Recording device, control method for recording device, program

Abstract

To solve a problem in which there is a possibility that a function of a blade cannot be maintained because of poor slipperiness between a conveyance belt and the blade and resulting damage in the blade that is brought into contact with the conveyance belt.SOLUTION: A liquid discharge device includes a liquid discharge part for discharging a liquid to a medium, a conveyance belt which is opposite to the liquid discharge part and conveys the medium, a cleaning member which cleans the conveyance belt by being brought into contact with the conveyance belt and can perform switching between a contact state where it is brought into contact with the conveyance belt and a separate state where it is separated from the conveyance belt, and a control part for controlling the liquid discharge operation by the liquid discharge part, the rotation operation of the conveyance belt, and the state switching of the cleaning member, wherein the control part performs preliminary discharge that preliminarily discharges the liquid to the conveyance belt from the liquid discharge part on the basis of the preliminarily set cleaning control information when the cleaning member performs cleaning operation for cleaning the conveyance belt.SELECTED DRAWING: Figure 5

Description

Technical Field

[0005] , , ,

[0004] ,

[0001] The present invention relates to a recording apparatus that records on a medium. The present invention also relates to a control method for the recording apparatus and a program.

Background Art

[0002] In a recording apparatus typified by a printer, a configuration for conveying a medium typified by a recording paper using a conveyance belt is known, and in such a configuration, a configuration for cleaning the ink adhered to the conveyance belt with a blade may be adopted. The blade described in Patent Document 1 is formed by coating urethane rubber with a fluororesin and is provided so as to be able to contact and separate from the conveyance belt.

Prior Art Document

Patent Document

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] For example, when ink is ejected in a state where there is no medium on the conveyance belt due to a jam of the medium, that is, when ink is erroneously ejected, ink landing portions and non-landing portions may occur on the conveyance belt, and even in the ink landing portions, the amount of landed ink may be small. Since the landing portion is a wet region, the slipperiness between the conveyance belt and the blade becomes good. On the other hand, in the non-landing portion or even in the landing portion where the amount of ink is small, the slipperiness between the conveyance belt and the blade deteriorates. If the slipperiness between the conveyance belt and the blade is poor, the blade in contact with the conveyance belt may be damaged, and there is a risk that the function of the blade cannot be maintained.

Means for Solving the Problems

[0005] To solve the above problems, the present invention provides a recording device comprising: a liquid discharge unit for discharging liquid onto a medium; a conveyor belt facing the liquid discharge unit and transporting the medium; a cleaning member for cleaning the conveyor belt by contacting the conveyor belt, the cleaning member being able to switch between a contact state in contact with the conveyor belt and a separated state in separation from the conveyor belt; and a control unit that controls the liquid discharge operation by the liquid discharge unit, the rotation operation of the conveyor belt, and the state switching of the cleaning member, wherein the control unit, when performing a cleaning operation to clean the conveyor belt with the cleaning member, performs a preliminary discharge in which liquid is discharged from the liquid discharge unit onto the conveyor belt in advance based on preset cleaning control information.

[0006] Furthermore, the control method for a liquid dispensing device of the present invention comprises a liquid dispensing unit for dispensing liquid into a medium, a conveyor belt facing the liquid dispensing unit for conveying the medium, and a cleaning member for cleaning the conveyor belt by contacting the conveyor belt, the cleaning member being able to switch between a contact state in which it is in contact with the conveyor belt and a separated state in which it is separated from the conveyor belt, characterized in that when the conveyor belt is cleaned by the cleaning member, a preliminary dispensing is performed in which liquid is discharged from the liquid dispensing unit onto the conveyor belt in advance.

[0007] Furthermore, the present invention is a program executed by a control unit of a liquid dispensing device comprising: a liquid dispensing unit for dispensing liquid onto a medium; a conveyor belt facing the liquid dispensing unit and transporting the medium; and a cleaning member for cleaning the conveyor belt by contacting the conveyor belt, the cleaning member being capable of switching between a contact state in contact with the conveyor belt and a separated state in separation from the conveyor belt, and is characterized in that when the cleaning member cleans the conveyor belt, the program includes a step of performing a preliminary dispensing, in which liquid is discharged from the liquid dispensing unit onto the conveyor belt in advance. [Brief explanation of the drawing]

[0008] [Figure 1] A diagram showing the media transport path in a printer. [Figure 2] A block diagram showing the configuration and control system of the belt unit. [Figure 3] Side view of the conveyor belt, the first cleaning section, and the second cleaning section. [Figure 4] Side view of the conveyor belt, the first cleaning section, and the second cleaning section. [Figure 5] A flowchart illustrating the process of cleaning a belt using a blade. [Figure 6] This diagram shows an example of the ink ejection area when ink is accidentally ejected onto the conveyor belt. [Figure 7] A table showing an example of cleaning control information. [Figure 8] A table showing an example of cleaning control information. [Figure 9] A table showing an example of discharge volume adjustment information. [Figure 10] This diagram shows an example of the ink ejection area when ink is accidentally ejected onto the conveyor belt. [Modes for carrying out the invention]

[0009] The present invention will be described in general terms below. A recording device according to the first embodiment comprises: a liquid discharge unit for discharging liquid onto a medium; a conveyor belt facing the liquid discharge unit and for transporting the medium; a cleaning member for cleaning the conveyor belt by contacting the conveyor belt, the cleaning member being able to switch between a contact state in contact with the conveyor belt and a separated state in separation from the conveyor belt; and a control unit that controls the liquid discharge operation by the liquid discharge unit, the rotation operation of the conveyor belt, and the state switching of the cleaning member, wherein when the control unit performs a cleaning operation to clean the conveyor belt with the cleaning member, it performs a preliminary discharge in which it discharges liquid from the liquid discharge unit onto the conveyor belt in advance based on preset cleaning control information.

[0010] According to this embodiment, when the control unit performs a cleaning operation to clean the conveyor belt with the cleaning member, it performs a preliminary discharge of liquid from the liquid discharge unit to the conveyor belt based on preset cleaning control information. This preliminary discharge improves the sliding properties between the conveyor belt and the cleaning member, thereby maintaining the function of the cleaning member.

[0011] The second embodiment is characterized in that, in the first embodiment, the cleaning control information is set such that one or more of the discharge duty cycle, humidity, temperature, and elapsed time since the accidental discharge of liquid from the liquid discharge unit are used as the conditions for executing the preliminary discharge, and at least one of the following is set to act on the execution of the preliminary discharge: a first event in which the discharge duty cycle is lower than the first discharge duty cycle, a second event in which the humidity is lower than the first humidity, a third event in which the temperature is higher than the first temperature, and a fourth event in which the elapsed time is longer than the first elapsed time.

[0012] According to this embodiment, the cleaning control information is set such that at least one of the following events acts on the execution of the preliminary discharge: a first event in which the discharge duty cycle is lower than the first discharge duty cycle, a second event in which the humidity is lower than the first humidity, a third event in which the temperature is higher than the first temperature, and a fourth event in which the elapsed time is longer than the first elapsed time. Therefore, the preliminary discharge is performed appropriately according to the conditions when the cleaning operation is performed, and the function of the cleaning member can be maintained. Furthermore, if the preliminary discharge is unnecessary, it will not be performed, thus suppressing the wasteful consumption of liquid. Furthermore, the fact that each of the first, second, third, and fourth events affects the execution of the preliminary discharge does not mean that the preliminary discharge will necessarily be performed when each event occurs, but rather that the occurrence of each event works to the advantage of the execution of the preliminary discharge.

[0013] In the third aspect, in the second aspect, the cleaning control information sets the ejection duty and the humidity as the execution conditions for the preliminary ejection, and when the first event and the second event occur simultaneously, causes the control unit to execute the preliminary ejection, and when the first event and the second event do not occur simultaneously, is set such that the control unit does not execute the preliminary ejection.

[0014] If the first event occurs but the second event does not occur, the slipperiness between the conveyor belt and the cleaning member is likely to be ensured. Conversely, if the second event occurs but the first event does not occur, the slipperiness between the conveyor belt and the cleaning member is likely to be ensured. According to this aspect, in such a case, the preliminary ejection is not executed, so that wasteful consumption of the liquid can be suppressed.

