JPH05318718A - Ink jetting device - Google Patents

Abstract

PURPOSE:To remove defect in discharge including undischarge of a recording head by a method wherein both of a recovery amount by a recovery means and a number of recovery executions to a scan recovery of an ink jet means are set to specific values. CONSTITUTION:As initial values when an ink jetting device starts operation, initial time T is set at a value tau and a driving pulse P in discharging is set at a value PO. Then, in order to achieve stability for discharge, cleaning of a discharging surface by an air current and a blank discharge are successively carried out. Fudrther, after releasing capping, communication of an image data is carried out between a data transmitting origin and a printing control part of a recorder, and one scan content of the data of a recording head is inputted. After inputting the data, a head carriage and an ink carriage are moved forward with an independent carriage motor to carry out printing by a scan length to be printed. Whether or not recording of the image is allowed to be ended is judged at a home position, and when allowed to be ended, the recording head is capped.

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 for forming an image on a recording material according to an image signal or an original image.

[0002]

2. Description of the Related Art Recording devices such as copiers, printers, and facsimiles, which are used together with a computer or a word processor, or used alone, feed and convey a sheet-shaped recording material such as paper or resin thin plate. An image is recorded on the recording material based on an image signal. Such a recording device is classified into an inkjet system, a wire dot system, a thermal system, an electrostatic system, an electrophotographic system, and the like depending on the recording system. Among them, the inkjet recording apparatus using the inkjet method is one in which recording is performed by ejecting ink from a recording head, which is a recording unit, onto a recording material, and it is possible to record a high-definition image at high speed and to reduce noise due to non-impact. Therefore, there is an advantage that a color image can be easily recorded by using multicolor ink. In particular, a recording head that ejects ink by using thermal energy is an electrothermal converter formed on a substrate through a semiconductor manufacturing process such as etching, vapor deposition, and sputtering, an electrode, a liquid furnace wall, and a ceiling. By forming a plate or the like, it has a high-density ink ejection port and can be easily manufactured. On the other hand, with respect to the material of the recording material, in recent years, paper or resin thin plate which is a normal recording material, for example, OHP paper,
In addition, it has been required to use thin paper or processed paper, for example, punched paper for filing, perforated paper, paper of any shape, or woven cloth. Further, with respect to the size of the recording material, large-sized woven fabrics used for advertising papers, clothes, etc. have been demanded.

In a serial type ink jet recording apparatus in which a recording head is scanned in a direction intersecting with a conveyance direction of a recording material, after the recording material is set at a predetermined position,
An image is recorded by a recording head mounted on a carriage that moves along the recording material based on the image signal, and after one scan, that is, the recording of the recording width of the recording head is completed, the recording material is recorded by the recording width. The operation of transporting and then recording the image of the next row is repeated, and image recording of the entire recording material is performed. In such a serial type recording method, the recording head can be mounted on a small recording device that is easy to carry and install, and recording can be performed not only on a small size but also on a large-sized recording material that is long in the scanning direction of the recording head. It is also mounted on large machines and uses a common recording head to realize recording devices for various applications.

[0004]

However, in the above-mentioned prior art, when the one scanning distance of the recording head is increased with a large-sized recording paper, the inside of the ejection opening not used for image recording is filled with ink. If the ink is left for a long time as it is, the ink in the ejection port is dried or the viscosity increases, and as a result, ejection is not performed when the next ejection is performed. Also, when the print duty of the recorded image is low, almost no ejection is performed, and the same thing occurs. This becomes serious in a low humidity environment. In particular, in the case of a color image, since a plurality of recording heads corresponding to each color of a plurality of inks are used, even if ejection failure occurs only in a part, a defective image results. Further, if the recording head is driven to discharge in a state where there is no ink in the discharge port as described above, the recording head is not heated, and the liquid path inside the discharge port deteriorates.

