JPH1034956A - Ink tank - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an ink tank for stably supplying ink to a recording means at the time of coupling while eliminating leakage of ink by an arrangement wherein an ink supply member is provided with a plurality of capillary tubes arranged in parallel with the direction for supplying ink from an ink containing part to an ink supply part and disposed through a space from a press contact body. SOLUTION: A space retaining member 108 is provided between a press contact body 106 and an ink supply member 107 along the inner wall face of an ink supply port and thereby a space 109 is produced between the press contact body 106 and the ink supply member 107 when they are not coupled. Since the ink supply member 107 directly touching the ink in an ink containing part is spaced apart from the press contact body 106 directly touching the outer air, ink is not leaked from the ink containing part even if a user touches the ink supply port inadvertently. When the press contact body 106 and the ink supply member 107 are coupled, the ink is passed through the ink supply member 107 and the part of the press contact body 106 abutting against the ink supply member and supplied surely to an ink supply tube.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink tank used in an ink jet recording apparatus for performing recording by discharging ink.

[0002]

2. Description of the Related Art At present, in a method of supplying ink for an ink jet recording apparatus or the like, a recording means and an ink tank having an ink container are separate bodies, and both can be separated from the recording apparatus. The configuration used is mainstream. In this method, the path from the ink storage section to the recording means is short, so that the size of the printing apparatus can be easily reduced. In addition, since ink can be supplied only by replacing the ink storage section, the running cost is reduced. It has the advantage of being good.

In such an ink supply method in which the ink tank section and the recording means are separable, a coupling section between the recording means and the ink tank (hereinafter, simply referred to as a coupling section).
When the recording means and the ink tank are integrated (hereinafter, referred to as
The ink tank is not leaked irrespective of the posture of the ink tank, and the ink is supplied stably regardless of the posture of the ink tank, and when the recording means and the ink tank are separated (hereinafter, when not combined). In addition, it is required to prevent ink leakage regardless of the attitude of the ink tank.

Here, many ink tanks having a structure in which a porous member such as a foam is provided in an ink storage section are intended to solve the above-mentioned problems by disposing a porous member in an ink supply section. . Further, as for an ink tank configured to directly store ink without having a porous member in the ink storage section, the ink supply section is made of an elastic member such as rubber as disclosed in JP-A-5-84924. There are known a configuration in which the ink supply tube is sealed and the shape of the ink introduction tube on the recording means side is a hollow needle shape, and a configuration in which a valve is used in an ink supply unit as disclosed in JP-A-63-13749. Further, as disclosed in Japanese Patent Application Laid-Open No. Hei 5-77438, there is also known an ink container in which a coupling portion is formed of an ink absorber made of a porous member, similarly to the case where a porous member is used for an ink storage portion. ing.

[0005]

However, in the above-mentioned prior art, there are technical problems to be solved.

That is, when the connecting portion is formed by an ink absorber made of a porous member, the opening of the connecting portion is generally directly exposed to the outside air. There is a problem that it is difficult. This problem can be solved, for example, by attaching a sealing member made of a resin film or the like to the opening portion of the connection portion when the connection is not performed. However, if the user forgets to attach the seal member, evaporation of the ink is inevitable.

In the case where the ink supply section is sealed by an elastic member such as rubber and the shape of the ink introduction tube on the recording means side is made into a hollow needle shape, if the hollow needle is inserted and removed for a long period of time, the elasticity of the ink supply section becomes high. A hole is formed in the member, and there is a possibility that ink leaks from the part at the time of connection and non-connection. Further, in order to ensure the safety of the user during the operation of connection and non-connection, it is necessary to provide a member that covers the periphery of the needle and to change the shape of the other accordingly. For this reason,
There has been a problem that the shape of the connecting portion of both the ink tank and the recording means is complicated and expensive.

In the case of a configuration using a valve in the ink supply unit, the number of parts constituting the valve is large and the mechanism is complicated. is there. Furthermore, since each member is generally made of a different material, not only does it violate the idea of cost reduction, but also the material must be selected while considering the incorporation and ink resistance of each member. There was also a problem that it did not.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned technical problem, and in the case where the connection and the non-connection are repeated, there is no ink leakage regardless of the posture of the ink tank in any state. Another object of the present invention is to provide an ink tank having a highly reliable connecting portion that can stably supply ink to a recording unit and suppress evaporation of ink when the ink is not connected.

