JP2002029056A - Liquid discharge head, head cartridge using the same, and image-forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem that white streaks are generated when solid prints are formed because ink drops discharged from discharge ports present at both ends in an arrangement direction of the ports in an ink jet printer are unevenly brought to the center in the arrangement direction. SOLUTION: The liquid discharge head has a plurality of discharge ports 16 arranged along a transfer direction for a printing medium and a plurality of discharge energy-generating parts 13 arranged opposite to the discharge ports for letting a liquid discharged from the discharge ports 16. The liquid discharge head which scans and moves along the printing medium in a direction intersecting the transfer direction for the printing medium makes a deviation quantity between an axis of the discharge port 16 and a center position of the corresponding discharge energy-generating part 13 different between the central part and end parts along the arrangement direction of the discharge ports 16.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid discharge head having a discharge port for discharging liquid, a head cartridge using the same, and an image forming apparatus.

[0002] In this specification, the term "print" means not only the case where significant information such as characters and figures are formed, but also whether the information is significant or insignificant and which is manifested so that humans can perceive it visually. Regardless of whether or not the image is formed, a case where an image, a pattern, a pattern, or the like is widely formed on a print medium or a case where the medium is processed is also included. The “print medium” includes not only paper used in a general printing apparatus but also an ink-acceptable material such as cloth, plastic film, metal plate, glass, ceramics, wood, and leather. Further, “ink” (sometimes described as “liquid”) should be interpreted broadly as in the definition of “print” described above. Any liquid that can be used for forming or processing of a print medium or processing of ink (for example, coagulation or insolubilization of a coloring material in ink applied to a print medium), and thus can be used for printing. Inclusive.

[0003]

2. Description of the Related Art In recent years, with the spread of digital cameras on the Internet and the like, demand for high-gradation color printing has been increasing, and accordingly, the performance of ink jet printers has been improved. As means for obtaining high-definition, high-gradation, high-quality print images, the arrangement interval of ejection ports for ejecting ink has been narrowed,
Improve resolution. Prepare a plurality of print heads that respectively discharge a plurality of (at least two) color inks having different ratios of the colorants contained in the specific color inks, that is, different colorant densities. And light ink are selectively overprinted to improve gradation. The gradation is improved by making the size of the ink droplet ejected from the ejection port, that is, the ink amount variable.
Such methods are known.

A so-called bubble jet (registered trademark) type printer that uses thermal energy as ejection energy for ejecting ink from an ejection port of a print head, generates bubbles in the ink, and uses the foaming pressure at that time. In, the above-mentioned method is relatively difficult, so the second method is considered to be particularly effective.

However, if the above method is to be realized, two or more print heads are required for a specific color ink, resulting in an increase in cost. Therefore, in the bubble jet type printer, the arrangement interval of the ejection ports is narrowed as described above, and the size of each ink droplet ejected from each ejection port is reduced (for example, 10 picoliters or less) to improve the resolution. This method is the most desirable and simple method because it hardly increases the manufacturing cost.

When such small ink droplets are ejected from an ejection port, a method in which bubbles that grow due to film boiling accompanying heating of the ink are communicated to the atmosphere through the ejection port is disclosed in, for example, Japanese Patent Application Laid-Open No. Hei 4-10940. Patent Publication, Japanese Unexamined Patent Publication No. 4-1
A so-called bubble-through method is disclosed in Japanese Unexamined Patent Publication No. 0941, Japanese Patent Application Laid-Open No. 4-10742, etc., in order to distinguish the bubble growing by film boiling from a conventional bubble jet method in which ink droplets are ejected without communicating with the atmosphere. In some cases.

[0007] In a conventional bubble jet type print head in which ink droplets are ejected without communicating bubbles grown by film boiling to the atmosphere, the ink droplets ejected from the ejection ports are ejected as the size of the ink droplets is reduced. The cross-sectional area of the ink flow path communicating with the outlet must be reduced,
There is a problem that the ejection efficiency is reduced and the ejection speed of the ink droplet ejected from the ejection port is decreased. When the ejection speed of ink droplets decreases, the ejection direction becomes unstable, and
When the print head is stopped, the ink thickens due to the evaporation of water, the ejection state becomes more unstable, initial ejection failure or the like occurs, and reliability may be reduced.

[0008] In this regard, a bubble-through type print head in which bubbles communicate with the atmosphere can determine the size of an ink droplet only by the geometrical shape of the discharge port, and is therefore suitable for discharging small ink droplets. Less affected by temperature, etc.
It has the advantage that the ink droplet ejection volume is extremely stable compared to the conventional bubble jet print head, so it is relatively easy to obtain high-definition, high-gradation, high-quality print images. It is.

[0009]

In order to obtain a high-definition, high-gradation, high-quality print image, it is preferable to perform printing by discharging a very small amount of ink droplets from one discharge port. In this case, in order to increase the printing speed, it is necessary to discharge ink droplets from the discharge ports in a short cycle. In addition, the carriage on which the print head is mounted must be moved at high speed relative to the print medium in synchronization with the drive frequency of the print head. From such a viewpoint, it can be said that a bubble-through type is particularly suitable for an ink jet printer.

In a case where such an ink jet type print head is scanned and moved at a high speed along a print medium together with a carriage, ink droplets are continuously discharged from all discharge ports, so-called solid printing is performed on the print medium. FIG. 18 shows the ink droplet ejection state at this time. The scanning movement direction of the print head 1 is shown in FIG.
And the ejection openings (not shown) are arranged in the left-right direction in the figure. When the image data is solid, all the ejection energy generators (not shown) corresponding to each ejection port are driven at a high drive frequency. Therefore, with the movement of the ink droplet 3 ejected from the ejection port toward the print medium 2, the viscous air surrounding the ink droplet 3 also moves while being dragged by the movement of the ink droplet 3. As a result, the pressure in the vicinity of the discharge port surface 4 where the discharge ports of the print head 1 are opened tends to be lower than that in the vicinity of the print head 1, and particularly, the ink droplets 3 discharged from the discharge ports located at both ends in the arrangement direction of the discharge ports. It has been found that the ink is drawn toward the center in the arrangement direction and is not ejected to a desired position with respect to the print medium 2.

FIG. 19 schematically shows a solid print image formed on a print medium when a solid print is performed by scanning the carriage a plurality of times under such a phenomenon. The carriage scans together with the print head from the upper side to the lower side in the drawing. At this time, a white stripe 7 is formed between the solid image 5 formed by the previous scanning movement and the solid image 6 formed by the next scanning movement. Will be formed.

Such a problem is particularly remarkable in a bubble-through type ink-jet printer which can discharge a small amount of ink droplets of 10 picoliters or less at a high cycle by one driving operation by setting the arrangement interval of the discharge ports to be narrow. appear.

In order to prevent such a problem, the size of ink droplets ejected from the ejection ports located at both ends in the arrangement direction of the ejection ports is increased, that is, the inertial mass of the ink drops is increased. It is also possible to suppress the deviation of the ejection trajectory of the ink droplets ejected from the ejection ports located at both ends. However, enlarging the ink droplets is an obstacle to forming a high-definition and high-gradation image. Further, the penetration of the ink droplets into the print medium is delayed, and the swelling of the print medium is likely to cause deterioration of the printed image. Alternatively, it is also possible to alleviate the above-mentioned problem by suppressing the driving frequency for the ejection energy generation unit.
However, if the driving frequency for the ejection energy generating unit is set low, the printing speed becomes slow, and it is not possible to meet the needs of the user for printing out at high speed.

[0014]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a bubble-through type ink jet printer which can discharge a small amount of ink droplets of 10 picoliters or less at a high frequency by one driving operation. Provided is a liquid ejection head which suppresses deviation of ink droplets ejected from an ejection port to be formed and prevents a white streak even when a solid print is formed, a head cartridge using the liquid ejection head, and an image forming apparatus. It is in.

