JPH07256896A - Device and method for controlling driving of ink jet record head - Google Patents

Abstract

PURPOSE:To provide a device and a method for controlling the driving of an ink jet record head capable of performing a high speed and stable recording without reducing the quality of the recording on a record medium. CONSTITUTION:A recording device comprises a means 42 for setting a pulse condition of a pulse signal by which a record head 10 is driven, a means 43 for storing the pulse condition, a means 41 for counting the number of dots recorded by each of first-(n)th record regions divided in the scanning direction and a means 17 for detecting a temperature of the record head. The pulse condition for the recording of the first record region is determined based on the detected temperature by the pulse condition setting means before scanning the first record region and the pulse conditions for the other record regions are determined based on the pulse condition and the number of dots of the just previous record region.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drive control device and a drive control method for an ink jet recording head, and more specifically, it allows fine ink droplets to fly and land toward a recording medium.
The present invention relates to a drive control device and a drive control method for an inkjet recording head that obtains a recorded image.

[0002]

2. Description of the Related Art Conventionally, ink in an ink discharge port and a liquid path (hereinafter, both are collectively referred to as a nozzle) communicating with the ink is heated by a heating means such as a heater to generate bubbles, and the action of the bubbles. A so-called bubble jet recording head is widely known in which minute ink droplets are ejected from an ink ejection port onto a recording medium to obtain a recorded image on the recording medium, and the so-called bubble jet recording head is applied to a printer, a copying machine, or the like. Has been done.

Recording by such a bubble jet recording head is suitable for high speed and high image quality because it is easy to realize multi-nozzles and high density of nozzles. Particularly, by using multi-nozzles and increasing the driving frequency of the recording head. Many attempts have been made to improve the recording speed of printers, copiers and the like.

By the way, in order to achieve high speed by using multiple nozzles and increasing the driving frequency of the recording head, it is necessary to prevent an increase in the ejection volume of the ink droplets due to the temperature rise of the recording head, or else the recording target The density of the recorded image obtained on the body gradually rises as the recording progresses, resulting in image bleeding and line thickening, and when applied to color recording, bleeding between inks between colors (bleeding).
And significantly deteriorates the printing quality. Further, the extreme temperature rise hinders continuous and stable bubble generation (foaming), resulting in image loss due to non-ejection of ink droplets.

Therefore, it has been conventionally proposed that the recording head is set to a temperature higher than the operating environment temperature of the apparatus in advance, and control is performed so as to suppress the change width of the head temperature increase due to recording as much as possible.

[0006]

However, such control inevitably raises the temperature when an image is printed with a print signal having a high duty ratio, and causes an increase in density due to an increase in ejection volume.

Therefore, there has been disclosed a method in which the recording head is provided with a temperature detecting means and the thermal energy applied to the recording head is changed according to the detection result of the temperature detecting means to keep the ejection volume constant. According to this plan, for example, a drive pulse for driving an electrothermal conversion element (hereinafter referred to as a heater) provided for generating heat energy in a recording head is divided into two and given to record the first pulse width. By making the head short when the temperature of the print head is high and lengthening it when the temperature of the print head is low, the discharge volume can be made constant regardless of the temperature of the print head.

By the way, in order to detect the temperature of the recording head sequentially and accurately, it is necessary to provide temperature detecting means in the vicinity of the heater in the nozzle, and in the case of a recording head having a small number of nozzles, for example, both ends of the nozzle row are provided. The temperature of the recording head can be detected by the temperature detecting means provided in
When the number of nozzles is large, it is difficult to detect an accurate temperature in correspondence with various temperature distributions in the recording head only by the temperature detecting means provided at both ends. Further, the temperature detected by the temperature detecting means has a time delay with respect to the temperature rise of the heater itself, and the detection accuracy decreases as the number of nozzles increases, making it difficult to detect an accurate temperature. Further, it is possible to provide the temperature detecting means not only at both ends of the nozzle row but also in the central part, but this hinders high density of the nozzles, and the number of output terminals in the recording head increases, so that the recording head becomes large and the apparatus becomes large. Not suitable for miniaturization.

