JP2001334686A - Ink jet recorder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To execute flushing operation such that reliability of printing is ensured without sacrifice of throughput regardless of the recording sheets of various widths or the print mode. SOLUTION: The ink jet recorder comprises means 51 for setting a reference level corresponding to the sheet width in correspondence with the time required for a carriage to move across the width of a set recording sheet, means 53 for setting a threshold value being used for determining necessity of flushing operation based on the reference level, a refresh timer 49 being reset by flushing operation, and means 55 for determining necessity of next flushing by comparing a threshold value set by the setting means 53 with a time measured by the refresh timer 49. Reliability of printing is ensured by lowering the reference level as the moving time of the carriage is prolonged due to the print width of a set recording sheet and the moving speed of a carriage thereby increasing the frequency of flushing operation. Furthermore, throughput is enhanced by lowering the reference value when the moving time of the carriage is short thereby decreasing the frequency of flushing operation.

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 an image on a recording sheet by moving an ink jet recording head in the width direction of the recording sheet, and more specifically, to prevent the recording head from being clogged. Flashing technology.

[0002]

2. Description of the Related Art In order to improve the throughput of an ink jet recording apparatus capable of printing on a paper width of 40 inches or more, ink receivers are arranged on both sides of a printable area and a predetermined time is set when one pass printing is completed. Each time, a so-called flushing operation is performed, in which ink droplets are ejected from the recording head to eliminate printing defects due to thickening of ink during a printing period. On the other hand, a recording apparatus capable of printing on such a large-width recording sheet requires a long time to print one image, and thus has not only a fine mode but also a draft mode capable of high-speed printing. Is configured to be capable of printing on recording paper of a small size such as A3. On the other hand, the threshold for judging the presence or absence of the flushing operation is selected to be as long as possible so as not to reduce the printing throughput. At the time when printing is started, it is necessary to execute flushing even before the flushing operation cycle arrives so that the flushing operation cycle does not arrive during the printing period of the next pass.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of such circumstances, and an object of the present invention is to reduce throughput regardless of recording papers of various widths and print modes. An object of the present invention is to provide an ink jet recording apparatus capable of executing a flushing operation so as to ensure printing reliability without any problem.

[0004]

According to the present invention, there is provided an ink jet recording head mounted on a carriage which reciprocates in the width direction of recording paper, and a flushing area is provided in a non-printing area. In an ink jet recording apparatus in which is set, a reference value setting means for setting a reference value set in accordance with a sheet width in accordance with a time when the carriage moves the sheet width of the loaded recording sheet, and Threshold value setting means for setting a threshold value for determining the required ratio of the flushing operation based on the reference value; a refresh timer reset by the flushing operation; a threshold value set by the threshold value setting means; And a flushing determining means for determining the necessity of the next flushing.

[0005]

According to the first aspect of the present invention, the reference value is decreased and the frequency of the flushing operation is increased by increasing the carriage moving time, based on the printing width of the loaded recording paper and the carriage moving speed. On the contrary, when the moving time of the carriage is short, the reference value is increased to reduce the frequency of the flushing operation, thereby improving the throughput. According to the fifth aspect of the invention, when printing is started from the home position, the probability of a flushing operation is increased as compared with the case where printing is started toward the home position, thereby preventing a decrease in throughput. When the printing is started toward, the flushing operation is performed so as not to exceed the longest flushing cycle, and the reliability of the printing can be secured.

[0006]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing the configuration of a first embodiment of the present invention. FIGS. 1 to 3 show one embodiment of a large-sized ink jet recording apparatus capable of printing on recording paper having a maximum width of 44 inches, in which a paper feed unit 1, a printing unit 2, and a paper discharge stack unit 3 are arranged. They are arranged in an upper, middle and lower positional relationship. A sheet transport path from the sheet feeding unit 1 to the sheet discharging stack unit 3 via the printing unit 2 is formed substantially straight from the obliquely upper back side to the obliquely lower front side. As shown in FIGS. 2 and 3, the paper supply section 1 is configured so that a long roll paper 4 having a maximum paper width of 44 inches can be exchangeably disposed.