[0015]

According to a first aspect of the present invention, there is provided:
A plurality of ejection ports arranged along the transport direction of the print medium, and a plurality of ejection energy generation units arranged to face each of the ejection ports and ejecting liquid from the ejection ports; A liquid ejection head that scans and moves along the print medium in a direction that intersects a medium conveyance direction, the amount of displacement between an axis of the ejection port and a corresponding center position of the ejection energy generation unit. Are different between a center portion and an end portion of the discharge port along the arrangement direction.

According to a second aspect of the present invention, there is provided a head cartridge including the liquid discharge head according to the first aspect of the present invention and a liquid tank for storing liquid supplied to the liquid discharge head. It is in.

According to a third aspect of the present invention, there is provided a liquid ejecting head mounting portion according to the first aspect of the present invention, and means for transporting a print medium, wherein a liquid ejected from an ejection port of the liquid ejecting head is provided. An image forming apparatus for forming an image on a print medium.

According to the present invention, when the center of the discharge energy generating section and the axis of the discharge port are arranged in a straight line,
The droplet discharged from the discharge port is discharged along its axis. On the other hand, when the axis of the ejection port is displaced from the center of the ejection energy generating section, the droplet ejected from the ejection port is ejected in an inclined state with respect to the axis. Therefore, the axes of the ejection ports located at both ends are set at the center of the ejection energy generating section so that the ejection direction of the droplets ejected from the ejection ports located at both ends in the arrangement direction is away from the center in the arrangement direction. By shifting the position, the position of the droplet that finally reaches the print medium is corrected to a desired position.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the liquid discharge head according to the first embodiment of the present invention, the amount of displacement is a size along the arrangement direction of the ejection ports, and the amount of displacement at the central portion along the arrangement direction is small. In this case, the displacement at the end portion along the arrangement direction is formed in a direction in which the axis of the discharge port is away from the central portion along the arrangement direction with respect to the center position of the discharge energy generating portion. Is preferred. Further, the discharge energy generating portions may be formed at regular intervals, and the arrangement intervals of the discharge ports may be different between the center and the end. Alternatively, the discharge ports may be formed at regular intervals, and the arrangement intervals of the discharge energy generating sections may be different between the center and the end. Further, the discharge energy generating section may have an electrothermal converter for generating thermal energy for causing the liquid to discharge from the discharge port by causing film boiling of the liquid, and in this case, the bubble growing by the film boiling May be of a so-called bubble-through type that communicates with the atmosphere via a discharge port.

The amount of droplets discharged from the discharge port by driving the discharge energy generation unit once may be 10 picoliter or less.

In the head cartridge according to the second aspect of the present invention, the liquid tank may be detachably attached to the liquid ejection head via attaching / detaching means.

In the image forming apparatus according to the third aspect of the present invention, the mounting portion may have a carriage which can scan and move in a direction intersecting with the transport direction of the print medium. It may be mounted detachably on the carriage via the means. Further, the liquid may be a processing liquid for adjusting printability of the ink on the ink and / or print medium.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to a serial type ink jet printer will be described in detail with reference to FIGS. 1 to 17. However, the present invention is not limited to such an embodiment, and further combines these. Alternatively, it can be applied to other technologies that should be included in the concept of the present invention described in the claims of this specification.

1. Apparatus Main Body FIGS. 1 and 2 show a schematic configuration of a printer using an inkjet printing method. In FIG. 1, an outer shell of a printer main body M1000 of this embodiment includes an outer member including a lower case M1001, an upper case M1002, an access cover M1003, and a discharge tray M1004, and a chassis M3019 housed in the outer member.
(See FIG. 2).

The chassis M3019 is composed of a plurality of plate-like metal members having a predetermined rigidity, forms a skeleton of a printer, and holds each printing operation mechanism described later.

The lower case M1001 is connected to the apparatus main body M1.
000, and the upper case M1002 forms a substantially upper half of the outer shell of the apparatus main body M1000, and a combination of the two cases provides a storage space for storing each mechanism described later inside. It has a hollow body structure. An opening is formed in each of the upper surface and the front surface of the apparatus main body M1000.

Further, one end of the discharge tray M1004 is rotatably held by the lower case M1001 so that the opening formed on the front surface of the lower case M1001 can be opened and closed by the rotation. For this reason,
When executing the printing operation, the discharge tray M100
By rotating the opening 4 to the front side to open the opening, the print sheet can be discharged from here, and the discharged print sheets P can be sequentially stacked. Further, two auxiliary trays M1004a and M1004b are stored in the paper discharge tray M1004.
By pulling out each tray as needed, the sheet support area can be expanded or reduced in three stages.

One end of the access cover M1003 is rotatably held by the upper case M1002 so that an opening formed on the upper surface can be opened and closed. When the access cover M1003 is opened, the inside of the main body is opened. The stored head cartridge H1000 or ink tank H1900 can be replaced. Although not particularly shown here, the access cover M10
When the cover 03 is opened and closed, a projection formed on the back surface rotates the cover opening / closing lever, and the open / closed state of the access cover can be detected by detecting the rotation position of the lever with a microswitch or the like. It has become.

A power key E0018 and a resume key E001 are provided on the rear upper surface of the upper case M1002.
9 is provided so as to be able to be pressed, and LED E0020
Is provided, and when the power key E0018 is pressed,
The LED E0020 is turned on to notify the operator that printing is possible. Also, LE
The DE0020 has various display functions, such as changing the blinking method and color, and notifying the operator of a printer trouble or the like. Further, the buzzer E0021 (FIG. 7) can be smoothed. When the trouble is solved, printing is resumed by pressing the resume key E0019.

2. Next, the print operation mechanism according to the present exemplary embodiment, which is stored and held in the apparatus main body M1000 of the printer, will be described.

The print operation mechanism in this embodiment includes an automatic feeding unit M3022 for automatically feeding the print sheet P into the apparatus main body, and a print sheet P sent one by one from the automatic feed unit. A transport unit M3029 for guiding the print sheet P from the print position to the discharge unit M3030 while guiding the print sheet P to a desired print position, a print unit for performing a predetermined print on the print sheet P transported to the print position, the print unit, and the like. And a recovery unit (M5000) for performing a recovery process for.

Here, the printing section will be described.
The printing unit includes a carriage M4001 movably supported by a carriage shaft M4021, and a head cartridge H1000 removably mounted on the carriage M4001 via attaching / detaching means (not shown).

2.1 Head Cartridge First, a head cartridge used in the printing section will be described with reference to FIGS.

The head cartridge H in this embodiment
As shown in FIG. 3, reference numeral 1000 denotes an ink tank H1900 for storing ink, and a print head H1001 for discharging ink supplied from the ink tank H1900 from nozzles according to print information. The print head H1001 includes a carriage M4001 described later.
So-called cartridge type, which is removably mounted on the printer.

The head cartridge H1000 shown here
In order to enable photographic high-quality color prints, ink tanks such as black, light cyan,
An independent ink tank H1900 for each color of light magenta, cyan, magenta and yellow is provided, and is provided in each ink tank H1900 and is an elastically deformable detachable lever which can be locked to the head card ridge H1000. By operating the H1901, each can be detached from the print head H1001, as shown in FIG. Therefore, the removal lever H1901 functions as a part of the attachment / detachment means of the present invention.

As shown in an exploded perspective view of FIG. 5, the print head H1001 includes a print element substrate H1100, a first plate H1200, an electric wiring substrate H1300, a second plate H1400, a tank holder H1500, and a flow path forming member H1600. , A filter H1700, and a seal rubber H1800.

