EP4678403A1

EP4678403A1 - Printer, inkjet printer, and moisturizing device

Info

Publication number: EP4678403A1
Application number: EP24770682.3A
Authority: EP
Inventors: Sho Koshiba; Takehiko Yoshida; Kazuki Koike; Tomoya Kawai; Haruki TAKATERA
Original assignee: Mimaki Engineering Co Ltd
Current assignee: Mimaki Engineering Co Ltd
Priority date: 2023-03-10
Filing date: 2024-03-07
Publication date: 2026-01-14
Also published as: CN120752142A; WO2024190576A1

Abstract

Provided is a printer that enables movement of a tension bar in a forward and downward direction, brings the tension bar into contact, from obliquely rear and upward, with a medium after printing that is moving downward, and even when applying tension to the medium via the force of gravity exerted on the tension bar, can inhibit fluctuations in tension of the medium applied by the tension bar when the position of the tension bar has fluctuated. In this printer, a medium printed on by a printing mechanism moves forward and then moves downward. A tension bar 40 contacts, from obliquely rear and upward, the medium that is moving downward, and applies tension to the medium via the force of gravity exerted on the tension bar 40. A tension applying mechanism 12 includes a guide part 43 that linearly guides the tension bar 40 in a forward and downward direction, and an urging member 44 for urging the tension bar 40 toward obliquely rear and upward.

Description

TECHNICAL FIELD

The present invention relates to a printer for performing printing on a long medium. The present invention also relates to an inkjet printer for performing printing on a long medium. The present invention also relates to a moisturizing device for moisturizing a nozzle surface of a head unit including a plurality of inkjet heads. The present invention also relates to an inkjet printer including such a moisturizing device.

Description of Related Art

Conventionally, a printer (inkjet printer) for performing printing on a long medium is known (see, for example, Patent Document 1). The printer described in Patent Document 1 includes a printer body that performs printing on a medium, a winding roll holding unit that holds a winding roll as a medium after printing wound in a roll shape, and a columnar tension bar that contacts the medium after printing to apply tension to the medium. The tension bar contacts the medium after printing from above to apply tension to the medium.
Further, conventionally, an inkjet printer for performing printing on a long medium is known (see, for example, Patent Document 2). The inkjet printer described in Patent Document 2 includes an inkjet head (recording head) that ejects ink toward a medium, a carriage on which the inkjet head is mounted, a printing platen that is disposed below the inkjet head and on which a medium when printing is placed, and a fan that sucks and holds the medium placed on the printing platen onto the printing platen. The upper surface of the printing platen is a support surface for supporting the medium. The printing platen has a plurality of suction holes (through holes) for sucking the medium.
In the inkjet printer described in Patent Document 2, a space defined by the printing platen, two wall members, a bottom member, and the like is formed on the lower side of the printing platen. The fan is attached to the bottom member and sucks air from the space below the printing platen. That is, when the fan operates, air is discharged from the inside of the space below the printing platen. When air is discharged from the inside of the space below the printing platen, the medium is sucked onto the support surface of the printing platen and held on the printing platen. The fan operates when performing printing on the medium.
Furthermore, conventionally, a moisturizing device for moisturizing a nozzle surface of a head unit including a plurality of inkjet heads is known (see, for example, Patent Document 3). The moisturizing device described in Patent Document 3 includes a cap disposed below the nozzle surface of the head unit during non-recording operation, and a moisturizing liquid supply unit that supplies water as a moisturizing liquid into the cap. At the time of non-recording operation, the head unit mounted on the carriage moves to the upper side of the cap, the nozzle surface of the head unit is moisturized, and pressure purge is performed to eject ink from the nozzles of the inkjet head to the cap.
In the moisturizing device described in Patent Document 3, the cap includes a housing, a spongy member disposed in the housing, and a first discharge pipe for discharging ink and water in the cap. When the nozzle surface is moisturized, the upper surface of the spongy member faces the nozzle surface from below while maintaining a constant gap with the nozzle surface. The moisturizing liquid supply unit includes a water tank and a liquid feeding pump that feeds water from the water tank into the cap. The liquid feeding pump is driven under the control of the controller, and supplies water into the cap so that the water supply amount is 50 mass% or more with respect to the amount of ink to be pressurized and purged.

Citation List

Patent Document

Patent Document 1: Japanese Patent Application Laid-Open No. 2019-195973
Patent Document 2: Japanese Patent Application Laid-Open No. 2015-74090
Patent Document 3: Japanese Patent No. 6464793

SUMMARY OF THE INVENTION

PROBLEMS TO BE SOLVED BY THE INVENTION

The inventor of the present application has developed a printer for performing printing on a long medium. A printer under development includes a printing mechanism that performs printing on a long medium, a winding roll holding unit that holds a winding roll as a medium after printing wound in a roll shape, and a tension bar that applies tension to the medium by coming into contact with the medium after printing between the printing mechanism and the winding roll holding unit. In this printer, the width direction of the medium coincides with the left and right direction orthogonal to the up and down direction, and the thickness direction of the medium when printing is performed by the printing mechanism coincides with the up and down direction, and printing is performed on the upper surface of the medium in the printing mechanism. Further, the medium printed by the printing mechanism moves forward.
In the printer under development, the inventor of the present application is considering moving the medium, having moved forward after printing, by a predetermined distance downward, then moving the medium by a predetermined distance backward, and then winding the medium by the winding roll holding unit. In this printer, when tension is applied to the medium by bringing the tension bar into contact with the medium moving backward from below, the tension bar comes into contact with the printing surface of the medium, which may affect the print quality of the medium. On the other hand, when the tension bar is brought into contact with the medium moving backward from above to apply tension to the medium, it is necessary to secure a space for arranging the medium and the tension bar when the tension bar in contact with the medium moves downward, and thus the printer may become large in size in the up and down direction.
Therefore, in the printer under development, the inventor of the present application is considering applying tension to the medium by bringing the tension bar into contact with a surface of the medium moving downward on a side opposite to the printing surface. That is, the inventor of the present application has studied applying tension to the medium by bringing the tension bar into contact with the medium moving downward from the rear side. In this case, when the tension bar is moved in the front and rear direction, it is necessary to secure an arrangement space for the medium and the tension bar when the tension bar in contact with the medium is moved to the front side, and thus the printer may become large in size in the front and rear direction.
Therefore, in the printer under development, the inventor of the present application has decided to enable the movement of the tension bar in a forward and downward direction, bring the tension bar into contact with the medium after printing moving downward from an obliquely rear and upper side, and apply tension to the medium by gravity acting on the tension bar. When the medium contact angle is a central angle of an arc-shaped contact portion that is a portion of the outer peripheral surface of the tension bar in contact with the medium when viewed from the left and right direction, in the case of this printer, the medium contact angle varies depending on the position of the tension bar, and the tension of the medium applied by the tension bar varies depending on the position of the tension bar.
Specifically, as the tension bar moves obliquely forward and downward, the medium contact angle increases, and the tension of the medium applied by the tension bar increases. As the tension bar moves obliquely backward and upward, the medium contact angle decreases, and the tension of the medium applied by the tension bar decreases. In addition, since the moving amount of the tension bar increases as the moving speed of the medium increases, in the printer under development, when the moving speed of the medium increases, the tension of the medium greatly fluctuates, and the behavior of the medium may become unstable.
Therefore, an object of the present invention is to provide a printer including a printing mechanism that performs printing on a long medium, a winding roll holding unit that holds a winding roll as a medium after printing wound in a roll shape, and a tension bar that applies tension to the medium by coming into contact with the medium after printing between the printing mechanism and the winding roll holding unit, the printer being capable of moving the tension bar in a forward and downward direction, and suppressing fluctuation in the tension of the medium applied by the tension bar when the position of the tension bar fluctuates even when the tension bar is brought into contact with the medium after printing moving downward from an obliquely rear and upper side and the tension is applied to the medium by gravity acting on the tension bar.
Furthermore, in the inkjet printer described in Patent Document 2, the ink mist generated at the time of discharging the ink from the inkjet head is sucked by the fan and enters the space on the lower side of the printing platen through the suction hole. In the inkjet printer described in Patent Document 2, the inventor of the present application has found that the ink mist entering the space on the lower side of the printing platen may be solidified in the space on the lower side of the printing platen and the discharge path of the air from this space to become a solid material, and that the solid material may be discharged to the outside of the inkjet printer together with the air discharged from the space on the lower side of the printing platen. Further, the inventor of the present application has found that when the solid material is discharged to the outside of the inkjet printer together with the air discharged from the space on the lower side of the printing platen, the solid material may adhere to the medium to contaminate the medium.
Therefore, an object of the present invention is to provide an inkjet printer for performing printing on a long medium, the inkjet printer being capable of preventing contamination of the medium due to the solid material even if the solid material in which the ink mist is solidified is discharged toward the outside of the inkjet printer together with the air entering the inside of the hollow platen when sucking the medium into the platen.
Furthermore, in the moisturizing device described in Patent Document 3, water is supplied into the cap so that the water supply amount is 50 mass% or more with respect to the amount of ink to be pressurized and purged, and if the water supply amount is 50 mass% or more with respect to the amount of ink to be pressurized and purged, water is not supplied into the cap even if the amount of ink and water (that is, the amount of liquid in the cap) in the cap decreases. Therefore, in the case of the moisturizing device described in Patent Document 3, the liquid level of the liquid in the cap may be excessively lowered, and it may be difficult to appropriately moisturize the nozzle surface of the head unit.
Therefore, an object of the present invention is to provide a moisturizing device for moisturizing a nozzle surface of a head unit including a plurality of inkjet heads, the device being capable of preventing an excessive decrease in a liquid level of a moisturizing liquid stored in a main container so that the nozzle surface can be appropriately moisturized using the moisturizing liquid for moisturization stored in the main container. Another object of the present invention is to provide an inkjet printer including such a moisturizing device.

