JP6859045B2 - Inkjet recording device and cleaning method - Google Patents

Description

The present invention relates to an inkjet recording device that ejects ink from a recording head to record an image and a cleaning method thereof.

In the inkjet recording apparatus disclosed in Patent Document 1, the ink adhering to the recording head is removed by wiping the ink ejection surface of the recording head after the recording operation is completed. Further, after wiping, by driving the pump with the cap for covering the ink ejection surface of the recording head removed, ink is sucked from the cap and the tube connected to the cap, so-called air suction is performed. When the air suction is completed, capping is performed to cover the ink ejection surface with a cap, so that it is possible to prevent the ink ejection failure caused by the ink ejection surface becoming dry and the ink sticking.

JP-A-2015-36223

However, in the configuration of Patent Document 1, wiping, air suction, and capping are performed each time the recording operation is completed. Therefore, if the next recording operation is desired to be performed shortly after the previous recording operation is completed, the next recording operation is performed. It may make the user wait before it starts.

In view of such circumstances, it is an object of the present invention to provide an inkjet recording apparatus that performs an appropriate cleaning operation according to an interval at which a recording operation is performed.

In order to achieve the above object, the present invention has a receiving means for receiving a recording job command and a discharge port surface provided with a plurality of ejection ports for ejecting ink, and the recording job command received by the receiving means. The recording head that performs the recording operation based on the recording operation, the cleaning means for cleaning the discharge port surface, and the waiting time during which the recording operation by the recording head has not been performed since the recording operation based on the previous recording job command is completed are the first. Control to cause the cleaning means to perform the first cleaning operation when the threshold value of 1 elapses, and to cause the cleaning means to perform the second cleaning operation when the waiting time elapses with a second threshold value larger than the first threshold value. and means, storage means for storing a job interval from the recording operation based on the recording job instructions past the ends until it receives the next printing job instruction of the recording job command, wherein the control means, When the waiting time is less than the second threshold value and the job interval is equal to or greater than a predetermined value, the cleaning means is made to perform the second cleaning operation without performing the first cleaning operation. And.

According to the present invention, there is provided an inkjet recording apparatus that performs an appropriate cleaning operation according to the interval at which the recording operation is performed.

It is a schematic diagram which shows the inkjet recording apparatus which concerns on 1st Embodiment. It is a figure which shows the recording head unit which concerns on 1st Embodiment. It is a schematic diagram which shows the purge unit which concerns on 1st Embodiment. It is a block diagram which shows the control configuration which concerns on 1st Embodiment. It is a flowchart which shows the control of the cleaning operation which concerns on 1st Embodiment. It is a flowchart which shows the control of the 1st cleaning operation and the 2nd cleaning operation which concerns on 1st Embodiment. It is a flowchart which shows the control of the cleaning operation which concerns on 2nd Embodiment. It is a flowchart which shows the control of the cleaning operation which concerns on 3rd Embodiment.

An embodiment of the inkjet recording apparatus according to the present invention will be described. However, the components described in the embodiments are merely examples, and are not intended to limit the scope of the present invention. In the present specification, an example is a serial type inkjet recording device in which a head that ejects ink to a recording medium that is intermittently conveyed is reciprocated in a direction that intersects the conveying direction of the recording medium to perform recording. explain. However, the present invention is not limited to the serial type inkjet recording device, and can be applied to a line type inkjet recording device that continuously prints using a long print head. In the present specification, "ink" is used as a general term for liquids such as recording liquids. Further, in the present specification, the term "record" includes not only a record for a two-dimensional object but also a record for a three-dimensional object. As used herein, the term "nozzle" is a general term for an ejection port, a liquid passage communicating with the ejection port, and an element for generating energy used for ink ejection. In the present specification, the "recording medium" is a medium that discharges a liquid, and is used as a general term for recording media such as paper, cloth, plastic film, metal plate, glass, ceramics, wood, and leather. Further, the recording medium is not limited to cut paper, but also includes roll-shaped continuous paper.

