JP3021449B1 - Ink supply device for inkjet printer - Google Patents

Abstract

Abstract: PROBLEM TO BE SOLVED: To make the flow of ink flowing from a porous body in an ink cylinder into a printing apparatus smooth, and to prevent bubbles existing in the porous body from flowing into the printing apparatus. SOLUTION: An ink cylinder containing ink and a layer having a different pore number density are laminated so as to have a higher pore number density as approaching an ink supply portion, and a porous hole is provided inside the ink cylinder to contain ink. A thin layer of a porous body having a lower pore number density than the porous body directly in contact with the porous body, which is inserted into the lower end of the porous body inside the ink cylinder; An ink supply unit that supplies the ink contained in the substrate to the recording apparatus, and a filter arranged at a connection portion between the ink cylinder and the ink supply unit,
A recording device that records by supplying the supplied ink through a nozzle, and an exhaust that is formed at the top of the ink cylinder and contacts the ink inside the ink cylinder with air to form a negative pressure inside the ink With mouth.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink supply apparatus for an ink-jet printer, and more particularly, to a method of mounting a porous body inside an ink cylinder containing ink and forming an exhaust port at the top of the ink cylinder. Further, the present invention relates to an ink supply device of an ink jet printer that supplies ink in an ink cylinder to a recording device by utilizing a capillary phenomenon caused by a negative pressure generated inside the ink.

[0002]

2. Description of the Related Art An ink supply device of an ink jet printer generally includes an ink cylinder containing ink, a porous body mounted inside the ink cylinder to contain ink, and
An ink supply unit connected to a lower part of the ink cylinder to supply ink contained in the porous body to a recording apparatus; a filter arranged at a connection portion between the ink cylinder and the ink supply unit; A recording device connected to a supply unit for recording by ejecting ink supplied from the ink supply unit through a nozzle, and an ink formed in an upper portion of the ink cylinder to contact ink inside the ink cylinder with air And an exhaust port for forming a negative pressure inside the ink. Then, when the recording apparatus operates, the ink contained in the ink cylinder flows into the recording apparatus via the ink supply unit.

[0003] The ink supply device of the ink-jet printer thus configured forms negative pressure inside the ink, thereby containing the ink in the ink cylinder and stabilizing the ejection surface of the recording device.

In order to generate a negative pressure inside the ink at the ink supply portion, most of the conventional ink supply devices mount a porous body inside the ink cylinder, and cause a capillary phenomenon formed in the porous body to occur. I have used it.

[0005] Two typical forms of an ink supply apparatus for supplying ink to a recording apparatus utilizing the capillary phenomenon are as follows.

[0006] A first conventional ink supply device includes an ink cylinder containing ink and layers having different pore number densities stacked so as to increase the pore number density as approaching the ink supply unit, and are provided inside the ink cylinder. Attached porous body,
An ink supply unit connected to a lower part of the ink cylinder to supply ink contained in the porous body to a recording apparatus; a filter arranged at a connection portion between the ink cylinder and the ink supply unit; A recording device connected to a supply unit for recording by ejecting ink supplied from the ink supply unit through a nozzle, and an ink formed in an upper portion of the ink cylinder to contact ink inside the ink cylinder with air And an exhaust port for forming a negative pressure inside the ink.

[0007] In the ink supply device having such a configuration, in order to promote the inflow of the ink inside the ink cylinder from the ink supply portion, which is a passage for supplying the ink from the ink cylinder to the recording device, the ink supply device has a pore number density. Have laminated porous bodies of different layers from each other. In stacking, the porous body located near the ink supply unit is arranged such that the pore density of the porous body is higher than that of the porous body in other parts. The ink supply device of such a form is shown in FIG.
As shown in FIG.

As shown in FIG. 1, in this ink supply apparatus, a porous body 102, 103, 1 is provided inside an ink cylinder 101.
04 are laminated, and the pore number density of the porous body is 10
2. The porous body 103 increases in the order of the porous body 103 and the porous body 104, and the porous body 104 located near the ink supply unit has the highest pore number density and the porous body 1 located farthest from the ink supply unit.
02 is arranged so as to have the lowest pore number density.

The ink contained in the ink cylinder interior 101 comes into contact with air at atmospheric pressure via an exhaust port 107, and at the boundary where the ink and air come into contact, the ink is large inside the ink due to the surface tension of the ink. A negative pressure below atmospheric pressure is generated.

When the amount of ink contained in the ink cylinder 101 is reduced, the porous body having a high pore number density, which has been immersed in the ink, is exposed and comes into contact with air. Then, the negative pressure generated inside the ink by the surface tension is
It becomes even larger. Therefore, the ink in the other portion where the internal negative pressure is relatively low is supplied to the ink supply unit 10 where the internal negative pressure is high.
Move to the 5th side.

When the ink moves toward the ink supply unit 105, impurities and bubbles contained in the ink are separated by a very fine filter 108 disposed between the ink cylinder 101 and the ink supply unit 105. At this time,
Since the filter 108 separates not only the impurities contained in the ink but also the bubbles contained in the ink, it is necessary to use a filter having very small pores.

A second conventional ink supply device comprises a porous member mounted inside an ink cylinder and ribs arranged on the ink supply portion side to increase the pore density of the porous member on the ink supply portion side. The member, a structure disposed between the ink supply unit and the porous body in order to increase the pore number density on the ink supply unit side of the porous body, and a porous body that is connected to a lower part of an ink cylinder and is connected to the porous body. An ink supply unit that supplies the contained ink to the recording apparatus, a filter disposed at a connection portion between the ink cylinder and the ink supply unit, and a filter connected to the ink supply unit and supplied from the ink supply unit. A recording device for recording by ejecting ink through nozzles, and an exhaust port formed at the top of the ink cylinder to contact the ink inside the ink cylinder with air to form a negative pressure inside the ink. Have

In the ink supply device having such a configuration, a porous body having a constant pore number density is mounted inside the ink cylinder instead of having several porous bodies having different densities. However, the structure disposed between the ink supply unit and the porous body and the rib members disposed on the upper surface inside the ink cylinder press the porous body around the ink supply unit, thereby causing the structure around the ink supply unit to be reduced. In order to increase the pore number density of the located porous body portion, the same effect as when the porous bodies having different pore number densities are stacked is exhibited. The ink supply device of such a form is as shown in FIG.