MEANS FOR SOLVING THE PROBLEM

In order to solve the above problems, a printer of the present invention includes a printing mechanism which performs printing on a long medium, a winding roll holding unit which holds a winding roll as a medium after printing wound in a roll shape, and a tension applying mechanism which includes a tension bar coming into contact with the medium after printing between the printing mechanism and the winding roll holding unit to apply tension to the medium, wherein a width direction of the medium coincides with a left and right direction orthogonal to an up and down direction, wherein a thickness direction of the medium when printing is performed by the printing mechanism coincides with the up and down direction, wherein the medium printed by the printing mechanism moves forward and then moves downward when a direction orthogonal to the up and down direction and the left and right direction is a front and rear direction, wherein the tension bar is disposed below the printing mechanism, comes into contact with the medium moving downward from an obliquely rear and upper side, and applies tension to the medium by gravity acting on the tension bar, and wherein the tension applying mechanism includes a guide portion that linearly guides the tension bar in a forward and downward direction, and a biasing member that biases the tension bar to an obliquely rear and upper side.
In the printer of the present invention, the tension applying mechanism includes a biasing member for biasing the tension bar toward the obliquely rear and upper side, and the biasing force of the biasing member increases as the tension bar moves toward the obliquely front and lower side and decreases as the tension bar moves toward the obliquely rear and upper side. That is, in the present invention, even if the medium contact angle increases as the tension bar moves obliquely forward and downward, the biasing force of the biasing member with respect to the tension bar in the direction in which the tension of the medium applied by the tension bar decreases increases as the tension bar moves obliquely forward and downward. In the present invention, even if the medium contact angle decreases as the tension bar moves obliquely backward and upward, as the tension bar moves obliquely backward and upward, the biasing force of the biasing member with respect to the tension bar in the direction in which the tension of the medium applied by the tension bar decreases decreases.
Therefore, in the present invention, the tension bar can be moved in a forward and downward direction, and even when the tension bar is brought into contact with the medium after printing moving downward from an obliquely rear and upper side and the tension is applied to the medium by gravity acting on the tension bar, the fluctuation in the tension of the medium applied by the tension bar when the position of the tension bar fluctuates can be suppressed.
In the present invention, it is preferable that the tension applying mechanism includes two guide portions and two biasing members, one guide portion guides the right end side of the tension bar, the other guide portion guides the left end side of the tension bar, one biasing member biases the right end of the tension bar, and the other biasing member biases the left end of the tension bar. With this configuration, the tension bar can be biased in a well-balanced manner using the two biasing members. Accordingly, it is possible to effectively reduce fluctuations in the tension of the medium applied by the tension bar when the position of the tension bar fluctuates.
In the present invention, it is preferable that the tension applying mechanism includes two sliders that are formed separately from the tension bar and are linearly movable in the same direction as the moving direction of the tension bar, and a linear scale and a sensor for detecting the position of the tension bar, the linear scale is fixed to one of the two sliders, one slider is in contact with the right end of the tension bar from an obliquely front and lower side, the other slider is in contact with the left end of the tension bar from an obliquely front and lower side, and the biasing member engages with the slider to bias the slider obliquely backward and upward.
With this configuration, since the biasing member engages with the slider formed separately from the tension bar, for example, when the medium is set in the printer by moving the tension bar to a position deviated from the guide portion, it is not necessary to release the engagement state between the slider and the biasing member or to reengage the slider and the biasing member. Therefore, the operation when setting the medium in the printer can be simplified. According to this configuration, the linear scale is fixed to the slider used to contact the tension bar to bias the tension bar, and there is no need to separately provide a member for fixing the linear scale. Therefore, the configuration of the tension applying mechanism can be simplified.
In the present invention, it is preferable that the tension applying mechanism includes a tension bar support portion that is disposed above the guide portion and supports the tension bar separated from the guide portion. With this configuration, when the medium is set in the printer, the tension bar can be easily disposed at a position deviated from the guide portion on the upper side of the guide portion. Therefore, it is possible to easily set the medium in the printer.
In the present invention, for example, the guide portion guides the tension bar in a direction inclined at 30° to 60° with respect to the front and rear direction when viewed from the left and right direction.
In the present invention, for example, the printer includes a heater for heating the medium after printing, the heater is disposed below and behind the tension bar, the winding roll is disposed above and behind the heater, and the medium that has passed through the tension bar then passes above the heater and moves backward.
In the present invention, for example, a printing mechanism includes an inkjet head that ejects ink onto a medium, a platen on which the medium when printing is placed, and a suction mechanism that sucks and holds the medium placed on the platen on the platen, wherein the platen is disposed above a heater, wherein the suction mechanism includes a plurality of intake ports arranged in a left and right direction, a suction fan in which the plurality of intake ports are connected via pipes, and a filter that is disposed in the middle of a pipe path between the plurality of intake ports and the suction fan and through which air sucked from the plurality of intake ports passes, and wherein the filter is disposed at a position shifted from the heater in a horizontal direction.
In this case, the ink mist generated at the time of discharging the ink from the inkjet head is sucked by the suction mechanism and adheres to the filter. The ink mist may be solidified by the filter to become a solid material, but since the filter is disposed at a position shifted from the heater in the horizontal direction, the solid material does not fall on the medium passing above the heater. Therefore, it is possible to prevent deterioration in print quality of the medium due to the solid material solidified by the filter. In this case, since the ink mist sucked from the plurality of intake ports adheres to the common filter, one common filter may be replaced when replacing the filter. Therefore, replacement work of the filter can be easily performed.
In the present invention, for example, the printing mechanism includes an inkjet head that ejects ink onto a medium and a platen on which the medium when printing is placed, the platen includes a platen body provided with a medium placement surface on which the medium is placed and a platen frame that supports the platen body from below, the platen body is formed of aluminum or an aluminum alloy, and at least the medium placement surface of the surface of the platen body is covered with a conductive coating. In the present invention, the coating is, for example, a plating coating. In the present invention, the plating coating is, for example, a nickel-plating coating.
For example, if the surface of the platen body is subjected to alumite treatment in order to enhance the abrasion resistance of the medium placement surface of the platen body, and the medium placement surface is covered with an insulating alumite coating, the amount of electric charge between the medium placement surface contacting the medium and the medium increases as the conveying distance of the medium increases when printing is performed on the medium while conveying the long medium, and as a result, the electrical suction force of the medium to the medium placement surface due to static electricity increases, and the medium may not be accurately conveyed. On the other hand, if the medium placement surface is covered with a conductive coating, it is possible to prevent electrification between the medium placement surface and the medium even if the conveying distance of the medium becomes long. Therefore, in this case, the medium can be accurately conveyed even when printing is performed on the medium while conveying the long medium, and even if the conveying distance of the medium becomes long.
In order to solve the above problems, an inkjet printer of the present invention is an inkjet printer for performing printing on a long medium, including an inkjet head that discharges ink on the medium, a platen that is disposed below the inkjet head and on which the medium when printing is placed, and a suction mechanism that sucks and holds the medium placed on the platen on the platen, wherein a plurality of suction holes for sucking the medium placed on the platen are formed in an upper surface of the platen, wherein the plurality of suction holes lead to an internal space of the platen formed in a hollow shape, wherein the suction mechanism includes an exhaust fan for discharging air in the internal space of the platen to the outside of the inkjet printer, and a flow path forming portion that forms an air flow path through which the air discharged from the internal space of the platen passes, and wherein when a medium having the widest width among the medium on which printing is performed in the inkjet printer is a maximum width medium, and a range in which the maximum width medium is disposed in a width direction of the medium orthogonal to a thickness direction of the medium and a longitudinal direction of the medium is a medium arrangement range, an exhaust fan is attached to a flow path forming portion, an exhaust hole through which air is discharged toward the outside of the inkjet printer by the exhaust fan is formed in the flow path forming portion, and the exhaust hole is disposed at a position deviated from the medium arrangement range in the width direction of the medium. At this time, the maximum width medium may be a medium having a maximum width that can be printed by the inkjet printer.
In the inkjet printer of the present invention, the suction mechanism for sucking and holding the medium placed on the platen by the platen includes an exhaust fan for discharging the air in the internal space of the platen to the outside of the inkjet printer, and a flow path forming portion in which an air flow path through which the air discharged from the internal space of the platen passes is formed, and an exhaust hole through which the air is discharged toward the outside of the inkjet printer by the exhaust fan is formed in the flow path forming portion. Furthermore, in the present invention, when a medium having the largest width among the medium on which printing is performed by the inkjet printer is a maximum width medium and a range in which the maximum width medium is disposed in the width direction of the medium is a medium arrangement range, the exhaust hole is disposed at a position deviated from the medium arrangement range in the width direction of the medium.
Therefore, in the present invention, when the air having entered the inside of the hollow platen when sucking the medium into the platen is discharged toward the outside of the inkjet printer, the solid material can be prevented from adhering to the medium even if the solid material in which the ink mist is solidified is discharged from the exhaust hole together with the air. Therefore, in the present invention, even if the solid material in which the ink mist is solidified is discharged toward the outside of the inkjet printer together with the air entering the inside of the hollow platen when sucking the medium into the platen, it is possible to prevent the medium from being contaminated due to the solid material.
In the present invention, the exhaust fan is preferably disposed at the same position as the exhaust hole in the width direction of the medium. According to such a configuration, the air can be efficiently discharged from the exhaust hole toward the outside of the inkjet printer by the exhaust fan.
In the present invention, the inkjet printer includes, for example, a carriage on which an inkjet head is mounted, a carriage driving mechanism that reciprocates the carriage in a main scanning direction that is a width direction of a medium, and a maintenance unit that prevents clogging of nozzles of the inkjet head, wherein the maintenance unit is disposed in a maintenance area that is an area deviated from a medium arrangement range in the main scanning direction, and when a side on which the maintenance area is disposed with respect to the medium arrangement range in the main scanning direction is a maintenance area side, the exhaust hole is disposed on the maintenance area side with respect to the medium arrangement range.
In the present invention, preferably, the suction mechanism includes a suction fan for sucking the medium placed on the platen, the suction fan is attached to the bottom surface of the platen, the flow path forming portion includes a hollow flow path forming frame formed in an elongated shape elongated in the width direction of the medium and having an air flow path formed therein, and a tubular connection member connecting the suction fan and the flow path forming frame, the exhaust fan is attached to one end of the flow path forming frame in the width direction of the medium, and the exhaust hole is formed at one end of the flow path forming frame in the width direction of the medium.
With this configuration, since the suction mechanism includes the suction fan in addition to the exhaust fan, the medium placed on the platen can be reliably sucked to the platen by the suction fan. According to such a configuration, since the exhaust hole is formed at one end in the width direction of the medium of the flow path forming frame formed in an elongated shape elongated in the width direction of the medium, the exhaust hole can be moved away from the medium in the width direction of the medium. Therefore, even if the solid material in which the ink mist is solidified is discharged from the exhaust hole together with the air, it is possible to effectively prevent the medium from being contaminated due to the solid material.
In the present invention, the connection member is preferably formed in a tubular shape by a thin film. With this configuration, even if the relative positional accuracy between the opening of the flow path forming frame connected to one end side of the connection member and the suction fan connected to the other end side of the connection member is not high, the opening of the flow path forming frame and the suction fan can be easily connected by the flexible connection member.
In the present invention, for example, the suction mechanism includes a filter through which the air discharged from the internal space of the platen passes, and the filter is disposed at a position deviated from the medium arrangement range in the width direction of the medium.
In the present invention, it is preferable that a plurality of intake holes arranged in the width direction of the medium is formed in the lower surface of the platen, the plurality of intake holes communicate with the internal space of the platen and communicate with the flow path of the air formed in the flow path forming portion, and the exhaust fan also functions to suck the medium placed on the platen. With this configuration, it is not necessary to separately provide a fan for sucking the medium placed on the platen. Therefore, the configuration of the suction mechanism can be simplified.
In the present invention, the inkjet printer includes, for example, a medium conveying mechanism which conveys the medium in a longitudinal direction of the medium, a winding roll holding unit which holds a winding roll as the medium after printing wound in a roll shape, a tension applying mechanism which includes a tension bar coming into contact with the medium after printing between the inkjet head and the winding roll holding unit in a moving path of the medium to apply tension to the medium, and a heater which heats the medium after printing, when a direction orthogonal to a width direction and an up and down direction of the medium is a front and rear direction, wherein a thickness direction of the medium when printing is performed by the inkjet head coincides with the up and down direction, wherein the medium printed by the inkjet head moves forward and then moves downward, wherein the tension bar is disposed below the platen, comes into contact with the medium moving downward from an obliquely rear and upper side, and applies tension to the medium by gravity acting on the tension bar, wherein the heater is disposed below and behind the tension bar, wherein the winding roll is disposed above and behind the heater, wherein the medium having passed through the tension bar then passes above the heater and moves backward, wherein the platen is disposed above the heater, wherein the suction mechanism includes a filter through which air discharged from the internal space of the platen passes through the plurality of intake holes, and wherein the filter is disposed at a position deviated from the medium arrangement range in the width direction of the medium, and is disposed at a position shifted from the heater in the width direction of the medium.
In this case, since the filter is disposed at a position deviated from the medium arrangement range in the width direction of the medium and is disposed at a position shifted from the heater in the width direction of the medium, the ink mist attached to the filter is solidified to become a solid material, and even if the solid material falls, the solid material can be prevented from being attached to the medium passing above the heater. In this case, since the ink mist discharged from the internal space of the platen through the plurality of intake holes adheres to the common filter, one common filter may be replaced when replacing the filter. Therefore, replacement work of the filter can be easily performed.
Further, in order to solve the above problems, a moisturizing device of the present invention is a moisturizing device for moisturizing a nozzle surface of a head unit including a plurality of inkjet heads, including a main container that is formed in a box shape with an open upper surface and stores a moisturizing liquid for moisturization, a sub-container that stores the moisturizing liquid and is connected to the main container, a moisturizing liquid supply unit that supplies the moisturizing liquid to the main container, and a liquid level detection mechanism that detects a height of a liquid level of the moisturizing liquid in the sub-container, wherein a liquid level of the moisturizing liquid in the main container is disposed below the nozzle surface at a non-printing time when the inkjet head does not eject ink, wherein the moisturizing liquid is able to flow between the main container and the sub-container, wherein the height of the liquid level of the moisturizing liquid in the sub-container is equal to a height of the liquid level of the moisturizing liquid in the main container, and wherein the moisturizing liquid supply unit supplies the moisturizing liquid to the main container based on a detection result of the liquid level detection mechanism.
In the moisturizing device of the present invention, the moisturizing liquid is able to flow between the main container and the sub-container, and the height of the liquid level of the moisturizing liquid in the sub-container is equal to the height of the liquid level of the moisturizing liquid in the main container. Therefore, in the present invention, the liquid level detection mechanism for detecting the height of the liquid level of the moisturizing liquid in the sub-container can indirectly detect the height of the liquid level of the moisturizing liquid in the main container. In the present invention, the moisturizing liquid supply unit supplies the moisturizing liquid to the main container based on the detection result of the liquid level detection mechanism. That is, in the present invention, the moisturizing liquid supply unit automatically supplies the moisturizing liquid to the main container based on the indirect detection result of the height of the liquid level of the moisturizing liquid in the main container. Therefore, in the present invention, it is possible to prevent an excessive decrease in the liquid level of the moisturizing liquid stored in the main container so that the nozzle surface can be appropriately moisturized using the moisturizing liquid stored in the main container.
In the present invention, the liquid level detection mechanism detects the height of the liquid level of the moisturizing liquid in the sub-container. Therefore, in the present invention, for example, even if the liquid level detection mechanism includes a float floating in the moisturizing liquid, the float is floating in the moisturizing liquid in the sub-container, so that the float and the nozzle surface do not interfere with each other. Therefore, in the present invention, there is no problem in moisturizing the nozzle surface due to the influence of the float. Further, in the present invention, since the float and the nozzle surface do not interfere with each other, the main container can be arranged without considering the position of the float, and as a result, the degree of freedom in arrangement of the main container can be increased. In the present invention, the nozzle surface and the like are not damaged due to interference between the float and the nozzle surface.
In the present invention, it is preferable that the moisturizing device includes a moisturizing liquid discharge unit for discharging the moisturizing liquid from the main container, and the moisturizing liquid discharge unit discharges the moisturizing liquid from the main container based on the detection result of the liquid level detection mechanism. With this configuration, since the moisturizing liquid discharge unit automatically discharges the moisturizing liquid from the main container based on the indirect detection result of the height of the liquid level of the moisturizing liquid in the main container, it is possible to prevent the moisturizing liquid from overflowing from the box-shaped main container whose upper surface is opened.
In the present invention, for example, the liquid level detection mechanism includes a float floating on the moisturizing liquid in the sub-container, a detection object attached to the float, and a sensor that is disposed outside the sub-container and detects the detection object.
In the present invention, it is preferable that the moisturizing device includes a seal member that can be brought into contact with the outer peripheral end of the nozzle surface from below, the outer shape of the nozzle surface is larger than the outer shape of the main container, and the seal member is disposed on the outer peripheral side of the main container. With this configuration, for example, even if the main container is installed at a place where wind flows, the seal member can suppress the wind from flowing from the gap between the upper end of the main container and the nozzle surface to the lower side of the nozzle surface, and as a result, it is possible to suppress a decrease in humidity on the lower side of the nozzle surface. Therefore, even if the main container is installed at a place where wind flows, it is possible to suppress drying of the nozzle surface caused by the wind around the main container.
In the present invention, for example, the outer shape of the nozzle surface is rectangular, and the seal member is disposed at a position where the seal member can contact the outer peripheral end of the nozzle surface on at least three sides of the rectangular nozzle surface. In a case where the seal member is disposed at a position where the seal member can come into contact with the outer peripheral end of the nozzle surface on three sides of the nozzle surface, even if wind flows into the lower side of the nozzle surface from the gap between the upper end of the main container and the nozzle surface on one side of the nozzle surface on which the seal member is not disposed, it is possible to prevent the flowing wind from blowing through the lower side of the nozzle surface. Therefore, even if the main container is installed at a place where wind flows, it is possible to effectively suppress a decrease in humidity on the lower side of the nozzle surface due to the wind around the main container, and as a result, it is possible to effectively suppress drying of the nozzle surface due to the wind around the main container. In this case, the configuration of the moisturizing device can be simplified as compared with the case where the seal member is disposed at a position where the seal member can contact the outer peripheral end of the nozzle surface on the four sides of the nozzle surface.
In addition, when the seal member is disposed at a position where the seal member can come into contact with the outer peripheral end of the nozzle surface on the four sides of the nozzle surface, the seal member can prevent wind from flowing from the gap between the upper end of the main container and the nozzle surface to the lower side of the nozzle surface. Therefore, even if the main container is installed at a place where wind flows, it is possible to prevent a decrease in humidity on the lower side of the nozzle surface due to the wind around the main container, and as a result, it is possible to prevent drying of the nozzle surface due to the wind around the main container.
In the present invention, a seal holding unit for holding a seal member is preferably formed at an upper end of the main container. With this configuration, the seal member can be disposed on the outer peripheral side of the main container with a relatively simple configuration.
In the present invention, the moisturizing device preferably includes a cover member disposed to surround the upper end of the main container, and the seal member is preferably fixed to the upper surface of the cover member. In the present invention, the moisturizing device preferably includes a second seal member that closes a gap formed between the upper end of the main container and the cover member. In this case, even if a gap is formed between the upper end of the main container and the cover member, it is possible to prevent wind from flowing from the gap between the main container and the cover member to the lower side of the nozzle surface.
The moisturizing device of the present invention can be used in an inkjet printer including a head unit having a plurality of inkjet heads, a carriage on which the head unit is mounted, and a carriage driving mechanism that moves the carriage in a main scanning direction. In this inkjet printer, the main container is disposed at a position deviated from a printing area that is an area where printing on the medium by the inkjet head is performed in the main scanning direction. In this inkjet printer, it is possible to prevent an excessive decrease in the liquid level of the moisturizing liquid stored in the main container so that the nozzle surface can be appropriately moisturized using the moisturizing liquid stored in the main container.

ADVANTAGEOUS EFFECTS OF THE INVENTION

As described above, according to the present invention, in a printer including a printing mechanism that performs printing on a long medium, a winding roll holding unit that holds a winding roll as a medium after printing wound in a roll shape and a tension bar that applies tension to the medium by coming into contact with the medium after printing between the printing mechanism and the winding roll holding unit, the tension bar can be moved in a forward and downward direction, and even when the tension bar is brought into contact with the medium after printing moving downward from an obliquely rear and upper side and tension is applied to the medium by gravity acting on the tension bar, fluctuation in the tension of the medium applied by the tension bar when the position of the tension bar fluctuates can be suppressed.
As described above, in the present invention, in the inkjet printer for performing printing on the long medium, even if the solid material in which the ink mist is solidified is discharged toward the outside of the inkjet printer together with the air entering the inside of the hollow platen when sucking the medium into the platen, it is possible to prevent the medium from being contaminated due to the solid material.
Furthermore, as described above, in the present invention, in the moisturizing device for moisturizing the nozzle surface of the head unit including the plurality of inkjet heads, it is possible to prevent an excessive decrease in the liquid level of the moisturizing liquid stored in the main container so that the nozzle surface can be appropriately moisturized using the moisturizing liquid for moisturization stored in the main container.

BRIEF DESCRIPTION OF DRAWINGS

Fig. 1 is a side view for illustrating a configuration of a printer according to an embodiment of the present invention.
Fig. 2 is a block diagram for illustrating a configuration of the printer illustrated in Fig. 1.
Fig. 3 is a schematic view for illustrating a configuration of a suction mechanism included in a printing mechanism illustrated in Fig. 1.
Fig. 4 is a perspective view for illustrating a configuration of a right side portion of a tension applying mechanism illustrated in Fig. 1.
Fig. 5 is a perspective view for illustrating a configuration of a right side portion of the tension applying mechanism illustrated in Fig. 1.
Fig. 6 is a perspective view for illustrating a configuration of a left side portion of the tension applying mechanism illustrated in Fig. 1.
Fig. 7 is a graph illustrating an example of a relationship between a position of a tension bar illustrated in Fig. 1 and the tension of the medium applied by the tension bar.
Figs. 8(A) to 8(I) are diagrams for illustrating an arrangement position of a sensor with respect to a linear scale when the linear scale illustrated in Fig. 4 moves, and Fig. 8(J) is a table for illustrating a detection state of the sensor with respect to a movement amount of the linear scale illustrated in Fig. 4.
Fig. 9 is a side view for illustrating a configuration of a platen illustrated in Fig. 1.
Fig. 10 is a table of experimental results for illustrating the effect of the platen illustrated in Fig. 9.
Fig. 11 is a side view for illustrating a configuration of a printer according to another embodiment of the present invention.
Fig. 12 is a side view for illustrating a configuration of an inkjet printer according to the embodiment of the present invention.
Fig. 13 is a schematic view for illustrating a configuration of a printing mechanism illustrated in Fig. 12.
Fig. 14 is a perspective view illustrating a suction mechanism and the like illustrated in Fig. 12 from an obliquely rear lower side.
Fig. 15(A) is a plan view of a platen and a suction mechanism illustrated in Fig. 12, and Fig. 15(B) is a front view of the platen and the suction mechanism illustrated in Fig. 12.
Fig. 16 is a cross-sectional view for illustrating a configuration of the platen and the suction mechanism illustrated in Fig. 12.
Fig. 17 is a side view for illustrating a configuration of an inkjet printer according to another embodiment of the present invention.
Fig. 18 is a schematic view for illustrating a configuration of a suction mechanism included in a printing mechanism illustrated in Fig. 17.
Fig. 19 is a schematic view for illustrating a configuration of an inkjet printer according to an embodiment of the present invention.
Fig. 20 is a bottom view of a head unit illustrated in Fig. 19.
Fig. 21 is a schematic view for illustrating a configuration of a moisturizing device according to an embodiment of the present invention.
Fig. 22 is a block diagram for illustrating a configuration of the moisturizing device illustrated in Fig. 3.
Fig. 23(A) is a plan view for illustrating a configuration of a main container illustrated in Fig. 21, and Fig. 23(B) is a cross-sectional view taken along line E-E of Fig. 23(A).
Fig. 24(A) is a plan view for illustrating a configuration of a main container and the like according to another embodiment of the present invention, Fig. 24(B) is a cross-sectional view taken along line F-F of Fig. 24(A), Fig. 24(C) is a cross-sectional view taken along line G-G of Fig. 24(A), and Fig. 24(D) is a cross-sectional view taken along line H-H of Fig. 24(A).
Fig. 25(A) is a plan view for illustrating a configuration of a main container and the like according to another embodiment of the present invention, and Fig. 25(B) is a cross-sectional view taken along line J-J of Fig. 25(A).

