JP3376347B2 - Ink jet recording device - Google Patents

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 performing color recording using a plurality of multi-nozzle heads having a plurality of nozzles.

[0002]

2. Description of the Related Art Conventionally, in a color copying apparatus using an ink jet recording apparatus for performing color recording with a plurality of multi-nozzle heads, a document to be copied is read by a sensor, and red (R), green (G) and Each signal of blue (B) is converted into each component of cyan (C), magenta (M), yellow (Y) and black (BK) by a masking table, and each converted signal is turned ON / OFF of each nozzle. Binarization was performed so that the signal turned off, and color copying was performed.

[0003]

However, in the above-mentioned conventional example, when a non-ejection portion occurs in the BK nozzle due to clogging or other causes, the printing operation is performed as a whole without ejecting the corresponding nozzle. Therefore, in the formed copy image, a portion not to be recorded exists as if one line is drawn, and an unfinished image is output.

An object of the present invention is to provide an ink jet recording apparatus which can form a clear image even if there is a non-ejection nozzle in the black nozzle.

[0005]

In order to achieve the above-mentioned object, an ink jet recording apparatus according to the present invention has a plurality of ink jet heads each having a plurality of nozzles arranged corresponding to a plurality of inks of different colors. In an inkjet recording apparatus that performs recording by ejecting ink from nozzles of the plurality of inkjet heads according to an ejection signal corresponding to each nozzle, the inkjet head that ejects ink of a predetermined color is A storage unit that stores information about positions of nozzles in a non-ejection state in an array of a plurality of nozzles, and a primary color signal that includes a specific plurality of colors different from the plurality of colors, and a plurality of inks that correspond to the plurality of inkjet heads. With an output means that converts to a signal corresponding to each color and outputs Then, based on the information stored in the storage means, the signal corresponding to the position of the nozzle in the non-ejection state of the inkjet head corresponding to the ink of the predetermined color is not output, and the predetermined color is output. Among the plurality of nozzles of the ink jet head corresponding to the inks other than the above, the output unit converts the signal of the nozzle corresponding to the nozzle in the non-ejection state of the predetermined color and outputs the signal.

Here, the ink jet recording apparatus of the present invention is provided with a reading unit for reading the original image, and can copy and record the original image read by the reading unit. Further preferably, the inkjet head is
Bubbles are generated in the ink by using thermal energy, and the ink is ejected from the nozzle based on the generation of the bubbles.

[0007]

According to the present invention, in an ink jet recording apparatus which uses a multi-nozzle head having a plurality of nozzles corresponding to a plurality of different colors, among the plurality of ink jet nozzles that eject ink of a predetermined color, non-ejection occurs. In the configuration in which the information about the position of the nozzle in which the occurrence is generated is stored and the signal for recording corresponding to each of the plurality of nozzles of the plurality of inkjet heads is output, the signal corresponding to the position of the nozzle in the non-ejection state is output. Of the nozzles corresponding to the inks other than the predetermined color without performing the above, and outputting the signals corresponding to the nozzles corresponding to the inks other than the predetermined color. Even if non-ejection occurs, the non-ejection portion is made inconspicuous without adversely affecting the formed image. It is possible.

[0008]

Embodiments of the present invention will be described below with reference to the drawings.

[Embodiment 1] FIG. 1 shows an outline of a copying apparatus to which the ink jet recording apparatus of the present invention is applied. In the figure, 1 is an original to be copied, 2 is a light source for reading the original, 3 is a sensor for reading the original, and 4 is an output signal of the sensor for reading the original. An A / D converter for converting an analog signal into a multi-valued R, G, B digital signal, and 5 are respective components of ink for recording the multi-valued R, G, B digital signal. . A masking table for converting into C, M, Y, BK, 6 is a binarizing device for converting each converted multi-valued C, M, Y, BK signal into a binary signal, and 7 is A recording control device for driving and controlling each multi-nozzle head by the binarized C, M, Y, and BK signals, 8 a cyan multi-nozzle head, and 9 a magenta multi-nozzle head. 10 is a yellow multi-nozzle head, 11 is a black multi-nozzle head, and 12 is C, M, Y, BK for recording.
An arithmetic unit for performing arithmetic operations such as various comparisons with respect to each of the signals, and a storage unit 13 for holding data used for arithmetic operations by the arithmetic unit 12. The operation will be described with reference to the drawings.

The original 1 to be copied is read by the sensor 3 by the light source 2, and the output signal of the sensor which is an analog signal is converted by the A / D converter 4 into digital signals of R, G and B, respectively. The converted R, G, B signals are decomposed into multivalued digital signals by the masking table 5 in order to be converted into C, M, Y, BK for recording. further,
The binarization device 6 converts a multi-valued digital signal of C, M, Y, BK into binary digital data for recording control, and uses the binary digital data of C, M, Y, BK. The recording control device 7 drives and controls each multi-nozzle head to form a copied image.