As shown in FIG. 2, this ink supply apparatus is a method of forming a porous body having a constant pore number density into an ink cylinder 11.
1 inside. A structure 113 is provided between the ink supply unit 115 and the porous body 112 to improve the flow of ink as the ink supply unit 115, and a rib member 1 is provided on the upper surface inside the ink cylinder 111.
14 are arranged.

The structure 113 disposed between the ink supply unit 115 and the porous body 112 and the rib member 114 disposed on the upper surface of the ink cylinder 111 form the porous body 112 around the ink supply unit 115. Hold down. Therefore, the pore number density of the porous body 112 around the ink supply unit 115 is increased.

As in the case of the ink supply apparatus shown in FIG. 1, the ink immersed in the porous body 112 comes into contact with air at atmospheric pressure through the exhaust port 117, and the ink and air come into contact with each other. At the boundary surface, a negative pressure lower than the atmospheric pressure is generated inside the ink due to the surface tension of the ink.

When the amount of ink inside the ink cylinder decreases, the porous body portion having a high pore number density, which has been immersed in the ink in the porous body 112, is exposed and comes into contact with air. The negative pressure generated inside the ink by the tension is further increased. As a result, the other portion of the ink having a relatively low internal negative pressure moves toward the ink supply unit, causing a capillary phenomenon.

At this time, too, a very fine filter 118 is provided between the ink cylinder 111 and the ink supply section 115.
Are arranged to separate impurities and bubbles contained in the ink.

The ink supply device shown in FIG. 1 and the ink supply device shown in FIG. 2 can be mixed.

[0020]

However, the above-described ink supply apparatus has the following problems.
In addition, when a porous body having a high pore number density is used in the ink supply device, there is an advantage that the negative pressure generated inside the ink can be increased, but since the porous body has a high porous number density, Ink flow may be reduced.

Secondly, air in the atmosphere flows into the ink cylinder through the exhaust port. As a result, the bubbles may flow into the porous body and may be present. Without being eliminated, it may flow into the recording apparatus via the ink supply unit.

In particular, when the pore number density of the porous body is increased, small bubbles entering the porous body are liable to adhere to the surface of the porous body. It moves along with it and tends to flow into the recording device. In such a situation, an error occurs in the operation of the recording apparatus, and in some cases, the recording apparatus may be damaged.

Third, the problem of air bubbles flowing into the recording device can be prevented to some extent by placing a very fine filter on the path to the recording device.
However, it is impossible to completely prevent air permeating into the recording apparatus only by disposing such a filter. Also, since the pores of the filter are very small, the fluid resistance increases. Therefore, there is a problem that a smooth ink flow is impaired, and in order to solve the problem, the pressure of the ink flowing into the recording apparatus must be increased.

Fourth, if the ink is discharged quickly during the maintenance of the printing apparatus, air may enter the ink supply unit and flow into the printing apparatus.

The flow rate of the ink due to the natural capillary phenomenon is lower than the flow rate of the ink discharged in the process of maintaining the recording apparatus. Therefore, during the maintenance process, after the ink around the ink supply unit is discharged at a high flow rate, the air cuts off the flow of ink before the ink at a portion far from the ink supply unit moving at a low flow rate arrives at the ink supply unit, Enter the ink supply unit. In particular, this phenomenon is likely to occur when the amount of ink inside the ink cylinder is small.

Even if such a phenomenon occurs, if the amount of ink in the ink cylinder is more than a certain amount, the problem is solved to some extent by repeating the maintenance process after waiting until the ink refills around the ink supply section. I do. However, if the amount of ink inside the ink cylinder is small and the area around the ink supply unit cannot be filled with ink, the ink supply device cannot be reused.

Fifth, in order to prevent air from flowing into the recording apparatus, the structure inside the ink cylinder is deformed into various forms. However, the overall structure of the ink supply apparatus becomes complicated, and the ink supply apparatus becomes complicated. There is also a problem that it is costly to change the structure inside the cylinder.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to make it possible to smooth the flow of ink flowing from a porous body inside an ink cylinder into a recording apparatus while maintaining a smooth flow of ink. An object of the present invention is to provide an ink supply device capable of preventing bubbles existing inside the body from flowing into a recording device.

[0029]

In order to achieve the above object, the present invention provides an ink container containing ink and a layer having different pore number densities stacked so as to increase the pore number density as approaching the ink supply section. The porous body attached to the inside of the ink cylinder to contain ink, the pore number density is higher than the pore number density of the porous body that is inserted at the lower end of the porous body inside the ink cylinder and directly contacts. A thin layer of a low porous body, an ink supply unit connected to a lower portion of the ink cylinder and supplying an ink contained in the porous body to a recording apparatus,
A filter disposed at a connection portion between the ink cylinder and the ink supply unit, a recording device that records by supplying the supplied ink through a nozzle, and an ink cylinder formed on the upper part of the ink cylinder An exhaust port that forms a negative pressure inside the ink by bringing the ink inside into contact with air is provided.The flow of ink flowing from the ink cylinder to the recording device through the ink supply port is smooth, and air bubbles are recorded. The gist of the invention is to prevent inflow into the device.