DESCRIPTION OF EMBODIMENTS

Hereinafter, a first embodiment of the present invention will be described with reference to the drawings.

(Overall configuration of printer)

Fig. 1 is a side view for illustrating a configuration of a printer 1 according to an embodiment of the present invention. Fig. 2 is a block diagram for illustrating a configuration of the printer 1 illustrated in Fig. 1. Fig. 3 is a schematic view for illustrating a configuration of a suction mechanism 21 included in a printing mechanism 3 illustrated in Fig. 1.
The printer 1 of this embodiment is, for example, a business inkjet printer. The printer 1 includes a printing mechanism 3 that performs printing on a long medium 2 (sheet-shaped medium 2) such as paper, a medium conveying mechanism 4 that conveys the medium 2, a feeding roll holding unit 6 that holds a feeding roll 5 as the medium 2 before printing wound in a roll shape, a winding roll holding unit 8 that holds a winding roll 7 as the medium 2 after printing wound in a roll shape, a plurality of guide rollers 9 that guides the medium 2 to be conveyed, and a heater 10 that heats the medium 2 after printing. The medium 2 of this embodiment is, for example, a transfer sheet. The length of the medium 2 is, for example, 2000 (m).
The printer 1 further includes a tension applying mechanism 11 that applies tension to the medium 2 before printing, a tension applying mechanism 12 that applies tension to the medium 2 after printing, and a controller 13 that controls the printer 1. When the Y direction in Fig. 1 orthogonal to the up and down direction(vertical direction) is referred to as a "left and right direction", the width direction of the medium 2 coincides with the left and right direction. In the following description, an X direction in Fig. 1 orthogonal to the up and down direction and the left and right direction is referred to as a "front and rear direction". An X1 direction side in Fig. 1, which is one side in the front and rear direction, is referred to as a "front" side, and an X2 direction side in Fig. 1, which is the opposite side, is referred to as a "rear" side.
The printing mechanism 3 includes an inkjet head 17 (hereinafter, referred to as a "head 17") that ejects ink onto the medium 2, a carriage 18 on which the head 17 is mounted, a carriage driving mechanism that reciprocates the carriage 18 in a main scanning direction (that is, in the left and right direction) that is a width direction of the medium 2, and a support frame (Y bar) 19 that supports the carriage 18 to be movable in the left and right direction. The head 17 ejects ink downward. A plurality of nozzles for discharging ink is formed on a lower surface of the head 17. The head 17 includes a piezoelectric element for discharging ink from the nozzle. The carriage driving mechanism includes, for example, a belt partially fixed to the carriage 18, a pulley around which the belt is stretched, and a motor for rotating the pulley.
The printing mechanism 3 further includes a platen 20 on which the medium 2 is placed when printing, and a suction mechanism 21 for sucking and holding the medium 2 placed on the platen 20 on the platen 20. The platen 20 is disposed below the carriage 18. The platen 20 is formed in an elongated shape elongated in the left and right direction. The platen 20 is formed in a hollow shape. A plurality of suction holes for sucking the medium 2 placed on the platen 20 are formed in the upper surface portion of the platen 20. The plurality of suction holes are formed over substantially the entire area of the platen 20. The thickness direction of the medium 2 when printing is performed by the printing mechanism 3 coincides with the up and down direction. The upper surface of the medium 2 when placed on the platen 20 is a printing surface on which printing is performed by the printing mechanism 3. A more specific configuration of the platen 20 will be described later.
As illustrated in Fig. 3, the suction mechanism 21 includes a plurality of intake ports 23 arranged in the left and right direction, a suction fan 25 in which the plurality of intake ports 23 are connected via a pipe 24, and a filter 26 disposed in the middle of a pipe path between the plurality of intake ports 23 and the suction fan 25. The intake port 23 communicates with the inside of the platen 20 formed in a hollow shape. The plurality of intake ports 23 are arranged at predetermined intervals in the left and right direction. The intake port 23 is disposed in the entire area of the platen 20 in the left and right direction.
The suction mechanism 21 of this embodiment includes one suction fan 25 and one filter 26. When the suction fan 25 operates, the air inside the platen 20 is sucked from all of the plurality of intake ports 23. That is, when the suction fan 25 is driven, the air inside the platen 20 is discharged. When the air inside the platen 20 is discharged, the medium 2 is sucked into the suction holes of the platen 20, and the medium 2 is held by the platen 20. When the suction fan 25 operates, the air sucked from all of the plurality of intake ports 23 passes through the filter 26.
The medium conveying mechanism 4 conveys the long medium 2 in the longitudinal direction of the medium 2. The medium conveying mechanism 4 includes a conveying roller 27 that contacts the medium 2 to convey the medium 2. The conveying roller 27 is a rubber roller whose surface is formed of rubber. The conveying roller 27 is connected to a driving mechanism that rotates the conveying roller 27. The driving mechanism includes a motor as a drive source and a power transmission mechanism that transmits power of the motor to the conveying roller 27. The conveying roller 27 is disposed behind the platen 20. The medium 2 before printing is conveyed from the rear side to the upper surface of the platen 20. Furthermore, the medium 2 after printing is conveyed from the upper surface of the platen 20 forward and then conveyed downward. That is, the medium 2 printed by the printing mechanism 3 moves forward and then moves downward. In this embodiment, the conveying speed of the medium 2 is relatively high. For example, the maximum conveying speed of the medium 2 is 350 (mm/sec).
The feeding roll holding unit 6 is disposed below the platen 20. The feeding roll holding unit 6 is disposed behind the printing mechanism 3. The feeding roll 5 is disposed such that the axial direction of the feeding roll 5 coincides with the left and right direction. The feeding roll holding unit 6 includes a rotating shaft 29 inserted into the inner peripheral side of the feeding roll 5, and a driving mechanism that rotates the rotating shaft 29. The driving mechanism includes a motor 30 as a drive source and a power transmission mechanism that transmits power of the motor 30 to the rotating shaft 29.
The motor 30 is PID controlled. A rotary encoder for detecting a rotation amount and a rotation speed of the motor 30 is attached to the motor 30. The rotary encoder includes a disk-shaped rotary scale (slit plate) fixed to a rotating shaft of the motor 30, and a sensor 31 for detecting the rotary scale. The sensor 31 is a transmissive optical sensor including a light emitting unit and a light receiving unit, and a portion of the rotary scale is disposed between the light emitting unit and the light receiving unit. The sensor 31 is electrically connected to the controller 13.
The winding roll holding unit 8 is disposed below the feeding roll holding unit 6, and is disposed behind the printing mechanism 3. The winding roll 7 is disposed such that the axial direction of the winding roll 7 coincides with the left and right direction. The winding roll holding unit 8 includes a rotating shaft 32 inserted through the inner peripheral side of the winding roll 7, and a driving mechanism that rotates the rotating shaft 32. The driving mechanism includes a motor 33 as a drive source and a power transmission mechanism that transmits power of the motor 33 to the rotating shaft 32.
The motor 33 is PID controlled. A rotary encoder for detecting a rotation amount and a rotation speed of the motor 33 is attached to the motor 33. The rotary encoder includes a disk-shaped rotary scale fixed to a rotating shaft of the motor 33, and a sensor 34 for detecting the rotary scale. The sensor 34 is a transmissive optical sensor including a light emitting unit and a light receiving unit, and a portion of the rotary scale is disposed between the light emitting unit and the light receiving unit. The sensor 34 is electrically connected to the controller 13.
The tension applying mechanism 11 includes a tension bar 37 that contacts the medium 2 before printing between the printing mechanism 3 and the feeding roll holding unit 6 to apply tension to the medium 2, and a guide portion that linearly guides the tension bar 37 in the up and down direction. The tension bar 37 is disposed such that the axial direction of the tension bar 37 coincides with the left and right direction. The tension bar 37 is disposed between the printing mechanism 3 and the feeding roll 5 in the front and rear direction. The tension bar 37 is disposed below the printing mechanism 3 and the feeding roll 5. The tension bar 37 comes into contact with the medium 2 moving forward from the feeding roll holding unit 6 toward the printing mechanism 3 from above. The tension bar 37 applies tension to the medium 2 by gravity acting on the tension bar 37. At the time of printing the medium 2, the tension bar 37 linearly moves in the up and down direction according to the movement of the medium 2.
The tension applying mechanism 11 includes a linear encoder for detecting the position of the tension bar 37. The linear encoder includes a linear scale that moves in the up and down direction together with the tension bar 37, and two sensors 38 and 39 for detecting the linear scale. The sensors 38 and 39 are arranged at predetermined intervals in the up and down direction. The sensors 38 and 39 are transmissive optical sensors having a light emitting unit and a light receiving unit, and a portion of the linear scale is disposed between the light emitting unit and the light receiving unit. The sensors 38 and 39 are electrically connected to the controller 13.
The tension applying mechanism 12 includes a tension bar 40 that comes into contact with the medium 2 after printing between the printing mechanism 3 and the winding roll holding unit 8 to apply tension to the medium 2. The tension bar 40 is disposed such that the axial direction of the tension bar 40 coincides with the left and right direction. The tension bar 40 is disposed in front of and below the printing mechanism 3. The tension bar 40 is linearly movable in a forward and downward direction as indicated by an arrow in Fig. 1. The tension bar 40 comes into contact with the medium 2 after printing from the obliquely rear and upper side, the medium 2 moving downward after moving forward from the platen 20. The tension bar 40 applies tension to the medium 2 by gravity acting on the tension bar 40. A more specific configuration of the tension applying mechanism 12 will be described later.
The heater 10 is disposed below the printing mechanism 3, and the platen 20 is disposed above the heater 10. The heater 10 is disposed below the tension bar 37. The heater 10 is disposed below and behind the tension bar 40. The heater 10 is disposed below and in front of the feeding roll 5 and the winding roll 7. That is, the feeding roll 5 and the winding roll 7 are arranged above and behind the heater 10. The filter 26 is disposed at a position shifted from the heater 10 in the horizontal direction.
As described above, the medium 2 printed by the printing mechanism 3 moves forward and then moves downward. The medium 2 moved downward then moves backward. The medium 2 moving backward passes above the heater 10. Further, as described above, the tension bar 40 comes into contact with the medium 2 after printing moving from the platen 20 forward and then moving downward from the obliquely rear and upper side. That is, the medium 2 having passed through the tension bar 40 then passes above the heater 10 and moves backward.
The plurality of guide rollers 9 are driven rollers that rotate with the movement of the medium 2. The two guide rollers 9 of the plurality of guide rollers 9 are arranged on both sides of the tension bar 37 in the front and rear direction and are arranged above the tension bar 37. One guide roller 9 of the plurality of guide rollers 9 is disposed on the front side of the platen 20, and functions to change the moving direction of the medium 2 moving from the platen 20 forward to a downward direction.
One guide roller 9 of the plurality of guide rollers 9 is disposed below the tension bar 40 and on the front side of the printer 1, and functions to change the moving direction of the medium 2 moving downward to the direction backward. The two guide rollers 9 of the plurality of guide rollers 9 are arranged below the tension bar 40, and are arranged between the heater 10 and the winding roll 7 in the front and rear direction. One of the two guide rollers 9 disposed on the front side is in contact with the lower surface of the medium 2, and the other guide roller 9 disposed on the rear side is in contact with the upper surface of the medium 2.

(Configuration of tension applying mechanism)

Figs. 4 and 5 are perspective views illustrating a configuration of a right side portion of the tension applying mechanism 12 illustrated in Fig. 1. Fig. 6 is a perspective view for illustrating a configuration of a left side portion of the tension applying mechanism 12 illustrated in Fig. 1. Fig. 7 is a graph illustrating an example of the relationship between the position of the tension bar 40 illustrated in Fig. 1 and the tension of the medium 2 applied by the tension bar 40. Figs. 8(A) to 8(I) are diagrams for illustrating the arrangement positions of sensors 50 and 51 with respect to a linear scale 49 when the linear scale 49 illustrated in Fig. 4 moves, and Fig. 8(H) is a table for illustrating detection states of the sensors 50 and 51 with respect to the movement amount of the linear scale 49 illustrated in Fig. 4.
The tension applying mechanism 12 includes a guide portion 43 that linearly guides the tension bar 40 in a forward and downward direction, and a biasing member 44 that biases the tension bar 40 to an obliquely rear and upper side. The biasing member 44 of this embodiment is a tension coil spring. Therefore, in the following description, the biasing member 44 is referred to as a "tension coil spring 44". In this embodiment, the tension applying mechanism 12 includes two guide portions 43 and two tension coil springs 44.
The tension applying mechanism 12 includes two bearings 45 attached to the tension bar 40, two sliders 46 formed separately from the tension bar 40 and linearly movable in the same direction as the moving direction of the tension bar 40, two guide plates 47 for guiding the sliders 46, and a linear encoder 48 for detecting the position of the tension bar 40. The linear encoder 48 includes a linear scale 49 that moves in the up and down direction together with the tension bar 40, and two sensors 50 and 51 for detecting the linear scale 49.
The tension bar 40 includes a shaft portion 53 formed in an elongated columnar shape, and a cylindrical bar body 54 into which the shaft portion 53 is inserted on the inner peripheral side. The shaft portion 53 is disposed such that the axial direction of the shaft portion 53 coincides with the left and right direction. The bar body 54 is formed in a thick cylindrical shape elongated in the left and right direction. The bar body 54 is in contact with the medium 2. The length of the shaft portion 53 is longer than the length of the bar body 54, and both ends of the shaft portion 53 are arranged outside both ends of the bar body 54 in the left and right direction. The bearing 45 is, for example, a ball bearing. The bearings 45 are attached to both ends in the left and right direction of the shaft portion 53 protruding outward in the left and right direction from both ends of the bar body 54.
One guide portion 43 of the two guide portions 43 guides the right end side of the tension bar 40, and the other guide portion 43 guides the left end side of the tension bar 40. The guide portion 43 includes two guide members 55 disposed to sandwich the bearing 45. The guide member 55 is fixed to a frame 57 fixed to a body frame of the printer 1. One guide member 55 of the two guide members 55 is provided with a planar contact surface in contact with the bearing 45 from the obliquely rear lower side, and the other guide member 55 is provided with a planar contact surface in contact with the bearing 45 from the obliquely front upper side.
The contact surface of the bearing 45 formed on one guide member 55 and the contact surface of the bearing 45 formed on the other guide member 55 are parallel to each other. At the time of printing on the medium 2, the tension bar 40 moves linearly between the two guide members 55 in accordance with the movement of the medium 2 (see the solid line in Fig. 4, the solid line in Fig. 5, and the solid line and the two-dot chain line in Fig. 6). At this time, the bearing 45 rotates with respect to the guide member 55.
An inclination θ (see Fig. 1) of the moving direction of the tension bar 40 with respect to the front and rear direction when viewed from the left and right direction is 30° to 60°. That is, the guide portion 43 guides the tension bar 40 in a direction inclined at 30° to 60° with respect to the front and rear direction when viewed from the left and right direction. In this embodiment, the inclination θ is 45°, and the guide portion 43 guides the tension bar 40 in a direction inclined by 45° with respect to the front and rear direction when viewed from the left and right direction.
An upper side of the guide portion 43 is a tension bar support portion 56 that supports the tension bar 40 separated from the guide portion 43. That is, the tension applying mechanism 12 includes the tension bar support portion 56 that is disposed above the guide portion 43 and supports the tension bar 40 separated from the guide portion 43. The tension bar support portion 56 includes a support member that supports both ends in the left and right direction of the shaft portion 53 disposed outside the bearing 45 in the left and right direction from an obliquely front and lower side.
When setting the medium 2 in the printer 1, the tension bar 40 is disposed at a position deviated from the guide portion 43 on the upper side of the guide portion 43 and is supported by the tension bar support portion 56 (see two-dot chain lines in Figs. 4 to 6). When the tension bar 40 is supported by the tension bar support portion 56, the tension bar 40 is disposed at a position not in contact with the medium 2. The movement of the tension bar 40 to a position deviated from the guide portion 43 and the movement of the tension bar 40 to the guide portion 43 are manually performed.
One slider 46 of the two sliders 46 is in contact with the right end of the tension bar 40 from an obliquely front and lower side, and the other slider 46 is in contact with the left end of the tension bar 40 from an obliquely front and lower side. The slider 46 is in contact with both ends in the left and right direction of the shaft portion 53 disposed outside the bearing 45 in the left and right direction. A slit-shaped guide groove 47a for guiding the slider 46 is formed in the guide plate 47. A portion of the slider 46 is disposed in the guide groove 47a. The guide plate 47 is fixed to the frame 57. The guide plate 47 is disposed obliquely in front of and above the bearing 45. When the tension bar 40 is supported by the tension bar support portion 56, the slider 46 is not in contact with the tension bar 40 and is away from the tension bar 40.
One end of one tension coil spring 44 of the two tension coil springs 44 engages with the slider 46 in contact with the right end of the tension bar 40, and the other end of the tension coil spring 44 engages with a spring holding member 58 fixed to the upper end of the guide plate 47. One end of the other tension coil spring 44 engages with the slider 46 in contact with the left end of the tension bar 40, and the other end of the tension coil spring 44 engages with the spring holding member 58 fixed to the upper end of the guide plate 47.
The tension coil spring 44 biases the slider 46 to an obliquely rear and upper side. That is, the tension coil spring 44 biases the tension bar 40 toward the obliquely rear and upper side via the slider 46 in contact with the tension bar 40 from the obliquely front and lower side. One tension coil spring 44 of the two tension coil springs 44 biases the right end of the tension bar 40, and the other tension coil spring 44 biases the left end of the tension bar 40. The biasing force of the tension coil spring 44 increases as the tension bar 40 moves obliquely forward and downward, and decreases as the tension bar 40 moves obliquely backward and upward.
When the tension bar 40 moves obliquely forward and downward, the slider 46 is pushed by the tension bar 40 and moves obliquely forward and downward together with the tension bar 40. When the tension bar 40 moves obliquely backward and upward, the slider 46 moves obliquely backward and upward by the biasing force of the tension coil spring 44. At this time, the slider 46 moves toward the obliquely rear and upper side together with the tension bar 40 while maintaining a state of being in contact with the tension bar 40 from the obliquely front and lower side by the biasing force of the tension coil spring 44.
As described above, in this embodiment, the tension bar 40 comes into contact with the medium 2 after printing moving downward from the obliquely rear and upper side, and applies tension to the medium 2 by gravity acting on the tension bar 40. In this embodiment, therefore, the medium contact angle varies depending on the position of the tension bar 40 (see the solid line and the two-dot chain line in Fig. 1), where the medium contact angle is the central angle of the arc-shaped contact portion of the outer peripheral surface of the tension bar 40 in contact with the medium 2 when viewed from the left and right direction.
Thus, when the tension applying mechanism 12 does not include the tension coil spring 44, the tension of the medium 2 applied by the tension bar 40 greatly varies depending on the position of the tension bar 40 as indicated by a straight line L1 in Fig. 7. Specifically, the medium contact angle increases as the tension bar 40 moves obliquely forward and downward, and the medium contact angle decreases as the tension bar 40 moves obliquely backward and upward, so that the tension of the medium 2 decreases as the moving distance of the tension bar 40 from the lower limit position increases. That is, the tension of the medium 2 increases as the tension bar 40 approaches the lower limit position of the tension bar 40.
On the other hand, in this embodiment, the tension applying mechanism 12 includes the tension coil spring 44 for biasing the tension bar 40 toward the obliquely rear and upper side, and the biasing force of the tension coil spring 44 increases as the tension bar 40 approaches the lower limit position of the tension bar 40. That is, even if the medium contact angle increases as the tension bar 40 moves obliquely forward and downward, the biasing force of the tension coil spring 44 with respect to the tension bar 40 in the direction in which the tension of the medium 2 applied by the tension bar 40 decreases increases as the tension bar 40 moves obliquely forward and downward. Even if the medium contact angle decreases as the tension bar 40 moves obliquely backward and upward, the biasing force of the tension coil spring 44 with respect to the tension bar 40 in the direction in which the tension of the medium 2 applied by the tension bar 40 decreases decreases as the tension bar 40 moves obliquely backward and upward.
In this embodiment, the spring force and the spring constant of the tension coil spring 44 are set to suppress the fluctuation in the tension of the medium 2 due to the position of the tension bar 40. In this embodiment, therefore, the tension of the medium 2 is prevented from fluctuating regardless of the moving distance of the tension bar 40 from the lower limit position, as indicated by a curve L2 in Fig. 7. Regardless of the position of the tension bar 40, tension is always applied to the medium 2 by the tension bar 40. That is, the tension bar 40 does not move to an obliquely rear and upper side only by the biasing forces of the two tension coil springs 44.
The linear scale 49 is fixed to one slider 46 of the two sliders 46. In this embodiment, the linear scale 49 is fixed to the slider 46 that comes into contact with the right end of the tension bar 40 from the obliquely front and lower side. The sensors 50 and 51 are transmissive optical sensors including a light emitting unit and a light receiving unit, and the light emitting unit and the light receiving unit are arranged to face each other in a state of being spaced apart from each other in the left and right direction. The sensors 50 and 51 are arranged at predetermined intervals in the longitudinal direction of the linear scale 49. The sensors 50 and 51 are attached to the frame 57. A portion of the linear scale 49 is disposed between the light emitting unit and the light receiving unit of the sensors 50 and 51. The sensors 50 and 51 are electrically connected to the controller 13.
The longitudinal direction of the linear scale 49 coincides with the moving direction of the tension bar 40 and the slider 46. Through holes penetrating the linear scale 49 at constant intervals are formed in the linear scale 49. The through hole is a light passing portion 49a through which light from the light emitting units of the sensors 50 and 51 toward the light receiving unit passes. A portion between the through holes in the longitudinal direction of the linear scale 49 is a light shielding portion 49b that shields light from the light emitting units of the sensors 50 and 51 toward the light receiving unit. The width of the light passing portion 49a and the width of the light shielding portion 49b in the longitudinal direction of the linear scale 49 are equal.
In this embodiment, the detection widths of the sensors 50 and 51 in the longitudinal direction of the linear scale 49 are 1/4 of the width of the light passing portion 49a in the longitudinal direction of the linear scale 49. The pitch between the sensor 50 and the sensor 51 in the longitudinal direction of the linear scale 49 is, for example, 14 (mm). In this embodiment, every time the linear scale 49 moves by 1 (mm) together with the tension bar 40 and the slider 46, the arrangement relationship between the linear scale 49 and the sensors 50 and 51 is sequentially changed as illustrated in Figs. 8(A) to 8(I).
Therefore, every time the linear scale 49 moves by 1 (mm) together with the tension bar 40 and the slider 46, the detection states of the sensors 50 and 51 change as illustrated in Fig. 8(J). In this embodiment, as illustrated in Fig. 8(J), the resolution of the moving amount of the tension bar 40 detected by the linear encoder 48 is 2 (mm). Furthermore, in Fig. 8(J), "sensor A" is the sensor 50, and "sensor B" is the sensor 51.

(Medium feeding control and medium winding control)

In the feeding roll holding unit 6, the medium 2 is fed based on the detection results of the sensors 38 and 39. That is, the controller 13 controls the motor 30 based on the detection results of the sensors 38 and 39. Specifically, the controller 13 controls the motor 30 based on the detection results of the sensors 38 and 39 so that the tension bar 37 moved with the conveyance of the medium 2 by the medium conveying mechanism 4 returns to the original position. Furthermore, the controller 13 calculates the outer diameter of the feeding roll 5 based on the detection results of the sensors 38 and 39 and the detection result of the sensor 31 (specifically, based on the movement amount of the tension bar 37 and the rotation amount of the motor 30), and controls the motor 30 based on the calculation result of the outer diameter of the feeding roll 5. Specifically, the controller 13 increases the rotation amount of the motor 30 as the outer diameter of the feeding roll 5 decreases when feeding a certain amount of the medium 2.
In the winding roll holding unit 8, the medium 2 is wound based on the detection results of the sensors 50 and 51. That is, the controller 13 controls the motor 33 based on the detection results of the sensors 50 and 51. Specifically, the controller 13 controls the motor 33 based on the detection results of the sensors 50 and 51 so that the tension bar 40 moved with the conveyance of the medium 2 by the medium conveying mechanism 4 returns to the original position. The controller 13 calculates the outer diameter of the winding roll 7 based on the detection results of the sensors 50 and 51 and the detection result of the sensor 34 (specifically, based on the movement amount of the tension bar 40 and the rotation amount of the motor 33), and controls the motor 33 based on the calculation result of the outer diameter of the winding roll 7. Specifically, the controller 13 reduces the rotation amount of the motor 33 as the outer diameter of the winding roll 7 increases when winding a certain amount of the medium 2.

(Configuration of platen)

Fig. 9 is a side view for illustrating a configuration of the platen 20 illustrated in Fig. 1.
The platen 20 includes a platen body 61 on which a medium placement surface 61a on which the medium 2 is placed is formed, and a platen frame 62 that supports the platen body 61 from below. The platen frame 62 is formed in a rectangular groove shape (square groove shape) elongated in the left and right direction. The platen frame 62 is formed by bending a metal thin plate such as a steel plate into a square groove shape. An upper surface of the platen frame 62 is opened.
The platen body 61 is formed in an elongated shape elongated in the left and right direction. The platen body 61 constitutes an upper end of the platen 20. The platen body 61 is fixed to the platen frame 62 to close the opening on the upper surface of the platen frame 62. The platen body 61 has a plurality of suction holes for sucking the medium 2 placed on the platen 20. The suction hole penetrates the platen body 61 in the up and down direction. The upper surface of the platen body 61 serves as a medium placement surface 61a.
The platen body 61 is formed of aluminum or an aluminum alloy. The platen body 61 is formed by extrusion. At least the medium placement surface 61a of the surface of the platen body 61 is covered with a conductive coating. In this embodiment, the entire surface of the platen body 61 is covered with a conductive coating. The coating of this embodiment is a plating coating (plating layer). Specifically, the plating coating is a nickel plating coating (nickel plating layer), and is formed by electroless plating.
The hardness of the plating coating covering the surface of the platen body 61 is higher than the hardness of the portion of the platen body 61 excluding the plating coating. For example, the Vickers hardness of the plating coating is HV550, and the hardness of the portion of the platen body 61 excluding the plating coating is HV60. The medium placement surface 61a thus has high abrasion resistance. Both ends of the platen body 61 in the left and right direction are fixed to a metal frame (not illustrated). The platen body 61 is grounded via the frame or the like. That is, the medium placement surface 61a is grounded.

(Main effects of this embodiment)

As described above, in this embodiment, even if the medium contact angle increases as the tension bar 40 moves obliquely forward and downward, the biasing force of the tension coil spring 44 with respect to the tension bar 40 in the direction in which the tension of the medium 2 applied by the tension bar 40 decreases increases as the tension bar 40 moves obliquely forward and downward, and even if the medium contact angle decreases as the tension bar 40 moves obliquely backward and upward, the biasing force of the tension coil spring 44 with respect to the tension bar 40 in the direction in which the tension of the medium 2 applied by the tension bar 40 decreases decreases as the tension bar 40 moves obliquely backward and upward.
Thus, in this embodiment, the tension bar 40 can be moved in a forward and downward direction, and even when the tension bar 40 is brought into contact with the medium 2 after printing moving downward from an obliquely rear and upper side and the tension is applied to the medium 2 by the gravity acting on the tension bar 40, the fluctuation in the tension of the medium 2 applied by the tension bar 40 when the position of the tension bar 40 fluctuates can be suppressed.
In this embodiment, one tension coil spring 44 of the two tension coil springs 44 biases the right end of the tension bar 40, and the other tension coil spring 44 biases the left end of the tension bar 40. Therefore, in this embodiment, the tension bar 40 can be biased in a well-balanced manner using the two tension coil springs 44. Thus, in this embodiment, it is possible to effectively suppress the fluctuation in the tension of the medium 2 applied by the tension bar 40 when the position of the tension bar 40 fluctuates.
In this embodiment, the tension coil spring 44 engages with the slider 46 formed separately from the tension bar 40. Therefore, in this embodiment, when the medium 2 is set in the printer 1, even if the tension bar 40 is moved to a position where the tension bar 40 is supported by the tension bar support portion 56 (that is, even if the tension bar 40 is moved to a position deviated from the guide portion 43 on the upper side of the guide portion 43), it is not necessary to move the slider 46 to a position deviated from the guide groove 47a. Therefore, in this embodiment, when setting the medium 2 in the printer 1, it is not necessary to release the engagement state between the slider 46 and the tension coil spring 44 or to reengage the slider 46 and the tension coil spring 44. As a result, in this embodiment, the operation when setting the medium 2 in the printer 1 can be simplified.
In this embodiment, the linear scale 49 is fixed to the slider 46 that comes into contact with the tension bar 40 to bias the tension bar 40. Therefore, in this embodiment, it is not necessary to separately provide a member for fixing the linear scale 49. Therefore, in this embodiment, the configuration of the tension applying mechanism 12 can be simplified. In this embodiment, since the linear scale 49 is fixed to the slider 46 formed separately from the tension bar 40, even if the tension bar 40 is moved to a position where the tension bar 40 is supported by the tension bar support portion 56 when the medium 2 is set in the printer 1, it is not necessary to move the linear scale 49 to a position where a portion of the linear scale 49 is separated from between the light emitting unit and the light receiving unit of the sensors 50 and 51. Therefore, in this embodiment, the operation when setting the medium 2 in the printer 1 can be simplified.
In this embodiment, the ink mist generated at the time of discharging the ink from the head 17 is sucked by the suction mechanism 21 and adheres to the filter 26. Further, there is a risk that the ink mist will be solidified in the filter 26 and become a solid material, but in this embodiment, the filter 26 is disposed at a position shifted from the heater 10 in the horizontal direction. Therefore, in this embodiment, the solid material does not fall on the medium 2 passing above the heater 10. Therefore, in this embodiment, it is possible to prevent deterioration in print quality of the medium 2 due to the solid material solidified by the filter 26. In this embodiment, since the ink mist sucked from the plurality of intake ports 23 adheres to the common filter 26, one common filter 26 may be replaced when the filter 26 is replaced. Therefore, in this embodiment, replacement work of the filter 26 can be easily performed.
In this embodiment, the medium placement surface 61a is covered with a conductive plating coating. In this embodiment, the medium placement surface 61a is grounded. Therefore, in this embodiment, even if the conveying distance (feeding amount) of the long medium 2 conveyed along the medium placement surface 61a increases, it is possible to prevent electrification between the medium 2 and the medium placement surface 61a with which the medium 2 is in contact. Therefore, in this embodiment, even when printing is performed on the medium 2 while conveying the long medium 2, and even if the conveying distance of the medium 2 becomes long, the medium 2 can be accurately conveyed by the conveying roller 27.
On the other hand, for example, when the medium placement surface 61a is subjected to an alumite treatment in order to enhance the abrasion resistance of the medium placement surface 61a and the medium placement surface 61a is covered with an insulating alumite coating, the amount of electric charge between the medium placement surface 61a and the medium 2 increases as the conveying distance of the medium 2 increases. In this case, as the conveying distance of the medium 2 becomes longer, the electrical suction force of the medium 2 to the medium placement surface 61a due to static electricity becomes larger, and the medium 2 may not be accurately conveyed by the conveying roller 27.
Here, a result of an experiment conducted to examine how the electric suction force of the medium 2 to the medium placement surface 61a caused by static electricity fluctuates according to the conveying distance of the medium 2 will be described with reference to the table of Fig. 10. In this experiment, transfer paper was used as the medium 2. In this experiment, as an example, the medium 2 was conveyed for a predetermined distance on the medium placement surface 61a covered with the electroless nickel plating coating, then the medium 2 placed on the medium placement surface 61a was cut to a predetermined size, and then the tensile force when the medium 2 after cutting was pulled was measured. In this experiment, as a comparative example, a tensile force was measured when the medium 2 (that is, on the medium placement surface 61a covered with the insulating alumite coating) was conveyed for a predetermined distance on the alumite treated medium placement surface 61a, then the medium 2 placed on the medium placement surface 61a was cut to a predetermined size, and then the medium 2 after the cutting was pulled.
As illustrated in Fig. 10, in the comparative example, as the conveying distance of the medium 2 becomes longer, the electrical suction force of the medium 2 to the medium placement surface 61a due to static electricity becomes larger, and thus the tensile force of the medium 2 becomes larger. On the other hand, in the embodiment, even if the conveying distance of the medium 2 becomes long, the electric suction force of the medium 2 to the medium placement surface 61a due to static electricity hardly occurs, and thus the tensile force of the medium 2 hardly fluctuates.

(Other embodiments)

The above-described embodiment is an example of a preferred embodiment of the present invention, but is not limited thereto, and various modifications can be made without changing the gist of the present invention.
In the embodiment described above, the tension bar 40 and the slider 46 may be integrally formed. In the embodiment described above, one end of the tension coil spring 44 may be engaged with the tension bar 40. In this case, the slider 46 disposed on the left end side of the tension bar 40 becomes unnecessary. In this case, the tension applying mechanism 12 includes a biasing member that biases the slider 46 to which the linear scale 49 is fixed toward the obliquely rear and upper side in addition to the two tension coil springs 44.
In the embodiment described above, only the right end or the left end of the tension bar 40 may be biased by the tension coil spring 44. In the embodiment described above, the tension bar 40 may be biased to an obliquely rear and upper side by a spring member other than the tension coil spring 44. For example, the tension bar 40 may be biased to an obliquely rear and upper side by the compression coil spring. Further, the tension bar 40 may be biased to an obliquely rear and upper side by a biasing member other than the spring member. For example, the biasing member that biases the tension bar 40 to an obliquely rear and upper side may be a rubber biasing member. The biasing member that biases the tension bar 40 to an obliquely rear and upper side may be a cylinder such as an air cylinder or a damper such as a gas damper. The biasing member that biases the tension bar 40 to an obliquely rear and upper side may include a motor as a drive source.
In the embodiment described above, only the medium placement surface 61a of the platen body 61 may be covered with a conductive plating coating. Even in this case, the medium placement surface 61a is grounded. For example, the medium placement surface 61a is grounded via a conductive member in contact with the medium placement surface 61a. In the embodiment described above, the plating coating may be formed by electrolytic plating (electroplating). Furthermore, in the embodiment described above, the plating coating may be a plating coating other than the nickel plating coating. In the embodiment described above, at least the medium placement surface 61a of the surface of the platen body 61 may be covered with a conductive alumite coating. In the embodiment described above, for example, when the printer 1 performs printing only on the medium 2 on which electric charge is less likely to be accumulated between the medium placement surface 61a and the printer 1, the medium placement surface 61a may be covered with an insulating alumite coating. In this case, the Vickers hardness of the medium placement surface 61a is, for example, HV400 or more.
In the embodiment described above, as illustrated in Fig. 11, the number of guide rollers 9 arranged below the tension bar 40 and arranged between the heater 10 and the winding roll 7 in the front and rear direction may be one. In this case, the guide roller 9 is in contact with the upper surface of the medium 2. In the embodiment described above, one of the two guide rollers 9 disposed below the tension bar 40 and on the front side of the two guide rollers 9 disposed between the heater 10 and the winding roll 7 in the front and rear direction is in contact with the surface of the medium 2 on which the printing has been performed (printing surface). However, in the modified example illustrated in Fig. 11, the guide roller 9 is not in contact with the printing surface of the medium 2 between the heater 10 and the winding roll 7. In the embodiment described above, the two guide rollers 9 disposed below the tension bar 40 and disposed between the heater 10 and the winding roll 7 in the front and rear direction may be in contact with the upper surface of the medium 2. Even in this case, the guide roller 9 does not come into contact with the printing surface of the medium 2 between the heater 10 and the winding roll 7.