On the printed element substrate H1100, a plurality of printed elements for discharging ink on one side of the Si substrate and electric wiring such as aluminum for supplying power to each printed element are formed by a film forming technique. A plurality of ink flow paths and a plurality of ejection ports H11 corresponding to print elements
00T is formed by a photolithography technique, and an ink supply port for supplying ink to a plurality of ink flow paths is formed so as to open on the back surface. The printed element board H1100 is the first plate H1.
200, an ink supply port H1201 for supplying ink to the print element substrate H1100 is formed. Further, the first plate H1200 has a second plate H14 having an opening.
00 is adhered and fixed, and the second plate H14
00, the electric wiring board H1300 is held so as to be electrically connected to the printed element board H1100. The electric wiring board H1300 is for applying an electric signal for discharging ink to the printed element board H1100. The electric wiring corresponding to the printed element board H1100 and the electric wiring located at the end of the electric wiring and from the main body. External signal input terminal H130 for receiving signals
The external signal input terminal H1301 is positioned and fixed to the back side of a tank holder H1500 described later.

On the other hand, a flow path forming member H1600 is fixed to the tank holder H1500 for detachably holding the ink tank H1900 by, for example, ultrasonic welding, and an ink flow path H1501 extending from the ink tank H1900 to the first plate H1200 is formed. Has formed. In addition, a filter H1700 is provided at the ink tank side end of the ink flow path H1501 that engages with the ink tank H1900, so that dust can be prevented from entering from the outside. In addition, a seal rubber H1800 is attached to an engagement portion with the ink tank H1900, so that evaporation of ink from the engagement portion can be prevented.

Further, as described above, the tank holder H15
00, a tank holder portion composed of a flow path forming member H1600, a filter H1700, and a seal rubber H1800, a printed element substrate H1100, a first plate H
1200, an electric wiring board H1300, and a print element section composed of a second plate H1400 are bonded to each other by an adhesive or the like, thereby forming a print head H1001.
Is composed.

2.2 Carriage Next, the carriage M4001 on which the head cartridge H1000 is mounted will be described with reference to FIG.

As shown in FIG. 2, the carriage M4001
The print head H1001 to the carriage M400
1, a carriage cover M4002 for guiding to a predetermined mounting position on the print head H1001, and a head set lever M4007 which engages with the tank holder H1500 of the print head H1001 and presses the print head H1001 to the predetermined mounting position. ing.

That is, the head set lever M4007 as the attaching / detaching means of the present invention is provided on the upper part of the carriage M4001 so as to be rotatable with respect to the head set lever shaft, and the engaging portion with the print head H1001 is provided with a spring. A headset plate (not shown) is provided, and a print head H1001 is provided by this spring force.
And is mounted on the carriage M4001 while pressing.

Further, a contact flexible print cable (see FIG. 7; hereinafter, referred to as a contact F) is provided on another engagement portion of the carriage M4001 with the print head H1001.
E0011 is provided and a contact FPC is provided.
Contact part on E0011 and print head H10
01 (external signal input terminal) H
1301 makes electrical contact with each other so that various kinds of information for printing can be transferred and power can be supplied to the print head H1001.

Here, an elastic member such as rubber (not shown) is provided between the contact portion of the contact FPC E0011 and the carriage M4001, and the contact portion is formed by the elastic force of the elastic member and the pressing force of the headset lever spring. The secure contact with the carriage M4001 is enabled. Further contact FPCE0
Reference numeral 011 is connected to a carriage substrate E0013 mounted on the back of the carriage M4001 (see FIG. 7).

3. Scanner The printer in this embodiment can also be used as a reading device by mounting a scanner on the carriage M4001 instead of the above-described head cartridge H1000.

This scanner moves in the main scanning direction together with the carriage M4001 on the printer side, and reads a document image fed instead of a print medium in the course of movement in the main scanning direction. By alternately performing a reading operation along the main scanning direction and a document feeding operation along the sub-scanning direction, one document image information can be read.

FIGS. 6A and 6B show this scanner M6.
000, a scanner M6000
FIG.

As shown, the scanner holder M6001
Has a substantially box-like shape, and contains therein an optical system and a processing circuit necessary for reading. When the scanner M6000 is mounted on the carriage M4001, a reading unit lens M600 is provided at a portion facing the original surface.
The lens M6006 is used to read the document image by focusing the document surface on an internal reading unit. On the other hand, the illumination unit lens M6005
Has a light source (not shown) inside, and the light emitted from the light source is applied to the document via a lens M6005.

The scanner cover M6003 fixed to the bottom of the scanner holder M6001 is attached to the scanner holder M6.
The inside of 001 is fitted so as to shield light, and the operability of attaching and detaching to and from the carriage M4001 is improved by louver-shaped grips provided on the side surface. Scanner holder M60
01 has substantially the same outer shape as the print head H1001, and can be attached to and detached from the carriage M4001 by the same operation as the head cartridge H1000.

The scanner holder M6001 houses a substrate having a read processing circuit, and a scanner contact PCB connected to the substrate is provided so as to be exposed to the outside. The scanner M6000 is mounted on the carriage M4001. Scanner contact PCB when attached
M6004 is a contact F on the carriage M4001 side.
The substrate is brought into contact with the PC E0011 and the carriage M40
01 is electrically connected to a control system on the main body side.

4. Next, an electric circuit configuration according to the embodiment of the present invention will be described.

FIG. 7 is a diagram schematically showing an overall configuration example of an electric circuit in this embodiment.

The electric circuit in this embodiment mainly includes a carriage board (CRPCB) E0013 and a main PCB.
(P rinted C ircuit B oard) E0014, and is configured by including a power supply unit E0015.

Here, the power supply unit E0015 is connected to the main PCB E0014 and supplies various drive powers.

The carriage board E0013 is a printed circuit board unit mounted on the carriage M4001 (FIG. 2). The carriage board E0013 functions as an interface for transmitting and receiving signals to and from the print head H1001 through the contact FPC E0011. , A change in the positional relationship between the encoder scale E0005 and the encoder sensor E0004 is detected based on the pulse signal output from the encoder sensor E0004, and the output signal is converted to a flexible flat cable (C
RFFC) Main PCB E001 through E0012
4 is output.

[0056] Further, the main PCB E0014 is a printed circuit board unit that controls driving of each unit of the ink jet printing apparatus in this embodiment, a paper end sensor (PE sensor) E0007, an automatic sheet feeding (A utomatic
S heet F eeder: hereinafter referred to as ASF) sensor E00
09, cover sensor E0022, parallel interface (parallel I / F) E0016, serial interface (serial I / F) E0017, resume key E
0019, LED E0020, power key E0018,
An I / O port for the buzzer E0021 and the like is provided on the board. Further, a motor (CR motor) E000 serving as a drive source for causing the carriage M4001 to perform main scanning.
1, a motor (LF motor) E0002 serving as a drive source for transporting a print medium, a print head H1001
(PG motor) E0003 which is used for both the recovery operation of the printer and the feeding operation of the print medium to control the driving of these motors.
GAP sensor E0008, PG sensor E0010, CRFFC E0012, power supply unit E for detecting the gap between print head H1001 and print medium
0015.

FIG. 8 is a block diagram showing the internal configuration of the main PCB E0014.

In the figure, E1001 is a CPU,
The CPU E1001 has a clock generator (CG) E1002 connected to the oscillation circuit E1005 therein, and generates a system clock by an output signal E1019. In addition, R through the control bus E1014
OM E1004 and ASIC (A pplication S pecif
It is connected to the ic I ntegrated C ircuit) E1006, RO
ASIC E10 according to the program stored in M
06, the input signal E1017 from the power key, the input signal E1016 from the resume key, the cover detection signal E1042, the head detection signal (HSENS) E10
13 is detected, and a buzzer signal (BUZ)
The buzzer E0021 is driven by E1018 to detect the state of the ink empty signal (INKS) E1011 connected to the built-in A / D converter E1003 and the state of the temperature detection signal (TH) E1012 by the thermistor. It determines the conditions and controls the driving of the inkjet printing apparatus.

