JP5601941B2 - Liquid supply device, liquid discharge device, and dew condensation prevention treatment method - Google Patents

Description

  The present invention relates to a liquid supply apparatus, a liquid discharge apparatus, and a dew condensation prevention processing method, and more particularly, to a temperature control technique for liquid supplied to an inkjet head.

  In the ink jet recording apparatus, the ejection characteristics of the head are maintained by supplying ink adjusted to a predetermined temperature range to the head. Further, there is a configuration in which ink whose temperature is adjusted is always supplied to the head by circulating the ink in the head to the outside. However, when the outside air flows into the apparatus when the environment outside the apparatus is high temperature and high humidity, there is a possibility that the head or ink flow path (tube) having the same temperature as the ink whose temperature has been adjusted may be condensed. .

  Patent Document 1 discloses a technique in which a piezoelectric vibrator is heated to at least a temperature higher than the surrounding temperature before printing is started in order to prevent the piezoelectric vibrator exposed to high humidity from dewing and malfunctioning. ing.

JP 2000-198193 A

  However, since the technique disclosed in Patent Document 1 independently determines the temperature and humidity, the temperature is higher than the temperature at which condensation is likely to occur and the humidity is lower than the humidity at which condensation is likely to occur. In the case where the temperature is lower than the temperature at which dehydration is likely to occur and the humidity is higher than the humidity at which dew condensation is liable to occur, the heat treatment of the piezoelectric vibrator is performed, so the environment in which the apparatus can be operated is greatly limited. In addition, since only the piezoelectric vibrator (head) is heated, there is a concern that dew condensation may occur in an ink flow path or the like other than the head when the apparatus is enlarged.

  The present invention has been made in view of such circumstances, and a liquid supply device, a liquid discharge device, and a dew condensation prevention in which the temperature of the ink is adjusted in accordance with the environment outside the device and the dew condensation around the head and its surroundings is prevented. An object is to provide a processing method.

In order to achieve the above object, a liquid supply apparatus according to the present invention includes a supply flow path for supplying a liquid to a liquid supply target, and a temperature of the liquid supplied to the liquid supply target within a predetermined temperature adjustment range. A temperature adjusting means for adjusting; a detecting means for detecting a temperature and humidity around the liquid supply target and the supply flow path; and a dew point temperature for deriving a dew point temperature based on the detected temperature and humidity. Dew condensation means, control means for controlling the temperature, and anti-condensation processing means for preventing dew condensation by preventing the dew point by making the temperature of the liquid equal to or higher than the derived dew point temperature. comprising setting means for setting the applied temperature, the said setting means, the temperature adjustment process of the temperature adjusting means is a cooling process, the lower limit of the temperature adjustment range, the temperature adjustment process of the temperature adjusting means A temperature control stop temperature set in advance as a temperature for stopping the condensation is set as a condensation prevention measure operating temperature that is a temperature for starting the condensation prevention measure, and the condensation prevention processing means includes the derived dew point temperature and The dew condensation prevention measure operation temperature is compared, and when the dew point temperature is equal to or higher than the dew condensation prevention measure operation temperature, the dew condensation prevention measure is executed.

  According to the present invention, the dew point temperature is derived based on the temperature and humidity around the apparatus, while the dew prevention measure operating temperature for stopping the temperature adjustment process is set, and the dew prevention measure is based on the derived dew point temperature. Since it is determined whether or not it is executed, the temperature and humidity range in which the apparatus can be operated becomes wider than when the temperature and humidity are independently determined and the anti-condensation measure is executed. At the same time, a preferable dew condensation prevention measure adapted to the temperature and humidity conditions around the apparatus is executed.

1 is an overall configuration diagram of an ink jet recording apparatus to which a liquid supply apparatus according to the present invention is applied. Plane perspective view showing a configuration example of an inkjet head mounted on the inkjet recording apparatus shown in FIG. FIG. 2 is a plan view for explaining the nozzle arrangement of the inkjet head shown in FIG. Sectional drawing which shows the three-dimensional structure of the inkjet head shown in FIG. 1 is a principal block diagram showing the system configuration of the ink jet recording apparatus shown in FIG. 1 is a principal block diagram showing the configuration of a circulating ink supply system applied to the ink jet recording apparatus shown in FIG. Diagram explaining dew point temperature table The flowchart which shows the flow of the dew condensation prevention processing method which concerns on 1st Embodiment of this invention. Illustration explaining the operating temperature for preventing condensation Diagram explaining dew condensation prevention measure release temperature The figure explaining the relationship between the condensation prevention measure operating temperature shown in FIG. 9 and the condensation prevention measure release temperature shown in FIG. The flowchart which shows the flow of the dew condensation prevention processing method which concerns on 2nd Embodiment of this invention.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[Overall configuration of inkjet recording apparatus]
FIG. 1 is a configuration diagram showing the overall configuration of an ink jet recording apparatus including a liquid supply apparatus according to an embodiment of the present invention. The ink jet recording apparatus 10 shown in the figure forms an image on the recording surface of the recording medium 14 based on predetermined image data using an ink containing a color material and an aggregating treatment liquid having a function of aggregating the ink. This is a two-liquid aggregation type recording apparatus.

  The ink jet recording apparatus 10 mainly includes a paper supply unit 20, a treatment liquid application unit 30, a drawing unit 40, a drying processing unit 50, a fixing processing unit 60, and a discharge unit 70. Although not shown in FIG. 1, an ink supply device that supplies ink to the drawing unit 40 is provided.

  Transfer cylinders 32, 42, 52, and 62 are provided as means for delivering the recording medium 14 conveyed upstream of the treatment liquid application unit 30, the drawing unit 40, the drying processing unit 50, and the fixing processing unit 60, and the treatment liquid. As means for conveying the recording medium 14 while holding the recording medium 14 in each of the coating unit 30, the drawing unit 40, the drying processing unit 50, and the fixing processing unit 60, impression cylinders 34, 44, 54, and 64 having a drum shape are provided. .

  The transfer cylinders 32 to 62 and the impression cylinders 34 to 64 are provided with grippers 80A and 80B that hold the leading end portion of the recording medium 14 at predetermined positions on the outer peripheral surface. The gripper 80A and the gripper 80B have the same structure for holding the tip of the recording medium 14 sandwiched between them, and the structure for transferring the recording medium 14 between grippers provided in other impression cylinders or transfer cylinders, and The gripper 80 </ b> A and the gripper 80 </ b> B are arranged at symmetrical positions that are moved 180 ° in the rotation direction of the pressure drum 34 on the outer peripheral surface of the pressure drum 34.

  When the transfer cylinders 32 to 62 and the impression cylinders 34 to 64 are rotated in a predetermined direction with the grippers 80A and 80B holding the leading end of the recording medium 14, the outer circumferences of the transfer cylinders 32 to 62 and the impression cylinders 34 to 64 are rotated. The recording medium 14 is rotated and conveyed along the surface.

  In FIG. 1, only the grippers 80 </ b> A and 80 </ b> B provided in the impression cylinder 34 are denoted by reference numerals, and the reference numerals of the other impression cylinders and the transfer cylinder grippers are omitted.

  When the recording medium (sheet) 14 accommodated in the paper supply unit 20 is fed to the treatment liquid application unit 30, the aggregation process is performed on the recording surface of the recording medium 14 held on the outer peripheral surface of the impression cylinder 34. A liquid (hereinafter simply referred to as “treatment liquid”) is applied. The “recording surface of the recording medium 14” is an outer surface in a state where the pressure drums 34 to 64 are held, and is a surface opposite to a surface held by the pressure drums 34 to 64.

  Thereafter, the recording medium 14 to which the aggregation treatment liquid has been applied is sent to the drawing unit 40, and color ink is applied to the area of the recording surface to which the aggregation treatment liquid has been applied, thereby forming a desired image.

