JP2000296625A - Ink jet recording apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ink jet recording apparatus capable of simply removing air accumulated in a sub-tank. SOLUTION: In an ink jet recording head having an ink jet recording element 7, a sub-tank 3 for pooling ink and an ink feed pipe 8 feeding ink to the ink jet recording element 7 from the sub-tank 3, the ink feed pipe 8 is projected into the sub-tank 3 and a meniscus forming part is provided to the side surface of the projected part of the ink feed pipe 8.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an ink jet recording apparatus, and more particularly to an ink jet recording apparatus for printing data created by a personal computer or the like.

[0002]

2. Description of the Related Art As one of conventional recording apparatuses, an ink tank is fixedly provided on an apparatus main body, and ink is supplied by a tube to an ink jet recording head on a carriage that performs a scanning operation. An apparatus is disclosed in, for example, Japanese Patent Application Laid-Open No. 10-128993.

FIG. 13 is a schematic view showing an example of such a conventional ink jet recording apparatus. In an ink jet recording apparatus 10, an ink jet recording head 2 is mounted on a shaft 12 fixed to chassis 11A and 11B. The carriage 13 alternately scans (main scan) in the direction of arrow 17 in the figure to perform ink jet recording on the recording medium 14, and the recording medium 14 is transported by rollers 15 in a direction perpendicular to the paper surface (sub-scan). It is configured to be. Such an ink jet recording apparatus 1
0, the ink flow path is
The ink is supplied to the ink jet recording head 2 from the main ink tank 1 fixed at 0 through the tube 4. The main ink tank 1 is a consumable that is replaced when the ink becomes empty. Further, the recovery process is performed by cleaning the inkjet recording head 2 by the suction recovery unit 16.

FIG. 14 is a view for explaining an ink supply system in such a conventional ink jet recording apparatus. A main ink tank 1 for supplying ink is provided with:
It is made of a soft and sealable material such as a vinyl pack, and is attached and fixed to the apparatus main body side of the ink jet recording apparatus 10. The ink jet recording head 2 is mounted on a carriage 13 that scans on a recording medium 14 to perform recording. Ink is temporarily pooled in the sub tank 3 in the ink jet recording head 2, and the main ink tank 1 and the sub tank 3 An ink flow path is formed between them. The sub tank 3 and the main ink tank 1 are connected to the tube 4 at joints 5A and 5B so as to be freely connected to each other. Actually, the ink is applied to the recording medium 14.
The ink jet recording element 7 that discharges ink to the printer comprises a driving unit and a nozzle, and the driving unit comprises a piezo element and a heater. Further, ink is supplied from the sub tank 3 to the ink jet recording element 7 via an ink supply pipe 8.

Next, the operation of such an ink jet recording apparatus will be described with reference to FIGS.
FIG. 15 shows the state of the ink before the main ink tank 1 and the inkjet recording head 2 are mounted on the recording apparatus main body. The main ink tank 1 is sealed in a state where the ink is full, and contains no gas bubbles. Similarly, the ink jet recording head 2 is fully filled with ink in the manufacturing process, and contains no gas bubbles. The tube 4 attached to the main body of the recording apparatus has joint portions 5A and 5B open, respectively, does not contain ink, and is filled with air.

[0006] From such a state of the main ink tank 1 and the ink jet recording head 2, the joint portion 5A,
FIG. 16 shows that the tube 4 and the main ink tank 1 and the tube 4 and the ink jet recording head 2 are connected in 5B. In this state, no ink moves. When the printing operation is actually started from this state as shown in the figure, ink is ejected onto the recording medium 14 via the recording element 7, and as a result, the inside of the sub tank 3 becomes negative with respect to the atmospheric pressure. Pressure.

On the other hand, although the main ink tank 1 is sealed, the main ink tank 1 is made of a soft material such as a vinyl pack, and the ink inside is always under atmospheric pressure. Flows from the main ink tank 1 to the sub tank 3 via the tube 4. Along with this, the air that has been in the tube 4 accumulates in the upper part in the sub tank 3. Therefore, the entire shape of the main ink tank 1 is naturally collapsed by the volume of the flow of the ink.