[0015] In the fourth aspect, in any one of the first to third aspects, the control unit adjusts the liquid ejection amount when performing the preliminary ejection based on preset ejection amount adjustment information. According to this aspect, since the control unit adjusts the liquid ejection amount when performing the preliminary ejection based on preset ejection amount adjustment information, the liquid ejection amount when performing the preliminary ejection is made an appropriate amount, so that the slipperiness between the conveyor belt and the cleaning member becomes good, and wasteful consumption of the liquid can also be suppressed.

[0016] In the fifth aspect, in the fourth aspect, the ejection amount adjustment information includes one or more of the ejection duty, the humidity, the temperature, and the elapsed time as adjustment conditions for the liquid ejection amount, and at least one of a decrease in the ejection duty, a decrease in the humidity, an increase in the temperature, and an increase in the elapsed time is set to act on an increase in the liquid ejection amount in the preliminary ejection.

[0017] According to this aspect, one or more of the discharge duty, the humidity, the temperature, and the elapsed time are included as adjustment conditions for the liquid discharge amount, and at least one of a decrease in the discharge duty, a decrease in the humidity, an increase in the temperature, and an increase in the elapsed time is set to act on an increase in the liquid discharge amount in the preliminary discharge. Therefore, when the slipperiness between the conveyance belt and the cleaning member is low, the liquid discharge amount is increased, and the slipperiness between the conveyance belt and the cleaning member can be appropriately improved.

[0018] A sixth aspect is, in the fifth aspect, the discharge amount adjustment information includes the discharge duty as a determination condition for the liquid discharge amount, and the control unit calculates the discharge duty for each region partitioned along the width direction, which is a direction intersecting the traveling direction of the conveyance belt, and adjusts the liquid discharge amount for each region.

[0019] According to this aspect, the control unit calculates the discharge duty for each region partitioned along the width direction, which is a direction intersecting the traveling direction of the conveyance belt, and adjusts the liquid discharge amount for each region. Therefore, the liquid discharge amount is adjusted in a finer range, the slipperiness between the conveyance belt and the cleaning member becomes good, and wasteful consumption of the liquid can also be suppressed.

[0020] A seventh aspect is, in any one of the second to sixth aspects, the control unit performs the preliminary discharge so that the region preliminarily discharged contacts the cleaning member before the region where the liquid lands due to the mis-discharge on the conveyance belt.

[0021] According to this aspect, the control unit performs the preliminary discharge so that the region preliminarily discharged contacts the cleaning member before the region where the liquid lands due to the mis-discharge on the conveyance belt. Therefore, the cleaning member cleans the region where the mis-discharge occurs in a pre-wetted state, and the function of the cleaning member can be more reliably maintained.

[0022] The eighth embodiment is characterized in that, in any of the second to seventh embodiments, the control unit performs the preliminary discharge in such a manner that it avoids the portion of the conveyor belt where the liquid has landed due to the erroneous discharge. According to this embodiment, the control unit performs the preliminary discharge in such a way as to avoid the portion of the conveyor belt where the liquid has landed due to the misdischarge. As the preliminary discharge is performed while avoiding already wet portions, the wasteful consumption of liquid can be suppressed.

[0023] The ninth embodiment is characterized in that, in any of the second to seventh embodiments, when the control unit performs the preliminary discharge, it selects, based on preset discharge area setting information, a first discharge mode in which the liquid is discharged so as to avoid the portion of the conveyor belt where the liquid has landed due to the erroneous discharge, and a second discharge mode in which the liquid is discharged towards the portion of the conveyor belt where the liquid has landed and the portion where it has not landed.

[0024] According to this embodiment, when performing the preliminary discharge, the control unit selects a first discharge mode, based on preset discharge area setting information, which discharges liquid so as to avoid the area on the conveyor belt where liquid has landed due to the erroneous discharge, and a second discharge mode, which discharges liquid towards both the area on the conveyor belt where liquid has landed and the area where it has not. Therefore, the first discharge mode can suppress the amount of liquid consumed. In addition, in the second discharge mode, liquid is also discharged to the area on the conveyor belt where liquid has landed due to the erroneous discharge, which can soften the area where liquid has landed and improve the cleaning effect.

[0025] The tenth aspect is characterized in that, in the ninth aspect, the control unit is configured to select the first discharge mode when the humidity exceeds the reference humidity, and to select the second discharge mode when the humidity is equal to or less than the reference humidity. According to this embodiment, if the portion of the conveyor belt where liquid has landed due to accidental discharge has not yet dried sufficiently, the first discharge mode is selected, thereby suppressing liquid consumption. Furthermore, if the portion of the conveyor belt where liquid has landed due to accidental discharge has already dried sufficiently, the second discharge mode is selected, which softens the portion of the conveyor belt where liquid has landed due to accidental discharge, thereby enhancing the cleaning effect.

[0026] The eleventh embodiment is characterized in that, in any of the first to tenth embodiments, the control unit rotates the conveyor belt while maintaining the cleaning member in the separated state until the cleaning member faces the area on the conveyor belt where liquid has landed, and when the cleaning member faces the area on the conveyor belt where liquid has landed, the cleaning member switches from the separated state to the contact state.

[0027] According to this embodiment, the control unit rotates the conveyor belt while maintaining the cleaning member in the separated state until the cleaning member approaches the area on the conveyor belt where liquid has landed. When the cleaning member approaches the area on the conveyor belt where liquid has landed, the control unit switches the cleaning member from the separated state to the contact state. This reduces the period during which the cleaning member is in contact with areas on the conveyor belt where liquid has not landed, thereby more reliably maintaining the function of the cleaning member.

[0028] A control method according to the twelfth embodiment is a control method for a liquid dispensing device comprising: a liquid dispensing unit for dispensing liquid into a medium; a conveyor belt facing the liquid dispensing unit and for conveying the medium; and a cleaning member for cleaning the conveyor belt by contacting the conveyor belt, the cleaning member being able to switch between a contact state in which it is in contact with the conveyor belt and a separated state in which it is separated from the conveyor belt, characterized in that when the conveyor belt is cleaned by the cleaning member, a preliminary dispensing is performed in which liquid is discharged from the liquid dispensing unit onto the conveyor belt in advance.

[0029] According to this embodiment, when the cleaning member performs a cleaning operation to clean the conveyor belt, a preliminary discharge is performed in which liquid is discharged from the liquid discharge unit onto the conveyor belt in advance. This preliminary discharge improves the sliding properties between the conveyor belt and the cleaning member, thereby maintaining the function of the cleaning member.

[0030] A program according to the 13th embodiment is a program executed by a control unit of a liquid dispensing device comprising: a liquid dispensing unit for dispensing liquid onto a medium; a conveyor belt facing the liquid dispensing unit and transporting the medium; and a cleaning member for cleaning the conveyor belt by contacting the conveyor belt, the cleaning member being capable of switching between a contact state in contact with the conveyor belt and a separated state in separation from the conveyor belt, characterized in that when the conveyor belt is cleaned by the cleaning member, the program includes a step of pre-dispensing, in which liquid is discharged from the liquid dispensing unit onto the conveyor belt in advance.

[0031] According to this embodiment, when the cleaning member performs a cleaning operation to clean the conveyor belt, a preliminary discharge is performed in which liquid is discharged from the liquid discharge unit onto the conveyor belt in advance. This preliminary discharge improves the sliding properties between the conveyor belt and the cleaning member, thereby maintaining the function of the cleaning member.

[0032] The present invention will be described in detail below. In the following description, an inkjet printer 1, which records by ejecting a liquid such as ink onto a medium such as recording paper, will be described as an example of a recording device. Hereafter, the inkjet printer 1 will be abbreviated as printer 1.

[0033] The XYZ coordinate system shown in each figure is a Cartesian coordinate system, where the Y-axis direction is the width direction intersecting the medium transport direction, and also the depth direction of the device. Furthermore, within the Y-axis direction, the +Y direction is defined as the direction from the front to the back of the device, and the -Y direction is defined as the direction from the back to the front of the device. The X-axis direction is the width direction of the device, and from the perspective of the operator of printer 1, the direction in which the arrow points, +X, is to the left, and the opposite direction, -X, is to the right. The Z-axis direction is the vertical direction, i.e., the height direction of the device, and the direction in which the arrow points, +Z, is upward, and the opposite direction, -Z, is downward.