FIG. 2 shows the state of recording dots when all the BK multi-nozzle heads 11 are made to perform the ejection operation. FIG. 2 shows a state where the m-th nozzle is not ejected out of the n nozzles. When the presence of the non-ejection nozzle is confirmed during the copying operation or during the inspection of the apparatus, for example, the image formed by the photosensor can be scanned to know the number of the non-ejection nozzle. Then, the non-ejection nozzle is replaced with the storage device 13.
Can be stored in.

When the non-ejection nozzle as shown in FIG. 2 exists, the control as shown in FIG. 3 is carried out when actually printing. That is, since the number of the non-ejection nozzle among the BK nozzles is stored in the storage device 13 in advance, whether or not the ejection signal for each BK nozzle corresponds to the stored non-ejection nozzle is determined. The arithmetic unit 12 determines. Then, as shown in FIG. 3, when the ejection signal 1 is applied to the m-th BK nozzle which is not ejected, that is, when the ejection is ON, the arithmetic unit informs the recording control device 7 that the corresponding signal is unsuitable. Other C, M,
The signal of each m-th nozzle of Y is set to 0, that is, ejection OF
The state of F is changed to 1, that is, the state of discharge is ON, and the discharge is performed. As a result, for the m-th nozzle, black is generated by the color mixture of C, M, and Y instead of BK, and recording is performed. This makes BK noticeable when there is a non-ejection portion.
Even if the discharge nozzle exists, an image in which the non-discharge portion is eliminated can be generated by the alternative recording using C, M, and Y.

[Second Embodiment] FIG. 4 shows another embodiment of the present invention. In the figure, reference numeral 14 denotes a plurality of R, G, B signals obtained by A / D converting an analog signal output from a document and converting the signals into C, M, Y, BK signals for recording. Masking table with masking factor of 6
Is a binarization device for converting multi-valued C, M, Y, and BK signals into two values so as to match the ejection of the multi-nozzle head, and 7 is for driving by the multi-nozzle head.
A recording control device for controlling, 8 is a cyan multi-nozzle head, 9 is a magenta multi-nozzle head, 10 is a yellow multi-nozzle head, 11 is a black multi-nozzle head, and 12 is a comparison with each ejection signal data. An arithmetic device 13 for performing the above is a storage device that stores in advance which nozzle is a non-ejection nozzle in each of the C, M, Y, and BK multi-nozzles, and also transfers the data to the arithmetic device 12 and the like. . The operation will be described with reference to FIG. When the BK nozzle is not non-ejecting for the portion to be printed, the RGB signals input to the masking table are multi-valued by the masking table according to the ratio of R, G, B components as shown in FIG. M, Y, B
It is converted into a signal of each component of K. But applicable BK
When the nozzle of No. is not ejected, that is, when a certain nozzle to be converted from R, G, B to C, M, Y, BK matches the nozzle stored in the storage device 13 in advance, the arithmetic unit 13 Convert the masking table to use. As a result, as shown in FIG. 5B, the R, G, and B signals do not use BK corresponding to the R, G, and B components, C, M, and
It is converted into a multi-valued signal of each component of Y, and BK is 0, that is, there is no BK component. The signal converted into C, M, Y, and BK including the non-ejection portion of the nozzle in this way is binarized by the binarization device 6 to be a signal for ejection, and C, M by the recording control device 7, Recording is performed by driving the M, Y, and BK multi-nozzle heads. This allows
Especially for BK that affects the image when there is a non-ejection portion, by using the conversion from R, G, B to only C, M, Y, it is possible to perform printing without adverse effects even if there is a non-ejection in the nozzle of BK. It can be carried out.

Further, from R, G, B to C, M, Y, BK
By changing the masking table for conversion, C or M
Even if the multi-nozzle head has a non-ejection portion, it is possible to supplement the non-ejection portion with another color by converting into a similar color component.

Furthermore, not only from the R, G, B components of the original reading by copying the original, but also by the external input to the copying apparatus, that is, the input of R, G, B or C, M, Y. , BK can be input in the same manner.

(Others) In particular, the present invention includes 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. The present invention brings about excellent effects in a recording head and a recording apparatus of the type in which the state of ink is changed by the heat energy. This is because such a system can achieve high density recording and high definition recording.

With regard to 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 bubbles can be immediately and appropriately grown and contracted, so that liquid (ink) ejection 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 respective 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.

Furthermore, the present invention can be effectively applied to a full-line type recording head having a length corresponding to the maximum width of a recording medium which can be recorded by the recording apparatus. Such a recording head may have a configuration that satisfies the length by a combination of a plurality of recording heads or a configuration as one recording head integrally formed.

