JPH0768795A - Ink jet recorder - Google Patents

Abstract

PURPOSE:To lower a cost by reducing an ink consumption amount at the suction recovery of a plurality of recording heads and the size of a waste ink containing part and to easily set an optimum recovery action condition in accordance with a composition of ink in every recording head. CONSTITUTION:One or more suction recovery means 14 each consisting of a suction pump 16 and a suction cap 41 are provided for a plurality of recording heads 1A-1D. Whether or not a suction recovery is required is detected for every recording head at a predetermined timing. Only the selected recording heads are subjected to a suction recovery under suction conditions, such as an initial suction pressure, a suction amount, and a suction interval, specifically set for every recording head.

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 recording by ejecting ink from a recording means onto a recording material.

[0002]

2. Description of the Related Art A recording device having a function such as a printer, a copying machine, a facsimile, or a recording device used as an output device such as a composite electronic device including a computer and a word processor, a workstation, etc. Image (including characters etc.) on the recording material (recording medium) such as paper or plastic thin plate based on
Is configured to record. The recording apparatus can be classified into an ink jet type, a wire dot type, a thermal type, a laser beam type, etc., depending on the recording method.

In a serial type recording apparatus which employs a serial scan system in which main scanning is performed in a direction intersecting a conveyance direction (sub-scanning direction) of a recording material, the recording material is set at a predetermined recording position and then the recording material is recorded. An image is recorded (main scanning) by a recording unit mounted on a carriage that moves along the material, and a predetermined amount of paper is fed (conveyed material to be recorded) after the recording for one line is completed, and then, again. The recording of the entire recording material is performed by repeating the operation of recording (main scanning) the image of the next row on the recording material that has stopped. On the other hand, in a line type recording apparatus that records only by sub-scanning in the conveying direction of the recording material, the recording material is set at a predetermined recording position, and the paper is continuously recorded while recording one line at a time. Feeding (pitch feeding) is performed to record the entire recording material.

Among the above recording apparatuses, an ink jet type recording apparatus (ink jet recording apparatus) performs recording by ejecting ink from a recording means (recording head) onto a recording material, and the recording means can be made compact. Easy, high-definition and high-quality images can be recorded at high speed, and can be recorded on plain paper without requiring special processing,
It has advantages such as low running cost, less noise due to the non-impact method, and easy recording of color images using multicolor inks. Among them, the line type using a full multi type recording means in which a large number of ejection openings are arranged in the paper width direction can further speed up recording.

In particular, an ink jet type recording means (recording head) for ejecting ink by utilizing heat energy,
Through the semiconductor manufacturing process such as etching, vapor deposition, and sputtering, the electrothermal converter formed on the substrate, the electrode,
By forming the liquid passage wall, the top plate, and the like, it is possible to easily manufacture a liquid discharge device having a high-density liquid passage arrangement (ejection port arrangement), and to further reduce the size. On the other hand, there are various requirements for the material of the recording material,
In recent years, ordinary recording materials such as paper and resin thin plates (OHP)
Etc.), thin paper and processed paper (paper with punched holes for filing, perforated paper, paper of arbitrary shape, etc.) have been required to be used.

In an ink jet recording apparatus, the ejection port is covered for use in performing a suction recovery operation for sucking ink from the ejection port to eliminate ejection failure, or for preventing ink from drying at the ejection port. There is a cap for. In addition, when bubbles that have not been defoamed during ink ejection enter the ejection port too much or the volume of the bubble becomes too large, the ejection port may be blocked and the ink flow path cannot be secured. Sometimes. In order to remove the bubbles, the suction recovery operation is often performed.

An ink jet recording apparatus having a plurality of recording heads, for example, B (black), C (cyan), M
A suction recovery system in a color inkjet recording apparatus having four (4) recording heads of (magenta) and Y (yellow) includes a plurality (4) of caps and a plurality of (4) suction pumps respectively connected to the caps. A plurality of (four) caps and one large suction pump connected to all the caps are provided, and all the recording heads are suction-recovered at the same timing.

Further, in the ink jet recording apparatus, when unnecessary ink adheres to the ejection port surface (the surface on which ejection ports are arranged) of the recording head (recording means), the ejection direction of the ink is biased and the image quality deteriorates. There is a case. That is, in the inkjet recording method, since ink droplets are ejected from a recording head onto a recording material such as paper or an OHP film to perform recording, fine floating ink droplets or recording material other than the ejected main ink droplets are generated. When the ink droplets that hit the surface bounce off, the ink adheres to the ejection port surface and becomes wet, and if a large amount of this adhering ink collects around the ejection port, ejection is impeded and ejection occurs in an unexpected direction ( Twisting, and ink droplets may not be ejected (non-ejection).

In an ink jet recording apparatus, a recording head is used as a means for eliminating the above-mentioned inconvenience caused by using a liquid (ink) as a recording material and recovering or maintaining the ejection port surface in a good state. Recovery means (recovery system) is used. As a means for refreshing the ejection opening surface and preventing the deviation of the ejection direction, a wiping member that comes into contact with the ejection opening surface is provided, and the foreign materials such as ink droplets are wiped (wiping) by relatively moving the both. Is used.

Unwanted ink droplets adhering to the ejection port surface are also generated due to ink mist generated at the time of ink ejection during recording or ink rebound from paper. Also,
Foreign substances such as paper dust may adhere to the ejection port surface because the recording head and the sheet move close to each other during recording. Therefore, in general, the wiping means removes ink droplets and foreign matter on the ejection port surface during and after recording.

As the wiping means, a structure in which unnecessary ink droplets are wiped off is widely adopted by wiping the ejection opening surface with a blade formed of an elastic member such as rubber. However, such wiping means deteriorates in function due to long-term use or temporary increase in ink to be wiped, making it difficult to recover and maintain the ejection performance, and further, the wiping means accumulates on a blade as a wiping means. In some cases, the thickened ink, foreign matter, and the like are transferred to the ejection port surface in the opposite direction, causing irregularity in the ejection direction and non-ejection due to embedding of foreign matter.

Further, when the ejection port surface of the recording head is wiped, a part of the wiped ink may be scattered into the recording apparatus by the elastic force of the plate and may contaminate the inside of the apparatus. Furthermore, most of the ink remaining on the blade without being scattered and foreign matters such as paper dust remain attached to the blade. By evaporating the water content of the ink as it is attached to the blade, the ink itself thickens,
In some cases, foreign matter such as paper dust is strongly adhered and accumulated, and this is transferred back to the ejection port surface to cause ejection failure such as non-ejection or twisting.

Two or more recording heads (recording means)
When recording a color image using multiple different color inks, the ink transferred to the blade by the first wiping mixes with the ink of the next recording head when wiping the recording head of the different color. However, the image quality may be degraded. Further, in the case of a color inkjet recording apparatus, wiping a plurality of recording heads with one blade increases the amount of ink adhering to the blade, and the adverse effect of blade contamination increases. Therefore, a configuration in which a dedicated blade is provided for each recording head is conceivable, but this has the drawbacks that the cost is very high and that a considerable installation space is required.

In order to prevent the above-mentioned deterioration of the wiping function, it has been proposed to provide a cleaning means for cleaning the wiping means. As an optimum and general form of this cleaning means, a porous ink absorber having excellent ink absorbing performance is used. By contacting the blade or the like as the wiping means and moving relatively, the ink absorber can remove the foreign matter adhering to the blade by rubbing and remove the ink and clean the blade.
However, even if the ink absorber has excellent cleaning performance, the ink absorption performance may decrease as the ink is absorbed, and it is difficult to maintain reliability for a long period of time.

When ink adheres to the ejection port surface,
When the ink is discharged from the liquid path by a pump or the like, the discharged ink may adhere. In an ink jet recording apparatus, the ink in the liquid passage may thicken due to evaporation of water or the like, and may not be ejected even if ejection energy is applied.Therefore, ink that is not suitable for ejection is forcibly ejected. A suction pump or the like is generally used as a means for refreshing the ink in the liquid path. At that time, the ink adhesion amount after suction may be larger than the ink adhesion amount during recording, and in such a case, the load applied to the wiping unit also becomes large.

FIG. 19 is a schematic sectional view for explaining the operation of the cap at the time of suction recovery. FIG. 19A shows
After the cap 103 is brought into close contact with the ejection port surface 102 of the recording head 101 and a negative pressure is generated by a suction pump (not shown) connected to the cap 103 to suck ink from the ejection port, the negative pressure is almost eliminated. 6 shows a capping state when the discharge is performed (a capping state when the negative pressure is reduced to such an extent that the meniscus of the discharge port is not destroyed). The shaded portion 104 in FIG. 19 indicates the ink that has been sucked out. In the state of FIG. 19A, the cap 103
It is considered that the inside of the is almost filled with ink.

When attempting to separate the cap 103 from the capped state of FIG. 19A, as shown in FIG. 19B, at the interface between the ejection port surface 102 and the ink 104, the adhesive force of the ink and the inside of the ejection port The negative pressure of the ink acts on the ink to suck up the ink, and the cap 103
The surface tension that the ink itself tends to aggregate acts on the ink inside. Therefore, as shown in (c) of FIG.
Constrictions 105 occur between the inks 104. Cap 1
As 03 is separated, the cross-sectional area of each constricted portion 105 of the ink 104 becomes smaller and becomes weakest.

Finally, as shown in FIG. 19D, the connection between the inks is broken at each constriction 105, and a part of the ink remains on the ejection port surface 102. At this time, the amount of ink remaining on the ejection port surface 102 is larger than the amount of ink adhered by the mist during recording, the lower the surface tension of the ink, and the ejection port surface 102.
The lower the water repellency of, the higher the tendency is to increase. The larger the amount of ink adhering to the ejection port surface 102, the greater the load on the wiping blade and the wiper cleaner.
Their life is shortened. Further, in the example shown in FIG.
Since ink remains in the cap 103 when the cap 103 is separated, ink dripping and scattering also pose a problem.

Further, immediately after the ink is sucked, the cap 10
When 3 is separated, a negative pressure remains and atmospheric pressure is instantaneously applied to the cap, and the meniscus in the discharge port is destroyed by the sudden pressure fluctuation at this time and the mechanical shock at the time of separation, and the air is deep inside the discharge port. May enter and cause defective ejection of ink.

[0020]

The suction recovery operation of the conventional ink jet recording apparatus does not depend on the gravity of the ink,
It is performed by using a cylinder pump that can reliably collect ink even when horizontally arranged by using the movement of a piston. This cylinder pump opens and closes an opening for collecting waste ink from an ink receiving member such as a cap by the surface of the piston, and through the waste ink moving path provided on the shaft side of the piston, the ink receiving port is opened. It is configured to move the waste ink to a waste ink storage unit having a higher ink storage capacity than the member.

However, in the suction recovery means of the conventional ink jet recording apparatus using a plurality of recording heads for color recording or the like, a structure having a cap corresponding to each recording head and a suction pump corresponding to each cap, Alternatively, since a structure having a cap corresponding to each recording head and a large suction pump connected to all caps is adopted and the suction recovery operation is performed for all of the plurality of recording heads at the same timing, The amount of ink increases in proportion to the number of recording heads, and the waste ink storage section must also increase in proportion to this, which is a disadvantage in that the recording apparatus becomes large.

Performing the suction recovery operation of all the print heads at the same timing also sucks the ink from the print heads that do not need to be sucked due to the frequency of use of each print head or the ink characteristics. Ink will be wasted. This wasteful ink consumption is "reduced to the ink of the unused print heads" for users who mainly use a particular print head (for example, monochrome users).
Will give you an unpleasant feeling.

Furthermore, in order to solve the above-mentioned inconveniences related to defective ink ejection, for example, JP-A-60-151.
No. 059, the cap and the air intake valve are connected by a tube, and the air intake valve is opened to allow the inside of the cap to communicate with the atmosphere so that the ink remaining in the cap is sucked. The method of separating the cap is adopted. However, recent inkjet recording apparatuses tend to be miniaturized, and accompanying this, it is necessary to reduce the size of the cap and its peripheral mechanism, so it is difficult to provide the air intake valve as described above in a small cap. is there. In addition, the tube used for the connection with the air intake valve may be clogged with dust and may not function.

Further, a certain amount of negative pressure is required to discharge dust adhering to the ejection port surface, bubbles in the ejection port and thickened ink. Therefore, the cap is provided with the air intake valve as described above. In the configuration, there is also a disadvantage that the cap itself becomes large and the suction amount accordingly increases. Furthermore, when the suction amount is increased, the amount of waste ink and the running cost are increased.

The present invention has been made in view of the above technical problems, and an object of the inventions of claims 1 to 6 is to reduce the amount of waste ink and miniaturize the waste ink storage portion. At the same time, the recording apparatus itself is downsized, wasteful ink consumption is reduced, cost is reduced, and discomfort for a user who uses only a specific recording unit is eliminated. It is an object of the present invention to provide an inkjet recording apparatus capable of setting a suction amount, a suction interval, an initial suction pressure, etc. corresponding to a difference in composition.

It is an object of the inventions of claims 7 to 11 to remove the ink adhering to the ejection port surface of the recording means (recording head) as much as possible to prevent the performance of the wiping means from being deteriorated and to eject the ink of the recording means. It is an object of the present invention to provide an ink jet recording apparatus which can stabilize the recording medium, can perform good recording for a long period of time, and can prevent color mixture of ink when using a plurality of recording means.

The objects of the inventions of claims 12 to 18 are:
By removing the ink adhering to the ejection port surface of the recording unit (recording head) as much as possible, it is possible to prevent performance deterioration of the wiping unit, stabilize the ink ejection of the recording unit, and perform good recording for a long time. Another object of the present invention is to provide an inkjet recording device capable of preventing color mixing of ink when using a plurality of recording means.

[0028]

According to a first aspect of the invention, in an ink jet recording apparatus for recording by ejecting ink from a recording means to a recording material, a plurality of recording means and suction recovery means are provided, and selectively. By adopting a configuration having an operation sequence for performing suction recovery of only a certain recording unit, the amount of waste ink is reduced, the waste ink storage unit is downsized, and the recording apparatus itself is also downsized, thereby reducing wasteful ink consumption. The cost is reduced, the discomfort for the user who uses only a specific recording means is eliminated, and the suction amount, suction interval, and initial suction pressure corresponding to the difference in the composition of the ink used in each recording means. The present invention provides an inkjet recording apparatus capable of setting the above.

In addition to the above configuration, the inventions of claims 2 to 4 detect the necessity of suction recovery at a predetermined timing,
According to the result, only specific recording means is sucked and recovered,
More efficient by setting the suction conditions such as initial suction pressure, suction amount, suction interval, etc. individually for each recording means, or not performing the suction for the recording means not used. The above object is achieved.

According to a seventh aspect of the invention, in an ink jet recording apparatus for recording by ejecting ink from a recording means to a recording material, the ejection port of the recording means is covered with a cap and the ink is forcibly ejected from the ejection port. By including a recovery means and the capacity of the ink absorber provided in the cap being larger than the discharge amount of one operation of the recovery means, the ink adhering to the ejection port surface of the recording means is removed as much as possible. The inkjet recording can prevent deterioration of the performance of the wiping device, stabilize the ink ejection of the recording device, perform good recording for a long time, and prevent color mixture of ink when using a plurality of recording devices. A device is provided.

In addition to the above-mentioned structure, the invention of claims 8 and 9 has a structure in which the recovery means forcibly discharges the ink by a suction operation, or the suction operation is completed by opening the cap at a predetermined timing. By adopting such a constitution, the above object can be achieved more efficiently.

According to a twelfth aspect of the invention, in an ink jet recording apparatus for recording by ejecting ink from a recording means to a recording material, the ejection port of the recording means is covered with a cap and the ink is forcibly ejected from the ejection port. By including a recovery means and the capacity of the ink absorber provided in the cap being larger than the inner volume of the ink flow path of the recording means, the ink adhering to the ejection port surface of the recording means is removed as much as possible. The inkjet recording can prevent deterioration of the performance of the wiping device, stabilize the ink ejection of the recording device, perform good recording for a long time, and prevent color mixture of ink when using a plurality of recording devices. A device is provided.

In addition to the above construction, the invention of claims 13 to 16 is such that the recovery means forcibly discharges the ink by the suction operation, and the suction operation is ended by opening the cap at a predetermined timing. More efficient by the configuration, the amount of ink discharged by the recovery unit is larger than the inner volume of the ink flow path of the recording unit, or the amount of ink discharged by the recovery unit is smaller than the capacity of the ink absorber in the cap. It often achieves the above object.

[0034]

Embodiments of the present invention will be described below with reference to the drawings. In addition, in each drawing, the portions denoted by the same reference numerals indicate the same or corresponding portions.
FIG. 1 is a schematic perspective view showing a main part configuration of an inkjet recording apparatus suitable for applying the present invention. In FIG. 1, a plurality (4) of head cartridges (recording means) 1
A, 1B, 1C, and 1D are exchangeably mounted on the carriage 2. In the following description, the recording means 1A
When referring to 1D to whole or any one of them, it is simply indicated by the recording means (recording head or head cartridge) 1. FIG. 2 is a perspective view showing any one head cartridge 1.

As shown in FIG. 2, each head cartridge 1 has an ink tank portion 21 in the upper portion and a recording head portion (ink ejection portion) 22 in the lower portion, and the recording head and the ink tank are integrated. It has a simplified structure. An ink ejection unit 13 is provided near the front surface (the surface facing the recording material) of the recording head unit 21. The plurality of head cartridges 1 respectively record with different inks, and in the case of color recording, different inks such as black, cyan, magenta, and yellow are stored in the ink tank portions 21.

Each recording means 1 is mounted on the carriage 2 so as to be positioned and replaceable. Each recording means 1 has a connector (not shown) for receiving a signal for driving the recording head portion 22. ) Is provided. On the other hand, the carriage 2 is provided with a connector holder (electrical connection portion) for transmitting a drive signal or the like to each recording means 1 through the connector. Then, each recording means 1 on the carriage 2 and the control circuit on the apparatus main body side are connected by a flexible cable for flowing a signal pulse current or a temperature control current.

The carriage 2 is guided and supported so as to be able to reciprocate along a guide shaft 3 installed in the main body of the apparatus so as to extend in the main scanning direction. And the carriage 2
Is driven by a main scanning motor 4 via a motor pulley 5, a driven pulley 6 and a timing belt 7, and its position and movement are controlled. A recording material 8 such as a sheet of paper or a thin plastic plate is sandwiched between two sets of conveying roller pairs 9, 10 and 11, 12 and a position facing the ejection port surface of the recording head 1 by the rotation of these conveying rollers ( It is conveyed (paper feed) through the recording unit. The recording material 8
Has a back surface supported by a platen (not shown) so as to form a flat recording surface in the recording portion. In this case, the head cartridges 1 mounted on the carriage 2 are held so that their ejection port surfaces project downward from the carriage 2 and are parallel to the recording material 8 between the two pairs of the transport rollers. ing.

The recording head (recording means) 1 is an ink jet recording means for ejecting ink by utilizing heat energy, and is provided with an electrothermal converter for generating heat energy. In addition, the recording head 1 performs recording by ejecting ink from an ejection port by utilizing a pressure change caused by growth and contraction of bubbles due to film boiling generated by thermal energy applied by the electrothermal converter. is there.

FIG. 3 is a partial perspective view schematically showing the structure of the ink ejecting section 13 of the recording head section 22. Figure 3
At a predetermined gap (for example, about 0.5
A plurality of ejection openings 82 are formed at a predetermined pitch on the ejection opening surface 81 facing each other with a distance of about 2.0 mm), and each of the liquid passages 84 that communicates the common liquid chamber 83 with each ejection opening 82. An electrothermal converter (heat generating resistor, etc.) 85 for generating energy for ejecting ink is arranged along the wall surface.
In this example, the recording head 1 is mounted on the carriage 2 in such a positional relationship that the ejection ports 82 are arranged in a direction intersecting the scanning direction of the carriage 2. Thus
A recording head that drives (energizes) the corresponding electrothermal converter 85 based on an image signal or an ejection signal to cause the ink in the liquid path 84 to film-boiling and eject the ink from the ejection port 82 by the pressure generated at that time. The part 22 is configured.

In FIG. 1, a recovery system unit 14 is arranged at the home position of the recording head 1 (carriage 2) installed on the left side of the recording apparatus. The recovery system unit 14 includes the ink ejection unit 1 of each head cartridge 1.
3 and a cap unit including a plurality of (four) caps 15 arranged corresponding to each
And a pump unit (suction pump) 16 connected by a tube 19 or the like. The cap unit (each cap 15) can move up and down in accordance with the movement of the carriage 2 when the carriage 2 is approaching, and when the carriage 2 is at the home position, the cap unit (each cap 15) comes into close contact with the ejection port surface 81 of each recording head 1. To seal the discharge port 82 (capping)
Is configured to. With this capping,
The thickening or sticking of the ink in the ejection port 82 due to the evaporation of the ink is prevented, and the ejection failure is prevented.

In the unlikely event that the recording head 1 has a defective ejection, the pump unit 16 is operated under the capping state to generate a negative pressure, and the negative pressure suction force sucks out the ink from the ejection port 82. Thus, the operation for recovering the ejection performance, that is, the suction recovery operation is performed. Further, the recovery system unit 14 is provided with a blade 18 held by a blade holder 17 located between the cap 15 and the recording material conveying section. The blade 18 is a wiping member formed of a rubber-like elastic material, and is used for wiping and cleaning the ejection port surface 81 by using the movement of the carriage 2. In this embodiment, the blade holder 17 is moved up and down by a blade elevating mechanism (not shown) that is driven by the movement of the carriage 2, so that the blade 18 is projected (wiping position) and retracted (standby position). ) Can be set to. When the blade 18 is at the protruding position (raised position), foreign matter such as ink attached to the ejection port surface 81 can be wiped off at the tip of the blade. Further, when the blade 18 is in the retracted position (lowered position), it does not contact (interfere) with the ejection port surface 81.

FIG. 4 is a vertical sectional view showing the structure of the recording head portion 22 of the head cartridge 1. In FIG. 4, a heater board 24 formed by a semiconductor manufacturing process is provided on the upper surface of the support body 23. On the heater board 24, a temperature adjusting heater 25 for keeping the temperature of the recording head 22 and adjusting the temperature is formed by the same semiconductor manufacturing process. A wiring board 26 is disposed on the support 23, and the wiring board 26 is a heater 25 for temperature control.
Also, it is connected to the discharge heater (electrothermal converter) 85 by wire bonding or the like. Further, the temperature adjusting heater 25 may be a heater member formed by a process different from that of the heater board 24 and attached to the support body 23 or the like.

In FIG. 4, 27 is a discharge heater 85.
Indicates a bubble generated by heating the ink in the liquid path 84. Reference numeral 28 denotes an ink droplet ejected from the ejection port 82 due to a pressure change caused by the generation of the bubble 27. A common liquid chamber 83 communicates with each discharge port 82.

FIG. 5 is a vertical sectional view showing the construction and operation of the pump unit (suction pump) 16 in FIG. Figure 5
At the front end of the piston shaft 31, a piston pressing roller 32 is rotatably supported, and when a piston set cam (not shown) presses the piston pressing roller 32 by the rotation of a timing gear (not shown), the piston shaft 31 moves. (A)
Move in the direction of arrow H as shown in. The piston 33, which is slidably fitted into the inner diameter of the cylinder 35, is pushed by the piston retainer 31b of the piston shaft 31 and is indicated by the arrow H.
Direction, the pump chamber 34 is in a negative pressure state. Since the skin layer is formed on the outer circumference of the piston 33 and the contact surface with the piston retainer 31b, ink does not leak.

Since the ink passage 35e of the cylinder 35 is blocked by the piston 33 for a certain period after the piston shaft 31 starts moving in the direction of the arrow H, the piston shaft 31 is closed.
The negative pressure in the pump chamber 34 increases in accordance with the movement in the direction of arrow H. The ink flow path 35e is provided with a cap lever 36.
The ink passage 36f communicates with the suction port of the cap 15 (FIG. 1). Therefore, after the ejection port surface 81 of the recording head 22 is capped by the cap 15, the piston shaft 31 is moved in the direction of arrow H to move the pump chamber 3
When the negative pressure of 4 is increased and the piston shaft 31 further moves in the direction of arrow H, the ink flow path 36f opens as shown in (B), and this state is maintained for several seconds.

In this state (B), the cap 15
Ink is sucked from the ejection port 82 of the recording head 22 due to the negative pressure generated inside, and the sucked ink is absorbed by the cap 15
From the suction port of the ink passage 3 inside the cap lever 36.
6f and the ink flow path 35e of the cylinder 35,
It is introduced into the pump chamber 34. With the introduction of this ink, the negative pressure in the pump chamber 34 is alleviated.

At this time, the timing gear (not shown) further rotates and the cap cam (not shown) causes the cap 15 to move.
Are slightly separated from the discharge port surface 81. Here, as the piston shaft 31 further moves in the direction of the arrow H as shown in (B), the discharge port surface 81 and the inside of the cap 15, and the suction port of the cap to the tube 19 (may not exist) and The residual ink up to the respective ink flow paths 36f and 35e is sucked, and the ink remains in these portions is eliminated. At this time, in order to remove the residual ink from the cap 15 to the ink flow path 35e, it is necessary to increase the negative pressure in the pump chamber 34, and for that purpose, the moving speed of the piston shaft 31 in the arrow H direction. It is better to increase the efficiency.

Next, when the timing gear (not shown) is rotated in the opposite direction, the piston reset cam (not shown) pulls the piston return roller (not shown), as shown in FIGS. 5C and 5D. Thus, the piston shaft 31 moves in the arrow J direction. However, since the piston 33 moves in the direction of arrow J after the piston receiver 37 on the piston shaft 31 contacts the piston 33, there is a gap between the end surface 33b of the piston 33 and the piston retainer 31b.
A gap Δl as shown in (C) and (D) is generated. Therefore, as the piston 33 and the piston shaft 31 move in the direction of arrow J, the waste ink sucked into the pump chamber 34 flows from the gap Δl into the groove 31f of the piston shaft 31.
And 31 g, and the ink flow path 3 of the cylinder 35.
5c and the waste ink pipe 35h, and the waste ink absorber 3
8 is discharged near the hollow.

6 to 9 are schematic diagrams showing the construction and operation of the first embodiment of the suction recovery means of the ink jet recording apparatus to which the present invention is applied. 6 to 9, in this embodiment, four recording heads (head cartridges) 1A to 1D of black (B), cyan (C), magenta (M), and yellow (Y) are mounted on the carriage 2. The case of the color ink jet recording apparatus that has been prepared is shown. Further, in this embodiment, the suction recovery means including one suction cap 41 and one suction pump 16 is configured to selectively suction the plurality of recording heads 1. Therefore, in addition to the suction cap 41, the same number of protective (storage for leaving) caps 42 as the recording head 1 are provided. It should be noted that the number of the protective caps 42 is the same as the number when the suction caps 41 are used as protective caps
The number may be one less than that of the recording head 1. The control panel 43 of the recording apparatus is provided with a suction switch 44 for performing a suction operation and a color designating switch 45 for designating a color (recording head) for performing a suction operation.

The recovery operation of the suction recovery means shown in FIGS. 6 to 9 is as follows. When performing suction recovery manually,
When the user finds the print head 1 with ejection failure, the corresponding color designation (print head designation) switch 45 and suction switch 44 on the control panel 43 are turned on, as shown in FIGS. 7 and 8. 7 and 8 show a case where an ejection failure of the cyan recording head 1B is found. The carriage 2 is moved by the instruction, and as shown in FIG. 7, the recording head 1B instructed to suction is brought into a state of facing the suction cap 41 in the fixed position. As a modified example, the suction cap may be moved while the carriage 2 is fixed at the home position so that the recording head instructed to suction and the suction cap face each other.

Next, as shown in FIG. 8, the suction cap 41 is brought into close contact with the designated recording head 1B, and the suction pump 16 (FIG. 5) is operated to generate a negative pressure in the cap 41. Thus, the ink is sucked from the recording head 1 (ejection port 82), and foreign matters such as dust and thickened ink in the ejection port 82 are removed. Although the above-described suction recovery operation is performed manually, an ejection failure detection unit that detects which recording head 1 has an ejection failure may be provided to automatically perform the suction recovery operation. . Even when it is automatically performed, the suction recovery operation is performed only for the recording head 1 having the ejection failure by the movement of the carriage 2 or the movement of the suction cap, similarly to the above.

When the recording heads 1 are left unused without being used, such as when the recording apparatus is stored, as shown in FIG. 9, the carriages 2 are moved so that the recording heads 1 face the corresponding protective caps 42. Further, the respective recording heads 1 and the respective protection caps 42 (including the combined use of the suction caps 41) are brought into close contact with each other, so that the respective recording heads 1 are capped (the ejection port 82 is sealed), and the inside of the ejection port 82 is closed. The thickening and sticking of ink and the intrusion of dust into the ejection port 82 are prevented.

According to the suction recovery means described above with reference to FIGS. 6 to 9, the following effects are obtained. First, since only the necessary recording heads can be recovered to the desired extent, the amount of waste ink can be reduced to miniaturize the waste ink storage portion, and wasteful ink consumption can be reduced to reduce costs. I was able to plan. Secondly, when only a specific recording unit is used, it is possible to eliminate the user's discomfort due to the absurdity of sucking up the recording head in which ejection failure has not occurred and discharging the ink unnecessarily. Third, it is possible to set the suction amount, suction interval, initial suction pressure, etc. corresponding to the difference in the composition of the ink used in each of the recording heads 1A to 1D, and it is extremely rational suction recovery in terms of ink consumption. I got the means.

Fourthly, due to the drastic reduction and miniaturization of the suction pump 16, the cost can be drastically reduced. Fifthly, since a single suction pump 16 is used and only the recording heads 1 required during the suction are sequentially positioned to perform the recovery operation, a plurality of recording heads 1 can be simultaneously operated.
It was possible to improve the reliability of the suction operation as compared with the case of positioning and suctioning. Sixth, even if a plurality of recording heads 1 are used, the number of suction pumps 16 can be one, and the capacity of the suction pumps 16 is sufficient for one recording head. , It is no longer necessary to install suction pumps for several recording heads or large-capacity suction pumps corresponding to multiple recording heads as in the past, and the space for the suction pump, which occupies a large space in the recovery system, is greatly increased. Could be reduced to Therefore, the space of the recovery system can be reduced, and the ink jet recording apparatus can be reduced in size and weight.

FIG. 10 is a schematic diagram showing the construction and operation of the second embodiment of the suction recovery means of the ink jet recording apparatus to which the present invention is applied, and FIG. 11 is an example of the suction check sequence of the suction recovery means of FIG. It is a flowchart showing. 10, in the present embodiment, a plurality of sets of suction recovery mechanisms including a suction pump 16 and a suction cap 41 that operate independently are provided for each of the plurality of recording heads 1A to 1D, and a plurality of recording heads are provided. 1A-1D
The recovery operation is selectively performed. Note that all the suction caps 41 in this embodiment also have the function of the above-mentioned protection cap 42, and therefore the protection cap is omitted. Then, the suction recovery operation for each recording head 1 will be described with reference to FIG.
According to the above sequence, it is determined whether or not the recovery operation is performed, and only the suction pump 16 for the recording head 1 that is determined to be suctioned is operated to perform the selective recovery operation.

The recovery operation of the second embodiment shown in FIG. 10 is performed as follows. First, the carriage 2 returns to the home position, and the corresponding suction caps 41 are brought into close contact with the respective recording heads 1 to cap the ejection ports 82. Next, for each recording head 1, it is determined whether a recovery operation is necessary by detecting the presence or absence of certain conditions. For example, in the suction check sequence as shown in FIG. 11, the suction check is started, and step S1 is performed for each recording head 1.
After the elapse of the 3-day timer and the ink drop in step S2, only the recording heads 1 having these recovery conditions are selected, only the suction pump 16 of the selected recording head 1 is operated, and the selective suction operation in step S3. Do.

Note that the flowchart of FIG. 11 also shows a sequence of the cleaning operation that is normally performed after the selective suction is finished and before the recording is started. That is, in FIG. 11, after the selective suction of each recording head 1 is performed, the suction timer is reset to perform the next suction operation in step S4, and the ejection port surface 81 is wiped and cleaned by the wiping blade 18 in step S5. Then, the preliminary ejection from the 500 ejection ports × 64 ejection ports in step S6 and the preliminary ejection from the 50 ejection ports × 64 ejection ports in step S7 are performed.
After carrying out the cleaning operation of, the carriage 2 is returned to the recording area and recording is started.

According to the second embodiment described with reference to FIGS. 10 and 11, the following effects are obtained. First, since only the necessary recording heads can be recovered to the desired extent, the amount of waste ink can be reduced to miniaturize the waste ink storage portion, and wasteful ink consumption can be reduced to reduce costs. I was able to plan. Secondly, when only a specific recording unit is used, it is possible to eliminate the user's discomfort due to the absurdity of sucking up the recording head in which ejection failure has not occurred and discharging the ink unnecessarily.
Third, it is possible to set the suction amount, suction interval, initial suction pressure, etc. corresponding to the difference in the composition of the ink used in each of the recording heads 1A to 1D, and it is extremely rational suction recovery in terms of ink consumption. I got the means.

Fourthly, since the independent suction pump 16 corresponding to each recording head 1 is provided, several recording heads 1 can be suctioned at the same time, and the recovery operation time can be shortened. . Fifth, since the suction pumps 16 are independent of each other, it is possible to easily perform automatic selective suction based on ink drop detection or the like.
Sixth, even for recording heads that do not perform suction operation,
Preliminary ejection and the like can be performed freely, and it becomes possible to set the strength of recovery for each recording head 1. 7th
In addition, by adopting the suction check sequence as shown in FIG. 11, it is possible to automatically perform the suction recovery operation, without excessive ink consumption, and without any troublesome operation for the user. It has become possible to maintain ink ejection performance.

By the way, for example, yellow, magenta,
In a color ink jet recording apparatus having four color recording heads of cyan and black, a black-and-white user who mainly uses black rarely uses colors other than black, but inks that are not used are also lost by suction of all colors. Is expected. However, according to each embodiment of the suction recovery means described above, it is possible to easily prevent excessive suction in such a recording head that is infrequently used. That is, according to the selective suction as in each of the above embodiments, a switch for switching between the monochrome mode and the color mode is provided on the control panel or the like, and only the black recording head is sucked at a constant timing in the monochrome mode, or By using a method of storing the usage frequency of each of the recording heads 1A to 1D in the apparatus main body and sucking only the recording heads that are frequently used, it is possible to determine the frequency of usage for a monochrome user. It is possible to easily reduce the number of times the low-yellow, magenta, and cyan print heads are sucked, so that it is possible to easily realize a suction recovery operation that does not care how the inks other than black are reduced. .

Further, according to the above-mentioned embodiment, the initial suction pressure for each recording head 1 is changed according to the characteristics of the ink.
You can easily change the suction amount and suction interval,
Therefore, the suction operation condition can be freely and optimally adjusted according to the difference in the dye of the ink used in each recording head 1. Further, in order to obtain an image of higher image quality, inks having totally different compositions may be used for each recording head 1. Even in such a case, the initial suction pressure and the suction amount may be changed depending on the ink composition. Further, the suction condition such as the suction interval can be easily changed, and an effective and rational suction operation can be easily performed.

Further, in the ink jet recording apparatus shown in FIG. 1, the wiping of the ejection port surface 81 by the blade 18 is performed only when the carriage 2 moves from the left side (home position side where the recovery unit 14 is located) in FIG. 1 to the right side. Is being carried out. This is because the blade 18 is located between the cap unit 15 and the recording material conveying system, and conversely, when wiping is performed when moving from the right side to the left side in FIG. This is because there is a possibility that the recording material 8 may be scattered by the elastic force and scattered by the recording material transporting portion to stain the recording material 8. If there is no such adverse effect, wiping may be performed in both directions.

FIG. 12 is a bottom view of the carriage 2 seen from the bottom, and FIG. 13 is a front view of the carriage 2 seen from the front. In FIGS. 12 and 13, an ink absorber 51 as a cleaning unit for cleaning the blade 18 is attached to the bottom of the carriage 2 so as to sandwich the ejection port surface 81 of each recording head 1. The ink absorber 51 is composed of a porous absorbing member that has corrosion resistance to ink and has high ink absorbency. The blade cleaning ink absorbers 51 (five in total) are attached so as to be arranged on both sides of the ejection port surface 81 of each recording head 1 as illustrated. In addition, as shown in FIG. 13, each ink absorber 51 is disposed so as to be slightly retracted from the ejection opening surface 81 of each recording head 1 so as not to rub against the recording material 8 during recording. ing.

In the ink jet recording apparatus, if the accuracy of the landing position of the ejected ink droplets on the recording material 8 is poor, white streaks may occur in the image, or conversely black streaks may occur. As one of the measures for preventing such image deterioration, the distance between the ejection port surface 81 of the recording head 1 and the recording surface of the recording material 8 is made as small as possible, and the landing error of the ink droplets is made small. Quality is being improved. However, when the recording material 8 absorbs the ink, there is a large difference in water content between the surface that has absorbed the ink and the back surface thereof, or the portion that has received the ink and the portion that has not received the ink. Recording material 8
There is a case where uneven expansion and contraction occurs, which causes bubbling called cockling. When cockling occurs or the recording material 8 is curled, if the gap between the recording head 1 and the recording material 8 is too small, the recording head 1 and the recording material 8 come into contact with each other and the recording surface. The inconvenience of soiling occurs. Therefore, the recording head 1 and the recording material 8
The distance between and is set so as to be the minimum within a range in which it does not rub even if the cockling or the like is deformed.

In the present embodiment, from the viewpoint of emphasizing the accuracy of the ink landing position, the blade cleaning ink absorber 51 disposed at the bottom of the carriage 2 is projected below the carriage 2. It is attached to a slightly retracted position. In addition, since the ink absorber 51 may absorb ink and swell, the position of the ink absorber 51 is set so as to be retracted from the recording head 1 by about 0.5 mm in consideration of the amount. There is.

FIG. 14 is a schematic front view illustrating the wetting state of the discharge port surface 81 after image recording, and FIG.
FIG. 9 is a schematic front view illustrating a state in which ink is attached to the ejection port surface 81 after performing suction recovery. In general, as described above, the ejection port surface 81 of the recording head 1 after the ink is ejected for recording is in a wetting state as shown in FIG. As shown in FIG. 14, when a considerable amount of ink droplets adhere to the periphery of the ejection port 82, the ejection of the ink is obstructed, and a phenomenon (distortion) of ejecting in an unexpected direction occurs,
There is an adverse effect such as a phenomenon that ink droplets are not ejected (non-ejection). Further, as described above, the ink adheres to the ejection port surface 81 even after the suction recovery, and the ink adhesion amount in that case is larger than that in the case of the wetting due to the ejection as shown in FIG. Therefore, it is necessary to wipe the ejection port surface 81 with the blade 18 after the suction recovery process or after a certain period of time elapses (before causing ejection failure).

FIG. 16 is a schematic diagram showing the wiping operation in this embodiment. As described above, the wiping operation in this embodiment is a direction in which the carriage 2 is moved from the home position side (left side in FIG. 16) to the recording material conveying system side (right side in FIG. 16) only when necessary. Done in.
FIG. 16A shows the state immediately before the wiping operation. At this time, the blade 18 held by the blade holder 17 rises in the arrow Y direction from the standby position to wipe the recording head 1. It is fixed at the position (wiping position) that gives the optimum approach amount. Next, as shown in FIGS. 16B and 16C, the recording head 1
The carriage 2 carrying the carriage horizontally moves from left to right, during which the blade 18 is provided with the ink absorbers 51 arranged at the bottom of the carriage 2 and the ejection port surfaces 81 of the recording heads 1 protruding from the carriage 2. Then, foreign matter such as ink attached to each ejection port surface 81 is wiped and removed while alternately contacting each other. After sequentially contacting all the ink absorbers 51 and the ejection port surface 81, the blade 18 moves (lowers) in the direction opposite to the arrow Y and stands by at the retracted position.

As shown in FIG. 16, since the blade cleaning ink absorbers 51 are disposed at the positions contacting both sides of each recording head 1, the ink wiped from the ejection port surface 81 by the blade 18 is sequentially wiped. Ink absorber 5
As a result, the amount of ink remaining on the blade 18 is always small, and it is possible to prevent color mixing when wiping the ejection port surface 81 of the next recording head 1. However, since the ink absorption capacity of each ink absorber 51 is limited, when the amount of ink adhering to each ejection port surface 81 is large, each ink absorber 5 is not.
Depending on 1, it may not be able to be absorbed sufficiently. However, according to the embodiment described below, the residual ink on the ejection port surface 81 of each recording head 1 can be almost eliminated, and thus the burden of the wiping blade 18 and the blade cleaner (ink absorber) 51 can be eliminated. The burden can be significantly reduced, and the above inconvenience can be eliminated.

FIG. 17 is a schematic sectional view of the cap portion for showing the suction operation of the third embodiment of the suction recovery means of the ink jet recording apparatus to which the present invention is applied. In FIG. 17, a porous ink absorber 52 is provided inside each cap 15 (FIG. 1). This ink absorber 52
Is set to a value larger than the suction amount of the suction pump 16 (FIG. 1) (forced discharge amount of ink in one operation) or a value larger than the internal volume of the ink flow path of the recording head 1. Then, as shown in FIG. 17A, the ink absorber 52 is arranged so as to be located in the vicinity of the ejection port surface 81 during capping. The hatched portion 53 in FIG. 17 indicates the ink sucked (sucked) from the ejection port 82.

In FIG. 17A, the cap 15 is brought into close contact with the discharge port surface 81, the suction pump 16 (FIG. 1) is operated, and a negative pressure is generated in the cap 15 through the tube 19 so that each discharge is performed. The state where the ink 53 is sucked from the outlet 82 is shown. After that, at a predetermined timing, as shown in FIG.
As shown in FIG. 7B, the recording head 1 and the cap 15 are separated and a gap 54 is formed therebetween. This recording head 1
As for the timing of separating the cap 15 from the cap 15, the operation of the suction pump 16 is stopped and a predetermined amount of ink is sucked so that the negative pressure in the suction pump 16 is almost eliminated, or the negative pressure in the cap 15 is reduced. Even when the pressure is applied, the time when a predetermined amount of ink is sucked is selected. The ink sucked from the recording head 1 by the suction pump 16 is sent to a waste ink tank (not shown) and discharged through a tube, an ink flow path, or the like. This waste ink tank is a porous ink absorber that absorbs and holds waste ink (such as the waste ink absorber 38 in FIG. 5).
You may comprise.

In FIG. 17, the porous ink absorber 5 is used.
As described above, the volume of 2 is larger than the suction amount of the suction pump 16 (forced discharge amount of ink in one operation),
Alternatively, it is set to a value larger than the inner volume of the ink flow path of the recording head 1. Therefore, the ink 53 between the ejection port surface 81 and the cap 15 is carried to the ink absorber 52 side by the suction force of the ink absorber 52, as shown in FIG. 17C. Therefore, (d) of FIG.
As shown in, the suction recovery operation can be ended in a state where no ink remains on the ejection port surface 81 of the recording head 1.
In this way, the suction recovery operation is completed in a state where no ink remains on the ejection port surface 81, so that the burden on the wiping blade 18 and the blade cleaner (ink absorber) 51 in FIG. 16 can be greatly reduced. Also, the cap 1
5 is filled with the porous ink absorber 52, the ink flow in the cap 15 at the time of suction can be made directional (direction from the discharge port surface 81 toward the suction pump 16 side), and It is possible to prevent the color mixture in which the different color ink attached to the outlet surface 81 enters the ejection port 82.

It should be noted that in the above-mentioned embodiment, the carriage 2 is set to four.
Although the description has been given by taking as an example the case of a color recording apparatus in which one recording head (head cartridge) 1 is mounted, the number of recording heads 1 is not limited to this, and one recording head or a recording head other than the above may be used. A number of recording heads may be used. In the case of color recording, there is a peculiar problem of color mixing, but the above-described embodiment exerts a great effect in solving the problem of color mixing.

FIG. 18 is a schematic diagram showing the structure and operation of the fourth embodiment of the suction recovery means of the ink jet recording apparatus to which the present invention is applied. 18, in this embodiment, one suction cap 41 and one suction pump 16 are provided.
The four recording heads (head cartridges) 1A of black (B), cyan (C), magenta (M), and yellow (Y) on the carriage 2 are formed by the suction recovery means consisting of
The suction recovery of 1D is sequentially performed.
Then, the ink sucked from the recording head 1 by the suction pump 16 is sent to a waste ink tank (not shown) and discharged through a tube, an ink flow path, or the like. This waste ink tank may be composed of a porous ink absorber that absorbs and holds the waste ink (such as the waste ink absorber 38 in FIG. 5). Therefore, in addition to the suction cap 41, the same number of protective (storage for leaving) caps 42 as the recording head 1 are provided. The number of the protective caps 42 may be one less than that of the recording head 1 when the suction caps 41 are used as protective caps. Therefore, a porous ink absorber 55 is filled inside the suction cap 41.

In FIG. 18, the capacity of the porous ink absorber 52 is larger than the suction amount of the suction pump 16 (forced discharge amount of ink in one operation) or the ink of the recording head 1 as described above. It is set to a value larger than the internal volume of the flow path. When the suction recovery of a large number of recording heads 1 is performed by one cap (suction cap) 41 as shown in FIG. 18, the capacity of the ink absorber 55 loaded in the cap 41 is set as described above. By making the suction amount of the suction pump 16 or the inner volume of the ink flow path of the recording head 1 larger than the residual ink on the ejection port surface 81 after the suction recovery, the ink at the ejection port 82 of each recording head 1 is eliminated. It is possible to prevent color mixing.

For example, when the suction recovery of the cyan recording head 1B is performed after the black recovery of the black recording head 1A, as described in the third embodiment of FIG.
Almost all of the suction ink of the black recording head 1A
It is taken to the ink absorber 55 side in the cap, and is further sent to the waste ink tank side. Then, the ink in the ink absorber 55 is sent to the waste ink tank side by a predetermined operation (such as empty suction), whereby the ink absorption capacity of the ink absorber 55 is restored to a value close to the initial value.

After that, absorption and recovery of the next cyan recording head 1B is performed. At this time, since the suction cap 41 is filled with the predetermined volume of the ink absorber 55, the ink flow in the cap 41 is directional (direction from the recording head 1B side to the suction pump 16 side). Therefore, even if the previous black ink remains in the ink absorber 55, this black ink is used for the cyan recording head 1B.
Therefore, the problem of color mixing in which black ink mixes with cyan ink is reliably prevented without going to the side and therefore without penetrating into the ejection port 82 of the recording head 1B. Further, since the ink between the recording head 1B and the suction cap 41 is carried to the ink absorber 55 side in the cap as described in the third embodiment (FIG. 17), it is scattered by wiping or the like. Even when the different-color ink adheres to the ejection port surface 81 of the recording head 1B, the problem of color mixture in which the different-color ink mixes with the ink (cyan ink) of the recording head 1B is surely prevented.

Therefore, according to the present embodiment, as shown in FIG. 18, the suction of a plurality of recording heads 1 is performed by a simple and small suction recovery means composed of one suction cap 41 and one suction pump 16. Even when recovery is performed, each recording is performed with a simple configuration in which the suction cap 41 is filled with the ink absorber 55 having a volume larger than the suction amount of the pump 16 or the internal volume of the ink flow path of the recording head 1. Head 1
It is possible to reliably solve the problem of ink color mixing when performing suction recovery of. Further, this makes it possible to reduce the cost of the inkjet recording apparatus.

According to the third or fourth embodiment described with reference to FIGS. 12 to 18 above, the suction amount of the pump 16 or the recording head 1 in the caps 15, 41 used for suction recovery.
The porous ink absorbers 52 and 55 having an ink absorption capacity larger than the inner volume of the ink flow path of the ink head, the ink on the ejection port surface 81 by sliding on the ejection port surface 81 of the recording head 1, and the like. A wiping blade 18 for wiping off and cleaning the attached matter, a blade cleaner 51 disposed substantially on the same plane as the discharge port surface 81 for cleaning the wiping blade 18 by rubbing the wiping blade 18, and a wiping blade in a capping state. A suction pump 16 for forcibly sucking the ink from the ejection port 82 of the recording head 1 is provided, and further, a separation mechanism that separates the suction caps 15 and 41 from the recording head 1 at a predetermined timing, and an ink absorber in the cap. Since a mechanism for discharging the ink held in 52 and 55 to the waste ink tank is provided, it is possible to perform the recording operation after the suction recovery. The ink remaining on the ejection port surface 81 of the nozzle 1 can be eliminated, the load on the wiping blade 18 and the blade cleaner 51 can be reduced, and their life can be extended. An ink jet recording apparatus capable of stably maintaining ink ejection performance and image quality for a long period of time by eliminating defects and twists and capable of reliably preventing ink color mixture in color recording was obtained. .

That is, according to the above-described third or fourth embodiment, the ink absorbers 52, 55 are loaded in the caps 15, 41 for performing suction recovery of the recording head 1, and the ink absorbers are loaded. Since the ink absorption capacities of 52 and 55 are set to a value larger than the forced discharge amount of one operation of the suction pump 16 or the inner volume of the ink flow path of the recording head 1, the ejection volume of the recording head 1 is recovered after suction recovery. By almost eliminating the residual ink adhering to the outlet surface 81, it is possible to prevent the performance deterioration of the wiping blade 18 and the blade cleaner 51, stabilize the ink ejection of the recording head 1, and perform good recording for a long time. In addition, with a simple structure, it is possible to reliably prevent color mixture of ink when using a plurality of recording heads 1 for color recording. An ink jet recording apparatus is obtained such.

In each of the above-described embodiments, the case where the replaceable head cartridge in which the recording head and the ink tank are integrated is used as the recording means has been described as an example. However, the present invention is not limited to this. The present invention can be similarly applied regardless of the arrangement of the recording head and the ink tank, such as a case where the tank is provided separately, and the same effect can be achieved. Further, in the above-described embodiment, the color recording apparatus using a plurality of recording heads for recording with different color inks has been described as an example, but the present invention is a recording apparatus using one recording head or the same color. It can be similarly applied to any number of recording heads and inks used, such as a recording apparatus for gradation recording using a plurality of recording heads that record with inks having different densities, and the same effects can be obtained. It can be achieved.

Further, in the above-described embodiment, the recording head 1
Although the description has been given by taking as an example the case of a serial type recording device in which the carriage 4 is mounted on the carriage 4, the present invention relates to The same can be applied to the case, and the same effect can be obtained.

The present invention can be applied to an ink jet recording apparatus using a recording means (recording head) using an electromechanical transducer such as a piezo element, but among them, thermal energy is used. In this way, an excellent effect is brought about in an ink jet recording apparatus of the type that ejects ink. This is because such a system can achieve high density recording and high definition recording.

Regarding its typical structure and principle, see, for example, US Pat. Nos. 4,723,129 and 4740.
This is preferably done using the basic principles disclosed in 796. This method can be applied to both the so-called on-demand type and the continuous type, but particularly in the case of the on-demand type, a liquid (ink) is used.
By applying at least one drive signal to the electrothermal converter arranged corresponding to the sheet or liquid path in which is stored, which corresponds to the recorded information and causes a rapid temperature rise exceeding nucleate boiling. , Generates heat energy in the electrothermal converter to cause film boiling on the heat acting surface of the recording means (recording head), and as a result, bubbles can be formed in the liquid (ink) in a one-to-one correspondence with this drive signal. So effective.

Due to the growth and contraction of the bubbles, the liquid (ink) is ejected through the ejection openings to form at least one droplet. It is more preferable to make the driving signal into a pulse shape because bubbles can be grown and contracted immediately and appropriately, and thus a liquid (ink) with excellent responsiveness can be ejected. As this pulse-shaped drive signal, US Pat.
Those described in US Pat. Nos. 4,633,359 and 4,345,262 are suitable. Incidentally, US Pat. No. 43131 of the invention relating to the rate of temperature rise of the heat acting surface
If the conditions described in the specification of No. 24 are adopted, more excellent recording can be performed.

As the constitution of the recording head, in addition to the combination constitution of the ejection port, the liquid passage, and the electrothermal converter (the linear liquid passage or the right-angled liquid passage) as disclosed in the above-mentioned specifications, US Pat. No. 4,558,333, US Pat. No. 4,558,333, which discloses a configuration in which a heat acting portion is arranged in a bending region.
A configuration using the specification of No. 459600 is also included in the present invention. In addition, Japanese Laid-Open Patent Publication No. 123670/1984 discloses a configuration in which a common slit is used as a discharge portion of the electrothermal converter for a plurality of electrothermal converters, and an opening for absorbing a pressure wave of thermal energy. The present invention is also effective as a structure based on Japanese Patent Laid-Open No. 138461/1984, which discloses a structure in which the discharge section is associated with the discharge section. That is, according to the present invention, recording can be reliably and efficiently performed regardless of the form of the recording head.

Further, as described above, the present invention can be effectively applied to a full line type recording head having a length corresponding to the maximum width of a recording material (recording medium) which can be recorded by the recording apparatus. . As such a recording head,
Either a structure that satisfies the length by combining a plurality of recording heads or a structure as one recording head integrally formed may be used. In addition, even with the serial type as in the above example, the recording head fixed to the device main body,
Alternatively, a replaceable chip-type recording head that can be electrically connected to the device body and supply ink from the device body when mounted on the device body, or an ink tank is integrally provided on the recording head itself. The present invention is also effective when the cartridge type recording head described above is used.

Further, it is preferable to add recovery means or preliminary auxiliary means to the recording head provided as the constitution of the recording apparatus in the present invention because the effect of the present invention can be further stabilized. Specific examples thereof include capping means, cleaning means, pressurizing or suctioning means, electrothermal converters or heating elements other than these, or preheating means for the recording head. It is also effective to perform stable recording by performing a preliminary discharge mode in which discharge different from recording is performed.

As described above, regarding the type and number of recording heads to be mounted, for example, only one is provided corresponding to a single color ink, or a plurality of recording heads having different recording colors and densities are provided. A plurality of inks may be provided corresponding to the ink. That is, for example, the recording mode of the recording apparatus is not limited to the recording mode of only the mainstream color such as black, but may be either the recording head is integrally configured or a combination of a plurality of recording heads may be used. The present invention is extremely effective for an apparatus provided with at least one of color colors or full colors by color mixing.

In addition, in the above-described embodiments of the present invention, the ink is described as a liquid, but it is an ink which solidifies at room temperature or lower and softens or liquefies at room temperature, or an ink jet. In the method, the temperature of the ink itself is generally adjusted within a range of 30 ° C. or higher and 70 ° C. or lower to control the temperature of the ink so that the viscosity of the ink is within a stable ejection range. It may be in a liquid form. in addition,
Whether the temperature rise due to thermal energy is positively used as the energy for changing the state of the ink from the solid state to the liquid state, or the ink that solidifies when left standing for the purpose of preventing evaporation of the ink is used. In any case, the ink is liquefied by applying the thermal energy according to the recording signal and the liquid ink is ejected,
The present invention is also applicable to the case of using an ink that has a property of being liquefied only by thermal energy, such as one that has already started to solidify when it reaches the recording medium.

The ink in such a case is described in JP-A-54-
As described in JP-A-56847 or JP-A-60-71260, a mode in which it is held as a liquid or a solid in the recesses or through holes of the porous sheet and faces the electrothermal converter. May be In the present invention, the most effective one for each of the above-mentioned inks is to execute the above-mentioned film boiling method.

In addition, as the form of the ink jet recording apparatus according to the present invention, besides the one used as an image output terminal of information processing equipment such as a computer, a copying apparatus combined with a reader or the like, and a facsimile apparatus having a transmitting / receiving function. And the like may be used.

[0092]

As is apparent from the above description, according to the invention of claim 1, in the ink jet recording apparatus for recording by ejecting ink from the recording means to the recording material,
Since a plurality of recording means and suction recovery means are provided and an operation sequence for selectively performing suction recovery of only a certain recording means is adopted, the amount of waste ink is reduced and the waste ink storage section is downsized and recording is performed. The device itself is also miniaturized, wasteful ink consumption is reduced, cost is reduced, discomfort for users who use only specific recording means is eliminated, and ink composition used in each recording means is reduced. There is provided an inkjet recording device capable of setting a suction amount, a suction interval, an initial suction pressure, and the like corresponding to the difference.

According to the inventions of claims 2 to 4, in addition to the above-mentioned constitution, the constitution is such that the necessity of suction recovery is detected at a predetermined timing, and only a specific recording means is suction recovered according to the result. The initial suction pressure, the amount of suction, the suction interval, and other suction conditions are individually set for the recording unit, or the recording unit that is not used is not suctioned. Can be achieved.

According to the invention of claim 7, in an ink jet recording apparatus for recording by ejecting ink from the recording means to the recording material, the ejection port of the recording means is covered with a cap and the ink is forcibly forced from the ejection port. The recovery means for discharging is provided, and the capacity of the ink absorber provided in the cap is larger than the discharge amount in one operation of the recovery means. Therefore, the ink adhering to the ejection port surface of the recording means is removed as much as possible. By this, it is possible to prevent the performance of the wiping unit from deteriorating, stabilize the ink ejection of the recording unit, perform good recording for a long time, and prevent the color mixture of the inks when using a plurality of recording units. A recording device is provided.

According to the inventions of claims 8 and 9,
In addition to the above configuration, the recovery unit is configured to perform forced discharge of ink by a suction operation, or the suction operation is terminated by opening the cap at a predetermined timing, so that the above effect is achieved more efficiently. be able to.

According to the twelfth aspect of the invention, in the ink jet recording apparatus for recording by ejecting ink from the recording means to the recording material, the ejection port of the recording means is covered with a cap and the ink is forcibly ejected from the ejection port. Since the ink absorber provided in the cap has a capacity for discharging and the capacity of the ink absorber is larger than the inner volume of the ink flow path of the recording means, the ink adhering to the ejection port surface of the recording means is removed as much as possible. By this, it is possible to prevent the performance of the wiping unit from deteriorating, stabilize the ink ejection of the recording unit, perform good recording for a long time, and prevent the color mixture of the inks when using a plurality of recording units. A recording device is provided.

According to the inventions of claims 13 to 16,
In addition to the above-described configuration, a configuration in which the recovery unit forcibly discharges ink is performed by a suction operation, a configuration in which the suction operation is ended by opening the cap at a predetermined timing, and the amount of ink discharged by the recovery unit is the ink of the recording unit. Since the structure is larger than the inner volume of the flow path or the amount of ink discharged by the recovery means is smaller than the capacity of the ink absorber in the cap, the above effect can be achieved more efficiently.

[Brief description of drawings]

FIG. 1 is a partially cutaway perspective view showing a schematic configuration of an embodiment of an inkjet recording apparatus to which the present invention is applied.

FIG. 2 is a schematic perspective view of the head cartridge in FIG.

FIG. 3 is a partial perspective view schematically showing the structure of an ink ejection portion of the recording means in FIG.

FIG. 4 is a schematic vertical sectional view of an ink ejection portion of the recording unit in FIG.

5 is a vertical cross-sectional view showing the structure and operation of the suction pump in FIG.

FIG. 6 is a schematic front view showing a state before color designation of the first embodiment of the suction recovery means of the inkjet recording apparatus to which the present invention is applied.

7 is a schematic front view showing a state before suction when the cyan color of the suction recovery means of FIG. 6 is designated.

8 is a schematic front view showing a state during a suction operation when the cyan color of the suction recovery means of FIG. 6 is designated.

9 is a schematic front view showing a state in which each recording head is capped after the suction operation is completed by the suction recovery means in FIG.

FIG. 10 is a schematic front view showing the configuration and operation of the second embodiment of the suction recovery means of the inkjet recording apparatus to which the present invention is applied.

11 is a flowchart showing an example of a recovery operation sequence of the ink jet recording apparatus having the suction recovery means of FIG.

FIG. 12 is a bottom view of the carriage in FIG.

FIG. 13 is a front view of the carriage in FIG.

FIG. 14 is a schematic front view illustrating a state in which ink droplets are attached to the ejection port surface of the recording unit.

FIG. 15 is a schematic front view illustrating a state in which ink remains on the ejection port surface of the recording unit.

16 is a schematic front view showing a wiping operation of a recording unit and a cleaning operation of a blade in FIG. 1. FIG.

FIG. 17 is a schematic partial sectional view for explaining the operation of the third embodiment of the suction recovery means of the inkjet recording apparatus to which the present invention has been applied.

FIG. 18 is a schematic front view showing the configuration and operation of the fourth embodiment of the suction recovery means of the inkjet recording apparatus to which the present invention has been applied.

FIG. 19 is a schematic partial cross-sectional view for explaining the operation of the suction recovery unit of the conventional inkjet recording apparatus.

[Explanation of symbols]

 1 Recording Means (Recording Head = Head Cartridge) 2 Carriage 3 Guide Shaft 4 Main Scanning Motor 7 Timing Belt 8 Recording Material 9 Conveying Roller 13 Ink Discharging Section (Recording Means) 14 Recovery System Unit 15 Cap (Cap Unit) 16 Suction Pump 17 Blade Holder 18 Wiping Blade 19 Tube 21 Ink Tank 22 Recording Head 24 Heater Board (Recording Means) 26 Wiring Board 27 Bubble 28 Ink Droplet 31 Piston Shaft 33 Piston 34 Pump Chamber 35 Cylinder 36 Cap Lever 37 Piston Receiver 38 Waste Ink Absorption Body 41 Suction Cap 42 Protection Cap 43 Control Panel 44 Suction Switch 45 Color Designation Switch 51 Blade Cleaner (Ink Absorber) 52 Ink Absorber 53 Link 54 gap 55 ink absorber

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[Procedure amendment]

[Submission date] August 5, 1994

[Procedure Amendment 1]

[Document name to be corrected] Drawing

[Correction target item name] All drawings

[Correction method] Change

[Correction content]

[Figure 4]

[Figure 1]

[Fig. 2]

[Figure 3]

[Figure 5]

[Figure 6]

[Figure 7]

FIG. 14

[Figure 8]

[Figure 9]

[Fig. 12]

FIG. 15

[Figure 10]

[Fig. 13]

FIG. 11

FIG. 16

FIG. 17

FIG. 18

FIG. 19

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Hitoshi Sugimoto 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Miyuki Matsubara 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon (72) Inventor Hiromitsu Hirabayashi 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Norifumi Koitabashi 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc.

Claims (18)

[Claims] 1. An ink jet recording apparatus for recording by ejecting ink from a recording means to a recording material, wherein a plurality of recording means and suction recovery means are provided, and suction recovery of only a certain recording means is performed. An inkjet recording apparatus having a sequence. 2. The ink jet recording apparatus according to claim 1, wherein whether or not the suction recovery is necessary is detected at a predetermined timing, and only the specific recording means is suction recovered according to the result. 3. The ink jet recording apparatus according to claim 1, wherein suction conditions such as an initial suction pressure, a suction amount, and a suction interval are individually set for each recording unit. 4. The ink jet recording apparatus according to claim 1, wherein suction is not applied to unused recording means. 5. The ink jet recording apparatus according to claim 1, wherein the recording means is an ink jet recording means provided with an electrothermal converter that generates thermal energy used for ejecting ink. 6. The ink jet recording apparatus according to claim 5, wherein the ink jet recording means ejects the ink from the ejection port by utilizing the film boiling generated in the ink by the thermal energy generated by the electrothermal converter. . 7. An ink jet recording apparatus for recording by ejecting ink from a recording means to a recording material, comprising a recovery means for covering a discharge port of the recording means with a cap and forcibly discharging the ink from the discharge port. An ink jet recording apparatus, wherein a capacity of an ink absorber provided in the cap is larger than a discharge amount in one operation of the recovery means. 8. The ink jet recording apparatus according to claim 7, wherein the recovery unit forcibly discharges the ink by a suction operation. 9. The ink jet recording apparatus according to claim 8, wherein the suction operation is ended by opening the cap at a predetermined timing. 10. The ink jet recording apparatus according to claim 7, wherein the recording means is an ink jet recording means provided with an electrothermal converter that generates thermal energy used for ejecting ink. 11. The ink jet recording apparatus according to claim 7, wherein the ink jet recording means ejects the ink from the ejection port by utilizing film boiling generated in the ink by the thermal energy generated by the electrothermal converter. . 12. An ink jet recording apparatus for recording by ejecting ink from a recording means to a recording material,
The recording medium has a recovery means for covering the ejection port with a cap and forcibly ejecting ink from the ejection port, and the capacity of the ink absorber provided in the cap is larger than the inner volume of the ink flow path of the recording means. An ink jet recording apparatus characterized by the above. 13. The ink is forcibly discharged by the recovery means by a suction operation.
2. Inkjet recording device. 14. The ink jet recording apparatus according to claim 13, wherein the suction operation is ended by opening the cap at a predetermined timing. 15. The ink jet recording apparatus according to claim 12, wherein the amount of ink discharged by the recovery means is larger than the inner volume of the ink flow path of the recording means. 16. The ink jet recording apparatus according to claim 12, wherein the amount of ink discharged by the recovery means is smaller than the capacity of the ink absorber in the cap. 17. The ink jet recording apparatus according to claim 12, wherein the recording means is an ink jet recording means provided with an electrothermal converter that generates thermal energy used for ejecting ink. 18. The ink jet recording apparatus according to claim 17, wherein the ink jet recording means ejects the ink from the ejection port by utilizing the film boiling generated in the ink by the thermal energy generated by the electrothermal converter. .