[0010]

The specific objects of the present invention can be understood from the following constitution.

An ink tank according to the present invention has an ink storage section for storing ink, and an ink supply section for supplying the ink to a discharge head, wherein the ink supply section supplies ink to the discharge head. A pressure contact body that can be directly connected to the tube, and an ink supply member that can directly contact the ink in the ink storage unit, wherein the ink supply member has an ink supply direction from the ink storage unit to the ink supply unit. By providing an ink tank including a plurality of capillaries arranged in parallel and being separated from the press-contact body by a space, an ink tank having the above-described highly reliable coupling portion is provided. is there.

Further, the ink tank is substantially the same as or similar to the outer wall having a substantially polygonal column shape having an air communication portion and having a corner formed by three extended portions of the polygonal column. An inner wall that has an outer surface of a shape and a corner corresponding to the corner of the outer wall, forms an ink container therein, and is detachable from the outer wall, and a part where the inner wall is integrated with the outer wall. A pinch-off portion that is pinched, wherein the thickness of the inner wall is thinner at a portion forming a corner portion than at a central region of each surface of the substantially polygonal columnar shape, and the pinch-off portion is present on an opposite surface. The inner wall and the outer wall each have a surface having a maximum area on a surface excluding a surface on which the ink supply unit is provided and a surface having a pinch-off unit. , More stable ink supply and ink storage effect It is possible to provide an ink tank having an excellent.

[0013]

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

FIG. 1 is an explanatory diagram for explaining the joining of the ink tank of the present invention to an ink jet recording head.
(A) is a schematic view of the ink tank of the present invention and a recording head connectable to the ink tank, (b) is a cross-sectional view of the ink supply port of the ink tank of the present invention when not joined to the recording head, FIG. 3C is a cross-sectional view of the ink supply port of the ink tank of the present invention when joined to a recording head.

In FIG. 1A, reference numeral 401 denotes a recording head unit as recording means, which has recording heads for black, yellow, cyan, and magenta integrated so that full-color printing can be performed. Assembled. These recording heads have a liquid flow path having an ejection port for ejecting ink, and a heating resistor element for ejecting ink from the ink ejection port.

Reference numeral 402 denotes an ink supply tube as an ink introduction unit for introducing ink into each recording head unit. At the end of the ink supply tube 402, a filter 403 for trapping bubbles and dust is provided. Is provided.

On the other hand, the ink tank 100 is a connection part to the above-mentioned ink supply pipe, and is provided with a substantially cylindrical ink supply port 103 for allowing ink to be drawn out from an ink storage part (not shown) to the recording head. ing. The recording head unit 401 and the ink tank 100 are collectively referred to as an ink jet cartridge.

As shown in FIG. 1B, the ink supply port is provided with a pressure contact body 106 made of an absorbent having an elastic force, and an ink supply member 10 which is in direct contact with the ink inside the ink container.
7.

The pressure contact body 106 may be any material as long as it is elastically deformable, holds ink, and has an infinite number of ink flow paths.
On the other hand, the ink supply member 107 can hold the ink in the ink storage unit by the meniscus, and can prevent the ink leakage and the inflow of the air into the ink storage unit due to an external pressure change or impact. Ink supply member 107
For example, a member having a plurality of minute penetration spaces in the ink flowing direction, a porous member, or the like can be used. In addition, as the material, a fiber bundle or the like can be used.
It is more desirable to use plastic, metal, or the like in order to eliminate dust generated from fibers or the like in the ink container.

A space securing member 1 is provided between the pressing member 106 and the ink supply member 107 along the inner wall surface of the ink supply port.
08 is provided, and the space securing member forms a space 109 between the press-contact body and the ink supply member at the time of non-connection, so that the space has air. The space securing member may be of any configuration as long as it forms the above-mentioned space 109 when it is not connected, and the ink supply member 107 and the pressure contact body 106 may be connected to the ink supply port by devising the attachment. When the space 109 is surely generated even in the case where the unbonding is repeatedly performed, it is not necessary to provide the space 109.