[0034] The G-axis direction is the normal direction to the ink ejection surface 26a of the line head 26, which will be described later. The F-axis direction is parallel to the ink ejection surface 26a and is the media transport direction at the position opposite the ink ejection surface 26a. The direction indicated by the arrow, +F, is the downstream transport direction, and the opposite direction, -F, is the upstream transport direction. In the following, the direction in which the media is transported will be referred to as "downstream," and the opposite direction will be referred to as "upstream." Additionally, some figures use the FGY coordinate system instead of the XYZ coordinate system.

[0035] In Figure 1, the media transport path is shown by a dashed line. In printer 1, the media is transported through the media transport path shown by the dashed line. The printer 1's main unit 2 includes a first media cassette 3 and a second media cassette 4 for storing media before feeding. The symbol P indicates the media stored in each media cassette. The first media cassette 3 and the second media cassette 4 are detachably attached to the main unit 2 from the front side of the device. The first media cassette 3 is provided with a pick roller 9 for ejecting the contained media, and the second media cassette 4 is provided with a pick roller 10 for ejecting the contained media.

[0036] Furthermore, the first media cassette 3 is provided with a pair of feed rollers 11 that feeds the dispensed media diagonally upward. The second media cassette 4 is provided with a pair of feed rollers 12 that feeds the dispensed media diagonally upward, and a pair of transport rollers 13 that transports the media upward. In the following, unless otherwise specified, a "roller pair" refers to a drive roller driven by a motor (not shown) and a driven roller that rotates in contact with the drive roller.

[0037] The media dispensed from each media cassette is conveyed to conveyor roller pair 16 by conveyor roller pair 14 and conveyor roller pair 15. The media receiving the feeding force from conveyor roller pair 16 is conveyed between the line head 26 and the conveyor belt 33, that is, to a position facing the line head 26.

[0038] The head unit 25 is equipped with a line head 26, which performs recording by ejecting ink, an example of a liquid, onto the surface of the medium. The line head 26 is an ink ejection head configured such that the nozzle (not shown) that ejects ink covers the entire area in the width direction of the medium, and is configured as an ink ejection head that can record across the entire width of the medium without movement in the width direction of the medium. The line head 26 is an example of a liquid ejection unit that ejects liquid. However, the ink ejection head may be of a type that performs recording while moving in the media width direction.

[0039] Reference numeral 5 denotes an ink storage section that contains ink. Ink discharged from the line head 26 is supplied from the ink storage section 5 to the line head 26 via a tube (not shown). The ink storage section 5 is composed of a plurality of ink tanks arranged along the X-axis.

[0040] The conveyor belt 33, the drive pulley 31, and the driven pulley 32 constitute the belt unit 30. The conveyor belt 33 is an endless belt that is wrapped around the drive pulley and the driven pulley 32. The conveyor belt 33 rotates when the drive pulley 31 is driven by the belt drive motor 57 (see Figure 2). The medium is transported to a position opposite the line head 26 while being attracted to the conveyor belt 33. The attraction of the medium to the conveyor belt 33 will be explained in more detail later.

[0041] Here, the media transport path passing opposite the line head 26 intersects both the horizontal and vertical directions, and is configured to transport the media diagonally upward. This diagonally upward transport direction includes the -X and +Z components in Figure 1, and this configuration allows the horizontal dimensions of the printer 1 to be suppressed. In this embodiment, the media transport path passing opposite the line head 26 is set to an inclination angle in the range of 50° to 70° with respect to the horizontal direction, and more specifically, to an inclination angle of 60°.

[0042] The medium on which the first surface has been recorded by the line head 26 is further propelled diagonally upward by the pair of conveyor rollers 17 located downstream of the conveyor belt 33. A flap 23 is provided downstream of the transport roller pair 17, and this flap 23 switches the transport direction of the medium. If the medium is to be discharged as is, the transport path of the medium is switched by the flap 23 to go towards the transport roller pair 20 above. A further flap 24 is provided downstream of the transport roller pair 20, and this flap 24 switches the transport path to either discharge from discharge position A1 or transport to the transport roller pair 21 located further vertically above. If the medium is sent towards the transport roller pair 21, it is discharged from discharge position A2. The medium discharged from discharge position A1 is received by a discharge tray 27 that is tilted diagonally upward, including components in the +X and +Z directions. The medium discharged from discharge position A2 is received by an optional tray (not shown).

[0043] When recording is to be performed on a second surface in addition to the first surface of the medium, the medium is conveyed by the flap 23 in an oblique upward direction including the -X direction component and the +Z direction component, passes through branching position K1, and is sent to an upward switchback path from branching position K1. A pair of transport rollers 22 is provided in this switchback path, and once the medium enters the switchback path, it is conveyed upward by the pair of transport rollers 22. When the upstream end of the medium passes branching position K1, the rotation direction of the pair of transport rollers 22 is switched, and the medium is conveyed downward.

[0044] The medium, conveyed downward by the conveyor roller pair 22, receives feeding force from the conveyor roller pair 18, the conveyor roller pair 19, and the conveyor roller pair 15, reaches the conveyor roller pair 16, and is then sent back to the conveyor belt 33 by the conveyor roller pair 16. The medium, once again sent to a position facing the line head 26, has its second side facing the line head 26, opposite to the first side which has already been recorded. This allows the line head 26 to record on the second side of the medium. The medium, with the second side recorded on it, is discharged from either the discharge position A1 or the discharge position A2 described above.

[0045] Next, the belt unit 30, the first cleaning unit 35, and the second cleaning unit 40 will be described with reference to Figures 3 and 4. The conveyor belt 33, which constitutes the belt unit 30, is an endless belt made of a base material such as urethane or rubber, with conductive material added as needed to adjust the resistance value, and is wrapped around the upstream drive pulley 31 and the downstream driven pulley 32. The conveyor belt 33 is subjected to a predetermined tension by a tensioner (not shown).

[0046] The drive pulley 31 is rotationally driven by a belt drive motor 57 (see Figure 2) controlled by a control unit 50 (see Figure 2). When the drive pulley 31 is rotationally driven in the direction of arrow a, the conveyor belt 33 rotates in the clockwise direction as shown in Figures 3 and 4. Hereafter, this rotation of the conveyor belt 33 may be referred to as "forward rotation". When the drive pulley 31 is rotated in the direction of arrow b, the conveyor belt 33 rotates counterclockwise in the direction shown in Figures 3 and 4. Hereafter, this rotation of the conveyor belt 33 may be referred to as "reverse rotation".

[0047] A charging roller 29 is provided at a position opposite the drive pulley 31, with the conveyor belt 33 in between. The charging roller 29 is in contact with the outer surface of the conveyor belt 33 and rotates in response to the rotation of the conveyor belt 33. A DC voltage is applied to the charging roller 29 by the belt charging unit 58 (see Figure 2), thereby supplying electric charge to the part of the charging roller 29 that is in contact with the conveyor belt 33. The belt charging unit 58 (see Figure 2) is controlled by the control unit 50, which switches the voltage application to the charging roller 29 on and off and switches the voltage applied to the charging roller 29.

[0048] In this embodiment, the charging roller 29 supplies a positive charge to the conveyor belt 33, causing the outer surface 33a of the conveyor belt 33 to be positively charged, thereby making the outer surface 33a of the conveyor belt 33 an adsorption surface that attracts the medium.

[0049] A support roller 34 that contacts the media is provided upstream of the line head 26. The support roller 34 presses the media against the portion of the conveyor belt 33 that is wrapped around the drive pulley 31. The support roller 34 is grounded, thereby removing any charge from the recording surface of the media.

[0050] Next, a first cleaning section 35 is provided near the driven pulley 32. The first cleaning section 35 includes a blade 36, which is an example of a cleaning member for cleaning the outer circumferential surface 33a of the conveyor belt 33. The blade 36 is fixed to a fixing member 37, and the fixing member 37 is rotatably mounted around a rotation axis 38.

[0051] The blade 36 is, for example, a plate-shaped elastic member having a predetermined thickness, made of urethane, rubber, or the like, and can be elastically deformed while in contact with the conveyor belt 33. The tip of the blade 36 comes into contact with the portion of the conveyor belt 33 that is wrapped around the driven pulley 32, thereby cleaning the outer surface 33a of the conveyor belt 33.

