JP2003001858A - Ink jet recorder and recovery system unit thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent ink mixed with black ink from adhering to a vicinity of a color-ink discharge opening, and prevent the quality of a recorded image from being degraded by a color mixture of the ink in recording after empty suction, when the empty suction is applied to a recording head, having a black- ink discharge opening and the color-ink discharge opening, in such a manner that a single cap and a single suction means make negative pressure act on the inside of the cap communicating with the atmosphere. SOLUTION: A suction port 21 for making the negative pressure from a negative-pressure generating source act on the inside of the cap is arranged in a position closer to the black-ink discharge opening of a recording means, facing the cap in capping, than to the color-ink discharge opening of thereof; and a communicating port 22 for making the inside of the cap communicate with the atmosphere is arranged in or near a position which is within an area of the color-ink discharge opening of the recording head, facing the cap in the capping, and farthest away from the black-ink discharge opening.

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 having a black ink ejection port and a color ink ejection port to a recording medium, and a recovery system unit of the apparatus.

[0002]

2. Description of the Related Art A recording device having functions such as a printer, a copying machine and 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. An image (including characters and symbols) is recorded on a recording medium (recording material) such as a cloth, a plastic sheet, and an OHP sheet. 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 for recording while performing main scanning in a direction intersecting the conveyance direction (paper feeding direction, sub-scanning direction) of the recording medium, on a carriage moving along the recording medium (main scanning). An image is recorded by a recording head as a recording unit installed, a predetermined amount of paper is fed (pitch conveyance as sub-scanning) after the recording of one line is completed, and then the recording medium stopped again is moved to the next recording medium. The entire recording medium is printed by repeating the operation of printing (main scanning) the image of the line. On the other hand, in a line type recording apparatus that records only by sub-scanning in the conveyance direction of a recording medium (recording material), after the recording medium is set at a predetermined recording position and one line of recording is collectively performed. By repeating the operation of feeding a predetermined amount of paper (pitch feeding) and then collectively printing the next line, printing of the entire printing medium is performed.

Among them, the ink jet type recording apparatus (ink jet recording apparatus) is one which performs recording by ejecting ink from an ink jet head as a recording means to a recording medium, and the recording means can be easily made compact and high. High-definition images can be recorded at high speed, plain paper can be recorded without any special processing, running costs are low, and the non-impact method produces less noise, and a large variety of inks It has an advantage that it is easy to record a color image using (for example, color ink). In addition, in the ink jet recording apparatus, there are various requirements for the material of the recording medium (recording material), and in recent years, the development of these requirements has advanced, and paper (thin paper or processed paper) which is a normal recording medium has been developed. In addition to (including) and resin thin plates (OHP, etc.), recording devices using cloth, leather, non-woven fabric, and metals as recording media have also been used.

An ink jet recording apparatus performs recording (image formation, printing, printing, etc.) by ejecting ink supplied to a recording head (ink jet head) toward a recording medium such as paper by heating or vibration. It is configured. In this type of ink jet recording apparatus, when the apparatus is not used for a long period of time, the recording head as a recording unit is protected, ink evaporation near the ejection port of the recording head is prevented, and ink adheres near the ejection port. A recovery system unit (cleaning unit) for maintaining and recovering the ink ejection performance of the recording head is generally prepared in order to remove the fixed ink. This recovery system unit is usually a negative pressure such as a capping unit that is in close contact with the ejection port surface of the recording head to cover the ejection port, and a suction pump that is connected to the capping unit to generate a negative pressure in the cap. It is composed of a generation source and a wiping means for wiping off (cleaning) ink or the like adhering to the ejection port surface of the recording head.

Recently, in order to make the structure of the printing apparatus compact and simple, a plurality of black ink ejection port arrays and color ink ejection port arrays are arranged on one ejection port surface of the recording head, and a recovery process is performed. At this time, there has been proposed a configuration (collective suction type) in which the black ink discharge port array group and the color ink discharge port array group are capped by one cap and a suction operation is performed by one suction pump. On the other hand, as a sequence of the recovery processing of the recording head by the recovery system unit, after performing a suction recovery operation in which the suction pump is operated in a capping state in which the ejection port is sealed by a cap to suck ink from the ejection port, A sequence is adopted in which the suction pump is operated again after communicating with the atmosphere to suck and remove the residual ink in the cap.

[0007]

However, in the conventional ink jet recording apparatus, one cap is provided for a recording head in which a plurality of black ink ejection port arrays and color ink ejection port arrays are arranged on one ejection port surface. Also, when a single suction pump is used and immediately after performing the suction recovery operation by sealing the discharge opening with the cap, the black ink discharge opening is used when performing the empty suction operation in which the inside of the cap is communicated with the atmosphere and further suctioned. Ink adhering to the periphery of the (ejection port array) causes color ink ejection ports (ejection port array) by the air flow in the cap.
Area, and the mixed color ink in which the black ink is mixed with the color ink remains and adheres in the vicinity of the color ejection port.In such a state, the mixed color ink that adheres after the idle suction operation enters the color ejection port. Since the mixed color ink with the black ink is ejected from the color ejection port at the start of recording after invasion and idle suction, there is a technical problem that the quality of the initial recorded image is significantly deteriorated.