Furthermore, in order to detect the temperature of the recording head relatively accurately even if the number of nozzles is large, the number of recorded dots (pixels) is counted, and the temperature rise amount of the recording head is calculated from the counted result. Has been proposed to control so as to change the pulse width applied to the heater.

According to such control, since the temperature increase is calculated based on the number of recorded dots, it is possible to control the discharge volume more accurately and more accurately than the detection method by the temperature detecting means.

However, if only the above-mentioned control is performed, there are variations in the manufacturing characteristics of the recording heads, which makes it difficult to deal with the case where the patterns having the same temperature rise characteristics are different for each recording head. That is, when the characteristics of the temperature rise are different for each print head, it is necessary to change the calculation formula and the parameter for calculating the temperature rise from the number of dots of the print for each print head. The above characteristics must be inspected before mounting on the recording apparatus, and in either case, the number of man-hours increases and the cost increases, which is not preferable.

The object of the present invention is to solve the above-mentioned problems of the prior art, and to improve the recording quality obtained on the recording medium when the recording head is made multi-nozzle and the driving frequency is increased to increase the speed. To provide and provide a drive control device and a drive control method for an ink jet recording head, which can perform stable recording without lowering.

[0013]

In order to achieve such an object, a drive control device for an ink jet recording head according to the present invention comprises pulse condition setting means for setting a pulse condition of a pulse signal supplied to the recording head, and Pulse condition storage means for storing pulse conditions, counting means for counting the number of dots recorded in each of the first to nth recording areas divided in the scanning direction of the recording head, and the temperature of the recording head are detected. And a pulse condition in the first recording area based on the temperature detected by the temperature detecting means before the scanning of the first recording area is performed by the pulse condition setting means. The pulse condition in the second to nth recording areas is controlled to be set based on the pulse condition set in the recording area immediately before and the number of dots. Is shall.

Further, in the ink jet recording head drive control method according to the present invention, when the pulse signal for ejecting ink is supplied to the ink jet recording head, the first to nth divisions are made in the scanning direction of the recording head. Of the recording areas, the temperature of the recording head is detected before scanning the first recording area, and the pulse condition of the pulse signal in the first recording area is set based on the detected temperature for recording. The pulse conditions are stored while the pulse conditions are set, and the total number of recording dots ejected in the first recording area is counted. It is characterized in that the pulse condition of the pulse signal supplied to the recording head is set based on the total number of recording dots.

[0015]

According to the present invention, ink is ejected under the pulse condition set based on the detected temperature of the print head in the first print area of scanning, but in the print areas immediately thereafter, the ink is ejected in the print area immediately before that. From the total number of recorded dots and the pulse condition, the temperature rise caused by recording in the immediately preceding recording area is expected, and the pulse condition for driving is determined in that temperature state. It is possible to accurately control the ink discharge volume without depending on the temperature distribution and the variation in the temperature rising characteristic of each print head.

[0016]

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

(Embodiment 1) FIG. 1 shows an outline of an ink jet recording head to which the present invention can be applied. Where 10
Is a recording head, 11 is an ink ejection surface of the recording head 10,
Reference numeral 12 denotes a plurality of ink ejection openings arranged on the ink ejection surface 11, 13 denotes a liquid passage communicating with each ink ejection opening 12, 1
Reference numeral 4 denotes a common liquid chamber that supplies ink to each ink ejection port 12 through the liquid passage 13, and reference numeral 15 denotes an electrothermal conversion element (heater) arranged in each liquid passage 13. It should be noted that each heater 15 is provided with an electrode 16 for energization and the heater 1
Temperature detecting means 17 formed of the same material as the electrode 16 (for example, an aluminum film) is provided at both ends of the region where the electrode 5 is provided.

