JPH0624002A - Ink jet recording device and ink cassette - Google Patents

Abstract

PURPOSE:To provide an ink jet recording device eliminating an excessive part of space by making a plurality of ink jet recording heads small and also provide an ink cassette not transmitting the vibration to all over a nozzle section by absorbing the vibration so as to eliminate any inconvenience caused by the vibration generated at the time of confirming the nozzles of the ink cassette not to affect other sections. CONSTITUTION:An ink jet recording device is provided with two units of recording means comprising a plurality of ink jet openings, liquid passages, energy generating means and driving means disposed symmetrically on both faces of a support base, and an ink cassette is of a structure of a liquid chamber forming an ink storage including ink feeding passages to the nozzle section 1a and a buffer chamber 4b sealing liquid bubbles generated by the power applied periodically to heater boards, which are separated by a filter 88 protecting the liquid chamber 4a from liquid bubbles beyond the given size passing through.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet recording apparatus, and more particularly to an ink jet recording apparatus which can obtain stable recording for a long period of time, and which has an ink tank and an ink ejecting section and is provided between the ink ejecting section and the ink tank. The present invention relates to an ink cassette having an ink storage unit.

[0002]

2. Description of the Related Art A recording head applied to an ink jet recording apparatus generally has a fine liquid ejection port (orifice),
The liquid flow path and an energy acting portion provided in a part of the liquid flow passage, and an energy generating means for generating droplet forming energy to act on the liquid in the acting portion.

As such an energy generating means, an electromechanical converter such as a piezo element is used, electromagnetic waves such as a laser are radiated and absorbed by the liquid in the liquid path to generate heat, and the action of the heat is generated. The liquid is heated by an electric heat converter such as a heat generating element having a heat generating resistor, or an energy generating means for ejecting and flying droplets.
There is a device using an energy generating means for ejecting liquid. Among them, a recording head used in an inkjet recording apparatus that ejects liquid by thermal energy can have high-density arrangement of ink ejection ports for ejecting recording ink to form flying droplets. It is possible to record high resolution. further,
Among them, the recording head using the electrothermal converter as the heat energy generating means can be easily made compact as a recording head as a whole, and the IC technology has been remarkably improved in the recent technological progress in the semiconductor field. The advantages of micro processing technology and micro processing technology can be fully utilized, and it is easy to make long and planar (two-dimensional). It is possible to provide an inkjet recording head that is easy to produce and is inexpensive to manufacture, and an apparatus including the head.

An ink jet recording head manufactured through a semiconductor manufacturing process using an electrothermal converter as an energy generating means is generally provided with a liquid path corresponding to each ejection port. An electrothermal converter is provided for each of the liquid paths to apply thermal energy to the ink filling the liquid path and eject the ink from the corresponding ejection port to form flying droplets. Ink is supplied to these liquid passages from a common liquid chamber that communicates with each liquid passage.

FIG. 6 shows an example of such an ink jet recording head. An electrothermal converter 103 and an electrode 104 formed on a substrate 102 through a semiconductor manufacturing process such as etching, vapor deposition and sputtering. , The liquid path wall 105, the top plate 106, and the like. Here, the recording ink 112 is supplied from a liquid storage chamber (not shown) into the common liquid chamber 108 of the recording head 101 via the ink supply pipe 107. Reference numeral 109 in the drawing denotes an ink supply pipe connector. The ink 112 supplied into the common liquid chamber 108 is supplied into the liquid passage 110 by a so-called capillary phenomenon, and is stably held by forming a meniscus at the ejection port at the tip of the liquid passage.

Then, by selectively energizing the electrothermal converter 103, the ink on the electrothermal converter 103 is rapidly heated, and bubbles are generated in the liquid path, causing the bubbles to expand or expand. Ink is ejected from the ejection port 111 due to contraction to form flying droplets. With the above-described configuration, 128 ejection ports or 256 ejection ports are formed in a high-density ejection port array with a ejection port density of 16 nozzles / mm. It is possible to form a multi-nozzle inkjet recording head having outlets, and further, ejection ports arranged over the entire recording width.

Furthermore, various full-color printers have been proposed which are composed of a unit in which a plurality of such multi-nozzle ink jet recording heads are arranged. This is a recording sheet 1 having a width L1 as shown in FIG.
The head carriage 200 mounted with the plurality of recording heads 101 is serially moved in the direction perpendicular to the transport direction P with respect to 00. That is, by moving the head carriage 200 in the direction of the arrow S, recording is performed on the belt-shaped area a indicated by the diagonal line of the length L2 on the recording sheet 100, and then the recording head 101 ejects. The recording sheet 100 is fed in the P direction by an amount corresponding to the exit row length, and recording is performed in the next recording area b. Thus, in the following, color image recording is performed on the entire surface of the recording sheet 100 by the same procedure.

