JPH10235850A - Ink jet recording device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize a high speed and favorably accurate counting of the number of ink dischargings by a method wherein driving data, which are operated so as to correspond pixel groups to a plurality of discharging ports, are serially transferred in synchronous with a predetermined transfer clock through a same signal line so as to count the data alloted to a specified discharging port in the driving data. SOLUTION: Eight-bit data, which are transferred from signal lines 8D1 and 8D2 in synchronous with clock signals SCK1 and SCK2 and which correspond to heaters H1-H16, output signals LT1 and LT2 when the clock signals SCK1 and SCK2 stop, resulting in latching 8 but latches 501 and 502. Next, when signals ENB1 and ENB2 are outputted, signals corresponding to stuck data are supplied to respective transistors tr1-tr16 so as to heat the respective heaters H1-H16 in order to discharge ink from respective discharging ports. In addition, the output sides of decoders 509, 511 and 510 and 512 are connected to the J and K terminals of JK filpflops 513 and 514, so as to count only the data at a first scanning by counters 513 and 514.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an ink jet recording apparatus for performing recording by a set of a plurality of pixels formed by discharging ink.

[0002]

2. Description of the Related Art Generally, in an ink jet recording apparatus, it is important to count the number of driving data for ink ejection of a recording head. This is to determine the timing of recovery means for eliminating clogging of the ink ejection ports of the recording head or removing bubbles in the recording head, and to prevent fluctuation in the amount of ejected ink due to temperature rise of the recording head. This is an essential requirement for control or for detecting the remaining amount of ink in an ink tank that supplies ink to the print head.

[0003] For example, USP (US Patent) 47914
As disclosed in JP-A-35-35, US Pat. No. 4,910,528, a method is known in which the number of drive data for ejection of a print head is counted to perform temperature control and ejection control. Further, as disclosed in Japanese Patent Publication No. 05-19467, there is known an apparatus that counts the number of drive data for ejection of a recording head to detect the remaining amount of ink in an ink tank.

In recent years, the number of discharge ports of a recording head has tended to increase, for example, from 64 to 128, and the discharge frequency has also increased from 5 KHz to 10 KHz, and the resolution is also 300 dpi (dot per inch: 1 inch which is a number representing the pixel density). , From 300 dots forming characters and the like) to 600 dpi.

[0005] For this reason, the data transfer rate to the printhead is also very high, and in order to count the number of drive data for ejection of the printhead, it is necessary to secure a certain level of counting accuracy and operate at high speed. Have been.

As disclosed in Japanese Patent Publication No. H03-31352, there is a method of counting the number of drive data for ejection of a recording head at the expense of accuracy. It cannot be used for prediction.

In addition, in the ink jet recording system, if there is a variation in the amount of ink ejected from each ejection port, the density, which should be uniform, becomes non-uniform, and there is a problem that streaks or uneven density occur in an image. The occurrence of streaks and uneven density due to the uneven density has become a more important problem than ever with the increase in the number of ejection ports and the increase in resolution. Therefore, in the inkjet recording method, it is called a so-called multi-scan method. A printing method is often used.

The multi-scan method is a method in which a pixel group arranged in an example with respect to the scanning direction of a recording head is formed by a plurality of discharge ports, and stripes and density unevenness due to a variation in discharge amount of each discharge port. Besides, since the frequency of use of the discharge ports is made uniform, it is possible to prevent the life of the recording head from being shortened.

As the multi-scan system, various systems have been proposed in addition to the sequential multi-scan system disclosed in JP-A-5-330083.

[0010]

In the above-described conventional ink jet printing apparatus, for example, when data is transferred in parallel to a print head, each signal for transferring data is counted in order to count the number of data to be transferred. It is necessary to provide a counter for each line and add the data of each counter at high speed.

[0011] In the present technology, the number of counters can be easily realized by increasing the number of mounted devices. However, a special technique is used to add data of a large number of nozzles at the above-mentioned ejection frequency at high speed. Must be done, leading to a significant rise in costs.

The monochrome ink jet recording apparatus is not limited to the high speed, but the color ink jet recording apparatus having four recording heads is required to have the required high speed and electric power. The scale of the circuit becomes very large.

As described above, it is very difficult to count the number of drive data for the ejection of the recording head at a high speed while ensuring a certain level of counting accuracy in the temperature control of the recording head, the recovery operation, the detection of the remaining amount of ink, and the like. There was a problem that is.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and provides an ink jet recording apparatus capable of counting the number of ejection data of a recording head with high speed and high accuracy with a simple configuration. It is an object.

[0015]

The ink jet recording apparatus according to the present invention is constructed as follows.

