JP2018020446A - Ink jet recording device and cleaning method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform suitable cleaning operation according to an interval of performance of recording operation.SOLUTION: In ink jet recording device comprises: a recording head which has reception means which receives a recording job command, and a discharge port surface on which plural discharge ports for discharging an ink are provided, and performs recording operation based on the recording job command received by the reception means; cleaning means for cleaning the discharge port surface; and control means which causes the cleaning means to perform first cleaning operation when a standby time, during which recording operation by the recording head is not performed, has lapsed a first threshold from termination of recording operation based on a previous recording job command, and causes the cleaning means to perform second cleaning operation when the standby time has lapsed a second threshold larger than the first threshold. The control means causes the cleaning means not to perform first cleaning operation, but to perform second cleaning operation when the standby time is less than the second threshold and a job interval between the past recording jobs is equal to or more than a prescribed value.SELECTED DRAWING: Figure 5

Description

  The present invention relates to an ink jet recording apparatus that records an image by discharging ink from a recording head and a cleaning method thereof.

  In the ink jet recording apparatus disclosed in Patent Document 1, ink attached to the recording head is removed by wiping the ink discharge surface of the recording head after the recording operation is completed. In addition, after wiping, the pump is driven with the cap for covering the ink ejection surface of the recording head removed, so that the ink is sucked from the cap and the tube connected to the cap, so-called idle suction is performed. When the idle suction is completed, capping is performed to cover the ink discharge surface with a cap, so that it is possible to prevent an ink discharge failure that occurs when the ink discharge surface is dried and the ink is fixed.

JP 2015-36223 A

  However, in the configuration of Patent Document 1, since wiping, idle suction, and capping are performed every time the recording operation is completed, when the next recording operation is to be performed soon after the previous recording operation is completed, the next recording operation is performed. May cause the user to wait before starting.

  In view of such circumstances, an object of the present invention is to provide an ink jet recording apparatus that performs an appropriate cleaning operation in accordance with 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 print job command and an ejection port surface provided with a plurality of ejection ports for ejecting ink. A recording head that performs a recording operation based on the recording head, a cleaning unit that cleans the ejection port surface, and a standby time during which the recording operation by the recording head is not performed after the recording operation based on the previous recording job command is completed. The first cleaning operation is performed by the cleaning unit when the first threshold value has elapsed, and the second cleaning operation is performed by the cleaning unit when the second threshold value that is greater than the first threshold value has elapsed. An ink jet recording apparatus comprising: a control means; and after the recording operation based on a past recording job command is completed, Storage means for storing a job interval until the next recording job instruction is received after the instruction, and the control means is configured such that when the waiting time is less than the second threshold and the job interval is equal to or greater than a predetermined value. The cleaning means does not perform the first cleaning operation but performs the second cleaning operation.

  According to the present invention, there is provided an ink jet recording apparatus that performs an appropriate cleaning operation in accordance with an interval at which a recording operation is performed.

1 is a schematic diagram illustrating an ink jet recording apparatus according to a first embodiment. FIG. 3 is a diagram illustrating a recording head unit according to the first 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 structure which concerns on 1st Embodiment. It is a flowchart which shows control of the cleaning operation which concerns on 1st Embodiment. 6 is a flowchart showing control of a first cleaning operation and a second cleaning operation according to the first embodiment. It is a flowchart which shows control of the cleaning operation | movement which concerns on 2nd Embodiment. It is a flowchart which shows control of the cleaning operation which concerns on 3rd Embodiment.

  An embodiment of an ink jet 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 this specification, a serial type ink jet recording apparatus that performs recording by reciprocally moving a head that ejects ink to a recording medium that is intermittently transported in a direction that intersects the transport direction of the recording medium is taken as an example. explain. However, the present invention can be applied not only to a serial type ink jet recording apparatus but also to a line type ink jet recording apparatus that performs continuous printing using a long print head. In this specification, “ink” is used as a general term for a liquid such as a recording liquid. Furthermore, in this specification, “recording” includes not only recording on a flat object but also recording on a three-dimensional object. In the present specification, the “nozzle” is a generic term for an ejection port or a liquid path communicating with the ejection port and an element that generates energy used for ink ejection. In this specification, the “recording medium” is a generic term for recording media such as paper, cloth, plastic film, metal plate, glass, ceramics, wood, leather, etc., from which liquid is ejected. Further, the recording medium is not limited to cut paper but also includes roll-shaped continuous paper.