This space 109 is surrounded by the ink supply member 107 and the pressure contact body 106 at the ink supply port, and forms a substantially closed space. Therefore, the humidity of the space is higher than that in the atmosphere, and the ink supply member The evaporation of the ink in the ink tank can be suppressed as compared with the case where the ink tank is open to the outside air. Furthermore, since the ink supply member that is in direct contact with the ink inside the ink container is provided with a space separated from the pressure contact body that is directly in contact with the outside air, even if the user accidentally touches the ink supply port. No ink leakage from the ink storage portion occurs.

The rise in the external temperature causes the space 10
Although it is conceivable that the air of No. 9 expands, in this case, since the expanded air is opened to the outside via the pressure contact body 106, the air does not enter the inside of the ink container. In addition, the size of the space 109 is limited to a size that allows the ink supply member and the press-contact body to reliably come into contact with each other at the time of coupling described below.

Then, as shown in FIG. 1C, at the time of connection, the ink supply pipe 402 is pressed against the pressure contact body 106, and the pressure contact body is elastically deformed and comes into contact with the ink supply member 107.
At this time, the air existing in the space 109 is opened to the outside via the pressure contact body 106.

At the time of connection, the ink in the ink storage portion passes through the ink supply member 107, passes through the portion of the pressure contact body 106 in contact with the ink supply member, and is reliably supplied to the ink supply tube. Here, the capillary force of the ink supply pipe is
It is desirable that the pressure is smaller than the capillary force of the press-contact body because the ink can be supplied more smoothly.

Next, the configuration and operating principle of the negative pressure generating means of the ink tank of the present invention will be described in detail with reference to FIGS.

FIGS. 2A to 2C are schematic diagrams showing the structure of an ink tank according to an embodiment of the present invention.
(A) is a sectional view, (b) is a side view, and (c) is a perspective view. As can be seen from FIG. 2C, of the surfaces constituting the outer wall of the tank of FIG. 1, the surface having the maximum area is indirectly displayed as in the cross-sectional view of FIG. Face. FIG. 3 is a schematic diagram showing changes when ink is stored in the ink tank of FIG. 2 and ink is drawn out from the ink supply unit of the ink tank in the order of (a) to (d). 2B is a sectional view taken along the line BB, and the suffix 2 is a sectional view taken along the line AA in FIG. 2A. The ink tank of the present invention is manufactured by a method in which the inner wall and the outer wall of the ink tank are simultaneously formed in one step by direct blow molding described later.

In the ink tank 100 shown in FIG. 2, ink is stored in a region (hereinafter referred to as an ink storage portion) surrounded by an inner wall 102 which can be separated from an outer wall 101 forming an outer shell. The outer wall 101 is sufficiently thicker than the inner wall 102, and hardly deforms even if the inner wall 102 deforms due to the outflow of ink. The outer wall is an air intake 105
have. The inner wall has a welded portion (pinch-off portion) 104, and the inner wall is supported by the welded portion so as to engage with the outer wall.

Here, the ink tank of FIG. 2 will be described in detail. The ink tank 100 is composed of eight planes, and a cylindrical ink supply section 103 is added as a curved surface. Of these eight surfaces, the ink supply unit 10
3 has six corners (α1, β1, β1, β1, β1, β2,...) Described later.
1, α1), (α2, β2, β2, β2, β2, α2)
It is divided by.

The thickness of the inner wall surface which forms the maximum area is smaller at the corner portions than at the central region of each surface of the substantially polygonal column, and gradually increases from the central region of each surface toward each of the corners. And has a convex shape on the ink storage unit side. This direction is, in other words, the same as the surface deformation direction, and has the effect of promoting the deformation described later.

Here, since the corner of the inner wall is formed of three surfaces as described later, the strength of the entire corner of the inner wall is relatively higher than the strength of the central region. Further, when viewed from the extension of the surface, the thickness is smaller than that of the central region, so that the movement of the surface described later is permitted. It is desirable that the portions constituting the corners of the inner wall have substantially the same thickness.