These temperature detecting means 17 are arranged on the substrate 18 together with the electrode 16 and the heater 15, and the substrate 1
8 shows a positive resistance change as the temperature rises by driving the heater 15 above. In addition to the above, the temperature detecting means 17 may be one in which a diode is formed at a similar position, and by passing a current through the temperature detecting means 17, it is possible to detect the temperature in the vicinity thereof by a voltage change. Further, the recording head 10 has 64 nozzles arranged at a density of 360 per inch, and approximately 80 ng of ink is ejected from each ink ejection port 12 at one time.

FIG. 2 shows a structural example of an ink jet recording apparatus to which the present invention can be applied. Here, 21 is an ink tank for supplying ink to the recording head 10, 22 is an ink tank 21 mounted together with the recording head 10, and a carriage that moves along guide shafts 23A and 23B at a predetermined timing by a driving means (not shown). , 24 are flexible cables for sending recording signals to the recording head 10. Reference numeral 25 is a platen for holding a recording sheet 26, which is a recording medium, at a position facing the ink ejection surface 11 of the recording head 10, 27 is a cap unit of a recovery means disposed at a position opposed to the ink ejection surface outside the recording region, 28 Is a cap that covers the ink ejection surface 11, and 29 is a cleaning blade that wipes the ink ejection surface 11.

In the ink jet recording apparatus constructed as described above, the ink ejection operation from the ink ejection port 11 of the recording head 10 is controlled by the control device according to the present invention as will be described later, and at the same time for each line of recording. Sheet feeding is performed by a sheet feeding unit (not shown), and a recording image with ink dots is formed on the recording sheet 26.

FIG. 3 shows the configuration of the control circuit of the ink jet recording apparatus. Here, reference numeral 30 denotes a system controller for controlling the entire apparatus, which functions as a CPU and stores a control program.
R used during processing operations related to OM30A and control
It is equipped with AM30B. Reference numeral 31 is a carriage driving motor, and 32 is a motor involved in feeding and carrying the recording sheet 26. In contrast to these motors 31 and 32, 31A and 32A are drivers for the motors 31 and 32. Thus, the conditions for driving the motors 31 and 32 are supplied to the drivers 31A and 32A from the system controller 30 as signals, and the motors 31 and 32 are driven according to the conditions.

Reference numeral 33 is a host computer, and 34 is a buffer for temporarily storing data and information relating to recording from the host computer 33. In the buffer 34, the information is temporarily stored until the system controller 30 reads the information. To store. Reference numeral 35 denotes a frame buffer memory, which develops the recording data read by the system controller 30 into image data. Therefore, the frame buffer memory 35 has a memory size for recording.

A recording control unit 36 controls the recording head 10 in accordance with a command from the system controller 30 as will be described later. The recording control unit 36 can control the ink ejection speed and the number of recording data. At the same time, the pulse condition of the signal given to the recording head 10 for ejecting ink is determined. Reference numeral 37 denotes a storage element in which the data to be printed is temporarily stored each time printing is performed, and the storage capacity of the storage element also varies depending on the number of nozzles of the print head 10. Reference numeral 38 is a driver for driving the recording head 10. The driver 38 is a recording control unit 36.
The recording head is driven in accordance with the control signal from.

FIG. 4 shows a circuit configuration for the recording control unit 36 to calculate a pulse condition given for driving the recording head 10 via the driver 38. That is, in the present embodiment, as described above, the scanning width of the recording head 10 is set to n.
First, the temperature detecting means 1 is divided into recording areas (blocks), and first, before recording by the first block (i = 1) is started.
The pulse condition is set as will be described later based on the detected temperature detected by No. 7 (see FIG. 1), and the number of recording dots by the first block is counted, and the following blocks (2 ≦ i ≦ n ), A new pulse condition is set on the basis of the dot number and pulse condition counted in the immediately preceding block, and recording is successively performed.