[First Embodiment]
FIG. 1 is a schematic diagram showing an ink jet recording apparatus (hereinafter, recording apparatus) 10 according to the present embodiment. The recording apparatus 10 mainly includes a recording head unit 100, a carriage 40, a paper feed unit (not shown), and a purge unit 20. The carriage 40 is supported by a support rail 60 and the like, and is mounted with the recording head unit 100 to reciprocate in the X direction (main scanning direction) shown in FIG.

  A paper feed tray 50 is provided on the bottom surface of the recording apparatus 10 and holds a recording medium used for recording. The recording medium loaded on the paper feed tray 50 is fed into the recording apparatus 10 by the paper feed unit. The fed recording medium is conveyed in the Y direction (conveyance direction) shown in FIG. A platen 19 is disposed at a position facing the recording head 110 on the downstream side of the conveying 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 the conveying roller 8 or the like (intermittent conveyance). By repeating the image formation for one band and the intermittent conveyance operation, an image is formed on the entire recording medium. In this specification, “recording operation” refers to a series of operations from when a recording medium is fed into the recording apparatus 10 to form an image and then ejected outside the recording apparatus 10.

  FIG. 2 is an enlarged view showing details of the recording head unit 100. 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 the present 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. In this embodiment, four colors of ink are used, but the present invention is not limited to this. For example, an ink using three or less colors may be used, or an ink using four or more colors may be added by adding other colors. Examples of the other color ink include gray ink, pigment black ink, and light cyan ink.

  As shown in FIG. 2B, the ejection port surface 120 of the recording head 110 is provided with an ejection port array in which ejection ports for ejecting ink are arranged for each color. The discharge port surface 120 is provided with two types, a black discharge port surface 120Bk having a black discharge port row and a color discharge port surface 120Cl having a remaining three color discharge port row. 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 details of the purge unit 20. The purge unit 20 is provided inside the moving area of the carriage 40 and outside the area where recording is performed on the recording medium (recording area). 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 (capping) or separate from the ejection 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 together. When the cap 23 including the black cap 23Bk and the color cap 23Cl is integrally moved vertically upward, 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 disposed on the tube 21. The tube pump 22 is provided with a rotating body (not shown). By rotating the rotating body, the tube 21 can be pushed and pressed to generate a negative pressure inside the tube 21. When the tube pump 22 is driven with the cap 23 capping the ejection port surface 120, the inside of the cap 23 can be set to a negative pressure and ink can be sucked from the ejection port. The sucked ink is discharged through a tube 21 to a waste ink absorber (discharge unit) (not shown). By sucking and discharging the air bubbles and the thickened ink mixed in the ink as described above, the ink discharge state of the recording head 110 can be maintained well.

  Further, the preliminary ejection operation of the recording head 110 is performed in a state where the cap 23 is separated from the ejection port surface 120 at a position facing the ejection port surface 120. The preliminary ejection operation means that ink that does not contribute to the recording operation is ejected from the recording head 110 and the thickened ink or the like is discharged. The preliminary ejection 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 preliminarily ejected to the cap 23 by the preliminarily ejecting operation, an empty suction operation for sucking the ink preliminarily ejected into the cap 23 by driving the tube pump 22 is performed. Thereby, the ink accumulated in the cap 23 is discharged.