Further, recently, in order to further improve the quality of the output image by the ink jet recording method, a method of improving the gradation and graininess by using a light ink and a dark ink for the same color has been proposed. In this case, considering the formation of a full-color image, a maximum of 8 heads are required.

FIG. 13 is a perspective view of a conventional example of an ink cassette, FIG. 14 is a perspective view of a main part of the head chip 46 shown in FIG. 13, and FIG. 15 is an explanatory view of the head chip 46 shown in FIG.

The conventional ink cassette has a nozzle portion 41.
And a head structure including a head chip 46 and an ink tank 47. The nozzle portion 41 has a plurality of nozzles and a heater board 42 for bubbling ink from the nozzles. The head chip 46 is the ink supply pipe 45.
And a liquid chamber 44. Ink is sent from the ink tank 47, through the outflow port 47a, through the ink supply pipe 45 to the head chip 46, and is temporarily stored in the liquid chamber 44, and the liquid chamber 44 is filled with ink. When ink is further ejected, the heater board 42 is energized, the ink is heated in the nozzle to foam, and the foam causes the ink to be pushed out to the tip of the nozzle and then ejected. The replenishment after the ink is ejected is performed by capillary action of the nozzle and, in some cases, gravity.

[0011]

However, in the conventional ink jet recording apparatus as described above, a space for moving the carriage 200 on both sides of the maximum recording sheet width L1 used as shown in FIG. L3 is required respectively. It should be noted that such a space L3 is used as a place for performing a recovery operation and a cleaning operation of the inkjet recording head necessary for performing normal recording, but it is rare to perform this on both sides of the recording sheet width. In such a case, the space L3 on one side becomes a dead space.
Particularly, in the method using the light and dark inks described above, a dead space corresponding to the width of the carriage in which the eight recording heads are arranged is generated at the maximum. Incidentally, in the general case, the distance between adjacent recording heads is about 20 mm, so that a dead space of 160 mm to 200 mm is created as a whole, which is a great obstacle to downsizing of the apparatus.

Further, conventionally, in the ink jet recording type head 101 of this type, air cooling temperature control was mainly performed by a fan in order to keep the diameter of the ejected ink droplets constant, but the cooling means therefor is Since the heat is used to drive the head itself, the size is increased. In particular, in the case of the multi-valued light and shade, since the temperature adjusting means is prepared for each head, there are disadvantageous conditions not only in the space but also in cost and noise.

A first object of the present invention is to focus on the above-mentioned conventional problems, and in order to solve the problems, a unit composed of a plurality of recording heads is miniaturized, so that it is compact and does not waste space. An object is to provide an inkjet recording device.

Further, in the above-described conventional ink cassette, the vibration when the ink is foamed for ejection is transmitted to the liquid chamber, and the ink in the other nozzles in the vicinity is vibrated to make the foaming unstable and eject the ink. There is a drawback in that the amount of ink is not constant, the landing point of the ink deviates, white streaks, black streaks, and other printing defects occur.

Therefore, a second object of the present invention is to provide an ink cassette having a buffer that absorbs vibrations generated during foaming.

[0016]

In order to achieve the above-mentioned first object, an ink jet recording apparatus of the present invention is provided with a plurality of ink ejection openings and an array of liquid paths corresponding to the plurality of ink ejection openings, and Energy generating means disposed in each of the liquid paths for ejecting ink from the ink ejection port;
Two sets of recording means having means for driving the energy generating means are provided with ink jet recording heads symmetrically arranged on both sides of the supporting substrate.

In addition to the above-mentioned means, the above-mentioned ink jet recording apparatus of the present invention further comprises an electrothermal converter for generating heat energy for causing film boiling in the ink, as an energy generating means for ejecting the ink. The one having the two sets of recording means whose temperature and humidity are controlled by a common temperature and humidity adjusting means, and the two sets of recording means,
It also includes those that eject different color tones or different types of colors.

In order to achieve the second object, the ink cassette of the present invention has a filter which is provided in the ink storage section and prevents passage of liquid bubbles exceeding a predetermined size. Further, an electric heater is provided in an area of the ink storage section, which is separated by a filter and does not include the ejection section.

