JP3353782B2 - Liquid injection device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid ejecting apparatus having a head member for ejecting a liquid droplet from a nozzle opening, and more particularly to a liquid ejecting apparatus for preventing a liquid from being thickened at a nozzle opening.

[0002]

2. Description of the Related Art In an ink jet recording apparatus (a kind of liquid ejecting apparatus) such as an ink jet printer or a plotter, a recording head (a head member) is moved along a main scanning direction and recording paper (a kind of a print recording medium). Is moved along the sub-scanning direction, and ink droplets are ejected from nozzle openings of the recording head in conjunction with this movement, thereby recording an image (character) on recording paper. The ejection of the ink droplet (liquid droplet) is performed, for example, by changing the ink pressure in a pressure generating chamber communicating with the nozzle opening.

[0003] Changes in ink pressure are performed using a pressure generating element, for example, a piezoelectric vibrator. In this case, the piezoelectric vibrator is deformed in response to the supplied drive pulse, thereby changing the volume of the pressure chamber. This volume change causes pressure fluctuation in the ink in the pressure chamber, and ink droplets are ejected from the nozzle openings. I do.

[0004] By the way, since the ink is exposed to the air at the nozzle openings of the recording head, the ink solvent (eg, water) evaporates gradually. Due to the evaporation of the ink solvent, the viscosity of the ink at the nozzle opening increases, deteriorating the image quality of the recorded image. That is, when the ink viscosity of the portion increases, the ejected ink droplets may fly in a direction deviated from the normal direction.

Therefore, in the ink jet recording apparatus, measures are taken to prevent the viscosity of the ink at the nozzle opening from increasing. As a measure for increasing the viscosity, there are a flushing operation in which the thickened ink is forcibly ejected outside the recording area, and an agitation operation of the ink due to a minute vibration of the meniscus. Here, the meniscus is a free surface of the ink exposed at the nozzle opening.

Various settings are made for the amount of execution of these maintenance operations in order to guarantee the recording quality of the recording area farthest from the standby position of the recording head. .

[0007]

By the way, in a recording apparatus for recording on a large-sized recording paper such as B0 size, the moving distance of the recording head in the main scanning direction is very long. For this reason,
When performing the flushing operation as a maintenance operation,
A large amount of ink is ejected in the flushing operation so that even if the first ink droplet is ejected in the recording area furthest from the standby position of the recording head, the ink droplet is normally ejected. Similarly, when performing a fine vibration operation (a meniscus stirring operation) as a maintenance operation, the number of times of operation of the pressure generating element is set to be large.

Therefore, in such a printing apparatus that performs the flushing operation, there is a problem that the amount of ink that can be used for printing is relatively small because the amount of ink discharged in the flushing operation is large. Further, the waste liquid absorbing material for collecting the ink discharged by the flushing operation also needs to have a large capacity.

On the other hand, in such a recording apparatus that performs a micro-vibration operation, there is a problem that the life of the recording head is short because the pressure generating element is operated many times.

The present invention has been made in view of such circumstances, and an ink jet recording apparatus capable of more efficiently performing a thickening preventing operation for maintaining good ejection characteristics of ink droplets. In general, it is an object to provide a liquid ejecting apparatus.

[0011]

According to the present invention, there is provided a head member having a nozzle opening and receiving ejection data corresponding to one movement in the main scanning direction, and a head member receiving the ejection data after the head member receives the ejection data. A head scanning mechanism that moves the head member in the main scanning direction, a recovery unit that recovers the viscosity of the liquid at the nozzle opening, and at least a part of an elapsed time from a previous operation end of the recovery unit. A liquid ejecting apparatus, comprising: a measurement timer that performs the measurement; and a control unit that controls the recovery unit based on a time measured by the measurement timer.

According to the present invention, since the recovery means is controlled based on at least a part of the elapsed time from the end of the previous operation of the recovery means, it is extremely efficient according to the state of the liquid in the nozzle opening. A lean recovery operation of the liquid without waste can be performed.

Here, at least a part of the elapsed time from the end of the previous operation of the recovery means is, for example, a time from the end of the previous operation of the recovery means to the end of the reception of the injection data. In this case, it is preferable to perform the next recovery operation (operate the recovery means) immediately after the end of the reception of the injection data.

Alternatively, if the head scanning mechanism moves the head member from the standby position in the main scanning direction after the head member receives the ejection data, and returns the head member to the standby position again, Is the time from the time when it moves in the main scanning direction and returns to the standby position to the time when the reception of the injection data is completed. This is an aspect in consideration of the fact that, out of the elapsed time from the end of the previous operation of the recovery unit, the reception time of the injection data can greatly differ depending on the recording data.

Preferably, the control means further controls the recovery means in consideration of the injection data itself.

More specifically, in the case where the head scanning mechanism does not move the head member in an area after the last liquid droplet is ejected in one movement in the main scanning direction (running beam). Is changed), the control unit determines, based on the ejection data corresponding to the next movement in the main scanning direction,
It is preferable that the recovery means is controlled in accordance with the moving distance of the head member in the next main scanning direction.
Alternatively, in this case, it is preferable that the control means controls the recovery means in accordance with the previous movement distance of the head member in the main scanning direction.

Alternatively, based on the ejection data corresponding to the next movement in the main scanning direction, the control means may determine the distance until the liquid droplet is first ejected during the movement of the head member in the next main scanning direction. Preferably, the recovery means is controlled.

Alternatively, when the head member has a plurality of nozzle openings, and the recovery means recovers the viscosity of the liquid in the nozzle opening portion for each nozzle opening, the control means includes: Based on the ejection data corresponding to the movement in the scanning direction, for each nozzle opening, according to the distance until a liquid droplet is first ejected from the nozzle opening during the next movement of the head member in the main scanning direction, It is preferable to control the recovery means.

Alternatively, it is preferable that the control means controls the recovery means in accordance with a liquid discharge (ejection) ratio during the previous movement of the head member in the main scanning direction.

Alternatively, when the head member has a plurality of nozzle openings, and the recovery means recovers the viscosity of the liquid in the nozzle opening portion for each nozzle opening, the control means controls each nozzle opening. It is preferable that the recovery unit is controlled in accordance with the liquid ejection ratio during the previous movement of the head member in the main scanning direction each time.

Alternatively, the control means controls the recovery means in accordance with the liquid ejection ratio during the movement of the head member in the next main scanning direction, based on the ejection data corresponding to the next movement in the main scanning direction. It is preferred that

Alternatively, if the head member has a plurality of nozzle openings, and the recovery means recovers the viscosity of the liquid in the nozzle opening portion for each nozzle opening, the control means includes the following main means: The recovery means is controlled for each nozzle opening in accordance with the liquid ejection ratio during the next movement of the head member in the main scanning direction based on ejection data corresponding to the movement in the scanning direction. Is preferred.

In the case where the head member has a plurality of nozzle openings each using a different liquid, and the recovery means recovers the viscosity of the liquid at the nozzle opening portion for each nozzle opening, Preferably, the means controls the recovery means for each nozzle opening based on the characteristics of the liquid used at the nozzle opening.

In the case where a sensor for detecting the state of the use environment is provided, it is preferable that the control means controls the recovery means based on the output of the sensor.

Further, in the case where a cap member is provided which is relatively movable between a position separated from the head member and a position in contact with the head member and which seals the nozzle opening when the head member is in contact with the head member. Preferably, the control means causes the cap member to contact the head member based on the time measured by the measurement timer.

The recovery means may be a fine vibration means for finely vibrating the liquid at the nozzle opening. Alternatively, the recovery unit may be a flushing unit that discharges the liquid from the head member outside the ejection area.

Each of the above control means (control device) can be realized by a computer system.

Note that a computer-readable recording medium in which a program for causing a computer system to realize each control unit (control device) is also covered by the present invention.

Here, the recording medium includes not only a floppy disk (registered trademark) or the like which can be recognized as a single unit, but also a network for transmitting various signals.

[0030]

Embodiments of the present invention will be described below with reference to the drawings.