  Further, the recording medium 14 on which the image of the color ink is formed is sent to the drying processing unit 50, where the drying processing unit 50 performs the drying processing, and after the drying processing, the recording medium 14 is sent to the fixing processing unit 60 to perform the fixing processing. Applied. By performing the drying process and the fixing process, the image formed on the recording medium 14 is hardened. In this way, a desired image is formed on the recording surface of the recording medium 14, and after the image is fixed on the recording surface of the recording medium 14, it is conveyed from the discharge unit 70 to the outside of the apparatus.

  Hereinafter, each part (the paper feeding unit 20, the processing liquid coating unit 30, the drawing unit 40, the drying processing unit 50, the fixing processing unit 60, and the discharging unit 70) of the inkjet recording apparatus 10 will be described in detail.

(Paper Feeder)
The paper feeding unit 20 is provided with a paper feeding tray 22 and a feeding mechanism (not shown), and the recording medium 14 is configured to be fed one by one from the paper feeding tray 22. The recording medium 14 sent out from the paper feed tray 22 is positioned by a guide member (not shown) so that its tip is positioned at a gripper (not shown) of the transfer drum (paper feed drum) 32 and temporarily stops.

(Processing liquid application part)
The processing liquid application unit 30 includes a processing liquid drum (processing liquid drum) 34 that holds the recording medium 14 delivered from the paper feed cylinder 32 on the outer peripheral surface and transports the recording medium 14 in a predetermined transport direction, and a processing liquid. A treatment liquid application unit 30 for applying a treatment liquid to the recording surface of the recording medium 14 held on the outer peripheral surface of the cylinder 34 is included. When the processing liquid cylinder 34 is rotated counterclockwise in FIG. 1, the recording medium 14 is rotated and conveyed in the counterclockwise direction along the outer peripheral surface of the processing liquid cylinder 34.

  The treatment liquid application unit 30 shown in FIG. 1 is provided at a position facing the outer peripheral surface (recording medium holding surface) of the treatment liquid cylinder 34. As a configuration example of the processing liquid application unit 30, a processing liquid container in which the processing liquid is stored, a pumping roller that is partially immersed in the processing liquid in the processing liquid container, and pumps up the processing liquid in the processing liquid container, and a pumping roller An embodiment including an application roller (rubber roller) that moves the pumped processing liquid onto the recording medium 14 is exemplified.

  In addition, an aspect is provided that includes an application roller moving mechanism that moves the application roller in the vertical direction (the normal direction of the outer peripheral surface of the treatment liquid cylinder 34), and can avoid collision between the application roller and the grippers 80A and 80B. preferable.

  The treatment liquid applied to the recording medium 14 by the treatment liquid application unit 30 contains a color material aggregating agent that aggregates the color material (pigment) in the ink applied by the drawing unit 40, and the treatment liquid is applied on the recording medium 14. And the ink come into contact with each other, the separation of the color material and the solvent in the ink is promoted.

  The treatment liquid application unit 30 is preferably applied while measuring the amount of the treatment liquid applied to the recording medium 14, and the film thickness of the treatment liquid on the recording medium 14 is determined by the ink droplets ejected from the drawing unit 40. It is preferable to make it sufficiently smaller than the diameter.

(Drawing part)
The drawing unit 40 includes a drawing cylinder (drawing drum) 44 that holds and transports the recording medium 14, a paper pressing roller 46 that brings the recording medium 14 into close contact with the drawing cylinder 44, and an inkjet that applies ink to the recording medium 14. Heads 48M, 48K, 48C, and 48Y are provided. The basic structure of the drawing cylinder 44 is the same as that of the processing liquid cylinder 34 described above, but grippers 80A and 80B that sandwich the leading end of the recording medium 14 are arranged so as not to protrude from the peripheral surface. It is structurally different.

  The sheet pressing roller 46 is a guide member for bringing the recording medium 14 into close contact with the outer peripheral surface of the drawing cylinder 44, faces the outer peripheral surface of the drawing cylinder 44, and delivers the recording medium 14 between the transfer cylinder 42 and the drawing cylinder 44. It is disposed downstream of the position in the transport direction of the recording medium 14 and upstream of the ink jet heads 48M, 48K, 48C, and 48Y in the transport direction of the recording medium 14.

  Further, a paper floating detection sensor (not shown) is disposed between the paper pressing roller 46 and the most upstream ink jet head 48Y in the conveyance direction of the recording medium 14. The sheet floating detection sensor detects the amount of floating immediately before the recording medium 14 enters just below the inkjet heads 48M, 48K, 48C, 48Y. In the ink jet recording apparatus 10 shown in this example, when the floating amount of the recording medium 14 detected by the paper floating detection sensor exceeds a predetermined threshold, the fact is notified and the conveyance of the recording medium 14 is interrupted. It is configured as follows.

  The recording medium 14 transferred from the transfer cylinder 42 to the drawing cylinder 44 is pressed by the sheet pressing roller 46 when being rotated and conveyed with the leading end held by a gripper (reference numeral omitted), and the outer periphery of the drawing cylinder 44. Adhere to the surface. In this manner, after the recording medium 14 is brought into close contact with the outer peripheral surface of the drawing cylinder 44, the recording medium 14 is sent to the printing area immediately below the ink jet heads 48M, 48K, 48C, 48Y without being lifted from the outer peripheral surface of the drawing cylinder 44. It is done.

  The inkjet heads 48M, 48K, 48C, and 48Y correspond to inks of four colors, magenta (M), black (K), cyan (C), and yellow (Y), respectively, and the rotation direction of the drawing cylinder 44 (see FIG. 1 (counterclockwise direction in FIG. 1) in order from the upstream side, and the ink ejection surfaces (nozzle surfaces) of the inkjet heads 48M, 48K, 48C, 48Y are opposed to the recording surface of the recording medium 14 held by the drawing cylinder 44. To be arranged. The “ink ejection surface (nozzle surface)” is a surface of the inkjet heads 48M, 48K, 48C, and 48Y that faces the recording surface of the recording medium 14, and is a nozzle that ejects ink (described in FIG. 3). This is a surface on which is formed.

  Further, in the inkjet heads 48M, 48K, 48C, 48Y shown in FIG. 1, the recording surface of the recording medium 14 held on the outer peripheral surface of the drawing cylinder 44 and the nozzle surfaces of the inkjet heads 48M, 48K, 48C, 48Y are substantially parallel. In such a manner, it is arranged to be inclined with respect to the horizontal plane.

  The inkjet heads 48M, 48K, 48C, and 48Y are full-line heads having a length corresponding to the maximum width of the image forming area in the recording medium 14 (the length in the direction orthogonal to the conveyance direction of the recording medium 14). The recording medium 14 is fixedly installed so as to extend in a direction orthogonal to the conveyance direction of the recording medium 14. Ink jet heads 48M, 48K, 48C, and 48Y are each supplied with ink from an ink supply device that will be described in detail later.

  On the nozzle surfaces (liquid ejection surfaces) of the inkjet heads 48M, 48K, 48C, and 48Y, ink ejection nozzles are formed in a matrix arrangement over the entire width of the image forming area of the recording medium 14.

  When the recording medium 14 is conveyed to the printing area immediately below the ink jet heads 48M, 48K, 48C, 48Y, the image data is converted into the area where the aggregation processing liquid of the recording medium 14 is applied from the ink jet heads 48M, 48K, 48C, 48Y. Based on this, ink of each color is ejected (droplet ejection).

  When droplets of the corresponding color ink are ejected from the inkjet heads 48M, 48K, 48C, 48Y toward the recording surface of the recording medium 14 held on the outer peripheral surface of the drawing cylinder 44, the processing is performed on the recording medium 14. The liquid and the ink come into contact with each other, and an aggregation reaction of the color material (pigment-based color material) dispersed in the ink or the color material (dye-based color material) to be insolubilized appears, and a color material aggregate is formed. As a result, movement of the color material in the image formed on the recording medium 14 (dot misalignment, dot color unevenness) is prevented.