(1) An ink jet recording apparatus for performing recording by using a recording head having a plurality of discharge ports for discharging ink, wherein the pixel group arranged in a line in the scanning direction of the recording head is A data operating means for operating drive data of the printhead so as to be formed corresponding to a plurality of ejection ports, and a serial for transferring the drive data to the printhead through the same signal line in synchronization with a predetermined transfer clock A transfer unit; and a counting unit that counts data assigned to a specific ejection port in the driving data.

(2) In the printing apparatus of the above (1), the counting means counts the driving data of the fixed ejection ports.

(3) In the printing apparatus of the above (1), the counting means is configured to partially count the ejection port drive data changed every time the printing head scans.

(4) In any one of the recording apparatuses (1) to (3), recovery control of each ejection port is performed according to the counting result of the counting means.

(5) In any one of the recording apparatuses (1) to (3), drive control of each ejection port is performed according to the counting result of the counting means.

(6) In any one of the recording devices (1) to (5), the remaining amount of ink is detected based on the counting result of the counting means.

(7) In any one of the recording devices (1) to (6), the recording head has a thermal energy generator for generating thermal energy for discharging ink.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First, a printing procedure in a multi-scan system in an ink jet recording apparatus will be described in detail with reference to FIGS.

FIG. 1 is a perspective view showing a schematic structure of a main part of a general ink jet recording apparatus. In the configuration shown in the figure, Y (yellow), M (magenta), C (cyan),
The recording heads 1Y, 1M, 1C, and 1K that eject K (black) inks have a conveying direction A (hereinafter referred to as a sub-scanning direction) of the recording paper 2 at an interval of 1/300 inch.
For example, there are provided 16 discharge ports arranged in two rows, and a heater for generating thermal energy used for discharge is provided in an ink path corresponding to each discharge port. Provided.

The heater generates heat by an electric pulse applied in accordance with the driving data, thereby causing film boiling in the ink. Ink droplets are ejected. The driving frequency of the heater, that is, the ejection frequency is, for example, 10 KHz.

The carriage 4 on which the recording head unit 1 composed of the heads 1Y, 1M, 1C and 1K is mounted.
Are two guide shafts 5A, which are slidably engaged in the main body.
While being guided by 5B, it moves in the CR and PT directions in the figure. The movement of the carriage 4 is performed, for example, by attaching a wire 8 stretched by a pulley to a part of the carriage 4 and moving the wire 8 by rotation of the carriage motor 102 via the pulley. The ink supplied to the recording heads 1Y, 1M, 1C, and 1K is stored in respective ink cartridges (not shown) in the carriage 4. This ink is supplied to each of the recording heads 1Y, 1Y via an ink supply path (not shown).
1M, 1C and 1K.

The flexible cables 7C, 7M, 7Y,
7K are connected to the recording heads 1Y, 1M, 1C, and 1K, respectively, so that a driving circuit (head driver) provided in a part of the recording head 7K is based on recording data from the control board 15 of the present apparatus. Drive signals and control signals can be transmitted.

The paper feed rollers 3A and 3B have their longitudinal directions extending in parallel with the guide shafts 5A and 5B. Is transported. Below the paper feed rollers 3A, 3B, similar paper feed rollers 6A, 6b are provided, which rotate with the conveyance of the recording paper 2, and rotate with the paper feed rollers 3A, 3B.
3B, the recording surface of the recording paper 2 is regulated to be flat.

In the above configuration, the recording heads 1Y, 1M, 1C, and 1K move as the carriage 4 moves.
Ink is ejected onto the recording surface of the recording paper 2, that is, a portion facing the above-described ejection port to perform recording.

FIG. 2 is a schematic diagram showing one recording head in the ink jet recording apparatus of FIG. 1 as viewed from the ejection direction. The recording head is scanned in the main scanning direction indicated by arrow B to perform printing. Note that scanning in the direction of arrow B is forward scanning, and scanning opposite to the direction of arrow B is backward scanning. In this embodiment, printing is performed during forward scanning.

In FIG. 2, reference numerals 201 to 216 denote respective ejection ports of the recording head. The recording head is composed of two rows of odd and even rows of each ejection port. / 30
There is a distance of 0 inch. The intervals between the discharge ports in each row are 1/300 inch, and the discharge ports in both rows are arranged in a zigzag pattern. That is, the recording head has a resolution of 1/600 inch in the direction perpendicular to the scanning direction.

FIG. 3 is a block diagram showing a configuration of a control system of the ink jet recording apparatus of FIG.

The main controller 100 includes a CPU or the like, and temporarily stores character codes, image data, and the like sent from the host computer 200 in the memory 100M. The main controller 100 stores the character codes and image data stored in the memory 100M in the drive data RAM 110M via the driver controller 110 in correspondence with each scan of the recording head of each color.

The driver controller 110 reads the drive data stored in the drive data RAM 110M in response to a control signal from the main controller 100 and supplies the read drive data to the head driver 114.
The drive timing is controlled.

In the above configuration, the main controller 100 controls the ink ejection by the recording head, the rotation of the carriage motor 102 and the rotation of the paper feed motor 104 by the driver controller 110 and the motor driver 10 respectively.
Control is performed via the 4D and the motor driver 102D. Thus, characters, images, and the like corresponding to the image data are recorded on the recording paper 2.

FIG. 4 is a diagram schematically showing a printing operation when printing is performed in four scans by the sequential multi-scan method using the above-described recording head, and the printing operation will be described below with reference to FIG.

In the case of four scans, four different discharge ports of the print head pass over the same pixel. In this example, nozzle #
No. 1 (discharge port 201), nozzle # 5 (discharge port 205), nozzle # 9 (discharge port 209), and nozzle # 13 (discharge port 2)
13), nozzle # 2 (discharge port 202), nozzle # 6
(Discharge port 206), nozzle # 10 (discharge port 210) and nozzle # 14 (discharge port 214), nozzle # 3 (discharge port 203), nozzle # 7 (discharge port 207), nozzle # 11
(Discharge port 211) and nozzle # 15 (discharge port 214)
Nozzle # 4 (discharge port 204), nozzle # 8 (discharge port 208), nozzle # 12 (discharge port 212), and nozzle #
The recording paper is also fed by a distance corresponding to four nozzles so that the nozzles 16 (discharge ports 216) pass on the same pixel.

Here, it is assumed that a part of the pixel data sent from the host computer 200 is as shown in FIG. After temporarily storing the image data in the memory 100M, the main controller 100 stores the image data in the drive data RAM 110M via the driver controller 110 in correspondence with each scan of the recording head of each color. Hereinafter, the process at that time will be described.

The main controller 100 has a memory 10
The data on 0M is checked for the scanning direction of the print head, and numbers from "1" to "4"("1" to "n" for n-times scanning) are sequentially assigned to the drive data. This assigned number corresponds to the number of scans,
If “1” is assigned, printing is performed in the first scan. This number is stored in the drive data RAM 110M as a scan number referenced by the driver controller 110.

The driver controller 110 reads the drive data stored in the drive data RAM 110M with reference to the ejection port number and the scan number, and supplies the read data to the head driver 114 to perform ink ejection.

FIG. 4B shows a change in the recording result when the recording of the image data in FIG. 4A is performed according to the above-described procedure.

In this example, nozzles # 13 to # 16
Always performs the recording of the first scan drive data. Similarly, nozzles # 9 to # 12 always perform the second scan drive data, and nozzles # 5 to # 8 always perform the third scan drive data. Nos. 5 to # 8 always record the third scan data, and nozzles # 1 to # always record the fourth scan data.

(First Embodiment) FIG. 5 is a block diagram showing the configuration of a first embodiment of the present invention. The drive data transfer section and the heating section of each ejection port of the recording head shown in FIG. FIG. 4 is a diagram illustrating a configuration and a configuration for one color included in the main controller 100 and the driver controller 110 illustrated in FIG. 3 (there is no difference depending on the recording head of each color). Can be counted.

In FIG. 5, H1 to H16 are heaters for generating the above-mentioned heat energy provided corresponding to the respective discharge ports in FIG. 2, and tr1 to tr16 are heaters H1 to H16.
16 for driving the heaters H1 to H1.
It is provided corresponding to H16.

Reference numerals 501 and 502 denote 8-bit latches (Latch) which are data operation means.
The drive data of H16 is latched by the signals of LT1 and LT2. Reference numerals 503 and 504 denote serial transfer means 8b
It shift register (Shitr Register)
In r), the drive data for the heaters H1 to H16 is transferred through the signal lines SD1 and SD2 in synchronization with the transfer clock signals of SCK1 and SCK2, respectively.

Reference numerals 505 and 506 denote counters (Counters) as counting means for counting the number of drive data.
507 and 508 are 3 bits for counting the transfer clock
The output side of the counter 507 is a decoder (D
The output side of the counter 508 is connected to decoders 511 and 514, respectively.

The outputs of the decoders 509 and 511 are connected to the J input terminals of the JK flip-flops 513 and 514, and the outputs of the decoders 510 and 512 are connected to the K input terminals of the JK flip-flops 513 and 514. . These JK flip-flops 513 and 514
This is for controlling the counters 505 and 506 for counting the number of drive data.
Counting is performed only when the outputs of 13, 514 are "H".

In the above configuration, the clock signal SCK1
The data corresponding to each of the heaters H1 to H16 is transferred from each of the signal lines SD1 and SD2 in synchronization with SCK2 and SCK2. At this time, data from the odd-numbered heaters H15 to H1 and data from the even-numbered heaters H16 to H2 are transferred. That is, the clock signal SCK1
And SCK2 are sent by 8 each.

Next, the above eight data are transferred,
When the clock signals SCK1 and SCK2 stop, the signal L
T1 and LT1 are output, and the data transferred so far is latched by 8-bit latches 501 and 502, respectively. That is, data corresponding to the heaters H1 to H16 is held in the 8-bit latches 501 and 502.

Next, when the signals ENB1 and ENB2 are output, signals corresponding to the data held in the 8-bit latches 501 and 502 are output from the transistors tr1 to tr.
r16, and based on the data, each heater H1
To H16 are heated, and ink is ejected from each ejection port. At the same time as the signals ENB1 and ENB2 are supplied and ink ejection is performed, data relating to the next ink ejection is transferred to the 8-bit shift registers 503 and 504 in synchronization with the clock signals SCK1 and SCK2, respectively.

Thereafter, the sequence of ink ejection is similarly repeated, and an image is formed on recording paper. Note that the signal E
Since NB1 and ENB2 are signals from one signal line, the heaters H1 to H15 and the heaters H2 to H16 are heated at the same time, but by using a plurality of signal lines,
It is also possible to shift the ejection timing of each of the heaters H1 to H16.

The outputs of the decoders 509 and 511 are
"H" when the outputs of the counters 507 and 508 are "7"
(High level), and the outputs of the decoders 510 and 512 become "H" when the inputs, that is, the outputs of the counters 507 and 508 are "8". Therefore, the counters 507 and 508
Counts only the drive data of nozzles # 13 to # 16. That is, the counters 507 and 508 for counting the number of drive data count only the data of the first scan.

As is clear from the above description, only one-fourth of the data of all the ejection ports is counted in this embodiment, but the frequency of use of each ejection port is made uniform by the sequential multi-scan method. By multiplying the count value by four, it is possible to easily and accurately estimate the data of all the ejection ports. Therefore, the counter 50
The maximum count number of 7,508 is also one of the data numbers of all ejection ports.
/ 8.

Further, in this embodiment, there is no problem in terms of accuracy, and since the total number of bits of the counters 507 and 508 is 1/8, the speed is excellent and the load on hardware is reduced.

(Second Embodiment) FIG. 6 is a block diagram showing the configuration of a second embodiment of the present invention. As in the first embodiment, the driving of each ejection port of the recording head shown in FIG. 4 shows the configuration of a data transfer unit and a heating unit, and the configuration of the main controller 100 and the driver controller 110 shown in FIG.

In FIG. 6, parts having the same functions as those in FIG. 5 are given the same numbers. In the present embodiment, a 3-bit counter 507 for counting the transfer clock signal
Are output from the comparators 601, 6
The output side of the counter 508 is connected to one input terminal of the comparators 603 and 604, respectively. The other input terminals of the comparators 601 to 604 are connected to the outputs of registers (registers) 605 to 608 that can be rewritten by the main controller 100.

The outputs of the comparators 601 and 603 are connected to the J input terminals of JK flip-flops 513 and 514, respectively.
Output sides of the comparators 602 and 604 are connected to K input terminals of JK flip-flops 513 and 514, respectively. The JK flip-flops 513 and 514 are for controlling the counters 505 and 506 for counting the number of drive data, as in the first embodiment.
The counting is performed only when the outputs of the K flip-flops 513 and 514 are “H”.

In this embodiment, it is possible to count not only the number of drive data having a different number of scans for an even number and an odd number, but also to freely change the number of scans to be counted. Therefore, even in a multi-scan system inferior to the sequential multi-scan system in terms of equalizing the frequency of use of the ejection ports, high counting accuracy can be ensured by randomly changing the number of scans, for example, every four scans. Becomes possible.

The present invention is particularly directed to a recording head of the type utilizing the thermal energy among ink jet recording types,
In a recording apparatus, an excellent effect is provided.

The typical configuration and principle are described in, for example, US Pat. Nos. 4,723,129 and 4,740.
It is preferable to use the basic principle disclosed in the specification of Japanese Patent No. 796. This method is a so-called on-demand type,
Although it can be applied to any type of continuous type, in particular, in the case of the on-demand type, it can be applied to a sheet holding liquid (ink) or an electrothermal converter arranged corresponding to the liquid path. By applying at least one drive signal corresponding to recorded information and giving a rapid temperature rise exceeding nucleate boiling, heat energy is generated in the electrothermal transducer, and film boiling occurs on the heat-acting surface of the recording head. As a result, air bubbles in the liquid (ink) can be formed in one-to-one correspondence with the drive signal, which is effective.

The liquid (ink) is ejected through the ejection opening by the growth and contraction of the bubble to form at least one droplet. When the drive signal is formed into a pulse shape, the growth and shrinkage of the bubble are performed immediately and appropriately, so that the ejection of a liquid (ink) having particularly excellent responsiveness can be achieved, which is more preferable. As the pulse-shaped drive signal, US Pat.
Those described in 463,359 and 4,345,262 are suitable. Incidentally, US Pat. No. 4,431,131 of the invention relating to the temperature rise rate of the heat acting surface.
If the conditions described in the specification of JP-A No. 24 are adopted, more excellent recording can be performed.

As the configuration of the recording head, in addition to the combination of the discharge port, the liquid path, and the electrothermal converter (linear liquid flow path or right-angled liquid flow path) as disclosed in the above-mentioned respective specifications, U.S. Pat. No. 4,558,333 and U.S. Pat.
A configuration using the specification of Japanese Patent No. 459600 is also included in the present invention. In addition, Japanese Unexamined Patent Publication (Kokai) No. 123670/1984 discloses a configuration in which a common slit is used as a discharge portion of an electrothermal converter for a plurality of electrothermal converters, and an aperture for absorbing pressure waves of thermal energy. The effect of the present invention is effective even if the configuration is based on Japanese Patent Application Laid-Open No. 138461/1984, which discloses a configuration in which is adapted to a discharge unit.

[0063]

As described above, according to the present invention,
A simple hardware configuration that can be realized has the effect of being able to count the number of ejection drives of the print head at high speed and with high accuracy.Therefore, it is possible to control the print head temperature control, recovery operation control, ink remaining amount detection, etc. Appropriate control can be performed.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a schematic configuration of an ink jet recording apparatus.

FIG. 2 is a schematic diagram illustrating a recording head of the inkjet recording apparatus of FIG. 1;

FIG. 3 is a block diagram illustrating a configuration of a control system of the inkjet recording apparatus of FIG. 1;

FIG. 4 is an explanatory diagram showing a sequential multi-scan printing operation.

FIG. 5 is a block diagram showing the configuration of the first embodiment of the present invention.

FIG. 6 is a block diagram showing a configuration of a second exemplary embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Recording head unit 1K Black ink recording head 1C Cyan ink recording head 1M Magenta ink recording head 1Y Yellow ink recording head 2 Recording paper 4 Carriage 100 Main controller 100M Frame memory 102 Carriage motor 102D Motor driver 104 Paper feed motor 104D Motor driver 110 Driver Controller 110M Drive data RAM 114 Head driver 200 Host computer 501 Latch (data operating means) 502 Latch (data operating means) 503 Shift register (serial transfer means) 504 Shift register (serial transfer means) 505 Counter (counting means) 506 Counter ( Counting means) 507 counter 508 counter 509 decoder 510 decoder 11 decoder 512 decoder

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Takehiko Kasamatsu 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc.

Claims (7)

[Claims] 1. An ink jet recording apparatus which performs recording using a recording head having a plurality of discharge ports for discharging ink, wherein the plurality of pixel groups are arranged in a line in a scanning direction of the recording head. Data operating means for operating the drive data of the printhead so as to be formed corresponding to the discharge ports of the printer, and serial transfer for transferring the drive data to the printhead through the same signal line in synchronization with a predetermined transfer clock Means for counting data assigned to a specific discharge port in the drive data. 2. The ink jet recording apparatus according to claim 1, wherein the counting means counts the driving data of the fixed ejection port. 3. The ink jet recording apparatus according to claim 1, wherein the counting means counts a part of the ejection port drive data changed every time the recording head scans. 4. A recovery control for each discharge port according to a counting result of a counting means.
The ink jet recording apparatus according to any one of the above. 5. The driving control of each discharge port according to the counting result of the counting means.
The ink jet recording apparatus according to any one of the above. 6. The method according to claim 1, wherein the remaining amount of the ink is detected based on a counting result of the counting means.
The ink jet recording apparatus according to any one of the above. 7. An ink jet recording apparatus according to claim 1, wherein said recording head has a thermal energy generator for generating thermal energy for discharging ink.