The ink supply section 103 has a structure in which the inner wall and the outer wall are difficult to separate. Further, γ1 and γ2, which are the intersections between the curved surface and the plane of the cylinder described later, have an inner wall that accompanies the derivation of the ink by the discharge of the ink from the ordinary ink jet recording means because the ink supply unit is substantially cylindrical. It has the property of not being easily collapsed by deformation. In the ink tank of the present embodiment, the ink supply unit is substantially cylindrical, but is not limited to a substantially cylindrical shape. Even in the case of the polygonal column shape, the size of the ink supply unit is sufficiently smaller than that of the ink storage unit. Therefore, even when the consumption of the ink is completely completed, the inner wall and the outer wall of the ink supply unit maintain the initial state without being deformed.

Since FIGS. 2 and 3 are schematic diagrams, the outer wall 101 of the ink tank and the inner wall 10 of the ink tank are not shown.
The positional relationship with 2 is drawn as if it were separated by space,
Actually, it is sufficient that the inner wall and the outer wall are in a separable state. The inner wall and the outer wall may be in contact with each other or may be configured to be arranged with a small space therebetween. Therefore, in any case, in the initial state of use (initial state), the ink tank is positioned at least at a position corresponding to the corners α1 and β1 of the outer wall 101 along the shape of the inner surface of the outer wall 101.
No. 02 is formed so that the corners α2 and β2 come (FIGS. 3A1 and 3A2).

Here, the corner portion refers to a portion corresponding to an intersecting portion where at least three surfaces, more preferably three planes intersect, or an intersecting portion of an extended surface thereof, in an ink tank constituted by a substantially polyhedron. It is a meaning that includes. The meanings of the signs of the corners indicate that α is a corner formed by the surface having the ink supply port, β is the other corner, and that subscript 1 is an outer wall and subscript 2 is an inner wall. ing. Further, the ink supply portion is formed in a substantially cylindrical shape. Here, when the intersection between the curved surface of the cylinder and the substantial plane is represented by γ, the outer wall and the inner wall are also at corresponding positions at this intersection. And they are respectively referred to as γ1 and γ2 below. The corners may be provided with minute curved surfaces. At this time, the surface is defined as a plane excluding the minute curved surface portion, taking the minute curved surface portion of the polyhedron as a corner.

After the ink is discharged from the ink jet recording head of the ink jet recording means and the ink in the ink container starts to be consumed, the inner wall 102 is positioned at the center of the surface having the largest area in the direction in which the volume of the ink container is reduced. Deformation starts from the part. Here, the outer wall functions to suppress the displacement of the corner of the inner wall. This ink tank has the above-mentioned corner α
2. Since there is almost no positional change in the corners divided by β2, the ink storage unit is acted on by the force of deformation due to ink consumption and the force of returning to the initial state, thereby stabilizing the negative pressure. To work.

At this time, air is introduced into the space between the inner wall 102 and the outer wall 101 from the air intake port 105, and serves to maintain a stable negative pressure during ink use without hindering deformation of the inner wall. . That is, the space between the inner wall and the outer wall communicates with the outside air through the air intake 105. Thereafter, the ink on the inner wall and the force of the meniscus at the ejection port of the recording head are balanced, so that the ink is held in the ink storage section (FIGS. 3B1 and 3B2).

Further, when a considerable amount of the ink in the ink container is led out (FIGS. 3 (c1) and 3 (c2)), the ink container is deformed in the same manner as described above, and the center of the ink container is moved inward. A stable crushing way toward is maintained. Further, the welded portion 104 also serves as a deformation regulating portion of the inner wall, and the portion having no pinch-off portion starts to deform first on the surface adjacent to the surface having the maximum area, compared with the region having the pinch-off portion 104. Separated from outer wall.

However, with only the above-mentioned inner wall deformation restricting portion, the inner wall near the ink supply unit is deformed, thereby blocking the ink supply unit, and may not be able to use the ink stored in the ink storage unit sufficiently. There is.