According to the present invention, there is provided an ink container containing an ink, a porous body mounted inside the ink container so as to contain the ink, and a recording medium connected to the ink container and ejecting the ink. A recording device, an ink supply unit connected to a lower portion of the ink cylinder to supply the ink contained in the porous body to the recording device, and a pore number density on the ink supply unit side of the porous body. A rib member disposed on the upper surface inside the ink cylinder to increase the number density of pores on the ink supply section side of the porous body; and a porous member disposed inside the ink cylinder. A thin layer of a porous body inserted between the lower end of the porous body on the ink supply unit side and the structural body and having a pore number density lower than the pore number density of the porous body; the ink cylinder and the ink supply unit Placed at the connection site with A filter, and an exhaust port formed at the top of the ink cylinder to form a negative pressure inside the ink by bringing the ink inside the ink cylinder into contact with air, and from the ink cylinder through an ink supply port. The gist of the present invention is to make the flow of the ink flowing into the printing apparatus smooth and prevent bubbles from flowing into the printing apparatus.

[0031]

DESCRIPTION OF THE PREFERRED EMBODIMENTS First, the present invention comprises an ink cylinder, a plurality of layers of a porous body, a thin layer of a porous body, an ink supply section, a filter, a recording device, and an exhaust port. ing.

The porous body mounted inside the ink cylinder is formed by laminating a plurality of types of porous bodies having different pore number densities. The pore number density of such a porous body increases from the top to the bottom, the pore number density of the lowest porous body is the highest, and the pore number density of the highest porous body is the lowest. Has become.

The porous body mounted inside the ink cylinder is 8
It is preferable to use one having a pore number density of 0 to 200 ppi (pore per inch). This is because when the pore number density of the porous body exceeds 200 ppi, it becomes difficult to discharge the ink simply because it contains ink, and the pore number density becomes 80 ppi.
If less than, the porous body does not contain much ink,
This is because the ink easily leaks.

The thin layer of the porous body having a low pore number density is inserted into the lower end of the porous body inside the ink cylinder. The pore number density of the thin layer of such a porous body must be significantly lower than the pore number density of the upper porous body in direct contact, but not necessarily the pore number density of other porous bodies that do not directly contact. There is no need to lower it.

At this time, when a porous body having an extremely low pore number density is used, when the amount of ink contained in the porous body is very small, a negative pressure is hardly formed inside the ink. Therefore, even when the amount of the ink contained in the porous body is very small, a negative pressure is formed inside the ink, so that the pore number density of the thin layer porous body is not too low. It is preferable to form a negative pressure inside the ink even when the amount of ink contained in the porous body is very small, and to reduce the amount of bubbles flowing into the ink supply unit. The pore number density of the thin layer of the porous body is 70 to 120 ppi.

When the thickness of the thin layer of the porous material having a low pore number density is large, the negative pressure suddenly decreases as the amount of the ink contained in the porous material decreases. Therefore, a thin layer of a porous material having a low pore number density prevents the negative pressure from suddenly decreasing by reducing the thickness. If the thin layer of porous material with low pore number density has the appropriate thickness,
Even if bubbles flow into the porous body, they rise due to buoyancy. Therefore, the air bubbles are unlikely to pass through the interface between the porous body having a high pore number density and the porous body having a low pore number density.

In the ink supply device for an ink jet printer as described above, the ink contained in the ink cylinder comes into contact with air at atmospheric pressure through an exhaust port. At this time, a negative pressure lower than the atmospheric pressure is formed inside the ink due to the surface tension of the ink, and the ink moves by capillary action.

The thin layer of porous material having a low pore number density always contains ink because it is located just above the ink supply. Since the pore number density of the thin layer of the porous body is low, an ink flow path connected to the thin layer of the porous body is formed in the entire porous body, and the ink far from the ink supply unit also flows through the ink flow path. Inhaled into the road. Therefore, the flow of ink supplied to the recording apparatus via the ink supply unit is much smoother.

The thin layer of the porous material having a low pore number density is particularly effective when the flow of the ink is fast, because there is no ink flow path and only the ink around the ink supply section is used. Before the ink is first discharged and the ink in the distant portion reaches the ink supply unit, the air cuts off the flow of the ink and prevents the ink from entering the ink supply unit.

Further, since the size of the pores in the thin layer of the porous body is much larger than the size of the pores of the porous body located above, even if bubbles flow into the porous body, they rise due to buoyancy. On the other hand, it is difficult to pass through a boundary between a porous body having a high pore number density and a porous body having a low pore number density. Even if air bubbles pass through the interface between a porous body having a high pore number density and a porous body having a low pore number density, they do not penetrate into the porous body having a low pore number density and have a high pore number density. Attaches to body side. Therefore, the amount of bubbles flowing into the ink supply unit is reduced, and as a result, the amount of bubbles flowing into the recording apparatus is also reduced.

Further, according to the present invention, there is provided an ink cylinder, a porous body, a recording apparatus, an ink supply section, a structure, a rib member, a thin layer of a porous body, a filter, and an exhaust port. Have.

Also in this case, it is preferable to use a porous body having a pore number density of 80 to 200 ppi (pores per inch) for the porous body mounted inside the ink cylinder, for the reason described above.

In the ink supply apparatus of this configuration, a porous body having a certain density of pores is mounted inside the ink cylinder, and the structure formed between the ink supply unit and the porous body and the ink Since the rib members arranged on the upper surface inside the cylinder press the porous body around the ink supply unit, the pore number density of the porous body part located around the ink supply unit increases, and the porous body in other parts is increased. It becomes different from the pore number density of the portion.

The thin layer of the porous body having a low pore number density is inserted between the porous body and the structure inside the ink cylinder, and the pore number density of the thin layer of the porous body is in direct contact. It must be significantly lower than the pore number density of the upper porous body. However, when the pore number density of the thin layer of the porous body is excessively low, when the amount of the ink contained in the porous body is extremely small, it is difficult to form a negative pressure inside the ink.

Therefore, when the amount of ink contained in the porous body is very small, a thin layer is formed to form a negative pressure inside the ink cylinder and to reduce the amount of air bubbles flowing into the ink supply section. The pore number density of the porous body is 70
It is preferably set to 120 ppi.