  In addition, since the drawing cylinder 44 of the drawing unit 40 is structurally separated from the processing liquid cylinder 34 of the processing liquid application unit 30, the processing liquid does not adhere to the ink jet heads 48M, 48K, 48C, and 48Y. In addition, the cause of abnormal ink ejection can be reduced.

  In this example, the configuration of MKCY standard colors (four colors) is illustrated, but the combination of ink colors and the number of colors is not limited to this embodiment, and light ink, dark ink, and special colors are used as necessary. Ink may be added. For example, it is possible to add an inkjet head that discharges light-colored ink such as light cyan and light magenta, and the arrangement order of the color heads is not particularly limited.

  Ink used for the inkjet heads 48M, 48K, 48C, and 48Y is subjected to a temperature adjustment process so as to be within a predetermined temperature range in order to ensure good ejection characteristics. In addition, the drawing unit 40 (particularly, the vicinity of the inkjet heads 48M, 48K, 48C, and 48Y) is temperature-adjusted (cooling process) so as to be substantially the same as the temperature range of the ink, and the processing liquid is dried. Further, condensation is prevented when a relatively high temperature recording medium is used.

  Furthermore, the inkjet recording apparatus 10 shown in this example includes a detection device 90 that detects the temperature and humidity of the outside air in the installation environment, and a dew condensation prevention measure is executed based on the detection result of the detection device 90 (details will be described later). ). The detection device 90 includes a temperature sensor and a humidity sensor, and is provided outside a cover (not shown) that covers the drawing unit 40.

(Dry processing part)
The drying processing unit 50 includes a drying drum (drying drum) 54 that holds and conveys the recording medium 14 after image formation, and a drying processing device 56 that performs a drying process for evaporating moisture (liquid component) on the recording medium 14. It has. Note that the basic structure of the drying cylinder 54 is the same as that of the processing liquid cylinder 34 and the drawing cylinder 44 described above, and a description thereof will be omitted here.

  The drying processing device 56 is a processing unit that is disposed at a position facing the outer peripheral surface of the drying drum 54 and evaporates moisture present in the recording medium 14. When ink is applied to the recording medium 14 by the drawing unit 40, the liquid component (solvent component) of the ink and the liquid component (solvent component) of the processing liquid separated by the aggregation reaction between the processing liquid and the ink are placed on the recording medium 14. Since it remains, it is necessary to remove such a liquid component.

  The drying processing device 56 performs a drying process for evaporating a liquid component existing on the recording medium 14 by heating with a heater, blowing with a fan, or a combination thereof, and a process for removing the liquid component on the recording medium 14. Part. The amount of heating and the amount of air supplied to the recording medium 14 are appropriately set according to parameters such as the amount of moisture remaining on the recording medium 14, the type of the recording medium 14, and the conveyance speed (drying processing time) of the recording medium 14. Is done.

  When the drying processing by the drying processing device 56 is performed, the drying cylinder 54 of the drying processing unit 50 is structurally separated from the drawing cylinder 44 of the drawing unit 40, so that the inkjet heads 48M, 48K, 48C, 48Y. In this case, it is possible to reduce the cause of abnormal ink ejection due to drying of the head meniscus by heat or air blowing.

  In order to exhibit the cockling correction effect of the recording medium 14, the curvature of the drying cylinder 54 is preferably 0.002 (1 / mm) or more. In order to prevent the recording medium from being curved (curled) after the drying process, the curvature of the drying cylinder 54 is preferably set to 0.0033 (1 / mm) or less.

  In addition, a means (for example, a built-in heater) for adjusting the surface temperature of the drying drum 54 may be provided, and the surface temperature may be adjusted to 50 ° C. or higher. By applying heat treatment from the back surface of the recording medium 14, drying is promoted and image destruction during the subsequent fixing process is prevented. In such an embodiment, it is more effective to provide means for bringing the recording medium 14 into close contact with the outer peripheral surface of the drying drum 54. Examples of the means for bringing the recording medium 14 into close contact include vacuum suction and electrostatic suction.

  The upper limit of the surface temperature of the drying cylinder 54 is not particularly limited, but from the viewpoint of safety of maintenance work such as cleaning ink adhering to the surface of the drying cylinder 54 (preventing burns due to high temperature). It is preferably set to 75 ° C. or lower (more preferably 60 ° C. or lower).

  The recording drum 14 is held on the outer peripheral surface of the drying drum 54 configured in this manner so that the recording surface of the recording medium 14 faces outward (that is, in a state where the recording surface of the recording medium 14 is convex). By performing the drying process while rotating and transporting, drying unevenness due to wrinkling and floating of the recording medium 14 is surely prevented.

(Fixing processing part)
The fixing processing unit 60 includes a fixing cylinder (fixing drum) 64 that holds and conveys the recording medium 14, a heater 66 that heats the recording medium 14 on which an image is formed and from which the liquid is removed, and the recording And a fixing roller 68 that presses the medium 14 from the recording surface side. The basic structure of the fixing cylinder 64 is the same as that of the processing liquid cylinder 34, the drawing cylinder 44, and the drying cylinder 54, and the description thereof is omitted here. The heater 66 and the fixing roller 68 are arranged at a position facing the outer peripheral surface of the fixing cylinder 64, and are sequentially arranged from the upstream side in the rotation direction of the fixing cylinder 64 (counterclockwise direction in FIG. 1).

  In the fixing processing unit 60, the recording surface of the recording medium 14 is subjected to a preheating process by the heater 66 and a fixing process by the fixing roller 68. The heating temperature of the heater 66 is appropriately set according to the type of recording medium, the type of ink (the type of polymer fine particles contained in the ink), and the like. For example, a mode in which the glass transition temperature and the minimum film forming temperature of the polymer fine particles contained in the ink are considered.

  The fixing roller 68 is a roller member for heating and pressurizing the dried ink to weld the self-dispersing polymer fine particles in the ink to form a film of the ink, and is configured to heat and press the recording medium 14. The Specifically, the fixing roller 68 is disposed so as to be in pressure contact with the fixing cylinder 64 and constitutes a nip roller with the fixing cylinder 64. As a result, the recording medium 14 is sandwiched between the fixing roller 68 and the fixing cylinder 64 and is nipped at a predetermined nip pressure, so that the fixing process is performed.

  As an example of the configuration of the fixing roller 68, there is an embodiment in which the fixing roller 68 is configured by a heating roller in which a halogen lamp is incorporated in a metal pipe such as aluminum having good thermal conductivity. By heating the recording medium 14 with such a heating roller, when thermal energy equal to or higher than the glass transition temperature of the polymer fine particles contained in the ink is applied, the polymer fine particles are melted to form a transparent film on the surface of the image. Is done.

  When pressure is applied to the recording surface of the recording medium 14 in this state, the polymer fine particles melted into the unevenness of the recording medium 14 are pressed and fixed, and the unevenness of the image surface is leveled, so that preferable glossiness can be obtained. A configuration in which a plurality of fixing rollers 68 are provided in accordance with the thickness of the image layer and the glass transition temperature characteristics of the polymer particles is also preferable.

  The surface hardness of the fixing roller 68 is preferably 71 ° or less. By making the surface of the fixing roller 68 softer, a follow-up effect can be expected for the unevenness of the recording medium 14 caused by cockling, and fixing unevenness due to the unevenness of the recording medium 14 can be more effectively prevented. .

  In the ink jet recording apparatus 10 shown in FIG. 1, an inline sensor 82 is provided at a subsequent stage (downstream in the recording medium conveyance direction) of the processing area of the fixing processing unit 60. The in-line sensor 82 is a sensor for reading an image formed on the recording medium 14 (or a check pattern formed in a blank area of the recording medium 14), and a CCD line sensor is preferably used.

  In the ink jet recording apparatus 10 shown in this example, the presence or absence of ejection abnormality of the ink jet heads 48M, 48K, 48C, and 48Y is determined based on the reading result of the inline sensor 82. Further, the in-line sensor 82 may include a measuring unit for measuring the moisture content, the surface temperature, the glossiness, and the like. In such an embodiment, parameters such as the processing temperature of the drying processing unit 50, the heating temperature of the fixing processing unit 60, and the pressure pressure are appropriately adjusted based on the moisture content, surface temperature, and gloss reading result, and the temperature inside the apparatus. The control parameter is adjusted as appropriate in accordance with the change and the temperature change of each part.