In the present invention, the corner α2 of the inner wall shown in FIG. 2C is formed along the corner α1 of the outer wall in the initial state, so that when the inner wall is deformed, other portions of the inner wall may be formed. The corner portion α2 of the inner wall is less likely to be deformed than in the case of, and the deformation of the inner wall can be restricted. The inner wall of this ink tank is
The angle formed by the plurality of corners α2 is expressed as 90 degrees.

Here, the angle of the corner portion α2 of the inner wall is defined as the angle formed by two of at least three of the substantially planar surfaces forming the corner portion α1 of the outer wall, that is, the intersection of the two extended surfaces. Defined as the angle of the part. The angle of the corner of the inner wall is defined by the angle of the corner of the outer wall in order to manufacture the outer wall as a reference in a manufacturing process described later, and as described above, the inner wall and the outer wall are substantially similar in the initial state. This is because

As described above, in FIGS. 3 (c1) and (c2), the corner α2 of the inner wall shown in FIG. 2 (c) is positioned so as to be separable from the corresponding corner α1 of the outer wall. on the other hand,
The corner β2 of the inner wall other than the corner formed by the surface having the ink supply port is slightly away from the corresponding corner β1 of the outer wall as compared with α2. However, in the embodiments shown in FIG. 1 and FIG. 2, in many cases, β at the opposing position is formed by an angle of 90 degrees or less. Therefore, the positional relationship with the corresponding outer wall can be maintained at a position closer to the initial state as compared with the region of the other inner wall forming the ink containing portion, and thus the auxiliary support of the inner wall is realized.

Furthermore, in FIGS. 3 (c1) and 3 (c2), the opposite surfaces having the largest surface area, which will be described later, deform almost simultaneously, so that the center portions of the ink storage portions come into contact with each other. The contact portion at this center (FIG. 3 (c1), (d)
The hatched portion (1)) is further expanded by further deriving the ink. That is, the ink tank of the present invention
Before deriving the ink, before the edge formed by the surface having the maximum area and the surface adjacent to the surface having the maximum area is bent, the surface having the maximum area comes into contact with the opposing surface.

Eventually, almost all of the ink stored in the ink storage section is used (hereinafter, referred to as a final state).
However, the state at this time is shown in FIGS. 3 (d1) and (d2).

In this state, the contact portion of the ink containing portion covers almost the entire area of the ink containing portion and the corner portion β of the inner wall.
In some cases, some of them are completely separated from the corresponding corners β1 of the outer wall. On the other hand, the corner α2 of the inner wall is
Even in the final state, it is positioned so as to be separable at the corresponding corner portion α1 of the outer wall, and serves as a deformation regulating portion of the inner wall to the end.

Further, in this state, the welded portion 104 may separate from the outer wall depending on the thickness of the inner wall. In this case, since the welded portion 104 has a length component, the deformation direction is Limited. Therefore, even when the welded portion comes off the outer wall, the deformation is not irregular, and the deformation is performed while maintaining the balance.

The change when the ink is stored in the ink storage section of the ink tank of the present invention and the ink is drawn out from the ink supply section is as described above. Before the edge formed by the adjacent surface is bent, the surface having the largest area comes into contact with the opposite surface, and the corners other than the corner formed by the surface having the ink supply unit move, thereby causing deformation of the ink tank. In this case, the configuration has a priority of the deformation.

Here, at least one of the surfaces having the largest area among the substantially planar surfaces of the outer wall of the ink tank constituted by the substantially polygonal prism, which is one of the stable negative pressure generating mechanisms, is provided. The fact that it is not fixed to the inner wall will be described in more detail.

In the above configuration, when the ink in the ink storage portion is reduced by the discharge of the ink from the ink jet recording head, the inner wall of the ink tank is most likely to be deformed under the condition of the above-described structure for restricting the deformation. Attempt to begin deformation. Here, in the present embodiment, at least one of the surfaces having the largest surface area among the substantially planar surfaces of the ink tank outer wall formed by the polyhedron is not fixed to the inner wall,
Deformation starts from the substantially central portion of the inner wall surface corresponding to this surface.

