JP3241183B2 - Ink jet recording device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet recording apparatus for performing recording by discharging ink onto a recording medium.

[0002]

2. Description of the Related Art An ink jet recording apparatus performs recording by discharging ink from a discharge port provided in a recording means (recording head) onto a recording medium such as paper, and it is easy to make the recording means compact. It can record high-definition images at high speed, can record on plain paper without special processing, has low running cost, and has low noise due to non-impact method, and it can print It has advantages such as easy recording of a color image using ink. In particular, ink jet recording means (recording head) by a method of vaporizing and foaming ink using thermal energy and discharging the ink with the energy of the foaming is used on a substrate through a semiconductor manufacturing process such as etching, vapor deposition, and sputtering. By forming an electrothermal transducer, an electrode, a liquid path wall, a top plate, and the like formed on the substrate, a high-density liquid path arrangement (discharge port arrangement) can be easily manufactured. Compactness can be achieved.

[0003] An ink jet recording apparatus is generally provided with an ejection recovery device in order to eliminate clogging of an ejection port due to drying, and a problem that causes ejection failure of ink such as dust and air bubbles. The main function of this ejection recovery device is to cover the ejection port forming surface including the ejection port with a cap made of an elastic material such as rubber, and to suck and decompress the air in the cap with a pump or the like to eject ink. The above problem is solved by forcibly discharging the ink.

On the other hand, in recent years, RGB (R; red, G; green,
B; blue) or YMC (Y; yellow, M; magenta, C;
The demand for color printing using a color such as cyan) is increasing, and the number of models that perform color printing in an inkjet recording apparatus is also increasing. In an ink jet recording apparatus capable of recording in color, an ink jet recording head is prepared for each color, and recording is performed while exchanging these recording heads or simultaneously mounting a plurality of types of recording heads on the recording apparatus. It has become.
However, in such an ink jet recording apparatus,
When the ejection recovery processing is performed on the recording unit that ejects color ink, the ink remaining in the cap or the waste ink remaining in the ink flow path when suction is performed is conversely placed in the ejection port on the recording unit side. There was invasion. Even if the amount of ink that enters at this time is very small,
For example, when a dark color ink such as a black ink is mixed with a light ink such as a yellow ink, it gives a considerable visual discomfort.In particular, when outputting an image, an original color tone cannot be reproduced. Problems sometimes occurred.

Further, such a problem does not necessarily occur only in the case of an ink jet recording head using a color ink. For example, even if the same color ink is used in a recording head having a different specification, the composition of the ink used is different. When these recording heads are used at the same time or exchanged, it is necessary to avoid mixing inks.

In order to avoid the problem of ink mixing in the discharge ports, it is possible to provide a plurality of discharge recovery devices and assign a dedicated discharge recovery device one for each color. In the case of the configuration, it is inevitable that the size and cost of the recording apparatus increase, and it is difficult to realize such a configuration particularly in a personal type recording apparatus. As another method, there is a countermeasure such that a predetermined number of inks are always ejected from an ejection port immediately before printing to eject a mixed color component. However, even in the method of discharging a fixed number of shots, it is necessary to provide a receiving portion or a storing portion for the discharged ink, and it is inevitable that the device becomes larger and the cost increases.

Furthermore, a dedicated storage box is prepared for the recording means of each color for each color, and the recording means is stored in the storage box, or a discharge recovery device is provided in each of the storage boxes, There is a method in which the recovery process is always performed by the dedicated discharge recovery device.

[0008]

However, if a storage box is prepared even for a frequently used ink, for example, a black ink, the operability is inevitably reduced, which is not practical. Also,
Although it is conceivable to provide only an ejection recovery device corresponding to a recording head that is frequently used in the recording device, the user performs an erroneous operation to perform ejection recovery processing for recording heads of other colors using this ejection recovery device. In such a case, the above-described inconvenience may occur. In order to prevent printing failure due to drying and fixing of ink, the recording apparatus may be provided with a means for performing an automatic ejection recovery process at predetermined time intervals by, for example, timer management. The ejection recovery process is performed irrespective of the precautions described above, and the above-described problem occurs.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an ink jet recording apparatus capable of avoiding deterioration of image quality due to mixing of ink between different recording heads.

[0010]

According to a first aspect of the present invention, there is provided an ink jet recording apparatus using recording means for discharging ink onto a recording medium, a cap for covering a discharge port forming surface of the recording means, and a cap inside the cap. An ink-jet device comprising: a suction device for performing a suction process of applying ink to the recording device by applying a suction force to the recording medium; and a discharge / discharge device for performing a discharge / discharge process of discharging ink to a portion other than the recording medium. In the recording apparatus, when a recording unit corresponding to a plurality of recording units and performing the suction process is defined as a first recording unit, and a recording unit that has performed the suction process immediately before is defined as a second recording unit, wherein the said suction punished Lima other according to the combination of the discharge and the type of ink and the type of discharging ink of said second recording means in the first recording means pair to the discharge discharge process Control operation is change that.

[0011]

According to a second aspect of the present invention, there is provided an ink jet recording apparatus.
Using a recording unit that ejects ink onto a recording medium, executing a suction process of applying a suction force to the inside of the cap to cover the ejection port forming surface of the recording unit and sucking ink from the recording unit. An ink jet recording apparatus having a suction unit for performing ink discharge and a discharge and discharge process for discharging ink onto a medium other than the recording medium, wherein an identification unit for identifying a type of ink discharged by the recording unit; A storage unit for storing the type of ink, and reading the ink type of the recording unit that has performed the suction process immediately before by referring to the storage unit, and identifying the read ink type and the identification unit by the identification unit. The suction process for the recording means according to the combination with the type of ink.
Lima et a control means for storing performs control of the discharge discharge process, the type of ink identified by said identifying means in the storage means.