The image signal is not sent during the operation of the recording head, but is sent in a standby state, but it takes time to process the image data from the computer or the reading system (reader) which is the source, In the case of an image having a long width in the scanning direction, the amount of data increases, the data transfer time is increased, and the waiting time of the recording head is increased. In this case as well, since the time during which the recording head is not ejected continuously increases, the same problem as described above occurs. If data communication can be performed even while the recording head is operating, the standby time will be shortened, but for that purpose the storage capacity must be increased, and even for images with a small amount of data, a large capacity is required. If a memory circuit is required, the cost will be high.

Further, although the tint of the ink is influenced by the ink temperature, the ink is naturally cooled while the recording head is on standby, so that the temperature of the ink for writing an image is low during one scanning, At the end, the temperature of the ink rises due to the ejection drive by the heater, and a temperature difference occurs between the ink ejected at the edges of the image, and as a result, a density difference appears on the image and the image quality deteriorates. When the print head is in a standby state for a long time and the print head is not driven for a long time, the density difference becomes more remarkable.

[0007] In addition, since the sender is a large computer to a personal computer or a reader that is an image reading system, and the images are various,
It is difficult to determine the recovery amount by anticipating these data amounts in advance. In a large-sized long width recording device, from the small size to the large size, from paper to resin film or woven cloth, in order to improve the versatility of the recording material, it is necessary to judge by the actual usage state of the head. desirable.

Japanese Patent Application Laid-Open No. 60-101054 describes that the recovery scale is changed according to the head down time. Has not been considered.

An object of the present invention is to solve the above problems and to take advantage of the serial type, which is particularly advantageous for large-sized devices, to improve recovery performance and eliminate ejection defects including non-ejection of a recording head. Is to provide.

[0010]

In an ink jet device of the present invention for solving the above problems, there is provided a waiting time detecting means for detecting a waiting time of the ink jet means for each scanning of the ink jet means, and an ink from the ink jet means. And a recovery means for recovering or preventing the ejection failure, according to the detection level by the standby time detection means,
Both the amount of recovery by the recovery unit and the number of executions of recovery by the recovery unit with respect to the number of scans of the inkjet unit are set.

Further, the ink jet apparatus of the present invention comprises a scanning distance detecting means for detecting the scanning distance of the ink jet means for each scanning of the ink jet means, and a recovery means for recovering or preventing defective ejection of ink from the ink jet means. According to the detection level of the scanning distance detecting means, both the amount of recovery by the recovering means and the number of executions of recovery by the recovering means with respect to the number of scans of the inkjet means are set. ..

Further, the ink jet apparatus of the present invention comprises a scanning time detecting means for detecting a scanning time of the ink jet means for each scanning of the ink jet means, and a recovery means for recovering or preventing defective ejection of ink from the ink jet means. According to the detection level of the scanning time detection means, both the recovery amount of the recovery means and the number of times of execution of the recovery by the recovery means with respect to the number of scans of the inkjet means are set. ..

[0013]

According to the present invention, the recovery operation is performed early on the recording means after the printing scan, and the continuous non-ejection time is shortened. Further, the standby time of the recording head or the scanning distance or the degree of recovery according to the scanning time is set.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An example of the ink jet device of the present invention will be specifically described with reference to the drawings.

(Embodiment 1) FIGS. 1 and 2 are drawings showing the principal part of an ink jet recording apparatus according to this embodiment, and FIG. 1 is a sectional view of the ink jet recording apparatus.
[FIG. 3] is a top view of a print scanning unit and a peripheral portion.

In these drawings, 1 is a recording apparatus main body, 2 is a long roll as a recording medium, 2a is a long recording paper wound around a roll 2, and 4 is a predetermined recording paper 2a. Cutters 3 and 5 for cutting each length of the recording paper, a pair of conveying rollers for conveying the recording paper, respectively, 6 is a drive roller for intermittently conveying a predetermined amount of the recording paper 2a and accurately positioning the printing position. , 9 are paper discharge units for the recording paper 2a. 1
Reference numeral 0 denotes a head carriage on which the recording head 13 is mounted, and is supported on the pair of scanning rails 11 so as to be capable of reciprocating.
Reference numeral 12 denotes a platen located opposite to the recording head 13 with the recording paper 2a interposed therebetween. The platen 12 prevents the recording paper 2a from floating during printing and keeps it flat.
In order to prevent contact with the air, it has a suction and suction means such as suction by air or electrostatic suction.