4, 41 is a counter for counting the total number of recording dots in the i-th block stored in the recording element 37 shown in FIG. 3, and 42 is the temperature detecting means 1.
A pulse condition setting circuit for setting a pulse condition from the detected temperature from 7 and the dot count value from the counter 41;
A pulse condition storage circuit 43 temporarily stores the pulse condition set in the pulse condition setting circuit 42 for the next block driving. Therefore, in the recording control unit 36 configured as described above, only the pulse condition for recording the first block is determined by the detection result of the temperature detecting means 17 provided in the recording head 10, but the second condition is determined. The pulse condition for recording the i-th (2 ≦ i ≦ n) block is the total number of recording dots of the i-th block and the (i−1) -th block stored in the pulse condition storage circuit 43. And the pulse conditions of. That is, as for the temperature used for determining the pulse condition, the temperature detected at the beginning of the scanning is used as it is during the scanning. More specifically, according to the present invention, the recording head 10 by the temperature detecting means 17 is used.
The temperature is detected only before the scanning of the recording head 10 and is not performed during the scanning, that is, during the recording. This is because the change in the temperature distribution in the print head 10 before scanning is so small that it can be ignored as compared with the change in the temperature distribution during printing, and therefore the temperature of the print head can be accurately detected only before scanning. is there.

The reason why the (i-1) th pulse condition is applied to the i-th block drive is clear if the opposite case is assumed. For example, assuming that the pulse condition is set based on the number of the recording dots up to the (i-2) th, two cases are assumed, where the actual temperature at that time is 30 ° C and 40 ° C. In both cases, the same pulse width may be calculated if the number of (i-1) th print dots is the same, and the pulse width does not correspond to the temperature of both, and as a result, the desired ejection is performed. This is because the volume cannot be obtained. That is, the (i-1) th drive pulse condition represents the heat storage state of the recording head up to the (i-1) th block.

It is also possible to detect the temperature before scanning, determine the pulse width, and further integrate the number of recording dots in each block to calculate and correct the pulse width. In this case, only the number of recording dots is required. Since the correction is performed from the above, even if the number of print dots is the same as the block progresses, a calculation error is likely to occur when a difference in temperature rise due to a difference in print pattern occurs.

As described above, according to the present embodiment, the immediately preceding recording state is changed from the first (i-1) th recording dot number to the (i-1) th temperature state from the start of scanning. By knowing each from the (i-1) th pulse width, the i-th pulse condition is determined, so that the ejection volume can always be made constant.

FIG. 5 shows a plurality of heaters 15 of the recording head 10.
An example of the pulse waveform given to the is shown. Here, two rectangular wave pulses are applied for each ink ejection. In the case of this embodiment, the pulses P ₂ and P ₃ are set so as to maintain a constant pulse width, and each pulse is 4 μm.
sec, 8.5 μsec. The pulse P ₁ is variable, and by changing the width of the pulse P ₁ , it is possible to suppress fluctuations in the ink ejection amount when the temperature of the recording head 10 rises. Specifically, the width of the pulse P ₁ is shortened when the temperature of the recording head 10 rises, and conversely, the width of the pulse P ₁ is lengthened when the temperature of the recording head 10 falls.

FIG. 6 shows the pulse conditions applied to the recording head 10 during recording by the first block according to the temperature of the recording head 10 detected by the temperature detecting means 17 before the scanning of the recording head 10. Is a table shown,
The width of the pulse P ₁ in FIG. 5 is set according to the temperature of the recording head 10.

FIG. 7 shows the total recording dot number N of the image data corresponding to the i-th block and the pulse condition (width of P ₁ ) given during recording in the (i-1) th block. From that, the table for setting the pulse condition to be given at the time of recording in the i-th block is shown. In the case of the present embodiment, the upper limit recordable dot number corresponding to one block is 64 × 270 = 1728.
It is set to 0 dots.