FIG. 14 shows this state. The volume V 0 of air in the sub tank 3 is substantially equal to the volume of the tube 4. Thereafter, when printing is further continued, the ink is supplied from the main ink tank 1 to the tube 4 by the same process.
Flows to the sub-tank 3 via. Then, since the ink flows from the lower part of the sub-tank 3 to the ink supply pipe, the air volume V0 in the upper part in the sub-tank 3 does not change.

However, when the printer, that is, the ink jet recording apparatus 10 is left for a long period of time, gas enters the ink flow path through the tube wall of the tube 4 and the joints 5A and 5B, and bubbles are generated. 28 and 29 are formed. FIG. 17 shows the state. Such bubbles 28 and 29 are eventually accumulated in the sub-tank 3, and as shown in FIG. 18, the inside of the sub-tank 3 is completely occupied by gas. In this case, stable supply of ink from the tube 4 to the sub-tank 3 is no longer possible, and the ink jet recording head 2 itself becomes inoperable. In order to avoid such a situation, it is necessary to increase the internal volume of the sub-tank 3 in accordance with other durability performances such as the life of the heater. Therefore, if it is attempted to guarantee a remarkable durability with a permanent head or the like, the size of the sub-tank 3 becomes larger, and the size of the printer itself becomes larger than necessary.

[0010] Alternatively, Japanese Patent Application Laid-Open No. H10-128993
As described in Japanese Patent Application Laid-Open Publication No. H10-157, there is a means for suppressing gas intrusion into the ink flow path by pressurizing the tube, but such means is complicated and the system itself becomes expensive. .

[0011]

The accumulation of gas in the sub-tank 3 as described above is performed by the suction recovery unit 16 as shown in FIG. 18 in the direction of the arrow in FIG. , Only the ink at the lower part of the sub tank 3 is sucked,
The gas in the upper part of the sub tank 3 cannot be removed.

Accordingly, an object of the present invention is to solve the above-mentioned conventional problems, and an object of the present invention is to provide an ink jet recording apparatus capable of easily removing gas accumulated in a sub tank.

[0013]

In order to achieve the above object, an ink jet recording apparatus according to the present invention supplies an ink jet recording element, a sub-tank for pooling ink, and supplies ink to the ink jet recording element from the sub-tank. An ink jet recording head having an ink supply tube, a main ink tank, and an ink supply unit that supplies ink from the main ink tank to the sub tank, wherein the ink supply tube protrudes into the sub tank; A meniscus forming portion is provided on the side surface of the projecting portion.

In the ink jet recording apparatus according to the present invention, the meniscus forming portion is formed in a nozzle shape.

Further, the ink jet recording apparatus of the present invention is characterized in that the meniscus forming portion is formed in a slit shape.

Further, in the ink jet recording apparatus according to the present invention, at least a part of the ink supply pipe is made of a porous material.

An ink jet recording apparatus according to the present invention is characterized in that the porous material is a material obtained by compression molding fibers.

The ink jet recording apparatus according to the present invention is characterized in that at least a part of the ink supply pipe is a mesh.

Further, the ink jet recording apparatus of the present invention is characterized in that the ink jet recording head has the ink jet recording element connected to the ink supply pipe.

Still further, the ink jet recording apparatus of the present invention is characterized in that a suction recovery unit is brought into close contact with the ink jet recording head to perform a suction recovery process.

[0021] The ink jet recording apparatus of the present invention is characterized in that the ink jet recording head has an electrothermal converter for generating thermal energy used for discharging ink.

Further, the ink jet recording apparatus of the present invention is characterized in that the electrothermal transducer generates electric energy which causes film boiling of the ink.

In the present specification, the term “record” (hereinafter also referred to as “record”) refers not only to the formation of significant information such as characters and figures, but also to significant or insignificant information. Regardless of whether or not the image is visualized so that a human can perceive it visually, the case where an image, a pattern, a pattern, or the like is widely formed on a recording medium or the medium is processed is also referred to.

Here, the term "recording medium" refers not only to paper used in a general recording apparatus but also broadly, a cloth, a plastic film, a metal plate, or any other material capable of accepting ink.

Further, "ink" should be interpreted broadly as in the definition of "recording" described above. When applied to a recording medium, it forms an image, a pattern, a pattern, or processes the recording medium. Liquid that can be provided to

In this specification, the term nozzle generally refers to a discharge port, a liquid path communicating with the discharge port, and an element that generates energy used for ink discharge, unless otherwise specified.