When the thickness of the thin layer of the porous body having a low pore number density is large, the negative pressure suddenly decreases as the amount of the ink contained in the porous body decreases. Therefore, the thin layer of the porous body having a low pore number density is thinned so that the negative pressure does not suddenly decrease even when the amount of ink inside the ink cylinder is small. If the thin layer of the porous body having a low pore number density has an appropriate thickness, even if bubbles flow into the inside of the porous body, the bubbles rise due to buoyancy. And a porous body having a low pore number density.

In the above-described ink supply apparatus for an ink jet printer, the ink contained in the ink cylinder comes into contact with air at atmospheric pressure through an exhaust port. At this time,
Due to the surface tension of the ink, a negative pressure lower than the atmospheric pressure is formed inside the ink, and the ink moves by capillary action.

At this time, the thin layer of the porous body having a low pore number density always contains the ink because it is located immediately above the ink supply section. Since the pore number density of the thin layer of the porous body is low, an ink flow path connected to the thin layer of the porous body is formed in the entire porous body, and the ink far from the ink supply unit also flows through the ink flow path. Inhaled into the road. Therefore, the flow of ink supplied to the recording apparatus via the ink supply unit is much smoother.

In particular, a thin layer of a porous material having a low pore number density may have a phenomenon in which, when the flow of ink is high, there is no ink flow path and only the ink around the ink supply section is used. Before the ink around the unit is discharged and the distant portion of the ink reaches the ink supply unit, the air cuts off the flow of the ink and prevents the ink from entering the ink supply unit.

Further, since the size of the pores in the thin layer of the porous body is much larger than the size of the pores of the porous body located above, even if bubbles flow into the porous body, they rise by buoyancy. On the other hand, it is difficult to pass through a boundary between a porous body having a high pore number density and a porous body having a low pore number density. Even if air bubbles pass through the interface between a porous body having a high pore number density and a porous body having a low pore number density, they do not penetrate into the porous body having a low pore number density and have a high pore number density. Attaches to body side. Therefore, the amount of bubbles flowing into the ink supply unit is reduced, and as a result, the amount of bubbles flowing into the recording apparatus is also reduced.

At this time, it is preferable that the filter is also provided at a connection portion between the ink supply unit and the recording apparatus, and the filter plays a role of separating impurities and bubbles inside the ink passing through the ink supply unit again. . Therefore, the amount of bubbles flowing into the recording device is much smaller.

Further, in order to reduce the amount of bubbles flowing into the recording apparatus, the shape of the ink supply section in the ink supply apparatus of the ink jet printer having the above-described configuration can be modified.

First, an ink supply section having a generally long pipe shape extending in the vertical direction is connected to an upper ink supply section having a large communication cross section and a lower ink supply section having a communication cross section of a general ink supply section. It consists of two parts.

In the case where the ink supply unit is constituted by the two ink supply units, the flow rate of the ink supplied from the ink cylinder to the recording apparatus decreases in the upper ink supply unit having a large communication cross-sectional area. As the ink flow rate is reduced, the air that has flowed into the upper ink supply section in the ink cylinder is
It rises by buoyancy. Since the rising air is isolated on the surface of the filter, the amount of air bubbles flowing into the recording device is further reduced.

It is preferable that the communication cross-sectional area of the upper ink supply section is 3 to 9 times the communication cross-sectional area of the lower ink supply section. If the communication cross-sectional area of the upper ink supply section is less than three times the communication cross-sectional area of the lower ink supply section, a reduction in flow velocity cannot be expected so much, and it is difficult to obtain an air removing effect. On the other hand, when the communication cross-sectional area of the upper ink supply section exceeds 9 times the communication cross-sectional area of the lower ink supply section, the flow velocity in the upper part is excessively reduced, so that air must be removed at a high flow velocity. Even during the maintenance process, the flow velocity is excessively reduced, so that air cannot be removed so much.

At this time, since the direction of the buoyancy acting on the bubble is the same as the direction of the upper ink supply section having a large communication cross-sectional area, the communication length of the upper ink supply section having a large communication cross-section needs to be increased. There is no.

As the amount of air isolated on the surface of the filter increases, the air is removed using the fast flow rate during the maintenance process. To this end, the flow velocity must not be excessively reduced during the maintenance process, and the communication cross-sectional area of the upper ink supply section should not be too large.

When the air is discharged, the connection between the upper ink supply section and the lower ink supply section is prevented in order to prevent the air from being isolated at the corner of the upper ink supply section due to a sudden change in the communication cross-sectional area. It is preferable that the portion adopts a curve that is slower than a right angle. In particular, in the case of the separation type ink supply device, such a curve processing is necessary in order to completely remove a lot of air flowing in at the time of mounting after the ink cylinder is separated.

Next, the vertically extending tube-shaped ink supply portion is transformed into three steps, and the ink supply portion of the ink supply device is made to have the same communication cross-sectional area as that of a general ink supply portion. And a horizontal ink supply section having a large communication cross-sectional area.

In this embodiment, when the length of the ink supply section in the vertical direction is short and there is no room for deformation in such a state, the ink supply section is connected in the horizontal direction and the ink supply pipe is deformed stepwise. The communication cross-sectional area of the ink supply portion in the horizontal direction is changed.

Also at this time, the ink is supplied from the ink cylinder to the recording apparatus via the ink supply unit, and a filter is arranged between the ink cylinder and the ink supply unit to remove impurities and bubbles contained in the ink. Is prevented from flowing into the recording apparatus to some extent. However, the bubbles that have passed without being separated by the filter flow into the ink supply unit.

The flow velocity of the ink decreases in the horizontal ink supply section having a large communication cross-sectional area, and the bubbles contained in the ink rise due to the buoyancy and collect at the upper portion of the horizontal ink supply section. The air bubbles collected at the upper end of the horizontal ink supply unit are discharged at a high speed during the maintenance process.