FIG. 8 shows how the pulse conditions change when an image is recorded. If the temperature detected by the print head 10 before the start of scanning is 28 ° C., the pulse condition given to the first block is P ₁ (1) = 1.5 μsec from the table shown in FIG. Therefore,
Recording of this condition in the source block 1 is performed. Then, when the total number of recorded dots in the block 1 is 13200 dots, the pulse condition in the block 2 is P from FIG.
₁ (2) = 1.35 μsec, and recording in block 2 is performed under this condition. Further, as shown in FIG. 8, since the total number of recorded dots in block 2 is 7000 dots, pulse condition P ₃ (3) = 1.20 μm in block 3
It becomes sec. The same processing is performed thereafter, and the pulse conditions P ₁ (i) in blocks 1 to 5 have the values shown in FIG.

As described above, the pulse condition of the block to be recorded is determined from the total number of recorded dots in the previous block and the pulse condition when the previous block is recorded. When the recording head 10 was driven at a discharge frequency of 6 kHz to record various patterns, a high-quality image without density unevenness could be obtained.

(Embodiment 2) FIG. 10A shows an outline of a recording head applied to the second embodiment. In the recording head 100 according to this example, an ink ejection port group 120Y that ejects yellow ink, an ink ejection port group 120M that ejects magenta ink, an ink ejection port group 120C that ejects cyan ink, and black ink are ejected on the ink ejection surface 110. The ink ejection port group 120B is provided in this order. In addition,
The ejection port groups of these colors are configured so as not to overlap with each other in the scanning direction, and spaces S1, S2, S3 are provided between the ink ejection port groups of the respective colors. The ink ejection port groups 120Y, 12
There are 24 ink ejection ports at 0M and 120C,
Further, the ink ejection port group 120B has 48 ink ejection ports each having a density of 360 per inch (360 dp).
i). In addition, the ink ejection port group 120B
Discharge amount is about 80 ng per discharge port, ink discharge port group 1
The discharge amount at 20Y, 120M, and 120C is about 40 ng per discharge port.

FIG. 10B shows an outline of the nozzle arrangement on the substrate (heater board) 180 of the recording head 100. As shown in this figure, between the ejection port group 120C and the ejection port group 120B. A sensor 170 is provided as a temperature detecting unit of the recording head 100. As the recording apparatus in which the recording head 100 shown in FIGS. 10A and 10B can be mounted, the same recording apparatus as shown in FIG. 2 can be used.

Next, the recording procedure for recording an image as shown in FIG. 11G using the recording head 100 shown in FIGS. 10A and 10B will be described with reference to FIGS. It will be described according to G). Here, when recording a black image, the first to 24th ink ejection ports counted from the top in FIG. 10A are used in the ejection port group 120B for ejecting black ink.

First, as shown in FIG. 11A, the upper half of the black character "B" is scanned and recorded using the first to 24th ink ejection ports. Subsequently, the recording sheet is fed by the 24 ejection ports, and the lower half of the black character "B" is scanned and recorded using the same ink ejection port as shown in FIG. 11B. At the same time as the scanning at this time, cyan ink is ejected from the cyan ink ejection port group 120C and a part of the cyan background portion is recorded. Then, after further feeding the recording sheet by 24 ejection ports,
As shown in FIG. 11C, a part of the cyan background portion is scanned and recorded. Note that background portions of other colors are not recorded during this scanning. After that, after further feeding the recording sheet by 24 ejection ports, as shown in FIG. 11D, the remaining portion of the cyan background portion is printed and at the same time a portion of the magenta background portion is printed. Similarly, FIG. 11 (E)-
As shown in (G), the remaining portions of the magenta background portion and the yellow background portion are recorded.