(Discharge part)
As shown in FIG. 1, a discharge unit 70 is provided following the fixing processing unit 60. The discharge unit 70 includes an endless transport chain 74 wound around the stretching rollers 72A and 72B, and a discharge tray 76 that stores the recording medium 14 after image formation.

  The recording medium 14 after the fixing process sent out from the fixing processing unit 60 is transported by the transport chain 74 and discharged to the discharge tray 76.

[Inkjet head structure]
Next, an example of the structure of the inkjet heads 48M, 48K, 48C, 48Y provided in the drawing unit 40 will be described. Since the structures of the ink jet heads 48M, 48K, 48C, and 48Y corresponding to the respective colors are common, the ink jet head (hereinafter also simply referred to as “head”) is denoted by reference numeral 100 in the following. And

  FIG. 2 is a schematic configuration diagram of the inkjet head 100, which is a diagram (a plan perspective view of the head) of the recording surface of the recording medium as viewed from the inkjet head 100. The head 100 shown in the figure forms a multi-head by connecting n head modules 102-i (i is an integer from 1 to n) in a line along the longitudinal direction of the head 100. Each head module 102-i is supported by head covers 104 and 106 from both sides of the head 100 in the short direction. It is also possible to configure a multi-head by arranging the head modules 102 in a staggered manner.

  As an application example of a multi-head configured by a plurality of sub-heads, a full-line head corresponding to the entire width of a recording medium can be given. The full-line head has a plurality of nozzles (FIG. 3) corresponding to the length (width) in the main scanning direction of the recording medium in the direction (main scanning direction) orthogonal to the moving direction (sub-scanning direction) of the recording medium. Are attached with a reference numeral 108).) Are arranged. An image can be formed on the entire surface of the recording medium by a so-called single-pass image recording method in which image recording is performed by scanning the head 100 having such a structure and the recording medium only once relatively.

  The head module 102-i constituting the head 100 has a substantially parallelogram-shaped planar shape, and an overlap portion is provided between adjacent sub-heads. The overlap portion is a connecting portion of the sub heads, and is formed by nozzles in which adjacent dots belong to different sub heads in the arrangement direction of the head modules 102-i.

  FIG. 3 is a plan view showing the nozzle arrangement of the head module 102-i. As shown in the figure, each head module 102-i has a structure in which nozzles 108 are arranged two-dimensionally, and a head including such a head module 102-i is a so-called matrix head. . The head module 102-i shown in FIG. 3 includes a number of nozzles 108 along a column direction W that forms an angle α with respect to the sub-scanning direction Y and a row direction V that forms an angle β with respect to the main scanning direction X. It has an aligned structure, and the substantial nozzle arrangement density in the main scanning direction X is increased. In FIG. 3, nozzle groups (nozzle rows) arranged along the row direction V are denoted by reference numeral 110, and nozzle groups (nozzle rows) arranged along the column direction W are denoted by reference numeral 112. ing.

  Another example of the matrix arrangement of the nozzles 108 is a configuration in which a plurality of nozzles 108 are arranged along the row direction along the main scanning direction X and the column direction oblique to the main scanning direction X.

  FIG. 4 is a cross-sectional view showing a three-dimensional configuration of one channel of droplet discharge elements (ink chamber units corresponding to one nozzle 108) serving as a recording element unit. As shown in the figure, in the head 100 of this example, a nozzle plate 114 formed with nozzles 108 and a flow path plate 120 formed with flow paths such as a pressure chamber 116 and a common flow path 118 are laminated and joined. Consists of structure. The nozzle plate 114 forms a nozzle surface 114A of the head 100, and a plurality of nozzles 108 communicating with the pressure chambers 116 are two-dimensionally formed.

  The flow path plate 120 constitutes a side wall portion of the pressure chamber 116 and a flow path forming a supply port 122 as a throttle portion (most narrowed portion) of an individual supply path that guides ink from the common flow path 118 to the pressure chamber 116. It is a forming member. For convenience of explanation, although shown in FIG. 4 in a simplified manner, the flow path plate 120 has a structure in which one or a plurality of substrates are stacked.

  The nozzle plate 114 and the flow path plate 120 can be processed into a required shape by a semiconductor manufacturing process using silicon as a material.

  The common flow path 118 communicates with an ink tank (not shown) serving as an ink supply source, and ink supplied from the ink tank is supplied to each pressure chamber 116 via the common flow path 118.

  A diaphragm 124 constituting a part of the pressure chamber 116 (the top surface in FIG. 4) includes an individual electrode 126 and a lower electrode 128, and the piezoelectric body 130 is interposed between the individual electrode 126 and the lower electrode 128. A piezo actuator 132 having a sandwiched structure is joined. When the diaphragm 124 is formed of a metal thin film or a metal oxide film, it functions as a common electrode corresponding to the lower electrode 128 of the piezoelectric actuator 132. In the aspect in which the diaphragm is formed of a non-conductive material such as resin, a lower electrode layer made of a conductive material such as metal is formed on the surface of the diaphragm member.

  By applying a driving voltage to the individual electrode 126, the piezo actuator 132 is deformed to change the volume of the pressure chamber 116, and ink is ejected from the nozzle 108 due to a pressure change accompanying this. When the piezo actuator 132 returns to its original state after ink ejection, new ink is refilled into the pressure chamber 116 from the common flow path 118 through the supply port 122.

As shown in FIG. 3, the ink chamber unit having such a structure is latticed in a fixed arrangement pattern along a row direction V that forms an angle β with the main scanning direction X and a column direction W that forms an angle α with respect to the sub-scanning direction Y. The high-density nozzle head of this example is realized by arranging a large number in the shape. In this matrix arrangement, when the interval between adjacent nozzles in the sub-scanning direction Y is L _s , the nozzles 108 are substantially linearly arranged at a constant pitch P = L _s / tan θ in the main scanning direction X. Can be handled equivalently.

  In this example, the piezo actuator 132 is applied as a means for generating ink ejection force to be ejected from the nozzles 108 provided in the head 100. However, a heater is provided in the pressure chamber 116 and the pressure of film boiling caused by heating of the heater is used. It is also possible to apply a thermal method that ejects ink.

[Explanation of control system]
FIG. 5 is a block diagram illustrating a schematic configuration of a control system of the inkjet recording apparatus 10. The inkjet recording apparatus 10 includes a communication interface 140, a system control unit 142, a conveyance control unit 144, an image processing unit 146, a head driving unit 148, and an image memory 150 and a ROM 152.

  The communication interface 140 is an interface unit that receives image data sent from the host computer 154. The communication interface 140 may be a serial interface such as USB (Universal Serial Bus) or a parallel interface such as Centronics. The communication interface 140 may include a buffer memory (not shown) for speeding up communication.

  The system control unit 142 includes a central processing unit (CPU) and its peripheral circuits, and functions as a control device that controls the entire inkjet recording apparatus 10 according to a predetermined program, and also functions as an arithmetic device that performs various calculations. Furthermore, it functions as a memory controller for the image memory 150 and the ROM 152. That is, the system control unit 142 controls each unit such as the communication interface 140 and the conveyance control unit 144, performs communication control with the host computer 154, read / write control of the image memory 150 and the ROM 152, and the above-described units. A control signal to be controlled is generated.

  Image data sent from the host computer 154 is taken into the ink jet recording apparatus 10 via the communication interface 140, and predetermined image processing is performed by the image processing unit 146.

  The image processing unit 146 has a signal (image) processing function for performing various processing and correction processes for generating a print control signal from the image data, and supplies the generated print data to the head drive unit 148. It is a control unit. The required signal processing is performed in the image processing unit 146, and the ejection droplet amount (droplet ejection amount) of the head 100 and ejection timing are controlled via the head driving unit 148 based on the image data. Thereby, a desired dot size and dot arrangement are realized. The head driving unit 148 shown in FIG. 5 may include a feedback control system for keeping the driving conditions of the head 100 constant.

