up to a certain print count. I know that I can do it.

From the above, it can be seen that even if the ink replenisher is impregnated with the ink having the same viscosity as the ink previously impregnated into the ink ribbon, the ink cannot be replenished sufficiently. Therefore, the viscosity of the ink that allows good ink replenishment and maintains the printing quality will be described below.

Normally, ink has various printing patterns such as character printing, graphic printing, ruled line printing, etc., and the viscosity of the ink pre-impregnated in the ink ribbon is such that the printing quality as a result of printing with these printing patterns is satisfied. It has been decided.

Since the ink of the ink replenisher is transferred to the ink ribbon, it must be at least lower than the viscosity of the ink that has been previously impregnated in the ink ribbon. This is because the viscosity of the ink that has been impregnated in the ink ribbon in advance is suitable for the desired print quality, as described above. However, if the viscosity of the ink of the ink replenisher is higher than the viscosity of the ink that has been impregnated in the ink ribbon in advance, the ink replenishment is inferior to the ink consumption efficiency of the ink ribbon, resulting in a decrease in the print density.

On the other hand, when the viscosity of the ink of the ink replenisher is too lower than the viscosity of the ink that has been impregnated in the ink ribbon in advance, the ink is excessively transferred to the ink ribbon and the print density increases,
Print bleeding, print stains, etc. occur.

Therefore, as described above, the viscosity of the ink previously impregnated into the ink ribbon must be larger than the viscosity of the ink of the ink replenisher, and according to the experiments by the inventor, the difference in viscosity is optimally around 200 cp. It was Further, as a result of experiments, it was found that when the viscosity difference was within 300 cp or within 50%, the ink of the ink replenisher was satisfactorily transferred to the ink ribbon and the desired print quality was obtained.

〔The invention's effect〕

According to the present invention described in detail above, it has a ribbon storage portion for folding and storing an ink ribbon, and a driving roller and a driven roller for taking in the ink ribbon are arranged at the entrance of the ribbon storage portion, and the driven roller contacts the driven roller. In an ink ribbon cassette provided with an ink replenishing unit in contact and an ink replenisher for supplying ink to the ink replenishing unit,
By making the viscosity of the ink with which the ink ribbon is impregnated in advance higher than the viscosity of the ink of the ink replenisher, there is an effect that the ink of the ink replenisher can be satisfactorily transferred to the ink ribbon, and the printing quality is also desired. It has the effect of obtaining quality.

[Brief description of drawings]

FIG. 1 is a graph showing ink viscosity and ink consumption,
Fig. 3 is a graph showing the number of prints and ink consumption, Fig. 3 is a graph showing the number of prints and print density, Fig. 4 is a graph showing the number of prints and ink supply, and Fig. 5 is a cover of the ink ribbon cassette. FIG. 6 is a plan view of the state, and FIG. 6 is an explanatory view of the ink replenishing section. 1 ... Ink ribbon 3 ... Ribbon storage 5 ... Drive roller 7 ... Followed roller 9 ... Ink replenishment unit 10 ... Ink replenisher

Claims (1)

[Claims] 1. A ribbon storage part for folding and storing an ink ribbon, wherein a drive roller and a driven roller for taking in the ink ribbon are arranged at the entrance of the ribbon storage part.
In an ink ribbon cassette provided with an ink replenishing unit that comes into contact with the driven roller and an ink replenisher that supplies ink to the ink replenishing unit, the viscosity of the ink with which the ink ribbon is preliminarily impregnated is made higher than the viscosity of the ink of the ink replenisher. Ink ribbon cassette featuring.