JPH05338199A - Ink jet recording apparatus - Google Patents

Abstract

PURPOSE:To detect the non-jet of ink in an ink jet recording head to rapidly take a measure to meet this situation. CONSTITUTION:The specified test pattern recorded on recording paper 201 by a recording head 202 is read by a light emitting diode 207 and a phototransistor 206 and the non-jet from the emitting orifice of the recording head can be detected on the basis of the test pattern.

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 a structure for coping with ink ejection failure caused by clogging of an ink jet recording head.

[0002]

2. Description of the Related Art In a recording head used in an ink jet recording apparatus, clogging of a discharge port or the like due to thickening of ink is a greater problem than ever before.

In general, an ink jet type recording head is provided with an ejection port for ejecting ink and an ink path communicating with the ejection port, and by supplying energy to the ink in the ink path, the ink is ejected from the ejection port. Target. Such ejection openings and ink passages in the recording head are relatively small, and therefore the effect of the effect of ink viscosity on them is relatively large. Further, since the ink existing in the vicinity of the ejection port is in direct contact with the atmosphere, the evaporation of ink moisture is easily promoted, and the ink in the ejection port and the ink passage is relatively thickened. When such ink thickening occurs in the ejection port or the like, ejection failure such as deflection of the ejection direction or decrease in ejection amount occurs, or when the degree of thickening is remarkable, the ejection port or the like is thickened. Ink ejection may occur due to so-called clogging that is blocked by ink.

Various configurations have been conventionally known for coping with ejection defects and the like due to the increase in ink viscosity as described above. The main ones of these are so-called ejection recovery processes, which include idle ejection that ejects ink that is not involved in recording, and suction that ejects ink from the ejection port and the like to the outside of the recording head. There is processing etc. In addition, as a structure for preventing thickening of the ink, so-called capping is known, which covers the portion of the recording head where the ejection port is provided in order to suppress the evaporation of ink moisture and shuts off the ejection port from the atmosphere. There is.

[0005]

However, even if the above-described ejection recovery processing and capping are appropriately performed, ejection failure cannot be completely prevented.

For example, depending on the user who uses the ink jet recording apparatus, there are cases where the apparatus is not used for a period of up to one year. In such a case, the degree of thickening of the ink is extremely remarkable even if capping is performed, and the eye is very thick. It will cause a blockage. Then, such clogging is not eliminated by the suction process after the use of the apparatus is restarted, and the ink is not ejected. Further, even if it is not such an extreme example, there may be a case where ejection is not possible depending on the operating conditions of the apparatus such as the temperature and humidity of the atmosphere, and only some ejection ports are provided according to the print data. It may not be ejected.

When the ejection failure occurs in this way, this ejection failure is almost always detected by actual recording and the operator or the like recognizing a defect in the recording result. Therefore, for example, in a continuous recording or a recording in a facsimile, in which the operator does not monitor for a relatively long time, a large number of recording results may be output in which a defect due to ejection failure occurs.

Further, when the ejection failure once occurs and the degree of the ejection failure is large, the ejection processing may not be restored to a good ejection state by the above-described recovery processing. In such a case, the recording head must be replaced. Become.

The present invention has been made in order to solve the above-mentioned conventional problems, and an object of the present invention is to detect non-ejection in a recording head and quickly deal with it. An object of the present invention is to provide an ink jet recording apparatus capable of continuing recording by using the recording head even when irreversible serious ejection failure occurs.

[0010]

In an ink jet recording apparatus for ejecting ink to a recording medium to perform recording, a recording head for ejecting ink and a test pattern on the recording medium by the recording head. It is characterized by comprising a test pattern recording means for recording and a non-ejection detecting means for detecting non-ejection of ink of the recording head from the test pattern on the recording medium.

Further, in an ink jet recording apparatus for ejecting ink to a recording medium for recording, a recording head having a plurality of ejection ports and ejecting ink from the plurality of ejection ports, Corresponding to each of the plurality of ejection openings in the recording head, based on drive data supply means for supplying drive data for ejecting ink from the ejection openings, and drive data supplied from the drive data supply means, When the head drive unit for ejecting ink from each of the plurality of ejection ports and ink non-ejection occurs in a part of the plurality of ejection ports, the drive data supply unit supplies the drive data to the non-ejection unit. Data supply control means for changing according to the ejection port other than the ejection port that is causing,
It is characterized by having.