[First Embodiment]
FIG. 1 is a schematic view showing an inkjet recording device (hereinafter, recording device) 10 according to the present embodiment. The recording device 10 mainly includes a recording head unit 100, a carriage 40, a paper feeding unit (not shown), and a purge unit 20. The carriage 40 is supported by a support rail 60 or the like, and is mounted on the recording head unit 100 and reciprocates in the X direction (main scanning direction) shown in FIG.

A paper feed tray 50 is provided on the bottom surface of the recording device 10 to hold a recording medium used for recording. The recording medium loaded on the paper feed tray 50 is fed into the recording device 10 by the paper feed unit. The fed recording medium is conveyed in the Y direction (conveyance direction) shown in FIG. 1 by a transfer roller 8 or the like. A platen 19 is arranged at a position facing the recording head 110 on the downstream side of the transport roller 8. The platen 19 supports the conveyed recording medium from below in the vertical direction (Z direction). By ejecting ink from the recording head 110 while the carriage 40 moves in the X direction, an image for one band is formed on the recording medium. When an image for one band is formed on the recording medium, the recording medium is conveyed in the Y direction by a predetermined amount by a transfer roller 8 or the like (intermittent transfer). By repeating the image formation for one band and the intermittent transfer operation, an image is formed on the entire recording medium. In the present specification, the “recording operation” refers to a series of operations from the time when the recording medium is fed into the recording device 10 to the time when an image is formed and discharged to the outside of the recording device 10.

FIG. 2 is an enlarged view showing the details of the recording head unit 100. FIG. 2A is a top perspective view of the recording head unit 100, and FIG. 2B is a bottom perspective view of the recording head unit 100. The recording head unit 100 includes a recording head 110 that ejects ink and an ink tank 160 that supplies ink to the recording head 110. The ink tank 160 is detachably mounted on the recording head 110. In this embodiment, four independent ink tanks 160 are mounted: a yellow ink tank 160Y, a black ink tank 160Bk, a cyan ink tank 160C, and a magenta ink tank 160M. Although four colors of ink are used in the present embodiment, the present invention is not limited to this. For example, among these, inks of three or less colors may be used, or inks of other colors may be added and inks of four or more colors may be used. The inks of other colors are, for example, gray ink, pigment black ink, light cyan ink and the like.

As shown in FIG. 2B, the ejection port surface 120 of the recording head 110 is provided with an ejection port row in which the ejection ports for ejecting ink are arranged for each color. Two types of discharge port surfaces 120 are provided: a black discharge port surface 120Bk having a black discharge port row and a color discharge port surface 120Cl having a discharge port row for the remaining three colors. The discharge port surface 120Bk and the discharge port surface 120Cl are provided on the base substrate 130.

FIG. 3 is an enlarged view showing the details of the purge unit 20. The purge unit 20 is provided in the moving area of the carriage 40 and outside the area (recording area) in which recording is performed on the recording medium. The purge unit 20 mainly includes a tube 21, a motor (not shown), a tube pump 22, a cap 23, and a wiper 24.

The cap 23 is configured to be able to abut (capp) or separate from the discharge port surface 120 of the recording head 110 by moving up and down in the Z direction (vertical direction) shown in FIG. The cap 23 has a black cap 23Bk and a color cap 23Cl corresponding to the two discharge port surfaces 120 described above, and these move integrally. By integrally moving the cap 23 including the black cap 23Bk and the color cap 23Cl upward vertically, the discharge port surface 120 of the recording head 110 can be integrally covered and capped.

A tube 21 is connected to the cap 23, and a tube pump 22 is arranged in the tube 21. The tube pump 22 is provided with a rotating body (not shown), and by rotating the rotating body, the tube 21 can be pushed and a negative pressure can be generated inside the tube 21. When the tube pump 22 is driven with the cap 23 capping the discharge port surface 120, the inside of the cap 23 is made a negative pressure and ink can be sucked from the discharge port. The sucked ink is discharged to a waste ink absorber (discharging portion) (not shown) via the tube 21. By sucking and discharging the air bubbles and the thickened ink mixed in the ink in this way, the ink ejection state of the recording head 110 can be maintained satisfactorily.