At this time, it is preferable that the communication sectional area of the horizontal ink supply section is 3 to 5 times the communication sectional area of the vertical ink supply section. When the communication cross-sectional area of the horizontal ink supply section is less than three times the communication cross-section of the vertical ink supply section, it is difficult to obtain the air removal effect. In addition to the possibility that a large amount of air flows in, there is a problem that air bubbles collected at an upper portion of the ink supply unit are difficult to be removed in a maintenance process.

As described above, when the air is discharged, the horizontal ink supply portion and the vertical ink supply portion are connected so that the air is not isolated at the corners of the horizontal ink supply portion due to a sudden change in the communication sectional area. It is preferable that the connection part with the supply part is processed into a curve.

In particular, in the case of the separation type ink supply device, such a curve processing is necessary in order to completely remove a lot of air flowing in at the time of mounting after the ink cylinder is separated.

However, unlike the case where the communication cross-sectional area of the ink supply section extending in the vertical direction is changed, the horizontal ink supply section has a horizontal direction in which the tube extends and a direction in which ink flows. Since the direction perpendicular to the direction in which buoyancy acts, the communication length of the horizontal ink supply section is made sufficiently long so that air contained in the ink gathers at the upper end of the horizontal ink supply section.

Further, it is preferable that the upper end portion of the horizontal ink supply section is subjected to a hydrophilic treatment so that bubbles are well adhered to the ink supply section. As the method of performing the hydrophilic treatment, several methods such as chemical treatment and gold plating are used.

When the amount of air isolated at the upper end of the horizontal ink supply portion increases, the air is removed by using the high flow velocity during the maintenance process.

Next, an embodiment of the present invention will be described in more detail. However, the following embodiments illustrate the present invention and do not limit the scope of the invention.

First, the ink supply device of the ink jet printer according to the embodiment shown in FIG. 4 will be described.

As shown in FIG. 4, porous bodies 11, 12, and 13 are mounted inside an ink cylinder 10 containing ink. The porous bodies 11, 12, and 13 are composed of a plurality of layers having different pore number densities.
Are stacked in such a manner that the pore number density becomes higher as approaching. At the lower ends of the porous bodies 11, 12, and 13, a thin layer 14 of a porous body having a pore number density lower than that of the porous body 13 which is in direct contact is inserted to smooth the flow of ink, and recording is performed. Prevents air bubbles from flowing into the device.

An ink supply unit 15 is connected to the lower part of the ink cylinder 10 to connect the porous bodies 11, 12, 13, 14 with each other.
Is supplied to the recording device 16. A filter 18 is disposed at a connection portion between the ink cylinder 10 and the ink supply unit 15 to remove impurities and bubbles contained in the ink flowing from the ink cylinder 10 to the ink supply unit 15.

A recording device 16 is connected to the lower end of the ink supply unit 15, and performs recording by ejecting ink supplied from the ink supply unit 15 through nozzles. Further, an exhaust port 17 is formed in the upper part of the ink cylinder 10, and a negative pressure is formed inside the ink by making the ink inside the ink cylinder 10 come into contact with air.

Next, an ink supply device for an ink jet printer according to another embodiment of the present invention shown in FIG. 5 will be described.

As shown in FIG. 5, porous bodies 21, 22, and 23 are mounted inside an ink cylinder 20 containing ink. The porous bodies 21, 22, and 23 are composed of a plurality of layers having different pore number densities.
Are stacked in such a manner that the pore number density becomes higher as approaching. A thin layer 24 of a porous body having a lower pore number density than that of the porous body 23 which is in direct contact with the lower end of the porous bodies 21, 22, 23 is inserted to smooth the flow of ink, thereby recording. Prevents air bubbles from flowing into the device.

An ink supply unit 25 is connected to a lower portion of the ink cylinder 20 to connect the porous bodies 21, 22, 23, 24 with each other.
Is supplied to the recording device 26. A filter 28 is disposed at a connection portion between the ink cylinder 20 and the ink supply unit 25 to remove impurities and bubbles contained in the ink flowing from the ink cylinder 20 to the ink supply unit 25. A recording device 26 is connected to a lower end of the ink supply unit 25, and performs recording by ejecting ink supplied from the ink supply unit 25 through a nozzle.

Another filter 28a is provided between the ink supply unit 25 and the recording device 26 to remove impurities and bubbles remaining without being removed inside the ink passing through the ink supply unit 25 again. I do. An exhaust port 27 is formed in the upper part of the ink cylinder 20 so that
A negative pressure is formed inside the ink by exposing the ink inside to the air.

Next, an ink supply device for an ink jet printer according to another embodiment of the present invention shown in FIG. 6 will be described.

As shown in FIG. 6, porous bodies 31, 32, and 33 are mounted inside an ink cylinder 30 containing ink. The porous bodies 31, 32, and 33 are composed of a plurality of layers having different pore number densities.
Are stacked in such a manner that the pore number density becomes higher as approaching. At the lower ends of the porous bodies 31, 32, and 33, a thin layer 34 of a porous body having a pore number density lower than the pore number density of the porous body 33 which is in direct contact is inserted to smooth the flow of ink, and recording is performed. Prevents air bubbles from flowing into the device.

An ink supply unit 35 is connected to a lower portion of the ink cylinder 30 to connect the porous bodies 31, 32, 33, and 34.
Is supplied to the recording device 36. At this time, the ink supply section 35 extends in the vertical direction and is composed of two parts, an upper ink supply section 35a having a large communication cross-sectional area and a lower ink supply section 35b having a general ink supply section. Make a shape. Since the ink supplied from the ink cylinder 30 to the recording device 36 has a reduced flow velocity in the upper ink supply part 35a having a large communication cross-sectional area, the air flowing from the ink cylinder into the upper ink supply part 35a rises by buoyancy. I do. Since the raised air is isolated on the surface of the filter 38, the amount of bubbles flowing into the recording device 36 is further reduced.