As shown in FIG. 1, the ink jet recording apparatus of the present embodiment is an ink jet printer 1 having a carriage 5 having a cartridge holder 3 capable of holding an ink cartridge 2 and a recording head 4. ing. The carriage 5 is moved by a head scanning mechanism.
It is designed to reciprocate along the main scanning direction.

The head scanning mechanism includes a guide member 6 extending in the left-right direction of the housing, a pulse motor 7 provided on one side of the housing, and a drive pulley connected to the rotation shaft of the pulse motor 7 and driven to rotate. 8, a idler pulley 9 attached to the other side of the housing, a timing belt 10 which is stretched between the drive pulley 8 and the idler pulley 9 and coupled to the carriage 5, and controls the rotation of the pulse motor 7. Control unit 11 (see FIG. 5)
And is composed of Thereby, the pulse motor 7
, The carriage 5, that is, the recording head 4, can be reciprocated in the main scanning direction, which is the width direction of the recording paper 12.

The printer 1 has a paper feeding mechanism for feeding a recording medium such as the recording paper 12 in a paper feeding direction (sub-scanning direction). The paper feed mechanism includes a paper feed motor 13, a paper feed roller 14, and the like. The recording medium such as the recording paper 12 is sequentially sent out in conjunction with the recording operation.

The head scanning mechanism and the paper feeding mechanism of the present embodiment are configured to be able to cope with a large-size recording paper 12 of about B0 size. Further, the printer 1 of the present embodiment
A recording operation is performed when the recording head 4 moves forward (unidirectional recording is performed).

A home position and a standby position of the recording head 4 (carriage 5) are set in an end area within the moving range of the carriage 5 and outside the recording area. As shown in FIG. 2A, the home position is set at one end (right side in the drawing) of the head movement range in which the recording head 4 can move. The standby position is set substantially adjacent to the home position on the recording area side.

In the present invention, a recording operation is performed both when the recording head 4 moves forward and backward (except for a mode such as a third embodiment described later) (performs bidirectional recording). The present invention is also applicable to a printer configured as described above. In such a printer, as shown in FIG. 2B, in addition to the first standby position WP1 substantially adjacent to the home position, a second standby position WP2 is provided at an end opposite to the home position. Can be provided.

The home position is a place where the recording head 4 moves and stays when the power is turned off or when recording is not performed for a long time. When the recording head 4 is at the home position, the cap member 15 of the capping mechanism is moved to the nozzle plate 16 as shown in FIG.
(See FIG. 4) to seal the nozzle opening 17 (see FIG. 4). The cap member 15 is a member formed by molding an elastic member such as rubber into a substantially rectangular tray shape having an open upper surface.
A humectant such as felt is attached inside. When the recording head 4 is sealed by the cap member 15, the inside of the cap is kept at a high humidity, and the nozzle opening 17 is closed.
The evaporation of the ink solvent from the ink is prevented.

The standby position is a position serving as a starting point when the print head 4 is scanned. That is, the recording head 4
Normally, the printer stands by at the standby position, scans from the standby position to the recording area side during the recording operation, and returns to the standby position when the recording operation is completed.

In the case of a printer that performs bidirectional printing, FIG.
With reference to (b), the recording head 4 scans from the state of waiting at the first standby position WP1 toward the second standby position WP2 to perform a printing operation during forward movement. When this recording operation is completed, the apparatus stands by at the second standby position WP2. Next, the recording head 4 scans from the state of waiting at the second standby position WP2 toward the first standby position WP1, and performs a printing operation at the time of returning. When this recording operation is completed, the apparatus stands by at the first standby position WP1. Thereafter, the recording operation at the time of forward movement and the recording operation at the time of backward movement are alternately and repeatedly executed.

At the standby position, there is provided an ink receiving member for collecting ink discharged from the recording head 4 by a flushing operation (a type of maintenance operation). In the present embodiment, the cap member 15 is
Also serves as an ink receiving member. That is, the cap member 15
As shown in FIG. 3A, the recording head 4 is normally disposed at a position below the standby position of the recording head 4 (a position slightly separated below the nozzle plate 16). Then, as the recording head 4 moves to the home position, FIG.
As shown in (d), the nozzle opening 17 is moved obliquely upward (to the home position side and the nozzle plate 16 side),
Is sealed.

In the case of a printer that performs bidirectional printing, as shown in FIG. 2B, an ink receiving member 18 is also provided at the second standby position WP2. The ink receiving member 18 may be constituted by, for example, a box-shaped flushing box whose surface facing the recording head 4 is open.

Further, in this embodiment, an acceleration area is set between the standby position and the recording area. The acceleration area is an area for accelerating the scanning speed of the recording head 4 to a predetermined speed.

Next, the recording head 4 will be described. As shown in FIG. 4, the recording head 4 has an ink chamber 20 to which ink from the ink cartridge 2 (see FIG. 1) is supplied.
A nozzle plate 16 in which a plurality of (for example, 64) nozzle openings 17 are arranged in the sub-scanning direction;
And a plurality of pressure chambers 22 provided corresponding to each of the pressure chambers. The pressure chamber 22 expands and contracts due to deformation of the piezoelectric vibrator 21.

The ink chamber 20 and the pressure chamber 22 communicate with each other through an ink supply port 23 and a supply-side communication hole 24. Further, the pressure chamber 22 and the nozzle opening 17 are communicated via the first nozzle communication hole 25 and the second nozzle communication hole 26. That is, a series of ink flow paths from the ink chamber 20 to the nozzle openings 17 through the pressure chambers 22 are formed for each nozzle opening 17.

The above-described piezoelectric vibrator 21 is a so-called flexural vibration mode piezoelectric vibrator 21. When the piezoelectric vibrator 21 in the flexural vibration mode is used, the piezoelectric vibrator 21 contracts in a direction orthogonal to the electric field due to charging, the pressure chamber 22 contracts, and the charged piezoelectric vibrator 21 is discharged. 21 extends in a direction orthogonal to the electric field, and the pressure chamber 22 expands.

That is, in the recording head 4, as the piezoelectric vibrator 21 is charged and discharged, the capacity of the corresponding pressure chamber 22 changes. By utilizing such pressure fluctuations of the pressure chamber 22, it is possible to eject ink droplets from the nozzle openings 17 or to vibrate the meniscus (the free surface of the ink exposed at the nozzle openings 17) finely.

For example, when ejecting ink droplets,
The pressure chamber 22 having the reference volume is once expanded and then rapidly contracted. By doing so, the ink pressure in the pressure chamber 22 sharply rises with the rapid contraction of the pressure chamber 22, and ink droplets are ejected from the nozzle openings 17. Also,
When performing a micro-vibration operation (a type of maintenance operation) that vibrates the meniscus and stirs the ink near the nozzle opening 17 to prevent the ink from thickening, the pressure chamber 22 is set to such an extent that ink droplets are not ejected. Inflate and shrink. It should be noted that a so-called longitudinal vibration mode piezoelectric vibrator can be used instead of the above-described flexural vibration mode piezoelectric vibrator 21. A piezoelectric vibrator in the longitudinal vibration mode is a piezoelectric vibrator that expands a pressure chamber by deformation due to charging and contracts the pressure chamber by deformation due to discharging.

The recording head 4 is preferably a multicolor recording head capable of recording a plurality of different colors. The multicolor recording head includes a plurality of head units, and the type of ink to be used is set for each head unit.

For example, in a recording head having four head units, a black head unit capable of discharging black ink, a cyan head unit capable of discharging cyan ink, and a magenta head unit capable of discharging magenta ink are provided. And a yellow head unit capable of discharging yellow ink.

Next, the electrical configuration of the printer 1 will be described. As shown in FIG. 5, the inkjet printer 1 includes a printer controller 30 and a print engine 31.

The printer controller 30 includes an external interface (external I / F) 32, a RAM 33 for temporarily storing various data, a ROM 34 for storing a control program and the like, and a control unit 11 including a CPU and the like.
An oscillation circuit 35 for generating a clock signal; a drive signal generation circuit 36 for generating a drive signal COM to be supplied to the recording head 4; and dot pattern data (bits) developed based on a drive signal and print data. An internal interface (internal I / F) 37 for transmitting map data) and the like to the print engine 31 and a measurement timer 38 are provided.