[0012]

With the above arrangement, it is possible to read specific information from the test pattern when ejection failure has occurred in the print head, and it is possible to detect ejection failure in a portion of the information.

Even when ejection failure occurs in a part of the ejection openings of the recording head, the drive data can be made to correspond to another normal ejection opening. It is also possible to perform recording by using the recording head in which the occurrence of the error occurs.

[0014]

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

(Embodiment 1) FIG. 1 is a schematic perspective view showing an ink jet recording apparatus according to an embodiment of the present invention.

In FIG. 1, the recording head 202 is arranged with its plurality of ejection openings (not shown) facing the lower side of the apparatus.
An ink tank 213 is attached to the recording head 202,
The ink stored in the recording head 202 is supplied to the recording head 202 via the ink supply tube 213A in response to the ink ejection from the recording head 202. A part of the belt 210 stretched by pulleys 205 and 205B is attached to a part of the recording head 202. The belt 210 moves by the rotation of the pulley 205A caused by the driving force of the motor 205. As a result, the recording head 202 moves the belt 2
Movement in the direction in which 10 extends (hereinafter also referred to as main scanning)
With this movement, ink is ejected from the ejection port and recording is performed on the recording paper 201 as shown in the figure. It should be noted that illustration of other mechanisms relating to the movement and support of the recording head, such as a guide shaft for guiding the movement of the recording head 202, is omitted.

A pair of conveying rollers 211 extending in the moving direction of the recording head 202 holds the recording paper 201, and one of the conveying rollers 211 is driven by a motor 203 to rotate to convey the recording paper 201. This recording paper 2
The conveyance path 01 is formed by a pair of pinch rollers 212 in addition to the conveyance roller 211 and a paper discharge roller (not shown) arranged on the downstream side of the recording area of the recording head 202.

The photo sensor 204 is provided at a position where it can be engaged with one end of the conveyed recording paper 201 in the width direction, and thereby the front end of the recording paper 201 can be detected.

The pair of phototransistor 206 and light emitting diode 207 form part of a test pattern reading system according to one embodiment of the present invention. That is, the phototransistor 206 and the light emitting diode 2
Reference numeral 07 denotes recording paper 201 in the inkjet device of this example.
The test pattern recorded on the one end of the recording paper 201 can be read by being provided at a portion corresponding to one end in the width direction of the recording paper 201.

FIG. 2 is a block diagram showing the control arrangement of the ink jet recording apparatus shown in FIG.

In FIG. 2, the main control unit 103 executes control processing and data processing relating to the operation of each unit of the apparatus, and mainly, the CPU 106, the processing procedure of the CPU 106 and the ROM 104 storing test pattern data described later, and the recording. It has a bitmap memory 105 that stores dot data that forms power characters, images, and the like.

Text data 121 consisting of a series of character codes sent from the host computer is stored in the input buffer 102 via the input control unit 101. The main control unit 103 sequentially refers to the character pattern generation unit 107 by a series of character codes of the sentence data stored in the input buffer 102 and reads a character pattern corresponding to the character code. The character pattern is a dot pattern formed of the characters, and the read character pattern is stored in the memory 105. When the main control unit 103 develops a predetermined amount of character patterns in the bitmap memory 105, the main control unit 103 stores the first drive data for driving the recording head 202 according to the character patterns in the drive data buffer 108.

The drive data buffer 108 has a so-called double buffer structure, and the content of one of the buffers is read out for driving the print head and sent to the print unit 110 via the print head control unit 109. While driving, the main controller 103 stores the next drive data in the other. This can increase the recording speed. Further, the two buffers forming the drive data buffer 108 each have a capacity that is the square of the number of ejection ports included in the recording head. For example, if the number of ejection openings of the print head is 32, the procedure for each buffer is 32 × 32 bits.
Becomes

FIG. 3 is a circuit diagram showing details of one buffer in the drive data buffer 108.