[0052] The rotating shaft 38 is rotated by the blade drive unit 59 (see Figure 2), and as the rotating shaft 38 rotates, the blade 36 switches between a contact state in which it is in contact with the conveyor belt 33 (see Figure 3) and a separated state in which it is separated from the conveyor belt 33 (see Figure 4). When the blade 36 is in contact, the conveyor belt 33 rotates in the forward direction, so any deposits such as ink and paper dust attached to the outer surface 33a of the conveyor belt 33 are removed. Furthermore, the blade drive unit 59 (see Figure 2) can be composed of an actuator such as a motor. The control unit 50 can also adjust the pressing force when the blade 36 presses against the conveyor belt 33 by adjusting the amount of rotation of the rotating shaft 38.

[0053] A second cleaning section 40 is provided below the first cleaning section 35. The second cleaning section 40 is equipped with a cleaning sheet 41. The cleaning sheet 41 is wrapped around the drive pulley 42 and the driven pulleys 43 and 44, and tension is applied to it by a tensioner 45.

[0054] In this embodiment, the cleaning sheet 41 is an endless piece of fabric that can be pressed against the outer surface 33a of the conveyor belt 33 by the driven pulley 43. The drive pulley 42 is rotationally driven by the sheet drive motor 61 (see Figure 2). The drive pulley 42 is rotationally driven in the clockwise direction in Figure 3, thereby causing the cleaning sheet 41 to rotate in the clockwise direction in Figure 3.

[0055] The second cleaning unit 40 is provided so as to be movable in a direction relative to the conveyor belt 33, specifically along the G-axis direction, and moves forward and backward relative to the conveyor belt 33 by receiving power from the unit drive unit 60 (see Figure 2). The unit drive unit 60 can be made up of an actuator such as a motor. When the second cleaning unit 40 moves forward relative to the conveyor belt 33, the cleaning sheet 41 is pressed against the conveyor belt 33 by the driven pulley 43. In this state, as the conveyor belt 33 rotates forward, the cleaning sheet 41 moves in a circular motion, wiping the outer surface 33a of the conveyor belt 33. Figures 3 and 4 show the second cleaning unit 40 in a retracted position relative to the conveyor belt 33, and the state in which the second cleaning unit 40 moves forward relative to the conveyor belt 33 is not shown.

[0056] The aforementioned belt drive motor 57, belt charging unit 58, blade drive unit 59, unit drive unit 60, and seat drive motor 61 are all controlled by a control unit 50, which acts as a control means, as shown in Figure 2. The control unit 50 is a control unit that controls the entire printer 1, and in addition to the above-described configuration, it controls the line head 26 and a media transport motor (not shown), etc.

[0057] The control unit 50 is equipped with a CPU 51 and a non-volatile memory 52. ​​The non-volatile memory 52 stores programs PR and various parameters for performing various controls on the printer 1. Program PR contains programs for implementing the various controls described below, and the non-volatile memory 52 stores various parameters necessary for executing program PR. Furthermore, code N1 is data related to cleaning control information described later, code N2 is data related to discharge volume adjustment information described later, and code N3 is data related to discharge area setting information.

[0058] The control unit 50 receives signals from the operation panel 54, and also outputs signals from the control unit 50 to the display unit (not shown) of the operation panel 54 for displaying information. Various setting information input via the operation panel 54 is stored in the non-volatile memory 52. ​​The control unit 50 performs various controls based on the above setting information.

[0059] The control unit 50 is equipped with an interface 53 for communicating with an external computer 90. The control unit 50 acquires recording data, which is data for recording, generated by a printer driver running on the external computer 90 or by a printer driver provided in the control unit 50. Based on this recording data, it controls various mechanical parts, including the line head 26. The recording data also includes information on the size of the media.

[0060] Furthermore, the control unit 50 receives detection signals from various sensors, and the control unit 50 performs necessary control based on these detection signals. Figure 2 shows some of the various sensors, including the upstream sensor 65, the downstream sensor 66, and the temperature and humidity sensor 67. As shown in Figures 3 and 4, the upstream sensor 65 is located upstream of the line head 26, facing the conveyor belt 33. The downstream sensor 66 is located downstream of the line head 26, also facing the conveyor belt 33. The upstream sensor 65 and the downstream sensor 66 are optical sensors equipped with a light-emitting part that emits light toward the conveyor belt 33 and a light-receiving part that receives reflected light from the conveyor belt 33 or the medium. Based on the detection signal from the upstream sensor 65, the control unit 50 can detect the passage of the leading or trailing end of the medium at the location of the upstream sensor 65, and can also detect the passage of the leading or trailing end of the medium at the location of the downstream sensor 66.

[0061] In particular, the control unit 50 detects the passage of the media's leading edge at the upstream sensor 65, and if it fails to detect the passage of the media's leading edge at the downstream sensor 66 after a predetermined time has elapsed, it determines that a media jam has occurred. If the control unit 50 determines that a media jam has occurred, it stops the recording operation. This stopping of the recording operation includes stopping ink ejection from the line head 26 and stopping the drive of the conveyor belt 33 and other conveyor roller pairs.

[0062] The temperature and humidity sensor 67 is located inside the device, and the control unit 50 can determine the temperature and humidity inside the device based on the information received from the temperature and humidity sensor 67. In this embodiment, it is more preferable to place the temperature and humidity sensor 67 near the conveyor belt 33. As will be described in detail later, in this embodiment, the temperature or humidity obtained by the temperature and humidity sensor 67 is used to determine how easily or difficultly the ink adhering to the conveyor belt 33 dries.

[0063] In this embodiment, the control unit 50 cleans the outer surface 33a of the conveyor belt 33 using at least one of the first cleaning unit 35 and the second cleaning unit 40. The control unit 50 can select a first cleaning mode that uses only the first cleaning unit 35, a second cleaning mode that uses both the first cleaning unit 35 and the second cleaning unit 40, and a third cleaning mode that uses only the second cleaning unit 40.

[0064] One example of when the control unit 50 selects the first cleaning mode is during a periodic cleaning operation. The control unit 50 is equipped with means for counting the elapsed time since the last periodic cleaning operation was performed, and when the elapsed time since the last periodic cleaning operation reaches a predetermined time, it performs the periodic cleaning operation. The first cleaning mode is also performed after a recording job has finished and when the printer 1 transitions to a standby state.

[0065] One example of when the control unit 50 selects the second cleaning mode is when a media jam occurs, stopping the recording operation, and the user removes the media and presses the OK button on the operation panel 54. When a media jam occurs in this way, there is a risk that ink may have been mistakenly ejected onto the transport belt 33 and adhered to it, so the control unit 50 performs a cleaning operation using the second cleaning mode. Note that the pre-ejection described below applies to the second cleaning mode, but is not limited to it.

[0066] The control unit 50 selects the third cleaning mode when the number of double-sided recordings reaches a predetermined value, or when there is a risk of condensation occurring on the conveyor belt 33. The control unit 50 is equipped with means for counting the number of double-sided recordings, and when the number of double-sided recordings reaches a predetermined value, the control unit 50 performs a cleaning operation in the third cleaning mode. This is because, when double-sided recording is performed, the first side, which is recorded first, comes into contact with the conveyor belt 33 when recording on the opposite second side, and there is a risk of ink adhering to the conveyor belt 33. Also, if condensation occurs on the conveyor belt 33, there is a risk of the medium getting wet, so the control unit 50 performs a cleaning operation in the third cleaning mode. Examples of situations in which there is a risk of condensation occurring on the conveyor belt 33 include a sudden change in humidity or a sudden rise in temperature from a low-temperature state.

[0067] Next, we will explain the preliminary discharge when cleaning the conveyor belt 33 using the first cleaning unit 35. Preliminary discharge when cleaning the conveyor belt 33, as will be explained in more detail later, is the intentional discharge of ink toward the conveyor belt 33 in order to improve the sliding surface between the conveyor belt 33 and the blade 36 before the conveyor belt 33 is cleaned by the blade 36. Figure 5 shows the control flow when cleaning the conveyor belt 33 using the first cleaning unit 35. When the control unit 50 executes a belt cleaning operation using the first cleaning unit 35, i.e., the blade 36 (Yes in step S101), it performs a preliminary discharge determination (step S102).

[0068] Step S102's preliminary discharge determination includes determining whether or not to perform preliminary discharge, and if so, the discharge position and amount of ink on the conveyor belt 33, as well as the starting position for cleaning by the blade 36. These details will be explained later.

[0069] If the control unit 50 determines that pre-discharge is necessary (Yes in step S103), it adjusts the discharge start position (step S104). This discharge start position adjustment is an operation to rotate the conveyor belt 33 so that the position where pre-discharge begins faces the line head 26. In this embodiment, when it is determined that a jam of the medium has occurred and the drive of the conveyor belt 33 is stopped, the position where pre-discharge begins has passed the contact position of the blade 36 in the forward direction, so the discharge start position adjustment mainly involves the reverse operation of the conveyor belt 33. Then the control unit 50 performs preliminary dispensing (step S105).

[0070] Next, the control unit 50 adjusts the cleaning start position for the blade 36 (step S106). This cleaning start position adjustment mainly involves the forward rotation of the conveyor belt 33 if preliminary discharge (step S105) is being performed. If preliminary discharge (step S105) is not performed, the adjustment of the cleaning start position in step S106 will mainly be performed by the reverse rotation of the conveyor belt 33. As mentioned above, at the time when it is determined that a jam of the medium has occurred and the drive of the conveyor belt 33 is stopped, the position where preliminary discharge will start has passed the contact position of the blade 36 in the forward direction. By adjusting the cleaning start position in step S106, the blade 36 will be positioned at the cleaning start position.

[0071] Next, the control unit 50 switches the blade 36 from a separated state to a contact state (step S107), and in that state rotates the conveyor belt 33 forward by a predetermined amount to clean the conveyor belt 33 with the blade 36 (step S108). Once the cleaning of the conveyor belt 33 by the blade 36 is complete, the blade 36 is switched back from the contact state to a separated state (step S109).

[0072] Next, we will explain in detail the preliminary discharge determination process in step S102. Figure 6 shows an example of ink being mistakenly ejected onto the conveyor belt 33 due to a jam in the media, with region B2 indicating the area of ​​mis-ejected ink. Region B2 is a part of the entire recording area of ​​the media. Region B2 shown in the example in Figure 6 includes areas where ink has landed and areas where it has not. In particular, the area indicated by the symbol Na in the media width direction is the area along the direction of travel of the conveyor belt 33 where there are no areas where ink has landed at all. Note that in Figure 6, the direction of travel of the conveyor belt 33 is upward (+F direction).

[0073] Since the impact area is a wet area, the sliding between the conveyor belt 33 and the blade 36 is good. In contrast, in the non-impact area, or even in the impact area if the amount of ink is small, the sliding between the conveyor belt 33 and the blade 36 deteriorates. In particular, in range Na, there is no area of ​​ink impact along the direction of travel of the conveyor belt 33, so the sliding between the conveyor belt 33 and the blade 36 is the worst. If the sliding surface between the conveyor belt 33 and the blade 36 is poor, it may cause damage such as peeling, chipping, or wear to the edge of the blade 36 that is in contact with the conveyor belt 33, potentially preventing the blade 36 from maintaining its function. Therefore, the control unit 50 performs a preliminary discharge of ink from the line head 26 to the conveyor belt 33 based on pre-set cleaning control information.

[0074] In this manner, when the control unit 50 performs a cleaning operation to clean the conveyor belt 33 with the blade 36, it performs a preliminary discharge of ink from the line head 26 to the conveyor belt 33 based on pre-set cleaning control information. This preliminary discharge improves the sliding properties between the conveyor belt 33 and the blade 36, thereby maintaining the function of the blade 36.

[0075] The following describes an example of cleaning control information. It is assumed that the cleaning control information described below is pre-stored in the non-volatile memory 52 (see Figure 2) of the control unit 50. The tables shown in Figures 7(a), (b), (c), and (d) are examples of cleaning control information. Hereafter, temperature and humidity refer to the temperature and humidity obtained by the temperature and humidity sensor 67 (see Figure 2). Furthermore, hereafter, temperature and humidity refer to the temperature and humidity when performing a cleaning operation in which the conveyor belt 33 is cleaned by the blade 36, as an example. Furthermore, in the following, "discharge duty" refers to the discharge duty when ink is mistakenly discharged from the line head 26. Here, the discharge duty is the ratio of the recorded area within a predetermined area of ​​the medium; a lower discharge duty means less ink is discharged, and a higher discharge duty means more ink is discharged.

[0076] Furthermore, the discharge duty cycle can be the discharge duty cycle in the area where ink is actually discharged onto the conveyor belt 33 (for example, area B2 in Figure 6). Hereinafter, this will be referred to as the "actual discharge duty cycle." The control unit 50 can acquire the actual discharge duty cycle based, for example, the amount of ink discharged from the time the leading edge of the medium is detected by the upstream sensor 65 until the drive of the conveyor belt 33 is stopped, and the corresponding recording area (for example, area B2 in Figure 6). Since the actual discharge duty cycle is based on the amount of ink actually discharged onto the conveyor belt 33, it can be said to more accurately reflect the condition of the conveyor belt 33. Furthermore, although area B2 in Figure 6 is only a part of the entire recording area, the ejection duty cycle for the entire recording area may also be used. Hereafter, this will be referred to as the "overall ejection duty cycle." The control unit 50 can obtain the overall ejection duty cycle based on the recorded data. The overall ejection duty cycle does not require measuring the actual amount of ink ejected onto the transport belt 33, and can be calculated more easily than the actual ejection duty cycle. The control unit 50 adopts either the actual discharge duty cycle or the overall discharge duty cycle based on the program PR (see Figure 2) or the specified cleaning control information. Thus, in this specification, the discharge duty cycle when ink is mis-discharged does not mean only the discharge duty cycle in the area where ink is actually discharged onto the conveyor belt 33.

[0077] Figures 7(a), (b), (c), and (d) show examples where cleaning control information is set with humidity and discharge duty cycle as the conditions for performing pre-discharge. In Figure 7, regarding the discharge duty cycle, the first event is considered "suitable" if the discharge duty cycle is lower than the first discharge duty cycle, and "unsuitable" otherwise. Hereafter, "suitable" means suitable for pre-discharge, and "unsuitable" means unsuitable for pre-discharge. The term "appropriate" for the discharge duty cycle means the occurrence of the first event described above. In this embodiment, the first discharge duty cycle can also be rephrased as the threshold for the discharge duty cycle. When the first event occurs, with a discharge duty cycle lower than the first discharge duty cycle, the slipperiness between the conveyor belt 33 and the blade 36 is worse than when the first event does not occur, which is advantageous for performing pre-discharge.

[0078] Regarding humidity, the second event, where the humidity is lower than the first humidity, is considered "suitable," while all other cases are considered "unsuitable." "Suitable" humidity means the occurrence of the second event described above. In this embodiment, the first humidity can be rephrased as the humidity threshold. When the second event, where the humidity is lower than the first humidity, occurs, the ink dries more easily than when the second event does not occur, and the slipperiness between the conveyor belt 33 and the blade 36 is poor, which is advantageous for performing pre-discharge.

[0079] Next, in Figure 7, "ON" means that pre-discharge will be performed, and "OFF" means that pre-discharge will not be performed. In the examples shown in Figures 7(a), (b), (c), and (d), the setting is "ON," meaning the control unit 50 performs preliminary discharge, when the first and second events occur simultaneously. The setting is "OFF," meaning the control unit 50 does not perform preliminary discharge, when the first and second events do not occur simultaneously. Even if the first event described above occurs, if the second event described above does not occur, it is easier to ensure smooth sliding between the conveyor belt 33 and the blade 36. Conversely, even if the second event described above occurs, if the first event described above does not occur, it is easier to ensure smooth sliding between the conveyor belt 33 and the blade 36. As shown in the example in Figure 7, in such cases, pre-discharge is not performed, so unnecessary ink consumption can be suppressed.