The external I / F 32 receives print data composed of, for example, character codes, graphic functions, image data, and the like from a host computer (not shown). In addition, a busy signal (BUSY) and an acknowledgment signal (ACK) are transmitted through the external I / F 32.
Output to the host computer and the like.

The RAM 33 has a reception buffer, an intermediate buffer, an output buffer, a work memory, and (not shown). The receiving buffer temporarily stores the print data received via the external I / F 32, the intermediate buffer stores the intermediate code data converted by the control unit 11, and the output buffer stores the dot pattern data. Is stored. Here, dot pattern data refers to decoding (translation) of intermediate code data (for example, gradation data).
This is the print data obtained by performing

The ROM 34 stores font data, graphic functions, and the like, in addition to a control program (control routine) for performing various data processing. Further, the ROM 34 serves as a maintenance information holding unit.
The setting data for the maintenance operation is also stored.

The control unit 11 performs various controls according to a control program stored in the ROM 34. For example, the print data in the reception buffer is read, and the print data is converted into intermediate code data, and the intermediate code data is stored in the intermediate buffer. The control unit 11
Analyzes the intermediate code data read from the intermediate buffer and develops (decodes) it into dot pattern data by referring to the font data and graphic functions stored in the ROM 34. Then, after performing necessary decoration processing, the control unit 11 stores the dot pattern data in the output buffer.

If one recordable dot pattern data is obtained by one main scan of the recording head 4,
The one line of dot pattern data is sequentially output from the output buffer to the electric drive system 39 of the recording head 4 through the internal I / F 37, and the carriage 5 is scanned to print one line. When one line of dot pattern data is output from the output buffer, the expanded intermediate code data is erased from the intermediate buffer, and expansion processing for the next intermediate code data is performed.

Further, the control section 11 controls a maintenance operation (recovery operation) performed prior to the recording operation by the recording head 4.

The measurement timer 38 measures the elapsed time (one pass time) from the end of the previous maintenance operation to the end of the reception of print data of the next printing operation after one pass of printing operation. It has become.

The print engine 31 includes a paper feed motor 13 as a paper feed mechanism, a pulse motor 7 as a head scanning mechanism, and an electric drive system 9 for the recording head 4.

Next, the electric drive system 39 of the recording head 4 will be described. The electric drive system 39 is, as shown in FIG.
Shift register circuit 40, latch circuit 41, level shifter circuit 42, switch circuit 43 electrically connected in order
And a piezoelectric vibrator 21. These shift register circuit 40, latch circuit 41, level shifter circuit 4
2. The switch circuit 43 and the piezoelectric vibrator 21 are provided for each nozzle opening 17 of the recording head 4, respectively.

In the electric drive system 39, the switch circuit 4
If the print data added to the switch 3 is “1”, the switch circuit 4
Reference numeral 3 denotes a connection state, in which a drive signal (COM) is directly applied to the piezoelectric vibrators 21, and each piezoelectric vibrator 21 is deformed according to the signal waveform of the drive signal. On the other hand, when the print data applied to the switch circuit 43 is “0”, the switch circuit 43 is disconnected, and the supply of the drive signal to the piezoelectric vibrator 21 is cut off.

As described above, the drive signal can be selectively supplied to each of the piezoelectric vibrators 21 based on the print data.
For this reason, the nozzle opening 1
7, ink droplets can be ejected, or the meniscus can be slightly vibrated.

Next, the operation of the printer 1 will be described with reference to FIGS.

When the power is turned on, first, a necessary initialization operation is performed. Thereafter, the recording head 4 waits at the standby position (the state of FIG. 3A). When one line of print data is output from the output buffer of the RAM 33, the recording head 4 performs a maintenance operation (recovery operation) prior to the recording operation.

This maintenance operation is performed in order to maintain the ability of the recording head 4 to eject ink droplets.
For example, there are a flushing operation and a micro-vibration operation, which are appropriately selected and performed.

Specifically, the flushing operation is an operation for forcibly discharging ink from the recording head 4 toward the ink receiving member (cap member 15) outside the recording area. The flushing operation is performed while stopping at the standby position. When the flushing operation is performed, the thickened ink in the vicinity of the nozzle opening 17 is discharged out of the recording head 4, and is replaced with ink in a good state.

As described above, the micro-vibration operation is an operation in which the meniscus is micro-vibrated by changing the pressure of the pressure chamber 22 to such an extent that ink droplets are not ejected.
This is performed while the recording head 4 is stopped at the standby position and while moving in the acceleration area.

The initial value of the execution amount of the maintenance operation in the first pass of the main scan (first printing operation) is the outermost portion X (FIG. 2) of the printing area furthest from the standby position.
(See (a)), the value is such that the ink ejection characteristics can be maintained satisfactorily, that is, the image quality printed at the extreme end can be guaranteed.

For example, when a flushing operation is performed as a maintenance operation, the initial value of the number of ejections of ink droplets (the number of flushing shots) in the flushing operation is set to 200 times. Similarly, when performing the fine vibration operation as the maintenance operation, the initial value of the number of times of operation (the number of fine vibrations) of the piezoelectric vibrator 21 in the fine vibration operation is set to 200.
Set to times.

The movement of the recording head 4 is started immediately after the flushing operation when the flushing operation is performed, and at an appropriate timing after the end of the reception of the print data when the micro-vibration operation is performed. Be started.

After the maintenance operation is performed, a recording operation based on the print data is performed in the recording area.

When the printing operation of the first pass (first time) is completed (see FIGS. 3A and 3B), the print head 4 returns to the standby position and waits (FIGS. 3C and 3C). 3
(A)). The print head 4 that has returned to the standby position after completing the printing operation of the first pass stands by at the standby position until the reception of the print data of the next row (pass) is completed. Then, after receiving the next one line of print data transmitted from the printer controller 30, the second pass (second time) maintenance operation is performed.

The execution amount of the maintenance operation in the second pass is set according to the one pass time of the recording head 4 measured by the measurement timer 38.

That is, the control unit 11 sets the measurement timer 38
, From the end of the maintenance operation performed for the first time, through the recording operation of the first pass by the recording head 4 and the return to the standby position, the reception of print data of the recording operation of the second pass. The number of flushing shots in the flushing operation and the number of fine vibrations in the fine vibration operation are set based on the elapsed time until the end point.

This setting is made based on the maintenance setting data stored in the ROM 34. This maintenance setting data is given as table information as shown in the graph of FIG. 6, for example.

The maintenance setting data shown in the graph of FIG. 6 indicates that the maintenance execution amount (the number of flushing shots or the number of fine vibrations) corresponding to one pass time of 0 to 5 seconds is 1
00, and the maintenance execution amount corresponding to one pass time of 25 seconds is 200 times. In this case, one pass time when the print head 4 that has returned to the standby position after completing one print operation immediately starts moving for the next print operation is 5 seconds. . That is, the fluctuation of the one-pass time mainly depends on the amount of print data to be received. However, if the scanning of the recording head 4 is not performed over the entirety of one line in accordance with the print data, for example, if the recording head 4 is not scanned in the area after the final ink droplet ejection, the Also fluctuates one pass time.

The maintenance execution amount in a range where the one-pass time is more than 5 seconds and less than 25 seconds is increased with an increase in the one-pass time so that a proportional relationship with the one-pass time is established. I have.

Then, the control section 11 sets the maintenance execution amount based on the one-pass time, and causes the maintenance operation to be performed based on the set execution amount.

For example, when the above-mentioned one pass time is 15 seconds in the printer 1 performing the flushing operation, 150 flushing shots are set, and the ink droplet is ejected 150 times by the flushing operation. In addition, when the first pass time is 5 seconds, that is, when the print head 4 that has completed the first pass printing operation and returned to the standby position immediately starts moving for the second pass printing operation, 100 is set as the number of flushing shots, and 100 ink droplets are ejected by the flushing operation. That is, in this flushing operation, the amount of ink to be discharged is increased or decreased in accordance with one pass time of the recording head 4.

Similarly, the printer 1 that performs the fine vibration operation
If the pass time is 15 seconds, the number of fine vibrations is set to 150
And the number of micro-vibrations is set to 100 if the one-pass time is 5 seconds. That is, in the fine vibration operation, the number of times of fine vibration is increased or decreased according to one pass time of the print head 4.

As described above, when the execution amount of the maintenance operation is set in accordance with the one-pass time of the print head 4, an excessive maintenance operation is executed while guaranteeing the image quality at the end of the printing area. Can be avoided, and the maintenance operation can be performed efficiently.

That is, when the one-pass time of the recording head 4 is relatively short, the period during which the meniscus is exposed to the outside air is short, and there may be residual vibration of the meniscus in the previous recording operation. For this reason, the viscosity of the ink near the nozzle opening 17 hardly increases. Therefore, even if the execution amount of the maintenance operation is set relatively small, it is possible to guarantee the image quality at the end of the recording area.

On the other hand, when the one-pass time of the recording head 4 is relatively long, the period during which the meniscus is exposed to the outside air is long.
Viscosity of nearby ink tends to increase until it affects printing. Therefore, in order to guarantee the image quality at the end of the recording area, the execution amount of the maintenance operation is set to be large.

If one pass time of the recording head 4 exceeds a predetermined capping time (for example, 25 seconds), that is, if the reception of print data is not completed even after the elapse of the capping time, the control unit Numeral 11 indicates capping. According to the capping instruction, the recording head 4 moves from the standby position to the home position,
The cap member 15 contacts the nozzle plate 16 to seal the nozzle opening 17 (the state shown in FIG. 3D). In such a capping state, the humidity inside the cap is increased by the humectant impregnated with the ink, so that the evaporation of the ink solvent from the nozzle opening 17 is prevented. This can prevent the ink density in the recording head 4 from excessively increasing.

Such a capping state is, for example, as follows:
It is canceled when the reception of the print data (dot pattern data) is completed. When the capping state is released, the recording head 4 moves to the standby position. The initial value for the first pass is used for the execution amount of the maintenance operation thereafter.

In the present embodiment, the operations after the third pass (the third time) are repeatedly executed in the same manner as the printing operation in the second pass.

As described above, according to the present embodiment, in the printer 1 which performs the flushing operation as the maintenance operation, the amount of ink discharged by the flushing operation is the minimum required according to one pass time of the recording head 4. In the amount. For this reason, the amount of ink that can be used for recording can be increased, that is, more recording can be performed with a limited amount of ink filled in the ink cartridge 2.

Further, the capacity of the waste liquid collecting material for collecting the ink discharged by the flushing can be reduced.

Further, in the printer 1 which performs a fine vibration operation as a maintenance operation, the piezoelectric vibrator 2 accompanying the fine vibration operation is provided.
1 can be reduced to the minimum required. For this reason, the life of the recording head 4 can be extended.

In the above embodiment, the case where the flushing operation is performed while the recording head 4 is at the standby position has been described. However, the present invention is not limited to this. It may be arranged so that the flushing operation is performed while the recording head 4 is moving in the acceleration region.

Next, a second embodiment of the present invention will be described. The measurement timer 38 of the ink jet recording apparatus according to the present embodiment measures the carriage standby time from when the recording head 4 returns to the standby position to when the reception of the print data is completed.

The control unit 11 of the present embodiment controls the standby time measured by the measurement timer 38, that is, the elapsed time from the return to the standby position after the end of the printing operation to the end of the reception of the print data of the next printing operation. The number of flushing shots in the flushing operation and the number of fine vibrations in the fine vibration operation are set based on the time.

This setting is made based on the maintenance setting data stored in the ROM 34. This maintenance setting data is given as table information as shown in the graph of FIG. 7, for example.

The maintenance setting data shown in the graph of FIG. 7 shows that the maintenance execution amount (the number of flushing shots or the number of minute vibrations) corresponding to the standby time of 0 second is 100 times, and the maintenance execution amount corresponding to the standby time of 20 seconds. 200 times.

Further, the maintenance execution amount in the range where the standby time is more than 0 second and less than 20 seconds is increased with the increase of the standby time so that a proportional relationship with the standby time is established.

The other structure is the same as the first structure shown in FIGS.
The configuration is substantially the same as that of the embodiment. In the second embodiment, the same parts as those in the first embodiment shown in FIGS. 1 to 6 are denoted by the same reference numerals, and detailed description is omitted.

The control unit 11 according to the present embodiment sets the maintenance execution amount based on the standby time, and executes the maintenance operation based on the set execution amount.

For example, when the printer 1 performing the flushing operation has a standby time of 10 seconds, the number of flushing shots is set to 150, and the ink droplet is ejected 150 times by the flushing operation. Also, the waiting time is 0
Seconds, that is, when the recording head 4 returning to the standby position after completing the recording operation of the first pass immediately starts moving for the recording operation of the second pass, the number of flushing shots is set to 100 times. After setting, the ink droplet is ejected 100 times by the flushing operation. That is, in this flushing operation, the amount of ink to be discharged is increased or decreased according to the standby time of the recording head 4.

Similarly, if the standby time is 10 seconds in the printer 1 performing the micro-vibration operation, the number of micro-vibrations is set to 150 times, and if the standby time is 0 seconds, the number of micro-vibrations is set to Set to 100 times. That is, in the fine vibration operation, the number of fine vibrations is increased or decreased according to the standby time of the recording head 4.

As described above, even when the execution amount of the maintenance operation is set according to the standby time of the recording head 4, an excessive maintenance operation is executed while guaranteeing the image quality at the end of the recording area. Thus, the maintenance operation can be performed efficiently.

If the standby time of the recording head 4 exceeds a predetermined capping time (for example, 20 seconds), that is, if the reception of print data has not been completed even after the elapse of the capping time, the control unit 11 Indicates capping. According to the capping instruction, the recording head 4
Moves from the standby position to the home position, and the cap member 15 contacts the nozzle plate 16 to seal the nozzle opening 17 (the state of FIG. 3D). In such a capping state, the humidity inside the cap is increased by the humectant impregnated with the ink, so that the evaporation of the ink solvent from the nozzle opening 17 is prevented. This can prevent the ink density in the recording head 4 from excessively increasing.

Next, a third embodiment of the present invention will be described. FIG. 8 is a diagram showing the relationship between the standby time and the maintenance execution amount (the number of flushing shots or the number of fine vibrations) and the relationship between the standby time and the capping time in the present embodiment. Control unit 11 of the present embodiment
Sets the maintenance execution amount in consideration of the number of print digits in the printing operation, that is, the scanning amount of the printing head 4 in the main scanning direction.

More specifically, in this embodiment, the full digit setting data and 1 /
Either 2-digit setting data or 1 / 3-digit setting data is used. Each of these setting data is table data, and is used as maintenance setting data in the ROM.
34.

The full digit setting data indicates that the scan end position of the recording head 4 in the current recording operation performed after the maintenance operation is substantially at the center (1/2) of the recording area in the main scanning direction.
) Is used when the position is within the range of the outermost end X (last digit) of the recording area farthest from the standby position from the position beyond the digit.

The 1/2 digit setting data indicates that the scan end position of the recording head 4 in the above-described current recording operation is shifted from the position beyond the approximately 1/3 position (1/3 digit) of the recording area in the main scanning direction. This data is used when it is within the range of approximately the center (1/2 digit) in the scanning direction.

The 1 / 3-digit setting data indicates that the scan end position of the recording head 4 in the current recording operation is within a range of approximately 1/3 (1/3 digit) of the recording area in the main scanning direction. This is the data used for

Note that the scan end position of the recording head 4 can be obtained based on, for example, print data developed in the RAM 33.

In each of these setting data, the maintenance execution amount increases as the standby time increases so that a proportional relationship with the standby time is established.

When the full digit setting data, the 1/2 digit setting data, and the 1/3 digit setting data are compared, if the standby time is the same, the value of the maintenance execution amount corresponding to the full digit setting data is the largest. And the maintenance execution amount corresponding to the 1/2 digit setting data is set to a value smaller than the maintenance execution amount of the full digit setting data.
The maintenance execution amount corresponding to the digit setting data is set to a value smaller than the maintenance execution amount of the 1/2 digit setting data.

The other configuration is substantially the same as that of the second embodiment described with reference to FIG. In the third embodiment, the same portions as those in the second embodiment are denoted by the same reference numerals, and detailed description is omitted.

Based on the above setting data, the controller 11 sets the maintenance execution amount with respect to the standby time to a smaller value as the scanning amount of the recording head 4 in the current recording operation is smaller.

That is, the recording head 4 in the current recording operation
When the scanning amount is small (the recording digit is short), the idle running distance of the recording head 4 is short even if the first ink droplet is ejected at the position farthest from the standby position in the scanning range. For this reason, the amount of evaporation of the ink solvent is small, and the ink viscosity near the nozzle opening 17 is unlikely to increase until it affects printing. Therefore, even if the maintenance execution amount is set smaller, the image quality at the end of the scanning range can be guaranteed.

On the other hand, when the scanning amount of the recording head 4 is large (the recording digit is long), if the first ink droplet is ejected at the position farthest from the standby position in the scanning range, the idling distance of the recording head 4 is reduced. Since the length is long, the amount of evaporation of the ink solvent is large, and the viscosity of the ink near the nozzle opening 17 tends to increase until it affects printing. Therefore, in order to guarantee the image quality at the end of the scanning range, the execution amount of the maintenance operation is set to be large.

As for the capping time, the full digit recording data is set to be the shortest, the 1/2 digit setting data is set to the second shortest, and the 1/3 digit setting data is set to the longest.

That is, when the scanning amount of the recording head 4 in the current recording operation is large, if the first ink droplet is ejected at the position farthest from the standby position, the idling distance of the recording head 4 becomes longer. Therefore, there is a high possibility that ink droplets will be ejected in a state where the ink viscosity is excessively increased. Therefore, the capping time is set relatively short in order to guarantee the image quality at the end of the scanning range.

On the other hand, when the scanning amount of the recording head 4 is small, the idling distance of the recording head 4 is short even if the first ink droplet is ejected at the position farthest from the standby position in the scanning range. For this reason, there is little possibility that the ink droplets will be ejected in a state where the ink viscosity is excessively increased. Therefore, even if the capping time is set relatively long, the image quality at the end of the scanning range can be guaranteed.

In the present embodiment, the maintenance execution amount may be set in consideration of the scan amount of the print head 4 in the previous print operation instead of the scan amount of the print head 4 in the current print operation. .

That is, the recording head 4 in the previous recording operation
Is small, the idle running distance and idle running time from when the recording head 4 returns to the standby position from the scanning end position can be shortened. For this reason, the amount of evaporation of the ink solvent during idling is small, and the ink viscosity near the nozzle opening 17 is unlikely to increase until it affects printing. Therefore, even if the maintenance execution amount is set smaller, it is possible to guarantee the image quality of the next recording area (including the end).

On the other hand, when the scanning amount of the recording head 4 is large (the recording digit is long), the above-mentioned idle running distance and idle running time are long.
For this reason, the amount of evaporation of the ink solvent accompanying idling is large, and the ink viscosity near the nozzle opening 17 tends to increase until it affects printing. Therefore, in order to guarantee the image quality of the next recording area (including the end), a large maintenance execution amount is set.

Similarly, the capping time can be set in consideration of the scanning amount of the recording head 4 in the previous recording operation.

That is, when the scanning amount of the recording head 4 is large in the previous recording operation, the nozzle opening 17
An excessive increase in ink viscosity in the vicinity is likely to occur. Therefore,
Set the capping time relatively short and set the nozzle opening 1
The ink viscosity around 7 is prevented from excessively increasing.

On the other hand, if the scanning amount of the recording head 4 was small in the previous recording operation, the nozzle opening 1
There is little possibility that the ink viscosity near 7 is excessively increased. Therefore, even if the capping time is set long, image quality at the end of the next recording area can be guaranteed.

Further, it is also effective to set the maintenance execution amount in consideration of both the scan amount of the print head 4 in the previous print operation and the scan amount of the print head 4 in the current print operation. For example, the average scan amount of the scan amount of the print head 4 in the previous print operation and the scan amount of the print head 4 in the present print operation is used, or the scan amount of the print head 4 in the previous print operation and the current print amount are used. The longer one of the scanning amount of the recording head 4 in the operation can be used.

As described above, in the present embodiment, the maintenance execution amount is set in consideration of the scanning amount of the recording head 4 in the recording operation. Therefore, the degree of evaporation of the ink solvent due to the idling of the recording head 4 and the like are determined. The maintenance operation can be optimized.

As a result, when the flushing operation is performed, wasteful ink consumption can be further suppressed.
When the micro-vibration operation is performed, the life of the piezoelectric vibrator 21 can be further extended.

The division of each setting data is not limited to the above example, but can be arbitrarily set.

Next, a fourth embodiment of the present invention will be described. FIG. 9 is a diagram showing the relationship between the standby time and the maintenance execution amount (the number of flushing shots or the number of fine vibrations) and the relationship between the standby time and the capping time in the present embodiment. Control unit 11 of the present embodiment
Sets the maintenance execution amount in consideration of the scanning amount until the first ink droplet (first dot) in the printing operation is ejected.

In this case, the control unit 11 determines the scanning amount of the recording head 4 until the nozzle opening 17 ejects the first ink droplet in the current recording operation, based on the print data, the number of pulses supplied to the pulse motor 7, and the like. To get. And
The execution amount of the maintenance operation with respect to the standby time (the number of ejections of ink droplets in the flushing operation and the number of operations of the piezoelectric vibrator 21 in the fine vibration operation) is set in consideration of the acquired scanning amount.

In the present embodiment, similar to the third embodiment, based on one line of print data, full digit setting data, 1/2 digit setting data, and 1/3 digit setting data are used. And any of the following data is used. Each of these setting data is table data, and is recorded in the ROM 34 as maintenance setting data.

The full digit setting data is a position where the first ink droplet ejection position of the recording head 4 in the current recording operation performed after the maintenance operation exceeds the approximate center (1/2 digit) of the recording area in the main scanning direction. This data is used when it is within the range of the end X (last digit) of the recording area farthest from the standby position.

The 1/2 digit setting data indicates that the first ink droplet ejection position of the recording head 4 in the above-described current recording operation is
This data is used when the print area is within a range of approximately the center (1/2 digit) in the main scanning direction from a position exceeding approximately 1/3 position (1/3 digit) in the main scanning direction.

The 1 / 3-digit setting data is set so that the first ink droplet ejection position of the recording head 4 in the current recording operation is within a range (approximately 1/3 digit) of approximately 1/3 of the recording area in the main scanning direction. This is the data that will be used if there is.

The first ink droplet ejection position of the recording head 4 can be obtained based on, for example, print data developed in the RAM 33.

In each of these setting data, the maintenance execution amount increases as the standby time increases so that a proportional relationship with the standby time is established.

When the full digit setting data, the 1/2 digit setting data, and the 1/3 digit setting data are compared, if the standby time is the same, the value of the maintenance execution amount corresponding to the full digit setting data is the largest. And the maintenance execution amount corresponding to the 1/2 digit setting data is set to a value smaller than the maintenance execution amount of the full digit setting data.
The maintenance execution amount corresponding to the digit setting data is set to a value smaller than the maintenance execution amount of the 1/2 digit setting data.

The other structure is substantially the same as that of the third embodiment described with reference to FIG. In the fourth embodiment, the same parts as those in the third embodiment are denoted by the same reference numerals, and detailed description is omitted.

On the basis of the above setting data, the control unit 11 performs maintenance for the standby time as the idling distance and the idling time until the recording head 4 ejects the first ink droplet in the current recording operation become shorter. The execution amount is set to a small value.

That is, in the present recording operation, the recording head 4
If the idle travel distance and idle travel time until the first ink droplet is ejected is short, the amount of evaporation of the ink solvent is small, and the ink viscosity near the nozzle opening 17 does not easily increase until it affects printing. Therefore, even if the maintenance execution amount is set smaller, it is possible to guarantee the image quality of the ink droplets ejected first.

On the other hand, when the idling distance and idling time until the recording head 4 ejects the first ink droplet is long, the amount of evaporation of the ink solvent is large and the ink viscosity near the nozzle opening 17 affects the recording. Easy to rise. Therefore, in order to guarantee the image quality by the ink droplets ejected first, the amount of execution of the maintenance operation is set to be large.

Regarding the capping time, the full digit recording data is set to be the shortest, the 1/2 digit setting data is set to the second shortest, and the 1/3 digit setting data is set to the longest.

This is because if the idling distance and idling time of the recording head 4 are long, the first ink droplet is likely to be ejected in a state where the ink viscosity is excessively increased. The purpose is to do.

On the other hand, when the idling distance and idling time of the recording head 4 are short, there is a small possibility that ink droplets are ejected in a state where the ink viscosity is excessively increased. Therefore, the capping time is set to be relatively long. is there.

As described above, in the present embodiment, the maintenance execution amount is set in consideration of the position where the recording head 4 ejects the first ink droplet in the recording operation. The maintenance operation can be further optimized by considering the evaporation of the water more accurately.

As a result, when the flushing operation is performed, wasteful ink consumption can be further suppressed.
When the micro-vibration operation is performed, the life of the piezoelectric vibrator 21 can be further extended.

It should be noted that the division of each set data is not limited to the above example, but can be set arbitrarily.

The "first ink droplet" may be the first ink droplet for the recording head 4 (for all the nozzle openings 17), or may be the first ink droplet for each nozzle opening. In the latter case, the execution amount of the maintenance operation can be set for each nozzle opening 17. In this case, the maintenance operation can be further optimized.

Next, a fifth embodiment of the present invention will be described. FIG. 10 is a diagram showing the relationship between the standby time and the maintenance execution amount (the number of flushing shots or the number of fine vibrations) and the relationship between the standby time and the capping time in the present embodiment. Control unit 11 of the present embodiment
Sets the maintenance execution amount in consideration of the ink discharge ratio (print duty) in the printing operation. Here, the printing duty means the dot recording ratio, that is, the ratio of the number of dots actually recorded to the total number of dots recordable in one main scan.

More specifically, in the present embodiment, 20% setting data and 20%
Either% to 50% setting data or 50% setting data is used. Each of these setting data is table data, and R is set as maintenance setting data.
Recorded in OM34.

The 20% setting data is used when the print duty in the previous printing operation was 20% or less.

The 20% to 50% setting data is used when the print duty in the previous printing operation is more than 20% and less than 50%.

The 50% setting data is used when the print duty in the previous printing operation is 50% or more.

For example, the nozzle openings 1 forming a nozzle row
If 7 is 64 and the number of dots in the main scanning direction is 1000, the total number of dots becomes 64000 (64 × 1000). In this case, if the number of dots actually recorded is 12800, the print duty is 20%. Similarly, if the number of dots actually recorded is 32,000, the printing duty is 50%.

The number of dots actually recorded can be obtained based on, for example, print data (dot pattern data) developed in the RAM 33.

For each of these setting data, the maintenance execution amount increases with an increase in the standby time so that a proportional relationship with the standby time is established.

Then, 20% setting data and 20% to 50%
When comparing the% setting data with the 50% setting data, if the standby time is the same, the maintenance execution amount corresponding to the 20% setting data is set to the largest value, and 20% to 50%.
The maintenance execution amount corresponding to the% setting data is set to a value smaller than the maintenance execution amount of the 20% setting data, and the maintenance execution amount corresponding to the 50% setting data is smaller than the maintenance execution amount of the 20% to 50% setting data. It is set to a smaller value.

The other configuration is substantially the same as that of the second embodiment described with reference to FIG. In the fifth embodiment, the same portions as those in the second embodiment are denoted by the same reference numerals, and detailed description is omitted.

Based on the above setting data, the control section 11 sets the maintenance execution amount with respect to the standby time to a smaller value as the dot recording ratio in the previous recording operation is higher.

The high printing duty in the previous recording operation means that the frequency of ejection of ink droplets from each nozzle opening 17 was high on average. That is, in this case, it is difficult for the ink viscosity near the nozzle opening 17 to increase until it affects printing. Therefore, even if the maintenance execution amount is set smaller, the image quality in the current recording area can be guaranteed.

On the other hand, a low print duty in the previous recording operation means that the frequency of ejection of ink droplets from each nozzle opening 17 was low on average. That is,
In this case, the ink viscosity in the vicinity of the nozzle opening 17 tends to increase until it affects printing. Therefore, in order to guarantee the image quality in the current recording area, the amount of execution of the maintenance operation is set to be large.

Further, regarding the capping time, 20
The% setting data is set to the shortest, the 20% to 50% setting data is set to the second shortest, and the 50% setting data is set to the longest.

That is, when the print duty in the previous printing operation was low, the time required for the ink viscosity in the vicinity of the nozzle opening 17 to rise until it affected printing was relatively short. Therefore, in order to guarantee the image quality at the end of the current recording area,
Set the capping time relatively short.

On the other hand, when the printing duty in the previous printing operation was high, the time required for the ink viscosity in the vicinity of the nozzle opening 17 to rise until it affected printing was relatively long. Therefore, even if the capping time is set relatively long, the image quality at the end of the current recording area can be guaranteed.

In the present embodiment, the maintenance execution amount may be set in consideration of the print duty of the print head 4 in the current print operation, instead of the print duty of the print head 4 in the previous print operation. .

That is, a high print duty in the current recording operation means that the frequency of ejection of ink droplets from each nozzle opening 17 is high on average. That is, in this case, it is difficult for the ink viscosity near the nozzle opening 17 to increase until it affects printing. Therefore, even if the maintenance execution amount is set smaller, the image quality in the current recording area can be guaranteed.

On the other hand, a low print duty in the current printing operation means that the frequency of ejection of ink droplets from each nozzle opening 17 is low on average. That is, in this case, the ink viscosity in the vicinity of the nozzle opening 17 tends to increase until it affects printing. Therefore, in order to guarantee the image quality in the current recording area, a large maintenance execution amount is set.

Similarly, the capping time can be set in consideration of the print duty in the current printing operation.

That is, when the print duty in the current printing operation is low, there is a high possibility that the idle running distance and idle running time until the first ink droplet is ejected in the current printing operation is long. Therefore, the capping time is set relatively short in order to guarantee the image quality of the ink droplets ejected first.

On the other hand, when the print duty in the current printing operation is high, there is a high possibility that the idle running distance and the idle running time until the first ink droplet is ejected in the current printing operation are short. Therefore, even if the capping time is set relatively long, it is possible to guarantee the image quality of the ink droplets ejected first.

Further, it is also effective to set the maintenance execution amount in consideration of both the printing duty in the previous printing operation and the printing duty in the current printing operation. For example, the average of the previous print duty and the current print duty can be used, or the smaller value of the previous print duty and the current print duty can be used.

As described above, in the present embodiment, since the maintenance execution amount is set in consideration of the print duty in the printing operation, the frequency of ink droplet ejection in the printing operation can be considered, and the maintenance operation can be further optimized.

As a result, when the flushing operation is performed, wasteful ink consumption can be further suppressed.
When the micro-vibration operation is performed, the life of the piezoelectric vibrator 21 can be further extended.

The division of each setting data is not limited to the above example, but can be set arbitrarily.

Further, in the present embodiment, the print duty of the entire recording head 4 is considered, but the print duty may be considered for each nozzle opening. In the latter case, the execution amount of the maintenance operation can be set for each nozzle opening 17. In this case, the maintenance operation can be further optimized.

In each of the above embodiments, the control unit 11
Can set the maintenance execution amount in consideration of the type (characteristic) of the ink used for recording. this is,
This takes into account that the degree of viscosity increase due to the evaporation of the ink solvent differs for each type of ink.

For example, in the case of a dark color ink such as black, the viscosity of the ink tends to increase due to the evaporation of the ink solvent. Conversely, in the case of light-colored (light-colored) inks such as yellow, light magenta, and light cyan, an increase in ink viscosity due to evaporation of the ink soot hardly occurs. In the case of pigment-based inks,
The ink viscosity tends to increase due to the evaporation of the ink solvent,
In a dye-based ink, an increase in the viscosity of the ink due to evaporation of the ink solvent is unlikely to occur.

Therefore, the maintenance execution amount of the dark color ink is set to be larger than that of the light color ink.
Similarly, for the pigment ink, the maintenance execution amount is set to be larger than that for the dye ink. This allows
Even if the easiness of increasing the ink viscosity varies depending on the type of the ink, the maintenance execution amount appropriate for the ink can be set.

Specifically, for example, yellow,
For a head unit that uses light-colored inks such as light magenta and light cyan, a maintenance operation can be performed with a coefficient of 1 and a maintenance execution amount set based on the standby time of the recording head 4 and the like.

For a head unit that uses colored inks such as magenta and cyan, the coefficient is set to 2, and the amount of maintenance executed based on the standby time of the recording head 4 is doubled. A maintenance operation can be performed.

Further, for the head unit using the black ink, the coefficient is set to 3, and the maintenance execution amount set based on the standby time of the recording head 4 is set to 3
The maintenance operation can be performed with the doubled execution amount.

As described above, by setting the maintenance execution amount in consideration of the type of ink, it is possible to perform a detailed maintenance operation in consideration of the characteristics of the ink.

Further, in each of the above embodiments, the control unit 11 can set the maintenance execution amount in consideration of environmental information such as temperature and humidity at the place where the ink jet recording apparatus 1 is used. This takes into account that the ease of evaporation of the ink solvent depends on the temperature and humidity.

In this case, as shown in FIG. 11, a temperature sensor 51 for detecting the temperature in the use environment of the ink jet printer 1 and a humidity sensor 52 for detecting the humidity in the use environment are provided by environmental information detecting means. It is provided as. The analog temperature signal detected by the temperature sensor 51 and the analog humidity signal detected by the humidity sensor 52 are converted into digital values by A / D converters 53 and 54, and are converted into environmental information via a sensor interface 55. The data is input to the printer controller 30.

The controller 11 sets the maintenance execution amount with respect to the standby time in consideration of the input environment information (temperature information and humidity information).

For example, as shown in FIG. 12, based on the obtained environment information, the state of the use environment is classified into a low-temperature and low-humidity area A, a normal area B, and a high-temperature and low-humidity area C, and set for each area. Use the calculated coefficient.

In this case, the low-temperature and low-humidity area A has a temperature of 10 ° C.
In addition, this is a triangular area defined by a line connecting three points, a point a at 20% humidity, a point b at 10 ° C. and 35% humidity, and a point c at 15 ° C. and 20% humidity.

The normal area B has a temperature of 10 ° C. and a humidity of 35%.
Point b, temperature d 10% and humidity 80% point d, temperature 40 ° C
And a point e at 80% humidity, a point f at 40 ° C. and 35% humidity, a point g at 35 ° C. and 20% humidity, and a point c at point c at 15 ° C. and 20% humidity. This is a substantially home-based area.

The high-temperature and low-humidity area C has a temperature of 35 ° C. and a humidity of 2.
A point g of 0%, a point f of a temperature of 40 ° C. and a humidity of 35%, and
This is a triangular area defined by a line connecting three points of a point h at a temperature of 40 ° C. and a humidity of 20%.

When the condition of the use environment is within the range of the normal region B, the evaporation of the ink solvent is not so remarkable. Therefore, in this case, the maintenance operation can be performed with the maintenance execution amount set based on the standby time of the recording head 4 and the like, with the coefficient being set to 1.

On the other hand, when the condition of the use environment is in the range of the low-temperature and low-humidity area A or the high-temperature and low-humidity area C, the viscosity of the ink near the nozzle opening 17 tends to increase. Because, as for humidity, the evaporation of the ink solvent tends to be more remarkable as the humidity becomes lower, and as for the temperature, the evaporation of the ink solvent becomes more remarkable as the temperature becomes higher, and the ink viscosity tends to increase as the temperature becomes lower. Because. Therefore, in these cases, the maintenance operation can be performed with an execution amount that is twice the maintenance execution amount set based on the standby time of the recording head 4 and the like, with the coefficient being 2.

As described above, by setting the maintenance execution amount in consideration of the state of the use environment, it is possible to execute a detailed maintenance operation corresponding to the ease of evaporation of the ink solvent.

Although the ink jet printer 1 described with reference to FIG. 11 includes both the temperature sensor 51 and the humidity sensor 52, only one of the sensors may be provided. Further, a sensor other than the temperature sensor 51 and the humidity sensor 52 may be used.

Further, various additions and changes can be made to the above embodiments within the scope of the present invention described above.

For example, the pressure generating element for changing the volume of the pressure chamber 22 is not limited to the piezoelectric vibrator 21. For example, a magnetostrictive element may be used as a pressure generating element, and the pressure chamber 22 may be expanded and contracted by the magnetostrictive element to cause a pressure fluctuation, or a heating element may be used as a pressure generating element, The pressure chamber 22 may be configured to generate pressure fluctuation by bubbles that expand and contract by heat.

As described above, the printer controller 30 can be constituted by a computer system. However, a program for causing the computer system to realize each of the above-described elements and a computer-readable recording medium 201 on which the program is recorded are also included in the present invention. Is protected.

Further, when each of the above-described components is realized by a program such as an OS operating on a computer system, a program including various instructions for controlling the program such as the OS and a recording medium 202 storing the program are also provided. , Is the subject of protection in this case.

Here, the recording media 201 and 202 are not only those that can be recognized as a single unit such as a floppy disk, but also
It also includes a network for transmitting various signals.

Although the above description has been made with respect to an ink jet recording apparatus, the present invention is intended for a wide range of liquid ejecting apparatuses. Examples of liquids include
In addition to ink, glue, nail polish and the like may be used.

[0198]

As described above, according to the present invention,
Since the recovery unit is controlled based on at least a part of the elapsed time from the end of the previous operation of the recovery unit, an extremely efficient wasteless liquid thickening recovery operation according to the state of the liquid in the nozzle opening. May be implemented.

For example, when a flushing operation for discharging the liquid from the head member outside the recording area is performed as the thickening recovery operation, the amount of liquid discharged by the flushing operation can be suppressed to a minimum. Thereby, the amount of liquid that can be used for recording can be increased, and the liquid can be used effectively. Further, the capacity of the recovery material for the liquid discharged in the flushing operation can be reduced.

Alternatively, in the case of performing a micro-vibration operation for causing the meniscus to micro-vibrate by changing the pressure of the pressure chamber to such an extent that the liquid droplet is not ejected as the thickening recovery operation, the number of times of operation of the pressure generating element accompanying the micro-vibration operation is required. It can be kept to a minimum. Thus, the life of the pressure generating element can be extended.

[Brief description of the drawings]

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

FIGS. 2A and 2B are schematic diagrams illustrating a scanning range of a recording head. FIG. 2A illustrates a scanning range of a printer that performs unidirectional recording.
(B) shows the scanning range of a printer that performs bidirectional printing.

FIG. 3 is a schematic diagram for explaining the operation of the recording head;
(A) shows the state of being in the standby position, (b)
Indicates the state of moving from the standby position to the recording area side,
(C) shows the state when returning to the standby position from the recording area side, and (d) shows the state when the camera is located at the home position.

FIG. 4 is a diagram illustrating a configuration of a recording head.

FIG. 5 is a schematic block diagram illustrating an electrical configuration of a recording head.

FIG. 6 is a diagram illustrating an example of a relationship between one pass time and a maintenance execution amount.

FIG. 7 is a diagram illustrating an example of a relationship between a standby time and a maintenance execution amount.

FIG. 8 is a diagram illustrating an example of a relationship between a standby time and a maintenance execution amount when a scan amount of a print head is taken into account.

FIG. 9 is a diagram illustrating an example of a relationship between a standby time and a maintenance execution amount when a first ink droplet ejection position in a current printing operation is considered.

FIG. 10 is a diagram illustrating an example of a relationship between a standby time and a maintenance execution amount when an ink ejection ratio in a printing operation is taken into account;

FIG. 11 is a schematic block diagram illustrating an electrical configuration of a recording head when a temperature sensor and a humidity sensor of a use environment are provided.

FIG. 12 is a diagram for explaining a relationship between humidity and temperature of a place of use and an example of division of coefficient setting.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Ink-jet printer 2 Ink cartridge 3 Cartridge holder part 4 Recording head 5 Carriage 6 Guide member 7 Pulse motor 8 Drive pulley 9 Reverse pulley 10 Timing belt 11 Control part 12 Recording paper 13 Paper feed motor 14 Paper feed roller 15 Cap member 16 Nozzle Plate 17 Nozzle opening 18 Ink receiving member 20 Ink chamber 21 Piezoelectric vibrator 22 Pressure chamber 23 Ink supply port 24 Supply side communication hole 25 First nozzle communication hole 26 Second nozzle communication hole 30 Printer controller 31 Print engine 32 External interface 33 RAM 34 ROM 35 Oscillation circuit 36 Drive signal generation circuit 37 Internal interface 38 Measurement timer 39 Electric drive system of recording head 40 Shift register circuit 41 Latch circuit 42 Berushifuta circuit 43 switching circuit 51 temperature sensor 52 humidity sensor 53, 54 A / D converter 55 interface sensors

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) B41J 2/165 B41J 2/175

Claims (18)

(57) [Claims] 1. A head member having a nozzle opening and receiving ejection data corresponding to one movement in the main scanning direction, and moving the head member in the main scanning direction after the head member receives the ejection data. A head scanning mechanism for moving, a recovery unit for recovering the viscosity of the liquid in the nozzle opening, a measurement timer for measuring at least a part of an elapsed time from the end of the previous operation of the recovery unit, and a measurement timer. A liquid ejecting apparatus, comprising: a control unit that controls the number of times the recovery unit operates based on both the measured time and the ejection data. The head scanning mechanism does not move the head member in a region after the final liquid droplet has been ejected in one movement in the main scanning direction. The number of actuations of the recovery means is controlled in accordance with the next moving distance of the head member in the main scanning direction based on ejection data corresponding to the movement in the main scanning direction. 2. The liquid ejecting apparatus according to 1. 3. The head scanning mechanism does not move the head member in a region after the last liquid droplet is ejected in one movement in the main scanning direction. 2. The liquid ejecting apparatus according to claim 1, wherein the number of actuations of said recovery means is controlled in accordance with the previous moving distance in the main scanning direction. 4. The control means according to a distance until a liquid droplet is first ejected during a movement of the head member in the next main scanning direction, based on ejection data corresponding to a movement in the next main scanning direction. 2. The liquid ejecting apparatus according to claim 1, wherein the number of operations of the recovery unit is controlled. 5. A head member having a nozzle opening and receiving ejection data corresponding to one movement in the main scanning direction, and moving the head member in the main scanning direction after the head member receives the ejection data. A head scanning mechanism for moving, a recovery unit for recovering a viscosity increase of the liquid in the nozzle opening, and a head member being moved in the next main scanning direction based on ejection data corresponding to the next movement in the main scanning direction. And a control means for controlling the number of operations of the recovery means in accordance with a distance until a liquid droplet is ejected for the first time. 6. The head member has a plurality of nozzle openings, and the recovery means recovers the viscosity of the liquid at the nozzle openings for each nozzle opening. Based on the ejection data corresponding to the movement in the main scanning direction, for each nozzle opening, according to the distance until the liquid droplet is first ejected from the nozzle opening during the next movement of the head member in the main scanning direction. 6. The liquid ejecting apparatus according to claim 1, wherein the number of operations of the recovery unit is controlled. 7. The controller according to claim 1, wherein said control means controls the number of actuations of said recovery means based on the ejection data corresponding to the next movement in the main scanning direction, in accordance with the liquid ejection ratio of the head member during the next movement in the main scanning direction. The liquid ejecting apparatus according to claim 1, wherein the liquid ejecting apparatus is configured to control the liquid ejecting apparatus. 8. The head member has a plurality of nozzle openings, and the recovery means recovers the viscosity of the liquid in the nozzle opening portion for each nozzle opening. Based on the ejection data corresponding to the movement in the main scanning direction, the number of operations of the recovery unit is controlled for each nozzle opening according to the liquid ejection ratio of the head member during the next movement in the main scanning direction. The liquid ejecting apparatus according to claim 1, wherein: 9. The liquid ejecting apparatus according to claim 1, wherein the recovery means is a fine vibration means for finely vibrating the liquid at the nozzle opening. 10. The liquid ejecting apparatus according to claim 1, wherein the recovery means is a flushing means for ejecting the liquid from the head member outside the ejection area. 11. A head member having a nozzle opening and receiving ejection data corresponding to one movement in the main scanning direction, and moving the head member in the main scanning direction after the head member receives the ejection data. A head scanning mechanism for moving, a recovery unit for recovering the viscosity of the liquid at the nozzle opening, and a measurement timer for measuring at least a part of an elapsed time from the end of the previous operation of the recovery unit. A control device for controlling a liquid ejecting device, wherein the control device controls the number of operations of the recovery unit based on both the time measured by a measuring timer and the ejection data. 12. A head scanning mechanism according to claim 1, wherein the head member is not moved in an area after the last liquid droplet is ejected in one movement in the main scanning direction. Based on the ejection data corresponding to the movement, according to the moving distance of the head member in the next main scanning direction,
The control device according to claim 11, wherein the number of operations of the recovery unit is controlled. 13. The head scanning mechanism according to claim 1, wherein the head member is not moved in an area after the last liquid droplet is ejected in one movement in the main scanning direction. The control device according to claim 11, wherein the number of operations of the recovery unit is controlled according to a moving distance in a scanning direction. 14. The recovery according to a distance until a liquid droplet is first ejected during the next main scanning direction movement of the head member, based on ejection data corresponding to the next main scanning direction movement. The control device according to claim 11, wherein the number of operations of the means is controlled. 15. A head member having a nozzle opening and receiving ejection data corresponding to one movement in the main scanning direction, and moving the head member in the main scanning direction after the head member receives the ejection data. A head scanning mechanism for moving, and a recovery unit for recovering the viscosity of the liquid at the nozzle opening portion.A device for controlling a liquid ejecting apparatus, the ejection data corresponding to the next movement in the main scanning direction. The number of operations of the recovery means is controlled based on a distance until a liquid droplet is first ejected during the next main scanning direction movement of the head member. apparatus. 16. The head member has a plurality of nozzle openings, and the recovery means recovers the viscosity of the liquid in the nozzle openings for each nozzle opening. Based on the ejection data corresponding to the movement, for each nozzle opening, the recovery means according to the distance until the liquid droplet is first ejected from the nozzle opening during the movement of the head member in the next main scanning direction. The control device according to claim 11, wherein the number of times of operation is controlled. 17. The apparatus according to claim 17, wherein the number of actuations of said recovery means is controlled in accordance with a liquid ejection ratio during a movement of the head member in the next main scanning direction, based on ejection data corresponding to the next movement in the main scanning direction. The control device according to claim 11, wherein: 18. The head member has a plurality of nozzle openings, and the recovery means recovers the viscosity of the liquid at the nozzle openings for each nozzle opening. The number of actuations of the recovery means is controlled for each nozzle opening in accordance with the liquid ejection ratio during the movement of the head member in the next main scanning direction, based on the ejection data corresponding to the movement. The control device according to claim 11, wherein: