JP2004042288A - Inkjet recorder, inkjet recording method, and recording head - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inkjet recorder capable of appropriately ejecting a plurality of ink having different densities in the same hue and forming a high quality image while reducing the cost greatly. <P>SOLUTION: The recording head ejecting ink comprises a head section having a nozzle array arranged with a plurality of nozzles, and an ink tank 20 for supplying ink to the head section.The ink tank 20 has at least one kind of ink reservoirs S1 and S2 for storing ink of different densities, respectively, which are fixed to the head section removably.The recording head further comprises a means for ejecting a plurality of ink having different densities from the same nozzle array by replacing the ink tank 20 and actuating a control operation related to recording operation selectively depending on alteration of the ink reservoir. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an inkjet recording apparatus and an inkjet recording method for performing recording by discharging ink droplets on a recording medium, and more particularly to an inkjet recording apparatus, an inkjet recording method, and a recording head that perform recording using a plurality of types of colorants. .
[0002]
[Prior art]
Generally, a conventional inkjet recording apparatus performs recording by ejecting ink based on a recording data signal from a plurality of ink ejection ports provided in a recording head, and attaching ink droplets to a recording medium such as paper. For example, it is used in a recording unit such as a printer, a facsimile or a copying machine.
[0003]
As an ink ejection method applied to the ink jet recording apparatus, a heating element (also referred to as an electric heat energy conversion element) is provided in an ink flow path near an ink ejection port, and an ink is applied by applying an electric signal to the heating element. Are locally heated to generate bubbles, and a method of ejecting ink from a discharge port by a change in ink pressure due to the energy generated by the bubbles, and a method of using an electromechanical energy conversion element such as a piezoelectric element are known.
[0004]
In an ink jet recording apparatus using this type of ink ejection method, as a halftone recording method, a fixed size ink dot is recorded, and the number of recording dots per unit area is controlled to express the halftone. In order to make the dot density control method or the graininess, which is a drawback of those control methods, inconspicuous, low-density ink (hereinafter also referred to as light ink) and dark ink (hereinafter also referred to as dark ink) are used. Ink is ejected individually from two recording heads provided exclusively for ink, recording dots are formed with light ink from the bright part to the halftone part of the image, and recording dots are made with the dark ink from the halftone part to the dark part. Is known.
[0005]
According to such a multi-level recording method using a plurality of dark and light inks having different densities in the same hue, the gradation of a highlight portion is particularly improved as the number of levels increases, and the granularity of dots is increased. Is reduced, and high image quality can be obtained. This is because the low-density (light) ink can be ejected into the highlight portion to eliminate the noise of light dots.
[0006]
For this reason, most high-quality type ink jet printers adopt this dark / light recording method in most cases.
[0007]
[Problems to be solved by the invention]
However, the recording apparatus using both the dark and light inks has the following problems, and a solution is desired.
[0008]
That is, most of the images output by the printer are currently recorded using only dark ink, such as tables, graphs, and characters, and are used to form high-quality images such as photographs. The frequency at which both the dark and light inks are used is lower than when only the dark ink is used.
[0009]
Even in such an ink usage situation, current printers that require high-quality recording need to have a function that can appropriately discharge both dark and light inks. On the other hand, as described above, two types of heads, that is, a dark head and a light head, can be mounted, and this has caused a cost increase.
[0010]
In other words, in a conventional ink jet recording apparatus capable of forming an image with a small granularity using light ink, a high-priced recording head equipped with a light ink recording head with a low usage rate in addition to a recording head for dark ink is used. Had become something. For this reason, at present, the user is forced to choose between purchasing an expensive device having a function with a low usage rate or purchasing an inexpensive device without a light head.
[0011]
SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the related art, and it is possible to appropriately discharge a plurality of inks having different densities in the same hue, thereby enabling high-quality image formation and significantly reducing costs. It is an object of the present invention to provide an ink jet recording apparatus capable of reducing the amount of ink.
[0012]
[Means for Solving the Problems]
Therefore, the present invention has the following configuration.
[0013]
That is, the invention according to claim 1 is an ink jet recording apparatus that includes a recording head that discharges ink, and forms an image by discharging ink from the recording head toward a recording medium. A head unit having a nozzle array formed by arranging a plurality of nozzles, and at least one type of ink storage unit for storing and storing inks having different densities for each density can be detachably attached to the head unit. An ink tank that stores a plurality of types of inks having different densities is mounted on the head unit, so that a plurality of types of inks having different densities can be ejected from the same nozzle row. Is what you do.