  The head drive unit 148 includes a drive waveform generation unit that generates a drive waveform, an amplification unit that amplifies the drive waveform to generate a drive voltage, and a drive voltage supply unit that supplies a drive voltage having a predetermined drive waveform to the head And. A drive waveform is generated based on image data (digital data) sent from the system control unit (or a corresponding drive waveform is selected from the drive waveforms stored in advance), and the drive voltage having the drive waveform is Generated.

  The conveyance control unit 144 controls the conveyance timing and conveyance speed of the recording medium 14 (see FIG. 1) based on the print control signal generated by the image processing unit 146. The conveyance drive unit 156 in FIG. 5 includes a motor that rotates the impression cylinders 34 to 64 in FIG. 1, a motor that rotates the transfer cylinders 32 to 62, a motor of the feeding mechanism of the recording medium 14 in the sheet feeding unit 20, and a discharge unit 70. A motor for driving the tension roller 72A (72B) is included, and the conveyance control unit 144 functions as a driver for the motor.

  An image memory (primary storage memory) 150 functions as a primary storage unit that temporarily stores image data input via the communication interface 140, a development area for various programs stored in the ROM 152, and a calculation work area for the CPU. (For example, a work area of the image processing unit 146). As the image memory 150, a volatile memory (RAM) capable of sequential reading and writing is used.

  The ROM 152 stores a program executed by the CPU of the system control unit 142, various data necessary for control of each unit of the apparatus, control parameters, and the like, and data is read and written through the system control unit 142. The ROM 152 is not limited to a memory made of a semiconductor element, and a magnetic medium such as a hard disk may be used. Alternatively, a removable storage medium that includes an external interface may be used.

  Further, the inkjet recording apparatus 10 includes a processing liquid application control unit 160, a drying processing control unit 162, and a fixing processing control unit 164. According to instructions from the system control unit 142, the processing liquid application unit 30, The operation of each part of the drying processing unit 50 and the fixing processing unit 60 is controlled.

  Based on the print data obtained from the image processing unit 146, the processing liquid application control unit 160 controls the processing liquid application timing by the processing liquid application unit 30 and also controls the application amount of the processing liquid. In addition, the drying processing control unit 162 controls the timing of the drying processing in the drying processing device 56 (see FIG. 1) included in the drying processing unit 50, controls the processing temperature, the air flow rate, and the like, and the fixing processing control unit 164. Controls the temperature of the heater 66 (see FIG. 1) included in the fixing processing unit 60 and also controls the pressing of the fixing roller 68 (see FIG. 1).

  The inline detection unit 166 including the inline sensor 82 illustrated in FIG. 1 is a processing block including a signal processing unit that performs predetermined signal processing such as nozzle removal, amplification, and waveform shaping on the read signal output from the inline sensor 82. . The system control unit 142 determines whether there is an ejection abnormality of the head 100 based on the detection signal obtained by the inline detection unit.

  The ink supply control unit 168 controls ink supply to the head 100 by the ink supply unit 200. The ink temperature adjuster 278 is included in the ink supply unit 200 and adjusts the temperature of the ink so that the ink supplied from the ink supply unit 200 to the head 100 is maintained in a predetermined temperature range.

  The deaeration control unit 178 is included in the ink supply unit 200, and performs a deaeration process on the ink sent from the ink tank (not shown in FIG. 5 and indicated by reference numeral 201 in FIG. 6) to the head 100. The operation of the Qi module 276 is controlled.

  The inkjet recording apparatus 10 shown in this example includes a user interface 170, and the user interface 170 includes an input device 172 for an operator (user) to make various inputs and a display unit (display) 174. The The input device 172 can employ various forms such as a keyboard, a mouse, a touch panel, and buttons. By operating the input device 172, the operator can perform input of printing conditions, selection of image quality mode, input / editing of attached information, search of information, and various information such as input contents and search results. This can be confirmed through the display on the display unit 174. The display unit 174 also functions as means for displaying a warning such as an error message.

  The parameter storage unit 180 stores various control parameters necessary for the operation of the inkjet recording apparatus 10. The system control unit 142 appropriately reads out parameters necessary for control and updates (rewrites) various parameters as necessary.

  The pressure sensors 206 and 216 include a pressure detection element for measuring the pressure in the ink flow path (not shown in FIG. 5 and indicated by reference numerals 202 and 212 in FIG. 6). The signal is converted into a signal and provided to the system control unit 142. The system control unit 142 sends a command signal to the ink supply control unit 168 so as to correct the operation (rotational speed) of the supply side pump 210 and the recovery side pump 220 included in the ink supply unit 200 based on the pressure information. .

  The program storage unit 184 is a storage unit that stores a control program for operating the inkjet recording apparatus 10. This control program includes control programs such as the supply-side pump 210 and the recovery-side pump 220, the deaeration module 276, and the ink temperature adjuster 278 that are included in the ink supply unit 200.

  The temperature sensor 90A and the humidity sensor 90B illustrated in FIG. 5 are included in the detection device 90 illustrated in FIG. The temperature sensor 90A detects the temperature of the outside air of the apparatus, the humidity sensor 90B detects the humidity of the outside air of the apparatus, and the temperature information obtained from the temperature sensor 90A and the humidity information obtained from the humidity sensor 90B are the system control unit. 142. The system control unit 142 sends a command signal to each unit of the apparatus so as to execute a dew condensation prevention measure based on the temperature information and humidity information. Details of the dew condensation prevention measure will be described later.

(Description of ink supply device)
6 is a block diagram illustrating a schematic configuration of an ink supply unit 200 that supplies ink of each color to each of the inkjet heads 48M, 48K, 48C, and 48Y (head 100 in FIG. 5) illustrated in FIG. The ink supply unit 200 shown in the figure supplies ink from the ink tank 201 (the main tank 201A and the buffer tank 201B) to the head 100, and from the head 100 to the ink tank 201 via the circulation (collection) channel 212. This is a circulation type ink supply unit for circulating ink. The ink supply unit 200 employs a system in which a differential pressure is provided between the supply side sub tank 208 and the recovery side sub tank 218 provided in the supply flow path 202 so that the ink is circulated through the head 100.

  The ink supply unit 200 illustrated in FIG. 6 includes an ink tank 201, a supply channel 202 that communicates with the ink tank, a supply side manifold 203 that communicates with the supply channel 202, and the supply side manifold 203 and the head 100. A supply-side valve 204 for switching between communication and non-communication, an air damper 205 provided between the supply-side valve 204 and the head 100, and an air damper 215 provided between the head 100 and the recovery-side manifold 213; A collection side valve 214, and a circulation channel 212 for communicating the collection side manifold 213 and the ink tank 201 are provided.

  The ink tank 201 includes a main tank 201A and a buffer tank 201B. When the replenishment pump 274 provided between the main tank 201A and the buffer tank 201B is operated, foreign matter is removed from the ink stored in the main tank 201A by the filter 201C inside the main tank 201A, and the ink is sent to the buffer tank 201B. It is done.

  The supply flow path 202 includes a deaeration module 276, a one-way valve 280, a supply-side pump 210, a filter 284, an ink temperature regulator (heat exchanger) 278, and a sub tank (pressure buffer chamber) 208. ing. When the supply-side pump 210 is operated, ink is sucked up from the buffer tank 201B, degassed by the degassing module 276, and foreign matter is removed by the filter 284. Then, the ink temperature adjuster 278 performs a predetermined temperature range. The temperature is adjusted to (for example, 20 ° C. or more and 35 ° C. or less) and sent to the supply side manifold 203 via the supply side sub tank 208.