The present invention has been made in view of the above technical problems, and an object of the present invention is to provide a single cap and a single suction for a recording head having a black ink ejection port and a color ink ejection port. By means of the means, it is possible to prevent the mixed ink with the black ink from adhering to the periphery of the color discharge port when performing negative suction by applying a negative pressure in the cap that is in communication with the atmosphere. It is an object of the present invention to provide an inkjet recording device and a recovery system unit that can prevent deterioration of the quality of a recorded image due to ink color mixing.

[0009]

The present invention (Claim 1) includes:
In order to achieve the above object, in an inkjet recording apparatus for recording by ejecting ink from a recording means having a black ink ejection port and a color ink ejection port to a recording medium, a single black ink ejection port and a color ink ejection port are provided. The cap is provided with an empty suction means for communicating the inside of the cap with the atmosphere and applying a negative pressure from a negative pressure generating source to the inside of the cap to suck and remove the residual ink in the cap. The suction port for applying a negative pressure from the pressure generation source is formed at a position closer to the black ink ejection port than the color ink ejection port of the recording means facing at the time of capping, and is a communication port for communicating with the atmosphere in the cap. Mouth is
It is characterized in that it is arranged at a position most distant from the black ink ejection port or in the vicinity thereof in the area of the color ink ejection port of the recording head facing at the time of capping.

In order to achieve the above-mentioned object, another invention of the present invention (claim 8) is an ink jet recording apparatus for recording by ejecting ink from a recording means having a black ink ejection port and a color ink ejection port onto a recording medium. In the recovery system unit, the black ink ejection port and the color ink ejection port are covered with a single cap, the inside of the cap is communicated with the atmosphere, and a negative pressure from a negative pressure generation source is applied to the inside of the cap. A suction port for applying a negative pressure from a negative pressure source to the inside of the cap, and a black ink ejection port from a color ink ejection port of the recording device facing at the time of capping. A communication port formed at a position closer to the cap for communicating with the atmosphere in the cap is provided in the area of the color ink discharge port of the recording head facing at the time of capping. Characterized in that it is arranged at the farthest position or the vicinity thereof from the black ink discharge port I.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be specifically described below with reference to the drawings. The same reference numerals denote the same or corresponding parts throughout the drawings. FIG. 1 is a schematic perspective view showing the overall configuration of an embodiment of an inkjet recording apparatus to which the present invention is applied. In FIG. 1, a carriage 1 is equipped with a recording head 7 as recording means, and a chassis 3 constituting the apparatus main body is provided with a carriage guide support mechanism composed of a guide shaft 2 and a guide rail 4 extending in the left-right direction. The carriage 1
Are guided and supported along the carriage guide support mechanism so as to be capable of reciprocating. The carriage 1 includes a chassis 3
By the forward and reverse rotations of the carriage motor 8 fixed to, the carriage motor 8 is reciprocally moved (reciprocatingly driven) via the timing belt 9. A platen 6 for guiding and supporting a recording sheet 10 as a recording medium is installed at a position facing the recording head 7.

Incidentally, the recording head 7 in the present embodiment.
Is a structure in which a recording head portion (ink ejection portion) and an ink tank are integrated, or a structure in which an ink tank is detachably attached to the recording head portion, and is replaceably mounted on the carriage 1. There is. This recording head 7
Constitutes a so-called head cartridge. An automatic paper feeding unit 14 is attached to the recording apparatus, and the recording paper 10 fed into the recording apparatus from the automatic paper feeding unit 14 conveys a recording medium to a conveyance roller (paper feeding motor). The recording sheet 10 conveyed by the paper feed roller 5 through the recording unit and recorded is ejected out of the apparatus main body by a paper ejection roller 12 and a pinch roller 11 which rotate in synchronization with the conveyance roller 5.

In recording, after the recording sheet 10 fed to the recording section facing the recording head 7 is set at the recording start position, the carriage 1 is accelerated from a stopped state and moved at a constant speed. At this time, the recording head 7 on the carriage 1 is driven based on the recording data transmitted to the recording apparatus to eject ink from the recording head toward the recording paper 10 to record one line. When the recording for one line is completed, the carriage 1 is decelerated and stopped. After recording one line,
The conveyance roller (paper feed roller) 5 is rotated by a predetermined amount, and the recording paper 10 is conveyed (paper feed) to a position where the portion where the next line of the recording paper 10 should be recorded faces the recording head 7. After the carrying operation is completed, the carriage 1 is moved again and the recording of the next line is performed during this movement.

Thereafter, the recording paper 10 is recorded by alternately repeating the recording for each line and the paper feeding for one line.
The entire recording of the data or all the specified recording data is recorded. Recording sheet 10 thus recorded
Is discharged to the outside of the recording apparatus by the paper discharge roller 12. With the above, recording on the recording sheet 10 is completed.
In the inkjet recording apparatus shown in FIG. 1, the recording head 7 is located at a predetermined position (the right end portion in the illustrated example) outside the recording area (for example, recording paper having the maximum width) within the moving area of the carriage 1. A recovery system unit 13 for maintaining and recovering the ink ejection performance of is provided.

The recording head (inkjet head) 7 as the recording means is an inkjet recording means for ejecting ink by utilizing thermal energy, and is provided with an electrothermal converter for generating thermal energy. is there. Further, the head 7 causes film boiling in the ink by the thermal energy applied by the electrothermal converter, and ejects the ink from the ejection port by utilizing the pressure change due to the growth and contraction of bubbles generated at that time. , Recording (printing) is performed.

FIG. 7 is a partial perspective view schematically showing the structure of the ink ejection portion of the ejection port array having the recording head 7. In FIG. 7, the ejection port surface 81 facing the recording medium 10 such as a recording sheet with a predetermined gap (for example, about 0.2 to about 2.0 mm) has a plurality of ejection ports at a predetermined pitch. 8
2 is formed, and an electrothermal converter (heating resistor or the like) 85 for generating energy for ejecting ink along the wall surface of each liquid passage 84 that connects the common liquid chamber 83 and each ejection port 82.
Is provided. The recording heads 7 are mounted on the carriage 1 in such a positional relationship that the ejection openings 82 are arranged in a direction intersecting the main scanning direction (the moving direction of the recording head 7 and the carriage 1). In this way, the corresponding electrothermal converter 85 is driven (energized) based on the image signal or the ejection signal to cause the ink in the liquid passage 84 to film-boil, and the ink generated from the ejection port 82 is ejected by the pressure generated at that time. An inkjet recording head (recording means) 7 is configured.

FIG. 2 is a bottom view of the recording head 7 seen from below in order to show the arrangement of a plurality of ejection port arrays on the ejection port surface of the recording head 7 in FIG. In FIG. 2, on the ejection port surface 81 of the recording head 7, a plurality of ejection port arrays for ejecting inks of different colors, that is, a black ink ejection port array 41,
A total of four ejection port arrays, that is, a yellow ink ejection port array 51, a magenta ink ejection port array 52, and a cyan ink ejection port array 53 are formed, and are configured to eject ink by utilizing heat or vibration. ing. Further, as in the present embodiment, the recording head 7 that ejects both black ink and color ink
In general, the plurality of ejection port arrays on the ejection port surface 81 are arranged in parallel with each other as shown in the figure, and
A black ink ejection port array group 40 including the black ink ejection port array 41 (one ejection port array in this embodiment), the yellow ink ejection port array 51, the magenta ink ejection port array 52, and the cyan ink ejection port array 53. And the color ink discharge port array group 50 composed of

FIG. 3 is a schematic vertical sectional view showing a schematic structure of the recovery system unit 13 in FIG. In the inkjet recording apparatus according to this embodiment, the recording head 7 is protected when it is not used (stopped) for a long period of time, ink is prevented from evaporating in the vicinity of the ejection port, or the recording head 7 is solidified in the vicinity of the ejection port. The recovery system unit (cleaning unit) 13 is provided to remove the ink. The recovery system unit 13 mainly includes the discharge port surface 8
1, a cap 15 as a capping means for tightly closing (capping) the discharge port 82, the inside of the cap 15 and the tube 17 are connected, and a negative pressure is generated in the cap to discharge the discharge port 82 from the discharge port 82. And a suction pump for sucking (sucking) the ink. In the normal recovery system unit, the cap 1
In addition to the suction pump 45 and the suction pump 45, a wiping unit is provided for wiping (wiping off, cleaning) the deposits such as ink on the ejection port surface 81.

In a general ink jet recording apparatus having a plurality of ejection port array groups such as a black ink ejection port array group and a color ink ejection port array group, a cap and a suction pump are independent for each ejection port array group. The recording head is maintained under optimum recovery conditions (cleaning conditions). However, such a recovery system unit (cleaning unit) requires at least two caps and two suction pumps, resulting in a large product and an increase in cost. Therefore,
A suction recovery mechanism of a structure in which the black ink discharge port array group and the color ink discharge port array group are sealed with one cap and ink is sucked by a single pump, that is, a so-called collective suction type suction recovery mechanism is proposed. ing.

The recovery system unit 13 shown in FIG. 3 is provided with the collective suction type suction recovery mechanism as described above, and FIG. 3 is a recovery system unit (cleaning unit) having this collective suction type suction recovery mechanism. It is sectional drawing which shows the structure of the cap 15 of 13 and the suction pump 45. In FIG. 3, inside the pump base 20, the pump shaft 1
A roller holder 18 rotatable around 8a is disposed, and the roller holder is rotationally driven in the direction of arrow A by a drive source (not shown). The tube 17 is laid along the semicircular dome-shaped inner wall formed on the inner surface of the pump base 20. The roller holder 18 has a disk shape, and pressure rollers 19a and 19b are rotatably (rotatably) pivotally supported at diametrically opposed positions (two positions).

One end of the tube 17 (end on the cap side) communicates with the inside of the cap 15 through the through hole of the cap holder 16. The other end of the tube 17 (the end on the opposite side after passing the suction pump 45)
Is a discharge part for discharging the sucked ink, and is connected to, for example, a waste ink storage part filled with an ink absorber. Further, the suction pump 45 is connected to the cap 15 through a communication port 22 for communicating with the atmosphere and a tube 17.
And a suction port 21 communicating with. The communication port 22 is provided with an opening / closing valve 23. The on-off valve 23 is biased by a valve spring 24 in a direction to close the communication port 22.

The pressure rollers 19a and 19b are arranged so as to crush the tube 17 at a position facing the dome-shaped inner wall of the pump base 20,
When the roller holder 18 rotates (revolves), it rolls (rotates) along the tube 17 and squeezes the tube, and when the roller holder 18 comes out of the area of the inner wall of the pump base 20, the tube 17 is released from the ironing. Is configured to. Therefore, the cap 15 is attached to the discharge port surface 8
When the roller holder 18 is rotated in the direction of arrow A in the state where the roller holder 18 is brought into close contact with 1 and the communication port 22 is closed,
Negative pressure is generated in the tube due to the ironing of the tube 17, and this negative pressure passes through the cap 15 and the discharge port 82.
The ink is sucked from the inside of the recording head 7 by acting on the.

Then, the sucked ink (including air)
Flows through the tube 17,
When the tube is released from the ironing and is in communication, it operates to discharge from the other end of the tube. In the illustrated example, one pressure roller 19b rotates together with the roller holder 18 while crushing the tube 17 and does not crush the tube 17 when it comes out of the semicircular dome portion of the pump base 20. Since the pressure roller 19a begins to crush the tube 17,
As long as the roller holder 18 rotates, ink can be continuously sucked.

Immediately after the suction recovery operation is stopped,
The ink sucked into the closed space of the cap 15 is full. Therefore, immediately after the suction recovery operation is completed, the ink filled in the cap 15 is sucked by the suction pump 4
A suction operation (empty suction) of sucking out at 5 is performed. As a general method for performing this idle suction, the on-off valve 23 is opened against the valve spring 23 to bring the communication port 22 into the atmosphere communication state, and the suction pump 45 is used as in the ink suction operation described above. Operate. At that time, a negative pressure is generated in the cap 15, but the atmosphere (air) flows in from the communication port 22 as the negative pressure is generated. Therefore, the recording head 7 (ejection port 82).
Ink is not sucked from the cap 15, and only the ink filled in the cap 15 is sucked together with air by the suction port 21 and the tube 1.
It is sucked through 7 and discharged to the outside through the suction pump 45.

That is, in the illustrated example, the opening / closing valve 23 is rotatably supported by the cap holder 16, and normally the opening / closing valve 23 is capped by the valve spring 24 as shown in FIG. The inside of the cap 15 is shielded (closed) from the atmosphere by coming into contact with the outlet of the communication port 22. When the above-described suction recovery operation is completed, the opening / closing valve 23 is rotated by the driving means (not shown) to open the communication port 22.
The contact with the cap 1 is released, the communication port 22 is opened, and the cap 1
The inside of 5 communicates with the atmosphere. In this state, roller holder 18
Is rotated again in the direction of arrow A, air flows into the inside of the cap 15 from the communication port 22, and the residual ink in the cap 15 is sucked into the cap 15 together with the flowed air.
And suctioned through the tube 17 and the suction pump 4
It is discharged to the outside through 5. After that, the operation of sucking and discharging the ink in the cap 15 in this way is referred to as "empty suction".
Call.

FIG. 4 is a schematic plan view of the cap 15 of the recovery system unit 13 of the ink jet recording apparatus to which the present invention is applied. That is, FIG. 4 shows the positions of the suction port 21 and the communication port 22 when the cap 15 is viewed from the contact surface side with the ejection port surface 81, and the ejection port of the recording head 7 that faces the cap when capping. It is a figure which shows the position of each ejection opening row (each ejection opening row group) on the surface 81 by a two-dot chain line. In FIG. 4, the suction ports 21 provided in the cap 15 are the color ink ejection port array group 50 and the black ink ejection port array group 40 on the ejection port surface 81 facing each other during capping.
It is arranged at a position closer to the black ink ejection port array group 40 than an intermediate point between the and. Further, the communication port 22 provided in the cap 15 is provided with the discharge port surface 8 facing at the time of capping.
It is arranged in a region of the group 50 of color ink ejection openings on the uppermost part 1 or at a position farthest from the group of black ink ejection openings and the vicinity thereof.

Suction port (negative pressure suction port) 2 as shown in FIG.
According to the cap 15 having the arrangement configuration of the communication port 1 and the communication port (atmosphere communication port) 22, the on-off valve 23 is opened to open the inside of the cap 15 to the atmosphere after performing the above-described suction recovery operation of sucking the ink from the ejection port 82. Suction pump 45 in the state of communicating with
When the idle suction is performed by re-operating, the air flow in the cap 15 at that time is in the state shown by the arrow in FIG. That is, since a negative pressure is about to act from the suction port 21 into the cap 15, the air flows in from the communication port 22 and the inflowing air passes through the cap 15 and flows out from the suction port 22 and passes through the tube 17. Since the air is discharged, the air flows in the cap 15 through the path indicated by the arrow in FIG. Therefore, FIG.
As is clear from the drawing, the suction port 2 together with the air flowing in from the communication port 22 and passing through the color ink ejection port array group 50.
The ink carried to 1 passes through the vicinity of the black ink ejection port array group 40 (black ink ejection port array 41 in this embodiment) and is sucked out from the suction port 21 toward the suction pump 45.

However, at that time, the black ink ejection port array group 40
The ink (black ink) carried from the suction port 21 to the suction port 21 is directly sucked out from the suction port 21 without reaching the vicinity of the color ink discharge port array group 50. Therefore, the ink containing the black ink (ink mixed with the black ink) does not adhere to the color ink ejection port array group 50 or the vicinity thereof, and at the time of recording immediately after the suction recovery and idle suction operations (cleaning operation). There is no inconvenience that the black ink is mixed with the color ink and is ejected (at the time of recording immediately after the start of recording) and the image quality of the recorded image is deteriorated. As shown in FIG. 4, mixed color ink in which black ink is mixed with color ink may adhere to the vicinity of the black ink ejection port array group, but even if the color ink is mixed with the black ink, There is almost no effect on the color change for
The problem of deterioration of the quality of the recorded image due to black ink does not occur.

FIG. 5 is a schematic vertical sectional view of a portion including the suction port 21 and the communication port 22 of the cap 15 and the cap holder 16 of FIG. In this embodiment, FIG.
Further, as shown in FIG. 5, at the portion of the communication port 22 for communicating the inside of the cap 15 with the atmosphere, it is integrally formed as a part of the cap 15 from the opening end inside the cap 15 to the opening end outside the cap 15, The pipe portion (the hole portion between the two open ends) has a substantially straight shape downward.

With the structure of the communication port 22 as described above, the ink left in the cap 15 after the idle suction can be easily discharged to the outside when the opening / closing valve 23 is opened at the next opportunity. You can Therefore, the residual ink after the idle suction does not solidify in the cap 15, and it is possible to eliminate the inconvenience such as clogging of the communication port 22 with respect to the idle suction operation performed at the next opportunity. Further, since the communication port 22 is directly opened / closed by the opening / closing valve 23, an extra component such as a connecting tube is not required to form the atmosphere communication means, and the cost can be reduced and the assemblability can be improved. In other words, the ink left in the cap after idle suction can easily flow out from the communication port to the outside, so that residual ink coagulates in the cap or in the communication port, resulting in poor empty suction or coagulation in the communication port. An ink jet recording apparatus capable of eliminating the inconvenience such as clogging due to ink, and further, since it does not require extra parts such as a connecting tube, it is possible to reduce cost and improve assemblability. .

FIG. 6 is a schematic plan view of another embodiment of the cap 15 of the recovery system unit 13 of the ink jet recording apparatus to which the present invention is applied. 6 also shows the positions of the suction port 21 and the communication port 22 when the cap 15 is viewed from the contact surface side with the discharge port surface 81 by the same method as in FIG. 4, and faces the cap at the time of capping. FIG. 6 is a diagram showing the position of each ejection port array (each ejection port array group) on the ejection port surface 81 of the recording head 7 by a chain double-dashed line.

In this embodiment, as shown by the chain double-dashed line in FIG. 6, on the ejection port surface 81 of the recording head 7, the black ink ejection port array group 40 and the color ink ejection port array group 50 are arranged vertically in a line. It is arranged. On the other hand, the suction port 21 provided in the cap 15 is located at a position near the black ink ejection port array group 40 on the ejection port surface 81 facing during capping, that is, as shown in the drawing, the color ink ejection of the black ink ejection port array group 40. The position on the opposite side of the outlet row group 50 or in the vicinity thereof, in other words, in the area of the black ink outlet row group 40 on the ejection port surface 81 of the recording head 7 facing at the time of capping, the color ink ejection ports It is arranged at a position farthest from the row group 50 or in the vicinity thereof. Further, the communication port 22 provided in the cap 15 is located in the region of the color ink ejection port array group 50 on the ejection port surface 81 facing at the time of capping and is at the position farthest from the black ink ejection port array group 40 or its position. It is located in the vicinity.

Suction port (negative pressure suction port) 2 as shown in FIG.
According to the cap 15 having the arrangement configuration of the communication port 1 and the communication port (atmosphere communication port) 22, the on-off valve 23 is opened to open the inside of the cap 15 to the atmosphere after performing the above-described suction recovery operation of sucking the ink from the ejection port 82. Suction pump 45 in the state of communicating with
When the idle suction is performed by re-operating, the air flow in the cap 15 at that time becomes a state shown by an arrow in FIG. That is, since a negative pressure is about to act from the suction port 21 into the cap 15, the air flows in from the communication port 22 and the inflowing air passes through the cap 15 and flows out from the suction port 22 and passes through the tube 17. Since the air is discharged, the air flows in the cap 15 through the path indicated by the arrow in FIG. Therefore, FIG.
As is clear from the drawing, the suction port 2 together with the air flowing in from the communication port 22 and passing through the color ink ejection port array group 50.
The ink carried to 1 passes through the vicinity of the black ink ejection port array group 40 and is sucked out from the suction port 21 toward the suction pump 45.

However, at that time, the black ink ejection port array group 40
The ink (black ink) carried from the suction port 21 to the suction port 21 does not flow to the color ink discharge port array group 50 side, but is directly sucked from the suction port 21. Therefore, the ink containing the black ink (ink mixed with the black ink) does not adhere to the color ink ejection port array group 50 or its vicinity,
As in the case of FIG. 4, at the time of recording immediately after the suction recovery and idle suction operations (cleaning operation) (at the time of recording immediately after the start of recording).
In, black ink is mixed with color ink and ejected,
There is no inconvenience that the image quality of the recorded image deteriorates. Note that in FIG. 6 as well, although mixed color ink in which black ink is mixed with color ink may adhere to the vicinity of the black ink ejection port array group, even if color ink is mixed with black ink, the black ink Has almost no effect on the change in color, so that the problem of deterioration of the quality of the recorded image due to black ink does not occur.

In the embodiment described above, the black ink ejection port 51 and the color ink ejection port are used in the ink jet recording apparatus for recording by ejecting the ink from the recording means having the black ink ejection port and the color ink ejection port to the recording medium. Cover the outlets 51, 52, 53 with a single cap 15,
The cap is provided with an empty suction means for communicating with the atmosphere and applying a negative pressure from the negative pressure generation source 45 to the suction inside the cap to remove residual ink in the cap. The suction port 21 for applying a negative pressure from is formed at a position closer to the black ink ejection port than the color ink ejection port of the recording means 17 facing at the time of capping, and is a communication port for communicating the inside of the cap with the atmosphere. Two
The reference numeral 2 is configured to be arranged in a region of the color ink ejection port of the recording head 17 which faces at the time of capping, and at a position farthest from the black ink ejection port or in the vicinity thereof.

Further, in the embodiment of FIG. 4, a black ink ejection port array 41 composed of a plurality of black ink ejection ports and a color ink ejection composed of a plurality of color ink ejection ports are formed on the ejection port surface 81 of the recording means 7. The outlet rows 51, 52, 53 are arranged in parallel with each other and are divided into a black ink ejection opening row group 40 and a color ink ejection opening row group 50. On the other hand, in the embodiment of FIG. 6, the ejection port surface 81 of the recording means 7 has a black ink ejection port array group 41 composed of a plurality of black ink ejection ports and a color ink ejection port array composed of a plurality of color ink ejection ports. The groups 51, 52, 53 are arranged in a vertical row.

Further, in the embodiment of FIG. 6, the suction port 21 is within the area of the black ink ejection port array group 40 on the ejection port surface of the recording head 7 facing at the time of capping, and is the color ink ejection port array. It is arranged at a position farthest from the group 50 or in the vicinity thereof. Further, in each of the above-described embodiments, the communication port 22 is formed by a vertically straight through hole integrally formed as a part of the cap at the bottom of the cap 15, and the lower end of the communication port is formed. The opening / closing valve 23 is configured to open and close.

According to the above-described embodiment, the recording head 17 having the black ink ejection port and the color ink ejection port.
On the other hand, when the single cap 15 and the single suction unit 45 apply a negative pressure to the inside of the cap that communicates with the atmosphere to perform idle suction, the mixed ink with the black ink adheres to the periphery of the color ejection port. There is provided an ink jet recording apparatus and a recovery system unit capable of preventing such deterioration and preventing deterioration of the quality of a recorded image due to color mixing of ink when recording after idle suction. Further, according to the above-described embodiment, the communication port 22 is a vertically straight through-hole integrally formed at the bottom of the cap 15 as a part of the cap, and the lower end of the communication port is Since the on-off valve 23 is configured to open and close, the ink remaining in the cap after empty suction can be easily flown out from the communication port to the outside, so that the residual ink is solidified in the cap or the communication port and becomes empty. It is possible to eliminate inconveniences such as poor suction and clogging of the communication port with coagulated ink.
Since it does not require extra parts such as connecting tubes,
It is also possible to obtain the effects of being able to reduce costs and improve assemblability.

In the above embodiments, the case of the serial type ink jet recording apparatus for recording while moving the recording head as the recording means in the main scanning direction has been described as an example. In the case of a line-type inkjet recording apparatus that records only by sub-scanning using a line-type inkjet head having a length that covers the entire width or a part of the above, the same effect can be achieved. I will get it. Further, the present invention is an ink jet recording apparatus that uses a recording head having a plurality of ejection port arrays on the same ejection port surface, regardless of the number of recording heads, and uses one or a plurality of recording heads. The same applies to the case of a color inkjet recording apparatus for recording with a plurality of different colors, an inkjet recording apparatus for gradation recording for recording with a plurality of different densities of the same color, and an inkjet recording apparatus combining these. It can be applied and the same effect can be achieved.

Further, according to the present invention, a structure using an exchangeable ink jet cartridge in which a recording head and an ink tank are integrated, a structure using a recording means for detachably mounting the ink tank on the recording head, or a recording head is used. It can be applied to any case where the recording head and the ink tank are arranged, such as a structure in which the ink tanks are separated from each other and are connected to each other by an ink supply path,
The same effect can be obtained.

Further, the present invention can be applied to, for example, a recording head using an electromechanical transducer such as a piezo element, but among them, a recording head of a type that ejects ink by utilizing thermal energy. It provides an excellent effect in an ink jet recording apparatus using. This is because such a system can achieve high density recording and high definition recording.

[0042]

As is apparent from the above description, according to the present invention (Claim 1), an ink jet recording is performed by ejecting ink from a recording means having a black ink ejection port and a color ink ejection port to a recording medium. In the recording apparatus, the black ink ejection port and the color ink ejection port are covered with a single cap, the inside of the cap is communicated with the atmosphere, and a negative pressure from a negative pressure generation source is applied to the inside of the cap. An empty suction unit for sucking and removing the residual ink is provided, and the suction port for applying a negative pressure from the negative pressure generation source in the cap is closer to the black ink ejection port than the color ink ejection port of the recording unit facing at the time of capping. Is formed in the position of
The communication port for communicating with the atmosphere in the cap is arranged in a region of the color ink ejection port of the recording head facing at the time of capping and at a position farthest from the black ink ejection port or in the vicinity thereof. Therefore, with respect to the recording head having the black ink ejection port and the color ink ejection port, the negative pressure is applied to the inside of the cap communicated with the atmosphere by the single cap and the single suction means to perform the empty ejection. (EN) Provided is an ink jet recording apparatus which can prevent ink mixed with black ink from adhering to the periphery of an outlet and can prevent deterioration in quality of a recorded image due to ink color mixing when recording after idle suction.

According to the second to fourth aspects of the invention, in addition to the structure of the first aspect, a black ink ejection port array consisting of a plurality of black ink ejection ports and a plurality of colors are provided on the ejection port surface of the recording means. A configuration in which color ink ejection port arrays including ink ejection ports are arranged in parallel with each other and are divided and arranged into a black ink ejection port array group and a color ink ejection port array group, on the ejection port surface of the recording unit. A configuration in which a black ink ejection port array group composed of a plurality of black ink ejection ports and a color ink ejection port array group composed of a plurality of color ink ejection ports are arranged in a vertical row, or the suction ports face each other during capping. Since it is arranged in the region of the black ink ejection port array group on the ejection port surface of the recording head and at the position farthest from the color ink ejection port array group or in the vicinity thereof, Mosquito -For a recording head with ink ejection ports, a single cap and a single suction means apply a negative pressure to the inside of the cap that communicates with the atmosphere to perform idle suction, and more efficiently (EN) Provided is an inkjet recording apparatus capable of preventing adhesion of mixed ink with black ink and preventing deterioration of quality of a recorded image due to ink color mixing when recording after idle suction.

According to the invention of claim 5, in addition to the constitution of each of the above claims, the communication port is formed in the bottom portion of the cap integrally as a part of the cap and is a substantially straight through hole in the vertical direction. Since the lower end of the communication port is configured to be opened and closed by the open / close valve, in addition to the above effects, the ink remaining in the cap after idle suction can be easily flowed out from the communication port to the outside. It is possible to eliminate the inconveniences such as residual ink coagulating in the cap or the communication port, resulting in poor vacuum suction, and clogging of the communication port due to coagulated ink.In addition, extra parts such as connecting tubes are required. Therefore, the inkjet recording apparatus is provided which can reduce the cost and improve the assembling property.

According to another aspect of the present invention (claim 8), in a recovery system unit of an ink jet recording apparatus for recording by ejecting ink from a recording means having a black ink ejection port and a color ink ejection port to a recording medium, The black ink ejection port and the color ink ejection port are covered with a single cap, the inside of the cap is communicated with the atmosphere, and a negative pressure from a negative pressure source is applied to the cap to suck the residual ink in the cap. A suction port for removing the negative pressure from the negative pressure source is formed in the cap at a position closer to the black ink discharge port than the color ink discharge port of the recording means facing at the time of capping. The communication port for communicating the inside of the cap with the atmosphere is in the area of the color ink ejection port of the recording head facing at the time of capping, and the black ink is ejected. Since it is arranged at the position farthest from or in the vicinity thereof, a recording head having a black ink ejection port and a color ink ejection port is provided with a single cap and a single suction means inside the cap that is in communication with the atmosphere. It is possible to prevent the mixed ink with black ink from adhering to the periphery of the color discharge port when performing negative suction by applying negative pressure to the ink, and prevent deterioration of the quality of the recorded image due to ink color mixing when recording after empty suction. A recovery system unit of an ink jet recording apparatus is provided.

According to the ninth aspect of the present invention, in addition to the structure of the eighth aspect, the communication port is integrally formed at the bottom of the cap as a part of the cap and is a substantially straight through hole in the vertical direction. Since the lower end of the communication port is configured to be opened and closed by the open / close valve, in addition to the above effects, the ink remaining in the cap after idle suction can be easily flowed out from the communication port to the outside. It is possible to eliminate the inconveniences such as residual ink coagulating in the cap or the communication port, resulting in poor vacuum suction, and clogging of the communication port due to coagulated ink.In addition, extra parts such as connecting tubes are required. Therefore, the recovery system unit of the ink jet recording apparatus is provided which can reduce the cost and improve the assembling property.

[Brief description of drawings]

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

FIG. 2 is a schematic bottom view of the recording unit for showing the arrangement state of a plurality of ejection port arrays on the ejection port surface of the recording unit in FIG.

3 is a schematic vertical sectional view showing a schematic configuration of a recovery system unit in FIG.

FIG. 4 is a schematic plan view of a cap of a recovery system unit of an inkjet recording apparatus to which the present invention has been applied.

5 is a schematic vertical sectional view of a portion including a suction port and a communication port of the cap and the cap holder of FIG.

FIG. 6 is a schematic plan view of another embodiment of the cap of the recovery system unit of the inkjet recording apparatus to which the present invention is applied.

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

[Explanation of symbols]

1 carriage 2 Guide shaft 3 chassis 4 guide rails 5 Transport rollers (paper feed rollers) 6 Platen 7 Recording means (recording head) 8 Carriage motor 9 Timing belt 10 Recording medium (recording paper) 11 pinch rollers 12 Paper ejection roller 13 Recovery unit 14 Automatic paper feeding unit 15 caps 16 Cap holder 17 tubes 18 roller holder 19 Pressure roller 20 pump base 21 Suction port 22 Communication port 23 Open / close valve 24 valve spring 40 Black ink ejection port group 41 Black ink ejection port array 45 suction pump 50 color ink ejection port group 51 Yellow ink ejection port array 52 Magenta ink ejection port array 53 Cyan ink ejection port array 81 Discharge port surface 82 Discharge port 83 Common liquid chamber 84 liquid path 85 Electrothermal converter

Claims (9)

[Claims] 1. In an ink jet recording apparatus for recording by ejecting ink from a recording means having a black ink ejection port and a color ink ejection port to a recording medium, the black ink ejection port and the color ink ejection port are provided with a single cap. A negative suction means for covering and communicating the inside of the cap with the atmosphere and applying a negative pressure from a negative pressure generation source to the inside of the cap to suck and remove the residual ink in the cap. The suction port for applying a negative pressure from the source is formed at a position closer to the black ink ejection port than the color ink ejection port of the recording unit facing at the time of capping, and the communication port for communicating with the atmosphere in the cap is , Located in the area of the color ink ejection port of the recording head facing at the time of capping and at the position farthest from the black ink ejection port or in the vicinity thereof. An inkjet recording device characterized by the above. 2. A black ink ejection port array composed of a plurality of black ink ejection ports and a color ink ejection port array composed of a plurality of color ink ejection ports are arranged in parallel with each other on the ejection port surface of the recording means, and black. The ink jet recording apparatus according to claim 1, wherein the inkjet recording apparatus is divided into an ink ejection port array group and a color ink ejection port array group. 3. A black ink ejection port array group composed of a plurality of black ink ejection ports and a color ink ejection port array group composed of a plurality of color ink ejection ports are arranged vertically in a line on the ejection port surface of the recording means. The inkjet recording apparatus according to claim 1, wherein the inkjet recording apparatus is provided. 4. The suction port is located in a region of the black ink ejection port array group on the ejection port surface of the recording head facing at the time of capping and at a position farthest from the color ink ejection port array group or in the vicinity thereof. The inkjet recording apparatus according to claim 3, wherein the inkjet recording apparatus is provided. 5. The communication port comprises a vertical straight through hole integrally formed at a bottom portion of the cap as a part of the cap, and a lower end of the communication port is opened and closed by an opening / closing valve. The inkjet recording apparatus according to any one of claims 1 to 4. 6. The ink jet recording apparatus according to claim 1, wherein the recording unit includes an electrothermal converter that generates thermal energy used to eject ink. . 7. The ink jet recording apparatus according to claim 6, wherein the recording unit ejects the ink from the ejection port by utilizing film boiling generated in the ink by the thermal energy generated by the electrothermal converter. . 8. In a recovery system unit of an ink jet recording apparatus for recording by ejecting ink from a recording means having a black ink ejection port and a color ink ejection port to a recording medium, the black ink ejection port and the color ink ejection port are separately provided. An empty suction means for covering the inside of the cap with the atmosphere and for applying a negative pressure from a negative pressure generation source to the inside of the cap to suck and remove the residual ink in the cap; The suction port for applying a negative pressure from the negative pressure generation source is formed at a position closer to the black ink ejection port than the color ink ejection port of the recording unit facing at the time of capping, and communicates with the atmosphere in the cap. The communication port is located at a position farthest from the black ink ejection port or in the area of the color ink ejection port of the recording head facing at the time of capping. A recovery system unit that is arranged in the vicinity of the. 9. The communication port comprises a vertical straight through hole integrally formed at a bottom portion of the cap as a part of the cap, and a lower end of the communication port is opened and closed by an opening / closing valve. The recovery system unit of the inkjet recording apparatus according to claim 8.