[0013]

Since the ejection recovery sequence is changed according to the color and composition of the ink ejected by the recording means and the processing history of the ejection recovery processing device, it is possible to mix the ink between different recording heads and execute the minimum necessary ejection recovery process. It can be prevented by the number of times. Thereby, it is possible to prevent a problem due to ink mixing without increasing the consumption of ink, and
Deterioration such as an increase in the size of the apparatus due to an increase in the size of the waste ink tank and the effect on durability can be minimized, and good printing can always be obtained.

[0014]

Next, embodiments of the present invention will be described with reference to the drawings.

Embodiment 1 FIG. 1 is a perspective view showing the structure of an ink jet recording apparatus according to Embodiment 1 of the present invention. This ink jet recording apparatus is compatible with monocolor (monochromatic) recording, that is, it can only record one color at a time, but can record any color by replacing the ink jet recording head.

In this ink jet recording apparatus, a cartridge type recording means in which an ink jet recording head and an ink tank are integrated, that is, a head cartridge 9 is used. The head cartridge 9 is removably mounted on a carriage 11 for performing main scanning in the direction of arrow S in the figure. Various types of head cartridges 9 are prepared according to the ink colors. The carriage 11 has a regulating plate 12 used when attaching and detaching the head cartridge 9, and the head cartridge 9 is attached to the carriage 1.
A hook 13 for attaching the hook 1 and a lever 15 for operating the hook 13 are provided. Lever 15
A marker 17 is provided for indicating a scale provided on a cover, which will be described later, so that the print position and set position of the recording head of the head cartridge can be read. Further, the carriage 11 is provided with a support plate 19 that supports an electrical connection to the ink head cartridge 9, and the electrical connection and the main body control unit are connected by a flexible cable 21.

The carriage 11 is guided in the S direction in the figure by a guide shaft 23 inserted through a bearing 25 of the carriage 11. A timing belt 27 for moving the carriage 11 in the S direction is provided. The timing belt 27 is attached to the carriage 11, and pulleys 29A,
It is stretched on 29B. The driving force is transmitted to one pulley 29B from the carriage motor 31 via a transmission mechanism such as a gear.

Recording medium such as paper (hereinafter also referred to as recording paper)
A plantain roller 33 is provided for regulating the recording surface and transporting the same during recording or the like. The platen roller 33 is driven by a transport motor 35. Further, there are provided a paper pan 37 for guiding the recording medium to the recording position, and a feed roller 39 which is disposed in the middle of the recording medium feeding path and presses the recording medium toward the plantain roller 33 to convey the recording medium. Have been. A discharge roller 41 for discharging the recording medium toward a discharge port (not shown) is disposed upstream in the recording medium transport direction and downstream from the recording position. A spur 42 is provided corresponding to the paper discharge roller 41, thereby pressing the roller 41 through the recording medium and causing the paper discharge roller 41 to generate a conveyance force of the recording medium. A release lever 43 is provided to release the urging of each of the feed roller 39, the pressing plate 45, and the spur 42 when setting a recording medium or the like.

A pressing plate 45 is provided for suppressing the floating of the recording medium in the vicinity of the recording position and for ensuring the close contact with the platen roller 33. In this embodiment, since the ink jet recording system is employed as the recording means, the distance between the ink ejection port forming surface of the head cartridge 9 and the recording surface of the recording medium is relatively small, and the recording device The arrangement of the presser plate 45 is effective because the interval between them must be strictly controlled in order to avoid contact with the discharge port forming surface. A scale 47 is provided on the holding plate 45, and a marker 49 is attached to the carriage 11 corresponding to the scale 47. With these, the print position and the set position of the head cartridge 9 can be read.

A cap 51 corresponding to the home position of the carriage 11 faces the ejection port forming surface of the head cartridge (recording head) 9 where the ink ejection ports are formed.
Are arranged. The cap 51 is formed of a rubber-like elastic material, and is supported so as to be able to come into contact with and detach from the discharge port forming surface. The cap 51 is used for protecting the recording head (discharge port forming surface) at the time of non-recording or the like and for recovering the recording head from ejection. In the ejection recovery process, the ink is ejected from all the ejection openings by driving the energy generation element provided inside the ink ejection openings and used for ink ejection, with the cap 51 facing the ejection opening formation surface. This allows air bubbles and dust,
Preliminary ejection processing for removing the cause of ejection failure such as ink that has become unsuitable for recording due to thickening, or separately forcibly ejecting ink from the ejection ports while covering the ejection port formation surface and the cap 51 This is a process for removing the cause of ejection failure.

A pump 53 used for the discharge recovery process is provided. The pump 53 applies a suction force for forcibly discharging ink, and discharge recovery processing by the forced discharge and discharge recovery by preliminary discharge. It is used to suck ink received by the cap 51 during processing. A waste ink tank 55 for storing the waste ink sucked by the pump 53 is provided, and the pump 53 and the waste ink tank 55 are connected by a tube 57. Further, a motor 61 for driving the discharge recovery system and a cam device 63 for receiving power from the motor 61 to drive the pump 53 and move the cap 51 are provided.

Next, the configuration of the head cartridge 9 will be described. FIG. 2 is a perspective view of the monocolor ink head cartridge viewed from below. 2, the head cartridge 9 has a structure in which an ejection unit 9a, which is a main body of a recording unit (recording head), and an ink tank 9b are integrated.

The head cartridge 9 is provided with a claw 906e that is hooked on a hook 13 provided on the carriage 11 when the head cartridge 9 is mounted. Have been. A positioning abutment (not shown) is provided in the vicinity of the ejection unit 9 a on the front side of the head cartridge 9. An opening 906f into which the support plate 19 erected on the carriage 11 is inserted is provided on the bottom surface. The support plate 19 is for supporting the electrical connection portion (a flexible substrate described later) and the rubber pad as described above.

The head cartridge 9 is of a disposable type, and different types are prepared for each color of ink. And head cartridge 9
Includes an ink color identification ID (not shown) corresponding to each color.
Is provided at a contact portion with a flexible substrate described later. The ink color identification ID has an electrically detectable configuration, and is formed here by appropriately cutting the print pattern of the printed circuit board. As a result, the discharge unit 9a and the tank section (ink tank 9
b) and the like can be configured by common components independent of the ink color.

FIG. 3A is an exploded perspective view of the head cartridge 9 of FIG. 2, and FIG. 3B is an external perspective view of the head cartridge 9 as viewed from the front. is there. In FIG. 3A showing each component of the discharge unit 9a, a heater board 911 includes an electrothermal conversion element (discharge heater) and a wiring made of aluminum or the like for supplying power thereto on a silicon (Si) substrate. The structure is formed by a film forming technique. A wiring board 921 for the heater board 911 is provided, and the corresponding wiring is connected by, for example, wire bonding. Base plate 930 also serving as heat sink
Is made of aluminum or the like.

The top plate 940 is provided with a partition for limiting the ink flow path, a common liquid chamber, and the like. Here, the top plate 940 is formed of a resin material integrally having a discharge port plate portion.

The ink is supplied from an ink tank 9b serving as an ink supply source, and a heater board 911 and a top plate 940 are provided.
A sub-tank 960 is provided for guiding ink to a common liquid chamber formed by joining with the ink tank. A filter 970 is provided at a position in the sub tank 960 near the ink supply port to the common liquid chamber. Sub tank 96
0 is provided with a lid member 980.

An absorber 900 for impregnating ink is arranged in the main body of the ink tank 9b. A supply port 1200 for supplying ink to the ejection unit (recording element) 9a is provided. In a step before the ejection unit 9a is arranged in the portion 1010 of the main body of the ink tank 9b, ink is supplied from the supply port 1200. The ink can be impregnated into the absorber 900 by being injected. Further, the head cartridge 9 is provided with a lid member 1100 of its main body, and the lid member 1100 is provided with an atmosphere communication port 1300 for communicating with the atmosphere inside the head cartridge 9.

The ink in the ink tank 9b is supplied to the supply port 1
200, hole 932 provided in support body 930, sub tank 9
The sub-tank 96 is provided through an inlet provided on the back side of the sub-tank 96.
It is supplied within 0. The ink in the sub tank 960 flows into the common liquid chamber from the outlet through an appropriate supply pipe and the ink outlet 942 of the top plate 940. A packing such as silicon rubber or butyl rubber is provided at the connection portion for ink communication as described above, whereby sealing is performed and an ink supply path is secured.

FIG. 4 is a perspective view of the top plate 940. As shown in the figure, the ejection port forming surface 221 on the top plate 940 is inclined by a predetermined angle θ with respect to a plane parallel to the recording surface of the recording medium (recording paper), and at a portion near the ejection port 222. In order to process the discharge port by irradiating a laser beam, a flow path in the discharge port plate portion 940a and a flow path behind the flow path are arranged at a predetermined angle.

FIG. 5 shows a discharge unit (recording head) 9a.
FIG. 4 is a partial perspective view schematically illustrating the structure of an ink ejection unit of FIG. A predetermined gap (for example, about 0.5 to
Discharge port forming surface 221 facing at a distance of about 2.0 mm)
Has a plurality of discharge ports 222 formed at a predetermined pitch,
Each liquid path 2 communicating the common liquid chamber 223 and each discharge port 222
An electrothermal converter (heat generating resistor or the like) 225 for generating energy for ink ejection is disposed along the wall surface of 24. In this embodiment, the discharge unit 9a
Are mounted on the carriage 11 in such a positional relationship that the discharge ports 222 are arranged in a direction intersecting the moving direction (main scanning direction) of the carriage 11. In this manner, the corresponding electrothermal transducer 225 is driven (energized) based on the image signal or the ejection signal to cause the ink in the liquid path 224 to boil, and the ink is ejected from the ejection port 222 by the pressure generated at that time. It has become.

FIG. 6 is an exploded perspective view showing the structure of the ejection recovery device including the cap 51, the pump 53, the motor 61, the cam device 63, and the like in the ink jet recording apparatus of FIG. In FIG. 2, an ink absorber 501 is arranged inside a cap 51. A holding member 503 for holding the cap 51 and a cap lever 505 rotatably mounted on a pin 507 are provided. The cap lever 505 has a function of causing the cap 51 to abut / remove the ejection port forming surface 221 of the head cartridge 9 by a force applied to the pin 507. Further, a pin 51 for engaging with the end 509 of the cap lever 505 to restrict the rotation range of the cap lever 505 is provided.
1 is provided.

In FIG. 6, the cap lever 505
The jig 513 having a hole into which the pin 507 is fitted is
Supporting part 51 provided with cap lever 505 on pump 53
Used to attach to 5. A fastening member 516 for securing this attachment state is used. Acting portion 51 for applying a force to a cap 51 to come into contact with a discharge port forming surface
7 engages substantially at the center of the rear portion of the cap 51. The action section 517 has an introduction port 517A (see FIG. 7C) for introducing the sucked ink. Also, the inside of the cap lever 505, the inside of the pin 507, the jig 513
An ink flow path for guiding the sucked ink is formed inside the support section 515 and inside the support section 515. When the pump 53 exerts a suction force, the ink sucked from the discharge port 222 is introduced into the pump 53 from the introduction port 517A through each ink flow path as indicated by an arrow in the drawing.

A shaft 519 projecting from the center of the end face of the pump 53 and having an ink flow path therein is rotatably attached to the side wall 520 . When the pump 53 itself rotates, its rotational displacement is transmitted to the cap lever 50 via the support 515.
5, the cap 51 moves forward and backward with respect to the discharge port forming surface 221 by the displacement of the cap lever 505. A flow path forming member 521 connected to the pump shaft 519 and a mounting member 523 for mounting the tube 57 leading to the waste ink tank 55 (FIG. 1) are provided. That is, an ink flow path is formed inside each of the pump shaft 519, the flow path forming member 521, and the mounting member 523, and the ink sucked by the pump 53 passes through these ink flow paths as shown by arrows in the drawing. The waste ink tank 55 is guided and further passed through a tube 57 (FIG. 1).
Is introduced to

The pump 53 includes a piston 525, a piston shaft 527 which is a shaft of the piston 525, a packing 529,
It is composed of a cap 531. A pin 533 is attached to the piston shaft 527, and the pin 533 has a function of receiving a driving force for operating the piston 525. Further, a spring 5 that gives the pump 53 itself a turning behavior in which the cap 53 moves toward the recording head 9 side.
39 and a gear train 541 for transmitting the rotation of the motor 61 to the cam device 63. The cam device 63 engages with an engaging portion 545 provided on the pump 53 to rotate the cam 547 and a pin 533 provided on a piston shaft 527 of the pump 53 to operate the pump. And a cam 557 that engages with a switch 555 for detecting the home position of the cam device 63. The operation of these cams will be described later.

7A to 7C are views showing details of the cap 51, FIG. 7A is a front view, FIG. 7B is a plan view, and FIG.
FIG. 8C is a cross-sectional view taken along line C in FIG. In these figures, an ink suction port 561 is opened in a vertically lower portion of the cap 51, and the ink suction port 561 communicates with an ink introduction port 517 </ b> A provided in the action section 517 of the cap lever 505 through an ink flow path 563. are doing.
Further, the ink absorber 501 in the cap 51 is arranged so as not to completely cover the ink suction port 561.
As a result, even if the ink flows downward due to gravity, the ink is sucked through the ink suction port 561 provided below, so that the amount of ink remaining in the ink absorber 501 is significantly reduced. Can be greatly delayed to extend the life of the ink absorber 501 or the cap 51 to which the ink absorber 501 is attached.

Next, the operation of the recovery system unit, that is, the discharge recovery device in this embodiment will be described. Here, there are four types of head cartridges 9 mounted on the ink jet recording apparatus, and these ink colors are black (Bk), yellow (Y), magenta (M), and cyan (C), respectively. FIG. 8 is a cam chart of the recovery device 63. The horizontal axis indicates the rotation angle of the cam 549, and the switch 5
The state of 55, cap 51, pump 53, and blade 59 is shown. FIG. 9 is a diagram showing the position of the piston 525 in the pump 53 in each state. FIG. 10 compares the density of the ink ejected from the ink cartridge targeted for the ejection recovery processing with the density of the ink ejected from the ink cartridge that has just executed the ejection recovery processing based on Table 1 described below. 9 is a flowchart illustrating an “optimum process determination routine” for performing an optimal ejection recovery process according to the result. FIG. 11 is a flowchart showing the control contents of the “ejection recovery processing” in the optimum processing determination routine shown in the state (e) of FIG. FIG. 12 is a flowchart showing the control contents of the idle suction operation during printing.

Table 1 shows the difference between the color density of the ink ejected by each of the four types of head cartridges that can be mounted on the ink jet recording apparatus and the density difference between the other three types of ink as the order of the density. is there. That is, the order difference is shown according to the combination of the color for which the previous ejection recovery processing was performed and the color for which the ejection recovery processing is to be performed. In addition,
The difference in the order of shading in this table is not necessarily based on the optical density, and the numerical value of the order difference is increased as the risk of lowering the print quality increases when a certain color is mixed. When there is no risk of deteriorating the print quality, it is defined as 1.

[0039]

[Table 1] In FIG. 8, the state (a) is a state where the cam 549 is at the home position and printing is being performed, and the ejection recovery device is in a standby state. The switch 555 is turned on, the cap 51 is separated from the head discharge port forming surface (hereinafter referred to as an open state), and the pump 53 is at the top dead center. Also, the blade 59
Is retracted to an off state, that is, a position where it does not engage with the head.

The state (b) following this is a capping state, which is a state where the ink jet recording apparatus is not used, and the cap 51 covers and protects the head discharge port forming surface. . The switch 555 is off, the cap 51 is joined to the head discharge port forming surface (closed state), the pump 53 is at the top dead center, and the blade 59
Is off.

The state (c) is a state where the pumping is completed. The switch 555 is on, the cap 51 is closed, and the pump 53 is in a state where the valve is fully opened, and is in a state where it does not reach the bottom dead center. The blade 59 is off.

In the state (d), after the pumping is completed, the cap 51 is opened, and at the same time, the ink filled in the cap 51 and the cap lever 505 is supplied to the pump 5.
This is a state in which the execution of the suction of the small air for taking in the inside 3 has been completed. The switch 555 is on, the cap 51 is about half open, the pump 53 is at bottom dead center, and the blade 59 is off.

Subsequently, the state of (e), the state of (f), and then the state of (g) will be described.
Will be described first. In the state of (g), the ink filled in the pump 53 by pumping is
This is a preparation state to start idle suction for discharging to the 5th side.
The switch 555 is on, the cap 51 is open, and the pump 53 is slightly below the top dead center. The blade 59 is off.

Here, the states of (e) and (f) are the states at the stop position when the air suction and the hollow suction are performed, respectively. In any state, the switch 555
Is on, the cap 51 is open, and the blade 59 is off, but the state of the pump 53 is on the bottom dead center side in (e), but is not completely lowered in (f).

The state (h) subsequent to the state (g) is a state when wiping is performed. The switch 555 is on, the cap 51 is open, and the pump 53 is at the top dead center. Then, the blade 59 is in the ON state, and in this state, the carriage 11 on which the head cartridge 9 is mounted moves to perform wiping of the head discharge port forming surface.

Here, regarding the actual movement of the pump 53,
This will be described with reference to FIGS.

FIG. 9A shows a state in which the piston 525 is located at the bottom dead center in the pump 53. Pump 53
Pumping is performed by the negative pressure created by the space to the left of piston 525 in the inner space. The valve port 531 is for transmitting the negative pressure to the cap 51. In the state shown in FIG. 9A, it can be seen that the piston 525 has passed over the valve port 531 and has further advanced to the right. Here, since the piston 525 is pressed from the left side by the flange portion 527 of the piston shaft and is in close contact therewith, the generated negative pressure is transmitted to the cap 51 side without leaking. The ink accumulated on the right side of the piston shaft 525 is pushed out to the waste ink tank 55.

FIG. 9B shows a state where the pump 53 is at the top dead center. It should be noted here that the piston 525 is
31 and the valve port 531 is not closed. That is, in this state, the cap 51 is in an air communication state.

FIG. 9C shows the state of the pump 53 at the time of (c) in FIG. The piston 525 is the valve port 53
Going over 1 and going slightly to the right.

FIG. 9 (D) shows the state at the time of (g) in FIG. 8. By reciprocating between this state and the state of FIG. 9 (A) or FIG. Performing hollow suction.

FIG. 9E shows a state where the hollow suction has been completed. It should be noted here that the piston 525 stops immediately after having passed over the valve port 531. If the piston 525 reaches the bottom dead center (see FIG. 9A), when returning to the top dead center (see FIG. 9B) or the idle suction preparation position (FIG. 9D), the valve port is closed. The time during which the 531 is not closed can be lengthened. At this time, the piston shaft flange 52 should be
7a and the piston 525 have a slight gap.
It is configured so as to communicate with the space on the right side of 25. However, a slight positive pressure is generated due to the resistance of the flow path or the like, so that a reverse flow occurs. When returning from the position shown in FIG. 9 (E) to the position shown in FIG. 9 (A) or FIG. 9 (D), the backflow is well prevented.

Next, the operation of this embodiment will be described with reference to the flowchart of FIG.

The ejection recovery process is started when the user manually issues an ejection recovery command, or when a timer described later exceeds a predetermined time and a printing command is issued. The timer is reset to 0 by the execution of the ejection recovery process and restarts counting as described later. The main purpose of the execution of the ejection recovery process by the timer management is to fix the ink in the ejection port or to remove bubbles or the like generated between the tank and the ejection port, which cause the ejection failure of the ink.

First, it is determined whether or not the number of idle suctions performed so far from the previous ejection recovery operation has exceeded 10 times (step 801). d is set to 1 (step 805),
Proceed to step 806. The reason for setting d = 1 here is that if the idle suction operation is performed more than 10 times, the influence of the difference in the ink color due to the replacement of the ink cartridge is almost eliminated.

If the number of idle suctions is determined to be 10 or less as determined in step 801, the electrical ID and the flexible substrate are used to change the color of the ink that can be recorded by the ink cartridge targeted for the ejection recovery process. A determination is made (step 802). On the other hand, the color of the ink ejected from the ink cartridge that has been subjected to the previous ejection recovery processing is stored in the EEPROM for storing the ink color. The color to be discharged from the cartridge is obtained (step 803). Then, from the ink color of the ink cartridge to be subjected to the previous ejection recovery process and the ink color of the ink cartridge to be subjected to the current time, a density order difference d is obtained from Table 1 described above (step 804), and step 8 is performed.
Proceed to 06.

In step 806, d obtained in step 804 or 805 is substituted for N. Then, the ejection recovery process described in detail later with reference to FIG. 11 is executed (step 807), and 1 is subtracted from N to determine whether N has become 0 (step 808). For example, the flow returns to step 807 to execute the ejection recovery processing again. N =
If it is 0, the process proceeds to step 809. That is, the ejection recovery process of step 807 is executed d times.

In step 809, the memory for counting the number of times of idle suction is reset, and thereafter, the color of the ink which has been subjected to the ejection recovery processing this time is written in the memory (EEPROM) for storing the ink color (step 810).
The process ends.

Next, the details of the ejection recovery processing in step 807 will be described with reference to the flowchart of FIG.

The ejection recovery process starts from the capping state shown in the state of FIG. 8B (step 821).
Then, by moving to the state (c), pumping for ink suction is executed (step 822). In this state, a stop for 3 seconds is performed so that the ink suction is sufficiently performed (step 823). Then, the state shifts to the state shown in FIG. 8D, suction of small air is performed simultaneously with opening of the cap (step 824), and ink is taken in the cap 51 and the cap lever 505. In this state, a stop for one second is performed (step 825). Subsequently, in order to remove the other color ink that has entered the ejection port by the suction, preliminary ejection is performed for each ejection port at a number of times 100 times the rank difference d (step 826).

Next, in order to discharge the ink filled in the pump 53, the operation shifts to the idle suction operation. First, the head is set to the blade-off state, and the head is moved to the idle suction preparation position shown in FIG. 8G (step 827), and the idle suction preparation operation is performed (step 828), and N = 3 (step 829). Then, the process moves to the hollow suction stop position shown by (f) in FIG. 8 to perform hollow suction (step 830), stops for 0.3 seconds (step 831), and performs an idle suction preparation operation (step 83).
2). It is determined whether N becomes 0 by subtracting 1 from N (step 833). If N ≠ 0, the process returns to step 830 to execute hollow suction again. If N = 0, the process proceeds to step 834. In other words, by executing steps 830 to 833, reciprocation is performed three times from the empty suction position to the hollow suction stop position.

In step 834, the sky suction shown in (g) to (e) of FIG. 8 is performed, and the operation is stopped for 0.3 seconds (step 835). This allows the pump 53
The ink inside is sufficiently pushed out to the waste ink tank 55 side. Subsequently, the head moves to the position (g) to perform the preliminary ejection (step 836), and then moves the head to the blade-on position (step 837). The blade is turned on at the position (h) in FIG. 8 (step 838), and wiping is executed by moving the head to the blade off position (step 839). Finally, the blade is turned off at the position (a) (step 840), the head is returned to the capping position (step 841), and capping is performed in the state of (b) (step 842), and the ejection recovery processing is completed.

In the recording apparatus according to the present embodiment, the cap opening time including the time during ink ejection is set to 3 in order to prevent printing defects due to drying of the ink in the ink ejection ports.
When the time exceeds 0 second, 100 preliminary discharges are performed in the cap 51 for each of all the discharge ports. Therefore, when the amount of ink ejected by the preliminary ejection increases,
If the cap 51 exceeds the ink receiving capacity of the cap 51,
And the ink overflows, and stains the inside of the recording apparatus. Therefore, in this recording apparatus, every time a certain number of preliminary ejections controlled according to the cap opening time reach a certain number of times,
The idle suction is performed, and the ink in the cap 51 is sent to the waste ink tank 55. Here, the idle suction operation will be described with reference to the flowchart of FIG.

First, the cap is opened (step 8).
51), preparation for empty suction is performed (step 852), and hollow suction is performed (step 853). In this state, the operation is stopped for 0.3 seconds (step 854), the empty suction preparation is performed again (step 855), and the large air suction is performed (step 85).
6). Then, the operation is stopped for 0.3 seconds in this state (step 85).
7) The cap is opened (step 858), and the idle suction operation ends.

FIG. 13 is a block diagram showing a configuration example of a control system of an ink jet recording apparatus to which the present invention is applied.
This recording apparatus is provided with a recovery home sensor 65 and a carrier home sensor 67 for detecting whether the carriage 11 is at a capping position or a moving position.
Also, the head cartridge 9, the carriage motor 31,
A head driver 9A for driving the transport motor 35 and the recovery motor 61, and motor drivers 31A and 3 respectively.
5A and 61A are provided. The control system receives the detection results from these sensors 65 and 67, and receives each driver 9A, 3
1A, 35A, and 61A, an MPU 1000 for controlling each unit, a ROM 1001 storing a program corresponding to a control procedure, and a RAM 100 used as a work area when executing the control procedure.
2. It is composed of a timer 1003 for measuring time and an interface unit 1004. A keyboard 1 is connected to the control system.
Command data and recording data can be input from the computer.

<< Embodiment 2 >> Instead of the optimal control selection flow in Embodiment 1 (see FIG. 10), control may be performed according to a flowchart shown in FIG. In FIG. 14, steps denoted by the same step numbers as in FIG. 10 are steps for performing the same operations as those shown in FIG. That is, after performing the same operations as in steps 801 to 806 in FIG. 10, no preliminary ejection is issued (step 861), and the idle suction as shown in FIG. 12 is executed (step 862). It is determined whether N becomes 0 by subtracting 1 from N (step 863). If N ≠ 0, the flow returns to step 831 to execute the preliminary ejection and the idle suction again. If N = 0, go to step 864.

In step 864, the ejection recovery process shown in FIG. 11 is performed. Thereafter, the memory for counting the number of times of idle suction is reset (step 809), and the current ejection recovery is performed in the memory (EEPROM) for storing the ink color. The color of the processed ink is written (step 81
0), and the process ends.

After all, according to the present embodiment, before performing the ejection recovery processing, the idle suction is performed the same number of times as the ink density order difference d, and the unnecessary waste ink in the cap and the ink flow path is removed from the waste ink tank. To prevent mixing with the remaining different kinds of ink.

[0068]

[0069]

Third Embodiment In the first embodiment, the number of ejections is changed according to the difference d in the order of density. However, the number of ejections is not always required. For example, the longitudinal movement of the piston provided in the discharge recovery processing device is controlled by a motor, a gear train, a cam, etc. provided separately from the discharge recovery motor, and the suction amount is changed by changing the stroke during suction, When the density order difference d is large, the suction amount may be increased. According to this, the same effect as that of the first embodiment can be obtained, and the ejection recovery processing is completed in a shorter time than in the case of the first embodiment.

Fourth Embodiment In each of the above-described embodiments, the description has been given of the control of the ejection recovery processing performed automatically by a user's instruction or timer management. However, the present invention is not necessarily applied only under the above conditions. Not something. For example, if a certain amount of ink remains in the cap due to the ejection recovery process or pre-ejection during printing, if the head is replaced, etc., an ink cartridge that ejects ink different from this remaining ink Capping by the cap is performed, and ink mixing may occur.

Therefore, when capping is performed on a recording head that ejects ink different from the recording head that has been capped up to that time, the ejection recovery processing or idle suction is performed by the control described in detail in each of the above embodiments. May be performed. FIG. 15 is a flowchart showing the control in this case. It is determined whether or not head replacement has been performed (step 881). If replacement has been performed, an optimal ejection recovery processing selection routine is executed (step 882).
Regardless of whether or not the head has been replaced, the process returns to step 881 to determine the replacement. As a result, the different kinds of ink remaining in the cap are removed, and it is possible to prevent the different kinds of ink from entering the recording head.

<< Other Embodiments >> The present invention is not always effective only for the above-described color ink cartridges. For example, the present invention is applicable to inks having different ink compositions such as cotton dyeing and polyester dyeing. Applicable. Further, the present invention is not limited to a recording apparatus in which only one ink cartridge can be mounted at the same time, but is also applicable to, for example, a full-color recording apparatus in which a plurality of types of ink cartridges can be mounted at the same time.

The content stored in the memory does not necessarily have to be the color or composition of the ink in the ink cartridge to be subjected to the ejection recovery process. For example, all ink types that can be stored in the recording apparatus are ranked. Alternatively, this order may be stored. Further, the number of times of the ejection recovery processing, the number of times of idle suction, the timing of performing the processing, and the like do not necessarily have to follow the above-described embodiments. Good.

In each of the embodiments described above, a disposable type recording head has been mainly described. However, the present invention is not necessarily limited to this, and the present invention can be applied to a permanent type recording head.

The present invention provides an excellent effect particularly in a recording head and a recording apparatus of an ink jet recording system in which flying droplets are formed by utilizing thermal energy and recording is performed, among the ink jet recording systems.

The typical structure and principle are disclosed in, for example, US Pat. Nos. 4,723,129 and 4,740,796, and the present invention is not limited to those performed using these basic principles. preferable. This recording method can be applied to both on-demand type and continuous type.

The recording method will be described briefly. An electrothermal transducer disposed in correspondence with a sheet or a liquid path holding a liquid (ink), and a liquid (ink) corresponding to recording information. By applying at least one drive signal for exceeding the nucleate boiling phenomenon and giving a rapid temperature rise that causes the film boiling phenomenon, heat energy is generated, and film boiling occurs on the heat-acting surface of the recording head. . As described above, since bubbles corresponding to the drive signal applied to the electrothermal converter from the liquid (ink) can be formed one-to-one, it is particularly effective for an on-demand type recording method. The liquid (ink) is ejected through the ejection hole by the growth and shrinkage 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 liquid (ink) having particularly excellent responsiveness can be achieved, which is more preferable. Examples of the pulse-shaped drive signal include U.S. Patent Nos. 4,463,359 and 4,345,2.
Those described in the specification of No. 62 are suitable.
Further, when the conditions described in US Pat. No. 4,313,124 relating to the temperature rise rate of the heat acting surface are adopted, more excellent recording can be performed.

The configuration of the recording head is a combination of a discharge hole, a liquid flow path, and an electrothermal converter (a linear liquid flow path or a right-angle liquid flow path) as disclosed in the above-mentioned respective specifications. In addition, as disclosed in U.S. Pat. No. 4,558,333 and U.S. Pat. No. 4,459,600, those having a configuration in which a heat acting portion is arranged in a bent region are 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 hole of an electrothermal converter for a plurality of electrothermal converters, and absorbs pressure waves of thermal energy. The present invention is also effective in a configuration based on JP-A-59-138461, which discloses a configuration in which an opening corresponds to a discharge unit.

Further, as a recording head in which the present invention is effectively used, there is a full line type recording head having a length corresponding to the maximum width of a recording medium on which a recording apparatus can record. The full line head may be a full line configuration by combining a plurality of recording heads as disclosed in the above specification, or may be a single full line recording head formed integrally.

In addition, the print head is replaceable with a print head of a chip type which is electrically connected to the main body of the apparatus and can supply ink from the main body of the apparatus, or is integrated with the print head itself. The present invention is also effective when a cartridge-type recording head provided in a fixed manner is used.

It is preferable to add recovery means for the printhead, preliminary auxiliary means, and the like to the recording apparatus of the present invention because the recording apparatus of the present invention can be further stabilized. If these are specifically mentioned, a capping unit, a cleaning unit, a pressurizing or suction unit, a preheating unit using an electrothermal converter or another heating element or a combination thereof, a recording head, It is also effective to add a means for performing a preliminary ejection mode for performing another ejection for performing stable printing.

Further, the recording mode of the recording apparatus is not limited to a mode for recording only the mainstream color such as black, and may be a mode in which a recording head is integrally formed or a configuration in which a plurality of recording heads are combined. However, the present invention is extremely effective for an apparatus provided with at least one of multiple colors of different colors or full color by mixing colors.

In the embodiments of the present invention described above, liquid ink is used. However, in the present invention, ink which is solid at room temperature or ink which becomes soft at room temperature is used. Can be used. In general, in the above-described ink jet apparatus, the temperature of the ink itself is controlled within a range of 30 ° C. or more and 70 ° C. or less to control the temperature so that the viscosity of the ink is in a stable ejection range. It is sufficient if the ink is in a liquid state.

[0086] In addition, an excessive increase in the temperature of the head or the ink due to thermal energy can be positively prevented by using it as energy for changing the state of the ink from a solid state to a liquid state, or to prevent evaporation of the ink. For example, an ink that solidifies in a standing state may be used. In any case, the ink is liquefied for the first time by the application of heat energy, such as one in which the ink is liquefied and ejected as an ink liquid by application of the heat energy according to the recording signal, or one which already starts to solidify when reaching the recording medium. The use of an ink having the following properties is also applicable to the present invention.

Such an ink is disclosed in JP-A-54-56847 or JP-A-60-71260.
A configuration may be adopted in which the liquid sheet or the solid substance is held as a liquid or solid substance in the recesses or through holes of the porous sheet and faces the electrothermal converter.

In the present invention, the most effective one for each of the above-mentioned inks is to execute the above-mentioned film boiling method.

[0089]

As described above, according to the present invention, the ejection recovery sequence is changed according to the color and composition of the ink ejected by the recording means and the processing history of the ejection recovery processing device, so that the recording between different recording heads can be performed. There is an effect that mixing of ink can be prevented. As a result, it is possible to prevent a decrease in print quality caused by mixing different kinds of inks, and it is possible to always obtain good print quality. Also, by changing the control of the ejection recovery process according to the type of ink ejected by the recording head, the amount of ink ejected by suction and the time required for the process can be minimized, and the size of the waste ink tank can be increased. ,
It is possible to minimize the influence on the throughput and the like.

[Brief description of the drawings]

FIG. 1 is a perspective view illustrating a configuration of an ink jet recording apparatus according to an embodiment of the present invention.

FIG. 2 is a perspective view of the head cartridge as viewed from below.

3 (A) is an exploded perspective view of the head cartridge of FIG. 2, and FIG. 3 (B) is an external perspective view of the head cartridge as viewed from the front side.

FIG. 4 is a perspective view showing a top plate of the head cartridge.

FIG. 5 is a partial perspective view schematically illustrating a structure of an ink ejection unit of the ejection unit.

FIG. 6 is an exploded perspective view showing the configuration of the ejection recovery device.

FIGS. 7A and 7B are views showing details of the cap, wherein FIG. 7A is a front view, FIG. 7B is a plan view, and FIG. 7C is a cross-sectional view taken along line C in FIG.

FIG. 8 is a cam chart of the ejection recovery device.

FIGS. 9A to 9E are diagrams illustrating the movement of the piston of the discharge recovery device.

FIG. 10 is a flowchart illustrating control for selecting an optimal ejection recovery process in the first embodiment.

FIG. 11 is a flowchart showing control contents of an ejection recovery process.

FIG. 12 is a flowchart showing control contents of an idle suction operation.

FIG. 13 is a block diagram illustrating a configuration example of a control system.

FIG. 14 is a flowchart illustrating control in the second embodiment.

FIG. 15 is a flowchart illustrating control according to the fourth embodiment.

[Explanation of symbols]

 9 Head Cartridge 9a Discharge Unit 9b Ink Tank 11 Carriage 12 Restriction Plate 33 Platen 51 Cap 51a Rib 53 Pump 59 Blade 63 Cam Device 113 Heater 121 Cap Cleaner 123 Wiper Cleaner 221 Discharge Port Forming Surface 222 Discharge Port

Continued on front page (72) Inventor Hideaki Kawakami 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (72) Inventor Hitoshi Nakamura 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (72) Inventor Hiroyuki Inoue 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (72) Inventor Soichi Hiramatsu 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (72) Invention Person Akira Miyagawa 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (72) Inventor Hideki Yamaguchi 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (72) Inventor Akira Kida Tokyo 3-30-2 Shimomaruko, Ota-ku, Tokyo Within Canon Inc. (56) References JP-A-6-328727 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B41J 2 / 21 B41J 2/165 B41J 2/18 B41J 2/185

Claims (12)

(57) [Claims] 1. A recording medium for discharging ink onto a recording medium, a cap for covering a discharge port forming surface of the recording means, and a suction force acting on the cap to suction ink from the recording means. An ink jet recording apparatus comprising: a suction unit for performing a suction process for performing ink discharge; and a discharge and discharge unit for performing a discharge and discharge process for discharging ink to a portion other than the recording medium. The recording means for performing the processing is referred to as a first recording means, and the recording means which has performed the suction processing immediately before is referred to as a second recording means.
When the recording means, the first of said suction processing Lima other in accordance with the combination of types of ejection ink recording means and the type of discharging ink of said second recording means to said discharge discharge treatment An ink jet recording apparatus, wherein a control operation is changed. 2. The ink jet recording apparatus according to claim 1, wherein the change in the control operation is a change in the amount of ink suction during the suction process. 3. The ink jet recording apparatus according to claim 1, wherein the change in the control operation is a change in the number of executions of the suction process. 4. The apparatus according to claim 2, further comprising a pump for applying the suction force, wherein the ink suction amount is changed by changing a stroke of a piston slidably disposed in the pump. Inkjet recording device. 5. The ink jet recording apparatus according to claim 1, wherein the change in the control operation is a change in the number of executions of idle suction performed before the suction process. 6. The ink jet recording apparatus according to claim 1, wherein the control operation changes according to the number of times of idle suction performed after a previous discharge / ejection process. 7. When the mounted recording means is replaced with a recording means which ejects a different ink, the suction process is performed from the time of the replacement until immediately before the first printing is performed thereafter. The inkjet recording apparatus according to claim 1, wherein: 8. The ink jet recording apparatus according to claim 1, wherein the change in the control operation according to the combination of the types of ink is a change in the control operation according to the difference in ink density. 9. A recording device for discharging ink onto a recording medium, a cap for covering a discharge port forming surface of the recording device, and a suction force acting on the cap to suction ink from the recording device. In an ink jet recording apparatus having a suction unit for performing a suction process for performing ink discharge and a discharge and discharge unit for performing a discharge and discharge process for discharging ink to a medium other than the recording medium, the type of ink discharged by the recording unit Identifying means for identifying; storing means for storing the type of ink; reading the type of ink of the recording means which performed the suction process immediately before with reference to the storing means; said suction processing Lima <br/> other with respect to the recording means in accordance with a combination of the type of ink identified by means performs control of the discharge the discharge process, the identification hand In ink jet recording apparatus characterized the type of the identified inks to a control means for storing in the memory means. 10. An ink jet recording apparatus according to claim 9, wherein said control means changes control contents in accordance with a difference in density of ink colors. 11. The ink jet recording apparatus according to any one to recording means claims 1 to an ink jet recording means has an electrothermal transducer for generating thermal energy for discharging ink 10. 12. The ink jet recording apparatus according to claim 11 , wherein the ink is ejected from an ejection port using film boiling generated in the ink by thermal energy applied by the electrothermal converter.