[0027]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the ink jet recording apparatus according to the present invention, the ink jet recording element, a sub-tank for pooling ink, and an ink supply pipe for supplying ink from the sub-tank to the ink jet recording element are provided. In the ink jet recording head having the above, the ink supply pipe protrudes into the sub-tank, and various types of meniscus forming portions are provided on side surfaces of the protruding portion, so that air bubbles accumulated in the sub-tank are easily removed by a suction operation. And the capacity of the sub-tank can be reduced, so that the printer body can be made compact.

Hereinafter, embodiments of the ink jet recording apparatus of the present invention will be described in detail with reference to the drawings.

(Embodiment 1) FIG. 1 is a schematic diagram showing the configuration of an ink jet recording apparatus equipped with an ink jet recording head to which the present invention is applied.

As shown in the figure, in an ink jet recording apparatus 10 to which the present invention is applied, a carriage 13 having an ink jet recording head 2 is mounted on a shaft 12 fixed to chassis 11A, 11B in the direction of arrow 17 in FIG. This is a method in which ink jet recording is performed on the recording medium 14 by alternate scanning (main scanning). Such a recording medium 14 is conveyed (sub-scanning) in a direction perpendicular to the paper surface by a roller 15, and the ink flow path is a main ink tank 1 in which ink is fixed to the ink jet recording apparatus 10. And is supplied to the inkjet recording head 2 via a tube 4. Such a main ink tank 1 is a consumable that is replaced when the ink becomes empty. Further, the ink jet recording head 2 is cleaned by the suction recovery unit 16 so that necessary recovery processing is performed.

FIG. 2 is a detailed view showing the ink jet recording head 2 in the ink jet recording apparatus 10 of the present invention. As shown in the figure, a main ink tank 1 for supplying ink is made of a sealable and soft material such as a vinyl pack, and is attached and fixed to the apparatus main body side of the ink jet recording apparatus 10. ing. Further, the inkjet recording head 2 is mounted on a carriage 13 that scans over a recording medium 14 to perform recording, and ink is supplied to the inkjet recording head 2.
Is configured to be temporarily pooled in the sub tank 3. Therefore, the sub-tank 3 and the main ink tank 1 are connected to each other via the joints 5A and 5B so as to be freely connected so that an ink flow path is formed between the main ink tank 1 and the sub-tank 3 by the tube 4. ing. The ink jet recording element 7 that ejects ink to the recording medium 14 includes a driving unit and a nozzle, and the driving unit includes a piezo element and a heater. Ink is supplied from the sub tank 3 to the ink jet recording element 7 via an ink supply pipe 8.

The ink supply tube 8 has a small hole 8A for forming a meniscus with ink as a meniscus forming portion on a side surface of a protruding portion that protrudes into the sub tank 3. The size of the small hole 8A is determined so that the meniscus is not broken even when the water head pressure h of the ink is applied. Therefore, the radius of the small hole 8A must be determined to be larger than the radius r obtained by the following equation.

Ρgh = 2rcos θ / r where ρ: ink density r: ink surface tension
θ: Contact angle r: Small hole radius h: Head pressure

Next, the operation of such an ink jet recording head will be described with reference to FIGS.

FIG. 3 is a view showing a state of the ink jet recording head 2 before being set in the ink jet recording apparatus 10. The ink jet recording head 2 is filled with ink in a manufacturing process and gas bubbles are contained. Not. Although not shown, the main ink tank 1 is also sealed with a full ink as in the conventional example, and contains no gas bubbles. Similarly, although not shown, the tube 4 attached to the apparatus main body of the ink jet recording apparatus also has joints 5A and 5B opened like the conventional example, and is filled with air without ink. From the state of the main ink tank 1 and the ink jet recording head 2, the joint portions 5A, 5B
In FIG. 4, the tube 4 and the main ink tank 1, and the tube 4 and the ink-jet recording head 2 are shown in FIG.

As shown, when printing is started from such a state, ink flows from the main ink tank 1 to the sub-tank 3 via the tube 4 as in the conventional example, and the ink flows from the ink jet recording element 7. The required printing is performed by ejection.

Next, FIG. 5 shows a state in which the ink jet recording apparatus is not used for a long time and is left. In such a state, the tube 4 has bubbles 31 that have entered from the tube wall surface, the joints 5A, 5B, and the like, and the gas 32 also accumulates in the upper part in the sub tank 3.

FIG. 6 is a view showing a state in which gas further accumulates in the sub-tank 3. In such a state, ink cannot flow from the sub-tank 3 to the ink jet recording element 7 at all, and non-ejection occurs. Wake up. At this stage in the conventional example, the ink jet recording head 2 becomes unusable at this stage, but in the present embodiment, the ink jet recording head 2 can be recovered by the suction recovery operation described below, and the ink jet recording head 2 can be reused. Can be.

FIG. 7 is an explanatory diagram of this suction recovery operation.
The suction recovery unit 1 is provided on the nozzle surface of the ink jet recording element 7 of the ink jet recording head 2 to be subjected to the suction recovery processing.
After the close contact of 6, suction is performed in the direction of the arrow by a pump (not shown). As described above, when suction is performed by the pump, first, the gas in the ink supply pipe 8 is exhausted. By the action of the negative pressure generated by this, ink is passed from the main ink tank 1 through the tube 4 to be discharged. It flows into the sub tank 3. When the ink level of the ink flowing into the sub tank 3 reaches the small hole 8A,
As shown in FIG. 8, a meniscus 8B is formed in the small hole 8A. When the suction is further continued, the ink flows from the tube 4 into the sub tank 3 steadily. However, the ink that has flowed into the sub-tank 3 in this manner cannot flow into the ink supply pipe 8 because it is blocked and blocked by the meniscus 8B. Therefore, only gas is still discharged from the inkjet recording head 2 by suction from the suction recovery unit 16. In this manner, only the gas is supplied to the ink tank until the ink flows into the sub-tank 3 and the liquid level of the ink reaches the height of the ink supply pipe 8 as shown in FIG. The ink is discharged from the ink jet recording element 7 through the tube 8.

When suction is further continued from the state of FIG. 9,
The ink flowing from the tube 4 into the sub tank 3 is
The ink flows over the wall surface of the ink supply pipe 8 and flows into the ink supply pipe 8. At this time, as soon as the flowing ink comes into contact with the meniscus 8B of the small hole 8A, the meniscus 8B is destroyed. When the meniscus 8B is destroyed and lost in this manner, since the head pressure h is applied to the small hole 8A, the ink flows into the ink supply pipe 8 from the small hole 8A, and FIG.
It returns to the state of. As a result, the suction recovery operation is completed, and the inkjet recording head 2 is again in a state where recording is possible.

(Embodiment 2) Next, Embodiment 2 of the ink jet recording apparatus according to the present invention will be described. In Embodiment 1 described above, bubbles in the ink jet recording head 2 are selectively discharged by a suction recovery operation. In the second embodiment, the ink supply pipe 8 is provided with a slit 8C as shown in FIG. 10, and a meniscus is formed by the slit 8C. I have.

That is, in the present embodiment, when the ink supply tube 8 is manufactured by molding or the like, in the first embodiment, the mold itself is complicated and precision is required.
If the small holes 8A are replaced with the slits 8C as in the above, only the slits 8C are provided along the ink supply pipe 8, so that the slits 8C can be easily processed, and therefore, mass productivity can be increased with a simple shape. it can.

Embodiment 3 Next, Embodiment 3 of the ink jet recording apparatus according to the present invention will be described. In the third embodiment, as shown in FIG.
Are formed of the porous material 8D. Therefore, since the porous material 8D of the ink supply pipe 8 must pass ink, the porous material 8D must be a porous material in which small holes communicate with each other. In addition, the porous material 8D may be formed by molding, sintering metal, or the like, or may be formed by a material obtained by compression-molding a fiber.

Since such a porous material 8D can be regarded as an aggregate of minute meniscus, the same effect as in the first embodiment can be obtained.

Further, by using the porous material 8D, a function of a filter for removing foreign matters such as dust mixed in the ink can be provided.