Here, the head detection signal E1013 is a head mounting detection signal input from the head cartridge H1000 via the flexible flat cable E0012, the carriage board E0013, and the contact flexible print cable E0011, and the ink empty detection signal E1011 is the ink empty detection signal E1011. An analog signal and a temperature detection signal E1012 output from the empty sensor E0006 are analog signals from a thermistor (not shown) provided on the carriage substrate E0013.

E1008 is a CR motor driver which uses a motor power supply (VM) E1040 as a drive source and
CR motor control signal E1036 from IC E1006
Generates a CR motor drive signal E1037 according to
The R motor E0001 is driven. E1009 is LF / P
A G motor driver that uses a motor power supply E1040 as a drive source, generates an LF motor drive signal E1035 according to a pulse motor control signal (PM control signal) E1033 from the ASIC E1006, and thereby drives the LF motor and the PG motor A drive signal E1034 is generated to drive the PG motor.

E1010 is a power supply control circuit,
In accordance with a power control signal E1024 from CE1006, power supply to each sensor having a light emitting element is controlled. Parallel I / F E0016 is ASIC E10
, A parallel I / F signal E1030 from the external device 06 is transmitted to a parallel I / F cable E1031 connected to the outside,
Also, the signal of the parallel I / F cable E1031 is converted to ASI
It transmits to CE1006. Serial I / F E001
7 transmits the serial I / F signal E1028 from the ASIC E1006 to the serial I / F cable E1029 connected to the outside, and transmits the signal from the cable E1029 to the ASIC E1006.

On the other hand, from the power supply unit E0015, a head power supply (VH) E1039 and a motor power supply (VM)
E1040, a logic power supply (VDD) E1041 is supplied. Also, the head power ON signal (VHON) E1022 from the ASIC E1006 and the motor power ON
The signal (VMOM) E1023 is connected to the power supply unit E0015.
To control ON / OFF of the head power supply E1039 and the motor power supply E1040, respectively. Logic power (VDD) supplied from power supply unit E0015
E1041 is supplied to various parts inside and outside the main PCB E0014 after voltage conversion as necessary.

The head power signal E1039 is sent to the flexible flat cable E0011 after being smoothed on the main PCB E0014, and is used for driving the head cartridge H1000.

E1007 is a reset circuit which detects a drop in the logic power supply voltage E1041 and outputs a reset signal to the CPU E1007.
1 and the ASIC E1006 output a reset signal (RES
ET) Supply E1015 to perform initialization.

The ASIC E1006 is a one-chip semiconductor integrated circuit.
U1001 and outputs the above-described CR motor control signal E1036, PM control signal E1033, power control signal E1024, head power ON signal E1022, motor power ON signal E1023, etc., and outputs the parallel I / F E0016 and serial I / F. E001
7 and a PE detection signal (PES) E1025 from the PE sensor E0007, and an ASF sensor E
ASF detection signal (ASFS) E102 from 0009
6, a GAP detection signal (G
APS) PG from E1027, PG sensor E0010
The state of the detection signal (PGS) E1032 is detected, and data representing the state is sent to the CPU via the control bus E1014.
E1001 and CPU based on the input data
E1001 controls the drive of the LED drive signal E1038 to blink LEDE0020.

Further, the encoder signal (ENC) E10
A timing signal is generated by detecting the state of No. 20 and a print operation is controlled by interfacing with the head cartridge H1000 using the head control signal E1021. Here, the encoder signal (ENC) E1020 is an output signal of the CR encoder sensor E0004 input through the flexible flat cable E0012.
The head control signal E1021 is supplied to the print head H1001 via the flexible flat cable E0012, the carriage board E0013, and the contact FPC E0011.

FIG. 9 is a block diagram showing an example of the internal configuration of the ASIC E1006.

In the figure, the connection between the blocks is described in terms of print data and motor control data.
Only the flow of data related to the control of the heads and mechanical components of each part is shown. Control signals related to reading and writing of registers built in each block, clocks, control signals related to DMA control, and the like are complicated in the drawings. Omitted for avoidance.

In the figure, reference numeral E2002 denotes a PLL controller. As shown in FIG. 9, an ASIC E is provided by a clock signal (CLK) E2031 and a PLL control signal (PLLON) E2033 output from the CPU E1001.
A clock (not shown) to be supplied to most of the inside 1006 is generated.

E2001 is a CPU interface (CPU I / F), and reset signals E1015, C10
Soft reset signal (PDWN) E2032 output from PU E1001, clock signal (CLK) E2
031 and control signals from the control bus E1014, control of register read / write for each block as described below, supply of a clock to some blocks, acceptance of an interrupt signal, and the like (both not shown) are performed. An interrupt signal (INT) E2034 is output to the CPU E1001, and the ASIC E1006 is output.
Notifies the occurrence of an internal interrupt.

Reference numeral E2005 denotes a DRAM, which is a reception buffer E201 as a data buffer for printing.
0, work buffer E2011, print buffer E2
014, each area such as a development data buffer E2016, a motor control buffer E2023 for motor control, and a buffer used in the scanner operation mode, which is used in place of the print data buffer described above. Scanner capture buffer E20
24, a scanner data buffer E2026, and a transmission buffer E2028.

The DRAM E2005 has a CP
It is also used as a work area necessary for the operation of the EU 1001. That is, E2004 is a DRAM control unit, which is provided from the CPU E1001 by the control bus to the DRAM control unit.
Access to E2005 and DMA control unit E described later
Switching from access to the DRAM E2005 from 2003 is performed to perform a read / write operation to the DRAM E2005.

The DMA controller E2003 receives a request (not shown) from each block, and receives an address signal and a control signal (not shown), and in the case of a write operation, write data E2038, E2041, E2044, and E2.
053, E2055, E2057 and the like are output to the DRAM control unit E2004 to perform DRAM access. In the case of reading, the read data E2040, E2043, E2045, E2045 from the DRAM control unit E2004 are read.
2051, E2054, E2056, E2058, E2
059 is passed to the requesting block.

Further, E2006 is based on IEEE1284I /
F and CPU via CPU I / FE 2001
The parallel I / F E0016 is controlled by the control of E1001.
, A bidirectional communication interface with an external host device (not shown), and a parallel I / F at the time of printing.
Received data from E0016 (PIF received data E2
036) is transferred to the reception control unit E2008 by DMA processing.
05 (1284 transmission data (RDPIF) E2059) stored in the transmission buffer E2028 in
It is transmitted to the parallel I / F by MA processing.

[0075] E2007 is USB (U niversal S erial B
us) I / F and C via CPU I / FE 2001
Under the control of the PUE 1001, the serial I / F E00
17, a bidirectional communication interface with an external host device (not shown) is provided, and a serial I / F
Received data from E0017 (USB received data E2
037) is transferred to the reception control unit E2008 by DMA processing, and the DRAM E2005 is read at the time of scanner reading.
(US) stored in the sending buffer E2028
B transmission data (RDUSB) E2058) is transmitted to the serial I / F E0017 by DMA processing. The reception control unit E2008 writes the reception data (WDIF) E2038 from the selected I / F of the 1284 I / FE2006 or the USB I / FE 2007 into the reception buffer write address managed by the reception buffer control unit E2039.

Reference numeral E2009 denotes a compression / decompression DMA controller which controls the CPU via the CPU I / F E2001.
Under the control of E1001, the reception data (raster data) stored in the reception buffer E2010 is read from the reception buffer read address managed by the reception buffer control unit E2039, and the data (RDWK) E204.
0 is compressed / expanded in accordance with the designated mode, and written as a print code string (WDWK) E2041 in the work buffer area.

E2013 is a print buffer transfer DMA
In the controller, C via CPU I / FE 2001
Work buffer E20 under the control of PU E1007
11 is read, and each print code is read from the head cartridge H10.
00 and rearranged to an address on the print buffer E2014 suitable for the data transfer order (WDWP).
E2044). E2012 is a work clear DMA controller, and CPU I / F E2001
The designated work fill data (WDWF) E2042 is repeatedly written into the area on the work buffer to which the transfer by the print buffer transfer DMA controller E2013 is completed under the control of the CPU E1001 via the CPU.