  A wiper 24 is provided adjacent to the cap 23. The wiper 24 includes a base wiper 24 a that wipes the base substrate 130 and a nozzle wiper 24 b that wipes the discharge port (nozzle) surface 120. The wiper 24 moves in the direction a shown in FIG. 3 by a driving source (not shown) at a position where the discharge port surface 120 faces the cap 23, thereby wiping (wiping) the discharge port surface 120 and the base substrate 130. To do. When the wiping operation is completed, after the carriage 40 is retracted from the position facing the cap 23, the wiper 24 moves in the opposite direction 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, setting values for control, and the like. The RAM 4002 is used for data expansion when executing a control program, storage of print data and control commands, storage of control variables in each control, and the like. The timer circuit 4003 is a circuit that can acquire information on the current time or a circuit that can measure elapsed time. The nonvolatile memory 4004 can store parameters and the like used in the control even when the power of the main body is turned off. In the control according to the present embodiment, the nonvolatile memory 4004 can write and read the time that is the starting point for calculating the standby time. Used. The control circuit 4000 executes a control program stored in the ROM 4001 or a control program developed in the RAM 4002. The sequence executed in the present 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 an interface and a control signal when performing wired or wireless communication between the recording apparatus 10 main body and an external host device. The recording apparatus 10 receives a recording job command from an external host device via the external connection circuit 4005. The recording job command includes image data to be recorded. When receiving the recording job command, the recording apparatus 10 performs a recording operation on the above-described recording medium based on the image data. A series of operations from receiving a recording job command to discharging the recording medium out of the recording apparatus 10 by a recording operation is called a “recording job”. A recording job is also performed when a recording operation is performed on a plurality of recording media based on a single recording job command. Further, the current time may be input to the recording apparatus 10 via the external connection circuit 4005.

  The control circuit 4000 develops the received image data in the RAM 4002. Further, the control circuit 4000 controls the driving of the recording head unit 100 via the recording head unit driving 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 the recording operation once by the control circuit 4000, ink is ejected from the recording head 110 to a desired position on the recording medium while the carriage 40 is moving, and an image for one band is formed on the recording medium. The control circuit 4000 intermittently conveys the recording medium by controlling the conveyance motor 4013 via the conveyance 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 for sucking a predetermined amount of ink from the recording head 110. Under the control of the purge motor 4009, the capping operation of the discharge port surface 120 by the cap 23 and the wiping operation of the discharge port surface 120 by the wiper 24 are also performed. The control circuit 4000 performs a preliminary ejection operation by controlling the driving of the recording head unit 100 via the recording head unit driving circuit 4006. The pattern for driving the recording head 110 in this case is based on any of 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 illustrating control related to 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 idle suction operation, a preliminary discharge operation, and a capping operation. In the present embodiment, these cleaning operations are performed based on a job interval T that indicates the time from the end of the previous recording operation based on the recording job command to the reception of the previous recording job command. In other words, based on the job interval T between the previous recording job and the previous recording job, the cleaning operation performed during the waiting time after the end of the current recording job is controlled. Here, the waiting time is a time for starting counting after the recording job is completed, and indicates a time in which the recording apparatus 10 is waiting until the next recording job command is received. FIG. 5 is a flowchart showing the process from the reception of the recording job command to the end of the cleaning operation with the capping operation.

  First, when a recording job command is received from an external host device, a recording operation sequence is executed in S101. Along with the end of the recording operation, the standby time is reset in S102, and counting starts from zero. In S103, it is determined whether the standby time is equal to or greater than a first threshold value. If the standby time is less than the first threshold, the standby time is continuously counted. If the standby time is greater than or equal to the first threshold, it is determined in S104 whether the job interval T is greater than or equal to the second threshold (predetermined value). The second threshold is larger than the first threshold. In the present embodiment, the first threshold is 1 minute and the second threshold is 10 minutes.

  If the job interval T is greater than or equal to the second threshold value in S104, the process proceeds to S107 without performing the first cleaning operation, and the second cleaning operation is executed and the process ends. On the other hand, if 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 standby time during which the counting has been continued is equal to or greater than the second threshold value. If the standby time is less than the second threshold, the standby time is continuously counted. If the standby time has passed the second threshold, the second cleaning operation is executed in S107 and the sequence is terminated. Although the job interval T is compared with the second threshold value in S104, the present invention is not limited to this and may be compared with a threshold value different from the second threshold value.

  FIG. 6 is a flowchart for explaining 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 greater than a threshold value N2. The dot count value N is obtained by calculating the number of times ink is ejected from the ejection port of the recording head 110. The larger the dot count value N, the more fine ink mist that is scattered when ink is ejected by the recording operation is applied to the ejection port surface 120. The possibility of adhesion increases. In order to prevent ink discharge failure or the like due to the attached ink mist, when the dot count value N exceeds a threshold value N2 (predetermined number of times), a wiping operation is performed on the discharge port surface 120 to set the dot count value N to 0. Reset to. In this embodiment, the threshold value N2 for the black ejection port is 3.5 × 10 ^ 7 dots, the threshold value N2 for the color ejection port is 5.5 × 10 ^ 7 dots, and the threshold values for the black ink and the color ink, 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, if the dot count value N is larger than the threshold value N2 in S110, a wiping operation is performed in S111, and a preliminary ejection operation is performed in S112. The preliminary ejection operation performed here is performed in order to suppress the occurrence of ink color mixing due to ink being pressed against the ejection port by the wiping operation. When the preliminary ejection operation is completed, the process proceeds to S113.

  In S113, it is determined whether or not the ink amount (preliminarily ejected ink amount) W that has been preliminarily ejected in the preliminary ejection operations so far is greater than the threshold value W1 (predetermined amount). Since the ink preliminarily ejected in the preliminary ejection operation is received by the cap 23, when the ink amount exceeding the threshold W1 is preliminarily ejected, the ink is accumulated in the cap 23, and the ink is collected on the ejection port surface 120 by capping. May adhere. Therefore, when the preliminary discharge ink amount W exceeds the threshold value W1 in S113, the first idle suction operation for sucking the volume of the cap 23 is performed. When the first idle suction operation is performed, the count of the preliminary ejection ink amount W is subtracted by a predetermined amount. This is for the purpose of sucking and discharging the ink remaining in the cap 23 in the first suction, 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 preliminary ejection ink amount W is reset to 0 by a second idle suction operation described later.

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

  In S115, a capping operation is performed, and the sequence of the first cleaning operation is completed. In S110, it is determined whether or not the wiping operation is performed according to the dot count value. However, the configuration is not limited to this, and the wiping operation is performed according to the recording duty of the pattern recorded on the recording medium. Also good.

  The first cleaning operation described above is an operation for performing capping by performing a minimum necessary cleaning operation to prevent the discharge port surface 120 from drying. Therefore, by performing the second cleaning operation after the first cleaning operation, all of the wiping operation, idle suction operation, preliminary discharge operation, and capping operation are 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 as determined 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.

  Since the first cleaning operation is performed when the job interval T is less than the second threshold value (10 minutes), the next recording operation is started for a user having a short recording job command interval (job interval). The waiting time required until is shortened. For this reason, throughput is improved when a continuous recording operation is performed, and the user's feeling of use is also improved.

  Further, since the volume in the cap 23 is sucked and discharged in the first idle suction operation in S114, effects such as shortening the time required for the idle suction operation and improving the durability of the tube pump 22 can be obtained. In the present embodiment, the comparison between the preliminary discharge ink amount W and the threshold value W1 is performed only once in S113. However, the present invention is not limited to this, and determination is performed a plurality of times by providing a plurality of threshold values. The idle suction operation may be performed with a plurality of types of intensities by changing the driving time or the like.

  FIG. 6B shows the second cleaning operation, which is executed in S107 in the flowchart of FIG. First, in S120, it is determined 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 idle suction operation is performed in S126. Here, unlike the first idle suction operation, the second idle suction operation sucks and discharges ink remaining not only in the cap 23 but also in the tube 21. Therefore, suction is performed by driving the tube pump 22 for a longer time than the first idle suction operation. The second idle suction operation performed in S126 is performed with the capping performed in the first cleaning operation. Thereby, the time for moving the cap 23 in the vertical direction can be omitted, and drying of the discharge port surface 120 can be prevented. When the second idle suction operation is performed, the preliminary ejection ink amount W is reset to 0, and the sequence ends.

  On the other hand, if the wiping operation is not performed in the first cleaning operation, it is determined in S121 whether the cap 23 is in an open state, that is, whether the cap 23 is separated from the discharge port surface 120. If the cap 23 is not in the open state, that is, if it is in the capping state, the cap is opened in S122. On the other hand, if the cap 23 is open, 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. Thereafter, a second idle suction operation is performed in S125. Here, the second idle suction operation in S125 has the same purpose as the second idle suction operation in S126, but is different in that it is performed in the cap open state. In S125, the second empty suction operation is performed while the cap is open, so that the ink in the cap 23 is sucked before the capping operation even if the ink is accumulated in the cap 23 by the preliminary ejection operation performed in S124. Can be discharged. For this reason, it is possible to suppress ink ejection failure caused by the ink accumulated in the cap 23 adhering to the ejection port surface 120. When the second idle suction operation is performed, the preliminary ejection ink amount W is reset to 0, the capping operation is performed in S127, and the sequence is terminated. When the second cleaning operation ends, the standby time is reset to zero.