[0014]
According to a second aspect of the present invention, there is provided an ink jet recording apparatus comprising a recording head for discharging ink, and forming an image by discharging ink from the recording head toward a recording medium. And a head unit having a nozzle array formed by arranging the nozzles, and at least one type of ink storage unit configured to store and store inks having different densities for each of the densities. A plurality of inks having different densities are stored in the head unit so that a plurality of inks having different densities can be ejected from the same nozzle row. Selecting means for selectively executing a control operation related to a recording operation corresponding to the ink tank mounted on the printer. .
[0015]
According to a third aspect of the present invention, in the second aspect of the present invention, the selection unit detects a type of the ink tank mounted on the head unit, and the detection unit detects the type of the ink tank detected by the detection unit. Switching means for switching a control operation related to the recording operation according to a type.
[0016]
According to a fourth aspect of the present invention, in the second aspect of the present invention, the selection means selectively executes a control operation related to a recording operation by a selection signal input by an input operation means. It is.
[0017]
According to a fifth aspect of the present invention, in the first aspect of the present invention, the ink tank is formed in a plurality of ink storage sections in a single housing detachably provided to the recording head. It is characterized by becoming.
[0018]
According to a sixth aspect of the present invention, in the first aspect of the invention, the ink tank is provided detachably and independently of the recording head, and has at least one of the same hue and a different density. It is characterized by storing more than one kind of ink.
[0019]
According to a seventh aspect of the present invention, in the first aspect of the present invention, the recording head includes a head portion formed with a nozzle row having a plurality of nozzles for ejecting ink, and the head portion is attached and detached. And a tank holder for holding the tank as possible.
[0020]
According to an eighth aspect of the present invention, in the first aspect of the present invention, the recording head generates film boiling in the ink by thermal energy, and discharges the ink from the nozzle by the energy. Things.
[0021]
According to a ninth aspect of the present invention, there is provided an ink jet recording method comprising: a recording head for discharging ink; and forming an image by discharging ink from the recording head toward a recording medium. And a head unit having a nozzle array formed by arranging the nozzles, and at least one type of ink storage unit configured to store and store inks having different densities for each of the densities. A plurality of inks having different densities are stored in the head unit so that a plurality of inks having different densities can be ejected from the same nozzle row. Characterized by a step of selectively executing a control operation related to a recording operation corresponding to the ink tank attached to the printer.
[0022]
A recording head according to the invention according to claim 10, wherein a head portion having a nozzle array formed by arranging a plurality of nozzles, and at least one type of ink storage for storing ink having different densities for each density. An ink tank that can be detachably attached to the head unit, and an ink tank storing a plurality of types of inks having different densities is attached to the head unit so that a plurality of types of inks having different densities are the same. The nozzles can be ejected.
[0023]
[Action]
In the present invention having the above configuration, the ink tank includes at least one type of ink storage unit that stores one or more types of inks having different densities for each density. Since the storage section can be detachably arranged along the arrangement direction of the nozzles of the head section, it is possible to discharge a plurality of inks having different densities from the same head section by replacing the ink tank. Can be. For this reason, for example, according to the type of image to be printed, high-quality printing using both dark and light inks and printing operation of characters and the like using only dark inks are performed without changing the head part without changing the ink tank. This can be done by exchanging only one.
[0024]
Further, when the ink tanks are replaced and inks having different densities are used, more appropriate printing can be performed by changing the control operation related to the printing operation according to the change of the type of the ink tank. In this case, if the type of the ink tank mounted on the head portion is automatically detected and the detection is automatically performed according to the detection result, the handling becomes extremely easy.
[0025]
Further, when changing from a printing operation using both dark and light inks to a printing operation using only dark ink, dark ink can be supplied to the nozzles used for discharging the light ink, and The number of nozzles used for discharging dark ink is increased as compared with the case where both light inks are used. For this reason, the printing operation speed can be improved, and high-quality printing using the multi-pass printing method can be performed at the same printing speed.
[0026]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[0027]
FIG. 1 is a perspective view showing a main part configuration of an ink jet recording apparatus according to the first embodiment of the present invention. FIG. 2 is a perspective view of the appearance of a recording head used in the ink jet recording apparatus shown in FIG.
[0028]
As shown in FIG. 1, in the ink jet recording apparatus according to the first embodiment, a carriage 3 is moved along a main scanning direction (X direction) which is an axial direction thereof by a guide shaft 2 supported at both ends by a main body 1. Are movably supported, and two recording heads 10 and 20 are detachably mounted on the carriage 3. The carriage 3 is fixed to a driving belt that is turned by the driving force of a carriage motor, and reciprocates with the driving belt 4 in the main scanning direction (X direction).
[0029]
A recording medium, such as recording paper or a plastic thin plate, on which an image is to be recorded is fed from a paper supply unit (not shown) to a recording area on a platen arranged opposite to the recording heads 10 and 20 by a paper supply roller. Then, the sheet is conveyed in the sub-scanning direction (arrow Y direction) orthogonal to the main scanning direction by cooperation of the conveying roller and the sheet discharging roller.
The operation of transporting the recording medium and the movement of the carriage are alternately and repeatedly performed, while the recording head is driven in synchronization with the movement of the carriage, and an ink ejection operation according to the recording data is performed. A predetermined image is formed.
[0030]
In addition, a recovery unit having a cap portion 7 is provided at a home position of the carriage 3 which is located at a position other than the recording area. In this ink jet recording apparatus, when the recording operation is not performed, the carriage 3 is moved to the home position, and the cap of the cap section 7 covers the corresponding ink discharge ports of the recording heads 10 and 20 to prevent evaporation of the ink solvent. Accordingly, clogging of the ink ejection port due to thickening of the ink or adhesion of foreign matter such as dust due to this is prevented.
[0031]
Further, the cap portion 7 is used for the purpose of eliminating ejection failure or clogging of an ink ejection port having a low ejection frequency by ejecting the ink from the recording heads 10 and 20 thereto. It is also used for removing a thickened ink by sucking ink from the ink discharge port by operating a pump (not shown) with the ink discharge port capped. In addition, by disposing a wiping blade adjacent to the cap portion 7, it is possible to clean the discharge port forming surface.
[0032]
By the way, of the two recording heads 10 and 11 mounted on the carriage, one of the recording heads 10 is a recording head for discharging K (black) ink, and the other recording head is for recording dark ink. The recording head is capable of discharging both light and dark inks and discharging only dark ink. Here, the recording head ejects K (black) ink, and includes deep C (dark cyan), dark M (dark magenta), dark Y (dark yellow), light C (light cyan), and light C (light cyan). The ink of six colors such as M (light magenta) and Y (light yellow) is ejected.
[0033]
Each of the recording heads 10 and 20 includes head units 11 and 21 for discharging ink, and ink storage units 14 and 24 for supplying ink to the head units 11 and 21 (see FIG. 2).
[0034]
FIGS. 2 to 4 are views showing the structure of the recording head 20 used for discharging both dark and light inks applied in the first embodiment.
[0035]
In the recording head 20, the head section 21 includes an ejection section 22 and a tank holder 23.
[0036]
FIG. 4 is a longitudinal sectional view schematically showing the structure of the ejection section 22 of the head section 21. The discharge section 22 has a top plate 22A in which an ink introduction path 22A, an ink liquid chamber 22A2, an ink flow channel 22A3, an ink discharge port 22A3, and the like are formed, and a wiring board 22B on both sides of the top plate 22A. Are bonded and electrically connected to the substrate 22C of the resistive heating element. The wiring substrate 22B transmits the electric signal transmitted to the recording apparatus main body 1 to the substrate 22C on which the resistance heating element is mounted.
[0037]
Therefore, the ink flows from the ink tank 24 through the ink introduction path 22A1, into the ink liquid chamber 22A2 formed by the top plate 22A and the substrate 22C having the resistive heating element, and further from there, the resistive heating element The ink is guided to a certain ink flow channel 22A3 and reaches the ink ejection port 22A4. The ink guided to the ink flow channel 22A3 causes film boiling due to thermal energy of a resistive heating element driven according to print data input to the printing apparatus main body 1, and is discharged from the ink discharge port 22A4.
The ink liquid chamber 22A2 is formed of a top plate 22A and a substrate 22C having a resistive heating element, and is provided for each hue when the hue is different, and for each density when the density is different.
[0038]
The space between the top plate 22A and the substrate 22C is sealed with a sealant to prevent ink leakage. This sealant is also used for a TAB connection between the substrate 22C having the resistive heating element and the wiring substrate 22B, and prevents and protects the adhesion of ink.
The top plate 22A is integrally formed, and the ink discharge port 22A, the ink flow channel 22A3, the ink liquid chamber 22A2, and the ink introduction path 22A1 are processed by molding or laser processing. It is particularly required that the channel groove 22A3 be processed with high precision. It is necessary to select a material that has good moldability and is not easily eroded by the ink for the integrally molded top plate 22A. As a specific material, for example, polysulfone is used.
[0039]
The substrate 22C having a resistive heating element is for recording by causing film boiling in the ink by thermal energy, and includes a plurality of resistive overheating elements arranged in a plurality of rows on a Si (silicon) substrate. Electrical wiring such as AI for supplying electric power is formed by a film forming technique, and a film of Ta or the like is formed on the surface of the substrate which is in direct contact with the ink to protect the substrate. Further, the substrate 22C incorporates a shift register and a driving transistor in order to reduce the number of TAB pads. Then, the substrate 22C is fixed to the top plate 22A by the mechanical biasing force of the elastic member 22D.
[0040]
FIG. 5 is a perspective view showing an external configuration of the tank holder 23.
[0041]
As shown, the tank holder 23 forms an ink path for guiding the ink from the ink tank 24 to the ink introduction path 22A1 of the head unit 21 and functions as a holding member for holding the ink tank 24 and the head unit 21. I do. That is, in the tank holder 23 for both the dark and light inks, six cylindrical fitting projections 23a are formed on the inner surface of the bottom to form a flat ellipse, and these are formed into an oval formed on the bottom of the ink tank 24. Can be fitted to and removed from the ink ejection port 24a1.
An ink inlet 23b is formed inside the fitting protrusion 23a, and a filter 23c for preventing dust and bubbles from entering is welded to the ink inlet 23b. Further, a packing is interposed at the connecting portion between the tank holder 23 and the discharge section, thereby completely preventing ink leakage.
[0042]
The ink tank 24 is configured as shown in FIGS.
[0043]
In each of the drawings, an ink tank 24 includes a tank body 24a formed of a hollow rectangular parallelepiped housing having an upper opening, an ink absorber 24b inserted therein, and a lid 24c for closing the upper opening of the tank body 24a. Is provided. The tank main body 24a has an inner space defined by a plurality of partition plates 24a1 to define a plurality of spaces for liquid storage. In this case, three sets of large and small spaces S1 and S2 for storing liquid are arranged in parallel. And a total of six ink storage spaces are formed.
[0044]
Of these six liquid storage spaces S1 and S2, the space S1 having a large capacity is suitable for use as a frequently used space for storing dark ink (space for storing dark M, dark C, and dark Y ink). The small-capacity space S2 is suitable for use as a light ink storage space (light M, light C, light Y ink storage space) that is used less frequently. However, the three spaces S2 are used as a space for storing dark ink, and a space in which three colors of dark ink are stored in the entire ink tank is also prepared.
On the bottom surface of the tank body 24a, six ink supply ports 24a2 and 24a4 communicating with the respective spaces are formed to protrude.
The ink storage spaces S1 and S2 are filled with an ink absorber 24b capable of holding ink by capillary force. The ink absorber 24b includes first ink absorbers 24b1 and 24b3 that absorb and hold a required storage amount of ink, and a second ink absorber that is disposed below the first ink absorbers 24b1 and 24b3. The body 24b2, 24b4. The second absorbers 24b2 and 24b4 generate a stronger capillary force than the first absorbers 24b2 and 24b4, and the ink absorbed by the first absorbers 24b1 and 24b3 is transferred to the bottom of the tank body 24a. And a function of guiding the ink to the ink supply ports 24a2 and 24a4.
[0045]
Further, the lid 24c is adhesively fixed to the upper end of the tank main body 24a filled with the ink absorbers 24b1 and 24b3 so as to close the upper opening of the tank main body. The inks are controlled in a liquid-tight manner, so that color mixing of each ink can be completely prevented. The lid 24c has air communication ports 24c1 and 24c2 communicating with the liquid storage spaces S1 and S2, respectively.
[0046]
Note that the recording head 10 for dark ink (see FIG. 7) has substantially the same configuration as the recording head 20 for both dark and light inks. The first embodiment differs from the first embodiment in that the space is divided into three equal parts, and the first ink absorber 14b1 and the second ink absorber 14b2.14b4 are provided in substantially the entire internal space. . However, like the ink tank 20, six ink supply ports (not shown) are formed on the lower surface of the ink tank. This is because the structure is changed as little as possible to be mounted on the dark / light holder. In FIG. 7, the same or corresponding parts as those shown in FIG. 6 are denoted by the same reference numerals.
[0047]
FIG. 8 is a block diagram showing a schematic configuration of a control system according to the first embodiment.
[0048]
In the figure, reference numeral 101 denotes a CPU as a control means for controlling the operation of each unit of the printing apparatus in this embodiment, and 102 stores a control program for controlling the driving of the printing head in accordance with each of the printing methods set in advance, which will be described later. ROM 103 is a RAM as a recording area for temporarily storing various data.
[0049]
The CPU 101 detects an input operation unit 105 having various setting switches including a power switch and the like, and detects the type of ink tank of a recording head mounted on the carriage 3 and outputs an output corresponding to the detected result. The tank identification sensor 104 for transmitting the data is connected to the storage unit. The tank identification sensor 104 and the CPU 101 as a switching unit constitute a selection unit. The identification of the ink tank is carried out by reading the content of a detection object (not shown) provided on the side face of the ink tank by magnetic, optical, or mechanical detection means provided on the carriage 3, and outputting the output to the CPU 101. By doing so.
[0050]
Further, the CPU 101 is connected to a paper feed motor 107 for driving the above-mentioned paper feed roller, a carriage motor 109, and motor drive circuits 106, 108 and 110 for driving a pump drive motor 111 of a preliminary ejection mechanism and the like. Are controlled by the CPU 101.
[0051]
In the ink jet recording apparatus having the above configuration, the change between the normal color image recording using only the dark ink and the high image quality recording using both the dark and light inks can be easily performed simply by replacing the ink tank. be able to.
[0052]
The replacement of each ink tank 24 can be performed by inserting the tank main body 24a into the tank holder 23 that guides the outer surface thereof along the inner surface. That is, when the ink tank 24 is inserted into the tank holder 23 when the ink tank is mounted, the ink supply ports 24a2 and 24a4 formed at the bottom of the ink tank 24 are fitted to the fitting projections 23a2 and 23a4 of the tank holder 23. The second ink absorbers 24b2 and 24b4 exposed from the ink supply ports 24a2 and 24a4 are fitted to the ink introduction ports 23b2 and 23b4 formed in the fitting projections 23a2 and 23a4, respectively. The ink that is in contact with and is guided by the second ink absorbers 24b2 and 24b4 is supplied into the head unit 20 via the filter 23c.
[0053]
In this manner, when the ink tank is mounted, the tank identification sensor 104 automatically reads the detection target of the ink tank mounted on the recording head 20 and inputs the data to the CPU 101. Based on the input data, it is determined whether the type of the ink tank has been changed or only the same type of ink tank has been replaced with a new one. Based on the determination result, the control of the recovery operation and the control of the recording operation are performed. Perform
[0054]
That is, when it is determined that the type of the ink storage unit has been changed, the ink suction recovery amount is increased, and when the ink tank 24 (ink tank for both dark and light ink) is installed, the halftone expression is used. A recording control method of recording using both dark and light inks is adopted. When the ink storage unit 24 (only dark ink) is mounted, the halftone expression is recorded by the dot density control method or the dot diameter control method. Make any changes. Therefore, according to this embodiment, it is possible to automatically and reliably execute an appropriate recording operation according to the type of the attached ink tank.
[0055]
Usually, the recording heads for both dark and light inks have the same number of dark ink ejection nozzles and light ink ejection nozzles. Can also be used, so that the number of usable nozzles is doubled. Therefore, it is possible to increase the printing speed by about twice or to print at twice the number of passes by using a multi-pass method or the like even at the same printing speed, thereby improving image quality. be able to.
In the recording head 10 for dark ink, the mounting of the ink tank 14 on the head section 11 can be performed in the same manner as the recording head 20 for both dark and light ink.
By the way, when ink jet recording is performed using both dark and light inks, the deviation between the landing positions of the dark ink dots and the light ink dots has a great effect on the image quality, causing uneven density and streaks in the image. Sometimes For this reason, in the conventional recording apparatus in which the dark ink and the light ink are stored in separate recording heads, there is a problem that the above-mentioned inconvenience is likely to occur.
[0056]
However, in this embodiment, the ink ejection ports corresponding to the inks having different densities of dark and light are arranged in a line in the single head unit 21, and the positional relationship of the ink ejection ports is fixed regardless of the exchange of the ink used. , The displacement of the landing positions of the ejected ink dots can be reduced, and the occurrence of unevenness and streaks due to the landing positions can be suppressed. This is similarly effective when the light ink is replaced with the dark ink and recording is performed using only the dark ink.
[0057]
Further, in the ink tank 14 of the recording head 10 for dark ink, a partition plate that controls the space S1 for storing dark ink and the space S2 for storing light ink like the ink tank 24 is not formed. The dark ink is also stored in a space corresponding to the ink space S2, and six ink supply ports are formed on the bottom surface thereof in the same manner as the ink tank 14 for both dark and light inks. This is because the recording head 10 for dark ink and the recording head 20 for both dark and light inks have a common head portion, thereby reducing the manufacturing cost of both recording heads 10 and 20. Has become.
[0058]
FIG. 9 to FIG. 12 are views showing a recording head and an ink storage unit according to the second embodiment of the present invention. The recording head in this embodiment is one in which inks having different hues are stored in separate and independent ink tanks. As shown in FIGS. 9 and 10, the ink tanks include three types of dark ink tanks (dark C ink tank 34a, dark M ink tank 34b, and dark Y ink tank 34c) storing only dark ink. As shown in FIGS. 11 and 12, a total of six ink tanks of three types (dark C ink tank 34d, light M ink tank 34e, light Y ink tank 34f) storing dark ink and light ink of the same hue are used. Each of the ink tanks is provided so as to be individually detachable from the head portion 24a. The head portion 24a has six fitting protrusions and an ink inlet (both not shown) at the bottom, similarly to the head portion 24a shown in the first embodiment. Two ink discharge ports are formed at the bottom of each ink tank (not shown), and the dark ink or the dark and light inks supplied from the same ink tank are discharged to the same row of ink discharge ports. Is supplied.
[0059]
That is, when the dark ink tanks 34a to 34c are mounted, inks of the same hue and density are supplied to the entire ink ejection ports in the same row, and the ink tanks 34d to 34f for both dark and light inks are mounted. In such a case, dark ink is supplied to half of the nozzles in the same nozzle row, and light ink is supplied to the remaining half of the nozzles.
Each ink tank is provided with a detection target that can be read by magnetic, optical, or mechanical detection means provided in a recording apparatus main body or the like. Can be identified.
[0060]
Other configurations including the tank holder and the like are the same as those in the first embodiment.
[0061]
As described above, according to the second embodiment, the ink tanks 34d to 34f for both dark and light inks and the ink tanks 34a to 34c for dark ink can be appropriately replaced according to the image to be formed. As a result, it is possible to perform high-quality printing using both dark and light inks, and to improve the speed of a printing operation performed using only dark ink, similar to the first embodiment. In addition, since each ink tank is independent, even if one type of ink is completely consumed, only the ink tank of that part needs to be replaced, keeping the total running cost low. There is also the advantage of being able to do it.
[0062]
In the above-described embodiment, two types of density are used for the ink of the same hue, but three or more types of density can be applied. However, in that case, it is necessary to change the number of ink supply ports of the ink tank and the number of ink introduction ports of the head unit according to the number of ink concentrations to be applied.
[0063]
Further, in each of the above embodiments, the recording control method is automatically selected according to the type of the attached ink tank. However, the user may manually select the recording control method as described above. In such a case, a sensor, an electric circuit, a program, and the like for recognizing the type of the ink storage section are not required, so that an inexpensive inkjet recording apparatus can be provided.
[0064]
(Other)
In addition, the present invention includes a means (for example, an electrothermal converter or a laser beam) for generating thermal energy as energy used for causing ink to be ejected, particularly in an ink jet recording system. The present invention brings about an excellent effect in a recording head and a recording apparatus of a type that causes a change in the state. This is because according to such a method, it is possible to achieve higher density and higher definition of recording.