The front surface of the roll paper 4 attached to the paper feed unit 1 is covered with a roll paper cover 5 which can be opened and closed, and
When the cover 5 is closed, the upper surface of the cover 5, the printing unit 2, and a discharge guide 6 described later are substantially flush with each other, so that it is possible to supply and discharge small-size cut sheets separately from the roll paper 4. It is configured to be. When printing data such as an image that is less than the maximum printable width of the recording apparatus, the paper is loaded at the home position, that is, the right end, and the printing is performed with the home position as a reference. Is executed. When printing smaller-size image data on a recording sheet having the maximum width, the printing is similarly performed based on the home position.

As shown in FIG. 2, another pair of spindle receivers 8a and 8b are disposed below the pair of spindle receivers 7a and 7b. The spindle receivers 7a, 7b, 8a, 8b are mounted on a pair of left and right frames 9, 9 in the printer body. Then, both ends of two long spindles 7 and 8 to which the roll papers 4 and 4 are respectively mounted are laid horizontally with the both ends placed between the spindle receivers 7a and 7b and between 8a and 8b. .

As shown in FIG. 2, a guide rod 10 is provided in the printing unit 2 so as to be horizontal between the left and right frames 9 and 9 and moves to the left and right in the figure. A carriage 11 is mounted so as to be able to be mounted thereon, and a first recording head 12a and a second recording head 12b are mounted on the carriage 11 side by side in the moving direction of the carriage 11.

The paper discharge stack 3 is a portion for receiving printed paper. The paper discharge stack 3 is a stack cloth 13 whose paper receiving surface is made of a foldable cloth sheet.
It is formed with. Then, the printed paper is guided to the first receiving portion 15 almost directly below the printing section 2 by the paper ejection switching lever 14 as shown in FIG. 3, or is stacked on the front floor of the printer body (not shown). It is configured such that a state in which the sheet is guided to a second receiving portion that is temporarily formed on the front side by unfolding the cloth 13 can be adopted.

Then, the printed paper is transferred to the first receiving portion 15.
In this case, the trailing edge 6a of the paper ejection guide 6 formed below the printing unit 2 and the paper ejection switching lever 14
Thus, an opening 16 is formed between the stack cloth 13 and the upper end edge 13a of the stack cloth 13 protruding on the sheet transport path.

When the printed sheet is guided to the second receiving portion, the upper edge 13a of the stack cloth 13 is retracted rearward from the sheet transport path by the discharge switching lever 14, and the stack cloth fixing lever 17 is moved. Is pulled out to the front side, and the hook 18 to which the leading end of the stack cloth 13 is fixed is engaged with the front end of the fixing lever 17, so that the stack cloth 13 can be deployed to the front side of the printer body. ing.

As shown in FIG. 2, a non-printing area (home position in this embodiment) at one end of a traveling area of the recording heads 12a and 12b mounted on the carriage 11 is provided.
Capping means 21 is provided. Recording head 1
The nozzle formation surface 2 is mounted on the carriage 11 in a state where it is slightly inclined from the vertical direction, and the capping unit 21 moves the nozzle formation surfaces of the recording heads 12a and 12b when the recording head 12 moves to the home position. Two cap members corresponding to each recording head are arranged so that the surface can be sealed. And capping means 21
Below this, a suction pump 22 for applying a negative pressure to the internal space is arranged.

The capping means 21 functions as a lid for preventing the nozzle openings of the recording heads 12a and 12b from drying during the idle period of the recording apparatus.
The negative pressure from 2 is applied to the recording heads 12a and 12b to function as a head cleaning means for sucking ink. The waste ink sucked by the suction pump 22 is discharged to a first waste ink tank 23, and is absorbed by a waste liquid absorbing material 23a stored in the tank.

On the other hand, a first flushing area 25 is formed on the moving path of the recording heads 12a and 12b adjacent to the capping means 21, and a flushing box 7 constituting an ink receiving unit is arranged here. The collected waste ink is discharged to the first waste ink tank 23 and absorbed by the waste liquid absorbent 23a.

A second flushing area 26 is also formed at the other end opposite to the capping means 21 via the central print area. Also in the second flushing area 26, a flushing box 27 is arranged, and the waste ink collected by the flushing box 27 is discharged to a second waste ink tank 28 and absorbed by a waste liquid absorbing material 28a. .

Each of the flushing boxes 7, 27 in the flushing area has a width W in the carriage running direction.
1 is smaller than the width W2 in the carriage traveling direction over the first and second recording heads 12a and 12b.

On the other hand, as shown in FIG. 3, a cartridge holder 31 in which an ink cartridge is loaded is disposed on the left and right sides of the printing unit 2 in the recording apparatus.

FIG. 4 shows an embodiment of the flushing control means of the recording apparatus. An instruction signal is supplied to a print data processing means 42 from a host computer 41 having a built-in printer driver. The command signal from the print data processing unit 42 is supplied to the head control unit 43, and the head control unit 43 supplies a head drive signal based on the bitmap data to each of the first and second recording heads 12a and 12b. Is configured. At the same time, the carriage control unit 44, which has received the command signal from the print data processing unit 42, drives the carriage motor 45 to drive the first and second recording heads 12a, 12a,
2b is reciprocated.

The physical paper width detecting means 46 which can physically detect the paper width of the recording paper mounted on the printer by, for example, a photo sensor (not shown) disposed on the carriage, A logical paper width detecting means 47 for detecting the input paper width via a printer driver is provided.

If the paper data cannot be obtained by the logical paper width detecting means 47, the paper width recognizing means 48 regards the data as the maximum paper width. Further, the smaller one compared with the sheet data obtained by the physical sheet width detecting means 46 is recognized as the sheet width. This allows
In a state where the recording paper of the A0 size is set and recognized as A0 by the physical paper width detection means 46, if the print data is small equivalent to the paper width A4 size, the logical paper width detection means 47 , A4 size paper is set, the paper width recognizing means 48 recognizes that the A4 size paper is equivalent to a state where the home position side is set as a reference position.

The refresh timer 49 starts counting from the end of the previous flushing operation or from the time when the recording heads 12a and 12b are released from the capping unit 21, and at the next flushing operation, the head control unit 43 or the carriage control unit. The clock data is cleared in response to the reset signal Re from the means 44.

The cap timer 50 starts counting when one-pass printing is completed, and is reset when the recording heads 12a and 12b are capped by the capping means 21 or when a print start trigger is issued. ing. Further, similarly to the refresh timer 49, the timer timer is cleared by receiving a reset signal Re from the head control means 43 or the carriage control means 44.

The setting means 51 is constituted by, for example, a storage means and stores numerical values shown in Table 1 set in association with the sheet width and the printing mode, that is, the carriage speed. That is, as shown in Table 1, the refresh time Rf is a value for each paper width in the high quality print mode, that is, when the speed of the carriage 11 is, for example, 200 cps, and the draft quality print mode, that is, when the speed of the carriage 11 is, for example, 300 cps. The reference value Rf * is defined for each sheet width.

[0025]

[Table 1]

The reference value Rf * is set as the difference (T-Ct) between the longest flushing period T (12.4 seconds in this embodiment) and the movement time Ct of the carriage 11 required for one-pass printing operation. Have been. These reference values Rf *
Is used in the threshold value setting means 53 to generate a threshold value for determining whether or not to execute the flushing operation when a print start is issued or when the Cap timer measures 2 seconds or more. Used.

In this embodiment, a Wait setting means 52 is provided, and when a paper or an ink whose ink is difficult to dry is used, when an input command to that effect is given from the operation panel by the user, every one pass printing is performed. In this embodiment, a pass drying time for delaying the scanning start timing of the carriage 11, that is, a parameter (Wait) of about 2 seconds in this embodiment is fetched, and a threshold value including the pass drying time is compared with the time measured by the refresh timer 49. It is determined whether flushing is to be performed or not.

That is, the parameter (Wait) outputs the next print start B and the next print start C when the printing of one pass is completed by the first print start A as shown in FIG. By providing such an idle time, the paper feeding start timing of the undried recording paper immediately after printing is delayed by the wait time, and the ink of the recording paper is shifted due to rubbing or the like. Paper feeding can be performed at a stage where the paper has been dried to an extent that is not too great.

Carriage (CR) moving direction detecting means 54
Determines whether the carriage 11 starts traveling from the home position side or starts traveling from the side opposite to the home position, and outputs data on the moving direction of the carriage 11 to the flushing determination means 55. I do.

The flushing determining means 55 compares the threshold value set by the threshold value setting means 53 with the time Rf of the refresh timer 49 to determine whether or not to execute the flushing, and to set the command signal to the flushing amount setting. The amount of ink for flushing is determined from the recording heads 12a and 12b by the head control unit 43.

The flushing position determining means 57 determines the first or second flushing area according to the running state of the carriage 11 and the paper width based on the data from the CR movement direction detecting means 54 and the paper width recognizing means 48. 25, 2
6 is determined and selected.

Next, a description will be given of the operation of determining the execution of the flushing of the apparatus configured as described above with reference to the flowchart shown in FIG. When the print start is received (step S11), after the Cap timer 49 is reset (step S12), or when the time counted by the CAP timer 49 is longer than a predetermined time, for example, 2 seconds or more (step S13). ), The setting means 51, based on the paper width from the paper width recognition means 48 and the carriage movement speed corresponding to the print mode, determines the carriage movement time Ct and the reference value Rf.
Is selected (step S14), and an operation for determining whether or not a flushing operation is performed is prepared. That is, Cap timer 4
The reason why the printing is not started at the stage where 9 has counted 2 seconds is that the print data from the host is stagnant, the recording head is exposed from the cap means, and the recording head is left without discharging ink droplets. In order to easily cause an ink droplet ejection failure, preparation for determination of a flushing operation is performed when a time of about the parameter Wait, in this embodiment, 2 seconds has elapsed. It should be noted that the recording head is sealed by the capping unit when the state where the recording head is exposed from the cap unit and no ink droplet is ejected has passed for 5 seconds.

Subsequently, the direction in which the carriage 11 is about to move is determined based on the data from the CR movement direction detecting means 54 (step S15).
Is moving from right to left, that is, from the home position side, the threshold setting means 53
A threshold value “Rf * −Ct−2 × wait” is set, and the flushing determination means 55 sets the threshold value “Rf * −Ct−
2 × wait ”is compared with the counted time Rf of the refresh timer 49 (step S16).

On the other hand, when the carriage 11 moves from left to right, the threshold value setting means 53 sets a threshold value "Rf *", and the flushing determination means 55 sets the threshold value "Rf *" and the refresh timer. The measured time Rf is compared with the measured time Rf of 49 (step S17).

These steps S16 and S17
In any one of the above, when the counted time Rf of the refresh timer 49 has exceeded the threshold value set by the threshold value setting means 53, the flushing operation is determined (step S18).

By the way, the threshold "Rf * -Ct-2.times." When the carriage 11 moves from right to left in the next printing (when moving from the home position).
Since “wait” is smaller than the threshold “Rf *” when the carriage 11 attempts to move from left to right, when the movement starts from the home position side, the count time Rf of the refresh timer 49 is short. , The probability of executing the flushing at the home position located on the right side is increased, and the throughput can be improved.The parameter wait is doubled to secure a margin. , Can be set to an appropriate magnification.

Next, in order to prevent printing defects, it is necessary to execute the flushing operation during the printing period at the longest within 12.4 seconds, and the carriage in the printing mode, ie, the high quality printing mode and the draft printing mode. When the moving speed is set to 200 cps and 300 cps, respectively, the above-described example of the printing apparatus in which the moving time of the carriage 11 required for printing in one pass for each size of paper is the value shown in Table 2 is used. The determination operation will be specifically described.

[0038]

[Table 2]

When the A0 recording paper is loaded and the print mode is set to the high quality print mode, the setting means 51 determines the carriage movement time based on the print mode and the paper width from the paper width recognition means 48. "2" is selected as Ct, and 10.4 is selected as the reference time Rf * (step S14). The CR moving direction detecting means 54
When it is determined that the moving direction of the camera is to start from the right to the left, that is, from the home position (step S15), the threshold setting unit 53 determines that “Rf * −Ct−2 × wait” = (10.4)
−2-2 × wait) = (8.4-2 × wait), and the flushing determination unit 55 sets the threshold “R
f * -Ct−2 × wait ”is compared with the counted time Rf of the refresh timer 49 (step S16).

In this case, since the printing is for the first pass, the counted time Rf of the refresh timer is the threshold value (8.4-2 ×
wait), and thus start printing without performing flushing. When the printing head moves to the left end side after one-pass printing is completed, the setting unit 51 sets the threshold value of “Rf *” = (10.4), and the flushing determination unit 55 sets the threshold value of “Rf *” = (10.4). Then, the threshold value (10.4 + 2) is compared with the counted time Rf of the refresh timer 49 (step S17).

As described above, in printing from the home position side, the count time R of the refresh timer 49 is used.
When f exceeds (8.4-2 × wait), the flushing operation is determined (step S18), and the flushing is executed by the steps shown in the flowcharts of FIGS.

Also, in printing from the opposite side of the home position, the counted time Rf of the refresh timer 49 is
After (10.4), the flushing operation is determined (step S18), and the flushing is executed by the steps shown in the flowcharts of FIGS.

This reference value Rf * is the same as the longest flushing cycle T and 1 even in printing on other papers or print modes.
When the printing is started from the opposite side of the home position, the flushing operation is performed before the longest flushing period T during the printing, since the difference is set as the difference from the movement time Ct of the carriage 11 required for printing the pass. Can be started. The longest flushing cycle T is a time period until the occurrence of an ink droplet ejection failure, for example, a bend in the flight direction of the ink droplet, unless the flushing operation is performed again at least before the time T arrives from the end of the previous flushing operation. It is. For example, if the carriage is 200
Taking as an example a case where the paper is moved by a distance of the paper width A0 at a speed of cps, the reference value Rf * is 10.4 from Table 1. Further, in a state where the refresh timer 49 measures 10.3 seconds as the measurement time Rf and printing is to be started from the side opposite to the home position, the measurement time Rf = 10.3 is equal to the reference value Rf * = 10. .4, the determination in step S17 is negative (N), and the flushing operation is not performed. Since the movement time Ct of the carriage is 2 seconds, the refresh timer 49 measures the time Rf = 12.3 (seconds) when the carriage reaches the home position. Therefore, regardless of the carriage moving speed and the paper width, the reflash timer 49 measures the time T during the printing period, and the time does not increase, and the ink droplet ejection failure does not occur.

On the other hand, when printing is started from the home position side, the threshold value is (Rf * -Ct-2wai).
t) is set, and the value of the threshold (Rf * -Ct-2wait) changes according to the width of the loaded recording paper and the carriage movement time Ct and the reference value Rf * according to the print mode. Compared to the case where printing is started from the opposite side to the home position to the home position, the threshold value is (C
Since it is set to be smaller by (t + 2wait), the probability of determining whether or not flushing has been executed in the area on the home position side increases. For this reason, when printing is performed based on the home position side, the time at which the next print start is issued becomes unclear due to a delay in data transmission from the host, etc. Even in such a case, the probability of judging the presence or absence of the flushing operation at the home position is increased, and the throughput is improved. In particular, in the case of print data in which the width of the print data is smaller than the physical paper width of the loaded recording paper, the throughput is greatly improved.

In other words, when the paper width is almost the same, the higher the moving speed of the carriage, the larger the reference value Rf * is set and the shorter the moving time Ct of the carriage becomes.
The frequency of the flushing operation is reduced, and the throughput is improved. Conversely, the slower the moving speed of the carriage, the longer the moving time. Therefore, the frequency of the flushing operation is increased to ensure the reliability of printing.

FIGS. 6 and 7 show details of the flushing operation subsequent to FIG. 5. In step S31 starting at (A) in FIG. 6, the flushing number is set. This is performed by the flushing amount setting means 56 in FIG. In this embodiment, the flushing number is “Fb = 48, Fy = 3
6 "is set, and 48 shots are set for the first head 12a that handles black, cyan, and magenta inks, and 36 shots are set for the second head 12b that handles yellow, light cyan, and light magenta inks.

Subsequently, in step S32, it is determined whether or not the number of shots of the ink droplets ejected from the two cap members disposed on the capping means 21 has reached a predetermined number or more. Here, in the case where each of the two cap members has reached 60,000 shots or more, the regular empty suction is executed without shifting to the flushing operation. Thus, the ink in the cap member is sucked by the suction pump 22 and discharged to the waste ink tank 23. At the same time, the counter that counts the number of shots of ink droplets ejected from the two cap members is cleared.

If it is determined in step S33 that the predetermined number of shots has not been reached, the direction in which the carriage 11 is to move in the next printing is determined in step S34. Here, when the carriage 11 is going to move from right to left, step S35 is performed.
, Flushing is performed on the flushing box 7 on the right side. In this case, as shown in step S36, the first and second heads 12a and 12b perform step S31.
The number of shots (Fb, Fy) set in step (1) is flashed, and the number of flushing is counted up in step S37.

In the subsequent step S38 in FIG. 7, it is determined whether or not the flushing number in the right flushing box 7 exceeds a predetermined number.
Here, if it is determined that the number of shots exceeds 12,500, in step S39, "1" is added to the count number "A" of the waste liquid box, and the count value of the flushing number in the right flushing box is reset. Subsequently, in step S40, the count value of the refresh timer 49 is reset, and counting of time is started immediately thereafter.

Then, the process proceeds to step S41 where ink detection is performed. In this step, the recording head 12
The ink consumption of the ink cartridge is integrated based on the number of inks ejected from a and 12b, and it is determined in step S42 whether the integrated value has reached a specified value. If the value has not reached the specified value, the process is returned.
If it is determined that the recording value has reached the specified value, the process proceeds to step S43, in which the carriage 11 moves to the home position, and the recording head is sealed by the capping unit 21.
An error message (Ink-Out) is displayed on the display.

Returning to FIG. 6, if it is determined in step S34 that the carriage 11 is going to move from left to right in the next printing, it is determined in step S51 whether the carriage 11 is to the left of [B]. .
[B] is a critical position for determining which of the flushing boxes 7 and 27 the carriage 11 moves to can reach the flushing box in a short time because the flushing box exists at two places on the left and right. If the determination in step S51 is Yes, the process proceeds to step S52, where the flushing box 2 on the left side
7. The flushing is executed.

Then, the process proceeds to step S53, in which the number of shots (Fb, Fy) set in step S31 is flushed from the first and second heads 12a, 12b, respectively. In step S54, the number of flushing in the flushing box 27 on the left side is reduced. Counted up.

Subsequently, in step S55, it is determined whether or not the number of flushing in the left flushing box 27 exceeds a predetermined number. If it is determined that the number of flushing exceeds, for example, 60,000 shots, the flow proceeds to step S56. , "1" for the count number "D" in the left waste box
To reset the count value of the flushing number of the flushing box 27 on the left side. Thereafter, the flow shifts to step S38 shown in FIG.

If it is determined as No in step S51, the process proceeds to step S57, and flushing is performed in the flushing box 7 on the right side. Then, the process proceeds to step S58, where the first and second heads 12a, 12a
b to the number of shots (F
b, Fy) are respectively discharged, and the number of flushing is counted up in step S59. Subsequently, the operation proceeds to step S60, where an operation of returning the carriage to the original position during printing is performed, and thereafter, the operation proceeds to step S38 shown in FIG.

[0055]

As described above, according to the present invention, the reference value for setting the reference value set in accordance with the paper width of the loaded recording paper in accordance with the time for moving the carriage. Value setting means, threshold value setting means for setting a threshold value for determining a required ratio of the flushing operation based on the reference value, a refresh timer reset by the flushing operation, a threshold value set by the threshold value setting means and a refresh timer Flushing determination means for comparing the measured time with the flushing time to determine the necessity of the next flushing, so that the longer the moving time of the carriage becomes, By lowering the reference value and increasing the frequency of the flushing operation, the reliability of printing can be ensured. It is possible to improve the throughput by reducing the frequency of flushing operation by increasing the value.

[Brief description of the drawings]

FIG. 1 is a perspective view showing one embodiment of an ink jet recording apparatus of the present invention.

FIG. 2 is a front view mainly showing a printing mechanism of the recording apparatus.

FIG. 3 is a sectional view showing a structure of a flushing region.

FIG. 4 is a block diagram showing one embodiment of a flushing control unit in the ink jet recording apparatus.

FIG. 5 is a flowchart illustrating an operation of determining whether flushing is required.

FIG. 6 is a flowchart showing a flushing operation.

FIG. 7 is a flowchart showing a flushing operation.

FIG. 8 is an explanatory diagram of idling in a printing process. DESCRIPTION OF SYMBOLS 1 Paper feed part 2 Printing part 12a, 12b Recording head 21 Capping means 22 Suction pump 23 Waste ink tank 25, 26 Flushing area

Claims (7)

[Claims] An ink jet recording head mounted on a carriage that reciprocates in the width direction of the recording paper;
In an ink jet recording apparatus in which a flushing area is set in a non-printing area, a reference for setting a reference value set in accordance with a sheet width of the loaded recording sheet in accordance with a time for moving the carriage. Value setting means, threshold value setting means for setting a threshold value for determining a required ratio of a flushing operation based on the reference value, a refresh timer reset by the flushing operation, and a threshold value set by the threshold value setting means. A flushing determining unit for comparing the time measured by the refresh timer to determine whether the next flushing is necessary or not. 2. The ink jet recording apparatus according to claim 1, wherein the reference value is set corresponding to a sheet width. 3. The ink jet recording apparatus according to claim 1, wherein the reference value is set according to a moving speed of the carriage. 4. The ink jet recording apparatus according to claim 1, wherein the reference value is set as a difference between a longest flushing cycle and a time required for the carriage to move the width of the recording paper to be loaded. 5. The printing apparatus according to claim 1, wherein the recording sheet is mounted with the home position side as a reference position, and the threshold value setting means sets a threshold value when starting to move from the home position and printing based on the reference value. 2. The ink jet recording apparatus according to claim 1, wherein the setting is made smaller than a threshold value when printing is started toward. 6. The ink jet recording apparatus according to claim 5, wherein the threshold when printing is started from the home position is set as a difference between the reference value and a predetermined value. 7. The flushing area is formed in a first flushing area arranged in a non-printing area on the home position side and a second flushing area arranged in a non-printing area facing the home position. 2. The flushing position determining unit according to claim 1, further comprising: a flushing position determining unit that determines which of the first and second flushing areas is to be flushed when it is determined that flushing is necessary after the printing of the pass. Ink jet recording device.