The recording head 13 includes a substrate on which a plurality of electrothermal converters for generating thermal energy used for ejecting ink and a drive circuit for driving the electrothermal converters are formed, and the plurality of substrates on the substrate. The discharge ports 13a and the liquid passages corresponding to the respective electrothermal converters, and a top plate for forming a common liquid chamber common to the respective liquid passages are laminated. Recording on the recording paper 2a is performed by energizing the electrothermal converter to eject ink from the ejection port 13a.

Reference numeral 14 is a supply unit for supplying ink to the recording head 13 via a tube by a pump, and is provided with an ink cartridge which can be replaced when the ink runs out,
The ink carriage reciprocates on the rail 11 together with the head carriage 10.

Reference numeral 15 is a recovery unit for making the recording head 13 always printable, which is a cause of instability of ink ejection. (1) Increase in ink viscosity (2) Adhesion of ink to ejection port surface (3) The purpose of this is to remove or prevent residual bubbles in the discharge port, etc. and to obtain reliable discharge stability, and has the following members and mechanisms.

(A) Cap portion 15a: When the recording head is left in the air for a long time, the ink in the ejection port evaporates and the viscosity increases, and the ejection becomes unstable. In order to prevent this, during non-printing, the discharge port is shut off from the outside air (see FIG. 10). Inside the cap, there is a liquid absorbing material 15e (see FIG. 10) kept in a wet state with the ink, and the inside of the cap is kept at high humidity to minimize the thickening of the ink.

(B) Pressurization of ink: When the ink is left for a long time, the ink in the ejection port, even with a cap, is slow but evaporates and thickens. In addition, air bubbles may remain inside the discharge port to prevent stable discharge.
Therefore, at the start of printing, the pump provided in the supply unit 14 is driven to pressurize the ink, and the thickened ink inside the discharge port and residual bubbles are discharged to the outside of the discharge port. This also has the effect of cleaning dust and fluff on the surface of the discharge port, and even if dust or the like has entered the discharge port, to keep stable discharge.

(C) Air flow: After pressurizing the ink, the ink ejected from the ejection port remains on the surface of the ejection port. If the ink remains adhered, the ejected ink absorbs the ejected ink, causing a deviation in the ejection direction, or lowering the ejection speed to lower the accuracy of landing of the flying ink. Therefore, after pressurizing the ink, the air nozzle 15d (see FIG.
(See 0), an air flow is blown toward the surface of the ejection port to blow the ink to the lower part of the recording head. The liquid absorbing material 15e (see FIG. 10) is in contact with the lower portion of the recording head, and the flowed ink is absorbed by the liquid absorbing material.

(D) Idle ejection: When the print duty of a recorded image is low, ink is almost not ejected during printing depending on the ejection port, which may cause ink thickening due to evaporation. In order to prevent this, a predetermined drive pulse is given before the start of printing, ink is ejected to all ejection ports, and so-called aging is performed. Capping may be performed to enhance the wet state of the atmosphere around the discharge port.

By the recovery operation (c), (d), the absorbing material 15
The ink absorbed by e (see FIG. 10) is in the tube 15f.
(See FIG. 10) and is sent to a waste ink bottle provided below the recovery unit 15.

(E) Blade 15b: When ink mist generated by ink ejection adheres to the surface of the ejection port, ejection becomes unstable. To prevent this, a rubber blade that wipes the surface of the discharge port to clean it is provided. Further, it has a solenoid 15c for moving the blade 15b into and out of the discharge port surface.

Reference numeral 16a denotes a home position sensor for detecting a capping position and a standby position, which are home positions of the head carriage 10 outside the print area.
Reference numeral b is a registration sensor that determines the print start position when the recording head 13 is scanned.

FIG. 3 and FIG. 4 are examples of the printing operation flowchart of this recording apparatus. The printing operation of this apparatus will be described with reference to FIGS. The recording paper 2a supplied from the roll 2 is conveyed until the leading end of the recording paper 2a is nipped by the driving roller 6, is temporarily stopped, and is sucked and adsorbed by the platen 12. After that, the printing operation is started. First, as the initial value, the waiting time T is set to the value τ and the drive pulse P at the time of idle ejection is set to the value P0. The value τ is a time value that is shorter than the maximum time (hereinafter, referred to as firing time) that does not impair the ejection stability with respect to the time the recording head is left in the air, and is usually 1/2 or less of the firing time. The value P0 is the number of aging pulses, usually a few hundred values.

Then, in order to achieve ejection stability, ink pressurization, cleaning of the ejection port surface by an air flow, and idle ejection are sequentially performed. At this time, the ejection port 13a of the recording head 13 is capped by the cap portion 15a, and the home position sensor 16a causes the head carriage 1 to move.
It is detected that 0 is capped at the regular position. Next, capping is released and the image data input waiting state is entered. Here, when the image data is not input even after the elapse of a certain period of time, the operation returns to the capping state, avoids leaving the recording head 13 for a long time, and restarts the operation. This fixed time is set to a value slightly smaller than the above-mentioned one-hour firing in consideration of the operation time of each member.

Next, image data communication is performed between a data transmission source such as a computer or a reader and the print control unit of the recording apparatus 1, and data for one scan of the recording head 13 is input. The communication time during this period is detected as the waiting time of the recording head 13 by the measuring circuits operating in parallel at the time of data input according to the waiting time measuring flow shown in FIG. The waiting time T is the duration of the detection state of the home position sensor 16a after the cap is released,
Data input for one scan is completed, and head carriage 1
It is determined by sequentially adding the increment time δ to the initial value τ until 0 moves. The increment time δ may be set in advance to, for example, one period of a continuous periodic rectangular pulse wave.

After inputting the data, the head carriage 10 and the ink carriage 14 move forward in the direction of arrow A at a constant speed by independent carriage motors, respectively, and the registration sensor 1
The timing of the print start position is determined by 6b, and printing is performed for the ejection port array length of the recording head 13 (for the printing width) and the scanning length for printing. When the image recording for this one scan is completed, the head carriage 10 and the ink carriage 14 return to their original positions (home positions). At this time, the recording paper 2a is conveyed by the drive roller 6 by the print width and stopped again. Further, at the time of the backward movement, the blade 15b is provided so as to project at a position invading the ejection opening 13a, and the ink mist adhering to the ejection opening surface is wiped by the ink ejection at the time of printing to clean the ejection opening. .. In addition, when the carriage moves forward, the solenoid 15c
As a result, the blade 15b is retracted, and is in a position where it does not contact the discharge port 13a.

At the home position, it is judged whether or not the image recording is completed, and if it is completed, the recording head 13 is completed.
To end the printing operation. On the other hand, if continuous image recording is to be performed on the image data, the magnitude of the standby time T with respect to the preset reference time T0 is determined and used as an index of the ejection stability of the recording head 13.
As a matter of course, the reference time T0 is a value shorter than one hour from departure. Here, when the waiting time T <reference time T0, it is left in the air for a short time, and it is assumed that there is ejection stability. Normally, the number of aging pulses P is set to P0 and idle ejection is performed, and the state before the image data input is restored. The same printing operation as described above is repeated. Note that the value τ is substituted for the initial value for detecting the waiting time T, as at the start of the operation. When the standby time T> reference time T0, it is determined that the discharge time is long and the ejection stability is impaired, and the recording head 13 is immediately stopped.
Is capped and immersed in a wet atmosphere, the aging pulse number P is replaced with P1 (> P0) to return to the state before the idle discharge, and thereafter, the same printing operation as described above is repeated. By giving P1 larger than P0, the total ejection drive of the recording head 13 is enhanced and the ejection stability is restored. In this way, by comparing the standby time T of the recording head 13 with the reference time T0 and setting the degree of recovery of the recording head 13, the standby time of the recording head for communication that fluctuates depending on the input image data amount. An efficient and adaptive recovery operation can be performed according to the length, and the versatility of the image recording apparatus is expanded.

When the image recording of the entire image data is completed as described above, the recording paper 2a is cut into a predetermined length by the cutter 3, and the recording paper 2a is ejected from the paper ejection unit 9 to a paper ejection tray outside the apparatus. To be done.

When a sheet-shaped recording paper is selected as the recording material, the recording paper stocked in the cassette 7 passes through the guide and conveyance guide portion 8 and immediately before the conveyance roller 5 and the above-mentioned roll. The printing operation is the same as that described above, as it merges with the conveyance path from 2. In the case of sheet-like recording paper, it is cut into a predetermined size in advance, so the above-mentioned cutter 3
The action by is not required.

(Embodiment 2) The above is a description of the case of detecting the waiting time of the recording head. Next, an embodiment of detecting the scanning distance or the scanning time of the recording head will be described. As with FIG. 2, FIG. 5 is a top view of the print scanning portion and the peripheral portion.
A plurality of position sensors 18a for detecting the position of 0
18h is provided. FIG. 6 shows a printing operation flowchart. The configuration of the apparatus main body is almost the same as that described with reference to FIGS. 1 and 2, and redundant description will be omitted. However, when performing image recording for one scan, the position sensors 18a-1
With 8h, the backward movement point of the recording head 13 is detected, the distance between the home position and the backward movement point is calculated, and the scanning distance L is measured. After the image recording for one scan is completed, the preset reference distance L0 is compared with the scanning distance L. The reference distance L0 is determined in consideration of the reciprocating movement of the carriage 10. As a result, if the scanning distance L <the reference distance L0, the continuous non-ejection time of a certain ejection port is short, and thus ejection stability is usually normal, and it may be restored before image data is input. On the other hand, if L> L0, then the ejection becomes unstable, so it is necessary to perform capping at an early stage and perform a recovery operation with the aging pulse number P increased.

The scanning distance of the head carriage may be measured by coupling a rotary encoder to the rotary shaft of the carriage motor without depending on the above-mentioned sensor.

The head carriage 10 accelerates and decelerates during slow-up and slow-down, but it takes a short time, and it can be considered that the head carriage 10 has a constant speed during forward movement (during printing) and backward movement. The scanning time of the recording head 13 can be detected from the distance between the home position and the return point. Also in this case, the recovery operation setting may be performed by comparing the scanning time T'and the reference scanning time T0 'in exactly the same manner as described above.

Even if the recording paper is long in the scanning direction, not every scan prints an image in the full width, and there is also a discharge port that does not discharge ink during one scan. This is particularly the case when a character image, a single ruled line image, or an image of a specific color is recorded in a color image. In this way, by detecting the scanning distance or the scanning time to judge the ejection stability, it is possible to minimize the continuous non-ejection time of the ejection port, which varies depending on the recorded image, and it is possible to perform an effective recovery operation.

FIG. 7 is a flow chart of the printing operation when the non-capping time T + T 'which is the sum of the waiting time T and the scanning time T'is compared with the reference time T0.
Since the ejection stability is judged by the total time during which the recording head is not capped, it is the most severe condition and can be applied to any image.

(Embodiment 3) FIG. 8 shows another recovery operation setting after comparison of waiting times. Further divide the reference time into T1
(> T0) and T2 (> T1) add P2 (> P1) and P3 (> P2) to the setting of the number of aging pulses,
It has been used a lot. Also, after comparison with reference time T2, T>
If T2 is reached and more recovery is needed,
The state before the pressurization of the ink is returned, the pressurization of the ink and the cleaning by the air flow are added, and a careful recovery in the print operation start state is performed. In this way, by dividing the reference time, it is possible to provide an image recording apparatus according to various types of transmission sources and data amounts.

(Embodiment 4) FIG. 9 shows an embodiment in which recovery units are provided at both ends of the recording area. 15 is called a first recovery unit and 19 is called a second recovery unit. Although the configuration of each part of the unit is almost the same, the positions of the blade 19b, the second home position sensor 20a, and the registration sensor 20b of the second recovery unit 19 are mirror images of the first recovery unit 15. At the end of image recording for one scan, the position sensors 18a to 18h detect the position of the head carriage 10, and the carriage 10 moves to the shorter distance between the first home position and the second home position. Since the scanning distance or the scanning time is shortened, the ejection stability is not impaired, the number of aging pulses is not increased, and the amount of idle ejection ink to be discharged can be suppressed. Further, it is desirable to perform the capping early, and it is possible to shorten the moving time to the home position, which is advantageous in the case of performing the recovery early.

(Embodiment 5) FIGS. 10 (a) and 10
(B) shows the capping state of the recording head and the cap portion. In addition to the air nozzle 15d described with reference to FIG. 1, the cap portion 15a has an outlet 2 for ejecting an ink flow to the upper portion.
1 is provided. At the time of recovery operation when the ejection stability of the recording head 13 is significantly impaired, clear ink which has the same physical properties such as viscosity and surface tension but does not contain dye is pumped up and discharged through the tube 21a to the outlet 2
Pour from No. 1 to the surface of the discharge port and forcibly wash out. Since the clear ink has the same physical properties as the printing ink, it does not damage the ejection port. The operation sequence is such that the ink that bleeds on the surface of the ejection port due to the pressurization of the ink is washed away with the clear ink, and finally the clear ink remaining on the surface is blown off by the air flow. When printing on a recording material that is prone to fluff and dust such as woven cloth, these impurities adhere to the surface of the ejection port, so cleaning with an ink flow is effective in addition to ink pressurization and air flow. Is.

FIG. 11 shows a cap portion 15a as a recovery means.
It is drawing which shows the case where the absorber unit 22 is provided in the side. If the recovery operation by the ink flow described above is not sufficient, the head carriage 10 is moved to the position of the absorber 22a, and a further recovery operation is performed. FIG. 12A and FIG. 12B are configuration diagrams of the absorber unit 22. 22
Reference numeral a denotes a cylindrical elastic porous absorber, which is in contact with the discharge port surface with a predetermined pressure contact force during the recovery operation. The absorber 22a is supported by a holder 22b by a shaft 22g, and a pulley 22c and a holder 22 are provided at the end of the shaft 22g.
A motor 22e is provided at b, and a belt 22d is suspended between the pulley 22c and the motor 22e. Also,
A lead screw 22h integrally having a gear portion at its end is engaged with the holder 22b, and the gear portion is meshed with an elevating motor 22f. 22i is a holder 22b
Is a guide shaft for restricting the rotation of and for guiding up and down.
The lift motor 22f moves the holder 22b up and down,
At the same time, the absorber 22a is rotated by the motor 22e and moves up and down while rotating along the surface of the ejection port to suck out the ink in the ejection port and wipe the surface of the ejection port.
The absorber 22a is elastic and does not damage the ejection surface. Performing such suction and wiping at the same time is more effective. Further, as shown in FIG. 12 (a), it is more effective if the absorber 22a is rotated in the direction of the arrow B at the time of descending to rub the surface of the discharge port.

The present invention provides excellent effects particularly in a recording head and a recording apparatus of the type which ejects ink by utilizing thermal energy among the ink jet recording systems.

Regarding its typical structure and principle, see, for example, US Pat. Nos. 4,723,129 and 4740.
What is done using the basic principles disclosed in 796 is preferred. This method can be applied to both the so-called on-demand type and continuous type, but especially in the case of the on-demand type, a liquid (ink) is used.
By applying at least one drive signal that corresponds to the recorded information and gives a rapid temperature rise exceeding nucleate boiling, to the electrothermal converter arranged corresponding to the sheet or liquid path in which is held, This is effective because heat energy is generated in the electrothermal converter to cause film boiling on the heat acting surface of the recording head, and as a result, bubbles can be formed in the liquid (ink) in a one-to-one correspondence with this drive signal. The liquid (ink) is ejected through the ejection openings 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 the ejection of the liquid (ink) with excellent responsiveness can be achieved. As the pulse-shaped drive signal, U.S. Pat. Nos. 4,463,359 and 43,
Those as described in 45262 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.

As the constitution of the recording head, in addition to the combination constitution of the ejection port, the liquid passage, and the electrothermal converter (the linear liquid passage or the right-angled liquid passage) as disclosed in the above-mentioned respective specifications. US Pat. No. 4,558,333 and US Pat. No. 4, which disclose a configuration in which a heat acting portion is arranged in a bending region.
The structure using the specification of 459600 is also included in the present invention. In addition, Japanese Laid-Open Patent Publication No. 123670/1984 discloses a configuration in which a common slit is used as a discharge portion of a plurality of electrothermal converters, and an opening for absorbing a pressure wave of thermal energy. The present invention is also effective as a configuration based on JP-A-59-138461, which discloses a configuration that corresponds to the discharge portion.

Further, a full line type recording head having a length corresponding to the width of the maximum recording medium which can be recorded by the recording apparatus is obtained by combining a plurality of recording heads as disclosed in the above-mentioned specification. Although the structure may be one that satisfies the length or one recording head integrally formed, the present invention can more effectively exhibit the above-described effects.

In addition, by being attached to 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., which are provided as a configuration of the recording apparatus of the present invention, because the effects of the present invention can be further stabilized. Specifically, these are capping means, cleaning means, pressurizing or suctioning means, electrothermal converters or heating elements other than these, or preheating means for the recording head. ,
It is also effective to perform stable recording by performing a preliminary discharge mode in which discharge different from recording is performed.

Further, the recording mode of the recording apparatus is not limited to the recording mode of only the mainstream color such as black, but the recording head may be integrally formed or a plurality of combinations may be used. The present invention is also extremely effective for a device provided with at least one of full color by color mixing.

In the embodiments of the present invention described above, the liquid ink is used for the description. However, in the present invention, either an ink which is solid at room temperature or an ink which is in a softened state at room temperature is used. 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, it is possible to prevent the temperature rise due to thermal energy from being positively used as energy for changing the state of the ink from a solid state to a liquid state, or to use an ink that solidifies when left standing for the purpose of preventing ink evaporation. However, in any case, by applying heat energy such as ink that is liquefied by being applied according to a recording signal of heat energy and ejected as an ink liquid or that has already started to solidify when it reaches the recording medium. The use of an ink having a property of liquefying for the first time is also applicable to the present invention. In such a case, the ink is retained as a liquid or solid in the recesses or through holes of the porous sheet as described in JP-A-54-56847 or JP-A-60-71260, 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.

[0051]

As described above, the present invention is provided with means for detecting the waiting time or the scanning distance or the scanning time of the recording head for each scanning of the recording head, and the ejection stability of the recording head is stabilized by the detected value. The degree of recovery is determined and the degree of recovery operation is set according to the degree of recovery, so recovery operation is performed according to the diversified original image (image data) or long recording material, and efficient ejection is performed. Can maintain stability.

In particular, in a large-sized recording apparatus, printing is performed on recording paper of a small size to a large size, so that ejection stability can be guaranteed for each size and each recorded image.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of an inkjet recording apparatus of the present invention.

FIG. 2 is a top view showing a recording head scanning unit and a peripheral portion.

FIG. 3 is a flowchart of a printing operation in consideration of a waiting time.

FIG. 4 is a flowchart of a printing operation in consideration of a waiting time.

FIG. 5 is a top view of a scanning unit and a peripheral portion when a plurality of position sensors are arranged.

FIG. 6 is a flowchart of a printing operation when a scanning distance is considered.

FIG. 7 is a flowchart of a printing operation when a standby time and a scanning distance are taken into consideration.

FIG. 8 is a printing operation flowchart in the case where the set value of the recovery operation is subdivided.

FIG. 9 is a top view of the scanning section and the peripheral section in the case where recovery means is provided at both ends of the recording area.

10 (a) and 10 (b) are cross-sectional views showing the cap portion of the recovery unit.

FIG. 11 is a top view of a scanning unit and a peripheral portion when a wiping unit is provided.

FIG. 12A and FIG. 12B are schematic diagrams showing the wiping unit.

[Explanation of symbols]

 10 Head Carriage 13 Recording Head 13a Ejection Port 15a Cap 15b Blade 16a Home Position Sensor 18a-18h Carriage Position Sensor 22a Absorber

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁵ Identification number Office reference number FI technical display location B41J 2/05 29/00 29/20 8804-2C 8306-2C B41J 3/04 102 Z 9012-2C 103 B 8804-2C 29/00 U

Claims (13)

[Claims] 1. A standby time detection unit that detects a standby time of the inkjet unit for each scan of the inkjet unit; and a recovery unit that recovers or prevents defective ejection of ink from the inkjet unit. An inkjet apparatus, wherein both the amount of recovery by the recovery unit and the number of times of execution of recovery by the recovery unit with respect to the number of scans of the inkjet unit are set according to the detection level of the standby time detection unit. 2. A scanning distance detecting means for detecting a scanning distance of the ink jet means for each scanning of the ink jet means is further provided, and the scanning distance detecting means and the waiting time detecting means detect the scanning distance. 2. The inkjet apparatus according to claim 1, wherein both the amount of recovery by the recovery unit and the number of times of execution of recovery by the recovery unit with respect to the number of scans of the inkjet unit are set. 3. A scanning time detecting means for detecting a scanning time of said inkjet means for each scanning of said inkjet means is further provided, and according to a detection level by said scanning time detecting means and said standby time detecting means, 2. The inkjet apparatus according to claim 1, wherein both the amount of recovery by the recovery unit and the number of times of execution of recovery by the recovery unit with respect to the number of scans of the inkjet unit are set. 4. A scanning time detecting means for detecting a scanning time of the inkjet means for each scanning of the inkjet means, further comprising: the scanning time detecting means, the scanning distance detecting means, and the waiting time detecting means. 3. The inkjet apparatus according to claim 2, wherein both the amount of recovery by the recovery unit and the number of times of execution of recovery by the recovery unit with respect to the number of scans of the inkjet unit are set according to the detection level. 5. The ink-jet means scans in a direction intersecting the conveyance direction of the recording material and ejects ink onto the recording material when the recording material conveyed intermittently is stopped. The inkjet apparatus according to claim 1, wherein an image is formed. 6. The inkjet apparatus according to claim 1, wherein the inkjet means ejects the ink by utilizing thermal energy. 7. A scanning distance detecting means for detecting a scanning distance of the inkjet means for each scanning of the inkjet means, and a recovery means for recovering or preventing defective ejection of ink from the inkjet means, An inkjet apparatus, wherein both the amount of recovery by the recovery unit and the number of executions of recovery by the recovery unit with respect to the number of scans of the inkjet unit are set according to the detection level by the scanning distance detection unit. 8. A scanning time detecting means for detecting a scanning time of said inkjet means for each scanning of said inkjet means is further provided, and according to a detection level by said scanning time detecting means and said scanning time detecting means, 8. The inkjet apparatus according to claim 7, wherein both the amount of recovery by the recovery unit and the number of executions of recovery by the recovery unit with respect to the number of scans of the inkjet unit are set. 9. The ink jet means scans in a direction intersecting with the conveying direction of the recording material when the recording material conveyed intermittently is stopped, and ejects ink to the recording material. The ink jet apparatus according to claim 7, which forms an image. 10. The ink jet apparatus according to claim 7, wherein the ink jet means ejects the ink by utilizing thermal energy. 11. A scanning time detecting means for detecting a scanning time of the inkjet means for each scanning of the inkjet means, and a recovery means for recovering or preventing defective ejection of ink from the inkjet means, An inkjet apparatus, wherein both the amount of recovery by the recovery unit and the number of times of execution of recovery by the recovery unit with respect to the number of scans of the inkjet unit are set according to the detection level of the scanning time detection unit. 12. The ink jet means scans in a direction intersecting with a conveyance direction of the recording material to eject ink onto the recording material when the recording material conveyed intermittently is stopped. The image formation is performed.
Inkjet device. 13. The ink jet apparatus according to claim 11, wherein the ink jet unit ejects the ink by utilizing thermal energy.