The ink cylinder 30 and the ink supply unit 35
A filter 38 is disposed at the connection portion with the ink cylinder 3.
Impurities and bubbles contained in the ink flowing from 0 to the ink supply unit 35 are removed. A recording device 36 is connected to a lower end of the ink supply unit 35, and performs recording by ejecting ink supplied from the ink supply unit 35 through a nozzle. An exhaust port 37 is formed in the upper part of the ink cylinder 30 to make the ink inside the ink cylinder 30 come into contact with air, thereby forming a negative pressure inside the ink.

Next, an ink supply device for an ink jet printer according to another embodiment of the present invention shown in FIG. 7 will be described.

As shown in FIG. 7, porous bodies 41, 42 and 43 are mounted inside an ink cylinder 40 containing ink. The porous bodies 41, 42, and 43 are composed of a plurality of layers having different pore number densities.
Are stacked in such a manner that the pore number density becomes higher as approaching. At the lower ends of the porous bodies 41, 42, and 43, a thin layer 44 of a porous body having a pore number density lower than that of the porous body 43 which is in direct contact is inserted to smooth the flow of ink and record. It prevents bubbles from flowing into the device.

An ink supply unit 45 is connected to a lower portion of the ink cylinder 40, and is connected to the porous bodies 41, 42, 43, and 44.
Is supplied to the recording device 46. At this time, the ink supply unit 45 includes three portions 45a and 45
b, 45c, and a horizontal portion of the ink supply section 45
b increases the communication cross-sectional area and lengthens the communication length. In the horizontal ink supply section 45b having a large communication cross-sectional area, the flow velocity of the ink decreases, and the bubbles contained in the ink rise due to buoyancy and collect at the upper end of the horizontal ink supply section 45b. The amount of air bubbles flowing into 46 is further reduced.

The ink cylinder 40 and the ink supply unit 45
A filter 48 is arranged at the connection portion of the ink cylinder 40.
The impurities and bubbles contained in the ink flowing into the ink supply unit 45 from the ink are removed. The ink supply unit 45
A recording device 46 is connected to a lower end of the recording medium, and performs recording by ejecting ink supplied from the ink supply unit 45 through a nozzle. An exhaust port 47 is formed in the upper part of the ink cylinder 40 so that the ink inside the ink cylinder 40 comes into contact with air to create a negative pressure inside the ink.

Next, an ink supply device for an ink jet printer according to another embodiment of the present invention shown in FIG. 8 will be described.

As shown in FIG. 8, a porous body 51 having a constant pore number density is mounted inside an ink cylinder 50 containing ink. On the upper surface inside the ink cylinder 50,
A rib member 53 for holding down the porous body 51 around the ink supply unit 55 and increasing the pore number density in that part is arranged. A structure 54 that presses the porous body 51 around the ink supply unit 55 and increases the number density of pores in that part is disposed on the ink supply unit 55 side inside the ink cylinder 50.

Between the porous body 51 and the structure 54, a thin layer 52 of a porous body having a pore number density significantly lower than the pore number density of the porous body 51 in direct contact is inserted. The flow of the ink is made smooth, and bubbles are prevented from flowing into the recording apparatus.

An ink supply unit 55 is connected to a lower portion of the ink cylinder 50 to supply the ink contained in the porous bodies 51 and 52 to the recording device 56. A filter 57 is disposed at a connection portion between the ink cylinder 50 and the ink supply unit 55 to remove impurities and bubbles contained in the ink flowing into the ink supply unit 55 from the ink cylinder 50. A recording device 56 is connected to a lower end of the ink supply unit 55, and performs recording by ejecting ink supplied from the ink supply unit 55 through a nozzle. An exhaust port 58 is formed in the upper part of the ink cylinder 50 so that the ink inside the ink cylinder 50 comes into contact with air to form a negative pressure inside the ink.

Next, an ink supply device for an ink jet printer according to another embodiment of the present invention shown in FIG. 9 will be described.

As shown in FIG. 9, a porous body 61 having a constant pore number density is mounted inside an ink cylinder 60 containing ink. On the upper surface inside the ink cylinder 60,
A rib member 63 for holding down the porous body 61 around the ink supply section 65 and increasing the pore number density at that portion is arranged. In addition, a structure 64 that presses the porous body 61 around the ink supply unit 65 and increases the pore number density in that portion is arranged on the ink supply unit 65 side inside the ink cylinder 60.

Between the porous body 61 and the structure 64, a thin layer 62 of a porous body having a pore number density significantly lower than the pore number density of the porous body 61 in direct contact is inserted. The flow of the ink is made smooth, and bubbles are prevented from flowing into the recording apparatus.

An ink supply section 65 is connected to a lower portion of the ink cylinder 60 to supply the ink contained in the porous bodies 61 and 62 to the recording device 66. A filter 67 is disposed at a connection portion between the ink cylinder 60 and the ink supply unit 65 to remove impurities and bubbles contained in the ink flowing from the ink cylinder 60 to the ink supply unit 65. A recording device 66 is connected to a lower end of the ink supply unit 65, and performs recording by ejecting ink supplied from the ink supply unit 65 through a nozzle.

Another filter 67a is provided between the ink supply unit 65 and the recording device 66 to remove impurities and bubbles remaining without being removed inside the ink that has passed through the ink supply unit again. . The ink cylinder 6
An exhaust port 68 is formed in the upper part of the ink tank 60 so that the ink inside the ink cylinder 60 is brought into contact with air to form a negative pressure inside the ink.

Next, an ink supply device for an ink jet printer according to another embodiment of the present invention shown in FIG. 10 will be described.

As shown in FIG. 10, a porous body 71 having a constant pore number density is mounted inside an ink cylinder 70 containing ink. On the upper surface inside the ink cylinder 70, a porous body 71 around the ink supply unit 75 is pressed,
A rib member 73 for increasing the pore number density in that portion is arranged. Also, on the ink supply unit 75 side inside the ink cylinder 70, a porous body 71 around the ink supply unit 75 is pressed,
A structure 74 for increasing the pore number density at that portion is arranged.

Between the porous body 71 and the structure 74, a thin layer 72 of a porous body having a pore number density significantly lower than the pore number density of the porous body 71 in direct contact is inserted. The flow of the ink is made smooth, and bubbles are prevented from flowing into the recording apparatus.

An ink supply section 75 is connected to a lower portion of the ink cylinder 70 to supply the ink contained in the porous bodies 71 and 72 to the recording device 76. At this time, the ink supply unit 75 extends in the vertical direction and includes two parts, an upper ink supply part 75a having a large communication cross-sectional area and a lower ink supply part 75b having a general ink supply part. Make a shape. From the ink cylinder 70 to the recording device 7
Since the ink supplied to 6 has a lower flow velocity in the upper ink supply portion 75a having a large communicating cross-sectional area, the air flowing from the ink cylinder into the upper ink supply portion 75a rises by buoyancy. Since the raised air is isolated on the surface of the filter 78, the amount of air bubbles flowing into the recording device 76 is further reduced.

The ink cylinder 70 and the ink supply unit 75
A filter 77 is arranged at the connection portion with the ink cylinder 7.
Impurities and bubbles contained in the ink flowing from 0 to the ink supply unit 75 are removed. A recording device 76 is connected to a lower end of the ink supply unit 75, and performs recording by ejecting ink supplied from the ink supply unit 75 through a nozzle. An exhaust port 78 is formed in the upper part of the ink cylinder 70 to make the ink inside the ink cylinder 70 come into contact with air to form a negative pressure inside the ink.

Next, an ink supply device for an ink jet printer according to another embodiment of the present invention shown in FIG. 11 will be described.

As shown in FIG. 11, a porous body 81 having a constant pore number density is mounted inside an ink cylinder 80 containing ink. On the upper surface inside the ink cylinder 80, a porous body 81 around the ink supply unit 85 is pressed,
A rib member 83 for increasing the number density of pores in that portion is arranged. Also, on the ink supply unit 85 side inside the ink cylinder 80, a porous body 81 around the ink supply unit 85 is pressed,
A structure 84 for increasing the pore number density at that portion is arranged.

Between the porous body 81 and the structure 84, a thin layer 82 of a porous body having a pore number density significantly lower than the pore number density of the porous body 81 in direct contact is inserted. The flow of the ink is made smooth, and bubbles are prevented from flowing into the recording apparatus.

An ink supply section 85 is connected to a lower portion of the ink cylinder 80 to supply the ink contained in the porous bodies 81 and 82 to the recording device 86. At this time, the ink supply section 85 is formed in three steps 85a, 85b, and 85c in a stepwise manner, and the horizontal ink supply section 85b has a larger communication cross-sectional area and a longer communication length. In the horizontal ink supply portion 85b having a large communication cross-sectional area, the flow velocity of the ink decreases, and bubbles contained in the ink rise due to buoyancy and collect at the upper end of the horizontal ink supply portion 85b. The amount of bubbles flowing into 86 is further reduced.

The ink cylinder 80 and the ink supply unit 85
A filter 87 is disposed at the connecting portion of
The impurities and bubbles contained in the ink flowing into the ink supply unit 85 from the ink are removed. The ink supply unit 8
A recording device 86 is connected to the lower end of the recording medium 5, and the recording is performed by ejecting the ink supplied from the ink supply unit 85 through a nozzle. An exhaust port 88 is formed in the upper part of the ink cylinder 80 so that the ink inside the ink cylinder 80 comes into contact with air to form a negative pressure inside the ink.

[0105]

As described above in detail, according to the ink supply device of the ink jet printer described in each claim, a porous material having a low pore number density is provided between the porous material having a high pore number density and the ink supply section. By increasing the use of ink contained inside the porous body having a high pore number density by inserting a thin layer of the porous body, it becomes possible to reduce the amount of unused ink and remaining ink. Further, since the ink flow path is formed entirely in the porous body having a low pore number density, the ink is more smoothly supplied from the ink supply device to the recording device.

Further, since the amount of bubbles flowing into the recording apparatus is reduced, it is possible to reduce errors in the operation of the recording apparatus caused by the bubbles flowing into the recording apparatus.

Further, since the amount of air flowing into the recording apparatus is reduced, the size of the pores of the filter can be adjusted not to the size of bubbles but to the size of impurities that need to be separated. Therefore, the pores can be made larger than in the conventional filter, so that the flow of the ink, which tends to be harmed by the very small pores of the filter, is smoothed.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating an ink supply device of a conventional inkjet printer.

FIG. 2 is a sectional view showing an ink supply device of another conventional inkjet printer.

FIG. 3 is an exploded perspective view showing a recording apparatus connected to an ink supply unit.

FIG. 4 is a sectional view showing an ink supply device of the inkjet printer according to one embodiment of the present invention.

FIG. 5 is a cross-sectional view illustrating an ink supply device of an inkjet printer according to another embodiment of the present invention.

FIG. 6 is a cross-sectional view illustrating an ink supply device of the inkjet printer according to one embodiment of the present invention.

FIG. 7 is a cross-sectional view illustrating an ink supply device of the inkjet printer according to one embodiment of the present invention.

FIG. 8 is a sectional view showing an ink supply device of the inkjet printer according to one embodiment of the present invention.

FIG. 9 is a cross-sectional view illustrating an ink supply device of the inkjet printer according to one embodiment of the present invention.

FIG. 10 is a cross-sectional view illustrating an ink supply device of the inkjet printer according to one embodiment of the present invention.

FIG. 11 is a cross-sectional view illustrating an ink supply device of the inkjet printer according to one embodiment of the present invention.

[Explanation of symbols]

10, 20, 30, 40, 50, 60, 70, 80
Ink cylinders 11, 12, 13, 21, 22, 23, 31, 32, 3
3, 41, 42, 43, 51, 61, 71, 81 Porous body 14, 24, 34, 44, 52, 62, 72, 82
Thin layer of porous body 15, 25, 35, 45, 55, 65, 75, 85
Ink supply unit 16, 26, 36, 46, 56, 66, 76, 86
Recording device 17, 27, 37, 47, 57, 67, 77, 87
Exhaust port 18, 28, 38, 48, 58, 68, 78, 88
Filters 53, 63, 73, 83 Rib members 54, 64, 74, 84 Structure

Claims (20)

(57) [Claims] An ink-containing ink cylinder and a layer having a different pore number density are stacked so as to increase the pore number density as approaching an ink supply section, and are mounted inside the ink cylinder to contain the ink. A porous body, a thin layer of a porous body that is inserted at the lower end of the porous body inside the ink cylinder and has a pore number density lower than the pore number density of the porous body that directly contacts, and a lower part of the ink cylinder. An ink supply unit connected to supply the ink contained in the porous body to the recording apparatus, a filter arranged at a connection portion between the ink cylinder and the ink supply unit, and the supplied ink passes through a nozzle. A recording device for recording by being ejected and ejected, and an exhaust port formed at the top of the ink cylinder to form a negative pressure inside the ink by bringing the ink inside the ink cylinder into contact with air. An ink supply device for an ink jet printer, wherein the flow of ink flowing into a recording device via an ink supply unit is smooth, and bubbles are prevented from flowing into the recording device. 2. The ink supply device according to claim 1, wherein the thin layer of the porous body having a low pore number density has a pore number density of 70 to 120 ppi. 3. The ink supply device for an ink jet printer according to claim 1, wherein a filter is further provided at a connection portion between the ink supply unit and the recording device. 4. The ink supply unit according to claim 1, wherein the ink supply unit has a tube shape extending in a vertical direction, and a communication cross-sectional area of an upper portion of the ink supply unit is larger than a communication cross-sectional area of a lower portion of the ink supply unit. Ink supply device for inkjet printer. 5. The ink supply device for an ink jet printer according to claim 4, wherein a communication cross-sectional area of an upper portion of said ink supply portion is 3 to 9 times a communication cross-sectional area of a lower portion of said ink supply portion. 6. The ink jet printer according to claim 4, wherein a connecting portion between an upper portion of the ink supply section having the larger communication cross-sectional area and a lower portion having the smaller communication cross-sectional area is formed in a curved shape. Ink supply device. 7. The ink supply unit according to claim 1, wherein the ink supply unit has a vertical section and a horizontal section, and the horizontal section of the ink supply section has a large communication sectional area and a long communication length. Item 2. An ink supply device for an ink jet printer according to item 1. 8. An ink supply device for an ink jet printer according to claim 7, wherein a communication sectional area of a horizontal portion of said ink supply portion is 3 to 5 times a communication sectional area of a vertical portion. 9. The ink supply device according to claim 7, wherein a connecting portion between the horizontal portion and the vertical portion of the ink supply unit is formed in a curved shape. 10. An ink supply apparatus for an ink jet printer according to claim 7, wherein an upper end portion of a horizontal portion of said ink supply section is subjected to a hydrophilic treatment. 11. An ink cylinder containing ink, a porous body mounted inside the ink cylinder to contain the ink, and a recording device connected to the ink cylinder and recording by ejecting the ink. An ink supply unit connected to a lower portion of the ink cylinder and supplying ink contained in the porous body to a recording apparatus; and an ink supply unit for increasing the number density of pores on the ink supply unit side of the porous body. A rib arranged on the upper surface inside the ink cylinder in order to increase the number density of pores on the ink supply unit side of the porous body; and the ink of the porous body inside the ink cylinder. A thin layer of a porous body that is inserted between a lower end portion on a supply unit side and the structure body and has a pore number density lower than the pore number density of the porous body; and a connection portion between the ink cylinder and the ink supply unit. Located at And a discharge port formed at an upper portion of the ink cylinder to form a negative pressure inside the ink by bringing the ink inside the ink cylinder into contact with air, and a recording apparatus through the ink supply unit from the ink cylinder. The flow of ink flowing into the
An ink supply device for an ink jet printer, which prevents air bubbles from flowing into a recording device. 12. The ink supply device according to claim 11, wherein the thin layer of the porous body having a low pore number density has a pore number density of 70 to 120 ppi. 13. The ink supply device for an ink jet printer according to claim 11, wherein a filter is further disposed at a connection portion between the ink supply unit and the recording device. 14. The ink supply section according to claim 11, wherein the ink supply section has a tubular shape extending in a vertical direction, and a communication cross-sectional area of an upper portion of the ink supply section is larger than a communication cross-sectional area of a lower portion thereof. Ink supply device for inkjet printer. 15. The ink supply device according to claim 14, wherein a communication cross-sectional area of an upper part of the ink supply part is 3 to 9 times a communication cross-sectional area of a lower part of the ink supply part. 16. The ink-jet printer according to claim 14, wherein a connecting portion between an upper portion of the ink supply section having the large communication cross-sectional area and a lower portion having the small communication cross-sectional area is formed in a curved shape. Ink supply device. 17. The ink supply unit according to claim 1, wherein the ink supply unit has a vertical cross section and a horizontal cross section, and the horizontal cross section of the horizontal section of the ink supply section is large and the communication length is long. Item 12. An ink supply device for an ink jet printer according to item 11. 18. The ink supply apparatus according to claim 17, wherein a communication cross-sectional area of a horizontal portion of the ink supply section is 3 to 5 times a communication cross-sectional area of a vertical portion. 19. The ink supply device according to claim 17, wherein a connecting portion between the horizontal portion and the vertical portion of the ink supply unit is formed in a curved shape. 20. The ink supply device for an ink jet printer according to claim 17, wherein an upper end portion of the horizontal portion of the ink supply unit is subjected to a hydrophilic treatment.