In addition, even in the case of the serial type as in the above example, the recording head fixed to the main body of the apparatus or the electrical connection to the main body of the apparatus and the ink from the main body of the apparatus by being attached to the main body of the apparatus. The present invention is also effective when a replaceable chip-type recording head that can be supplied or a cartridge-type recording head in which an ink tank is integrally provided in the recording head itself is used.

Further, as the constitution of the recording apparatus of the present invention, it is preferable to add an ejection recovery means of the recording head, a preliminary auxiliary means and the like because the effect 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.

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 it may be either the recording head is integrally formed or a plurality of combinations may be used. The present invention is also extremely 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 ink jet system, it is common to adjust the temperature of the ink itself within the range of 30? To 70? 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. The ink in such a case is disclosed in JP-A-54-56847 or JP-A-60-712.
As described in Japanese Patent Laid-Open No. 60, 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 a form of the ink jet recording apparatus of the present invention, in addition to 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.

[0025]

As described above, according to the present invention,
By using the nozzles of the same location of the multi-nozzle head of another color to compensate for the location corresponding to the non-ejection nozzle portion of the multi-nozzle head corresponding to a predetermined color, the image is compensated by the ejection from the nozzle of another color. You can make a clean recording without any disturbance.

[Brief description of drawings]

FIG. 1 is a block diagram showing an outline of a copying apparatus embodying the present invention.

FIG. 2 is a diagram showing a printing state of a BK nozzle head.

FIG. 3 is a diagram showing another nozzle ejection method for the BK nozzle printing shown in FIG.

FIG. 4 is a block diagram showing an outline of another embodiment of the copying apparatus.

5 is a diagram showing a change of the masking table in FIG.

[Explanation of symbols]

1 Manuscript to be copied 2 light sources 3 reading sensor 4 A / D converter 5 Masking table 6 Binarization device 7 Print control device 8 Cyan multi-nozzle head 9 Magenta multi-nozzle head 10 Yellow multi-nozzle head 11 Black multi-nozzle head 12 arithmetic unit 13 Storage device 14 Masking table

Claims (10)

(57) [Claims] 1. A plurality of ink jet heads, each having a plurality of nozzles arranged therein, are used corresponding to a plurality of inks of different colors, and the nozzles of the plurality of ink jet heads are used in accordance with ejection signals corresponding to the respective nozzles. In an inkjet recording apparatus that ejects ink to perform recording, a storage unit that stores information regarding the position of a nozzle in a non-ejection state in an array of a plurality of nozzles of the inkjet head, for an inkjet head that ejects ink of a predetermined color An output unit that converts a primary color signal composed of a plurality of specific colors different from the plurality of colors into a signal corresponding to each of a plurality of ink colors corresponding to the plurality of inkjet heads and outputs the signal. The ink corresponding to the predetermined color ink based on the information stored in the means. The non-ejection state of the predetermined color among the plurality of nozzles of the ink jet head that does not output the signal corresponding to the position of the non-ejection nozzle of the jet head and corresponds to the ink other than the predetermined color And an output unit that outputs the signal of the nozzle corresponding to the nozzle of FIG. 2. The output means comprises a plurality of specific colors.
An ink jet recording apparatus according to claim 1, characterized in that the primary color signals, a masking means for the plurality of inkjet heads, and outputs the converted into signals corresponding to each color of the plurality of ink corresponding according masking table . 3. The masking means converts the primary color signal corresponding to the position of the nozzle in the non-ejection state into a signal corresponding to ink other than the predetermined color based on the information stored in the storage means. The inkjet recording apparatus according to claim 2, wherein the inkjet recording apparatus converts and outputs the converted data. 4. The masking means converts the primary color signal corresponding to the position of the nozzle in the non-ejection state, and the primary color signal corresponding to positions other than the position of the nozzle in the non-ejection state. 4. A masking table for performing the operation is different.
The inkjet recording device according to item 1. 5. The masking means converts the multi-valued primary color signals into multi-valued signals corresponding to the respective colors of the plurality of inks and outputs the multi-valued signals. An inkjet recording device according to claim 1. 6. The ink jet recording apparatus according to claim 5, further comprising a binarizing unit that binarizes a signal corresponding to each color of the plurality of inks output from the masking unit. 7. The primary color signal is a signal corresponding to three primary colors of R, G and B, and the colors of the plurality of inks corresponding to the plurality of inkjet heads are cyan, magenta, yellow and black. 7. The inkjet recording device according to claim 2, wherein the inkjet recording device is an inkjet recording device. 8. The ink jet recording apparatus according to claim 1, wherein the predetermined color is black. 9. The ink jet recording apparatus according to claim 1, further comprising a reading unit for reading the original image, and performing copy recording of the original image read by the reading unit. 10. The ink jet head uses the thermal energy to generate bubbles in the ink, and ejects the ink from the nozzles based on the generation of the bubbles. The inkjet recording device according to item 1.