(Embodiment 4) Further, Embodiment 4 of the ink jet recording apparatus of the present invention will be described. In the fourth embodiment, as shown in FIG. 12, a part of the ink supply pipe 8 is formed of a mesh material 8E. Such a mesh material 8E is formed by cutting out a part of the ink supply pipe 8 to form a notch, a slot, or the like.
E is attached. Various materials such as metal and plastics can be used for the mesh material 8E. Furthermore, since the mesh material 8E can be regarded as a mass of uniform meniscus,
It is more suitable for high-speed printers with high ink flow speed. Furthermore, since the mesh material 8E has a uniform meniscus as compared with a porous material, stable performance can be obtained, which is preferable. Further, the mesh material 8E can also have a function of a filter capable of removing foreign matters such as dust mixed in the ink, as in the third embodiment.

(Others) It should be noted that the present invention includes a means (for example, an electrothermal converter or a laser beam) for generating thermal energy as energy used for performing ink ejection, particularly in an ink jet recording system. An excellent effect is obtained in a recording head and a recording apparatus of a type in which the state of ink is changed by the thermal energy. This is because according to such a method, it is possible to achieve higher density and higher definition of recording.

The typical configuration and principle are described in, for example, US Pat. No. 4,723,129, and US Pat.
It is preferable to use the basic principle disclosed in 740,796. This method can be applied to both the so-called on-demand type and the continuous type. In particular, in the case of the on-demand type, it is arranged corresponding to the sheet or the liquid path holding the liquid (ink). Applying at least one drive signal corresponding to the recording information and providing a rapid temperature rise exceeding nucleate boiling to the electrothermal transducer, thereby causing the electrothermal transducer to generate thermal energy, thereby causing the recording head to emit heat energy. This is effective because a film in the liquid (ink) corresponding to the driving signal can be formed one by one by causing film boiling on the heat acting surface. The liquid (ink) is ejected through the ejection opening by the growth and contraction of the bubble to form at least one droplet. When the drive signal is formed into a pulse shape, the growth and shrinkage of the bubble are performed immediately and appropriately, so that the ejection of liquid (ink) having particularly excellent responsiveness can be achieved, which is more preferable. As the pulse-shaped drive signal, those described in U.S. Pat. Nos. 4,463,359 and 4,345,262 are suitable. In addition, U.S. Pat. No. 4,313,124 relating to the invention relating to the rate of temperature rise of the heat acting surface.
If the conditions described in the specification are adopted, more excellent recording can be performed.

As the configuration of the recording head, in addition to the combination of the discharge port, the liquid path, and the electrothermal converter (linear liquid flow path or right-angled liquid flow path) as disclosed in the above-mentioned respective specifications, The present invention also includes a configuration using U.S. Pat. No. 4,558,333 and U.S. Pat. No. 4,459,600 which disclose a configuration in which a heat acting portion is arranged in a bending region. It is. In addition, Japanese Unexamined Patent Publication No. Sho 59-123670 discloses a configuration in which a common slit is used as a discharge portion of an electrothermal converter for a plurality of electrothermal converters, and an opening for absorbing a pressure wave of thermal energy is provided. The effect of the present invention is effective even if the configuration is based on JP-A-59-138461, which discloses a configuration corresponding to a discharge unit. That is, according to the present invention, recording can be reliably and efficiently performed regardless of the form of the recording head.

Further, the present invention can be effectively applied to a full-line type recording head having a length corresponding to the maximum width of a recording medium on which a recording apparatus can record. Such a recording head may have a configuration that satisfies the length by a combination of a plurality of recording heads, or a configuration as one integrally formed recording head.

In addition, even in the case of the serial type as described above, a recording head fixed to the apparatus main body or an electric connection with the apparatus main body or ink from the apparatus main body by being attached to the apparatus main body. The present invention is also effective when a replaceable chip-type recording head that can be supplied or a cartridge-type recording head in which an ink tank is provided integrally with the recording head itself is used.

It is preferable to add a recording head ejection recovery unit, a preliminary auxiliary unit, and the like as the configuration of the recording apparatus of the present invention since the effects of the present invention can be further stabilized. Specifically, capping means for the recording head, cleaning means, pressurizing or suction means, an electrothermal transducer, or another heating element, or a combination thereof is used. Preheating means for performing heating by heating, preliminary ejection means for performing ejection different from recording, and the like.