Since this surface has a substantially planar shape, the surface is uniformly and continuously deformed in the direction in contact with the opposing surface in accordance with the amount of ink reduction in the ink container. Therefore,
There is no discontinuous large deformation of the ink storage section during ejection and non-ejection, making it possible to maintain a more stable negative pressure and stabilize the negative pressure at the time of ink ejection, which is optimal for an ink tank used in an ink jet recording apparatus. It is possible to realize.

Further, as in this embodiment, the pair of opposing surfaces both have the largest surface area, do not have a joint between the inner wall and the outer wall, and can be easily peeled off. Since the deformation is performed, it is possible to further maintain the negative pressure and stabilize the negative pressure between the ink and the source.

The volume of the ink-jet ink tank to which the present invention is applied, up to 500 cm ^3, a commonly range used is about 5 to 100 cm ^3.

The maximum surface area of the ink tank,
In the case of an ink tank having the above capacity, a desirable range of the size ratio with respect to the other surface can be determined as follows. That is, as shown in FIG. 4, a rectangular parallelepiped having a minimum size capable of containing the ink tank of the present invention inside is considered, and the sides of the rectangular parallelepiped are set to l1, l2, l3 (l
If 1 ≧ l2> l3), the ratio of the lengths of l1 and l3 is
About 10: 1 to about 2: 1 is desirable. The ratio of this length is, especially when the ink tank is a substantially rectangular parallelepiped,
The area relative to the total surface area can be determined. In the ink tank of the present invention, the surface having the largest area is larger than the total area of the surfaces adjacent to the surface.

According to the present inventors, the thickness at the center of the inner wall surface is about 100 μm, and the thickness near the corner is several μm to 10 μm.
The experiment was performed with an ink tank of about m. In this case, since the corners are the intersections of the three surfaces, the substantial thickness is about three times, that is, has a strength equivalent to a thickness of about 10 × 3 of about 30 μm.

Attention was paid to the negative pressure of the container and the method of crushing under such conditions. First, in the initial state where the discharge of the liquid started, the above-mentioned corners and the intersections between the surfaces were changed. A predetermined negative pressure could be generated by regulating the flattening of the surface.

Further, as the derivation of the liquid proceeds, the deformation proceeds from the vicinity of the center of the maximum area surface of the container. As the liquid is further led out, the inner wall corners of the surface begin to separate from the corresponding outer wall corners. Immediately after the corner is detached, the original shape of the corner is maintained and the surface is crushed by maintaining the original shape.However, in the case of this configuration, since the inner wall is as thin as 100 μm, the liquid As the derivation of proceeds, the shape of the corner cannot be maintained and gradually deforms.

However, at this time, not all the corners composing the liquid container are separated and deformed at the same time, and the corners are individually separated and deformed in a priority order.

This order is determined by the shape of the liquid container, the film thickness of each corner, and the like, and the position of the pinch-off portion where the inner walls are welded to each other and the inner wall is sandwiched by the outer walls. By providing this pinch-off portion at a position as in this embodiment, deformation of the inner wall at that position,
In addition, since detachment from the outer wall can be regulated, irregular deformation of the inner wall can be prevented. Further, by providing a pinch-off portion at a position facing the same as in the present invention, a more stable negative pressure can be generated.

As described above, since the corners constituting the liquid container are sequentially removed, a predetermined negative pressure can be stably generated from the initial stage of liquid derivation to the full use of the liquid. It has become possible. It should be noted that the 100 μm
When the inner wall has a sufficient thickness, the corners and the intersections between the surfaces are irregularly deformed in the direction depending on the ink supply unit in the used-up state.

Next, the thickness at the center of the inner wall surface is 100 to 40.
A similar experiment was performed on a liquid container formed under the conditions of 0 μm and a thickness in the range of 20 to 200 μm near the corner. In this case, the strength of the corner is considerably higher than that described above.