  The second cleaning operation described above is performed when a recording job command is not received for a predetermined time after the first cleaning operation is performed. Specifically, it is performed when the standby time exceeds the second threshold (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. In addition, since wasteful preliminary discharge operation can be omitted, the waste liquid of ink can be reduced. In this embodiment, the capping operation is performed after the first idle suction operation or the second idle suction operation. However, the present invention is not limited to this, and the cap 23 remains in the capping state after the capping operation. It is good also as a structure which performs idle suction operation and 2nd idle suction operation.

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

  Note that the job interval T in the present embodiment uses the job interval between the previous recording job and the previous recording job, but is not limited thereto, and may be any job interval between successive 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 one job interval. However, in the present embodiment, the control is performed based on an average job interval Ta obtained by averaging past job intervals. The basic configuration is the same as in the first embodiment, and the fish in the first cleaning operation and the second cleaning operation is the same as that shown in FIG.

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

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

  As described above, by controlling the cleaning operation to be executed based on the average job interval Ta, in addition to the effects obtained in the first embodiment, it is possible to execute a cleaning operation more suitable for the user's usage. In calculating the average job interval Ta, 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 this embodiment, when the second threshold is used as a reference, it is first determined whether the job interval is longer or shorter than the second threshold, and the job interval is shorter than the second threshold. The cleaning operation is controlled based on whether or not the number of jobs is larger than the threshold value P. That is, the control is performed based on whether the ratio of the short-time recording job number Mc whose job interval is shorter than the second threshold to the past cumulative job number is a predetermined value or more. Further, these controls are performed after the cumulative recording job number M, which is the number of jobs received in the past, exceeds a predetermined threshold Mth. The cumulative recording job number M may be the total number of recording jobs so far or the cumulative number of recording jobs in a predetermined period. That is, after performing the recording operation for the number of recording jobs that can statistically determine the user's usage tendency, the cleaning operation to be executed is selected. The control related to the cleaning operation of the present embodiment will be specifically described with reference to FIG. The basic configuration is the same as in 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, a 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 smaller than a second threshold value. If it is equal to or smaller than the second threshold value, 1 is added to the short-time recording job number Mc and updated in S302 (Mc = Mc + 1). If the current job interval Tn is larger than the second threshold in S301, the process proceeds to S303.

  From S303 to S305, the same control as S101 to S103 shown in FIG. 5 of the first embodiment is performed. Thereafter, in S306, it is determined whether or not the cumulative recording job number M exceeds the threshold value Mth. The cumulative recording job number 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 recording job number M does not exceed the threshold value Mth in S307, the user's usage tendency cannot be determined statistically, and therefore the second cleaning operation is executed in S310. Thereafter, the standby time is reset to 0 and the sequence is terminated.

  On the other hand, if the cumulative recording job number M exceeds the threshold Mth in S307, whether or not the ratio (Mc / M) of the short-time recording job number Mc to the cumulative recording job number M exceeds the threshold P in S308. Determine whether. If Mc / M is larger than the threshold value P, it is determined that the user's usage tendency is that the job interval is short, that is, there is a high probability of receiving the next recording job command soon after the end of the current recording job, and the first cleaning is performed in S308. Perform the action. Thereafter, in S309, it is determined whether or not the standby time for which counting has been continued is equal to or greater than the second threshold value. If the standby time exceeds the second threshold value, the second cleaning operation is executed in S310 to reset the standby time to 0, and the sequence ends.