In addition to the above-mentioned features, the ink cassette of the present invention is an electrothermal converter in which the discharge energy of the ink discharge energy generating means generates heat energy, and the entire width of the recording area of the recording medium. Those including a full-line type inkjet recording head having a plurality of ink ejection openings are also included.

[0020]

According to the present invention, since a plurality of discharge ports and liquid passages and an array of energy generating means and driving means are symmetrically provided on both surfaces of one substrate, a plurality of sets of recording means are provided. In this case, it is possible to provide an ink jet recording apparatus with a small space by reducing the size of the recording head, and it is advantageous in controlling the temperature of two sets of recording means at the same time. In particular, dark and light ink is used. An inkjet recording apparatus having an inkjet recording head suitable as a full-color printer can be provided.

In the ink cassette according to the present invention, since a buffer chamber in which liquid bubbles are trapped by a filter is provided in a part of the ink storage section which cannot prevent the ink flow path leading to each nozzle, it is possible to set an arbitrary value. The vibration generated by the foaming of the nozzle is absorbed in the buffer chamber,
It does not affect the operation of other nozzles.

[0022]

Embodiments of the present invention will be described in detail and specifically below with reference to the drawings.

1 and 2 show an example of the construction of an ink jet recording head according to the present invention. As shown in these figures, the recording head 1 of the present example has an array of ink ejection ports 3 at positions symmetrical with respect to one substrate 2 on both sides, and the substrate 2 is formed of, for example, an aluminum plate. 4 is a silicon substrate attached to both sides of the substrate 2,
On the silicon substrate 4, the electrothermal converter 5, the discharge port 3 formed by film formation, the forming wall 7 for the liquid passage 6, the electrode 8,
The top plate 9 and the like are formed by a semiconductor manufacturing process. Further, as shown in FIG. 2, each liquid path 6 communicates with a common liquid chamber 10, and an ink tube 12 is provided on an upper top plate 9 of the common liquid chamber 10 via a connector 11, respectively.
These ink tubes 12 from an ink tank (not shown)
Ink is supplied to the common liquid chamber 10 via the.

Further, the substrate 2 has the upper and lower ends shown in FIG.
The fins 13 for cooling and the heater 14 for temperature control as shown in FIG.
Is provided, and the temperature of the entire recording head 1 can be adjusted by cooling through the fins 13 by a fan (not shown) and heating by the temperature adjusting heater 14. The fan and the temperature adjustment heater 14 are driven according to a head temperature signal detected by a temperature detecting element such as a thermistor. As shown in FIG. 1, the temperature measuring element 15 in this embodiment is a silicon substrate 4
It is formed directly on top by film formation. By doing so, the temperature of the head can be controlled accurately without compromising the configuration of the recording head. Further, the heat radiating (cooling) fins 13 can be efficiently radiated by disposing on both sides of the substrate 2, and a part of the substrate 2 is preliminarily formed into a fin shape by a skiving process as in the present embodiment. By forming it, it is possible to reduce the thermal resistance between the fin 13 and the substrate 2 and perform more accurate temperature control.

FIG. 3 shows an outline of an ink jet recording apparatus using the present ink jet recording head. As described above, each recording head 1 shown here has a configuration in which the ejection port arrays are provided on both sides of the substrate 2, and one head 1 can record with two types of ink. In the present embodiment, three-value recording with light ink and dark ink is obtained for each of the four colors of cyan (C), magenta (M), yellow (Y), and black (Bk). 12 for each ink tank 21 and head 1
Are connected to supply ink to the head 1 side. Further, 20 is a head mounting carriage, 22 is an ink tank unit mounting carriage, the carriage 20 is driven by a belt 24 disposed between a motor driving pulley 23A and a driven pulley 23B, and the ink tank unit mounting carriage 22 is driven. Pulley 25A and driven pulley 25
It is moved by a belt 26 arranged between the belt B and the belt. Note that the printhead unit and the ink tank unit are thus mounted on the separate carriages 20 and 22 and driven individually, because the printhead side needs to be driven with high precision in order to prevent color misregistration. Therefore, it is necessary to reduce the weight and, on the other hand, the ink tank unit side does not need to be driven with such high precision.