The type and number of recording heads to be mounted are, for example, not only those provided for one color ink but also a plurality of inks having different recording colors and densities. A plurality may be provided. That is, for example, the printing mode of the printing apparatus is not limited to a printing mode of only a mainstream color such as black, and may be any of a printing head integrally configured or a combination of a plurality of printing heads. The present invention is also very effective for an apparatus provided with at least one of the recording modes of full-color recording or full-color recording.

In addition, in the embodiment of the present invention described above, the ink is described as a liquid. However, an ink which solidifies at room temperature or lower and which softens or liquefies at room temperature may be used. In general, the ink jet method generally controls the temperature of the ink itself within a range of 30 ° C. or more and 70 ° C. or less to control the temperature so that the viscosity of the ink is in a stable ejection range. Sometimes, the ink may be in a liquid state. In addition, in order to positively prevent temperature rise due to thermal energy by using it as energy for changing the state of the ink from a solid state to a liquid state, or to prevent evaporation of the ink, the ink is solidified in a standing state and heated. May be used. In any case, the application of heat energy causes the ink to be liquefied by the application of the heat energy according to the recording signal and the liquid ink to be ejected, or to start to solidify when reaching the recording medium. The present invention is also applicable to a case where an ink having a property of liquefying for the first time is used. In such a case, the ink is disclosed in JP-A-54-56847 or JP-A-6
As described in Japanese Patent Application Laid-Open No. 0-71260, a mode may be adopted in which the liquid sheet or the solid sheet is held as a liquid or a solid in the concave portion or through hole of the porous sheet so as to face the electrothermal converter. In the present invention, the most effective one for each of the above-mentioned inks is to execute the above-mentioned film boiling method.

Further, the form of the ink jet recording apparatus of the present invention is not limited to the one used as an image output terminal of an information processing apparatus such as a computer, a copying apparatus combined with a reader or the like, and a facsimile apparatus having a transmission / reception function. It may take a form.

[0056]

According to the first aspect of the present invention having the above-described structure,
The inkjet recording apparatus according to the aspect of the invention includes an inkjet recording element, an inkjet recording head having a sub-tank for pooling ink, an ink supply pipe for supplying ink from the sub-tank to the inkjet recording element, a main ink tank, and a main ink tank. In a recording apparatus including an ink supply unit that supplies ink from an ink tank to the sub-tank, the ink supply pipe protrudes into the sub-tank, and a meniscus forming portion is provided on a side surface of the protruding portion. In addition to being easily made, the air bubbles accumulated in the sub-tank can be easily removed by a suction operation, and the capacity of the sub-tank can be reduced, so that the printer body can be made compact.

In the ink jet recording apparatus according to the second aspect of the present invention, since the meniscus forming section is formed in a nozzle shape, the meniscus forming section in the ink supply pipe can be easily processed.

In the ink jet recording apparatus according to the third aspect of the present invention, since the meniscus forming portion is formed in a slit shape, it can be easily processed.

In the ink jet recording apparatus according to a fourth aspect of the present invention, since at least a part of the ink supply pipe is made of a porous material, the ink supply pipe can be easily formed, and the gas accumulated in the sub tank can be removed. It can be suitably removed by suction.

In the ink jet recording apparatus according to the fifth aspect of the present invention, since the porous material is a material obtained by compression-molding a fiber, the porous material portion of the ink supply pipe can be easily formed, and the ink supply pipe can be formed in the sub-tank. The accumulated gas can be reliably removed by suction.

In the ink jet recording apparatus according to the sixth aspect of the present invention, at least a part of the ink supply pipe is made of a mesh, so that the gas accumulated in the sub tank can be easily removed by suction.

In the ink jet recording apparatus according to a seventh aspect of the present invention, since the ink jet recording head has the ink jet recording element connected to the ink supply pipe, the gas accumulated in the sub tank of the recording head is suctioned. It can be easily removed.

In the ink jet recording apparatus according to the eighth aspect of the present invention, since the suction recovery unit is brought into close contact with the ink jet recording head to perform the suction recovery process, the recovery of the recording head can be easily performed.

The ink jet recording apparatus according to the ninth aspect of the present invention has an electrothermal converter for generating heat energy used by the ink jet recording head to eject ink. By discharging, high density and high definition of the recording can be achieved, and a clear recording can be obtained.

In the ink jet recording apparatus according to a tenth aspect of the present invention, since the electrothermal transducer generates electric energy that causes film boiling of the ink, the ink is ejected using the electric energy. Higher recording density and higher definition can be achieved, and clear recording can be obtained.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a configuration of an ink jet recording apparatus to which the present invention is applied.

FIG. 2 is a detailed view of a recording head of an ink jet recording apparatus to which the present invention has been applied.

FIG. 3 is a detailed view of a recording head to which the present invention is applied before the recording head is loaded on an ink jet recording apparatus.

FIG. 4 is a diagram illustrating the operation of a recording head and an ink supply system to which the present invention is applied.

FIG. 5 is an operation explanatory diagram of the recording head and the ink supply system to which the present invention is applied, following FIG. 4;

FIG. 6 is a diagram illustrating the operation of the print head and the ink supply system to which the present invention is applied, following FIG.

FIG. 7 is a diagram illustrating the operation of the recording head and the ink supply system to which the present invention is applied, following FIG.

FIG. 8 is an operation explanatory diagram following FIG. 7 of the recording head and the ink supply system to which the present invention is applied;

9 is an explanatory diagram of the operation of the recording head and the ink supply system to which the present invention of FIG. 2 is applied.

FIG. 10 is a detailed view of a recording head according to a second embodiment of the inkjet recording apparatus of the present invention.

FIG. 11 is a detailed view of a recording head according to a third embodiment of the inkjet recording apparatus of the present invention.

FIG. 12 is a detailed view of a recording head according to a fourth embodiment of the inkjet recording apparatus of the present invention.

FIG. 13 is a diagram illustrating a configuration of a conventional inkjet recording apparatus.

FIG. 14 is a diagram illustrating the operation of an ink supply system in a conventional inkjet recording apparatus.

FIG. 15 is a diagram illustrating the operation of an ink supply system in a conventional inkjet recording apparatus.

FIG. 16 is a diagram illustrating the operation of an ink supply system in a conventional inkjet recording apparatus.

FIG. 17 is an explanatory diagram of the operation of the ink supply system in the conventional ink jet recording apparatus, following FIG.

FIG. 18 is an operation explanatory diagram following FIG. 17 of the ink supply system in the conventional inkjet recording apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Main ink tank 2 Ink jet recording head 3 Sub tank 4 Tube 5A, 5B Joint part 7 Recording element 8 Ink supply pipe 8A Small hole 8B Meniscus 8C Slit 8D Porous material 8E mesh 10 Ink jet recording device 11A, 11B Chassis 12 Shaft 13 Carriage 14 Recording medium 15 Roller 16 Suction recovery unit

Claims (10)

[Claims] 1. An ink jet recording head having an ink jet recording element, a sub tank for pooling ink, an ink supply pipe for supplying ink from the sub tank to the ink jet recording element, a main ink tank, and a main ink tank An ink supply unit for supplying ink to the sub-tank from the above, wherein the ink supply pipe protrudes into the sub-tank, and a meniscus forming portion is provided on a side surface of the protruding portion. . 2. The ink jet recording apparatus according to claim 1, wherein said meniscus forming portion is formed in a nozzle shape. 3. The ink jet recording apparatus according to claim 1, wherein said meniscus forming portion is formed in a slit shape. 4. The ink jet recording apparatus according to claim 1, wherein at least a part of said ink supply pipe is made of a porous material. 5. An ink jet recording apparatus according to claim 4, wherein said porous material is a material obtained by compression-molding a fiber. 6. An ink jet recording apparatus according to claim 1, wherein at least a part of said ink supply pipe is a mesh. 7. The ink jet recording apparatus according to claim 1, wherein the ink jet recording head of the ink jet recording head is connected to the ink supply pipe. 8. The ink jet recording apparatus according to claim 1, wherein the ink jet recording head performs a suction recovery process by closely contacting a suction recovery unit. 9. The ink jet recording apparatus according to claim 1, wherein said ink jet recording head has an electrothermal converter for generating thermal energy used for discharging ink. 10. An ink jet recording apparatus according to claim 9, wherein said electrothermal converter generates electric energy for causing film boiling of the ink.