The 32-bit dot data 122 sent from the main control unit 103 corresponds to the synchronous clock 123.
First, the flip-flop of the first row shown in FIG.
Abbreviated as F). The next dot data sent from the main control unit 103 is loaded in the first row in accordance with the synchronous clock 123 sent together with it, and the data already loaded in the first row is loaded in the second row. It When the above operation is sequentially repeated 32 times, 32 × 32 bit dot data is stored in this buffer.

FIG. 4 is a schematic diagram showing the relationship between the moving direction of the recording head and its ejection port arrangement and the data arrangement (32 rows, 32 digits) in the data buffer shown in FIG.

Discharge port 202N in recording head 202
Array corresponds to the data array in each digit of the data buffer, and the corresponding digit changes as the print head 202 moves. Therefore, the data is sequentially read from the data buffer 108 as the recording head moves.

That is, the 32-bit data of each digit in the buffer shown in FIG. 3 is input to the selector 401. The selector 401 is a selector for selecting only one digit from the 32 digits, and the counter 4
One digit is selected based on the select data of ⁵ bits (2 ⁵ = 32 from 02. This causes the drive data buffer 108 to select 32 bits corresponding to each ejection port 202N.
The drive data of t is read. The counter 402 is 5b
It is a counter composed of it, and sequentially counts up the pulse 124 input to its clock input. The read control unit 111 also supplies the pulse 124 to the drive data buffer 108 according to the movement of the recording head 202. As a result, the drive data 125 is read according to the movement of the recording head 202. That is, the read control unit 111 moves the recording head by sending the drive data 125 to the recording head control unit 109 by supplying the pulse 124 and by sending the pulse 128 to the motor 205 for moving the recording head 202.

Further, the main control section 103 outputs a rotation command signal 126 to the motor 203 in the recording section 110,
The recording paper 201 is conveyed. The motor 203 is a so-called stepping motor, and has a rotation command signal 126.
When the recording paper 201 is conveyed by one dot constituting a character or the like and the leading end of the recording paper 201 reaches the position of the recording paper sensor 204, the recording paper is conveyed by one step corresponding to one pulse of The sensor 204 outputs a pulse 127 to the read control unit 111.

When the read control unit 111 finishes the reading of the negative buffer in the drive data buffer 108, the read control unit 111 switches the buffer to be read to the other buffer in the drive data buffer 108, and the next drive data. Is output to the main control unit 103, and a signal 129 requesting that it be loaded into the drive data buffer 108 is output. The main controller 103 receives this signal 129 and sends the next drive data to the drive data buffer 108. In this way, recording for one page is performed.

5A and 5B are a front view and a sectional view showing details of the recording head 202, respectively.

The recording head 0202 has 32 ejection ports 20.
Ink paths 351-1 to 35-1 to 35 corresponding to 2N, respectively.
51-32, and electrothermal converters H1 to H32 for generating thermal energy are arranged in the respective ink paths. These electrothermal converters H1 to H32 generate heat when a drive signal from the recording head controller 109 is applied.

As shown in FIG. 6A, before the ink is ejected, the ink passages 351-of the recording head 202 are formed.
At n, a meniscus is formed in the vicinity of the ejection port 202N due to a capillary force or the like to fill the ink path with ink. Here, when the drive signal is applied to the electrothermal converter Hn, as shown in FIG. 6B, a bubble is rapidly expanded in the ink, which causes the ejection port 202N toward the recording paper. Ink is ejected. After that, the bubbles contract and return to the original state as shown in FIG.

The ejection operation as described above is performed by the recording head controller 109 in accordance with the above-mentioned drive data 125 sent from the drive data buffer 108.
When this drive data is "1", a drive signal is applied and ejection is performed.

A process for checking the ejection failure of the recording head in the above-mentioned structure will be described below.