When the recorded image is only a black image,
Since all 64 ink ejection ports of the ejection port group 120B for ejecting black ink are used, as described above, the recording head 100 used in this embodiment records only a black image and records a color image. The feeding amount of the recording sheet is different depending on the case, and the ink ejection port group used for recording a color image is composed of a total of 96 ink ejection ports of 24 ink ejection ports for each of the four colors. When recording only a black image, 64 ink ejection openings are used. Therefore, in the present embodiment, the tables for setting the pulse conditions are made different when recording a black image and when recording a color image.

FIGS. 12A and 12B show the total recording dot number N of the image data corresponding to the i-th block and the pulse conditions applied when recording the (i-1) -th block. 12A shows a table for setting a pulse condition to be applied when the i-th block is recorded. FIG. 12A shows a color image recording table, and FIG. 12B shows a black image. It is a table for recording.

When recording a color image, 1
The number of recordable dots corresponding to each block is set to 24 × 4 × 300 = 28800 dots. When recording a black image, the number of recordable dots corresponding to one block is 64 × 300 = 1920.
It is set to 0 dots. Further, the temperature detection of the recording head 100 before the scanning by the recording head 100 and the setting of the pulse condition in the first block according to the detected temperature are the same as the procedure described in the first embodiment, and the description thereof will be omitted. To do.

As described above, the recording head 10
When 0 was driven at an ejection frequency of 5.4 kHz and recording was performed, a desired color image without color unevenness could be obtained.

(Other Embodiments) The upper limit of the number of dots for recording corresponding to one block is not limited to the numerical values described in Embodiments 1 and 2, and the ejection frequency and the recording head It is appropriately set according to the size (the number of nozzles). For example, in Example 1, 1
The number of dots corresponding to one block is 64 × 150 = 96
If it is set to 00 dots, more precise control becomes possible.

Further, in the table for recording a color image in the second embodiment, the total number of recorded dots for 24 ink ejection ports for each of yellow, magenta, cyan and black, and a total of 96 ink ejection ports is counted. Then, the pulse conditions for each color were recorded under the same conditions, but a separate table was provided for each color, and the pulse conditions were recorded under the same conditions for each color, but a separate table was provided for each color. If the pulse conditions are individually determined, it is possible to control with higher accuracy. For example, in this case, the upper limit number of recording dots per block for each color may be set to 24 × 300 = 7200 dots. Further, the pulse applied to the recording head is not limited to the form in which the width of the pulse P ₁ is changed as shown in FIG. 5, and may be in any form as long as the change in the ejection amount can be controlled. For example, the width of the pulse P ₁ may be kept constant and the width of the pulse P ₂ may be changed, or all of the pulses P ₁ , P ₂ and P ₃ may be changed. Good.

It should be noted that the present invention is provided with a means (for example, an electrothermal converter or a laser beam) for generating heat energy as energy used for ejecting ink, particularly in the ink jet recording system, and The effect is excellent in a recording head and a recording apparatus of a system that causes a change in ink state by energy. This is because such a system can achieve high density recording and high definition recording.

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 is a so-called on-demand type,
It can be applied to any of the continuous type, but especially 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 recording information and giving a rapid temperature rise exceeding nucleate boiling, heat energy is generated in the electrothermal converter, and film boiling is caused on the heat acting surface of the recording head. Liquid (ink) corresponding to this drive signal in a one-to-one correspondence
It is effective because bubbles can be formed inside. 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.

As the constitution of the recording head, in addition to the combination constitution of the discharge port, the liquid passage, and the electrothermal converter (the linear liquid passage or the right-angle liquid passage) as disclosed in the above-mentioned specifications, US Pat. No. 4,558,333, US Pat. No. 4,558,333, which discloses a configuration in which a heat acting portion is arranged in a bending region.
The structure using the specification of No. 59600 is also included in the present invention. In addition, Japanese Unexamined Patent Publication No. 59-123670 discloses a configuration in which a common slit is used as a discharge portion of the electrothermal converter for a plurality of electrothermal converters, and an opening for absorbing a pressure wave of thermal energy is provided. The effect of the present invention is effective even if the configuration corresponding to the ejection portion is disclosed in JP-A-59-138461. That is, according to the present invention, recording can be surely and efficiently performed regardless of the form of the recording head.

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 or 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, as the constitution of the recording apparatus of the present invention, it is preferable to add the ejection recovery means of the recording head, the preliminary auxiliary means and the like because the effects of the present invention can be further stabilized. Specifically, heating is performed by using a capping unit, a cleaning unit, a pressure or suction unit for the recording head, an electrothermal converter or a heating element other than this, or a combination thereof. Examples thereof include a preliminary heating unit for performing the discharge and a preliminary discharge unit for performing discharge different from the recording.

In addition, in the above-described embodiments of the present invention, the ink is described as a liquid, but an ink that solidifies at room temperature or lower and that softens or liquefies at room temperature may be used. Or, in the inkjet system, it is common to control the temperature of the ink itself within the range of 30 ° C. or higher and 70 ° C. or lower to control the temperature so that the viscosity of the ink is within the stable ejection range. Sometimes, a liquid ink may be used. In addition, the temperature rise 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 in order to prevent the evaporation of the ink, it is solidified and heated in the standing state. You may use the ink liquefied by. In any case, by applying thermal energy such as ink that is liquefied by applying thermal energy according to the recording signal and liquid ink is ejected, or that begins to solidify when it reaches the recording medium. The present invention can be applied to the case where an ink having a property of being liquefied for the first time is used. In this case, the ink is
JP-A-54-56847 or JP-A-60-7
As described in Japanese Patent No. 1260, it may be configured to face the electrothermal converter in a state of being held as a liquid or a solid in the concave portion or the through hole of the porous sheet. 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 the form of the ink jet recording apparatus to which the present invention is applied, other than the one used as an image output terminal of information processing equipment such as a computer,
It may be a copying machine combined with a reader or the like, or may be a facsimile machine having a transmitting / receiving function.

[0051]

As described above, according to the drive control apparatus for the ink jet recording head of the present invention, the pulse condition setting means for setting the pulse condition of the pulse signal supplied to the recording head and the pulse condition are set. Pulse condition storage means for storing, counting means for counting the number of dots recorded in each of the first to nth recording areas divided in the scanning direction of the recording head, and temperature detection for detecting the temperature of the recording head. Means for setting the pulse condition in the first recording area based on the temperature detected by the temperature detecting means before the scanning of the first recording area by the pulse condition setting means, Since the pulse condition in the n-th recording area is controlled so as to be set based on the pulse condition set in the immediately preceding recording area and the number of dots, the pulse condition is always set to each ink ejection port. It is possible to discharge volume constant.

Further, according to the drive control method of the ink jet recording head according to the present invention, the first recording area is scanned before scanning the first recording area among the first to nth recording areas divided in the scanning direction of the recording head. The temperature of the recording head is detected, the pulse condition of the pulse signal in the first recording area is set based on the detected temperature, recording is performed, the pulse condition is stored, and then the first recording is performed. The total number of recording dots ejected in the area is counted, and in the second and subsequent recording areas, the pulse signal supplied to the recording head based on the pulse condition set in the recording area immediately before and the total number of the recording dots ejected. The pulse condition for driving can be set in a state where the temperature condition of the recording head is always taken into consideration.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing a configuration of an inkjet recording head applicable to a first embodiment of the present invention.

FIG. 2 is a perspective view showing the outer appearance of an inkjet recording apparatus applicable to the first embodiment.

FIG. 3 is a block diagram of a control circuit of the inkjet recording apparatus according to the present invention.

FIG. 4 is a block diagram showing a circuit configuration for determining a pulse condition according to the present invention.

FIG. 5 is a waveform diagram of a pulse signal of the recording head provided in the first embodiment.

FIG. 6 is a table showing pulse conditions corresponding to the temperature of the recording head in the first embodiment.