[0080] In the example shown in Figure 7(a), the discharge duty cycle is divided into "low" and "high" ranges, and the threshold first discharge duty cycle defines the boundary between "low" and "high." However, as shown in Figures 7(b) and 7(d), the discharge duty cycle may also be divided into "low," "medium," and "high" ranges, and the threshold first discharge duty cycle may define the boundary between "medium" and "high." Similarly, in the example in Figure 7(a), humidity is divided into "low" and "high" ranges, and the first threshold humidity defines the boundary between "low" and "high." However, as shown in Figures 7(c) and 7(d), humidity may also be divided into "low," "medium," and "high" ranges, and the first threshold humidity may define the boundary between "low" and "medium."

[0081] Note that in Figure 7(b), "medium" humidity is treated as "unsuitable," but as shown in Figure 8(a), "medium" humidity can also be treated as "suitable." Furthermore, in the examples shown in Figures 7(a), (b), (c), and (d), the setting is "ON," meaning the control unit 50 performs preliminary discharge, when the first and second events occur simultaneously, and "OFF," meaning the control unit 50 does not perform preliminary discharge, when the first and second events do not occur simultaneously. However, some of these settings may be modified. For example, in the example in Figure 7(d), humidity "medium" and "low" are considered "suitable" for the occurrence of the second event. In the case of humidity "medium" and discharge duty cycle "medium", the setting is "ON" in the above example, but even with humidity "medium", if the discharge duty cycle is "medium", it may be set to "OFF" as long as the slipperiness between the conveyor belt 33 and the blade 36 is ensured. An example of this is shown in Figure 8(b).

[0082] Furthermore, the cleaning control information is not limited to humidity and ejection duty cycle, but may also include temperature and at least one of the elapsed time since the ink was ejected as conditions for performing pre-ejection. That is, the cleaning control information may include one or more of the ejection duty cycle, humidity, temperature, and elapsed time since the ink was ejected when ink was ejected from the line head 26 as conditions for performing pre-ejection. In this case, it is preferable to set the system so that at least one of the following conditions acts on the execution of pre-ejection: a first event where the ejection duty cycle is lower than the first ejection duty cycle, a second event where the humidity is lower than the first humidity, a third event where the temperature is higher than the first temperature, and a fourth event where the elapsed time is longer than the first elapsed time. This allows for appropriate pre-discharge depending on the conditions during the cleaning operation, thus maintaining the functionality of the blade 36 material. Furthermore, if pre-ejection is not required, it will not occur, thus reducing unnecessary ink consumption. Furthermore, as stated above, the fact that each of the above events affects the execution of preliminary discharge does not mean that preliminary discharge will always be performed when each event occurs, but rather that the occurrence of each event works to the advantage of executing preliminary discharge. Furthermore, the control unit 50 does not need to store information related to events other than those necessary for determining pre-discharge in the non-volatile memory 52.

[0083] Furthermore, the start timing of the elapsed time since the ink was accidentally ejected can be set to the initial ink ejection timing for the entire recording surface, the final ink ejection timing for the entire recording surface, or a timing midway between the initial and final ink ejection timings for the entire recording surface. Alternatively, the start timing of the elapsed time can be set to the initial ink ejection timing for the area where ink is actually ejected onto the conveyor belt 33 (for example, area B2 in Figure 6), the final ink ejection timing for the area where ink is actually ejected onto the conveyor belt 33, or a timing midway between the initial and final ink ejection timings for the area where ink is actually ejected onto the conveyor belt 33. Furthermore, the timing of the end of the elapsed time can be set to the time when the user removes the media and presses the OK button on the operation panel 54 after a media jam occurs and the recording operation stops. In the following, when simply referring to "elapsed time," it means the elapsed time since the ink was mistakenly ejected, as determined by the control unit 50 as described above.

[0084] The following explains the case where temperature and elapsed time are used. Regarding temperature, a third event where the temperature is higher than the first temperature is considered "suitable," while all other cases are considered "unsuitable." "Suitable" temperature means the occurrence of the above third event. In this embodiment, the first temperature can be rephrased as the temperature threshold. When the third event, where the temperature is higher than the first temperature, occurs, the ink dries more easily and the slipperiness between the conveyor belt 33 and the blade 36 is worse than when the third event does not occur, which is advantageous for pre-discharge. Regarding the elapsed time, if the elapsed time is longer than the first elapsed time, it is considered "suitable," and otherwise it is considered "unsuitable." "Suitable" elapsed time means that the above-mentioned fourth event occurs. In this embodiment, the first elapsed time may be rephrased as the elapsed time threshold. When the fourth event occurs, where the elapsed time is longer than the first elapsed time, the ink has dried more advanced than when the fourth event has not occurred, and the slipperiness between the conveyor belt 33 and the blade 36 is poor, which is advantageous for performing pre-discharge. By replacing one or both of the first or second events in the examples of Figures 7(a), (b), (c), and (d) with these third or fourth events, temperature and elapsed time can be adopted. Of course, either the third or fourth event alone may be used as the execution condition for pre-discharge.

[0085] If temperature, elapsed time, or both are further applied to the examples in Figures 7(a), (b), (c), and (d), then in the examples in Figures 7(a), (b), (c), and (d), if the temperature becomes "suitable" or the elapsed time becomes "suitable", then a preliminary discharge is performed by finally turning "ON". If the temperature becomes "unsuitable" or the elapsed time becomes "unsuitable", then even if the temperature becomes "ON" in the examples in Figures 7(a), (b), (c), and (d), no preliminary discharge is performed.

[0086] As explained above, in the examples of Figures 7(a), (b), (c), and (d), humidity and discharge duty cycle are used as the conditions for pre-discharge execution, but it is also acceptable to use only one of the following conditions for pre-discharge execution: humidity, discharge duty cycle, temperature, or elapsed time. Specifically, if the discharge duty cycle is the only condition for performing pre-discharge, pre-discharge is performed when a first event occurs in which the discharge duty cycle is lower than the first discharge duty cycle. Alternatively, if humidity is the sole condition for performing pre-discharge, pre-discharge is performed when a second event occurs in which the humidity is lower than the first humidity. Alternatively, if temperature is the sole condition for performing pre-discharge, pre-discharge is performed when a third event occurs where the temperature is higher than the first temperature. Alternatively, if only elapsed time is used as the condition for performing a preliminary discharge, the preliminary discharge will be performed if a fourth event occurs where the elapsed time is longer than the first elapsed time.

[0087] Next, the control unit 50 may be configured to adjust the amount of ink ejected during pre-ejection based on preset ejection amount adjustment information. By setting the amount of ink ejected during pre-ejection to an appropriate amount, the sliding surface between the conveyor belt 33 and the blade 36 is improved, and unnecessary ink consumption can be suppressed.

[0088] Furthermore, the above-mentioned discharge volume adjustment information preferably includes one or more of the discharge duty cycle, humidity, temperature, and elapsed time as conditions for adjusting the ink discharge volume, and is set so that at least one of the following—a decrease in discharge duty cycle, a decrease in humidity, an increase in temperature, and an increase in elapsed time—acts on increasing the ink discharge volume during pre-discharge. This increases the ink discharge volume when the slippage between the conveyor belt 33 and the blade 36 is poor, thereby appropriately improving the slippage between the conveyor belt 33 and the blade 36. Furthermore, the control unit 50 does not need to store information related to conditions other than those necessary for adjusting the ink ejection amount, such as ejection duty cycle, humidity, temperature, and elapsed time, in the non-volatile memory 52.

[0089] The following is a specific example of the ink ejection volume adjustment information, with reference to Figure 9. The coefficient shown in Figure 9 is a coefficient multiplied by the standard ink ejection volume Sh when performing pre-ejection. Therefore, the smaller the multiplier, the smaller the ink ejection volume during pre-ejection, and conversely, the larger the coefficient, the larger the ink ejection volume during pre-ejection. Figure 9(a) shows the coefficients set for the discharge duty cycle Q. The discharge duty cycle Q increases in the order of Q1, Q2, and Q3, and the coefficient decreases as the discharge duty cycle Q increases. This is because the sliding performance between the conveyor belt 33 and the blade 36 improves as the discharge duty cycle Q increases. In other words, the coefficient decreases as the discharge duty cycle Q decreases.

[0090] Figure 9(b) shows the coefficients set for different humidity levels H. Humidity H increases in the order of H1, H2, H3, and H4, and the coefficient decreases as humidity H increases. This is because as humidity H increases, the ink dries more slowly, and the slipperiness between the conveyor belt 33 and the blade 36 is maintained. In other words, the coefficient increases as humidity H decreases.

[0091] Figure 9(c) shows the coefficients set for different temperatures S. The temperature S increases in the order S1, S2, S3, and S4, and the coefficients increase as the temperature S increases. This is because as the temperature S increases, the ink dries faster, and the slipperiness between the conveyor belt 33 and the blade 36 deteriorates. In other words, the coefficients decrease as the temperature S decreases.

[0092] Figure 9(d) shows the coefficients set for elapsed time T. Elapsed time T increases in the order of T1, T2, and T3, and the coefficients increase as elapsed time T increases. This is because as elapsed time T increases, the ink dries more rapidly, and the sliding properties between the conveyor belt 33 and the blade 36 deteriorate. In other words, the coefficients decrease as elapsed time T decreases.

[0093] As described above, a decrease in the ejection duty cycle Q, a decrease in humidity H, an increase in temperature S, and an increase in elapsed time T all contribute to an increase in the ink ejection volume during the preliminary ejection. The coefficient multiplied by the standard ink ejection amount Sh may be any one of the following: the coefficient for ejection duty cycle Q, the coefficient for elapsed time T, or the coefficient for humidity H. Alternatively, the standard ink ejection volume Sh may be multiplied by both the coefficient of elapsed time T and the coefficient of ejection duty cycle Q. Alternatively, the standard ink ejection volume Sh may be multiplied by both the coefficient of the ejection duty cycle Q and the coefficient of humidity H. Alternatively, the coefficients for elapsed time T, ejection duty cycle Q, and humidity H may all be multiplied by the standard ink ejection volume Sh. Alternatively, the standard ink ejection volume Sh may be multiplied by all of the following coefficients: ejection duty cycle Q, humidity H, temperature S, and elapsed time T. In other words, the ejection volume adjustment information only needs to include one or more of the following as conditions for adjusting the ink ejection volume when performing pre-ejection: ejection duty cycle Q, humidity H, temperature S, and elapsed time T.

[0094] Furthermore, the discharge volume adjustment information may include the discharge duty cycle Q as a condition for determining the ink discharge volume during preliminary discharge, and the control unit 50 may calculate the discharge duty cycle Q for each region partitioned along the width direction (Y-axis direction), which is the direction intersecting the direction of travel of the conveyor belt 33 (+F direction), and adjust the ink discharge volume for each region. Figure 10 shows such an example, where the labels Y1, Y2, Y3, Y4, Y5, and Y6 indicate multiple regions demarcated along the width direction (Y-axis direction). Each region constitutes region B2.

[0095] Region Y3 is an area where no ink is being ejected and the slipperiness between the transport belt 33 and the blade 36 is poor. Therefore, ink at the standard ink ejection amount Sh is ejected to this region (pre-ejection region Db2). In contrast, for example, a smaller amount of ink than the standard ink ejection amount Sh is ejected to regions Y1 and Y2 (pre-ejection region Db1), and an even smaller amount of ink is ejected to regions Y4, Y5, and Y6, where the most ink is being ejected (pre-ejection region Db3). The ink ejection amount in each region is adjusted by multiplying the standard ink ejection amount Sh by the coefficient shown in Figure 9(a) as an example. In this manner, the control unit 50 calculates the discharge duty cycle Q for each region partitioned along the width direction and adjusts the ink discharge amount for each region. This allows the ink discharge amount during pre-discharge to be adjusted within a finer range, resulting in better sliding between the conveyor belt 33 and the blade 36, and also suppressing unnecessary ink consumption.

[0096] In the above example, the ejection duty cycle Q was calculated for each region partitioned along the width direction, and the ink ejection amount was adjusted for each region. However, in this case, one or more of the coefficients for humidity H, temperature S, and elapsed time T, as explained with reference to Figures 9(b), (c), and (d), may also be applied.

[0097] Next, we will explain the ink ejection position when performing preliminary ejection. In the example shown in Figure 10, the control unit 50 performs pre-discharge so that the pre-discharge areas Db1, Db2, and Db3 come into contact with the blade 36 before the area B2 where ink has landed due to misdischarge on the transport belt 33. In Figure 9, the pre-discharge areas Db1, Db2, and Db3 are set in the +F direction relative to area B2. By setting the pre-discharge position in this way, the blade 36 will clean the area B2 that was accidentally discharged while it was already wet, thus more reliably maintaining the function of the blade 36.

[0098] In the example shown in Figure 10, the preliminary discharge regions Db1, Db2, and Db3 do not overlap with region B2, but it is acceptable for parts of the preliminary discharge regions Db1, Db2, and Db3 to overlap with region B2. Furthermore, if the preliminary discharge areas Db1, Db2, and Db3 do not need to come into contact with the blade 36 before area B2, then it is acceptable for all of the preliminary discharge areas Db1, Db2, and Db3 to overlap with area B2.

[0099] The control unit 50 may also perform pre-discharge on the conveyor belt 33 to avoid areas where ink has landed due to misdischarge. Pre-discharge to avoid areas where ink has landed due to misdischarge means, for example, discharging ink to areas inside region B2 in Figure 6 where no ink has landed. By performing pre-discharge while avoiding already wet areas, unnecessary ink consumption can be suppressed. In this case as well, the discharge volume adjustment described with reference to Figure 9 may be performed.

[0100] Furthermore, when performing preliminary ejection, the control unit 50 may be configured to select between a first ejection mode, which ejects ink in a manner that avoids areas on the conveyor belt 33 where ink has landed due to mis-ejection, and a second ejection mode, which ejects ink towards both areas on the conveyor belt 33 where ink has landed due to mis-ejection and areas where it has not. The ejection area setting information is information stored in the non-volatile memory 52 (see Figure 2) provided by the control unit 50. In the example shown in Figure 6, when the first ejection mode is selected, ink is ejected to the areas inside region B2 where ink has not yet landed. When the second ejection mode is selected, ink is ejected to both the areas inside region B2 where ink has landed and the areas where ink has not yet landed. This allows for reduced ink consumption in the first ejection mode. In the second ejection mode, ink is also ejected to areas where ink has landed on the conveyor belt 33 due to mis-ejection, which softens the areas where ink has landed and enhances the cleaning effect.

[0101] The above discharge area setting information may be configured such that the control unit 50 selects the first discharge mode when the humidity exceeds the standard humidity, and selects the second discharge mode when the humidity is below the standard humidity. This ensures that the first discharge mode is selected when the area on the conveyor belt 33 where ink has landed due to misdischarge has not yet dried, thereby reducing ink consumption. Conversely, when the area on the conveyor belt 33 where ink has landed due to misdischarge has already dried, the second discharge mode is selected, which softens the area on the conveyor belt 33 where ink has landed due to misdischarge, thereby improving the cleaning effect.

[0102] In each of the above embodiments, the control unit 50 rotates the conveyor belt 33 while maintaining the blade 36 in a separated state until the blade 36 approaches the area on the conveyor belt 33 where ink has landed, and then switches the blade 36 from a separated state to a contact state when the blade 36 approaches the area on the conveyor belt 33 where ink has landed. As a result, in the example shown in Figure 6, cleaning by the blade 36 is performed from position F1, which is the +F end of region B2, or from a position slightly +F from F1 toward the -F direction. This type of control reduces the period during which the blade 36 is in contact with areas on the conveyor belt 33 where ink has not landed, thereby more reliably maintaining the function of the blade 36.

[0103] Furthermore, the pre-ejection described above applies to cleaning the transport belt 33 after accidental ink ejection, but is not limited to this; it may also be applied to the periodic cleaning operation or other cleaning operations mentioned above. In this embodiment, the line head 26 is provided with nozzle rows for each ink color: cyan, magenta, yellow, and black. However, the nozzle row used for pre-discharge may be any of the ink color nozzle rows, or all nozzle rows may be used for pre-discharge. Furthermore, if the slipperiness between the conveyor belt 33 and the blade 36 differs depending on the ink color, the ink of the color with the best slipperiness among the multiple ink colors may be used for pre-discharge. Furthermore, although the temperature and humidity sensor 67 is configured to be installed inside the device, it is not limited to this and may be installed outside the device. Also, the temperature sensor and humidity sensor may be installed separately, in which case at least one of them may be installed outside the device.