In FIG. 2, for example, when the operator gives an instruction to record a test pattern via the operation / display panel 112, the main control section 103 receives this and reads the drive data for recording the test pattern from the ROM 104, The data is expanded in the drive data buffer 108. As a result, the recording operation described above is performed, and the test pattern shown in FIG. 7 is recorded. In this test pattern, black squares 601-6
32 is recorded by ink ejection from one ejection port of the recording head. For example, the black square 601 is recorded by the first ejection port in the ejection port array, and the black square 602 is recorded by the second ejection port. Each black square is recorded with a predetermined length in each of the main operation direction and the paper feed direction by repeating the main operation of the recording head 202 and the predetermined paper feed of the recording paper 201. That is, in normal printing other than the test pattern, 32 lines corresponding to these are used to print 32 lines at a time, but one black square in the test pattern is one discharge. It is formed by sequentially recording line by line using the exit.

This black square pattern recorded on the recording paper 201 passes through the optical path formed by the light emitting diode 207 and the phototransistor 206 shown in FIG. As a result, the phototransistor 206 outputs a signal of "1" level when receiving the reflected light of the white portion of the recording paper 201, and hardly receives the reflected light when there is a black square portion in the optical path. , "0" level is output.

Therefore, when the test pattern shown in FIG. 7 is printed by a normal print head having no ejection failure, the phototransistor 206 as shown in FIG.
The output signal from is obtained. However, the recording head 20
When ejection failure occurs in part of the second ejection ports, the output from the phototransistor 206 has a pattern as shown in FIG. 8B, for example. In this case, it indicates that ejection failure has occurred at the fourth ejection port.

The main control unit 103 includes the phototransistor 2
If there is an ejection port that has caused ejection failure by performing ejection failure detection processing based on the output signal 130 from 06, the fact is notified to the host computer (not shown) and displayed on the operation / display panel 112. Simultaneously with these processes, suction (the device configuration for this operation is omitted in FIGS. 1 and 2) is performed.

Hereinafter, the non-ejection detecting process by the main control unit 103 will be described with reference to the flowchart shown in FIG.

Signal 13 from phototransistor 206
0 indicates that the reflection information from the recording paper 201 is sequentially output as the recording paper 201 is conveyed. Therefore, in the non-ejection detection process, the non-ejection is detected by sequentially checking the signal 130 shown in FIG. 8 in the output order from the left side of the drawing.

First, in step S101, the recording paper 2
When the white portion at the tip of 01 is conveyed into the optical path and it is determined that the signal 130 is at "1" level, the time when the signal 130 is at "1" level is measured in step S102. This measurement continues until it is determined in step S103 that the signal 130 is at "1" level. During this time, "1" for a period of time the level is longer than the first time t ₁ corresponding to up to the black squares of a recording sheet edge step S11
If it is determined in step 4, it is determined that an error has occurred and processing to that effect is performed.

In step S103, the signal 130 is "0".
If it is determined that the level is the level, the time during which the signal 130 is at the "1" level is determined to be the predetermined time t in step S104.
It is judged whether or not it is ₁ , and if the judgment is negative, error processing is performed. In the case of affirmative determination, the parameter n relating to the number of ejection ports is set to 1 in step S105, and step S106
Then, the time when the signal 130 is at the “0” level is measured.
This measurement is similarly performed until the signal 130 is determined to be at the "1" level in step S107. Further, during this period, the time during which the signal 130 is at “0” level is the predetermined time t.
If it is determined in step S115 that it is ₂ or more,
Perform error handling.

When it is determined in step S107 that the signal 130 is at "1" level, in step S108 the time during which the signal 130 is at "0" level is the time t during which the black square of the test pattern is detected. It is judged whether or not it is ₂ , and if the judgment is negative, error processing is performed. In the case of affirmative determination, the time when the signal 130 is at the next "1" level is measured in step S109. Similarly for this measurement,
In step S111 or step S117, the signal 13
It continues until 0 is determined to be the "0" level.

During this measurement, in step S110, it is determined whether or not the parameter n is 32. That is, it is determined whether or not the process is for the last 32nd ejection port of the print head.

If the process is not for the last ejection port,
If it is the process related to the last ejection port, the process proceeds to step S111, and it is determined whether or not the signal 130 is at the "0" level. Until it is judged as "0" level in these steps,
At steps S116 and S119, the time t during which the signal 130 is at the "1" level is detected between the black square and the next black square in the above pattern, respectively.
₃ , or if it is determined that the time from the last black square to the end of the recording paper 201 is longer than the detection time t _4, error processing is performed.

In step S111, the signal 130 is "0".
If it is determined to be level, after the "1" level for a period of time in step S112 it is confirmed to be the time t _3, the contents of the parameter n at step S113 1
Increment and return to the process of step S106. In step S117, the When determining that it is likewise "0" level, "1" level at a time in step S118 is finished the processing procedure and confirm that it is the predetermined time t _3.

FIG. 10 is a waveform diagram for explaining another example of use of the output signal 130 from the phototransistor 206.

When no black square is detected at all as shown in FIG. 10A, or when it is shown that a plurality of ejection openings are continuously non-ejecting as shown in FIG. 10B, Since it is extremely unlikely that a plurality of ejection openings will not eject at the same time, it can be considered that the ink has run out. Therefore, the phototransistor 206 can also be used as an ink out sensor.

When the signal indicating the end of the recording paper is not detected at the time indicated by the arrow in the figure as shown in FIG.
At this point, it is possible to know that the recording paper has jammed. Therefore, the phototransistor 206 can also be used as a jam sensor.

Further, if the non-ejection check is performed by this test pattern when the power is turned on or every predetermined time, it is effective to prevent data loss and image quality deterioration due to non-ejection.

FIG. 11 is a block diagram showing the arrangement of an ink jet recording apparatus according to a modified example of this embodiment.

In FIG. 11, the phototransistor 20
The signal 130 from 6 is input to the counter 183 after the noise component is removed by the waveform shaping circuit 181.
The counter 183 is cleared to 0 in advance by the main control unit 103, and then counts the rising edge of the signal 130 and counts up. Constant generator 185
Is set to "33" in decimal notation.

As shown in FIG. 12, when the signal 130 indicates that no ejection failure has occurred in all ejection ports, the counter 183 is counted up to "33" when all the test patterns have passed. As a result, the output 182 from the comparator 184 becomes the "1" level. The main control unit 103 considers that the recording head is normal when the signal 182 is at the "1" level when passing the test pattern, and the "0" level. If it is left as it is, it can be considered that the ejection failure has occurred in any of the ejection ports.

(Embodiment 2) In this embodiment, when non-ejection is detected, recording will be performed by using ejection ports other than the ejection port in which non-ejection occurred.

In this example, FIG.
The same device as the ink jet recording device described with reference to 2 etc. is used.

FIG. 13 is a schematic diagram showing a test pattern for non-ejection detection according to the second embodiment.

In the test pattern shown in FIG. 13, horizontal lines 701 to 732 are respectively printed by ejection from one ejection port of the recording head, as in the first embodiment. For example, 701 is recorded by the first ejection port, and the horizontal line 702 is recorded by the second ejection port. If the horizontal line is missing in such a test pattern shown in FIG. 13, the ejection port corresponding to that portion is not ejected. You can know that.

For example, the test pattern shown in FIG. 14 is the fifth pattern.
This indicates that ejection failure has occurred at the second ejection port.
If the non-ejection is not eliminated even if such non-ejection is detected and a predetermined ejection recovery process or the like is performed, the present example is applied.

First, the main control unit 103 is notified of which ejection port is not ejecting. This may be instructed from the host computer in response to the detection using the phototransistor described in the first embodiment, or the operator may input the fact via the operation / display panel 112. in any case,
The main control unit 103, which knows that the fifth ejection port is not ejected, performs recording using the 27th ejection ports of the 6th to 32nd ejection ports of the recording head 202. Change the control process.

That is, in normal recording, the recording data expanded in the bit map memory 105 shown in FIG. 2 is read in 32 bit × 32 bit units as shown in FIG. 4 and sent to the drive data buffer 108. When printing is performed using the ejection port of No. 2, as shown in FIG. 15, the data buffer 108 is changed to send data in units of 32 columns × 27 rows. However, the data corresponding to the five unused ejection ports, that is, the first 5 bits of each digit is "0".
Send as data first.