When an experiment was conducted under these film thickness conditions, a predetermined negative pressure could be generated in the initial stage of liquid derivation, as in the case of the container having the above-mentioned film thickness. Further, when the liquid is further led out, peeling and deformation from the outer wall are performed gradually from near the center of the surface. Corresponding to this deformation, the corners also begin to detach from the corresponding corners of the outer wall. Under the conditions of the present film thickness, even if the derivation of the liquid is considerably advanced, the deformation of the corner is suppressed minutely because the force for restricting the collapse of the corner is strong. Further, since the corners are separated while the initial shape is maintained to some extent, a more stable negative pressure can be generated. Even in the use-up state, the shape is stabilized by the corners, so that the remaining liquid inside can be kept to a minimum and a negative pressure can be stably generated to the end.

As a result of further experiments, it was found that the more preferable thickness condition is that the thickness near the center of the inner wall surface is 100%.
It was found that those having a thickness of about 250 μm and a thickness near the corners of 20 to 80 μm can generate a particularly stable negative pressure.

Next, a method of manufacturing the above-described ink tank will be briefly described.

Here, the ink tank provided by the present invention employs a double-walled structure made of a molding resin material to make the outer wall thicker to have strength, while using a softer material for the inner wall. By making it thinner, it can follow the volume fluctuation of the liquid stored inside. As a material used for each wall, it is preferable that the inner wall has liquid resistance and the outer wall has impact resistance and the like.

In the present embodiment, blow molding using blowing air was employed as a method of manufacturing an ink tank. This is because the wall forming the ink tank is formed of a resin that is not substantially stretched, and thereby the inner wall of the ink tank forming the liquid container can withstand a substantially uniform load in any direction. Like that. Therefore, even when the liquid contained in the ink tank inner wall swings in any direction while the liquid is consumed to a certain extent, the ink tank inner wall can reliably hold the liquid, and the overall ink tank durability can be improved. Have improved.

As the blow molding method, there are a method using injection blow, a method using direct blow, a method using double wall blow, and the like. A method using direct blow will be briefly described.

First, a multi-layer nozzle is used as the injection nozzle, and the first and second parisons are integrated by simultaneously injecting the inner resin and the outer resin into the mold.
In this case, the surface where the inner resin and the outer resin are in contact with each other should be made of a material that does not cause the resin to weld to each other. Or the outer material may be multi-layered and the resin may be supplied so that different materials are located on the contact surface.

Next, with respect to the integrated parison, a mold arranged so as to sandwich the parison moves to sandwich the parison, air is injected from an air nozzle, and blown into a shape suitable for the mold. You. At this time, the inner wall and the outer wall are in close contact with no gap. Further, since the parison is processed in a viscous state, neither the inner wall resin nor the outer wall resin has orientation. As described above, by using blow molding as a method of manufacturing an ink tank, not only the number of steps during manufacturing and the improvement in yield due to a reduction in the number of parts, etc., but also the ink tank as shown in FIG. According to the shape of the outer wall 101, the outer wall 1
The shape of the inner wall 102 can be made such that the corner of the inner wall 102 comes to a position corresponding to the corner of No. 01.

Next, the inner and outer walls other than the liquid supply section are peeled off. As a method of separating the inner wall and the outer wall other than performing the evacuation, there is a method of using materials having different thermal expansion rates (shrinkage rates) for the molding resin forming the inner wall and the outer wall. In this case, after the blow molding, the temperature of the molded product decreases, so that the molded product can be automatically peeled, and the number of steps can be reduced. Similarly, during blow molding, an external force is applied to the part sandwiching the parison between the molds after molding to separate the inner wall and the outer wall, and the gap is communicated with air, which can be used as an atmosphere communication port. Is more preferable because the number of steps can be reduced.

As described above, after the portion excluding the ink supply port is integrally formed, the ink is injected. After the ink is injected, the ink tank is completed by attaching the ink supply member 107, the space securing member 108, and the pressure contact body 106.

As the material used for the ink tank of the present invention, polyethylene resin, polypropylene resin and the like can be applied as described above, but the tensile elastic modulus used as the inner wall is about 150 to 3000 (kgf / cm 2). Preferably, the condition is satisfied. Within this numerical value, a material within a desired range can be selected depending on conditions such as the shape and thickness of the container and the desired negative pressure performance.