  The supply side manifold 203 is a primary storage chamber portion of the ink supplied to the head 100, and individually communicates with each of the head modules 102 (102-1 to 102-n) constituting the head 100, and the supply side valve 204. (204-1 to 204-n) can be operated to individually switch between communication and non-communication. Air dampers 205 (205-1 to 205-n) are individually provided between the supply side valve 204 and each head module 102.

  The supply side manifold 203 is provided with a pressure sensor 206 for detecting pressure. The pressure sensor 206 includes a sensor element such as a semiconductor piezoresistive method, a capacitance method, or a silicon resonant method, and the measured pressure information is converted into an electrical signal and sent to the system control unit 142 in FIG. The control information of the supply side pump 210 and the recovery side pump 220 is used.

  The supply-side subtank 208 has a structure partitioned (separated) into a liquid chamber 208B and an air chamber 208C by an elastic separation membrane 208A. The air chamber 208 </ b> C is configured to communicate with the atmosphere via the atmosphere communication path 238 and the atmosphere communication valve 240.

  The supply-side subtank 208 deforms the elastic separation membrane 208A in response to pressure fluctuations in the supply flow path 202 (fluctuation in the amount of liquid fed) to vary the volume of the liquid chamber 208B, thereby buffering pressure fluctuations in the supply flow path 202. It has a function. The supply-side sub tank 208 communicates with the buffer tank 201B via the drain flow path 228 and the drain valve 230. When the drain valve 230 is opened, the ink in the liquid chamber 208B is discharged to the buffer tank 201B. .

  The supply side pump 210 is a tube pump capable of switching between forward and reverse rotation. The supply-side pump 210 is connected to a return flow path that communicates with the buffer tank 201B via the one-way valve 283. For example, when the supply-side pump 210 is rotated forward, the supply-side pump 210 moves from the buffer tank 201B to the head 100. When the heading direction is the ink feeding direction and the supply-side pump 210 is operated in reverse, the direction from the head 100 toward the buffer tank 201B can be the ink feeding direction. That is, by switching between forward and reverse rotation of the supply-side pump 210, the amount of ink fed from the supply-side pump 210 to the supply channel 202 can be adjusted, and the pressure in the supply channel 202 is adjusted.

  As shown in FIG. 6, the supply side manifold 203 and the recovery side manifold 213 communicate with each other via the first bypass flow path 270 and the first bypass flow path valve 272, and the second bypass flow path 271. And it has the structure connected via the 2nd bypass flow path valve 273. That is, when the first bypass flow path valve 272 or the second bypass flow path valve 273 is opened, the supply side manifold 203 and the recovery side manifold 213 can be communicated with each other. In addition, the ink can be circulated from the recovery side manifold 213 to the supply side manifold 203.

  With this structure, the ink in the supply side manifold 203 and the ink in the recovery side manifold 213 do not stay, and the occurrence of temperature distribution in the supply side manifold 203 and the recovery side manifold 213 is suppressed.

  A circulation system that circulates ink from the head 100 to the buffer tank 201B has a structure common to the above-described supply system. The recovery side valve 214 (214-1 to 214-n) and the air damper 215 (215-1 to 215-n) correspond to the supply side valve 204 and the air damper 205, and the recovery side sub tank 218 corresponds to the supply side sub tank 208. ing. The atmosphere communication path 238 and the atmosphere communication valve 240 can be equivalent to the atmosphere communication path 239 and the atmosphere communication valve 241, respectively, and the recovery side sub tank 218 is buffered via the drain flow path 229 and the drain valve 231. The structure communicating with the tank 201B is also common. The pressure sensor 216 can be equivalent to the pressure sensor 206.

  The drain valves 230 and 231, the first bypass passage valve 272, and the second bypass passage valve 273 are latch-type electromagnetic valves, and the supply side valve 204, the recovery side valve 214, and the atmosphere communication valve 240 are applied. , 241 is a normally closed electromagnetic valve.

  The collection-side sub tank 218 communicates with the buffer tank 201B via the collection-side pump 220, the filter 286, and the one-way valve 287. When the collection-side pump 220 is operated, the ink in the head 100 is collected into the collection-side manifold 213, It can be circulated to the buffer tank 201 </ b> B via the circulation channel 212, the collection side sub tank 218, the collection side pump 220, and the one-way valve 283.

  A tube pump that can switch between forward and reverse rotation is also applied to the recovery side pump 220. That is, the supply flow path 202 communicating with the buffer tank 201B has a structure branched on the output side of the deaeration module 276, and the branched flow path is connected to the recovery side pump via the one-way valve 281 and the filter 286. 220. By switching between the forward and reverse rotations of the recovery side pump 220, the amount of ink circulated through the circulation channel 212 can be adjusted, and the pressure in the circulation channel 212 is adjusted.

  Between the supply side pump 210 and the supply side sub tank 208 in the supply flow path 202 and between the recovery side sub tank 218 and the recovery side pump 220 in the circulation flow path 212 are branched, and a safety valve is provided in the branched flow path. 285 and 288 are provided and communicated with the main tank 201A and the buffer tank 201B. When the safety valves 285 and 288 are operated, the ink in the supply channel 202 and the ink in the circulation channel 212 are collected into the main tank 201A.

  As described in FIG. 5, the ink temperature adjuster 278 adjusts the temperature of the ink that passes through the supply flow path 202 and is supplied to the head 100. Since the head 100 shown in this example has good ejection characteristics when the temperature of the ink is within a predetermined range (for example, 20 ° C. or higher and 35 ° C. or lower), the ink supplied to the head 100 is within the predetermined temperature range. The temperature adjustment process is performed so that

  In general, the viscosity of ink used in an ink jet recording apparatus is temperature-dependent, and the viscosity decreases as the temperature increases, and the viscosity increases as the temperature decreases. Further, the ejection characteristics of the head change depending on the viscosity. Since the ejection characteristics of the head affect the quality of the recorded image, the ink temperature is appropriately controlled and the viscosity of the ink is maintained within a predetermined range, so that the predetermined ejection characteristics are maintained and have a predetermined quality. A recorded image can be obtained.

  Further, by periodically supplying the ink whose temperature is adjusted by circulating the ink in the head 100, it is possible to suppress the temperature change of the ink in the head 100 and the occurrence of the temperature distribution. The viscosity of the ink becomes stable.

  Specific examples of the ink temperature adjuster 278 include a cooling device that cools ink having a temperature higher than a predetermined temperature range, and a heating device that performs heat treatment on ink having a temperature lower than the predetermined temperature range. That is, for the temperature adjustment in this example, the ink having a temperature lower than the lower limit value of the predetermined temperature range is subjected to a heating process (or a process for stopping the cooling process), or the upper limit of the predetermined temperature range. A cooling process (or a process of stopping the heating process) is included for ink having a temperature exceeding the value.

[Explanation of condensation prevention treatment method]
Next, a dew condensation prevention treatment method applied to the ink jet recording apparatus 10 shown in this example will be described. In the ink jet recording apparatus 10 shown in this example, the temperature of the ink supplied to the head 100 is managed in order to ensure good ejection characteristics of the head 100. Then, the supply flow path 202 and the circulation flow path 212 through which the temperature-adjusted ink passes become substantially the same as the ink temperature. Further, the periphery of the head 100 is cooled by a cooling device so that the ambient temperature of the head 100 does not exceed a predetermined temperature.

If equipment external (outdoor air) temperature and humidity is higher than the internal device, when being opened cover of the device is outside air high temperature and high humidity enters, the head 100 and the supply passage 202, and the outside air in the circulation flow path 212 There is a risk of condensation on the touched part. In order to prevent such condensation, the following condensation prevention measures are executed.

(First embodiment)
Next, the dew condensation prevention processing method according to the first embodiment of the present invention will be described. FIG. 7 is an excerpt of a part of the dew point temperature table that is referred to when the dew condensation prevention measure shown in this example is executed. First, the outside air temperature and the outside air humidity of the device are detected by the detecting device 90 (the temperature sensor 90A and the humidity sensor 90B shown in FIG. 5), and the detected outside air temperature and the outside air humidity are referred to with reference to the dew point table shown in FIG. The corresponding dew point temperature is determined.