As shown in the first embodiment, when the ejection failure does not occur, the drive data buffer 108 shown in FIG.
As shown in FIG. 16A, 32 rows are sequentially written, and when reading is performed, up to 32 digits are sequentially read for each digit corresponding to the ejection opening arrangement of the print head as shown in FIG. It is sent to the recording head control unit 109. On the other hand, when non-ejection occurs, for example, when the fifth ejection port is non-ejection as in this example, the first to fifth ejection ports are not used and the sixth to sixth ejection ports are not used. Record using the 32nd outlet. Therefore, as shown in FIG.
As shown in 7 (A), first set the first five lines to "0",
Next, 27 rows are sequentially written for each row according to the recording data, and as shown in FIG. 17B, each digit consisting of 27 bits is sequentially read.

According to the above configuration, the paper is normally fed by the number of ejection openings, that is, 32 dots for each operation of the recording head. In the case of this example, the paper is fed by 27 dots.
The recording start position on the recording paper is also shifted by 5 dots in the direction opposite to the paper feed direction.

With the above arrangement, even when the non-ejection of the recording head is recovered, the recording can be performed using this recording head.

In the above embodiment, the 27th discharge ports after the sixth are used, but for example, the third discharge port is used.
When the 0th ejection port is not ejected, the 1st to 29th
Recording may be performed using the second ejection port. At this time, the writing of data to the drive data buffer is carried out first by 32 × 39 bits, and thereafter, “0” data for 32 × 3 bits is sent. Further, the paper feed for each operation is set to 29 dots.

FIG. 18 is a block diagram of an ink jet recording apparatus according to a modified example of the second embodiment.

In this example, for example, when printing is performed by using the sixth to thirty-second ejection ports as in the second embodiment, first, drive data is written in the drive data buffer 108 in 32 × 32 bit units. Be done. That is, the arrangement of data at the time of writing to and reading from the drive data buffer is the same as in the normal case shown in FIG.

After that, the drive data read from the drive data buffer 108 is entirely shifted by the shifter 191 receiving the shift clock signal 192 from the read control section 111 five times. As a result, the data structure is
For example, it becomes like FIG.

The mask register 193 has a 32-bit structure and masks the data corresponding to the first to fifth ejection ports. Therefore, "07FFFFF" is written in hexadecimal notation.
The F gate data is stored in the AND gate 194. The AND gate 194 performs an AND operation on the data of this register and the data corresponding to the 1st to 5th ejection ports, and thereby the 1st to 1st.
The drive data corresponding to the fifth ejection port are all "0".

(Others) The present invention is provided with a means (for example, an electrothermal converter or a laser beam) for generating thermal energy as energy used for ejecting ink, particularly in the ink jet recording system. The present invention provides excellent effects in a recording head and a recording apparatus of the type in which the thermal energy causes a change in ink state. 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 recorded 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 as a result
This is effective because bubbles can be formed inside. Due to the growth and contraction of the bubbles, liquid (ink) is ejected through the ejection openings 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 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 specifications, U.S. Pat. No. 4,558,333, U.S. Pat. No. 44, which discloses a configuration in which a heat acting portion is arranged in a bending region.
The configuration 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 Japanese Patent Laid-Open No. 59-138461. That is, according to the present invention, recording can be surely and efficiently performed regardless of the form of the recording head.

Further, the present invention can be effectively applied to a full line type recording head having a length corresponding to the maximum width of a recording medium 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 or the ink from the main body of the apparatus by being mounted on 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 means, a cleaning means, a pressure or suction means 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.

Regarding the type or number of recording heads to be mounted, for example, only one is provided corresponding to a single color ink, or a plurality of inks having different recording colors and densities are supported. A plurality of pieces may be provided. That is, for example, the recording mode of the recording apparatus is not limited to the recording mode of only the mainstream color such as black, but may be either integrally formed of the recording heads or a combination of a plurality of them. The present invention is also very effective for an apparatus provided with at least one of full-color recording modes by color mixing.

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 for changing the state 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 a standing state. You may use the ink liquefied by. In any case, by applying heat energy such as ink that is liquefied by applying heat 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 54-56847 A or JP 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 of the present invention, besides the one used as an image output terminal of an information processing apparatus such as a computer, a copying apparatus combined with a reader or the like, and a facsimile apparatus having a transmitting / receiving function are provided. It may be a form or the like.