Hereinafter, a second embodiment of the present invention will be described with reference to the drawings.

(Overall configuration of Inkjet printer)

Fig. 12 is a side view for illustrating a configuration of an inkjet printer 101 according to the embodiment of the present invention. Fig. 13 is a schematic view for illustrating a configuration of a printing mechanism 103 illustrated in Fig. 12.
The inkjet printer 101 (hereinafter, referred to as a "printer 101") of this embodiment is, for example, a business inkjet printer, and performs printing on a long medium 102 (sheet-shaped medium 102) such as paper, fabric, or a resin sheet. In the printer 101, for example, printing is performed on the medium 102 having different widths. The printer 101 includes the printing mechanism 103 that performs printing on the medium 102, a medium conveying mechanism 104 that conveys the medium 102, a feeding roll holding unit 106 that holds a feeding roll 105 as the medium 102 before printing wound in a roll shape, and a winding roll holding unit 108 that holds a winding roll 107 as the medium 102 after printing wound in a roll shape.
When the Y direction in Fig. 12 and the like orthogonal to the up and down direction (vertical direction) is referred to as a "left and right direction", the width direction of the medium 102 orthogonal to the thickness direction of the medium 102 and the longitudinal direction of the medium 102 coincides with the left and right direction. That is, the left and right direction(Y direction) is the width direction of the medium 102. In the following description, an X direction in Fig. 12 and the like orthogonal to the up and down direction and the left and right direction is referred to as a "front and rear direction ". Further, the X1 direction side in Fig. 12 and the like, which is one side in the front and rear direction, is referred to as a "front" side, the X2 direction side in Fig. 12 and the like, which is the opposite side, is referred to as a "rear" side, the Y1 direction side in Fig. 13 and the like, which is one side in the left and right direction, is referred to as a "right" side, and the Y2 direction side in Fig. 13 and the like, which is the opposite side, is referred to as a "left" side. The left and right direction (that is, the width direction of the medium 102) of this embodiment is the main scanning direction.
The printing mechanism 103 includes an inkjet head 111 (hereinafter, referred to as a "head 111") that ejects ink onto the medium 102, a carriage 112 on which the head 111 is mounted, a carriage driving mechanism 113 that reciprocates the carriage 112 in a main scanning direction (left and right direction), and a support frame (Y bar) 114 that supports the carriage 112 to be movable in the left and right direction. The head 111 ejects ink downward. A plurality of nozzles for discharging ink is formed on a lower surface of the head 111. The head 111 includes a piezoelectric element for discharging ink from the nozzle. The carriage driving mechanism 113 includes, for example, a belt partially fixed to the carriage 112, a pulley around which the belt is stretched, and a motor for rotating the pulley.
Furthermore, the printing mechanism 103 includes a platen 115 on which the medium 102 when printing is placed, and a suction mechanism 116 for sucking and holding the medium 102 placed on the platen 115 on the platen 115. The platen 115 is disposed below the head 111 and the carriage 112. The thickness direction of the medium 102 when printing is performed by the head 111 coincides with the up and down direction. Specific configurations of the platen 115 and the suction mechanism 116 will be described later.
The printing mechanism 103 also includes a maintenance unit 118 for preventing clogging of the nozzles of the head 111. In the maintenance unit 118, the head 111 is cleaned so that clogging of a plurality of nozzles of the head 111 does not occur. Specifically, in the maintenance unit 118, flushing of driving the piezoelectric element to forcibly discharge the ink from the nozzle, ink suction of forcibly sucking the ink in the nozzle by covering the lower surface of the head 111 on which the nozzle is provided with the cap, and the like are performed.
As described above, in the printer 101, for example, printing is performed on the medium 102 having different widths. When the medium 102 having the widest width among the medium 102 on which printing is performed by the printer 101 is a maximum width medium 102A, and a range in which the maximum width medium 102A is disposed in the width direction (that is, in the left and right direction) of the medium 102 is a medium arrangement range MR (see Fig. 13), the maintenance unit 118 is disposed in a maintenance area MA that is an area deviated from the medium arrangement range MR in the left and right direction that is the main scanning direction. At this time, the maximum width medium 102A may be a medium having a maximum width that can be printed by the printer 101. In this embodiment, the maintenance unit 118 is disposed on the left side of the medium arrangement range MR. The left side (Y2 direction side) of this embodiment is a maintenance area side on which the maintenance area MA is disposed with respect to the medium arrangement range MR.
The medium conveying mechanism 104 conveys the long medium 102 in the longitudinal direction of the medium 102. The medium conveying mechanism 104 includes a conveying roller 119 and a pad roller 120 that is disposed to face the conveying roller 119 and is biased toward the conveying roller 119. The conveying roller 119 and the pad roller 120 are arranged behind the platen 115. The conveying roller 119 is connected to a driving mechanism that rotates the conveying roller 119. The driving mechanism includes a motor as a drive source. The medium 102 is conveyed while being sandwiched between the conveying roller 119 and the pad roller 120. The medium 102 before printing is conveyed from the rear side to the upper surface of the platen 115. The medium 102 after printing is conveyed forward from the upper surface of the platen 115 and then downward. That is, the medium 102 printed by the head 111 moves forward and then moves downward.
The feeding roll holding unit 106 is disposed below the printing mechanism 103. The feeding roll holding unit 106 includes a rotating shaft 123 inserted through the inner peripheral side of the feeding roll 105. The winding roll holding unit 108 is disposed below the printing mechanism 103. The winding roll holding unit 108 includes a rotating shaft 124 inserted through the inner peripheral side of the winding roll 107, and a driving mechanism that rotates the rotating shaft 124.

(Configurations of platen and suction mechanism)

Fig. 14 is a perspective view illustrating the suction mechanism 116 and the like illustrated in Fig. 12 from an obliquely rear lower side. Fig. 15(A) is a plan view of the platen 115 and the suction mechanism 116 illustrated in Fig. 12, and Fig. 15(B) is a front view of the platen 115 and the suction mechanism 116 illustrated in Fig. 12. Fig. 16 is a cross-sectional view for illustrating a configuration of the platen 115 and the suction mechanism 116 illustrated in Fig. 12.
The platen 115 is formed in an elongated shape elongated in the left and right direction. The platen 115 includes a platen body 127 which has the medium 102 placed on the upper surface and a platen frame 128 that supports the platen body 127 from below. The platen frame 128 is formed in a rectangular groove shape (square groove shape) elongated in the left and right direction. The platen frame 128 is formed by bending a metal thin plate such as a steel plate into a square groove shape. An upper surface of the platen frame 128 is opened. The platen body 127 is formed in an elongated shape elongated in the left and right direction. The platen body 127 constitutes an upper surface portion of the platen 115. The platen body 127 is fixed to the upper end of the platen frame 128 to close the opening on the upper surface of the platen frame 128.
Side plates 129 for supporting the platen frame 128 are arranged on both sides of the platen body 127 and the platen frame 128 in the left and right direction. A part of the side plate 129 constitutes a portion of the platen 115, and closes openings formed at both ends in the left and right direction of the platen body 127 and the platen frame 128. Inside the platen 115, a space defined by the platen body 127, the platen frame 128, and a part of the two side plates 129 is formed. That is, the platen 115 is formed in a hollow shape. A cover 130 disposed on the front side of the platen 115 and a cover 131 disposed on the rear side of the platen 115 are fixed to the side plate 129.
The platen body 127 has a plurality of suction holes 127a for sucking the medium 102 placed on the platen 115 (see Fig. 16). That is, a plurality of suction holes 127a are formed in the upper surface portion of the platen 115. A plurality of suction holes 127a are formed over substantially the entire area of the platen 115. The suction hole 127a penetrates the platen body 127 in the up and down direction. The plurality of suction holes 127a lead to an internal space of the platen 115 formed in a hollow shape.
A plurality of intake holes 28a arranged in the left and right direction are formed in the bottom surface portion of the platen frame 128 (see Fig. 16). That is, a plurality of intake holes 28a are formed in the lower surface portion of the platen 115. In this embodiment, four intake holes 28a arranged at equal intervals in the left and right direction are formed. The intake hole 28a penetrates the bottom surface portion of the platen frame 128 in the up and down direction. The four intake holes 28a communicate with an internal space of the platen 115 formed in a hollow shape.
The suction mechanism 116 includes an exhaust fan 134 for discharging the air in the internal space of the platen 115 to the outside of the printer 101, and a suction fan 135 for sucking the medium 102 placed on the platen 115. The suction mechanism 116 of this embodiment includes one exhaust fan 134 and four suction fans 135. In addition, the suction mechanism 116 includes a flow path forming portion 136 provided with an air flow path through which the air discharged from the internal space of the platen 115 passes. The suction fan 135 is a sirocco fan. The suction fan 135 is attached to a bottom surface (that is, the bottom surface of the platen 115) of the platen frame 128. Each of the four suction fans 135 is attached to a portion of the bottom surface of the platen frame 128 where the intake hole 28a is formed.
The flow path forming portion 136 includes a hollow flow path forming frame 137 which is formed in an elongated shape elongated in the left and right direction and in which an air flow path is formed. The flow path forming frame 137 is disposed below the suction fan 135. The flow path forming portion 136 includes a tubular connection member 138 that connects the suction fan 135 and the flow path forming frame 137. Specifically, the flow path forming portion 136 includes four connection members 138 connecting each of the four suction fans 135 and the flow path forming frame 137. In this embodiment, one flow path forming frame 137 and four connection members 138 constitute the flow path forming portion 136. An inner peripheral side of the connection member 138 formed in a tubular shape serves as an air flow path. The intake hole 28a communicates with an air flow path formed in the flow path forming portion 136. Specifically, the intake hole 28a communicates with an air flow path formed in the flow path forming portion 136 via the suction fan 135.
The flow path forming frame 137 is formed in a flat substantially rectangular parallelepiped box shape having a small thickness in the up and down direction. The flow path forming frame 137 includes a thin plate-shaped upper surface portion constituting the upper surface of the flow path forming frame 137, a thin plate-shaped lower surface portion constituting the lower surface of the flow path forming frame 137, a thin plate-shaped side surface portion constituting the side surface in the front and rear direction of the flow path forming frame 137, and a thin plate-shaped side surface portion constituting the side surface in the left and right direction of the flow path forming frame 137, and is formed in a hollow shape as described above.
The length of the flow path forming frame 137 in the left and right direction is longer than the length of the platen 115 in the left and right direction. The right end of the flow path forming frame 137 is disposed on the right side of the right end of the platen 115, and the left end of the flow path forming frame 137 is disposed on the left side of the left end of the platen 115. Two side plates 129 are fixed to the upper surface of the flow path forming frame 137. The flow path forming frame 137 also functions to support the platen 115 via the side plate 129.
The connection member 138 is formed in a cylindrical shape by a thin film. The connection member 138 of this embodiment is formed in a square tubular shape. The upper end of the connection member 138 is connected to the suction fan 135. The lower end of the connection member 138 is connected to the upper surface portion of the flow path forming frame 137. Specifically, an opening (through hole) penetrating in the up and down direction is formed in the upper surface portion of the flow path forming frame 137, and the lower end of the connection member 138 is connected to a portion where the opening is formed in the upper surface portion of the flow path forming frame 137. The inner peripheral side of the connection member 138 communicates with the internal space of the flow path forming frame 137. The connection member 138 is installed in an inclined state toward the left side as it goes downward when viewed from the front side (see Fig. 15(B)).
An exhaust hole 137a through which air is discharged from the inside of the flow path forming frame 137 toward the outside of the printer 101 by the exhaust fan 134 is formed in a lower surface portion of the flow path forming frame 137 (see Fig. 14). That is, the flow path forming portion 136 is provided with the exhaust hole 137a through which air is discharged toward the outside of the printer 101 by the exhaust fan 134. The exhaust hole 137a is formed at the left end of the flow path forming frame 137. The exhaust hole 137a penetrates the lower surface portion of the flow path forming frame 137 in the up and down direction and communicates with the internal space of the flow path forming frame 137. The exhaust hole 137a is formed in only one place. The air discharged from the exhaust fan 134 passes through the exhaust hole 137a.
The exhaust fan 134 is an axial fan. The exhaust fan 134 is disposed such that the axial direction of the exhaust fan 134 coincides with the up and down direction. The exhaust fan 134 is attached to the left end of the flow path forming frame 137. That is, the exhaust fan 134 is attached to the flow path forming portion 136. The exhaust fan 134 is attached to the lower surface portion of the flow path forming frame 137. Specifically, the exhaust fan 134 is attached to the upper surface of the lower surface portion of the flow path forming frame 137 to close the exhaust hole 137a. The exhaust fan 134 is disposed inside the flow path forming frame 137. The exhaust fan 134 is disposed at the same position as the exhaust hole 137a in the front and rear direction and the left and right direction, and the exhaust fan 134 and the exhaust hole 137a overlap when viewed from the up and down direction. The exhaust fan 134 discharges air downward.
A filter 140 is attached to an upper surface side of the exhaust fan 134. The air discharged from the internal space of the platen 115 passes through the filter 140 before being discharged to the outside of the printer 101 by the exhaust fan 134. That is, the suction mechanism 116 includes the filter 140 through which the air discharged from the internal space of the platen 115 through the four intake holes 28a passes. The filter 140 is disposed at the same position as the exhaust fan 134 in the front and rear direction and the left and right direction. That is, the filter 140 is disposed at the same position as the exhaust hole 137a in the front and rear direction and the left and right direction.
The exhaust hole 137a is disposed at a position deviated from the medium arrangement range MR in the left and right direction. Specifically, as described above, the exhaust hole 137a is formed at the left end of the flow path forming frame 137, and is disposed on the left side of the medium arrangement range MR. The exhaust hole 137a is disposed on the left side of the platen 115 and is disposed in the maintenance area MA. The exhaust fan 134 and the filter 140 arranged at the same position as the exhaust hole 137a in the left and right direction are also arranged at positions deviated from the medium arrangement range MR in the left and right direction. That is, the exhaust fan 134 and the filter 140 are also arranged on the left side of the medium arrangement range MR. The exhaust fan 134 and the filter 140 are also disposed on the left side of the platen 115 and in the maintenance area MA.
In the printer 101, when the suction fan 135 operates, the air in the internal space of the platen 115 is discharged. When the air in the internal space of the platen 115 is discharged, the medium 102 is sucked onto the upper surface of the platen 115, and the medium 102 is held by the platen 115. When the exhaust fan 134 operates, the air in the inner peripheral side of the connection member 138 and the internal space of the flow path forming frame 137 is sucked and discharged from the exhaust hole 137a to the outside of the printer 101. That is, when the exhaust fan 134 operates, the air in the flow path of the flow path forming portion 136 is sucked and discharged from the exhaust hole 137a to the outside of the printer 101. The exhaust fan 134 and the suction fan 135 operate when printing of the medium 102 is performed.

(Main effects of this embodiment)

As described above, in this embodiment, the flow path forming portion 136 in which the flow path of the air discharged from the internal space of the platen 115 is formed is provided with the exhaust hole 137a through which the air is discharged toward the outside of the printer 101 by the exhaust fan 134. In this embodiment, the exhaust hole 137a is disposed at a position deviated from the medium arrangement range MR in the left and right direction. Therefore, in this embodiment, when the air that has entered the platen 115 to suck the medium 102 into the platen 115 is discharged toward the outside of the printer 101, even if the solid material solidified by the ink mist is discharged from the exhaust hole 137a together with the air, the solid material can be prevented from adhering to the medium 102.
Therefore, in this embodiment, even if the solid material in which the ink mist is solidified is discharged toward the outside of the printer 101 together with the air entering the inside of the hollow platen 115 when sucking the medium 102 into the platen 115, it is possible to prevent the medium 102 from being contaminated due to the solid material. In particular, in this embodiment, since the exhaust hole 137a is formed at the left end of the flow path forming frame 137 formed in an elongated shape elongated in the left and right direction, the exhaust hole 137a can be moved away from the medium 102 in the left and right direction. Therefore, in this embodiment, even if the solid material in which the ink mist is solidified is discharged from the exhaust hole 137a together with the air, it is possible to effectively prevent the medium 102 from being contaminated due to the solid material.
In this embodiment, the exhaust fan 134 is disposed at the same position as the exhaust hole 137a in the front and rear direction and the left and right direction. Therefore, in this embodiment, the air can be efficiently discharged from the exhaust hole 137a toward the outside of the printer 101 by the exhaust fan 134. Furthermore, in this embodiment, since the suction mechanism 116 includes the suction fan 135 in addition to the exhaust fan 134, the medium 102 placed on the platen 115 can be reliably sucked to the platen 115 by the suction fan 135.
In this embodiment, the connection member 138 is formed in a tubular shape by a thin film. Therefore, in this embodiment, the opening of the flow path forming frame 137 and the suction fan 135 connected to the upper end of the connection member 138 can be easily connected by the flexible connection member 138 even if the relative positional accuracy is not high between the portion of the upper surface portion of the flow path forming frame 137 connected to the lower end of the connection member 138 where the opening is formed and the suction fan 135.
In this embodiment, the air discharged from the internal space of the platen 115 through four vent holes 128a passes through one filter 140 and is discharged to the outside of the printer 101. Therefore, in this embodiment, when the filter 140 is replaced, one common filter 140 may be replaced. Therefore, in this embodiment, replacement work of the filter 140 can be easily performed.

(Modified example of inkjet printer)

Fig. 17 is a side view for illustrating a configuration of the printer 101 according to another embodiment of the present invention. Fig. 18 is a schematic view for illustrating a configuration of the suction mechanism 116 included in the printing mechanism 103 illustrated in Fig. 17. Furthermore, in Figs. 17 and 18, the same reference numerals are given to the same configurations as those in the above-described embodiment.
In the embodiment described above, as illustrated in Fig. 17, the printer 101 may include a heater 145 for heating the medium 102 after printing, a tension applying mechanism 146 for applying tension to the medium 102 before printing, a tension applying mechanism 147 for applying tension to the medium 102 after printing, and a plurality of guide rollers 148 for guiding the medium 102 to be conveyed. Hereinafter, a modified example of the printer 101 illustrated in Figs. 17 and 18 will be described.
In this modified example, the medium conveying mechanism 104 does not include the pad roller 120. The conveying roller 119 is a rubber roller whose surface is formed of rubber. The feeding roll holding unit 106 is disposed below the platen 115. The feeding roll holding unit 106 is disposed behind the printing mechanism 103. The winding roll holding unit 108 is disposed, for example, below the feeding roll holding unit 106, and is disposed behind the printing mechanism 103.
The tension applying mechanism 146 includes a tension bar 150 that comes into contact with the medium 102 before printing between the head 111 and the feeding roll holding unit 106 in the moving path of the medium 102 to apply tension to the medium 102, and a guide portion that linearly guides the tension bar 150 in the up and down direction. The tension bar 150 comes into contact with the medium 102 moving forward from the feeding roll holding unit 106 toward the printing mechanism 103 from above. The tension bar 150 applies tension to the medium 102 by gravity acting on the tension bar 150. At the time of printing on the medium 102, the tension bar 150 linearly moves in the up and down direction in accordance with the movement of the medium 102.
The tension applying mechanism 147 includes a tension bar 151 that comes into contact with the medium 102 after printing between the head 111 and the winding roll holding unit 108 in the moving path of the medium 102 to apply tension to the medium 102. The tension bar 151 is disposed in front of and below the platen 115. The tension bar 151 is linearly movable in a forward and downward direction as indicated by an arrow in Fig. 12. The tension applying mechanism 147 further includes a guide portion that linearly guides the tension bar 151 in a forward and downward direction, and a tension coil spring that biases the tension bar 151 to an obliquely rear and upper side.
The tension bar 151 comes into contact with the medium 102 after printing moving from the platen 115 forward and then moving downward from the obliquely rear and upper side. The tension bar 151 applies tension to the medium 102 by gravity acting on the tension bar 151. At the time of printing on the medium 102, the tension bar 151 linearly moves in a forward and downward direction in accordance with the movement of the medium 102. An inclination θ (see Fig. 17) of the moving direction of the tension bar 151 with respect to the front and rear direction when viewed from the left and right direction is 30° to 60°.
The heater 145 is disposed below the platen 115. That is, the platen 115 is disposed above the heater 145. The heater 145 is disposed below the tension bar 150. The heater 145 is disposed below and behind the tension bar 151. The heater 145 is disposed below and in front of the feeding roll 105 and the winding roll 107. That is, the feeding roll 105 and the winding roll 107 are arranged above and behind the heater 145. As described above, the medium 102 printed by the printing mechanism 103 moves forward and then moves downward. The medium 102 moved downward passes through the tension bar 151 and then moves backward. The medium 102 moving backward passes above the heater 145.
The plurality of guide rollers 148 are driven rollers that rotate with the movement of the medium 102. The two guide rollers 148 of the plurality of guide rollers 148 are arranged on both sides of the tension bar 150 in the front and rear direction and are arranged above the tension bar 150. One guide roller 148 of the plurality of guide rollers 148 is disposed on the front side of the platen 115, and functions to change the moving direction of the medium 102 moving from the platen 115 forward to a downward direction. One guide roller 148 of the plurality of guide rollers 148 is disposed below the tension bar 151 and on the front side of the printer 101, and functions to change the moving direction of the medium 102 moving downward to a backward direction.
In this modified example, the suction mechanism 116 does not include the suction fan 135. The upper end of the connection member 138 is connected to, for example, a portion of the bottom surface of the platen frame 128 where the intake hole 28a is formed. That is, in this modified example, one end of the air flow path 136a formed in the flow path forming portion 136 is connected to the four intake holes 28a, and the other end of the flow path 136a is connected to the exhaust fan 134 via the filter 140. That is, the exhaust fan 134 is connected to the four intake holes 28a via the flow path 136a.
The exhaust fan 134 also sucks the medium 102 placed on the platen 115. When the exhaust fan 134 operates, the air in the internal space of the platen 115 is discharged from all of the four intake holes 28a, and the air in the flow path 136a is sucked and discharged from the exhaust hole 137a to the outside of the printer 101. The exhaust fan 134 operates when printing of the medium 102 is performed. Similarly to the embodiment described above, the exhaust hole 137a, the exhaust fan 134, and the filter 140 are arranged at positions deviated from the medium arrangement range MR in the left and right direction. The exhaust hole 137a, the exhaust fan 134, and the filter 140 are arranged at positions shifted from the heater 145 in the left and right direction. Specifically, the exhaust hole 137a, the exhaust fan 134, and the filter 140 are arranged on the left side of the heater 145.
In this modified example, the exhaust fan 134 also has a function of sucking the medium 102 placed on the platen 115. Therefore, the configuration of the suction mechanism 116 can be simplified as compared with the case where the suction fan 135 is provided. Furthermore, in this modified example, since the filter 140 is disposed at a position deviated from the medium arrangement range MR in the left and right direction and is disposed at a position shifted from the heater 145 in the left and right direction, the ink mist attached to the filter 140 is solidified to become a solid material, and even if the solid material falls, the solid material can be prevented from being attached to the medium 102 passing above the heater 145.

(Other embodiments)

The above-described embodiment is an example of a preferred embodiment of the present invention, but is not limited thereto, and various modifications can be made without changing the gist of the present invention.
In the embodiment described above, the exhaust hole 137a may be disposed at a position deviated from the maintenance area MA. In the embodiment described above, the exhaust hole 137a may be formed at the right end of the flow path forming frame 137. Even in this case, the exhaust hole 137a is disposed on the right side of the medium arrangement range MR, and is disposed at a position deviated from the medium arrangement range MR in the left and right direction. In the embodiment described above, the plurality of exhaust holes 137a may be formed in the flow path forming frame 137. Even in this case, all of the plurality of exhaust holes 137a are arranged at positions deviated from the medium arrangement range MR in the left and right direction.
In the embodiment described above, the exhaust fan 134 may be disposed at a position different from the exhaust hole 137a in at least one of the front and rear direction and the left and right direction. In this case, the exhaust fan 134 and the filter 140 may be arranged in the medium arrangement range MR in the left and right direction. In the embodiment described above, the connection member 138 may be formed of, for example, a hard resin material. Furthermore, in the embodiment described above, the flow path forming portion 136 may be configured by one member. In the embodiment described above, the filter 140 may not be attached to the exhaust fan 134. In the embodiment described above, the exhaust fan 134 may be a fan other than the axial fan, and the suction fan 135 may be a fan other than the sirocco fan.

Hereinafter, a third embodiment of the present invention will be described with reference to the drawings.

(Schematic configuration of inkjet printer)

Fig. 19 is a schematic view for illustrating a configuration of an inkjet printer 201 according to the embodiment of the present invention. Fig. 20 is a bottom view of a head unit 204 illustrated in Fig. 19.
The inkjet printer 201 (hereinafter, referred to as a "printer 201") of this embodiment is, for example, a business inkjet printer, and ejects ink to perform printing on a medium 202 such as paper. The printer 201 includes the head unit 204 having a plurality of inkjet heads 203 (hereinafter, referred to as a "head 203") that eject ink toward the medium 202, a carriage 205 on which the head unit 204 is mounted, a carriage driving mechanism 206 that moves the carriage 205 in the main scanning direction, and a guide rail 207 for guiding the carriage 205 in the main scanning direction. In the following description, a main scanning direction (Y direction in Fig. 19 and the like) is referred to as a "left and right direction ", and a sub-scanning direction (X direction in Fig. 19 and the like) orthogonal to the up and down direction and the main scanning direction is referred to as a" front and rear direction ".
The head 203 ejects ink downward. A platen 208 is disposed below the head 203. The medium 202 when printing is placed on the platen 208. The medium 202 placed on the platen 208 is conveyed in the front and rear direction by a medium feeding mechanism (not illustrated). The carriage driving mechanism 206 includes, for example, two pulleys, a belt stretched between the two pulleys and partially fixed to the carriage 205, and a motor that rotates the pulleys. When performing printing on the medium 202, the head 203 discharges the ink toward the upper surface of the medium 202 placed on the platen 208 while the carriage 205 is guided by the guide rail 207 to reciprocate in the left and right direction.
The head unit 204 includes a plurality of heads 203 and a head fixing member to which the plurality of heads 203 are fixed. As illustrated in Fig. 20, in the head unit 204, for example, the plurality of heads 203 arranged in the left and right direction at constant intervals is disposed at two positions in the front and rear direction. The outer shape of the head unit 204 when viewed from the up and down direction is a rectangular shape with the left and right direction as a long side direction.
A plurality of nozzles for discharging ink are formed on a lower surface of the head 203. On the lower surface of the head 203, a nozzle row 203a is configured by a plurality of nozzles arranged in the front and rear direction. For example, four nozzle rows 203a are formed in one head 203. The head 203 includes a plurality of piezoelectric elements for discharging ink from each of the plurality of nozzles. The lower surface of the head unit 204 is a nozzle surface 204a on which a plurality of nozzles are formed. As described above, since the outer shape of the head unit 204 when viewed from the up and down direction is a rectangular shape in which the left and right direction is the long side direction, the outer shape of the nozzle surface 204a is a rectangular shape in which the left and right direction is the long side direction.
The printer 201 further includes a maintenance unit 209 for performing maintenance of the head 203. When an area where printing is performed on the medium 202 by the head 203 in the left and right direction (main scanning direction) is a printing area PA, the maintenance unit 209 is installed in the maintenance area MA that is an area deviated from the printing area PA in the left and right direction. In the maintenance unit 209, the head 203 is cleaned so that the nozzles of the head 203 are not clogged. Specifically, the maintenance unit 209 performs purging for forcibly ejecting ink from the nozzles of the head 203, wiping for wiping the nozzle surface 204a with a wiper(not illustrated), and the like.
When the maintenance unit 209 cleans the head 203, the head unit 204 moves to the maintenance area MA. The maintenance unit 209 includes a moisturizing device 210 (see Fig. 21) that moisturizes the nozzle surface 204a of the head unit 204 at the time of non-printing in which the medium 202 is not being printed (that is, at the time of non-printing in which the head 203 does not eject ink). Hereinafter, the configuration of the moisturizing device 210 will be described.

(Configuration of moisturizing device)

Fig. 21 is a schematic view for illustrating a configuration of the moisturizing device 210 according to the embodiment of the present invention. Fig. 22 is a block diagram for illustrating a configuration of the moisturizing device 210 illustrated in Fig. 21. Fig. 23(A) is a plan view for illustrating a configuration of a main container 213 illustrated in Fig. 21, and Fig. 23(B) is a cross-sectional view taken along line E-E of Fig. 23(A).
The moisturizing device 210 includes the main container 213 in which the moisturizing liquid M for moisturization is stored, and a plurality of water absorbing members 214 disposed in the main container 213. The moisturizing liquid M is, for example, ion-replaced water. In addition, the moisturizing device 210 includes a sub-tank 215 as a sub-container that stores the moisturizing liquid M and is connected to the main container 213, a moisturizing liquid supply unit 216 that supplies the moisturizing liquid M to the main container 213, a moisturizing liquid discharge unit 217 that discharges the moisturizing liquid M from the main container 213, and a liquid level detection mechanism 218 that detects a height of a liquid level of the moisturizing liquid M in the sub-tank 215. Furthermore, the moisturizing device 210 includes a controller 220 for controlling the moisturizing device 210. The controller 220 constitutes a part of a printer controller for controlling the printer 201. In Fig. 21, illustration of the water absorbing member 214 is omitted.
The main container 213 is a moisturizing bucket for moisturizing the nozzle surface 204a. The main container 213 is formed in a box shape whose upper surface is opened. The main container 213 is formed in a flat rectangular parallelepiped box shape having a low height in the up and down direction. The outer shape of the main container 213 when viewed from the up and down direction is a rectangular shape in which the left and right direction is a long side direction. The outer shape of the main container 213 is larger than the outer shape of the head unit 204. As described above, the maintenance unit 209 is disposed in the maintenance area MA, and the main container 213 is disposed at a position deviated from the printing area PA in the left and right direction.
The water absorbing member 214 is immersed in the moisturizing liquid M in the main container 213, and absorbs and holds the moisturizing liquid M in the main container 213. Water absorbing member 214 is formed of sponge, for example. The water absorbing member 214 is formed in a rectangular parallelepiped shape elongated in the front and rear direction. As illustrated in Fig. 23(B), the water absorbing member 214 is attached to a holding member 222 fixed to the bottom surface of the main container 213. The holding member 222 includes a flat plate-shaped insertion portion 222a whose thickness direction is the up and down direction. A slit into which the insertion portion 222a is inserted is formed in the water absorbing member 214. By inserting the insertion portion 222a into the slit of the water absorbing member 214, the water absorbing member 214 is fixed to the holding member 222.
The plurality of water absorbing members 214 are arranged in the left and right direction at constant intervals. The arrangement pitch of the plurality of water absorbing members 214 in the left and right direction is equal to the arrangement pitch of the plurality of heads 203 in the left and right direction. The upper surface of the water absorbing member 214 is a rectangular flat surface orthogonal to the up and down direction. The upper surface of the water absorbing member 214 is disposed above the liquid level of the moisturizing liquid M in the main container 213. The upper surface of the water absorbing member 214 is disposed below the upper end of the main container 213.
At the time of non-printing time in which the medium 202 is not being printed, the liquid level of the moisturizing liquid M in the main container 213 is disposed below the nozzle surface 204a (see Fig. 23(B)). When the nozzle surface 204a is moisturized, the upper surface of the water absorbing member 214 is disposed below the head 203. The lower surface of the head 203 on which the nozzle row 203a is formed and the upper surface of the water absorbing member 214 face each other with a predetermined gap therebetween. An air layer having high humidity is formed between the lower surface of head 203 and the upper surface of the water absorbing member 214. The carriage 205 includes a lifting mechanism 245 (see Fig. 19) for lifting and lowering the head unit 204 with respect to the main container 213.
An overflow pipe 223 for discharging the moisturizing liquid M from the main container 213 when the height of the liquid level of the moisturizing liquid M in the main container 213 exceeds a predetermined height is attached to the main container 213. The overflow pipe 223 is disposed in the main container 213. The overflow pipe 223 is formed in a straight tubular shape whose longitudinal direction is the up and down direction. The overflow pipe 223 is connected to a waste liquid tank 232 described later constituting a part of the moisturizing liquid discharge unit 217 via a predetermined pipe 224 and a pipe 233 described later constituting a part of the moisturizing liquid discharge unit 217.
The upper end of the overflow pipe 223 is disposed below the upper surface of the water absorbing member 214, for example. The lower end of the overflow pipe 223 is connected to the upper end of the pipe 224 on the bottom surface of the main container 213, for example. The waste liquid tank 232 is disposed below the main container 213. The moisturizing liquid M discharged through the overflow pipe 223 is discharged from the main container 213 due to the water head difference. In Fig. 23, illustration of the overflow pipe 223 is omitted.
The sub-tank 215 is formed in a rectangular parallelepiped box shape. The upper surface of the sub-tank 215 is covered with a lid. An opening penetrating in the up and down direction is formed in the lid, and the inside of the sub-tank 215 and the outside of the sub-tank 215 communicate with each other through the opening. The sub-tank 215 is disposed in the vicinity of the main container 213. The sub-tank 215 is connected to the main container 213 via a pipe 25. The inside of the sub-tank 215 and the inside of the main container 213 communicate with each other via the pipe 25, and the moisturizing liquid M is able to flow between the main container 213 and the sub-tank 215. The height of the liquid level of the moisturizing liquid M in the sub-tank 215 is equal to the height of the liquid level of the moisturizing liquid M in the main container 213. That is, the sub-tank 215 is installed at a position where the height of the liquid level of the moisturizing liquid M in the sub-tank 215 is equal to the height of the liquid level of the moisturizing liquid M in the main container 213.
The moisturizing liquid supply unit 216 includes a liquid supply tank 228 that stores the moisturizing liquid M supplied to the main container 213, a pipe 229 that connects the liquid supply tank 228 and the main container 213, a pump 230 that sends the moisturizing liquid M in the liquid supply tank 228 to the main container 213, and an electromagnetic valve 231 that is disposed in the middle of the pipe 229. The pump 230 is disposed in the middle of the pipe 229. The pump 230 and the electromagnetic valve 231 are electrically connected to the controller 220. When the pump 230 is driven in a state where the electromagnetic valve 231 is turned on, the moisturizing liquid M is supplied from the liquid supply tank 228 to the main container 213.
The moisturizing liquid discharge unit 217 includes a waste liquid tank 232 that stores the moisturizing liquid M discharged from the main container 213, a pipe 233 having one end connected to the pipe 25 and the other end connected to the waste liquid tank 232, and an electromagnetic valve 234 disposed in the middle of the pipe 233. The electromagnetic valve 234 is electrically connected to the controller 220. As described above, the waste liquid tank 232 is disposed below the main container 213. When the electromagnetic valve 234 is turned on, the moisturizing liquid M is discharged from the main container 213 to the waste liquid tank 232 due to the water head difference.
The liquid level detection mechanism 218 detects the amount of the moisturizing liquid M in the sub-tank 215 by detecting the height of the liquid level of the moisturizing liquid M in the sub-tank 215. As described above, since the sub-tank 215 is installed at a position where the height of the liquid level of the moisturizing liquid M in the sub-tank 215 is equal to the height of the liquid level of the moisturizing liquid M in the main container 213, the liquid level detection mechanism 218 indirectly detects the height of the liquid level of the moisturizing liquid M in the main container 213. The liquid level detection mechanism 218 indirectly detects the amount of the moisturizing liquid M in the main container 213.
The liquid level detection mechanism 218 includes a float 237 which floats on the moisturizing liquid M in the sub-tank 215, a permanent magnet 238 which is a detected portion attached to the float 237, and sensors 239 to 241 which are arranged outside the sub-tank 215 and detect the permanent magnet 238. The liquid level detection mechanism 218 of this embodiment includes three sensors 239 to 241. The permanent magnet 238 is incorporated in the float 237. The sensors 239 to 241 are magnetic sensors such as Hall ICs. The sensors 239 to 241 are fixed to, for example, the outer surface of the sub-tank 215. The sensors 239 to 241 are electrically connected to the controller 220.
The sensor 239 is fixed to the outer surface of the sub-tank 215 on the upper end side of the sub-tank 215. The sensor 240 is fixed to the outer surface of the sub-tank 215 below the sensor 239. The sensor 241 is fixed to the outer surface of the sub-tank 215 on the lower end side of the sub-tank 215. The sensor 239 is a sensor for detecting that the height of the liquid level of the moisturizing liquid M in the sub-tank 215 is higher than a predetermined upper limit position. The sensor 240 is a sensor for detecting that the height of the liquid level of the moisturizing liquid M in the sub-tank 215 is within an appropriate range. The sensor 241 is a sensor for detecting that the height of the liquid level of the moisturizing liquid M in the sub-tank 215 is lower than a predetermined lower limit position. In this embodiment, a part of the detection range of the permanent magnet 238 by the sensor 239 and a part of the detection range of the permanent magnet 238 by the sensor 240 overlap.
When the height of the liquid level of the moisturizing liquid M in the sub-tank 215 becomes higher than a predetermined upper limit position, the permanent magnet 238 incorporated in the float 237 is detected by the sensor 239. At this time, the permanent magnet 238 may also be detected by the sensor 240. When the height of the liquid level of the moisturizing liquid M in the sub-tank 215 is within an appropriate range, the permanent magnet 238 is detected by the sensor 240 but not detected by the sensor 239. When the height of the liquid level of the moisturizing liquid M in the sub-tank 215 becomes lower than a predetermined lower limit position, the permanent magnet 238 is detected by the sensor 241. When the height of the liquid level of the moisturizing liquid M in the sub-tank 215 is within an appropriate range, the height of the liquid level of the moisturizing liquid M in the main container 213 is within an appropriate range, and the nozzle surface 204a can be appropriately moisturized using the moisturizing liquid M in the main container 213.
For example, when the float 237 is disposed at the upper limit position of the detection range of the permanent magnet 238 by the sensor 240, the height of the liquid level of the moisturizing liquid M in the main container 213 is higher than the upper end of the overflow tube 223. The height of the liquid level of the moisturizing liquid M in the main container 213 when the float 237 is disposed at the lower limit position of the detection range of the permanent magnet 238 by the sensor 240 is lower than the height of the upper end of the overflow tube 223. In this embodiment, when the permanent magnet 238 is not detected by the sensor 240 and the permanent magnet 238 is detected by the sensor 239, clogging or the like occurs in the overflow tube 223, and the moisturizing liquid M cannot be discharged through the overflow tube 223.
The moisturizing liquid supply unit 216 supplies the moisturizing liquid M to the main container 213 based on the detection result of the liquid level detection mechanism 218, and the moisturizing liquid discharge unit 217 discharges the moisturizing liquid M from the main container 213 based on the detection result of the liquid level detection mechanism 218. That is, in the moisturizing device 210, the supply of the moisturizing liquid M to the main container 213 and the discharge of the moisturizing liquid M from the main container 213 are automatically performed based on the detection result of the liquid level detection mechanism 218.
Specifically, when the float 237 is disposed between the lower limit position of the detection range of the permanent magnet 238 by the sensor 240 and the upper limit position of the detection range of the permanent magnet 238 by the sensor 241, and the permanent magnet 238 is not detected in any of the sensors 239 to 241, the controller 220 turns on the electromagnetic valve 231 and drives the pump 230 to supply the moisturizing liquid M from the liquid supply tank 228 to the main container 213 until the permanent magnet 238 is detected by the sensor 240. When the permanent magnet 238 is detected by the sensor 239, the controller 220 turns on the electromagnetic valve 234, and discharges the moisturizing liquid M from the main container 213 to the waste liquid tank 232 until the permanent magnet 238 is detected by the sensor 240 and the permanent magnet 238 is no longer detected by the sensor 239.
In this embodiment, when the permanent magnet 238 is detected by the sensor 241, if the moisturizing liquid supply unit 216 automatically supplies the moisturizing liquid M to the main container 213, it takes time to supply the moisturizing liquid M. Therefore, when the permanent magnet 238 is detected by the sensor 241, the moisturizing liquid M is manually supplied to the main container 213, and the moisturizing liquid M is supplied to the main container 213 in a short time until the permanent magnet 238 is detected by the sensor 240.

(Main effects of this embodiment)

As described above, in this embodiment, the liquid level detection mechanism 218 indirectly detects the height of the liquid level of the moisturizing liquid M in the main container 213. In this embodiment, the moisturizing liquid supply unit 216 supplies the moisturizing liquid M to the main container 213 based on the detection result of the liquid level detection mechanism 218. That is, in this embodiment, the moisturizing liquid supply unit 216 supplies the moisturizing liquid M to the main container 213 based on the indirect detection result of the height of the liquid level of the moisturizing liquid M in the main container 213. Specifically, in this embodiment, the moisturizing liquid supply unit 216 automatically supplies the moisturizing liquid M to the main container 213 so that the height of the liquid level of the moisturizing liquid M in the sub-tank 215 falls within an appropriate range (that is, the height of the liquid level of the moisturizing liquid M in the main container 213 falls within an appropriate range), and the nozzle surface 204a can be appropriately moisturized using the moisturizing liquid M in the main container 213.
Therefore, in this embodiment, it is possible to prevent an excessive decrease in the liquid level of the moisturizing liquid M stored in the main container 213 so that the nozzle surface 204a can be appropriately moisturized using the moisturizing liquid M in the main container 213. Furthermore, in this embodiment, since the moisturizing liquid discharge unit 217 discharges the moisturizing liquid M from the main container 213 based on the detection result of the liquid level detection mechanism 218 (that is, the moisturizing liquid M is discharged from the main container 213 based on the indirect detection result of the height of the liquid level of the moisturizing liquid M in the main container 213), even in a situation where the moisturizing liquid M cannot be discharged via the overflow pipe 223, it is possible to prevent the moisturizing liquid M from overflowing from the box-shaped main container 213 whose upper surface is opened.
In this embodiment, the liquid level detection mechanism 218 detects the height of the liquid level of the moisturizing liquid M in the sub-tank 215, and the float 237 floats in the moisturizing liquid M not in the main container 213 but in the sub-tank 215. Therefore, in this embodiment, the float 237 and the nozzle surface 204a do not interfere with each other. Therefore, in this embodiment, the moisturizing of the nozzle surface 204a is not hindered by the influence of the float 237. In this embodiment, since the float 237 and the nozzle surface 204a do not interfere with each other, the main container 213 can be disposed without considering the position of the float 237. Therefore, in this embodiment, the degree of freedom in arrangement of the main container 213 can be increased. In this embodiment, the nozzle surface 204a and the like are not damaged due to interference between the float 237 and the nozzle surface 204a.

(Modified example 1 of moisturizing device)

Fig. 24(A) is a plan view for illustrating a configuration of the main container 213 and the like according to another embodiment of the present invention, Fig. 24(B) is a cross-sectional view taken along line F-F of Fig. 24(A), Fig. 24(C) is a cross-sectional view taken along line G-G of Fig. 24(A), and Fig. 24(D) is a cross-sectional view taken along line H-H of Fig. 24(A). In Fig. 24, the same components as those in the above-described embodiment are denoted by the same reference numerals. In Fig. 24(B), illustration of the water absorbing member 214 and the holding member 222 is omitted.
In the embodiment described above, the moisturizing device 210 may include a seal member 250 that can be brought into contact with the outer peripheral end of the nozzle surface 204a of the head unit 204 from below. In this case, the outer shape of the nozzle surface 204a formed in a rectangular shape with the left and right direction as the long side direction is larger than the outer shape of the main container 213 formed in a rectangular shape with the left and right direction as the long side direction. Specifically, the width of the nozzle surface 204a in the left and right direction is larger than the width of the main container 213 in the left and right direction, and the width of the nozzle surface 204a in the front and rear direction is larger than the width of the main container 213 in the front and rear direction. In the following description, one side in the left and right direction (the right side in Fig. 24(A)), which is the side on which the maintenance area MA is disposed with respect to the printing area PA, is referred to as a "right " side, and the opposite side is referred to as a" left " side.
Seal holding units 213a to 213c for holding the seal member 250 are formed at an upper end of the main container 213. The seal holding units 213a to 213c are formed by bending an upper portion of the side wall of the main container 213 toward the outside, and are formed in a flat plate shape with the up and down direction as a thickness direction. In this modified example, three seal holding units 213a to 213c are formed in the main container 213. The seal holding unit 213a extends rightward from the upper end of the right side wall of the main container 213. The seal holding unit 213a is formed in an elongated rectangular shape with the front and rear direction as a long side direction. The seal holding unit 213b extends forward from the upper end of the front side wall of the main container 213. The seal holding unit 213c extends backward from the upper end of the rear side wall of the main container 213. The seal holding units 213b and 213c are formed in an elongated rectangular shape with the left and right direction as a long side direction.
The seal member 250 is a rubber packing formed of rubber. For example, the seal member 250 is formed of ethylene propylene diene rubber (EPDM) having excellent ink resistance. The seal member 250 is formed in an elongated linear shape. The seal member 250 is fitted into each of the seal holding units 213a to 213c from the outer peripheral side of the main container 213. That is, the moisturizing device 210 of this modified example includes three seal members 250. In the seal member 250, a slit-shaped engagement concave portion 250a (see Fig. 24(D)) to be fitted to the seal holding units 213a to 213c is formed. An upper portion of the seal member 250 is a seal portion 250b having a sealing function. The cross-sectional shape of the seal portion 250b is a hollow semicircular shape.
As described above, the seal member 250 is attached to the seal holding unit 213a extending rightward from the upper end of the right side wall of the main container 213, the seal holding unit 213b extending forward from the upper end of the front side wall of the main container 213, and the seal holding unit 213c extending backward from the upper end of the rear side wall of the main container 213. That is, the seal member 250 is disposed on the outer peripheral side of the main container 213. The seal member 250 is disposed at a position where the seal member can contact the outer peripheral end of the nozzle surface 204a on three sides of the rectangular nozzle surface 204a. Specifically, one seal member 250 is disposed at a position where the seal member can contact the entire right end side portion of the nozzle surface 204a, the other seal member 250 is disposed at a position where the seal member can contact substantially the entire front end side portion of the nozzle surface 204a, and the remaining one seal member 250 is disposed at a position where the seal member can contact substantially the entire rear end side portion of the nozzle surface 204a.
When the moisturizing device 210 moisturizes the nozzle surface 204a, the carriage 205 moves rightward to a position where the nozzle surface 204a is disposed above the main container 213. In this state, the head unit 204 is lowered by the lifting mechanism 245. When the head unit 204 descends, as illustrated in Fig. 24(B), the upper end of the seal member 250 comes into close contact with the nozzle surface 204a. That is, when the head unit 204 descends, the upper end of the seal portion 250b comes into contact with the nozzle surface 204a at a predetermined contact pressure. The upper end of the seal member 250 is in close contact with a portion of the nozzle surface 204a where the head 203 is not disposed.
An ink receiving portion 213d extending leftward is formed at the upper left end of the main container 213. The upper surface of the ink receiving portion 213d is an inclined surface inclined upward and leftward (see Fig. 24(C)). A wiping device (not illustrated) for wiping the nozzle surface 204a is disposed on the left side of the main container 213. The ink receiving portion 213d performs a function of receiving the ink dropped from the nozzle of the head 203 when the head unit 204 after performing the purge on the upper side of the main container 213 moves leftward and toward the wiping device.
In this modified example, the moisturizing device 210 includes a seal member 250 that can be brought into contact with the outer peripheral end of the nozzle surface 204a from below, and the seal member 250 is disposed on the outer peripheral side of the main container 213. Therefore, for example, even if the printer 201 is installed in a room where an air conditioner is used and the main container 213 is installed at a place where wind flows, the seal member 250 can suppress the wind from flowing from the gap between the upper end of the main container 213 and the nozzle surface 204a to the lower side of the nozzle surface 204a, and as a result, it is possible to suppress a decrease in humidity on the lower side of the nozzle surface 204a. Therefore, even if the main container 213 is installed at a place where wind flows, it is possible to suppress drying of the nozzle surface 204a caused by wind around the main container 213.
In particular, in this modified example, since the seal member 250 is disposed at a position where the seal member can contact the outer peripheral end of the nozzle surface 204a on both sides in the front and rear direction and three sides on the right side of the rectangular nozzle surface 204a, even if wind flows from the gap between the upper left end of the main container 213 and the nozzle surface 204a to the lower side of the nozzle surface 204a, it is possible to prevent the flowing wind from blowing out to both sides in the front and rear direction and the right side. Therefore, even if the main container 213 is installed at a place where wind flows, it is possible to effectively suppress a decrease in humidity on the lower side of the nozzle surface 204a due to the wind around the main container 213, and as a result, it is possible to effectively suppress drying of the nozzle surface 204a due to the wind around the main container 213.

(Modified example 2 of moisturizing device)

Fig. 25(A) is a plan view for illustrating a configuration of the main container 213 and the like according to another embodiment of the present invention, and Fig. 25(B) is a cross-sectional view taken along line J-J of Fig. 25(A). In Fig. 25, the same components as those in the above-described embodiment are denoted by the same reference numerals. In Fig. 25(B), illustration of the water absorbing member 214 and the holding member 222 is omitted.
In the modified example illustrated in Fig. 24, the seal holding units 213a to 213c may not be formed at the upper end of the main container 213. In this case, the moisturizing device 210 includes a cover member 254 disposed to surround the upper end of the main container 213, and a seal member 255 corresponding to the seal member 250 is fixed to the upper surface of the cover member 254. Specifically, the moisturizing device 210 includes the cover member 254 disposed on the right side of the upper end of the main container 213, the cover member 254 disposed on the front side of the upper end of the main container 213, and the cover member 254 disposed on the rear side of the upper end of the main container 213. The seal member 255 is fixed to the upper surface of the cover member 254 by, for example, a double-sided tape.
The seal member 255 is a rubber packing similar to the seal member 250, and is formed of, for example, EPDM. The cross-sectional shape of the seal member 255 is a hollow semicircular shape similarly to the cross-sectional shape of the seal portion 250b. As in the modified example illustrated in Fig. 24, the seal member 255 is disposed on the outer peripheral side of the main container 213. The seal member 255 is disposed at a position where the seal member can be brought into contact with the outer peripheral end of the nozzle surface 204a from below on three sides of the nozzle surface 204a having a rectangular shape.
A gap is formed between the upper end of the main container 213 and the cover member 254. That is, a gap is formed between the outer surface of the main container 213 and the end surface of the cover member 254. The moisturizing device 210 includes a second seal member 256 that closes a gap formed between the upper end of the main container 213 and the cover member 254. The second seal member 256 is, for example, an ept sealer. That is, the second seal member 256 is, for example, a sealing material formed of EPDM. As illustrated in Fig. 25(B), the second seal member 256 is fixed to the outer surface of the main container 213 and the lower surface of the cover member 254, and closes the gap between the upper end of the main container 213 and the cover member 254 from below.
When the moisturizing device 210 moisturizes the nozzle surface 204a, the head unit 204 descends after the carriage 205 moves rightward to a position where the nozzle surface 204a is disposed above the main container 213. When the head unit 204 descends, as illustrated in Fig. 25(B), the upper end of the seal member 255 comes into close contact with the nozzle surface 204a. Also in this modified example, the same effects as those of the modified example illustrated in Fig. 24 can be obtained. In this modified example, since the second seal member 256 closes the gap between the upper end of the main container 213 and the cover member 254, it is possible to prevent wind from flowing from the gap between the main container 213 and the cover member 254 to the lower side of the nozzle surface 204a even if a gap is formed between the main container 213 and the cover member 254.

(Modified example 3 of moisturizing device)

In the modified example illustrated in Figs. 24 and 25, the moisturizing device 210 may include four seal members 250 and 255 arranged at positions where the four sides of the nozzle surface 204a can contact the outer peripheral end of the nozzle surface 204a. That is, in addition to the three seal members 250 and 255 of the modified example illustrated in Figs. 24 and 25, the moisturizing device 210 may include seal members 250 and 255 arranged at positions where the seal members can contact the left end side portion of the nozzle surface 204a. In this case, a seal holding unit extending from the upper end of the left side wall of the main container 213 to the left side is formed in the main container 213. Alternatively, the cover member 254 is disposed on the left side of the upper end of the main container 213, and the seal member 255 is fixed to the upper surface of the cover member 254. In this case, the ink receiving portion 213d is not formed in the main container 213.
In this modified example, since the seal members 250 and 255 are arranged at positions where the four sides of the nozzle surface 204a can contact the outer peripheral end of the nozzle surface 204a, the four seal members 250 and 255 can prevent wind from flowing from the gap between the upper end of the main container 213 and the nozzle surface 204a to the lower side of the nozzle surface 204a. Therefore, even if the main container 213 is installed at a place where wind flows, it is possible to prevent a decrease in humidity on the lower side of the nozzle surface 204a due to the wind around the main container 213, and as a result, it is possible to prevent drying of the nozzle surface 204a due to the wind around the main container 213.
In the modified example illustrated in Figs. 24 and 25, the moisturizing device 210 may include two seal members 250 and 255 arranged at positions where the two sides of the nozzle surface 204a can contact the outer peripheral end of the nozzle surface 204a, or may include one seal member 250 or 255 disposed at a position where one side of the nozzle surface 204a can contact the outer peripheral end of the nozzle surface 204a. Further, in the modified example illustrated in Figs. 24 and 25, the outer shape of the nozzle surface 204a may be a quadrangular shape other than the rectangular shape, or may be a shape other than the quadrangular shape. Even in this case, the moisturizing device 210 includes a seal member that can be brought into contact with the outer peripheral end of the nozzle surface 204a from below, and the seal member is disposed on the outer peripheral side of the main container 213.

(Other embodiments)

The above-described embodiment is an example of a preferred embodiment of the present invention, but is not limited thereto, and various modifications can be made without changing the gist of the present invention.
In the embodiment described above, the sensors 239 to 241 may be sensors other than the magnetic sensor. In this case, the detection object detected by the sensors 239 to 241 other than the magnetic sensor is attached to the float 237. In the embodiment described above, the liquid level detection mechanism 218 may not include the sensor 241.
In the embodiment described above, the moisturizing liquid discharge unit 217 may include a pump that sends the moisturizing liquid M in the main container 213 to the waste liquid tank 232. In the embodiment described above, the moisturizing liquid M may be supplied from the liquid supply tank 228 to the main container 213 by the water head difference. In this case, the liquid supply tank 228 is disposed above the main container 213. Further, in the embodiment described above, the water absorbing member 214 may not be disposed in the main container 213. In the embodiment described above, the moisturizing device 210 may include a lifting mechanism that lifts and lowers the main container 213. In this case, the carriage 205 may not include the lifting mechanism 245. Furthermore, in the embodiment described above, the printer 201 may be a 3D printer that shapes a three-dimensional object, or may be an inkjet printer for general consumers.

REFERENCE SIGNS LIST

1: Printer
2: Medium
3: Printing mechanism
7: Winding roll
8: Winding roll holding unit
10: Heater
12: Tension applying mechanism
17: Head (inkjet head)
20: Platen
21: Suction mechanism
23: Intake port
24: Pipe
25: Suction fan
26: Filter
40: Tension bar
43: Guide portion
44: Tension coil spring (biasing member)
46: Slider
49: Linear scale
50, 51: Sensor
56: Tension bar support portion
61: Platen body
61a: Medium placement surface
62: Platen frame
X: Front and rear direction
Y: Left and right direction, width direction of medium
101: Printer (inkjet printer)
102: Medium
102A: Maximum width medium
104: Medium conveying mechanism
107: Winding roll
108: Winding roll holding unit
111: Head (inkjet head)
112: Carriage
113: Carriage driving mechanism
115: Platen
116: Suction mechanism
118: Maintenance unit
127a: Suction hole
128a: Intake hole
134: Exhaust fan
135: Suction fan
136: Flow path forming portion
136a: Flow path
137: Flow path forming frame
137a: Exhaust hole
138: Connection member
140: Filter
145: Heater
147: Tension applying mechanism
151: Tension bar
MA: Maintenance area
MR: Medium arrangement range
X: Front and rear direction
Y: Width direction and main scanning direction of medium
Y2: Maintenance area side
201: Printer (inkjet printer)
202: Medium
203: Head (inkjet head)
204: Head unit
204a: Nozzle surface
205: Carriage
206: Carriage driving mechanism
210: Moisturizing device
213: Main container
213a~213c: Seal holding unit
215: Sub-tank (sub-container)
216: Moisturizing liquid supply unit
217: Moisturizing liquid discharge unit
218: Liquid level detection mechanism
237: Float
238: Permanent magnet (detection object)
239~241: Sensor
250, 255: Seal member
254: Cover member
256: Second seal member
M: Moisturizing liquid
PA: Printing area

Claims

A printer comprising:
a printing mechanism which performs printing on a long medium;

a winding roll holding unit which holds a winding roll as the medium after printing wound in a roll shape; and

a tension applying mechanism which includes a tension bar coming into contact with the medium after printing between the printing mechanism and the winding roll holding unit to apply tension to the medium,

wherein a width direction of the medium coincides with a left and right direction orthogonal to an up and down direction,

wherein a thickness direction of the medium when printing is performed by the printing mechanism coincides with the up and down direction,

wherein the medium printed by the printing mechanism moves forward and then moves downward when a direction orthogonal to the up and down direction and the left and right direction is a front and rear direction,

wherein the tension bar is disposed below the printing mechanism, comes into contact with the medium moving downward from an obliquely rear and upper side, and applies tension to the medium by gravity acting on the tension bar, and

wherein the tension applying mechanism includes a guide portion that linearly guides the tension bar in a forward and downward direction, and a biasing member that biases the tension bar to an obliquely rear and upper side.
The printer as set forth in claim 1,
wherein the tension applying mechanism includes two of the guide portions and two of the biasing members,

wherein one guide portion guides a right end side of the tension bar,

wherein the other guide portion guides a left end side of the tension bar,

wherein one biasing member biases a right end of the tension bar, and

wherein the other biasing member biases a left end of the tension bar.
The printer as set forth in claim 2,
wherein the tension applying mechanism includes two sliders that are formed separately from the tension bar and are linearly movable in the same direction as a moving direction of the tension bar, and a linear scale and a sensor for detecting a position of the tension bar,

wherein the linear scale is fixed to one of the two sliders,

wherein one slider comes into contact with the right end of the tension bar from an obliquely front and lower side,

wherein the other slider comes into contact with the left end of the tension bar from the obliquely front and lower side, and

wherein the biasing member engages with the slider to bias the slider to an obliquely rear and upper side.
The printer as set forth in claim 3,
wherein the tension applying mechanism includes a tension bar support portion that is disposed above the guide portion and supports the tension bar separated from the guide portion.
The printer as set forth in any one of claims 1 to 4,
wherein the guide portion guides the tension bar in a direction inclined by 30° to 60° with respect to the front and rear direction when viewed from the left and right direction.
The printer as set forth in any one of claims 1 to 4, further comprising:
a heater for heating the medium after printing,

wherein the heater is disposed below and behind the tension bar,

wherein the winding roll is disposed above and behind the heater, and

wherein the medium having passed through the tension bar then passes above the heater and moves backward.
The printer as set forth in claim 6,
wherein the printing mechanism includes an inkjet head that ejects ink onto the medium, a platen on which the medium when printing is placed, and a suction mechanism that sucks and holds the medium placed on the platen onto the platen,

wherein the platen is disposed above the heater,

wherein the suction mechanism includes a plurality of intake ports arranged in the left and right direction, a suction fan connected to the plurality of intake ports via a pipe, and a filter that is disposed in the middle of a pipe path between the plurality of intake ports and the suction fan and through which air sucked from the plurality of intake ports passes, and

wherein the filter is disposed at a position shifted from the heater in a horizontal direction.
The printer as set forth in any one of claims 1 to 4,
wherein the printing mechanism includes an inkjet head that ejects ink onto the medium and a platen on which the medium when printing is placed,

wherein the platen includes a platen body provided with a medium placement surface on which the medium is placed, and a platen frame that supports the platen body from below,

wherein the platen body is formed of aluminum or an aluminum alloy, and

wherein at least the medium placement surface of a surface of the platen body is covered with a conductive coating.
The printer as set forth in claim 8,
wherein the coating is a plating coating.
The printer as set forth in claim 9,
wherein the plating coating is a nickel plating coating.
An inkjet printer for performing printing on a long medium, the inkjet printer comprising:
an inkjet head which ejects ink onto the medium;

a platen which is disposed below the inkjet head and on which the medium when printing is placed; and

a suction mechanism which sucks and holds the medium placed on the platen,

wherein a plurality of suction holes for sucking the medium placed on the platen are formed in an upper surface portion of the platen,

wherein the plurality of suction holes communicate with an internal space of the platen formed in a hollow shape,

wherein the suction mechanism includes an exhaust fan for discharging air in the internal space of the platen to the outside of the inkjet printer, and a flow path forming portion in which an air flow path through which the air discharged from the internal space of the platen passes is formed,

wherein when the medium having a widest width among the medium on which printing is performed by the inkjet printer is defined as a maximum width medium, and a range in which the maximum width medium is disposed in a width direction of the medium orthogonal to a thickness direction of the medium and a longitudinal direction of the medium is defined as a medium arrangement range, the exhaust fan is attached to the flow path forming portion,

wherein an exhaust hole through which air is discharged toward the outside of the inkjet printer by the exhaust fan is formed in the flow path forming portion, and

wherein the exhaust hole is disposed at a position deviated from the medium arrangement range in the width direction of the medium.
The inkjet printer as set forth in claim 11,
wherein the exhaust fan is disposed at the same position as the exhaust hole in the width direction of the medium.
The inkjet printer as set forth in claim 11 or 12, further comprising:
a carriage on which the inkjet head is mounted;

a carriage driving mechanism that reciprocates the carriage in a main scanning direction that is the width direction of the medium; and

a maintenance unit that prevents clogging of nozzles of the inkjet head,

wherein the maintenance unit is disposed in a maintenance area that is an area deviated from the medium arrangement range in the main scanning direction, and

wherein when a side on which the maintenance area is disposed with respect to the medium arrangement range in the main scanning direction is a maintenance area side, the exhaust hole is disposed on the maintenance area side with respect to the medium arrangement range.
The inkjet printer as set forth in claim 11 or 12,
wherein the suction mechanism includes a suction fan for sucking the medium placed on the platen,

wherein the suction fan is attached to a bottom surface of the platen,

wherein the flow path forming portion includes a hollow flow path forming frame that is formed in an elongated shape elongated in the width direction of the medium and in which the air flow path is formed, and a tubular connection member that connects the suction fan and the flow path forming frame, and

wherein the exhaust fan is attached to one end of the flow path forming frame in the width direction of the medium, and

wherein the exhaust hole is formed at the one end of the flow path forming frame in the width direction of the medium.
The inkjet printer as set forth in claim 14,
wherein the connection member is formed in a tubular shape by a thin film.
The inkjet printer as set forth in claim 11 or 12,
wherein the suction mechanism includes a filter through which air discharged from an internal space of the platen passes, and

wherein the filter is disposed at a position deviated from the medium arrangement range in the width direction of the medium.
The inkjet printer as set forth in claim 11 or 12,
wherein a plurality of intake holes arranged in the width direction of the medium are formed in a lower surface portion of the platen,

wherein the plurality of intake holes communicate with the internal space of the platen and communicate with the air flow path formed in the flow path forming portion, and

wherein the exhaust fan also has a function of sucking the medium placed on the platen.
The inkjet printer as set forth in claim 17, further comprising:
a medium conveying mechanism which conveys the medium in a longitudinal direction of the medium;

a winding roll holding unit which holds a winding roll as the medium after printing wound in a roll shape;

a tension applying mechanism which includes a tension bar coming into contact with the medium after printing between the inkjet head and the winding roll holding unit in a moving path of the medium to apply tension to the medium; and

a heater which heats the medium after printing,

wherein when a direction orthogonal to the width direction and an up and down direction of the medium is a front and rear direction,

a thickness direction of the medium when printing is performed by the inkjet head coincides with the up and down direction,

wherein the medium printed by the inkjet head moves forward and then moves downward,

wherein the tension bar is disposed below the platen, comes into contact with the medium moving downward from an obliquely rear and upper side, and applies tension to the medium by gravity acting on the tension bar,

wherein the heater is disposed below and behind the tension bar,

wherein the winding roll is disposed above and behind the heater,

wherein the medium having passed through the tension bar then passes above the heater and moves backward,

wherein the platen is disposed above the heater,

wherein the suction mechanism includes a filter through which air discharged from the internal space of the platen passes through the plurality of intake holes, and

wherein the filter is disposed at a position deviated from the medium arrangement range in the width direction of the medium, and is disposed at a position shifted from the heater in the width direction of the medium.
The inkjet printer as set forth in claim 11,
wherein the maximum width medium is a medium having a maximum width that can be printed by the inkjet printer.
A moisturizing device for moisturizing a nozzle surface of a head unit including a plurality of inkjet heads, comprising:
a main container that is formed in a box shape with an open upper surface and stores a moisturizing liquid for moisturization;

a sub-container that stores the moisturizing liquid and is connected to the main container;

a moisturizing liquid supply unit that supplies the moisturizing liquid to the main container; and

a liquid level detection mechanism that detects a height of a liquid level of the moisturizing liquid in the sub-container,

wherein a liquid level of the moisturizing liquid in the main container is disposed below the nozzle surface at a non-printing time when the inkjet head does not eject ink,

wherein the moisturizing liquid is able to flow between the main container and the sub-container,

wherein the height of the liquid level of the moisturizing liquid in the sub-container is equal to a height of the liquid level of the moisturizing liquid in the main container, and

wherein the moisturizing liquid supply unit supplies the moisturizing liquid to the main container based on a detection result of the liquid level detection mechanism.
The moisturizing device as set forth in claim 20, further comprising:
a moisturizing liquid discharge unit which discharges the moisturizing liquid from the main container,

wherein the moisturizing liquid discharge unit discharges the moisturizing liquid from the main container based on a detection result of the liquid level detection mechanism.
The moisturizing device as set forth in claim 20 or 21,
wherein the liquid level detection mechanism includes a float which floats in the moisturizing liquid in the sub-container, a detection object which is attached to the float, and a sensor which is disposed outside the sub-container and detects the detection object.
The moisturizing device as set forth in claim 20 or 21, further comprising:
a seal member that is brought into contact with an outer peripheral end of the nozzle surface from below,

wherein an outer shape of the nozzle surface is larger than an outer shape of the main container, and

wherein the seal member is disposed on an outer peripheral side of the main container.
The moisturizing device as set forth in claim 23,
wherein an outer shape of the nozzle surface is a rectangular shape, and

wherein the seal member is disposed at a position where the seal member is contactable with an outer peripheral end of the nozzle surface on at least three sides of the nozzle surface having a rectangular shape.
The moisturizing device as set forth in claim 23,
wherein a seal holding unit that holds the seal member is formed at an upper end of the main container.
The moisturizing device as set forth in claim 23, further comprising:
a cover member that is disposed to surround an upper end of the main container,

wherein the seal member is fixed to an upper surface of the cover member.
The moisturizing device as set forth in claim 26, further comprising:
a second seal member that closes a gap formed between the upper end of the main container and the cover member.
An inkjet printer comprising:
the moisturizing device as set forth in claim 20 or 21;

a head unit which includes the plurality of inkjet heads;

a carriage on which the head unit is mounted; and

a carriage driving mechanism which moves the carriage in a main scanning direction,

wherein the main container is disposed at a position deviated from a printing area that is an area where printing on a medium by the inkjet head is performed in the main scanning direction.