  Here, the “dew point temperature” can be obtained by obtaining a water vapor pressure from the air temperature and relative humidity and obtaining a temperature at which the water vapor pressure is a saturated water vapor pressure. When the relative humidity is 100%, the current temperature is the dew point temperature as it is. The dew point temperature thus obtained is tabulated in association with the outside air temperature (° C.) and the outside air humidity (RH%) as shown in FIG.

  When the dew point temperature is obtained, the dew point temperature is equal to or higher than the dew condensation prevention measure operating temperature of the ink temperature regulator 278 (see FIG. 6) (the temperature at which the dew prevention measure is operated so that the ink temperature range is equal to or higher than the dew point temperature). In this case, the ink temperature adjuster 278 is stopped (the cooling process is stopped) so that the ink temperature follows the environmental temperature. As a result, the temperature of the ink rises, and the temperature of the head 100, the supply flow path 202, and the circulation flow path 212 also rises corresponding to the temperature of the ink, and the difference from the outside air temperature becomes small, resulting in condensation of the head 100 and the like. Is prevented.

  FIG. 8 is a flowchart showing a control flow of the dew condensation prevention processing method shown in this example. The control flow is repeatedly executed at regular intervals. First, in step S10, the outside temperature (outside temperature) and outside humidity (outside air humidity) are measured, and the dew point temperature is determined from the measured outside temperature and outside humidity with reference to the dew point table shown in FIG. Calculated (step S12), the process proceeds to step S14.

  In step S14, the dew point temperature is compared with the dew condensation prevention measure release temperature of the ink temperature adjuster 278 (see FIG. 6). The dew condensation prevention measure canceling temperature is a reference temperature when the ink temperature adjuster 278 is restarted after being stopped, and is set in the ink temperature adjuster 278 in advance. From the viewpoint of preventing hunting (a phenomenon in which the temperature adjustment control is continuously switched on and off in a short cycle), it is preferable that (condensation prevention measure operating temperature)> (condensation prevention measure release temperature).

  In step S14, when the dew point temperature is equal to or higher than the dew condensation prevention measure release temperature (Yes determination), the dew point temperature and the dew prevention measure operation temperature are compared (step S16 in FIG. 8). In step S16, if the dew point temperature is equal to or higher than the dew condensation prevention measure operating temperature, the temperature adjustment control by the ink temperature adjuster 278 is stopped (step S18), and abnormality detection relating to temperature is turned off (step S20).

  On the other hand, if the dew point temperature is lower than the dew condensation prevention measure release temperature in step S14 (No determination), the process proceeds to step S22, and if the temperature adjustment control (processing) is being executed (No determination in step S22), the temperature adjustment is performed. Control continues (step S24). On the other hand, if the temperature adjustment control is stopped (Yes determination in step S22), the temperature adjustment control is resumed (step S26), and on the other hand, abnormality detection related to temperature is turned on (step S28). In step S16, when the dew point temperature is lower than the dew condensation prevention measure operating temperature (No determination), the previous state is maintained.

  For example, considering the case where the temperature is adjusted in the temperature range of 22 ° C. to 24 ° C., the minimum temperature during execution of the temperature adjustment control is 22 ° C. In other words, the operation temperature of the dew prevention measure of the ink temperature adjuster 278 may be set to 22 ° C. or lower, and the operation temperature of the dew prevention measure is set to 22 ° C. Also, the dew condensation prevention measure release temperature is set to 21 ° C. to prevent hunting.

  If the dew point temperature obtained from the outside air temperature and the outside air humidity is a value within the thick frame line in FIG. 9, the temperature adjustment by the ink temperature adjuster 278 is stopped because there is a risk of condensation. On the other hand, if the dew point temperature obtained from the outside air temperature and the outside air humidity is a value within the thick frame line in FIG. 10, the temperature adjustment by the ink temperature adjuster 278 is resumed because there is no possibility of condensation. When the dew point temperature is 21.8 ° C (outside air temperature 32.0 ° C, outside air humidity 55.0RH%) and 21.4 ° C (outside air temperature 30.0 ° C, outside air humidity 60.0RH%) The previous state is maintained.

FIG. 11 is an explanatory diagram schematically illustrating the above-described dew condensation prevention measure. In FIG. 11, the temperature region illustrated with hatching is the temperature adjustment range of the ink temperature adjuster 278. Condensation prevention operation temperature is set at 22 ° C. which is the lower limit of the temperature adjustment range, condensation prevention release temperature is set at 21 ° C. less than the lower limit value of the temperature regulating Ceyhan circumference.

  According to the dew condensation prevention processing method configured as described above, the outside air temperature and the outside air humidity are detected, and the dew point temperature is calculated based on the outside air temperature and the outside air humidity. Since the ink temperature adjustment is stopped, dew condensation on the head 100, the supply flow path 202, and the circulation flow path 212 is prevented by making the ink temperature follow the ambient temperature.

  In addition, since the ink temperature adjuster 278 is stopped to make the ink temperature follow the environmental temperature, it contributes to low power consumption. Furthermore, by setting the operating temperature of the dew prevention measure to a temperature below the lower limit value of the temperature adjustment range of the ink temperature adjuster 278 and setting the dew prevention measure release temperature at which the temperature adjustment is resumed below the dew condensation prevention measure operating temperature, Is prevented.

(Second Embodiment)
Next, the dew condensation prevention processing method according to the second embodiment of the present invention will be described. In addition, in 2nd Embodiment demonstrated below, the same code | symbol is attached | subjected to the part which is the same as that of 1st Embodiment demonstrated previously, or is the same, and the description is abbreviate | omitted and it is mainly different from 1st Embodiment. The points to be described will be described.

  In the second embodiment, the temperature adjustment target value is set using the “temperature fluctuation range”, and the ink temperature adjustment is controlled based on the temperature adjustment target value. FIG. 12 is a flowchart showing the flow of the dew condensation prevention processing method according to the second embodiment. In the flowchart shown in FIG. 8, steps S18, S22, and S26 in the flowchart shown in FIG. 8 are changed to steps S18 ', S22', and S26 ', respectively. That is, instead of stopping the ink temperature adjustment control in step S18 shown in FIG. 8, the ink temperature adjustment target value is set in step S18 ′ shown in FIG. 12, and the ink temperature adjustment is performed based on the temperature adjustment target value. Is done. In step S22 ', it is confirmed whether or not the temperature adjustment target temperature has been changed. In step S26', the temperature adjustment target temperature is returned to the original set temperature.

  The temperature adjustment target value is set to a value equal to or larger than the value obtained by (dew point temperature) + (temperature fluctuation range / 2). Here, the “temperature fluctuation range” is a value obtained by subtracting the minimum temperature from the maximum temperature of the temperature adjustment range of the ink temperature adjuster 278. For example, when the temperature adjustment range is 22 ° C. to 24 ° C., 24−22 = 2 (° C.).

  With reference to the dew point temperature table shown in FIG. 9, the temperature adjustment target value when the dew point temperature obtained from the outside air temperature and the outside air humidity is 24 ° C. is set to 25 (= 24 + (2/2)) ° C. or more. . For example, when the temperature adjustment target value is set to 25 ° C., the operation of the ink temperature adjuster 278 is controlled so that the ink temperature becomes 25 ° C. On the other hand, when the dew point temperature calculated from the outside air temperature and the outside air humidity is 21 ° C. or less, there is no possibility of condensation, and therefore normal temperature adjustment is resumed.

  According to the second embodiment, it takes only a short time to prevent condensation, which is an effective countermeasure against condensation. A cooling device that cools the ink and a heating device that heats the ink may be provided, and the temperature adjustment and the dew condensation prevention measure may be executed while switching between the cooling device and the heating device.

  In this example, the dew condensation prevention processing method in the ink supply unit 200 provided in the inkjet recording apparatus 10 has been described. However, the ink supply unit 200 illustrated in FIG. 6 can be configured as a single ink supply device. . That is, the present invention can be applied to an ink jet head (liquid ejection head) and a liquid supply apparatus that supplies liquid to the liquid ejection apparatus.