On the other hand, the recording sheet 100 is fed by a roller 27 from a feeding system (not shown).
Then, recording is performed on the sheet 100 while being held by both rollers 28 and 27 in the process of being further fed to the sub-scanning roller 28. At this time, the setting is made such that the conveyance speed of the roller 27 is set to be slightly slower than the conveyance speed of the sub-scanning roller 28, and the conveyance force of the sub-scanning roller 28 is set to be larger than that of the sub-scanning roller 28. The recording sheet 100 can be kept flat with the roller 28. In this case, an air passage (not shown) may be provided in the platen 29, a large number of holes may be formed in the passage surface of the recording sheet 100, and the recording sheet 100 may be suction-held by a suction mechanism. Further, 30 is a recording head 1.
Is a recovery system for performing a recovery operation on the. The recovery operation may be any one of various known methods (suction method and pressurizing method). Reference numeral 31 denotes a wiping blade, which cleans the ejection port surface by contacting the edge of the blade 31 or its periphery with the ejection port surface. At this time, since the same blade comes into contact with all the head surfaces, there is a possibility that ink color mixing may occur.
Therefore, before recording on the recording sheet 100, the respective recording heads 1 perform idle ejection toward the absorber 32 to discharge the mixed color ink that may be formed in the liquid passage.

In the recording apparatus thus constructed, the recording by the recording head 1 is started from the left end of the sheet 100 in the figure, and when the recording is performed up to the right end of the sheet 100 as shown by the area line, the carriage 20 and the ink tank unit are mounted. The carriage 22 is returned to the left end, the recording sheet 100 is fed by one line by the sub-scanning roller 28, and recording is started on the next line.

FIG. 4A shows the relative position of the head 1 with respect to the recording sheet 100 when FIG. 3 is viewed from above.
Here, the row P of the arrow indicates the movement range of the carriage 20 when the head of the present invention is used, and the movement range in this case is indicated by L in the drawing. The Q column of arrows indicates the movement range of the carriage 200 when eight conventional recording heads of a color system using dark and light inks are arranged and main scanning is performed. As is clear from FIG. 4A, in the conventional case, an extra space for Lα and Lβ is required on both sides of L as compared with the present invention, which greatly hinders miniaturization. You can see that

Furthermore, the present invention also contributes to the simplification of the heat dissipation mechanism. That is, when recording is performed using dark and light ink, it is distributed to the image signal for light ink and the image signal for dark ink according to the light and dark distribution table as shown in FIG. Then, after being binarized, the image is sent to each print head driver (not shown) for image recording. As can be seen from FIG. 5, the peak of the light ink print head and the peak of the dark ink print head after the sorting are performed. , And the recording heads for light and shade are not driven at the same time (eg solid printing). Therefore,
According to the present invention, it is necessary to design the fins so that heat can be sufficiently dissipated from the heat generated at the time of full drive for each head, according to the present invention. By designing the fins required for full drive of one head, the heat dissipation mechanism can be simplified.

FIG. 4B shows another embodiment. This example shows an example of a conventional image forming apparatus that forms a binary image with only dark ink. In this case, each of the recording heads 1 configured as shown in FIGS. Inks of different colors (cyan and magenta) are supplied respectively, and full color is output by two heads. Even in the case of this example, it is possible to reduce the distance on the ejection surface for at least two colors handled in one head 1.
Since it is about / 5 to 1/10, the effect of suppressing the color shift between the two colors can be expected.

FIG. 8 shows still another embodiment. The basic structure of this embodiment is the same as that of FIG. That is,
A silicon substrate 4, an electrothermal converter 5, walls 7, and a top plate 9 are formed on both sides of the substrate 2. However, in FIG. 1, the discharge ports 3 formed on the left and right sides of the substrate 2 have the same size (cross-sectional area), but in the example of FIG. 8, the left and right discharge ports 3 have different sizes. The left outlet 3N is smaller than the right outlet 3W.

Therefore, by using the head 1 as in the present embodiment, for example, the same color ink is ejected from the ejection ports 3N-3W on both sides, a multi-valued image of area gradation can be obtained. In general, an inkjet recording apparatus having a water supply layer formed on the surface of a base paper called a coated paper is used, but there is also a so-called plain paper that forms an image by absorbing water only by the base paper. When such plain paper is used, the optimum inkjet diameters are usually different from each other. If the ejection port sizes of the head 1 are set to be suitable for coated paper and plain paper, the same device and the same sheet path are used. Good quality recording can be obtained on both coated paper and plain paper. (Others) The present invention described above is provided with a means (for example, an electrothermal converter or a laser beam) that generates thermal energy as energy used for ejecting ink, particularly in the inkjet recording system, The present invention brings about excellent effects in a recording head and a recording apparatus of the type in which the state of ink is changed by the heat energy. This is because such a system can achieve high density recording and high definition recording.