Reference numeral E2015 denotes a print data development DMA controller, which is a C controller via the CPU I / FE 2001.
The head control unit E201 is controlled by the PU E1001.
8 is used as a trigger to read out the print codes rearranged and written on the print buffer and the data for expansion written on the data buffer for expansion E2016, and develop print data (RDHDG). E2045 as column buffer write data (WDHDG) E2047
Write to 2017. Here, the column buffer E2017
Is an SRAM for temporarily storing transfer data (developed print data) to the head cartridge H1000, and a print data developed DMA controller E2015
It is shared and managed by both blocks by a handshake signal (not shown) between the two blocks.

E2018 denotes a head control unit which controls the CPU I /
Under the control of the CPU E1001 via the FE2001, the head cartridge H10 is controlled via a head control signal.
00 or an interface with the scanner, and print data development DMA based on a head drive timing signal E2049 from the encoder signal processing unit E2019.
Data expansion timing signal E20 for the controller
Output 50.

At the time of printing, the developed print data (RDHD) E2048 is read from the column buffer in accordance with the head drive timing signal E2049, and the data is output to the head cartridge H1000 as a head control signal E1021.

In the scanner reading mode, the fetched data (WDHD) E2053 input as the head control signal E1021 is transferred to the DRAM E2005.
The data is DMA-transferred to the upper scanner fetch buffer E2024. E2025 is a scanner data processing DMA controller, which is a CPU via a CPU I / F E2001.
The scanner capture buffer E2 is controlled by the control of E1001.
024 stored in the capture buffer (R
DAV) E2054 is read, and processed data (WDAV) E2055, which has been subjected to averaging and the like, is stored in a DRAM.
Write to the scanner data buffer E2026 on E2005.

E2027 is a scanner data compression DMA controller, which is a CP via the CPU I / F E2001.
Under the control of the U E1001, the processed data (RDYC) E2056 on the scanner data buffer E2026 is read out to perform data compression, and the compressed data (WDYC)
E2057 is written and transferred to the sending buffer E2028.

E2019 is an encoder signal processing unit, which receives an encoder signal (ENC) and receives a signal from the CPU E1.
In addition to outputting the head drive timing signal E2049 in accordance with the mode determined by the control of 001, information relating to the position and speed of the carriage M4001 obtained from the encoder signal E1020 is stored in a register.
1001. The CPU E1001 determines various parameters in controlling the CR motor E0001 based on this information. E2020 denotes a CR motor control unit, which is a CPU via a CPU I / F E2001.
By the control of E1001, the CR motor control signal E103
6 is output.

Reference numeral E2022 denotes a sensor signal processing unit which detects signals E1032, E1024, and E102 output from the PG sensor E0010, the PE sensor E0007, the ASF sensor E0009, the GAP sensor E0008, and the like.
6, E1027, and based on the mode determined by the control of the CPU E1001, these sensor information are
001, and a sensor detection signal E205 to the LF / PG motor control DMA controller E2021.
2 is output.

The DMA controller E2021 for controlling the LF / PG motor is connected to the CPU controller E2021 via the CPU I / F E2001.
The DRAM E2005 is controlled by the PU E1001.
In addition to reading the pulse motor drive table (RDPM) E2051 from the upper motor control buffer E2023 and outputting the pulse motor control signal E1033, depending on the operation mode, the pulse motor control signal E1033 is output using the sensor detection signal as a control trigger.

E2030 is an LED control unit.
CPU E1001 via CPU I / F E2001
, An LED drive signal E1038 is output.
Further, E2029 is a port control unit, and CPUI /
Under the control of the CPU E1001 via the FE2001, a head power ON signal E1022, a motor power ON signal E1023, and a power control signal E1024 are output.

5. Next, the operation of the inkjet printing apparatus according to the embodiment of the present invention configured as described above will be described with reference to the flowchart of FIG.

When the apparatus main body 1000 is connected to the AC power supply, first, in step S1, first initialization processing of the apparatus is performed. In this initialization process, the ROM and RA
An electric circuit system check such as a check of M is performed to confirm whether the present device can be normally operated electrically.

Next, in step S2, the apparatus main body M100
0 power key E001 provided on the upper case M1002.
8 is turned on, and the power key E00
If the button 18 has been pressed, the process moves to the next step S3, where a second initialization process is performed.

In the second initialization processing, various drive mechanisms of the apparatus and the print head H1001 are checked. That is, when the various motors are initialized and the head information is read, it is confirmed whether the apparatus can operate normally.

Next, in step S4, an event is waited. That is, the apparatus monitors command events from the external I / F, panel key events due to user operations, internal control events, and the like, and executes a process corresponding to the event when these events occur.

For example, if a print command event is received from the external I / F in step S4, the process proceeds to step S5, and if a power key event is generated by a user operation in the same step, the process proceeds to step S10. The process proceeds to step S11 when another event occurs in the same step.

Here, in step S5, a print command from the external I / F is analyzed to determine the designated paper type, paper size, print quality, paper feeding method, and the like. Stored in the RAM E2005 in the device,
Proceed to step S6.

Next, in step S6, paper feeding is started by the paper feeding method designated in step S5, the paper is fed to the print start position, and the flow advances to step S7.

At step S7, a printing operation is performed. In this printing operation, the print data sent from the external I / F is temporarily stored in a print buffer, and then the CR motor E0001 is driven to drive the carriage M400.
1 starts moving in the main scanning direction, and the print data stored in the print buffer E2014 is supplied to the print head H1001 to print one line, and the print operation of one line of print data ends. Then, the LF motor E0002 is driven, and the LF roller M30 is driven.
01 is rotated to feed the paper in the sub-scanning direction. After this,
The above operation is repeatedly performed, and when printing of one page of print data from the external I / F is completed, the process proceeds to step S8.

In step S8, the LF motor E0002
Is driven to drive the paper discharge roller M2003, and the paper feeding is repeated until it is determined that the paper is completely fed out of the apparatus. When the paper is completely discharged, the paper is completely discharged onto the paper discharge tray M1004a. Becomes

Next, in step S9, it is determined whether or not the printing operation of all the pages to be printed has been completed. If the pages to be printed remain, the process returns to step S5. The operations from S5 to S9 are repeated, and when the printing operation for all pages to be printed is completed, the printing operation is completed. Then, the process proceeds to step S4 to wait for the next event.

On the other hand, in step S10, a printer termination process is performed, and the operation of this apparatus is stopped. That is, in order to turn off the power of various motors and heads, the state is shifted to a state where the power can be turned off, then the power is turned off, and the process proceeds to step S4 to wait for the next event.

In step S11, other event processing other than the above is performed. For example, a process corresponding to a recovery command from various panel keys of this apparatus or an external I / F, a recovery event generated internally, and the like are performed. After the process is completed, the process proceeds to step S4 and waits for the next event.

6. Print Head Here, the configuration and arrangement of the ejection port group of the print head H1001 used in this embodiment will be described.

Print head H100 in this embodiment
FIG. 11 shows a fracture structure of the first printed element substrate H1100, and FIG.
These are shown in FIGS. 14 and 15, respectively. Printed circuit board H1
Numeral 100 denotes a structure in which a discharge energy generating section, a liquid chamber, a discharge port, and the like are formed on a silicon substrate 11 having a thickness of 0.5 mm to 1 mm by using a film forming technique.