Further, the pre-discharge operation of the recording head 110 is performed in a state where the cap 23 is separated from the discharge port surface 120 at a position facing the discharge port surface 120. The preliminary ejection operation means ejecting ink that does not contribute to the recording operation from the recording head 110 and ejecting thickened ink or the like. The pre-discharge operation is performed after the wiping operation described later or during the recording operation. The pre-discharged ink is received by the cap 23. When a predetermined amount of ink is pre-discharged to the cap 23 by the pre-discharge operation, an air suction operation of sucking the pre-discharged ink into the cap 23 is performed by driving the tube pump 22. As a result, the ink accumulated in the cap 23 is discharged.

A wiper 24 is provided adjacent to the cap 23. The wiper 24 has a base wiper 24a that wipes the base substrate 130 and a nozzle wiper 24b that wipes the discharge port (nozzle) surface 120. The wiper 24 wipes (wiping) the discharge port surface 120 and the base substrate 130 by moving the discharge port surface 120 toward the a direction shown in FIG. 3 by a drive source (not shown) at a position where the discharge port surface 120 faces the cap 23. To do. When the wiping operation is completed, the carriage 40 retracts from the position facing the cap 23, and then the wiper 24 moves in the direction opposite to the a direction shown in FIG. 3 and returns to the original position.

FIG. 4 is a block diagram showing a control configuration according to the present embodiment. The ROM 4001 stores a control program to be executed, each setting value in the control, and the like. The RAM 4002 is used for data expansion when executing a control program, storage of print data and control instructions, storage of control variables in each control, and the like. The timer circuit 4003 is a circuit capable of acquiring information about the current time or a circuit capable of measuring the elapsed time. The non-volatile memory 4004 can store parameters and the like used in the control even when the power of the main body is turned off, and in the control in the present embodiment, it is used for writing and reading the time that is the starting point when calculating the standby time. Used. The control circuit 4000 executes a control program stored in the ROM 4001 and a control program expanded in the RAM 4002. The sequence executed in this embodiment is a part of the sequence executed by the control program described above.

The external connection circuit 4005 is a circuit for the control circuit 4000 to handle the interface and the control signal when the recording device 10 main body and the external host device communicate with each other by wire or wirelessly. The recording device 10 receives a recording job instruction from an external host device via the external connection circuit 4005. The recording job instruction includes image data to be recorded. When the recording device 10 receives the recording job command, the recording device 10 performs a recording operation on the above-mentioned recording medium based on the image data. This series of operations from receiving the recording job command to discharging the recording medium to the outside of the recording device 10 by the recording operation is called a "recording job". It should be noted that even when the recording operation is performed on a plurality of recording media based on one recording job command, it is one recording job. Further, the current time may be input to the recording device 10 via the external connection circuit 4005.

The control circuit 4000 expands the received image data into the RAM 4002. Further, the control circuit 4000 controls the drive of the recording head unit 100 via the recording head unit drive circuit 4006 based on the data developed on the RAM 4002. At the same time, the control circuit 4000 controls the drive of the carriage motor 4011 via the carriage motor drive circuit 4010. By controlling one recording operation by the control circuit 4000, ink is ejected from the recording head 110 to a desired position on the recording medium when the carriage 40 is moving, and an image for one band is formed on the recording medium. Further, the control circuit 4000 intermittently conveys the recording medium by controlling the transfer motor 4013 via the transfer motor drive circuit 4012.

The control circuit 4000 controls the purge motor 4009 via the purge motor drive circuit 4008 to perform a suction operation of sucking a predetermined amount of ink from the recording head 110. By controlling the purge motor 4009, the cap 23 also performs a capping operation on the discharge port surface 120 and the wiper 24 also performs a wiping operation on the discharge port surface 120. Further, the control circuit 4000 performs a preliminary discharge operation by controlling the drive of the recording head unit 100 via the recording head unit drive circuit 4006. The pattern for driving the recording head 110 in this case is based on either the data developed on the RAM 4002, the data on the ROM 4001, or the data generated by the control circuit 4000, as in the recording operation described above. ..

Next, a flowchart showing control regarding the cleaning operation according to the present embodiment will be described with reference to FIGS. 5 and 6. Here, the cleaning operation is a general term for a wiping operation, an air suction operation, a preliminary discharge operation, and a capping operation. In the present embodiment, these cleaning operations are performed based on the job interval T, which indicates the time from the end of the recording operation based on the recording job instruction two times before to the reception of the previous recording job instruction. That is, the cleaning operation performed during the waiting time after the end of the current recording job is controlled based on the job interval T between the recording job two times before and the previous recording job. Here, the waiting time is a time for starting counting after the recording job is completed, and indicates a time in which the recording device 10 is waiting until the next recording job instruction is received. FIG. 5 is a flowchart showing a process from receiving a recording job command to ending the cleaning operation with a capping operation.

First, when a recording job command is received from an external host device, the recording operation sequence is executed in S101. At the end of the recording operation, the standby time is reset in S102 and counting is started from 0. In S103, it is determined whether or not the waiting time is equal to or greater than the first threshold value. If the waiting time is less than the first threshold value, the waiting time count is continued. When the waiting time is equal to or greater than the first threshold value, S104 determines whether or not the job interval T is equal to or greater than the second threshold value (predetermined value). Further, the second threshold value is larger than the first threshold value, and in the present embodiment, the first threshold value is 1 minute and the second threshold value is 10 minutes.

If the job interval T is equal to or greater than the second threshold value in S104, the process proceeds to S107 without performing the first cleaning operation, the second cleaning operation is executed, and the process ends. On the other hand, when the job interval T is less than the second threshold value in S104, the first cleaning operation is executed in S105. When the first cleaning operation is completed, it is determined in S106 whether or not the waiting time during which the count has been continued is equal to or greater than the second threshold value. If the waiting time is less than the second threshold, the waiting time count is continued. If the waiting time has passed the second threshold value, the second cleaning operation is executed in S107 to end the sequence. Although the job interval T is compared with the second threshold value in S104, the present invention is not limited to this, and a threshold value different from the second threshold value may be compared.

FIG. 6 is a flowchart illustrating the first cleaning operation and the second cleaning operation shown in FIG. FIG. 6A shows the first cleaning operation, which is executed in S105 in the flowchart of FIG. In the first cleaning operation, first, in S110, it is determined whether or not the dot count value N of the recording head 110 is larger than the threshold value N2. The dot count value N is a calculation of the number of times ink is ejected from the ejection port of the recording head 110. The larger the dot count value N, the finer the ink mist scattered when the ink is ejected in the recording operation on the ejection port surface 120. It is more likely to adhere. In order to prevent ink ejection defects from occurring due to the adhered ink mist, when the dot count value N exceeds the threshold value N2 (predetermined number of times), a wiping operation is performed on the ejection port surface 120 to set the dot count value N to 0. Reset to. In the present embodiment, the threshold value N2 of the black ejection port is 3.5 × 10 ^ 7 dots, the threshold value N2 of the color ejection port is 5.5 × 10 ^ 7 dots, and the threshold values for the black ink and the color ink are respectively. N2 is defined.

If the dot count value N is less than the threshold value N2 in S110, the process proceeds to S113 without performing the wiping operation. On the other hand, when the dot count value N is larger than the threshold value N2 in S110, the wiping operation is performed in S111 and the preliminary discharge operation is performed in S112. The preliminary ejection operation performed here is performed in order to prevent the ink from being pressed against the ejection port by the wiping operation and causing color mixing of the ink. When the preliminary discharge operation is completed, the process proceeds to S113.

In S113, it is determined whether or not the amount of ink (preliminary ejection ink amount) W pre-ejected in the preliminary ejection operation so far is larger than the threshold value W1 (predetermined amount). Since the ink pre-discharged in the pre-discharge operation is received by the cap 23, when the amount of ink exceeding the threshold value W1 is pre-discharged, the ink is capped with the ink accumulated in the cap 23, so that the ink is printed on the ejection port surface 120. May adhere. Therefore, when the preliminary ejection ink amount W exceeds the threshold value W1 in S113, the first empty suction operation of sucking the volume of the cap 23 is performed. When the first air suction operation is performed, the count of the preliminary ejection ink amount W is subtracted by a predetermined amount. The purpose of the first suction is to suck and discharge the ink remaining in the cap 23, and the ink remaining in the tube 21 connecting the cap 23 and the waste ink absorber is not sufficiently sucked and discharged. by. The count of the pre-discharge ink amount W is reset to 0 by the second air suction operation described later.

On the other hand, if the preliminary ejection ink amount W does not exceed the threshold value W1 in S113, the process proceeds to S115. The amount of pre-discharged ink is calculated from the number of times the ink is pre-discharged in the pre-discharge operation, that is, the dot count value in the pre-discharge operation. Further, the threshold value W1 used in this embodiment is 50 × 10 ^ 6 ng.

In S115, a capping operation is performed to end the sequence of the first cleaning operation. In S110, it was determined whether or not to perform the wiping operation according to the dot count value, but the present invention is not limited to this, and the wiping operation is performed according to the recording duty of the pattern recorded on the recording medium. May be good.

The first cleaning operation described above is an operation for performing capping by performing the minimum necessary cleaning operation in order to prevent the discharge port surface 120 from drying. Therefore, by always performing the second cleaning operation after the first cleaning operation, the wiping operation, the air suction operation, the preliminary discharge operation, and the capping operation are all controlled to be performed. Since the main purpose of the first cleaning operation is the capping operation, if the dot count value N and the preliminary ejection ink amount W do not exceed the respective threshold values in the judgments in S110 and S113, only the capping operation is performed. Therefore, the time until the capping operation can be shortened as compared with the case where all the cleaning operations are performed after the recording operation is completed or the second cleaning operation is performed.

Since the first cleaning operation is performed when the job interval T is less than the second threshold value (10 minutes), the user who has a short recording job instruction interval (job interval) starts the next recording operation. The waiting time required is reduced. Therefore, the throughput is improved when the continuous recording operation is performed, and the usability of the user is also improved.

Further, in the first air suction operation in S114, the volume of the cap 23 is sucked and discharged, so that the time required for the air suction operation can be shortened and the durability of the tube pump 22 can be improved. In the present embodiment, the preliminary ejection ink amount W and the threshold value W1 are compared only once in S113. The air suction operation may be performed with a plurality of types of intensities by changing the driving time and the like.

FIG. 6B shows a second cleaning operation, which is executed in S107 in the flowchart of FIG. First, it is determined in S120 whether or not the wiping operation is performed in the first cleaning operation. When the wiping operation is performed in the first cleaning operation, the second air suction operation is performed in S126. Here, unlike the first air suction operation, the second air suction operation sucks and discharges the ink remaining not only in the cap 23 but also in the tube 21. Therefore, the tube pump 22 is driven for a longer time than the first air suction operation to perform suction. Further, the second air suction operation performed in S126 is performed in the capped state in the first cleaning operation. As a result, the time for moving the cap 23 in the vertical direction can be omitted, and the discharge port surface 120 can be prevented from drying. When the second air suction operation is performed, the preliminary ejection ink amount W is reset to 0, and the sequence ends.

On the other hand, when the wiping operation is not performed in the first cleaning operation, it is determined in S121 whether the cap 23 is in the open state, that is, whether the cap 23 is separated from the discharge port surface 120. When the cap 23 is not in the open state, that is, in the capping state, the cap is opened in S122. On the other hand, if the cap 23 is in the open state, the process proceeds to S123. A wiping operation is performed on the discharge port surface 120 in S123, and then a preliminary discharge operation is performed in S124. After that, the second air suction operation is performed in S125. Here, the second air suction operation in S125 has the same purpose as the second air suction operation in S126, except that it is performed in the cap open state. In S125, by performing the second air suction operation with the cap open, even if ink is accumulated in the cap 23 due to the preliminary ejection operation performed in S124, the ink in the cap 23 is sucked before the capping operation is performed. Can be discharged. Therefore, it is possible to suppress the ink ejection failure generated by the ink accumulated in the cap 23 adhering to the ejection port surface 120. When the second air suction operation is performed, the preliminary ejection ink amount W is reset to 0, and the capping operation is performed in S127 to end the sequence. When the second cleaning operation is completed, the waiting time is reset to 0.

The second cleaning operation described above is performed when the recording job command is not received for a predetermined time after the first cleaning operation is performed. Specifically, it is performed when the waiting time exceeds the second threshold value (10 minutes). When the wiping operation is performed in the first cleaning operation, the wiping operation and the preliminary discharge operation are not performed, so that the time required for the second cleaning operation can be shortened. Further, since the useless preliminary ejection operation can be omitted, the waste liquid of the ink can be reduced. In the present embodiment, the control is such that the capping operation is performed after the first air suction operation and the second air suction operation, but the control is not limited to this, and the cap 23 remains in the capped state after the capping operation. It may be configured to perform an air suction operation or a second air suction operation.

With the above-mentioned control, especially for a user having a short job interval T, the time required for the cleaning operation to be performed until the next recording operation can be shortened, and the usability can be improved. Further, for a user having a long job interval T, the first cleaning operation is skipped and the second cleaning operation is performed, so that the number of cleaning operations can be reduced to one. Further, the time required for the cleaning operation can be shortened.

The job interval T in the present embodiment uses the job interval between the recording job two times before and the previous recording job, but the job interval T is not limited to this and may be any job interval between continuous recording jobs. If the second recording job is received while the first recording job is being executed, the job interval is counted as 0 seconds.

[Second Embodiment]
In the first embodiment, the control is performed based on the job interval for one time, but in the present embodiment, the control is performed based on the average job interval Ta obtained by averaging the past job intervals. The basic configuration is the same as that of the first embodiment, and the fish during the first cleaning operation and the second cleaning operation are the same as those shown in FIG.

FIG. 7 is a flowchart showing control regarding the cleaning operation of the present embodiment. S201 to S203 perform the same control as S101 to S103 shown in FIG. 5 of the first embodiment. In S204, it is determined whether or not the average job interval Ta is equal to or greater than the second threshold value. Here, the average job interval Ta indicates an average value of intervals between continuous recording operations, and examples of the calculation method include arithmetic mean. However, the calculation method is not limited to this, and may be, for example, a geometric mean, an adjusted average, a harmonic mean, a weighted average weighted to the latest recording interval, a mode, or the like.

If the average job interval Ta is equal to or greater than the second threshold value in S204, the second cleaning operation is performed in S207 without performing the first cleaning operation, the waiting time is reset to 0, and the sequence ends. .. If the average job interval Ta is less than the second threshold value in S204, the first cleaning operation is performed in S205. When the first cleaning operation is completed, it is determined in S206 whether or not the waiting time during which the count has been continued is equal to or greater than the second threshold value. If the waiting time is less than the second threshold, the waiting time count is continued. If the waiting time exceeds the second threshold value, the second cleaning operation is executed in S207 to reset the waiting time to 0 and end the sequence.

As described above, by controlling the cleaning operation to be executed based on the average job interval Ta, it is possible to execute the cleaning operation more suitable for the user's usage in addition to the effect obtained in the first embodiment. The average job interval Ta may be calculated from all past job intervals or from the most recent predetermined number of job intervals.

[Third Embodiment]
In the present embodiment, when the second threshold value is used as a reference, it is first determined whether the job interval is longer or shorter than the second threshold value, and the job interval is shorter than the second threshold value. The cleaning operation is controlled based on whether or not the number of jobs is larger than the threshold value P. That is, control is performed based on whether or not the ratio of the number of short-time recording jobs Mc whose job interval is shorter than the second threshold value to the past cumulative number of jobs is equal to or greater than a predetermined value. Further, these controls are performed after the cumulative number of recorded jobs M, which is the number of jobs received in the past, exceeds a predetermined threshold value Mth. The cumulative number of recorded jobs M may be the total number of recorded jobs up to now or the cumulative number of recorded jobs in a predetermined period. That is, after performing the recording operation for the number of recording jobs that can statistically determine the usage tendency of the user, the cleaning operation to be executed is selected. The control regarding the cleaning operation of the present embodiment will be specifically described with reference to FIG. The basic configuration is the same as that of the first embodiment and the second embodiment, and the control of the first cleaning operation and the second cleaning operation is the same as that shown in FIG.

First, the recording job command is received in S301, and it is determined whether or not the current job interval Tn from the end of the previous recording job to the reception of the recording job command is equal to or less than the second threshold value. If it is equal to or less than the second threshold value, 1 is added to the number of short-time recording jobs Mc in S302 to update (Mc = Mc + 1). If the current job interval Tn is larger than the second threshold value in S301, the process proceeds to S303.

S303 to S305 perform the same control as S101 to S103 shown in FIG. 5 of the first embodiment. After that, in S306, it is determined whether or not the cumulative number of recorded jobs M exceeds the threshold value Mth. The cumulative number of recorded jobs M is the number of jobs received in the past, and by comparing with the threshold value Mth, it is determined whether or not the number of samples that can statistically determine the usage tendency of the user has been reached. If the cumulative number of recorded jobs M does not exceed the threshold value Mth in S307, the usage tendency of the user cannot be statistically determined, so that the second cleaning operation is executed in S310. After that, the waiting time is reset to 0 and the sequence ends.

On the other hand, if the cumulative number of recorded jobs M exceeds the threshold value Mth in S307, whether or not the ratio (Mc / M) of the number of short-time recording jobs Mc to the cumulative number of recorded jobs M exceeds the threshold value P in S308. To judge. If Mc / M is larger than the threshold value P, it is judged that the user's usage tendency is that the job interval is short, that is, there is a high probability that the next recording job instruction will be received shortly after the end of the current recording job, and the first cleaning is performed in S308. Perform the action. After that, it is determined whether or not the waiting time during which the counting was continued in S309 is equal to or greater than the second threshold value. When the waiting time exceeds the second threshold value, the second cleaning operation is executed in S310 to reset the waiting time to 0, and the sequence ends.

On the contrary, when Mc / M is smaller than the threshold value P, the usage tendency of the user is that the job interval is long, that is, the time from the end of the current recording job to the reception of the next recording job instruction is equal to or greater than the second threshold value. Judge. Therefore, the second cleaning operation is executed in S310 without executing the first cleaning operation, the waiting time is reset to 0, and the sequence is ended.

As described above, by controlling the cleaning operation based on the ratio of the job interval shorter than the second threshold value with the second threshold value as a reference, the cleaning operation more suitable for the user's usage tendency can be selected. Can be done. When calculating the average value of the job intervals as shown in the second embodiment, for example, when the first job interval is 1 minute and the second job interval is 1 month, an appropriate average value cannot be calculated. There is. On the other hand, by calculating the ratio of the number of recorded jobs, which had a shorter job interval than the reference value, to the total number of recorded jobs as in the present embodiment, it is possible to execute a more appropriate cleaning operation. it can. In the present embodiment, the second threshold value is used as a reference, but the cleaning operation may be controlled by setting another reference value.

10 Inkjet recording device 120 Discharge port surface 110 Recording head 24 Wiper (cleaning means)
23 Cap (cleaning means)
4000 control circuit (control means)
4004 Non-volatile memory (storage means)

Claims (11)

Receiving means for receiving record job instructions and
A recording head having an ejection port surface provided with a plurality of ejection ports for ejecting ink and performing a recording operation based on a recording job command received by the receiving means.
A cleaning means for cleaning the discharge port surface and
When the waiting time during which the recording operation by the recording head is not performed has passed the first threshold value since the recording operation based on the previous recording job instruction is completed, the cleaning means is made to perform the first cleaning operation, and the standby is performed. and control means for time to perform the second cleaning operation in the cleaning unit and passes the first threshold larger than the second threshold value,
Comprising storage means for storing the job interval from the recording operation based on the recording job instructions past the ends until it receives the next printing job instruction of the recording job instructions, and
When the waiting time is less than the second threshold value and the job interval is equal to or greater than a predetermined value, the control means does not perform the first cleaning operation on the cleaning means and performs the second cleaning operation. An inkjet recording device characterized in that it is performed. The inkjet recording apparatus according to claim 1, wherein the predetermined value is equal to the second threshold value. When the waiting time is less than the second threshold value and the average value of the job intervals is equal to or more than a predetermined value, the control means does not perform the first cleaning operation on the cleaning means and the second cleaning means. The inkjet recording apparatus according to claim 1 or 2, wherein a cleaning operation is performed. When the waiting time is less than the second threshold value and the ratio of the number of jobs whose job interval is shorter than the predetermined time to the cumulative number of jobs in the past predetermined period is larger than the predetermined ratio, the control means is said to be the cleaning means. The inkjet recording apparatus according to claim 1 or 2, wherein the second cleaning operation is performed without performing the first cleaning operation. When the waiting time is less than the second threshold value and the cumulative number of jobs exceeds a predetermined threshold value and the ratio is larger than the predetermined ratio, the control means supplies the cleaning means to the first. The inkjet recording apparatus according to claim 4, wherein the second cleaning operation is performed without performing the cleaning operation. The cleaning means includes a wiper that performs a wiping operation that wipes the discharge port surface, a cap that performs a capping operation that covers the discharge port surface, and a pump that is connected to the cap and discharges ink from the cap. , the cleaning unit is the cap by driving the first and the intake引動operation, the first of said pump over from the long intake引動operation for discharging the ink accumulated within the cap by driving the pump an ink jet recording apparatus according to claim 1, any one of 5 to ink and the second intake引動operation for discharging the accumulated, and performs to within. In the first cleaning operation, when the number of times ink is ejected from the plurality of ejection ports is equal to or greater than a predetermined number of times, the wiper performs the wiping operation and the recording head ejects ink that does not contribute to the recording operation. The inkjet recording apparatus according to claim 6, wherein the cap performs the capping operation after the operation. In the first cleaning operation, when said amount of ink discharged by the preliminary discharge operation is equal to or greater than a predetermined amount, after the cleaning means has performed said first intake引動operation, said cap perform the capping operation The inkjet recording apparatus according to claim 7. If the wiper at the first cleaning operation is performed the wiping operation, to claim 7 or 8 wherein the second of said cleaning means in cleaning operation and performing the second intake引動work The inkjet recording apparatus described. When the wiper does not perform the wiping operation in the first cleaning operation, the wiper performs the wiping operation in the second cleaning operation, the recording head performs the preliminary discharge operation, and then the wiper performs the preliminary discharge operation. cleaning means ink jet recording apparatus according to any one of claims 7 to 9, the second intake引動the cap performs operation to and performing the capping operation. A recording head having an ejection port surface provided with a plurality of ejection ports for ejecting ink,
A cleaning method for an inkjet recording device including a cleaning means for cleaning the discharge port surface.
The receiving process for receiving record job instructions and
A recording process in which a recording operation is performed by the recording head based on a recording job instruction received in the receiving process, and a recording process.
When the waiting time during which the recording operation by the recording head is not performed has passed the first threshold value since the recording operation based on the previous recording job command is completed, the cleaning means performs the first cleaning operation, and the waiting time There a cleaning step of performing a second cleaning operation by the cleaning means and passes said first threshold value larger than the second threshold value,
In the cleaning step, the job interval from when the waiting time is less than the second threshold value and the recording operation based on the past recording job instruction is completed until the next recording job instruction of the recording job instruction is received. Is a predetermined value or more, a cleaning method for an inkjet recording apparatus, characterized in that the cleaning means does not perform the first cleaning operation but performs the second cleaning operation.

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