In the above description, the negative pressure generating means of the ink tank has been described as a bag-shaped configuration which deforms as ink is drawn out. Without being limited, a known material such as a structure using a conventional porous member can be used.

[0071]

By using the ink tank of the present invention,
In the case of repeating the combination and the non-combination, the ink is not leaked regardless of the posture of the ink tank in any state, and the ink is stably supplied to the recording means at the time of the combination, and the ink is It is possible to provide an ink tank having a highly reliable connecting portion capable of suppressing evaporation of the ink.

In particular, as the negative pressure generating mechanism for the ink tank, an outer wall having a substantially polygonal column shape having a substantial air communication portion and having a corner formed by three extended portions of the polygonal column; An inner wall which has an outer surface of the same or similar shape to the outer wall and a corner corresponding to the corner of the outer wall, forms an ink container therein, and is detachable from the outer wall, and a portion where the inner wall is integrated Has a pinch-off portion that is pinched to the outer wall, and the thickness of the inner wall is smaller at a portion forming a corner portion than at a central region of each surface of the substantially polygonal columnar shape, and the pinch-off portion faces each other. Existing on a surface, the inner wall and the outer wall have a configuration having a surface having a maximum area on a surface excluding a surface on which the ink supply unit is provided and a surface having a pinch-off unit. Less ink tank with excellent storage efficiency and use efficiency Easily it can be provided in number.

[Brief description of the drawings]

FIGS. 1A and 1B are explanatory views illustrating the joining of an ink tank of the present invention to an ink jet recording head. FIG. 1A is a schematic diagram of an ink tank of the present invention and a recording head connectable to the ink tank. ) Is a cross-sectional view when the ink supply port of the ink tank of the present invention is not joined to the recording head,
FIG. 3C is a cross-sectional view of the ink supply port of the ink tank of the present invention when joined to a recording head.

FIG. 2 is a schematic view of the ink tank of the present invention;
(A) is a sectional view, (b) is a side view, and (c) is a perspective view.

FIG. 3 shows (a1) to (d1) and (a2) to (d2)
It is the schematic diagram which shows the deformation | transformation accompanying ink derivation of the ink tank of this invention.

FIG. 4 is a schematic explanatory view for defining the size of the ink tank of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 100 ink tank 101 outer wall 102 inner wall 103 ink supply port 104 pinch-off section 105 atmosphere communication section 106 press-contact body 107 ink supply member 108 space securing member 109 space

Claims (5)

[Claims] An ink storage unit for storing ink; an ink supply unit for supplying the ink to an ejection head;
In the ink tank, the ink supply unit includes: a press-contact body directly connectable to an ink introduction pipe of the ejection head; and an ink supply member capable of directly contacting ink in the ink storage unit. An ink tank, wherein the ink supply member includes a plurality of capillaries arranged in parallel with a direction in which ink is supplied from the ink storage section to the ink supply section, and is provided with a space separated from the press-contact body. 2. The ink tank according to claim 1, wherein the pressure contact body is elastically deformed when connected to the ink introduction pipe of the ejection head, and presses against the ink supply member. 3. The ink tank according to claim 1, further comprising a space holding member between the pressure contact member and the ink supply member. 4. The apparatus according to claim 1, wherein a capillary force of said ink supply member is smaller than a capillary force of said press-contact body.
The ink tank according to any one of the above. 5. The ink tank has a substantially polygonal column shape having a substantial air communication portion, and an outer wall having a corner formed by three extended portions of the polygonal column; An outer surface having a similar shape, a corner corresponding to a corner of the outer wall, an inner wall that forms an ink container therein and that can be peeled off from the outer wall, and a portion where the inner wall is integrated A pinch-off portion sandwiched by the outer wall, wherein the thickness of the inner wall is smaller at a portion forming a corner portion than at a central region of each surface of the substantially polygonal columnar shape, and the pinch-off portion is a surface facing the Wherein the inner wall and the outer wall have a surface having a maximum area except for a surface on which the ink supply unit is provided and a surface having a pinch-off unit. The ink tank according to any one of the above.