The silicon substrate 11 has an elongated liquid supply port 12 penetrating therethrough. On both sides of the liquid supply port 12, a plurality of lines (128 in one side in this embodiment) are arranged at predetermined intervals along the longitudinal direction of the liquid supply port 12.
) Are formed in a state shifted from each other by a half pitch, and constitute an ejection energy generating unit. On the silicon substrate 11, in addition to the electrothermal converters 13, electrode terminals 14 for making an electrical connection between the electrothermal converter 13 and the printer main body, and electric wiring (not shown) formed of aluminum or the like are formed. A drive I (not shown) is formed through the electrode terminals 14 by a film technique.
A drive signal for the electrothermal converter 13 is given from C,
At the same time, drive power is supplied to the electrothermal converter 13.

The liquid supply port 12 is provided on the silicon substrate 11.
An upper plate member 17 having a plurality of discharge ports 16 respectively facing the electrothermal converter 13 via a liquid chamber 15 communicating with the electrothermal converter 13 is formed. That is, a liquid flow path 18 communicating with the liquid supply port 12 and the individual liquid chambers 15 is formed between the upper plate member 17 and the silicon substrate 11, and these are formed by the photolithography technique similarly to the discharge port 16. It is formed together with the upper plate member 17.

The liquid supplied from the liquid supply port 12 into each of the liquid chambers 15 is supplied with a drive signal to the corresponding electrothermal converter 13 in the liquid chamber 15, thereby generating heat from the electrothermal converter 13. The liquid is boiled, and is discharged from the discharge port 16 by the pressure of the generated bubble. In this case, the liquid chamber 15
The air bubbles generated in the air flow from the discharge port 16 to the atmosphere as the air bubbles grow.

FIG. 12 shows the arrangement of the electrothermal converter 13 and the discharge ports 16 in this embodiment.
13, 14, and 15 show cross-sectional structures taken along arrows I, XIV-XIV, and XV-XV, respectively. Discharge port 15 in two rows
Is 1200 dpi, and the distance between the centers of the electrothermal transducers 13 adjacent to each other in the arrangement direction is set to 21 μm. As is clear from FIG. 12, the distance from the opening end of the liquid supply port 12 to each electrothermal converter 13 is set to a different distance in consideration of time-division driving. The electrothermal converters 13 all have the same dimensions and are square with a side of 24 μm. Discharge port 16
Also have the same dimensions, are squares each having a side of 16 μm, and each have a length L of 12 μm (see FIG. 14). The height H (see FIG. 14) of the liquid chamber 15 is 13 μm, and the ejection amount of the ink droplet ejected from the ejection port 13 by one driving of the electrothermal converter 13 is set to 5 picoliter. .

The shape of the discharge port 16 may be rectangular, round or star-shaped in addition to the square as in this embodiment.

The displacement amount α of the axis C of the discharge port 16 with respect to the axis R (hereinafter simply referred to as the axis) passing through the center position of the electrothermal transducer 13 and the position of the ink droplets reaching the print medium due to this. FIG. 16 shows the relationship with the shift amount β. In FIG. 16, the plus sign of the coordinate indicates that the axis C of the ejection port 16 and the position of the ink droplet attached to the print medium are deviated to the right with respect to the axis R of the electrothermal transducer 13 in FIG. In FIG. 12, the minus coordinate indicates that the axis C of the ejection port 16 and the position of the ink droplet adhering to the print medium are offset to the left with respect to the axis R of the electrothermal converter 13. As is clear from FIG. 16, even if the deviation amount α between the axis R of the electrothermal transducer 13 and the axis C of the ejection port 16 is about several micrometers, the position of the ink droplet adhering to the print medium, that is, the deviation amount .beta. can be shifted by several tens of micrometers, and the larger the shift .alpha. between the axis R of the electrothermal transducer 13 and the axis C of the discharge port 16, the larger the shift .beta. of the position of the ink droplet adhering to the print medium. can do. By utilizing this phenomenon, the positions of the ejection ports 16 located at both ends in the arrangement direction are shifted with respect to the axis R of the corresponding electrothermal transducer 13, thereby controlling the ejection direction of ink droplets ejected from the axis. It becomes possible.

In this embodiment, the axis R of the four electrothermal converters 13a located at both ends along the direction in which the discharge ports 16 are arranged is set.
On the other hand, the axis C of each of the discharge ports 16a is shifted by 1 μm in a direction away from the center in the arrangement direction (see FIGS. 13 and 15), and the axes C of the four electrothermal converters 13b adjacent to these are respectively shifted. Axis C of the discharge port 16b
0.5 in the direction away from the center in the arrangement direction.
It is shifted by μm. The axis R of all the other electrothermal transducers 13 and the axis C of the discharge port 16 are shown in FIG.
Are set coaxially as shown in FIG. In any case, when solid printing is performed with the axis R of the electrothermal transducer 13 and the axis C of the ejection port 16 aligned, the amount of deviation of ink droplets ejected from both ends in the arrangement direction of the ejection port 16 It is necessary to set the amount of displacement of the corresponding discharge port 16 in accordance with

Therefore, when a drive pulse is applied to the eight electrothermal transducers 13a and 13b located at both ends along the arrangement direction of the discharge ports 16, these discharge ports 16a and 16b
The ink droplets ejected from the b are formed on the axis R of the electrothermal transducers 13a and 13b in accordance with the direction of displacement of the ejection ports 16a and 16b.
Is ejected in an inclined state with respect to the discharge port 16, but is pulled back toward the center in the arrangement direction of the discharge ports 16 by the reduced pressure atmosphere near the discharge port surface 19 where the discharge ports 16 are opened, and finally reaches the intended position of the print medium. I do. Other than this, the axis R of the electrothermal transducer 13 and the axis C of the discharge port 16 are not displaced, so that the liquid is discharged straight along the axis C of the discharge port 16.

While the ink jet print head H1001 is moved along with the carriage M4001 at high speed along the print medium, ink droplets are continuously discharged from all the discharge ports 16, so-called solid printing is performed on the print medium. FIG. 17 shows the ink droplet ejection state at this time. Print head H10
The scanning movement direction 01 is a direction perpendicular to the paper surface of FIG. 17, and the ejection openings (not shown) are arranged in the left-right direction in the figure. Therefore, even when a solid print is formed on the print medium 20, in the present embodiment, the ejection port 1 is used.
Electrothermal transducers 1 located at both ends along the arrangement direction of
Since the ejection ports 16a and 16b corresponding to 3a and 13b are shifted to the outside, ink droplets ejected from the ejection ports 16a and 16b are ejected while being inclined outward. However, the discharge port surface 1
9, these ink droplets are drawn toward the center side and finally reach the intended position of the print medium 20, so that the ink droplets are conventionally generated each time the carriage M4001 scans. It is possible to prevent the occurrence of white streaks and the like that have been occurring.

In the above-described embodiment, the electrothermal transducers 13 are formed at regular intervals, and the arrangement intervals of the discharge ports 16 are different between the center and the end. However, the discharge ports 16 are formed at regular intervals. Then, the arrangement interval of the electrothermal transducers 13 may be different between the center and the end. In this case, it is effective that the axis R of the electrothermal transducer 13 is formed closer to the center in the arrangement direction with respect to the axis C of the ejection ports 16 at the ends along the arrangement direction of the ejection ports 16.

The present invention includes a means (for example, an electrothermal converter or a laser beam) for generating thermal energy as the energy used for discharging the liquid. The present invention brings about an excellent effect in an ink jet type liquid ejection head, a head cartridge, or an image forming apparatus which causes a change. According to such a method, it is possible to achieve higher density and higher definition of the print.

The typical structure and principle are described in, for example, US Pat. No. 4,723,129 and US Pat.
It is preferable to use the basic principle disclosed in Japanese Patent Application No. 0796. This method can be applied to both the so-called on-demand type and the continuous type. In particular, in the case of the on-demand type, it is arranged corresponding to the sheet or the flow path holding the liquid. Heat energy is generated by applying at least one drive signal to the electrothermal transducer to give a rapid temperature rise exceeding nucleate boiling corresponding to print information, thereby causing film boiling on the heat working surface of the liquid discharge head. As a result, bubbles in the liquid corresponding to this drive signal one-to-one can be formed, which is effective. By the growth and shrinkage of the bubble, the liquid is discharged through the discharge port 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 the liquid having particularly excellent responsiveness can be achieved, which is more preferable. 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 U.S. Pat. No. 4,313,124 relating to the rate of temperature rise of the heat acting surface are adopted, more excellent printing can be performed.