Regarding the typical structure and principle thereof, see, for example, US Pat. No. 4,723,129 and US Pat. No. 4,740.
What is done using the basic principles disclosed in 796 is preferred. This method is a so-called on-demand type,
Although it can be applied to any of the continuous type, in particular, in the case of the on-demand type, it can be applied to the sheet holding the liquid (ink) or the electrothermal converter arranged corresponding to the liquid path. By applying at least one drive signal corresponding to the recorded information and giving a rapid temperature rise exceeding nucleate boiling, heat energy is generated in the electrothermal converter, and film boiling occurs on the heat acting surface of the recording head. Cause
As a result, it is possible to form bubbles in the liquid (ink) that correspond one-to-one to this drive signal, which is effective. Due to the growth and contraction of the bubbles, the liquid (ink) is ejected through the ejection opening to form at least one droplet. It is more preferable to make this drive signal into a pulse shape, because the bubble growth and contraction are immediately and appropriately performed, so that the ejection of the liquid (ink) with excellent responsiveness can be achieved. As the pulse-shaped drive signal, those described in US Pat. Nos. 4,463,359 and 4,345,262 are suitable. If the conditions described in US Pat. No. 4,313,124 of the invention relating to the rate of temperature rise on the heat acting surface are adopted, more excellent recording can be performed.

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 which can be recorded by the recording apparatus. 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 recording head integrally formed.

In addition, even in the case of the serial type as in the above example, the recording head fixed to the main body of the apparatus or the electrical connection to the main body of the apparatus and the ink from the main body of the apparatus by being attached to the main body of the apparatus. 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 integrally provided in the recording head itself is used.

Further, it is preferable to add recovery means for the recording head, preliminary auxiliary means, and the like, which are provided in the present invention as a configuration of the recording apparatus, because the effects of the present invention can be further stabilized. . Specific examples thereof include capping means for the recording head, cleaning means, pressurizing or suctioning means, electrothermal converter or other heating element or preheating means by a combination thereof, It is also effective to perform stable recording by performing a preliminary discharge mode in which discharge is performed separately from recording.

In addition, in the above-described embodiments of the present invention, the ink is described as a liquid, but it is an ink that solidifies at room temperature or lower and that softens or liquefies at room temperature, or an ink jet system. In general, the temperature of the ink itself is adjusted within the range of 30 ° C. or higher and 70 ° C. or lower to control the temperature of the ink so that the viscosity of the ink is within the stable ejection range. Anything can be used. In addition, it is possible to prevent the temperature rise due to thermal energy from being positively used as the energy for changing the state of the ink from the solid state to the liquid state, or to use ink that solidifies when left standing for the purpose of preventing ink evaporation. In any case, the ink is liquefied by the application of the thermal energy according to the recording signal, and the liquid ink is ejected, or the one that has already started to solidify when reaching the recording medium,
The present invention is also applicable to the case of using an ink which has a property of being liquefied only by heat energy. The ink in such a case is in a state of being held as a liquid or a solid in the concave portion or the 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.

In addition, as a form of the recording apparatus provided with the recording mechanism using the liquid jet recording head of the present invention, besides the one used as an image output terminal of information processing equipment such as a computer, it is combined with a reader or the like. Copier,
Further, it may be a facsimile device having a transmitting / receiving function.

Next, an embodiment of the ink cassette of the present invention will be described with reference to the drawings.

FIG. 9 is a first embodiment of the ink cassette of the present invention.
It is a partial explanatory view seen from the upper part of.

This ink cassette includes a nozzle portion 1a, liquid chambers 4a and 4b, an ink supply pipe 55, and a filter 88.
And has a heater board 99. Nozzle 1a,
The ink supply pipe 55 is the same as the nozzle portion 41 and the ink supply pipe 45 of the conventional ink cassette. The filter 88 divides the liquid chamber into the liquid chamber 4a and the buffer chamber 4b, and the liquid bubbles spontaneously generated in the liquid chamber 4a are not required.
Although it passes through b, it prevents the liquid bubbles generated in the buffer chamber 4b from having a predetermined size or more from passing through to the liquid chamber 4a, and prevents the liquid bubbles from entering the liquid chamber 4a and closing the nozzle. Liquid chamber 4a
Is an ink storage unit for temporarily storing the ink sent from the ink tank via the ink supply pipe 55 and flowing it to the nozzle unit 1a. The heater board 99 does not serve as a buffer when the liquid bubbles in the buffer chamber 4b disappear, so that the heater board 99 is energized in a predetermined cycle to forcibly generate the liquid bubbles.

