JPH04144755A - Ink tank - Google Patents

Abstract

PURPOSE:To prevent vaporization of ink by a method wherein a structure providing a communicating hole through which the open air communicates with an air chamber is formed in an upper cover is replaced by a structure providing the upper cover in which a ventilating hole the air chamber communicates with the open air and a ventilating groove are formed and a high barrier property seal member with which the ventilating hole and the ventilating groove are covered. CONSTITUTION:Ink 3 of a porous foam 2 in a tank case 1 is guided through a hollow needle 6 to a printing head 5. A printing head HD 5 effects recording of letters responding to recording information on a recording sheet on a platen 7. Ink consumed with the progress of recording of letters is fed from the porous foam 2 to the HD 5 through capillary phenomenon. In this case, the open air equivalent to the consumed ink 3 is guided to an air chamber 8 through communicating constitution of the air chamber, comprising a ventilating hole 9b, a ventilating groove 9c, and a seal 10, and the open air. Since the air chamber 8 has the constantly same pressure as that of the open air, the air chamber 8 is brought into a negative pressure state, the feed of the ink 3 to the HD 5 is in short supply, and excellent recording is carried out.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to an ink tank for an inkjet recording device that records characters, etc. on recording paper by ejecting ink droplets from a nozzle, and more specifically relates to Regarding the air chamber and outside air retaining communication configuration.

[Prior Art] Conventionally, in an inkjet recording device that records characters, etc. on recording paper by ejecting ink droplets from a nozzle, a communication structure between an air chamber in an ink tank and outside air is configured as shown in FIG. ing. A porous foam 2 is inserted into a tank case 1 and is impregnated with ink 3. A rubber plug 4 is attached to the bottom end of the tank case 1 to prevent ink 3 from leaking.
is provided. The print head 5 is provided with a hollow needle 6 for guiding the ink 3, and is inserted into the tank case 1 through the rubber stopper 4. The print head 5 is connected to the platen 7
Characters and the like are recorded on a recording paper (not shown) or the like according to the recording information. On the other hand, the upper M9
A lip 9d of the upper lid 9 is positioned so as to press down the foam 2, and an air chamber 8 is provided. Also, upper M9
is provided with a ventilation hole 9a that communicates the outside air with the air chamber 8. The ventilation hole 9a communicates the air chamber 8 with the outside air in order to prevent the air chamber 8 from becoming negative pressure as the ink 3 of the print head 5 is consumed and making it impossible to perform good recording.

[Problem to be solved by the invention] In the above-mentioned conventional example, the above! 9 is made of a plastic molded product, and the dimensions of the ventilation hole 9a are limited due to manufacturing constraints, so the hole diameter D; φ1! In case of I11, length L = 10m
m or less is common. In addition, in order to prevent evaporation of the ink 3 as much as possible and suppress changes in the ink components over time, it is preferable to have a diameter as small as possible and a length as long as possible. However, D
=φ1-1L:10 Rinho had a problem in that the change in ink components over time exceeded the specified value, making it impossible to obtain good print quality. Also, L=5
When the pressure is lower than ma+, there is also a problem in that the ink 3 leaks out from the vent hole 9a when the tank case 1 is dropped or the pressure is reduced. Furthermore, the height (external dimensions) of the ink tank has become large due to the ventilation hole.

Therefore, the present invention solves the above problems.
The purpose is to provide an ink tank that can maintain good print quality by providing a communication structure that prevents evaporation of the ink 3 as much as possible and suppresses changes in ink components over time. Another object of the present invention is to provide an ink tank with high reliability and safety by having a structure in which the ink 3 does not leak out from the vent hole 9a even when the ink tank is dropped or under reduced pressure. Also, the height of the ink tank (
To provide a compact ink tank with reduced external dimensions.

[Means for Solving the Problems] An ink tank of the present invention is an ink tank for an inkjet recording device that records characters, etc. on recording paper by ejecting ink droplets from a nozzle, and includes an air chamber provided at an upper end; It is characterized by comprising an upper lid provided with a ventilation hole and a ventilation groove that communicate the air chamber with the outside air, and a sealing member that covers the ventilation hole and the ventilation groove.

Further, the sealing member is provided so that the ventilation groove communicates with outside air.

Further, the sealing member is characterized in that it is made of a laminate film of aluminum foil, an aluminum vapor-deposited film, a plastic film with high gas barrier properties, or a combination thereof.

Further, the seal member is characterized in that printing is applied to the seal member so that it also serves as a caution label.

[Function] An air chamber provided at the top end of the ink tank, a top lid with a vent hole and a ventilation groove that communicate the air chamber with outside air, and a sealing member with high gas barrier properties that covers the vent hole and the ventilation groove. This increases the communication distance between the outside air and the air chamber, and with the addition of the gas barrier properties of the sealing member, we have been able to prevent ink evaporation as much as possible and suppress changes in ink components over time, resulting in a good design. Print quality can be maintained. Furthermore, since the communication distance between the outside air and the air chamber is made longer, ink will not leak out from the ventilation groove even if the ink tank is dropped or the pressure is reduced.

[Embodiment] FIGS. 1 and 2 are a schematic sectional view and a schematic top view showing an embodiment of the present invention. A porous foam 2 is inserted into a tank case 1 and is impregnated with ink 3. A rubber stopper 4 is provided at the lower end of the tank case 1 to prevent ink 3 from leaking. Ink 3 is in the print head 5.
A hollow needle 6 for guiding the water is provided, and is inserted into the tank case 1 through the rubber stopper 4. On the other hand, an upper lid 9 is provided at the upper part of the tank case 1, a rib 9d of the upper lid 9 is positioned so as to press down the foam 2, and an air chamber 8 is provided. Further, the upper M9 is provided with a ventilation hole 9b and a ventilation groove 9C. The air chamber 8 and the ventilation hole 9b communicate with each other, and the ventilation hole 9b and the ventilation groove 9C communicate with each other. The seal 10 covers the ventilation hole 9b and the ventilation groove 9c, and also covers the ventilation groove 9c.
A part of the pipe is attached so that it communicates with the outside air. Therefore, the air chamber 8 and the outside air communicate with each other, and the ventilation groove 9c forms a long ventilation hole. In this embodiment, the vent hole 9b has a hole diameter D1=φ1 to φ2.
m, length L1 = approximately 3111 m, width W = 0 for ventilation groove 9C
．． 8mm, groove depth H=0.6mm, length L2=20~
It is approximately 50a+m, and can be easily manufactured even if it is a plastic molded product. Also, by doing this, the ventilation hole 9
The hole diameter D1 of b may be set to φ1.5 or φ2.0, which also has the effect of facilitating the filling operation of the ink 3.

As shown in FIG. 3, the sticker 10 is a laminated film of aluminum foil, and consists of an adhesive layer 10a (thickness 0.1 to 0.2
mm), polyester layer 10b (thickness 30 to 100 μm)
), an aluminum foil layer 10c (thickness 1 to 30 μm), and a polyester layer 10d (thickness 30 to 100 μm),
It has a printing section 10e and doubles as a caution label.

Further, the seal 10 is not limited to a laminated film of aluminum foil, but may be an aluminum vapor-deposited film, a plastic film with high gas barrier properties (for example, a polyvinyl alcohol-based film, a polyvinylidene chloride-based film, a nylon-based film, etc.), or any of these films. It may be configured by a combination of.

Next, the operation of the above structure will be explained. The ink 3 in the porous foam 2 in the tank case 1 is guided to the print head 5 through the hollow needle 6 by a pump (not shown).

The print head 5 records characters and the like on a recording paper (not shown) on a platen 7 according to recording information. As characters and the like are recorded, the consumed ink is supplied from the porous foam 2 to the print head 5 by capillary action. At this time, outside air corresponding to the volume of the consumed ink 3 is guided to the air chamber 8 through the air chamber 8 and outside air communicating with each other by the ventilation hole 9b, the ventilation groove 9c, and the seal 10. In this way, since the air chamber 8 always has the same pressure as the outside air, there is no possibility that the air chamber 8 becomes negative pressure and the ink 3 is insufficiently supplied to the print head 5, thereby preventing good recording. or,
Even if the pressure in the air chamber 8 changes due to changes in the environmental temperature, the pressure is always maintained at the same level as the outside air, so there is no excess or deficiency in the supply of ink 3 to the print head 5, so good recording can be maintained. It is possible. In the communication structure between the air chamber 8 and the outside air, the ventilation hole 9b, the ventilation groove 9c, and the seal 10 form a long ventilation hole, so that the evaporation of the ink 3 can be suppressed as much as possible. The ink 3 will not leak out from the ventilation groove 9c even if it is dropped or under reduced pressure.

Further, since the seal 10 is a laminated film of aluminum foil, evaporation of the ink 3 can be suppressed as much as possible due to the high gas barrier properties of the aluminum foil. Further, since the sticker 10 is provided with a printing portion 10e and also serves as a caution label, the purpose can be achieved without increasing costs.

[Effects of the Invention] According to the present invention, the structure in which the upper lid is provided with a ventilation hole that communicates the outside air and the air chamber is replaced with the upper lid that is provided with the ventilation hole and the ventilation groove that connects the air chamber with the outside air, and the ventilation hole. By providing a seal member with a high gas barrier property that covers the ventilation groove, the communication distance between the outside air and the air chamber is increased, and the gas barrier of the seal member is increased.
In addition to this, it has been possible to prevent ink evaporation as much as possible and suppress changes in ink components over time, which has the effect of maintaining good print quality. In addition, the seal covering the ventilation holes and ventilation grooves allows for a longer communication distance between the outside air and the air chamber, and even if the ink tank falls or is under reduced pressure, ink will not leak out of the ventilation grooves, improving reliability and safety. It also has the effect of being able to measure In addition, the top cover had a convex ventilation hole that communicated the outside air with the air chamber, but now it has a top cover with ventilation holes and a ventilation groove, and a seal that covers the ventilation hole and the ventilation groove. This also has the effect of reducing the height (outer dimensions) of the ink tank.

[Brief explanation of the drawing]

FIG. 1 is a schematic sectional view of an embodiment of an ink tank of the present invention. FIG. 2 is a schematic top view of an embodiment of the ink tank of the present invention. FIG. 3 is a schematic sectional view of a seal of an embodiment of the ink tank of the present invention. FIG. 4 is a schematic cross-sectional view of a conventional ink tank. 1... Tank case 2... Form 3... Ink 4... Rubber stopper 5... Print head 6... Hollow needle 7... Platen 8... Air chamber 9... Top lid 9a... Ventilation hole 9b... Ventilation hole 9c... Ventilation groove 9d... Rib 10... Seal 10a... Adhesive layer 10b... Polyester layer Aluminum foil layer Polyester layer e Printed part and above

Claims (3)

[Claims] (1) In an ink tank of an inkjet recording device that performs recording on a recording medium by ejecting ink droplets from a nozzle, an air chamber provided at the upper end, a ventilation hole that communicates the air chamber with outside air, and a communication hole that communicates with the ventilation hole. An ink tank comprising: an upper lid provided with a ventilation groove; and a sealing member covering the ventilation hole and the ventilation groove. (2) The ink tank according to claim 1, wherein the sealing member is made of a laminate film of aluminum foil, a vapor-deposited aluminum film, a plastic film with high gas barrier properties, or a combination thereof. (3) The ink tank according to claim 1, wherein the seal member also serves as a caution label.