Further, as a configuration of the liquid discharge head, a combination configuration of the discharge port, the liquid path, and the electrothermal converter as disclosed in the above-mentioned respective specifications (the electrothermal converter is arranged along the liquid path) U.S. Pat. No. 6,059,055 discloses a configuration in which a disposed linear liquid flow path or an electrothermal converter is disposed in a region where a heat acting portion is bent in addition to a liquid flow path and a right-angled liquid flow path directly facing the discharge port. Patent No. 4558333 and US Patent No. 44596
The configuration using the specification of No. 00 is also included in the present invention. In addition, JP-A-59-123670 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 a pressure wave of thermal energy is provided. A configuration based on JP-A-59-138461, which discloses a configuration corresponding to a discharge unit,
The effects of the present invention are effective. That is, according to the present invention, printing can be performed reliably and efficiently regardless of the form of the liquid discharge head.

Further, even in the case of the serial type as in the above-described embodiment, the liquid ejecting head is integrally fixed to the carriage that moves for scanning, or is exchangeably mounted on the carriage so that the carriage and the carriage can be replaced. A replaceable chip-in type liquid ejection head which enables electrical connection of the liquid and supply of liquid from the apparatus main body, or a head cartridge provided with a tank for storing liquid integrally with the liquid ejection head itself is used. Even in such a case, the present invention is effective.

As a configuration of the image forming apparatus of the present invention, the addition of recovery means for making the state of liquid discharge from the liquid discharge head proper, preliminary auxiliary means, and the like further stabilizes the effects of the present invention. It is preferable because it can be performed.
Specific examples thereof include a capping unit for the liquid ejection head, a cleaning unit, a pressurizing or suctioning unit, a preheating unit for heating using an electrothermal transducer, another heating element, or a combination thereof. ,
Preliminary ejection means for performing ejection separately from the printing operation can be used.

The type and number of mounted liquid ejection heads are, for example, not only one provided corresponding to a single color ink, but also a plurality of types provided with different print colors and densities (brightness). A plurality may be provided corresponding to the ink. That is, for example, the print mode of the image forming apparatus is not limited to a print mode of only a mainstream color such as black, and may be either an integrated liquid discharge head or a combination of a plurality of liquid discharge heads. The present invention is extremely effective also in an apparatus provided with at least one of the print modes of full-color by color or mixed color. In this case, it is also effective to discharge a processing liquid (printability improving liquid) for adjusting the printability of the ink to the print medium from a dedicated or common liquid discharge head according to the type of print medium and the print mode.

Further, in the above-described embodiments of the present invention, a material which solidifies at room temperature or lower and softens or liquefies at room temperature may be used. In general, the temperature is adjusted within the range described above to control the temperature so that the viscosity of the liquid is in the stable ejection range. Therefore, a liquid that is in a liquid state when the used print signal is applied may be used. In addition, in order to positively prevent the temperature rise due to thermal energy by using it as the energy of the state change from the solid state to the liquid state, or to prevent the liquid from evaporating, it is solidified in a standing state and liquefied by heating May be used.
In any case, the liquid is liquefied by the application of the thermal energy according to the print signal, and is liquefied only by the application of the thermal energy, such as the one from which the liquid is ejected and the one which already starts to solidify when reaching the print medium. The present invention can be applied to the case of using a material having a property. The liquid in such a case is, as described in JP-A-54-56847 or JP-A-60-71260, in a state where it is held as a liquid or solid substance in the concave portion or through hole of the porous sheet. Alternatively, it may be configured to face the electrothermal converter. In the present invention, the most effective one for each of the above-mentioned liquids is to execute the above-mentioned film boiling method.

The form of the image forming apparatus according to the present invention can be used not only as an image output terminal of an information processing apparatus such as a computer, but also as a copying apparatus combined with a reader or the like, as well as a facsimile apparatus having a transmission / reception function. The printing medium may be in the form of a printing device. The printing medium may be a sheet or long paper or cloth, or a plate or wood, stone, resin, glass, metal, or the like, or may be three-dimensional. Examples include three-dimensional structures.

[0120]

According to the present invention, the amount of displacement between the axis of the discharge port and the corresponding center position of the discharge energy generating portion is determined by the central portion and the end of the discharge port along the arrangement direction. Since the directions of the ejection are different, the axes of the ejection ports located at both ends are aligned with the ejection energy generating section so that the ejection direction of the droplets ejected from the ejection ports located at both ends in the arrangement direction is away from the center in the arrangement direction. By shifting the position of the droplet to the center of the print medium, the position of the droplet that finally reaches the print medium can be corrected to the expected position, and high definition and high gradation without white streaks even when performing solid printing High quality print image can be obtained. In particular, when the present invention is applied to a so-called bubble-through type in which bubbles grown by film boiling communicate with the atmosphere via a discharge port, the following applies.
The number of droplets ejected from the ejection port is reduced to 10 picoliters or less and the high-definition, high-gradation, high-quality print image can be obtained by performing the rotation.

[Brief description of the drawings]

FIG. 1 is a perspective view illustrating an external configuration of an inkjet printer according to an embodiment of the present invention.

FIG. 2 is a perspective view showing a state where an exterior member of the printer shown in FIG. 1 is removed.

FIG. 3 is a perspective view showing an assembled state of a head cartridge used in a printer according to an embodiment of the present invention.

4 is an exploded perspective view showing the head cartridge shown in FIG.

FIG. 5 is an exploded perspective view of the print head shown in FIG. 4 as viewed obliquely from below.

FIG. 6 is a perspective view showing a configuration of a scanner cartridge which can be mounted on a printer according to an embodiment of the present invention in an inverted manner instead of the head cartridge shown in FIG. 3;

FIG. 7 is a block diagram schematically showing an overall configuration of an electric circuit in the printer of one embodiment of the present invention.

8 is a block diagram showing an example of an internal configuration of a main PCB of the electric circuit shown in FIG. 7;

FIG. 9 is a block diagram showing an example of the internal configuration of an ASIC in the main PCB shown in FIG. 8;

FIG. 10 is a flowchart illustrating an operation of the printer according to the embodiment of the present invention.

FIG. 11 is a cutaway perspective view of a part of a print element substrate constituting a part of a head cartridge according to an embodiment of the present invention.

FIG. 12 is a conceptual diagram schematically showing an arrangement pattern of ejection ports formed on the print element substrate shown in FIG.

FIG. 13 is a sectional view taken along the arrow XIII-XIII in FIG.

14 is a sectional view taken along the line XIV-XIV in FIG.

FIG. 15 is a sectional view taken along the line XV-XV in FIG. 12;

FIG. 16 is a graph showing the relationship between the amount of displacement of the position of the discharge port with respect to the electrothermal transducer and the position at which ink droplets adhere to the print medium.

FIG. 17 is a conceptual diagram schematically illustrating an ink ejection state of a head cartridge according to an embodiment of the present invention.

FIG. 18 is a conceptual diagram schematically illustrating a state of ink ejection by a conventional inkjet printer.