Vibration generated when foaming is generated in any nozzle of the nozzle portion 1a is transmitted to the liquid chamber 4a, but is not absorbed in the buffer chamber 4b in which the liquid bubble is contained and is not transmitted to other nozzles. .

FIG. 10 is a partial explanatory view of the second embodiment of the ink cassette of the present invention seen from the upper surface.

This ink cassette is used in the first embodiment shown in FIG.
The heater board 99 is excluded from the above, and naturally generated liquid bubbles are confined in the buffer chamber 4b.

FIG. 11 is a partial explanatory view of the third embodiment of the ink cassette of the present invention seen from above.

This ink cassette is the same as that of the first embodiment of FIG. 9, but the filter 33 is the filter 88 of the first embodiment.
Unlike the above, the size of the eye of the filter 33 is smaller than the size of the eye of the filter 88, and the liquid bubbles naturally generated in the liquid chamber 4a are not passed to the buffer chamber 4b but only the liquid bubbles generated in the buffer chamber 4b are confined. is there. The filter 33 naturally allows the ink to flow.

FIG. 12 is an external perspective view showing an example of an ink jet recording apparatus (IJRA) in which the recording head obtained by the present invention is mounted as an ink jet head cartridge (IJC).

This ink jet recording apparatus has an ink jet type recording head for recording by forming flying droplets by utilizing thermal energy among the ink jet recording methods, and provides excellent effects.

Regarding the typical structure and principle thereof, see, for example, US Pat. Nos. 4,723,129 and 4740.
No. 796, the present invention is preferably carried out using these basic principles. This recording method using an inkjet recording head can be applied to both so-called on-demand type and continuous type.

To briefly explain this recording method, the electrothermal converter arranged corresponding to the sheet or liquid path holding the liquid (ink) is changed to the liquid (ink) corresponding to the recording information. Heat energy is generated by applying at least one driving signal for giving a rapid temperature rise that causes the film boiling phenomenon beyond the nucleate boiling phenomenon, and causes the film boiling on the heat acting surface of the recording head. . In this way, bubbles can be formed from the liquid (hereinafter referred to as ink) in a one-to-one correspondence with the drive signal applied to the electrothermal converter, and this is particularly effective for the on-demand recording method. Ink is ejected through the ejection port by the growth and contraction of the bubbles to form at least one droplet. It is more preferable to make this drive signal into a pulse shape, because the bubble growth and contraction are immediately and appropriately performed, so that it is possible to discharge the ink with particularly excellent responsiveness. As the pulse-shaped drive signal, U.S. Pat. Nos. 4,463,359 and 4,345 are used.
Those as described in the '262 patent are suitable. If the conditions described in US Pat. No. 4,313,124, which is an invention relating to the rate of temperature rise on the heat acting surface, are adopted, more excellent recording can be performed.

The structure of the recording head is a combination of a discharge hole, a liquid flow path, and an electrothermal converter as disclosed in the above-mentioned specifications (straight liquid flow path or right-angled liquid flow path). In addition, as disclosed in U.S. Pat. No. 4,558,333 and U.S. Pat. No. 4,459,600, the present invention includes those having a configuration in which a heat acting portion is arranged in a bending region.

In addition, Japanese Laid-Open Patent Publication No. 123670/1984, which discloses a structure in which a common slit is used as a discharge port of a plurality of electrothermal converters, and a pressure wave of thermal energy is absorbed. The present invention is also effective in a structure based on Japanese Patent Laid-Open No. 138461/1984, which discloses a structure in which the corresponding opening corresponds to the discharge portion.

In FIG. 12, an ink jet head cartridge (hereinafter referred to as IJC) 60 is provided with a group of nozzles for ejecting ink so as to face the recording surface of the recording paper fed onto the platen 54. Carriage 16 is IJ
By holding C60 and connecting it to a part of the drive belt 58 that transmits the driving force of the drive motor 57, and making it slidable with the two guide shafts 59A and 59B arranged in parallel with each other, the IJC60 It is possible to move back and forth over the entire width of the recording paper.

The head recovery device 56 is arranged at one end of the movement path of the IJC 60, for example, at a position facing the home position. The head recovery device 56 is operated by the driving force of the cleaning motor 52 via the transmission mechanism 53, and the IJC 60 is capped. In association with the capping of the head recovery device 56 to the IJC 60 by the cap portion 56A, ink suction or IJC 60 by an appropriate suction means provided in the head recovery device 56.
The ink is pressure-fed by an appropriate pressurizing unit provided in the ink supply path to the ink, and the ink is forcibly discharged from the ejection port to perform the ejection recovery processing such as removing the thickened ink in the nozzle. In addition, the IJC 60 is protected by capping at the end of recording.