[0079]

As is apparent from the above description, according to the present invention, according to the above configuration, from the test pattern,
It is possible to read specific information in the case where ejection failure has occurred in the recording head, and thus it is possible to detect ejection failure.

Further, even when ejection failure occurs in a part of the ejection openings of the print head, the drive data can be associated with other normal ejection openings. Recording can also be performed by the head.

As a result, the reliability of the recording apparatus can be improved and the maintenance cost of the apparatus can be reduced.

[Brief description of drawings]

FIG. 1 is a schematic perspective view showing an inkjet recording apparatus according to an embodiment of the present invention.

FIG. 2 is a block diagram showing a control configuration of the inkjet recording apparatus shown in FIG.

FIG. 3 is a block diagram showing details of a driving data buffer shown in FIG.

FIG. 4 is a schematic diagram for explaining data writing to the drive data buffer.

5A and 5B are a schematic front view and a schematic sectional view, respectively, showing the configuration of an inkjet recording head according to an embodiment of the present invention.

6A, 6B, and 6C are schematic cross-sectional views for explaining the ejection principle of the inkjet recording head.

FIG. 7 is a schematic diagram showing a test pattern for non-ejection detection according to the first embodiment of the present invention.

FIG. 8 is a waveform diagram showing a detection signal of the test pattern.

FIG. 9 is a flowchart showing a non-ejection detecting process using the test pattern.

FIG. 10 is a waveform diagram for explaining another example of use of the detection signal of the test pattern.

FIG. 11 is a block diagram showing a control configuration of an inkjet recording apparatus according to a modified example of the first embodiment.

FIG. 12 is a waveform diagram showing a test pattern detection signal according to the modification.

FIG. 13 is a schematic diagram showing a test pattern according to a second embodiment of the present invention.

FIG. 14 is a schematic diagram showing the test pattern when ejection failure occurs in the recording head.

FIG. 15 is a schematic diagram for explaining writing of drive data to a drive data buffer according to the second embodiment.

16A and 16B are schematic diagrams for describing writing and reading of drive data to and from the drive data buffer when ejection failure does not occur in the print head according to the second embodiment.

17A and 17B are schematic diagrams for describing writing and reading of drive data when ejection failure occurs in the print head in the second embodiment.

FIG. 18 is a block diagram illustrating a control configuration of an inkjet recording apparatus according to a modified example of the second embodiment.

[Explanation of symbols]

 101 Input Control Unit 102 Input Buffer 103 Main Control Unit 104 ROM 105 Bitmap Memory 106 CPU 107 Character Pattern Generation Unit 108 Drive Data Buffer 109 Recording Head Control Unit 110 Recording Unit 111 Reading Control Unit 112 Operation / Display Panel 181 Waveform Shaping Circuit 183 Counter 184 Comparator 185 Constant generator 191 Shifter 193 Register 194 AND gate 201 Recording paper 202 Recording head 202N Discharge port 203 Motor 204 Sensor 205 Motor 206 Phototransistor 207 Light emitting diode 351-n Ink path Hn Electrothermal converter

Claims (3)

[Claims] 1. An inkjet recording apparatus for ejecting ink to a recording medium for recording, comprising: a recording head for ejecting ink; and a recording pattern for recording a test pattern on the recording medium by the recording head. An ink jet recording apparatus comprising: a test pattern recording unit; and a non-ejection detecting unit for detecting non-ejection of ink of the recording head from the test pattern on a recording medium. 2. An ink jet recording apparatus for ejecting ink to a recording medium for recording, comprising a plurality of ejection openings, and a recording head for ejecting ink from the plurality of ejection openings. Drive data supply means for supplying drive data for ejecting ink from the ejection openings corresponding to each of the plurality of ejection openings in the recording head, and drive data supplied from the drive data supply means, Head drive means for ejecting ink from each of the plurality of ejection openings, and when ink ejection failure occurs in a part of the plurality of ejection openings, drive data is supplied by the drive data supply means. An ink jet recording apparatus, comprising: a data supply control unit that changes according to an ejection port other than the ejection port that causes 3. The ink jet recording apparatus according to claim 1, wherein the recording head uses the thermal energy to generate bubbles in the ink, and ejects the ink when the bubbles are generated. .