FIG. 19 is a conceptual diagram schematically showing a solid image formed on a print medium by the ink ejection mode shown in FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 11 Silicon substrate 12 Liquid supply port 13 Electrothermal converter 14 Electrode terminal 15 Liquid chamber 16 Discharge port 17 Upper plate member 18 Liquid flow path 19 Discharge port surface 20 Print medium α Displacement amount of discharge port relative to electrothermal converter β Print medium Amount of displacement of ink droplet adhering to ink L Length of ejection port H Height of liquid chamber R Axis passing through center position of electrothermal transducer C Axis of ejection port P Print sheet M1000 Machine body M1001 Lower case M1002 Upper case M1003 Access Cover M1004 Ejection tray M1004a, M1004b Auxiliary tray M2003 Ejection roller M3001 LF roller M3019 Chassis M3022 Automatic feeding unit M3029 Transport unit M3030 Ejection unit M4000 Print unit M4001 Carriage M4002 Carriage cover M4007 Headset Bar (detachment means) M4021 Carriage shaft M5000 Recovery system unit M6000 Scanner M6001 Scanner holder M6003 Scanner cover M6004 Scanner contact PCB M6005 Illumination lens M6006 Reading lens E0001 Carriage motor E0002 LF motor E0003 PG motor E0004 Encoder encoder E0005 Encoder scale E0005 Encoder scale Sensor E0007 PE sensor E0008 GAP sensor E0009 ASF sensor E0010 PG sensor E0011 Contact FPC (flexible print cable) E0012 CRFFC (flexible flat cable) E0013 Carriage board E0014 Main board E0015 Power supply unit E0016 Para I / F E0017 Serial I / F E0018 Power key E0019 Resume key E0020 LED E0021 Buzzer E0022 Cover sensor E1001 CPU E1002 OSC (Oscillator with built-in CPU) E1003 A / D (A / D converter with built-in CPU) E1004 ROM E1005 Oscillator circuit E1006 ASIC E1007 Reset circuit E1008 CR motor driver E1009 LF / PG motor driver E1010 Power supply control circuit E1011 INKS (ink end detection signal) E1012 TH (thermistor temperature detection signal) E1013 HSENS (head detection signal) E1014 control bus E1015 RESET (reset signal) E10 RESUME (Resume key input) E1017 POWER (Power key Input) E1018 BUZ (Buzzer signal) E1019 Oscillator circuit output signal E1020 ENC (Encoder signal) E1021 Head control signal E1022 VHON (Head power ON signal) E1023 VMON (Motor power ON signal) E1024 Power control signal E1025 PES (PE detection signal) E1026 ASFS (ASF detection signal) E1027 GAPS (GAP detection signal) E0028 Serial I / F signal E1029 Serial I / F cable E1030 Parallel I / F signal E1031 Parallel I / F cable E1032 PGS (PG detection signal) E1033 PM control signal ( Pulse motor control signal) E1034 PG motor drive signal E1035 LF motor drive signal E1036 CR motor control signal E1037 CR motor drive signal E 038 LED drive signal E1039 VH (head power supply) E1040 VM (motor power supply) E1041 VDD (logic power supply) E1042 COVS (cover detection signal) E2001 CPU I / F E2002 PLL E2003 DMA control unit E2004 DRAM control unit E2005 DRAM EE128 DRAM FE2007 USB I / F E2008 Reception control unit E2009 Compression / expansion DMA controller E2010 Reception buffer E2011 Work buffer E2012 Work area DMA controller E2013 Print buffer transfer DMA controller E2014 Print buffer E2015 Print data expansion DMA controller E2016 Expansion data buffer E2017 Column buffer E2018 Head Control unit E2019 Encoder signal processing unit E2020 CR motor control unit E2021 LF / PG motor control unit E2022 Sensor signal processing unit E2023 Motor control buffer E2020 Scanner capture buffer E2020 Scanner data processing DMA controller E2026 Scanner data buffer E2027 Scanner data compression DMA controller E2028 Sending Buffer E2029 Port control unit E2030 LED control unit E2031 CLK (clock signal) E2032 PDWM (soft control signal) E2033 PLLON (PLL control signal) E2034 INT (interrupt signal) E2036 PIF reception data E2037 USB reception data E2038 WDIF (reception data / raster Data) E2039 Receive buffer controller E2 40 RDWK (reception buffer read data /
Raster data) E2041 WDWK (work buffer write data /
Print code) E2042 WDWF (work fill data) E2043 RDWP (work buffer read data / print code) E2044 WDWP (reorder print code) E2045 RHDDG (print development data) E2047 WHDDG (column buffer write data / expansion print data) E2048 RDHD (column buffer read data / developed print data) E2049 Head drive timing signal E2050 Data develop timing signal E2051 RDPM (pulse motor drive table read data) E2052 Sensor detection signal E2053 WDHD (captured data) E2054 RDAV (capture buffer read data) E2055 WDAV (data buffer write data /
E2056 RDYC (data buffer read data / processed data) E2057 WDYC (transmission buffer write data / compressed data) E2058 RDUSB (USB transmission data / compression data) E2059 RDPIF (1284 transmission data) H1000 head cartridge H1001 print head H1100 Print element substrate H1100T Discharge port H1200 First plate H1201 Ink supply port H1300 Electric wiring board H1301 External signal input terminal H1400 Second plate H1500 Tank holder H1501 Ink flow path H1600 Flow path forming member H1700 Filter H1800 Seal rubber H1900 Ink tank H1901 Removal lever

Claims (14)

[Claims] A plurality of discharge ports arranged along a transport direction of a print medium; and a plurality of discharge energy generating units disposed opposite to the discharge ports to discharge liquid from the discharge ports. A liquid ejection head that scans and moves along the print medium in a direction that intersects with the transport direction of the print medium, wherein an axis of the ejection port and a central position of the ejection energy generation unit corresponding thereto. A liquid ejecting head characterized in that the amount of deviation from the center differs from the center portion along the arrangement direction of the ejection ports and the end thereof. 2. The method according to claim 1, wherein the amount of the displacement is a size along an arrangement direction of the discharge ports, and the amount of the displacement at a central portion along the arrangement direction is zero. 3. The liquid ejection head according to item 1. 3. The displacement at an end portion along the arrangement direction is such that an axis of a discharge port is formed in a direction away from a central portion along the arrangement direction with respect to a center position of a discharge energy generating portion. The liquid discharge head according to claim 2, wherein: 4. The discharge energy generating portion according to claim 1, wherein the discharge energy generating portions are formed at regular intervals, and the arrangement intervals of the discharge ports are different between a central portion and an end portion. The liquid discharge head according to any one of the above. 5. The discharge port according to claim 1, wherein the discharge ports are formed at a constant interval, and an arrangement interval of the discharge energy generating portions is different between a central portion and an end portion. The liquid discharge head according to any one of the above. 6. The apparatus according to claim 1, wherein the discharge energy generating section includes an electrothermal converter that generates thermal energy for causing the liquid to discharge from the discharge port by causing film boiling of the liquid. A liquid ejection head according to claim 5. 7. The liquid discharge head according to claim 6, wherein bubbles that grow by film boiling communicate with the atmosphere via the discharge port. 8. The method according to claim 8, wherein the ejection energy generating unit is driven once to reduce the amount of droplets ejected from the ejection port by one.
8. The liquid discharge head according to claim 1, wherein the liquid discharge head is equal to or less than 0 picoliter. 9. A head cartridge, comprising: the liquid ejection head according to claim 1; and a liquid tank for storing a liquid supplied to the liquid ejection head. 10. The head cartridge according to claim 9, wherein the liquid tank is detachable from the liquid ejection head via attachment / detachment means. 11. A printing medium, comprising: a mounting portion for a liquid ejection head according to claim 1; and means for transporting a printing medium, wherein the printing medium is ejected from an ejection port of the liquid ejection head. An image forming apparatus for forming an image on an image. 12. The image forming apparatus according to claim 11, wherein the attachment unit has a carriage that can scan and move in a direction that intersects a direction in which the print medium is conveyed. 13. The image forming apparatus according to claim 12, wherein the liquid discharge head is detachably mounted on the carriage via a detachable unit. 14. The liquid according to claim 11, wherein the liquid is a processing liquid for adjusting printability of the ink and / or the ink on a print medium.
The image forming apparatus according to any one of the above.