The blade 50 is a wiping member disposed on the side surface of the head recovery device 56 and made of silicon rubber. The blade 50 is held in a cantilever form by the blade holding member 51A, and like the head recovery device 56,
Operated by the motor 52 and the transmission mechanism 53, the IJC
It becomes possible to engage the discharge surface of 60. As a result, IJ
The blade 50 is projected into the movement path of the IJC 60 at an appropriate timing in the recording operation of the C 60 or after the ejection recovery process using the head recovery device 56, and the IJC
With the moving operation of the IJC 60, dew condensation, wetting, or dust on the ejection surface of the IJC 60 is wiped off.

Further, as a recording head to which the present invention is effectively used, there is a full line type recording head having a length corresponding to the maximum width of the recording medium which can be recorded by the recording apparatus. The full-line head may be a full-line recording head formed by combining a plurality of recording heads as disclosed in the above-mentioned specification, or a single full-line recording head integrally formed.

In addition, by being mounted on the apparatus main body, it can be electrically connected to the apparatus main body and can be supplied with ink from the apparatus main body by a replaceable chip type recording head or the recording head itself. The present invention is also effective when a cartridge-type recording head that is specially provided is used.

Further, it is preferable to add recovery means for the recording head, preliminary auxiliary means, etc. to the recording apparatus of the present invention because the recording apparatus of the present invention can be made more stable. Specific examples thereof include capping means, cleaning means, pressure or suction means, an electrothermal converter or a heating element other than this, preheating means for the recording head, recording means for the recording head, and recording means. It is also effective to perform stable recording by adding a means for performing a preliminary ejection mode for performing ejection different from the above.

Further, the recording mode of the recording apparatus is not limited to the mode in which only the mainstream color such as black is recorded, and either the recording head may be integrally formed or a plurality of combinations may be used. However, the present invention is also extremely effective for an apparatus provided with at least one of a multicolor of different colors or a full color by color mixing.

In the embodiment of the present invention described above,
Although description is made using liquid ink, in the present invention, either ink that is solid at room temperature or ink that is in a softened state at room temperature can be used. In the above-mentioned inkjet device, the temperature of the ink itself is generally adjusted within the range of 30 ° C. or higher and 70 ° C. or lower to control the temperature of the ink so that the viscosity of the ink is within the stable ejection range. Any liquid may be used as long as the ink is liquid.

In addition, the excessive temperature rise of the head or ink due to thermal energy is positively prevented by using it as the energy of the state change of the ink from the solid state to the liquid state, or the evaporation of the ink is prevented. It is also possible to use an ink that solidifies when left as it is. In any case, liquefaction occurs only when heat energy is applied, such as when the ink liquefies by applying heat energy according to the recording signal and is ejected as an ink liquid, or when it begins to solidify when it reaches the recording medium. The use of an ink having such a property is also applicable to the present invention.

Such an ink is disclosed in JP-A-54-568.
No. 47 or JP-A No. 60-71260, facing the electrothermal converter in the state of being held as a liquid or solid in the recesses or through holes of the porous sheet. It may be in the form.

In the present invention, the most effective one for each of the above-mentioned inks is one that executes the above-mentioned film boiling method.

[0064]

As described above, according to the ink jet recording apparatus of the present invention, a plurality of ink ejection openings, an array of liquid passages corresponding to the plurality of ink ejection openings, and the respective liquid passages are arranged. And an ink jet recording head in which two sets of recording means having energy generating means for ejecting ink from the ink ejection port and means for driving the energy generating means are symmetrically arranged on both surfaces of a support substrate. Therefore, by integrating two conventional heads into one head, the recording apparatus can be downsized and the temperature can be adjusted efficiently.

Further, in the ink cassette of the present invention, by providing the buffer chamber in which the liquid bubbles are confined in the liquid chamber, the vibration caused by the foaming generated in any nozzle is absorbed and the vibration to other nozzles is absorbed. The transmission of the ink is prevented, and the inconveniences such as the unstable amount of ink to be ejected next time, the deviation of the ink landing point, the disappearance of white streaks, and the appearance of black streaks are eliminated, and the reliability of the image is eliminated. It has the effect of improving the sex.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a configuration of a recording head according to the present invention.

FIG. 2 is a perspective view showing a configuration of a recording head according to the present invention.

FIG. 3 is a perspective view showing the configuration of an embodiment of the present invention.