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

  As described above, the cleaning operation is controlled based on the ratio of the job interval shorter than the second threshold on the basis of the second threshold, thereby selecting a cleaning operation more suitable for the user's usage tendency. Can do. When calculating the average value of job intervals as shown in the second embodiment, for example, when the first job interval is 1 minute and the second job interval is one month, an appropriate average value cannot be calculated. There is. On the other hand, a more appropriate cleaning operation can be executed by calculating the ratio of the number of recording jobs that have a shorter job interval than the reference value to the total number of recording jobs as in this embodiment. it can. In the present embodiment, the second threshold is used as a reference. However, the present invention is not limited to this, and another reference value may be provided to control the cleaning operation.

DESCRIPTION OF SYMBOLS 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 a recording job command;
A recording head having a discharge port surface provided with a plurality of discharge ports for discharging ink, and performing a recording operation based on a recording job command received by the receiving unit;
Cleaning means for cleaning the discharge port surface;
When the standby time during which the recording operation by the recording head is not performed after the recording operation based on the previous recording job command has passed the first threshold, the cleaning unit performs the first cleaning operation, and the standby A control unit that causes the cleaning unit to perform a second cleaning operation when time elapses over the second threshold value that is greater than the first threshold value,
Storage means for storing a job interval from when a recording operation based on a past recording job instruction is completed until the recording job instruction next to the recording job instruction is received;
When the waiting time is less than the second threshold and the job interval is greater than or equal to a predetermined value, the control unit does not perform the first cleaning operation on the cleaning unit and performs the second cleaning operation. An ink jet recording apparatus, wherein   The inkjet recording apparatus according to claim 1, wherein the predetermined value is equal to the second threshold value.   The control unit does not perform the first cleaning operation on the cleaning unit when the waiting time is less than the second threshold and the average value of the job intervals is equal to or greater than a predetermined value. The inkjet recording apparatus according to claim 1, wherein a cleaning operation is performed.   When the waiting time is less than the second threshold and the ratio of the number of jobs with the job interval shorter than the predetermined time to the cumulative number of jobs in the past predetermined period is larger than the predetermined ratio, the cleaning unit 3. The ink jet recording apparatus according to claim 1, wherein the second cleaning operation is performed without performing the first cleaning operation.   When the waiting time is less than the second threshold and the cumulative job number exceeds a predetermined threshold, and the ratio is greater than a predetermined ratio, the control unit causes the cleaning unit to The inkjet recording apparatus according to claim 4, wherein the second cleaning operation is performed without performing a cleaning operation.   The cleaning unit includes a wiper that performs a wiping operation for wiping the discharge port surface, a cap that performs a capping operation to cover the discharge port surface, and a pump that is connected to the cap and discharges ink from the cap. The cleaning means drives the pump to discharge ink accumulated in the cap, and drives the pump for a longer time than the first idle suction operation to drive the cap. 6. The ink jet recording apparatus according to claim 1, wherein a second idle suction operation for discharging the ink accumulated in the inside is performed.   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, 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 performing the operation.   In the first cleaning operation, when the amount of ink ejected by the preliminary ejection operation is equal to or greater than a predetermined amount, the cap performs the capping operation after the cleaning unit performs the first idle suction operation. The ink jet recording apparatus according to claim 6 or 7.   9. The method according to claim 6, wherein when the wiper performs the wiping operation in the first cleaning operation, the cleaning unit performs the second idle suction operation in the second cleaning operation. The ink jet recording apparatus according to any one of the above.   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, and after the recording head performs the preliminary ejection operation, The inkjet recording apparatus according to claim 6, wherein a cleaning unit performs the second idle suction operation and the cap performs the capping operation. A recording head having a discharge port surface provided with a plurality of discharge ports for discharging ink;
A cleaning means for cleaning the discharge port surface, and a cleaning method for an inkjet recording apparatus comprising:
A receiving step for receiving a recording job instruction;
A recording step of performing a recording operation with the recording head based on the recording job command received in the receiving step;
When the standby time when the recording operation by the recording head is not performed after the recording operation based on the previous recording job command has passed the first threshold, the cleaning unit performs the first cleaning operation, and the standby time Has a cleaning step of performing a second cleaning operation by the cleaning means when the second threshold value is greater than the first threshold value,
In the cleaning step, the waiting time is less than the second threshold value, and the job interval from when 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 When the ink is equal to or greater than a predetermined value, the cleaning means performs the second cleaning operation without performing the first cleaning operation.

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