FIG. 7 is a table diagram for setting pulse conditions of the recording head in the first embodiment.

FIG. 8 is a diagram showing an example of the number of dots for each recording area when recording is performed in the first embodiment.

FIG. 9 is a diagram showing an example of pulse conditions for each recording area in the first embodiment.

FIG. 10 is an explanatory view showing an outline of a color ink jet recording head applicable to the second embodiment with a perspective view (A) and a plan view (B).

FIG. 11 is an explanatory diagram showing processes of recording a color image using the recording head of Example 2 with (A) to (G).

FIG. 12 is a diagram showing tables (A) and (B) for setting the pulse conditions of the recording head in the second embodiment.

[Explanation of symbols]

10 Recording Head 11 Ink Ejection Port Surface 12 Ink Ejection Port 13 Liquid Path 15 Electrothermal Conversion Element (Heater) 17 Temperature Detection Unit 21 Ink Tank 22 Carriage 26 Recording Sheet 30 System Controller 31, 32 Motor 36 Recording Control Section 37 Recording Element 41 Counter 42 Pulse condition setting circuit 43 Pulse condition storage circuit 120Y, 120M, 120C, 120B Ink ejection port group

Claims (8)

[Claims] 1. A pulse condition setting means for setting a pulse condition of a pulse signal supplied to a recording head, a pulse condition storing means for storing the pulse condition, and a first to a first division divided in a scanning direction of the recording head. Before scanning the first recording area by the pulse condition setting means, a counting means for counting the number of dots recorded for each nth recording area and a temperature detecting means for detecting the temperature of the recording head are provided. The pulse condition in the first recording area is set based on the temperature detected by the temperature detecting means,
A drive control device for an inkjet recording head, wherein the pulse condition in the nth recording area is controlled to be set based on the pulse condition set in the recording area immediately before and the number of dots. 2. The ink jet recording head according to claim 1, wherein the recording head is provided with an ink ejection port for ejecting ink according to the pulse signal in a direction substantially orthogonal to the scanning direction. Drive controller. 3. The recording head has a plurality of ink ejection port groups for ejecting ink of different colors or gradations in a direction substantially orthogonal to the scanning direction, and the ink ejection port groups are individually generated by the pulse signal. The drive control device for an ink jet recording head according to claim 1, wherein the drive control device is driven by the following. 4. The electro-thermal conversion element for generating heat energy for causing film boiling in the ink, as an element for generating energy for ejecting the ink, in the recording head. 4. The drive control device for an inkjet recording head according to any one of items 1 to 3. 5. When supplying a pulse signal for ejecting ink to an ink jet recording head, a scan of a first recording area among first to nth recording areas divided in a scanning direction of the recording head. The temperature of the recording head is previously detected, the pulse condition of the pulse signal in the first recording area is set based on the detected temperature, recording is performed, and the pulse condition is stored, and then the first condition is stored. The total number of recording dots ejected in one recording area is counted, and in the second and subsequent recording areas, the recording condition is supplied to the recording head based on the pulse condition set in the recording area immediately before and the total number of recording dots ejected. A drive control method for an inkjet recording head, characterized in that pulse conditions of a pulse signal to be set are set. 6. The ink jet recording head according to claim 5, wherein the recording head is provided with an ink ejection port for ejecting ink according to the pulse signal in a direction substantially orthogonal to the scanning direction. Drive control method. 7. The recording head has a plurality of ink ejection port groups for ejecting inks of different colors or gradations in a direction substantially orthogonal to the scanning direction, and the ink ejection port groups are individually generated by the pulse signal. The driving control method for an inkjet recording head according to claim 5, further comprising: 8. The recording head has an electrothermal conversion element that generates thermal energy that causes film boiling in the ink, as an element that generates energy for ejecting the ink. 8. The drive control method for an inkjet recording head according to any one of items 1 to 7.