FIG. 4 is an explanatory diagram showing a head moving range of two rows according to the present invention in comparison with a conventional example.

FIG. 5 is an explanatory diagram related to driving of two heads by a density distribution table.

FIG. 6 is a perspective view showing a partially broken configuration of a conventional inkjet recording head.

FIG. 7 is an explanatory diagram showing a moving range of a recording head according to a conventional serial scan method.

FIG. 8 is a sectional view showing another configuration example of the recording head according to the present invention.

FIG. 9 is a partial explanatory view of the first embodiment of the ink cassette of the present invention seen from above.

FIG. 10 is a partial explanatory view of the second embodiment of the ink cassette of the present invention as seen from above.

FIG. 11 is a partial explanatory view of the third embodiment of the ink cassette of the present invention seen from above.

FIG. 12 is an external perspective view showing an example of an inkjet recording apparatus in which the ink cartridge obtained by the present invention is mounted.

FIG. 13 is a perspective view of a conventional example of an ink cassette.

14 is a perspective view of a main part of the head chip 46 shown in FIG.

15 is an explanatory diagram of a head chip 46 shown in FIG.

[Explanation of symbols]

 1, 101 Recording Head 2 Substrate 3, 3N, 3W Ink Discharge Port 4 Silicon Substrate 5, 103 Electrothermal Converter 6 Liquid Path 7 Forming Wall 8 Electrode 9 Top Plate 11 Connector 12 Ink Tube 13 Cooling Fin 14 Heater 15 Temperature Measuring Element 16 , 20, 22, 200 Carriage 21 Ink tank 23A, 25A Drive pulley 23B, 25B Followed pulley 26 Belt 27 Roller 28 Sub-scanning roller 29 Platen 30 Recovery system 31, 50 Blade 32 Absorber 100 Recording sheet 102 Substrate 104 Electrode 105 Liquid path Wall 106 Top plate 108 Common liquid chamber 109 Ink supply pipe connector 110 Liquid passage 111 Discharge port 1a, 41 Nozzle portion 4a Liquid chamber 4b Buffer chamber 33,88 Filter 42 Heater board 44 Liquid chamber 45,55,107 Ink supply pipe 46 Head Chip 47 ink tanks 47a outlet 50 blade 51A blade holding member 52 for cleaning the motor 53 power transmission mechanism 54 platen 56 head recovery device 56A cap portion 57 drive motor 58 drive belt 59A, 59B guide shaft 60 the head cartridge (IJC) 99 heater board

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI Technical display location B41J 2/05 2/125 8306-2C B41J 3/04 101 A 9012-2C 103 B 9012-2C 104 K

Claims (9)

[Claims] 1. In an ink jet recording apparatus, a plurality of ink ejection ports, an array of liquid paths corresponding to the plurality of ink ejection ports, and each of the liquid paths are provided to eject ink from the ink ejection ports. Energy generating means for
An ink jet recording apparatus, wherein two sets of recording means having means for driving the energy generating means are provided with ink jet recording heads symmetrically arranged on both surfaces of a supporting substrate. 2. The ink jet recording apparatus according to claim 1, wherein the ink jet recording head has an electrothermal converter that generates thermal energy that causes film boiling of the ink, as an energy generating unit for ejecting the ink. 3. The inkjet recording apparatus according to claim 1, wherein the two sets of recording means are controlled in temperature and humidity by a common temperature and humidity adjusting means. 4. The ink jet recording apparatus according to claim 1, wherein the two sets of recording means eject different color tones or different kinds of colors. 5. An ink cassette having an ink tank, an ink ejection port, an energy generating unit for ejecting ink from the ink ejection port, and an ink storage unit between the ink ejection port and the ink tank. An ink cassette, characterized in that it has a filter that is provided inside the unit and prevents passage of liquid bubbles exceeding a predetermined size. 6. The ink cassette according to claim 5, wherein the energy generating means is an electric heater provided in an area, which is separated by a filter and does not include a discharge port, in the ink storage section. 7. The ink cassette according to claim 5, wherein the discharge energy of the ink discharge energy generating means is an electrothermal converter that generates heat energy. 8. The ink cassette according to claim 5, further comprising a full-line type ink jet recording head having a plurality of ink ejection openings provided over the entire width of the recording area of the recording medium. 9. An ink jet recording apparatus, comprising: the ink cassette according to claim 5, which is provided with at least an ink ejection port facing a recording surface of a recording medium; and a member for installing the ink cassette. An ink jet recording apparatus characterized by: