JPS6116868A - Ink cassette for ink dot printer - Google Patents

Abstract

PURPOSE:To suck ink smoothly to an ink guide from an ink tank by forming an inclination lowered toward the ink guide to the base in the ink tank. CONSTITUTION:With an ink cassette 20, a thick plate-shaped bottom cover 26 and a plate-shaped cover 27 covering the bottom cover 26 are fitted to a box- shaped tank cover 25 with no bottom from the lower section of the tank cover 25, and an ink tank 29 in which ink 28 is stored in formed into it. An inclined plane 36 lowered to a horizontal plane in the direction of an ink guide plate 30 is shaped to the bottom cover 26 at that time. Consequently, a sufficient quantity of ink 28 spreads extending over the upper section of the inclined plane 36 from an inlet for an ink path 35 even when the direction of the ink cassette 20 changes. Accordingly, air is difficult to collect between the ink tank 29 and an ink guide 33, and slits 34 are supplied smoothly with ink 28.

Description

TECHNICAL FIELD OF THE INVENTION The present invention relates to an ink cartridge 1- for supplying ink to the tip of a needle of an ink dot printer.

Technical Background and Problems of the Invention Conventionally, there has been an ink dot printer that forms an ink film on the tip of a needle, moves the needle back and forth, and brings the ink-covered tip into contact with recording paper to perform printing. Exists. Examples of such are shown in FIGS. 6 and 7. The plurality of needles 1 are connected to the head body 2
The rear end is selectively driven by a drive unit 3 to reciprocate in the axial direction. An ink cassette 5 for supplying ink 4 to the tip of the needle 1 is detachably attached to the head body 2. This ink cassette 5 is formed by integrating an ink tank 6 storing a certain amount of ink 4 and an ink guide 8 having an ink passage 7 extending from the lower end of the ink tank 6. A slit 9 communicating with the ink passage 7 is formed. Here, the ink 4 in the ink tank 6 is sucked into the ink passage 7 by capillary action, and is further held in the slit 9 by surface tension.

When the ink cassette 5 is attached to the head body 2, the tip of the needle 1 is placed in the slit 9 and receives the ink 4. Here, printing is performed by selectively driving the needle 1 using the drive unit 3 and bringing the tip of the needle into contact with recording paper (not shown).

On the other hand, when installing the ink cassette 5 to the head body 2,
Due to the change in the orientation of the ink cassette 5, the ink tank 6
Air is trapped between the ink passage 7 of the ink guide 8, and
Air bubbles 10 may occur. Empty bubble at this position
When O occurs, the pressure within the ink tank 6 becomes balanced and the ink 4 is no longer sucked into the ink guide 8, resulting in a disadvantage that the ink 4 cannot be supplied to the tip of the needle 1.

OBJECTS OF THE INVENTION The present invention has been made in view of the above points, and an object of the present invention is to provide an ink cassette for an ink dot printer that can smoothly suck ink from an ink tank to an ink guide.

Summary of the Invention The present invention integrally forms an ink tank that stores a certain amount of ink and an ink guide that has a slit that communicates with the ink tank and projects downward. Because of the downward slope, even if the orientation of the ink cartridge 1- changes, a sufficient amount of ink will be distributed from the entrance of the ink guide to the sloped bottom surface, and there will be no empty space in the communication area between the ink tank and the ink guide. The structure is such that no bubbles are generated and ink can be smoothly drawn into the ink guide.

Embodiment of the Invention An embodiment of the present invention will be described with reference to FIGS. 1 to 5. FIG. First, the ink cassette 20 is attached to a head main body 21 to constitute a print head 22. The head main body 21 slidably holds a plurality of needles 23 therein, and these needles 23 are arranged in a vertical line in a horizontal state. A drive unit 24 is provided at the rear end of the needles 23 to drive the needles 23 to reciprocate.

Next, the above-mentioned Infcasera 1-20 will be explained. This ink cassette 20 has a tank cover 25 in the form of a bottomless case, and a bottom cover 26 in the form of a thick plate from below.
A flat plate-like cover 27 is fitted therein, and an ink tank 29 storing ink 28 is formed inside.

The tank cover 25 and the bottom cover 26 are integrally formed with ink guide plates 30 that extend downward and are in close contact with each other. Contacting ink groove 3
2 are provided in alignment with each other. Here, an ink guide 33 is formed by two ink guide plates 30, and this ink guide 33 has a slit 34 formed by two needle holes 31 and an ink passage 35 formed by two ink grooves 32 communicating with the slit 34. It is formed.

Further, the bottom lid 26 is sloped to be lower with respect to the horizontal plane in the direction of the ink guide plate 30, and the sloped surface serves as a sloped surface 36.

An ink groove 32 extending from the ink guide plate 30 is carved into this inclined surface 36, and an air supply hole 37 is provided at one lower end of the inclined surface 36. An air supply groove 38 communicating with the outside is provided on the bottom surface of the bottom cover 26, and the air supply hole 37 communicates with this air supply groove 38. Furthermore, porous water absorbing portions 39 are provided on both sides of the air supply groove 38. Note that the air supply holes 37 are set to a width where capillary action occurs, and the air supply grooves 38 are set to a width where capillary action does not occur.

Therefore, the bottom surface inside the ink tank 29 has an inclined surface 3 that is sloped so that the inlet direction of the ink passage 35 is gradually lowered.
It is attached by 6. Further, with the ink cassette 20 attached to the head body 21, the tip of the needle 23 is placed in the slit 34, so that a gap 40 is created between the ink cassette 20 and the head body 21.

In such a configuration, the ink 28 in the ink tank 29 is sucked into the ink passage 35 by capillary action,
The ink is held in the slit 34 by surface tension to form an ink [41]. Here, this ink film 41 causes the needle 23 to
Ink 28 flows around the tips of the needles 23, and by selectively driving the needles 23 with a drive unit 24, printing is performed on a recording sheet (not shown). As the printing operation progresses, the ink 28 in the slit 34 is consumed and gradually decreases.
The sink 8 is supplied from the ink tank 29 to the slit 34 through the ink passage 35.

At this time, an amount of air must be introduced into the ink cassette 20 in an amount commensurate with the amount of ink 28 consumed. In this embodiment, external air flows in from the air supply groove 38, and this air is introduced into the ink cassette 20 as air bubbles through the air supply hole 37. Note that during printing, a shock is applied to the print head 22 due to its operation, and the air supply hole 3
There is a possibility that the ink 28 leaks from the ink 7, but in this case, it is quickly absorbed by the water absorbing portions 39 provided on both sides of the air supply groove 38.

On the other hand, in this embodiment, on the bottom inside the ink tank 29,
The ink passage 1835 is sloped so that the inlet direction thereof is gradually lowered by the sloped surface 36.

As a result, even if the orientation of the ink cassette 20 changes, a sufficient amount of ink 28 will spread from the entrance of the ink passage 35 to above the inclined surface 36. Therefore, when installing one ink cassette 20 to the head main body 21, air stagnation between the ink tank 29 and the ink guide 33 due to a change in the orientation of the ink cassette 20 is less likely to occur, and the ink 28 is not supplied to the slit 34. , carried out by Moose. Therefore, the responsiveness of the ink 28 supply to the ink 28 in the slit 34, which is consumed in the printing operation, is improved, and stable printing can be achieved.

Effects of the Invention In the present invention, as described in -1- below, the bottom surface of the ink tank is sloped downward toward the ink guide 1.

Even if the direction toward the ink cartridge 1 changes, a sufficient amount of ink will be distributed from the inlet of the ink guide to the upper part of the slanted bottom surface, and no air bubbles will be generated in the communication area between the ink tank and the ink guide, and the ink will not reach the ink guide. Ink can be suctioned smoothly, therefore, ink can be quickly supplied to the slits, and the responsiveness of ink supply to the slits according to ink consumption is improved.

This has effects such as being able to provide stable printing.

[Brief explanation of the drawing]

Fig. 1 is a 17° vertical cross-sectional side view of a print head showing an embodiment of the present invention, Fig. 2 is a perspective view thereof, Fig. 3 is an exploded perspective view of the ink power set 1-, and Fig. 4 is a bottom cover of the print head. FIG. 5 is a plan view, FIG. 5 is a side view thereof, FIG. 6 is a perspective view of a print head showing a conventional example, and FIG. 7 is a longitudinal sectional side view showing the shape of an ink cassette. 20... Ink cartridge 1-129... Ink tank, 33... Ink guide, 34... Slit applicant Tokyo Electric Co., Ltd.

Claims (1)

[Claims] An ink tank for storing a certain amount of ink is provided, an ink guide having a slit communicating with the ink tank and projecting downward is provided integrally with the ink tank, and an ink guide is provided on the bottom surface of the ink tank. An ink cassette for ink dot printers that features a downward slope.