[0104] Furthermore, it goes without saying that the present invention is not limited to the embodiments described above, and various modifications are possible within the scope of the invention as described in the claims, and these modifications are also included within the scope of the present invention. [Explanation of Symbols]

[0105] 1... Inkjet printer, 2... Main unit, 3... First media cassette, 4... Second media cassette, 5... Ink storage section, 9, 10... Pick rollers, 11, 12... Feeding roller pairs, 13, 14, 15, 16, 18, 19, 20, 21, 22... Conveyor roller pairs, 17... Conveyor roller pairs, 23, 24... Flaps, 25... Head unit, 26... Line head, 27... Discharge tray, 29... Charging roller, 30... Belt unit, 31... Drive pulley, 32... Driven pulley, 33... Conveyor belt, 33a... Outer surface, 34... Support roller -, 35...First cleaning unit, 36...Blade, 37...Fixing member, 38...Rotating shaft, 40...Second cleaning unit, 41...Cleaning sheet, 42...Drive pulley, 43, 44...Driven pulley, 45...Tensioner, 50...Control unit, 51...CPU, 52...Non-volatile memory, 53...Interface, 54...Operation panel, 57...Belt drive motor, 58...Belt charging unit, 59...Blade drive unit, 60...Unit drive unit, 61...Sheet drive motor, 65...Upstream sensor, 66...Downstream sensor, 67...Temperature and humidity sensor, 90...External computer, P...Medium

Claims

1. A liquid dispensing unit that dispenses liquid into a medium, Opposite the liquid discharge section is a conveyor belt for transporting the medium, A cleaning member for cleaning the conveyor belt by contacting the conveyor belt, the cleaning member being capable of switching between a contact state in which it is in contact with the conveyor belt and a separation state in which it is separated from the conveyor belt, The system comprises a control unit that controls the liquid discharge operation by the liquid discharge unit, the rotation operation of the conveyor belt, and the state switching of the cleaning member, When the control unit performs a cleaning operation to clean the conveyor belt with the cleaning member, it performs a preliminary discharge of liquid from the liquid discharge unit to the conveyor belt based on pre-set cleaning control information. The cleaning control information includes, as the execution conditions for the preliminary discharge, one or more of the following: the discharge duty cycle, humidity, temperature, and the elapsed time since the erroneous discharge of liquid from the liquid discharge unit. At least one of the following events is set to act on the execution of the pre-discharge: a first event in which the discharge duty cycle is lower than the first discharge duty cycle, a second event in which the humidity is lower than the first humidity, a third event in which the temperature is higher than the first temperature, and a fourth event in which the elapsed time is longer than the first elapsed time. A liquid dispensing device characterized by the following features.

2. In the liquid dispensing device according to claim 1, At least one of the following events is set to act on the execution of the pre-discharge: a first event in which the discharge duty cycle is lower than the first discharge duty cycle, a second event in which the humidity is lower than the first humidity, a third event in which the temperature is higher than the first temperature, and a fourth event in which the elapsed time is longer than the first elapsed time. A liquid dispensing device characterized by the following features.

3. In the liquid dispensing device according to claim 2, the cleaning control information uses the dispensing duty cycle and humidity as the execution conditions for the preliminary dispensing, The control unit is configured to perform the preliminary discharge if the first event and the second event occur simultaneously, and not to perform the preliminary discharge if the first event and the second event do not occur simultaneously. A liquid dispensing device characterized by the following features.

4. In the liquid dispensing device according to claim 2 or claim 3, the control unit adjusts the amount of liquid to be dispensed when performing the preliminary dispensing based on preset dispensing amount adjustment information. A liquid dispensing device characterized by the following features.

5. In the liquid dispensing device according to claim 4, the dispensing amount adjustment information includes one or more of the dispensing duty cycle, humidity, temperature, and elapsed time as conditions for adjusting the liquid dispensing amount, At least one of the following—a decrease in the discharge duty cycle, a decrease in humidity, an increase in temperature, and an increase in elapsed time—is set to act on an increase in the liquid discharge amount during the preliminary discharge. A liquid dispensing device characterized by the following features.

6. In the liquid dispensing device according to claim 5, the dispensing amount adjustment information includes the dispensing duty cycle as a condition for determining the liquid dispensing amount, The control unit calculates the discharge duty cycle for each region partitioned along the width direction which intersects the direction of travel of the conveyor belt, and adjusts the liquid discharge amount for each region. A liquid dispensing device characterized by the following features.

7. In the liquid dispensing device according to any one of claims 2 to 6, the control unit performs the preliminary dispensing such that the area that has been pre-dispensed on the conveyor belt comes into contact with the cleaning member before the area where the liquid has landed due to the erroneous dispensing. A liquid dispensing device characterized by the following features.

8. In the liquid dispensing device according to any one of claims 2 to 7, the control unit performs the preliminary dispensing so as to avoid the portion of the conveyor belt where the liquid has landed due to the erroneous dispensing. A liquid dispensing device characterized by the following features.

9. In the liquid dispensing device according to any one of claims 2 to 7, when the pre-dispensing is performed, the control unit shall, based on the pre-set dispensing area setting information, The first discharge mode in the conveyor belt is to discharge the liquid in a manner that avoids the area where the liquid has landed due to the misdischarge, In the aforementioned conveyor belt, a second discharge mode is selected in which liquid is discharged towards the area where the liquid has landed due to the misdischarge and the area where it has not landed. A liquid dispensing device characterized by the following features.

10. In the liquid dispensing device according to claim 9, the dispensing area setting information is configured such that if the humidity exceeds a reference humidity, the control unit selects the first dispensing mode, and if the humidity is less than or equal to the reference humidity, the control unit selects the second dispensing mode. A liquid dispensing device characterized by the following features.

11. In a liquid dispensing device according to any one of claims 1 to 10, the control unit rotates the conveyor belt while maintaining the cleaning member in the separated state until the cleaning member faces the area on the conveyor belt where liquid has landed, and when the cleaning member faces the area on the conveyor belt where liquid has landed, switches the cleaning member from the separated state to the contact state. A liquid dispensing device characterized by the following features.

12. A liquid dispensing unit that dispenses liquid into a medium, Opposite the liquid discharge section is a conveyor belt for transporting the medium, A control method for a liquid dispensing device comprising a cleaning member for cleaning the conveyor belt by contacting the conveyor belt, the cleaning member being capable of switching between a contact state in contact with the conveyor belt and a separation state in separation from the conveyor belt, When cleaning the conveyor belt with the cleaning member, a preliminary discharge is performed, in which liquid is discharged from the liquid discharge unit onto the conveyor belt in advance, based on pre-set cleaning control information. The cleaning control information includes, as the execution conditions for the preliminary discharge, one or more of the following: the discharge duty cycle, humidity, temperature, and the elapsed time since the erroneous discharge of liquid from the liquid discharge unit. At least one of the following events is set to act on the execution of the pre-discharge: a first event in which the discharge duty cycle is lower than the first discharge duty cycle, a second event in which the humidity is lower than the first humidity, a third event in which the temperature is higher than the first temperature, and a fourth event in which the elapsed time is longer than the first elapsed time. A method for controlling a liquid dispensing device, characterized by the following:

13. A liquid dispensing unit that dispenses liquid into a medium, Opposite the liquid discharge section is a conveyor belt for transporting the medium, A program executed by the control unit of a liquid dispensing device, which includes a cleaning member that cleans the conveyor belt by contacting the conveyor belt, and which is capable of switching between a contact state in which it is in contact with the conveyor belt and a separation state in which it is separated from the conveyor belt, When cleaning the conveyor belt with the cleaning member, the cleaning member includes a step of pre-discharging liquid from the liquid discharge unit to the conveyor belt based on pre-set cleaning control information. The cleaning control information includes, as the execution conditions for the preliminary discharge, one or more of the following: the discharge duty cycle, humidity, temperature, and the elapsed time since the erroneous discharge of liquid from the liquid discharge unit. At least one of the following events is set to act on the execution of the pre-discharge: a first event in which the discharge duty cycle is lower than the first discharge duty cycle, a second event in which the humidity is lower than the first humidity, a third event in which the temperature is higher than the first temperature, and a fourth event in which the elapsed time is longer than the first elapsed time. A program characterized by the following features.

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