JPH06183023A - Ink cartridge and ink jet recorder - Google Patents

Abstract

PURPOSE:To obtain a small and inexpensive ink cartridge and ink jet recorder in which ink is used efficiently by forming an ink bag of a flexible material, placing a pair of plate members coupled through a spring member in the ink bag, and allowing intrusion of outer air into the ink bag when the ink supply pressure reaches a predetermined negative level. CONSTITUTION:In an ink cartridge 6 being employed in an ink jet recorder where ink is introduced from an ink cartridge to a recording head thence delivered through a nozzle toward a recording member, a flexible bag 1 for containing ink is placed in the ink cartridge 6 and a pair of rigid plate members 213, 214 coupled through a leaf spring 3 is contained in the bag 1. This structure allows generation of negative pressure in the tank through a simple structure and realizes a small and inexpensive ink cartridge having high ink use efficiency.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet recording apparatus, and more particularly to an ink cartridge for storing and holding ink and supplying the ink to a recording head.

[0002]

2. Description of the Related Art Conventionally, an ink jet recording apparatus (see FIG.
In order to prevent ink leakage from the ejection port of the recording head by maintaining the performance of the inkjet recording head and canceling the positive pressure due to the water head difference of the ink cartridge, see the ink surface of the ink cartridge rather than the ejection port. The ink supply pressure applied to the recording head is maintained at a predetermined negative pressure by arranging the ink at a low position.

However, according to this method, there is a restriction on the arrangement position of the ink tank with respect to the ink jet recording head, and in the serial scan type recording apparatus, it is difficult to arrange the tank especially on the carriage, and it is difficult to arrange the ink droplets. Since the ejection direction of is also limited, it is impossible to satisfy all situations of the printing posture. Therefore, as a means for solving the above restriction, it has been proposed to provide a means for generating a negative pressure in the ink container itself.

For example, one of the methods is disclosed in JP-A-56-67.
No. 269, the cross section of the ink tank is shown in FIG.
The configurations are as shown in (a), (b), and (c).

FIG. 13A shows a system in which the side wall 52 and the upper and lower walls 58 of the ink tank have different thicknesses. The internal pressure is maintained by the elastic force of the side wall 52, the side wall 52 is made thinner than the upper and lower walls of the central portion, and the flat ink tank is uniformly deformed by the elastic force of the side wall 52 to consume the ink.

In FIG. 13B, the side wall of the ink tank is formed into a bellows shape 54, and the balance of pressure is maintained by the elasticity of the bellows portion.

FIG. 13 (c) shows an ink tank 55 having a uniform wall thickness, in which a spring member 56 is arranged to generate a negative pressure.

In FIG. 14, an ink bag 60 is provided inside the ink tank 59, the ink bag 60 is held in the ink tank 59 by an elastic body 61, and a negative pressure is generated at the ink outlet 62 by the tensile force of the elastic body 61. It is what makes me.

However, the above conventional example has the following problems.

In FIG. 13A, the thickness and shape of the side wall 52,
Since the negative pressure characteristic of the ink tank is determined by the material, it is necessary to optimize the shape (thickness material, etc.) of the side wall 52 in order to improve the negative pressure characteristic of the ink tank and the ink use efficiency. However, it is difficult to improve the negative pressure characteristics and increase the ink use efficiency because there is a limit in terms of wall thickness and shape in designing and manufacturing, although it is necessary to minimize the above.

Also in FIG. 13B, the negative pressure characteristic of the ink tank is determined by the shape of the bellows 54 (thickness material, etc.) as in FIG.
However, since it is difficult to make the bellows 54 uniform in shape (uniform in wall thickness) and thin in manufacturing,
It was difficult to improve the ink use efficiency and stabilize the negative pressure characteristic. Further, there is a drawback that the amount of residual ink increases because the bellows cannot be brought into close contact with each other at the end of use of the ink.

In FIG. 13 (c), since the spring material 56 is in close contact with each other at the end of ink use, the tank 55 is
If the material is made flexible, the tank 55 will finally come into close contact, and the residual ink amount can be reduced. However, since the tank 55 is flexible during the initial ink filling, it is difficult to spread the spring force of the spring material 56 over the entire tank 55, and the initial ink filling amount is extremely small.
Further, in order to increase the initial ink filling amount, that is, in order to spread the spring force of the spring material 56 over the entire tank 55, the tank 55 needs to have a certain degree of rigidity. Since 55 is less likely to be crushed and cannot be adhered, the negative pressure is increased and the residual ink amount is increased.

Further, in FIG. 14, a negative pressure is generated in the ink inside the bag 60 by the spring force of the spring 61 between the ink bag 60 and the tank 59. In this method, the spring 61 needs a certain length in the initial state. Therefore the bag 60
Since there is a considerable dead volume that cannot be filled with ink between the tank and the tank 59, it is difficult to miniaturize the tank.

As with all ink containers, there is concern that residual ink may cause environmental pollution when the ink container is discarded.

[0015]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object thereof is to generate a negative pressure inside a tank with a simple structure and to achieve high ink use efficiency. It is to provide an inexpensive and small ink cartridge.

Further, according to the present invention, the ink supply pressure can be maintained at a predetermined negative pressure amount so that normal recording can be performed, and the ink use efficiency is almost 100%.
It is to provide an ink jet recording apparatus which is free from environmental pollution due to residual ink.

[0017]

In order to achieve the above object, in the present invention, an ink jet recording head for recording ink on a recording material by ejecting ink using an energy converter, and a sealed ink bag. An ink jet recording apparatus comprising an ink cartridge including the ink jet recording head and a supply means for connecting the ink jet recording head and the ink cartridge, the ink cartridge having a flexible bag for accommodating ink, By sandwiching a pair of rigid plate-shaped members inside the flexible bag and a spring member between the pair of plate-shaped members, a negative pressure is generated inside the flexible bag. The air is introduced from the outside into the ink bag when the ink supply pressure reaches a predetermined negative pressure amount.

[0018]

The ink bag is made of a flexible material, and a pair of rigid plate-like members and a spring member are arranged between them to maintain a negative pressure in the ink bag by a spring force. The negative pressure amount of the ink supply pressure increases due to the ink consumption, and when the predetermined negative pressure amount is detected, a hole is opened and air is taken into the ink bag to absorb the increased negative pressure. . As a result, the negative pressure amount of the ink supply pressure is relaxed, and most of the ink can be consumed.

[0019]

Embodiments of the cartridge of the present invention will now be described in detail with reference to the drawings.

FIG. 1 shows an ink cartridge according to an embodiment of the present invention, where 1 is a flexible ink bag for containing ink, 2 is an opening for taking out the ink from the ink bag 1, A joint for holding and sealing the ink bag 1, 3 is a spring member for generating a negative pressure inside the ink bag 1, 4 is a spring force of the spring member 3 acting on the entire ink bag 1, and the spring member 3 A pair of plate-like members sandwiching the spring member 3 for holding the ink, 5 is a plug for sealing the ink extraction opening of the joint 2, and 6 is the ink bag 1 connected to the joint 2. Is an ink cartridge body, and 7 is an ink cartridge lid.

In the above structure, the ink is contained in the flexible ink bag 1, and since the ink needs to be shielded from the outside air, the ink bag is a non-air permeable material, for example, polyethylene / polyethylene terephthalate, polyethylene from the ink side. / Polyvinylidene chloride / nylon polyethylene / nylon, etc. are used. And this ink bag 1
As shown in FIG. 2, when the ink is overfilled, the entire volume increases up to a region where the spring force of the spring member 3 does not act as shown by the dotted line. Then, as the ink is used to decrease from this state, the spring force of the spring member 3 acts on the ink bag by the pair of plate-shaped members to generate a negative pressure in the ink. Finally, the flexible ink bag 1 is crushed and the negative pressure rises sharply to make ejection impossible.

Therefore, in the above structure, the pair of plate-like members 4 are thin and have a sufficient thickness in order to sufficiently apply the spring force to the ink bag and to secure a sufficient ink injection volume in the ink bag. It is necessary to have sufficient rigidity. For example, SUS plate, resin containing glass fiber, PES, PEEK, etc. are used, and the flexible ink bag 1 is shown in FIG. 2 by the pair of rigid plate-like members 4 and the spring member 3 sandwiched between them. As shown, the flat state (A) can be formed into a substantially rectangular parallelepiped shape (B), and a sufficient ink injection amount can be secured.

As the spring member 3, a coil spring shown in FIG. 4A or an elastic body shown in FIG. 4B, such as polyurethane foam, is used.

FIG. 3 is a view showing how a pair of plate-like members 4 and spring members 3 are housed in the bag 1 of this embodiment,
The spring member 3 is inserted from the opening of the bag 1 in a state of being sandwiched between the pair of plate-shaped members 4 and stored.

FIG. 5 is a cross section of the ink bag 1 showing a preferable structure for further increasing the efficiency of use of the ink in the ink bag.

In this case, the spring member 3 is a conical coil spring, and since the contact height of the spring is almost equal to the wire diameter of the spring, as shown in FIG. Since the contact height of the spring does not hinder the ink bag 1 to be in close contact, the amount of remaining ink can be reduced and the efficiency of ink use can be improved.

Another embodiment of the present invention will be described with reference to the drawings.

FIG. 6 shows a case where a pair of plate-like members in a flexible ink bag and a spring member between the pair of plate-like members are integrally formed of the same material. The plate-shaped member 8 is, for example, a rigid SUS plate, is pressed as shown in FIG. 6A, is bent as shown in FIG. 6B, and is housed in the flexible bag 1.

At this time, the plate member 8 has a thickness t and a width l,
The spring constant of the plate member 8 can be determined by changing the bending angle. That is, the material of the flexible bag 1,
The plate-shaped member 8 can be formed according to the size and the like. According to this method, since the pair of plate-shaped members and the spring member can be formed by one member, the number of parts can be reduced, the number of assembling steps can be reduced, and a significant cost reduction can be realized.

Another embodiment of the present invention will be described with reference to the drawings.

FIG. 7 shows a method of fixing one of the outer side surfaces of the flexible ink bag to the inner wall surface of the ink cartridge. As shown in FIG. 7A, one outer surface of the flexible ink bag which is spread by the plate member 4 and the inner wall surface of the ink cartridge 6 are fixed by an adhesive layer 9.
For the adhesive layer 9, an adhesive tape or an adhesive is used.

In this system, for example, when the ink cartridge is mounted on the carriage and reciprocated in the direction of arrow A, the swinging of the flexible ink bag 1 can be considerably suppressed. Particularly, as the ink in the flexible ink bag 1 is consumed, the space between the ink cartridge 6 and the flexible ink bag 1 becomes large, so that the effect of suppressing the swing of the ink bag 1 becomes large.

Therefore, it is possible to prevent the ejection failure due to the swing of the ink bag 1 and the damage of the ink bag 1.

Further, even when the ink cartridge is fixed to the printer, it is possible to prevent the ink bag 1 from swinging during transportation, so that ink leakage due to damage to the flexible ink bag 1 can be prevented.

However, in the case of the above-described embodiment, when used in the ink jet recording apparatus, the repulsive force of the spring member in the ink bag becomes stronger as the ink is consumed, so that the ink bag is made stronger. In some cases, the negative pressure in the ink bag gradually increases due to the incomplete reduction of the ink, and the supply of the ink may be stopped before the ink is completely used up.

Therefore, further examples of the ink jet recording apparatus of the present invention will be described.

FIG. 8 shows a state in which the ink cartridge 6 and the recording head 10 are connected by a supply member 211 and face a platen 100 which supports a recording medium (not shown). The recording head 10 is provided with an ejection port in the platen direction, and a positive pressure is applied to the ejection port due to the head difference of the ink cartridge. The ink bag 1 inside the ink cartridge 6 is for the purpose of canceling the positive pressure.
Includes a spring member 3 inside the flexible member 210. Further, the spring member 3 includes a plate 213 with a protrusion and a plate 214 with a hole.
It is sandwiched between, and is arranged so that the protrusion fits in the hole. The flexible member 210 is attached to the opening member 215 having a rubber plug 217 by means such as welding, adhesion, and pressure bonding. Then, there is an opening in the flexible member 210 at a position corresponding to the hole of the holed plate 214, and a thin plate 216 is joined so as to cover the opening.

The structure near the thin plate 216 will be described with reference to FIG. (A) is a plan view of the ink bag 4,
(B) is an enlarged cross-sectional view of the vicinity of the thin plate 216. In this embodiment, the flexible member 210 and the thin plate 216 are joined by heat welding. The material of the flexible member 210 is PE / nylon / PE, PE / Al / PE, PE / PE considering gas barrier property.
T / PE, PE / Eval * / PE, PE / vinylidene chloride / PE, etc. are mentioned, and each layer having a thickness of 30 μm or less is suitable (Eval: registered trademark of ethylene / vinyl alcohol copolymer resin; Kuraray Co., Ltd.). The material of the thin plate 216 is PE / PET (100 μm), PE / SU from the flexible member side.
A material having a restoring force such as S (100 μm) is suitable.

The margin for welding the flexible member 210 and the thin plate 216 is provided with a wide portion such as 216a in (A) and a narrow portion such as 216b.

The operation will be described with reference to FIG. (A) shows the initial state, the plate with projection 213 and the plate with hole 214
The flexible member 210 and the thin plate 216 are thermally welded to each other. The spring member 3 is compressed by the atmospheric pressure as the ink is consumed, but the negative pressure in the ink storage unit becomes high. Then, when the state becomes (b), the plate 21 with protrusions
The thin plate 216 is peeled off from the flexible member 210 by the protrusions of No. 3. The peeling position is the 216b part where the bonding strength is weak,
The thin plate 216 has the property of a leaf spring having a fixed portion 216a. At this time, air enters the ink bag from the peeling portion of the thin plate 216, and the spring member 3 is restored as in the state (c). As a result, the negative pressure is relieved. In the state (c), the thin plate 216 and the flexible member 210 are in close contact with each other, and ink meniscus holding force therebetween prevents ink leakage. However, the ink liquid level in the state (c) is lower than that of the air intake portion (peeling portion of the thin plate 216), and the recording head 1
When the position is equal to or less than 0, there is no problem in performance even if the air intake section is always in the atmosphere communication after the state (b).

Another embodiment of the ink jet recording apparatus of the present invention will be described.

In FIG. 11, the recording head 1 having an ink cartridge 6 and a first nozzle 60 for ejecting ink for recording is connected by a supply member 211 and faces a platen 100 for supporting a recording medium (not shown). It shows how it was done. A state in which a positive pressure is applied to the ejection port of the recording head 10 due to the difference in the heads of the ink cartridge and the recording head is shown. For the purpose of canceling the positive pressure, the ink bag 1 inside the ink cartridge 3 has a flexible member 21.
0 has a spring member 3 inside. Flexible member 210
Is attached to the opening member 215 having a rubber plug 217 by means of welding, adhesion, pressure bonding, or the like. The recording head 10 includes a second nozzle 61 in addition to the first nozzle 60.
have. The second nozzle 61 is connected to the ink bag 1 by a pipe 212. The second nozzle 61 has a larger cross-sectional area than the first nozzle 60.
Is formed so that the meniscus holding force of is equal to Pmax.

The operation will be described.

As the ink is consumed, the spring member 3 is compressed, the negative pressure in the ink bag increases, and when the pressure exceeds Pmax, the meniscus of the second nozzle 61 is broken and air is taken into the ink bag. As a result, the spring member 3 is restored, the negative pressure is relieved, and a meniscus is formed when it becomes Pmax or less. By repeating the above operation, most of the ink can be consumed.

[0045]

As described above in detail, according to the present invention, a flexible bag for accommodating ink in an ink cartridge is provided with a pair of rigid plates inside and a spring between them to make the entire flexible bag. Since the spring force acts evenly on the initial ink filling amount, a sufficient negative pressure can be secured and the negative pressure required for the inkjet recording device is generated and maintained. Highly reliable with characteristics,
It is possible to provide an inexpensive, small-sized ink cartridge having a simple structure, high ink use efficiency.

Further, in the present invention, since the air is introduced into the ink bag when the ink supply pressure reaches a predetermined negative pressure amount, normal recording can be performed and the ink use efficiency can be improved. It has become possible to raise it to almost 100%. As a result, it is possible to provide an ink jet recording apparatus that does not cause environmental pollution due to residual ink.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of an ink cartridge of the present invention.

FIG. 2 is a cross-sectional view showing the configuration of an ink bag in which the present invention is applied.

FIG. 3 is a perspective view showing the configuration of an ink bag embodying the present invention.

FIG. 4 is a sectional view showing an embodiment of the ink bag of the present invention.

FIG. 5 is a cross-sectional view showing another embodiment of the ink bag of the present invention.

FIG. 6 is a cross-sectional view showing another embodiment of the ink bag of the present invention.

FIG. 7 is a cross-sectional view showing another embodiment of the ink bag of the present invention.

FIG. 8 is a schematic view of a first embodiment of the inkjet recording apparatus of the present invention.

FIG. 9 is a detailed view of the first embodiment of the inkjet recording apparatus of the present invention.

FIG. 10 is a sectional view showing the operation of the first embodiment of the inkjet recording apparatus of the present invention.

FIG. 11 is a schematic view of a second embodiment of the inkjet recording apparatus of the present invention.

FIG. 12 is a schematic view showing a conventional inkjet recording apparatus.

FIG. 13 is a sectional view showing a conventional ink tank.

FIG. 14 is a sectional view showing an ink tank of another embodiment of the conventional example.

[Explanation of symbols]

 1 Flexible Ink Bag 2 Joint 3 Spring Member 4 Plate Member 5 Plug 6 Ink Cartridge Body 7 Ink Cartridge Lid 8 Plate Member 9 Adhesive Layer 10 Inkjet Recording Head 12 Pipe 15 Opening Member 16 Thin Plate 52 Sidewall 53 Upper and Lower Wall 54 Bellows 55 ink tank 56 elastic material 59 ink tank 60 ink bag 61 elastic body 62 ink outlet 210 flexible member 211 supply member 212 pipe 213 plate with projection 214 plate with hole 215 opening member 216 thin plate

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kenji Aono 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc.

Claims (7)

[Claims] 1. An ink cartridge used in an ink jet recording apparatus for guiding ink contained in an ink cartridge to a recording head, and ejecting the ink from a nozzle provided in the recording head toward a recording material. A flexible bag for accommodating ink, and a pair of rigid plate-like members inside the flexible bag and a spring member between the pair of plate-like members. ink cartridge. 2. The ink cartridge according to claim 1, wherein the spring member is a conical coil spring whose contact height is substantially equal to the wire diameter of the spring member. 3. The ink cartridge according to claim 1, wherein the pair of plate members and the spring member are integrally formed of the same material. 4. The ink cartridge according to claim 1, wherein any one surface of the flexible ink bag is fixed to an inner wall of the ink cartridge. 5. An inkjet recording head for recording on a recording material by ejecting ink using an energy converter, an ink cartridge having a sealed ink bag, the inkjet recording head and the ink cartridge. An ink jet recording apparatus comprising a connecting means for connection, wherein air enters the ink bag when the ink supply pressure reaches a predetermined negative pressure amount. 6. The ink jet recording apparatus according to claim 5, wherein air is introduced into the ink bag from at least a part of the flexible ink bag in the ink cartridge. 7. The ink jet recording apparatus according to claim 5, wherein air is introduced into the ink bag from at least a part of the recording head through the ink supply means.