[0065]
Regarding the typical configuration and principle, it is preferable to use the basic principle disclosed in, for example, US Pat. Nos. 4,723,129 and 4,740,796. 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, and This is effective because film boiling occurs on the heat-acting surface of the liquid, and as a result, air bubbles in the liquid (ink) corresponding to this drive signal one-to-one can be formed. 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 in 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. Further, if the conditions described in US Pat. No. 4,313,124 of the invention relating to the temperature rise rate of the heat acting surface are adopted, more excellent recording can be performed.
[0066]
As the configuration of the recording head, in addition to the combination configuration (straight liquid flow path or right-angle liquid flow path) of the discharge port, liquid path, and electrothermal converter as disclosed in the above-mentioned specifications, 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 is bent, is also included in the present invention. In addition, Japanese Unexamined Patent Application Publication No. 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 aperture 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 performed reliably and efficiently regardless of the form of the recording head.
[0067]
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 combining a plurality of recording heads, or a configuration as a single recording head that is integrally formed.
[0068]
In addition, even with the serial type printer as in the above example, the recording head fixed to the main unit or attached to the main unit enables electrical connection with the main unit and supply of ink from the main unit. The present invention is also effective when a replaceable chip-type recording head or a cartridge-type recording head in which an ink tank is provided integrally with the recording head itself is used.
[0069]
Further, it is preferable to add ejection recovery means for the recording head, preliminary auxiliary means, 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, heating is performed on the recording head by using capping means, cleaning means, pressurizing or suction means, an electrothermal transducer or another heating element or a combination thereof. Pre-heating means for performing the pre-heating and pre-discharging means for performing the discharging other than the recording can be used.
[0070]
Regarding the type or number of print heads to be mounted, for example, in addition to one provided for single color ink, a plurality of print heads are provided corresponding to a plurality of inks having different print colors and densities. May be used. That is, for example, the printing mode of the printing apparatus is not limited to the printing mode of only the mainstream color such as black, but may be any of integrally forming the printing head 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 by color mixture.
[0071]
In addition, in the embodiment of the present invention described above, the ink is described as a liquid, but an ink that solidifies at room temperature or below, and that softens or liquefies at room temperature may be used. Alternatively, in the ink jet system, the temperature of the ink itself is controlled within the range of 30 ° C. or more and 70 ° C. or less to control the temperature so that the viscosity of the ink is in the stable ejection range. May be in a liquid state. In addition, in order to positively prevent the 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 the ink from evaporating, 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 held in a state of being held as a liquid or solid substance in the concave portion or through hole of the porous sheet as described in JP-A-54-56847 or JP-A-60-71260. Alternatively, it may be configured 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.
[0072]
In addition, as the form of the ink jet recording apparatus of the present invention, in addition to a form used as an image output terminal of an information processing device such as a computer, a form of a copying apparatus combined with a reader or the like, and a facsimile apparatus having a transmission / reception function are adopted. Or the like.
[0073]
【The invention's effect】
As described above, according to the present invention, by changing the ink tank, inks having different densities can be recorded from the same discharge port. Printing can be performed easily, and ink dots can be ejected in a fixed positional relationship regardless of the change of the ink tank, greatly reducing density unevenness and streaking. It becomes.
[0074]
In addition, if the type of the ink tank attached to the head unit is automatically identified and the recording operation is controlled according to the result, an appropriate recording operation can be reliably performed.
[Brief description of the drawings]
FIG. 1 is a perspective view schematically showing a state in which a recording head according to a first embodiment of the present invention is mounted on a recording apparatus.
FIG. 2 is a perspective view illustrating an appearance of a recording head according to the first embodiment of the present invention.
FIG. 3 is an external perspective view illustrating a state in which an ink tank is taken out of a head unit in the recording head illustrated in FIG. 2;
4 is a semi-longitudinal sectional view showing a structure of a head portion of the recording head shown in FIG.
FIG. 5 is a perspective view of the holder shown in FIG.
FIG. 6 is an exploded perspective view of the ink tank for both dark and light inks shown in FIG. 4 and the like.
FIG. 7 is an exploded perspective view of the ink tank for dark ink shown in FIG. 4 and the like.
FIG. 8 is a block diagram illustrating a configuration of a control system according to the first embodiment of the present invention.
FIG. 9 is a plan view showing a recording head according to a second embodiment of the present invention, showing a state where an ink tank for dark ink is mounted.
FIG. 10 is a side view of the one shown in FIG. 9;
FIG. 11 is a plan view showing a recording head according to a second embodiment of the present invention, showing a state where an ink tank for dark and light ink is mounted.
FIG. 12 is a side view of what is shown in FIG.
[Explanation of symbols]
1 Recording device body
3 carriage
10 Recording head
11 Head
14 Ink tank
14b1 First ink absorber
14b2, 14b4 Second ink absorber
20 Recording head
21 Head
22 Discharge section
22A Top plate
22A1 Ink introduction path
22A2 Ink liquid chamber
22A3 Ink channel groove
22A4 ink ejection port
22B Wiring board
22C substrate
23 Tank holder
23a2, 23a4 fitting projection
23b2, 23b4 Ink ejection port
24 Ink tank
24a tank body
24a2, 24a4 Ink supply port
24b1, 24b3 First ink absorber
24b2, 24b4 Second ink absorber
24c lid
34a-34f Ink tank
S1, S2 Ink storage space (ink storage section)
101 CPU (switching means)
104 tank identification sensor

Claims (10)

An ink jet recording apparatus comprising a recording head for discharging ink, and forming an image by discharging ink from the recording head toward a recording medium.
The recording head includes:
A head section having a nozzle row formed by arranging a plurality of nozzles,
An ink tank that can be detachably attached to the head unit at least one type of ink storage unit that stores ink having different densities for each density.
An ink jet recording apparatus wherein a plurality of types of inks having different densities can be ejected from the same nozzle row by mounting an ink tank storing a plurality of types of inks having different densities on the head portion. An ink jet recording apparatus comprising a recording head for discharging ink, and forming an image by discharging ink from the recording head toward a recording medium.
The recording head includes:
A head section having a nozzle row formed by arranging a plurality of nozzles,
An ink tank that can be detachably attached to the head unit at least one type of ink storage unit that stores ink having different densities for each density.
By mounting an ink tank storing a plurality of types of inks having different densities on the head unit, it is possible to discharge a plurality of types of inks having different densities from the same nozzle row,
An ink jet printing apparatus, further comprising a selection unit for selectively executing a control operation related to a printing operation corresponding to an ink tank mounted on the nozzle unit. The selection unit includes a detection unit that detects a type of the ink tank mounted on the head unit, and a switching unit that switches a control operation related to the recording operation according to the type of the ink tank detected by the detection unit. The inkjet recording apparatus according to claim 2, comprising: 3. The ink jet recording apparatus according to claim 2, wherein the selection unit selectively executes a control operation related to a recording operation in accordance with a selection signal input by an input operation unit. 5. The ink jet recording apparatus according to claim 1, wherein the ink tank is formed so as to be divided into a plurality of ink storage sections in a single housing detachably provided to the recording head. 6. 5. The ink tank according to claim 1, wherein the ink tank is detachably provided independently of the recording head, and stores at least one or more inks having the same hue and different densities. Inkjet recording device. 7. The recording head according to claim 1, wherein the recording head includes a head unit that forms a nozzle row having a plurality of nozzles that eject ink, and a tank holder that detachably holds the head unit. Or an ink jet recording apparatus as described above. The ink jet recording apparatus according to any one of claims 1 to 7, wherein the recording head generates film boiling in the ink by thermal energy, and discharges the ink from the nozzle by the energy. An ink jet recording method comprising a recording head for discharging ink, and forming an image by discharging ink from the recording head toward a recording medium.
The recording head includes:
A head section having a nozzle row formed by arranging a plurality of nozzles,
An ink tank that can be detachably attached to the head unit at least one type of ink storage unit that stores ink having different densities for each density.
By mounting an ink tank storing a plurality of types of inks having different densities on the head unit, it is possible to discharge a plurality of types of inks having different densities from the same nozzle row,
An ink jet recording method, comprising a step of selectively executing a control operation related to a recording operation corresponding to an ink tank mounted on the nozzle portion. A head section having a nozzle row formed by arranging a plurality of nozzles,
An ink tank that can be detachably attached to the head unit at least one type of ink storage unit that stores ink having different densities for each density.
A recording head, wherein a plurality of types of inks having different densities can be ejected from the same nozzle row by mounting an ink tank storing a plurality of types of inks having different densities on the head unit.

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