  Examples of the liquid to which the present invention is applicable include a liquid that can be ejected by an ink jet method, such as a resin liquid containing resin particles in a solvent and a treatment liquid that agglomerates ink.

(First application example)
Next, application examples of the above-described first and second embodiments will be described. In the dew condensation prevention processing method according to the first application example, the drive waveform is changed to ensure the ejection reliability of the head 100 when the ink set temperature is changed. When the ink temperature adjustment range is set higher than the standard setting range, the amplitude of the drive waveform (the maximum voltage of the drive voltage) is lowered. For example, when the ink temperature increases by 5 ° C., the drive waveform is changed so as to decrease the amplitude by 10%.

  The drive waveform is changed by the head drive unit 148 shown in FIG. For example, a configuration in which a drive waveform for each setting of the set temperature is created and stored in advance and the drive waveform is read in accordance with the setting can be mentioned. Also, by dividing the drive voltage corresponding to the setting, changing the gain of the drive waveform corresponding to the setting, and changing the image data (serial data) corresponding to the setting, It is possible to change the amplitude of the drive waveform of the drive voltage.

  By changing the driving waveform, even when the set temperature is changed, preferable image recording is performed without affecting the image quality (discharge characteristics) such as the disturbance of the recorded image.

(Second application example)
Next, a second application example will be described. In the dew condensation prevention processing method shown in this example, when the ink set temperature is changed, the differential pressure value related to the circulation amount setting of the head 100 during ink circulation is changed. When the ink set temperature is set higher than the standard value, the differential pressure value is set smaller than the standard value. For example, when the ink temperature adjustment range is set to be 5 ° C. higher than the standard setting range, the differential pressure value is set to be 15% smaller than the standard setting value.

  The change of the differential pressure value is realized by changing the rotation speed (discharge amount or suction amount) of the supply side pump 210 and the recovery side pump 220 shown in FIG. For example, the relationship between the temperature control temperature and the differential pressure value is stored in advance, and the rotation speeds of the supply side pump 210 and the recovery side pump 220 may be adjusted in accordance with the setting.

  Even when the ink set temperature is changed by changing the differential pressure value, the ink circulation amount becomes constant, and the quality of the recorded image is ensured.

(Third application example)
Next, a third application example will be described. In the dew condensation prevention treatment method shown in this example, for example, when using an ink that can provide good ejection characteristics within a viscosity of 5 cP or less, the ink is set to a temperature lower than the above viscosity. An upper limit is provided. If the ink shown in this example is used in a viscosity state lower than the predetermined viscosity range, the predetermined ejection characteristics cannot be obtained, the quality of the recorded image is lowered, and the head 100 may be deteriorated. For example, when a predetermined ejection characteristic cannot be obtained when the ink temperature exceeds 35 ° C., the ink temperature is adjusted so as not to exceed the temperature upper limit value.

[Example of application to other device configurations]
In this example, an ink jet recording apparatus has been described as an example of a liquid ejection apparatus. However, the scope of the present invention is not limited to the use of so-called graphic printing such as photographic printing and poster printing. Also included are industrial-use devices that can form patterns that can be grasped as images, such as wiring drawing devices and fine structure forming devices.

<Appendix>
As can be understood from the description of the embodiment described in detail above, the present specification includes disclosure of various technical ideas including the invention described below.

  (Invention 1): Supply channel for supplying a liquid to a liquid supply target, temperature adjusting means for adjusting the temperature of the liquid supplied to the liquid supply target to a predetermined temperature adjustment range, and the liquid supply target And a detecting means for detecting a temperature and humidity around the supply flow path, a dew point temperature deriving means for deriving a dew point temperature based on the detected temperature and humidity, and temperature adjustment by the temperature adjusting means. Setting means for setting the temperature, anti-condensation measure for preventing dew condensation by setting the liquid temperature to be equal to or higher than the derived dew point temperature, and the dew dew point temperature and the dew condensation preventing measure operating temperature for operating the dew condensation preventive measure And a dew condensation prevention processing means for executing the dew condensation prevention measure when the dew point temperature is equal to or higher than the dew condensation prevention measure operating temperature.

  According to the present invention, the dew point temperature is derived based on the temperature and humidity around the device, while the dew prevention measure operating temperature for executing the dew condensation prevention measure is set, and the dew prevention measure is implemented based on the derived dew point temperature. Since it is determined whether or not it is executed, the temperature and humidity range in which the apparatus can be operated becomes wider than when the temperature and humidity are independently determined and the anti-condensation measure is executed. At the same time, a preferable dew condensation prevention measure adapted to the temperature and humidity conditions around the apparatus is executed.

  As a specific example of the liquid supply target in the present invention, a liquid discharge head such as an ink jet head that discharges liquid by an ink jet method can be given.

  Other temperatures (control parameters) set by the setting means include the upper limit temperature, lower limit temperature, adjustment target temperature of the temperature adjustment range, and dew condensation prevention measure release temperature that resumes temperature adjustment when temperature adjustment is stopped. It is done. A mode provided with setting value storage means for storing such setting values is preferable.

  As a specific example of deriving the dew point temperature, there is a mode in which data in a table format with temperature and humidity as parameters are referred to.

  (Invention 2): In the liquid supply apparatus according to Invention 1, the setting means sets a temperature equal to or lower than a lower limit value of a temperature adjustment range of the temperature adjustment means as the operation temperature for preventing condensation, and the condensation prevention processing means. Is characterized in that the temperature adjustment means is controlled to stop the temperature adjustment process as the dew condensation prevention measure.

  According to this aspect, the power consumption can be reduced by stopping the operation of the temperature adjusting means as the condensation prevention process.

  (Invention 3): In the liquid supply apparatus according to Invention 1 or 2, the setting means uses a value obtained by subtracting a lower limit value from an upper limit value of a temperature adjustment range by the temperature adjustment means as a temperature fluctuation range, and the dew point temperature and Using the temperature fluctuation range, the target temperature satisfying the following formula (target temperature) = (dew point temperature) + (temperature fluctuation width / 2) is set as a target temperature for temperature adjustment by the temperature adjusting means. And

  According to this aspect, the effect of the condensation prevention process can be obtained in a shorter time.

  (Invention 4): In the liquid supply device according to any one of Inventions 1 to 3, it is determined whether or not there is a failure based on the temperature of the liquid supplied to the liquid supply target, while the dew condensation prevention process It is characterized in that there is provided judgment means configured to be switchable so as not to judge whether or not there is a failure during execution of the dew condensation prevention processing by the means.

  According to this aspect, erroneous determination of abnormality due to a change in the temperature adjustment setting is prevented.

  (Invention 5): In the liquid supply device according to any one of Inventions 1 to 4, the detection means detects the temperature and humidity of the outside air.

  In this aspect, “outside air” includes both outside air of the liquid supply apparatus and outside air to be supplied with liquid.

  (Invention 6): a liquid discharge head that discharges liquid, and a liquid supply device that supplies liquid to the liquid discharge head, wherein the liquid supply device includes a supply channel that supplies liquid to the liquid discharge head; Temperature adjusting means for adjusting the temperature of the liquid supplied to the liquid discharge head within a predetermined temperature adjustment range, and detection means for detecting the temperature and humidity around the liquid discharge head and the supply flow path. A dew point temperature deriving means for deriving a dew point temperature based on the detected temperature and humidity, a setting means for setting a temperature relating to temperature adjustment by the temperature adjusting means, and a liquid temperature equal to or higher than the derived dew point temperature. The dew point temperature is compared with the dew point temperature that has been derived, and the dew point temperature at which the dew point temperature is activated. For more temperature, the liquid ejection apparatus is characterized in that and a dew condensation preventing processing means for executing the condensation prevention.

  According to the present invention, by providing temperature adjusting means for adjusting temperature such as heating and cooling in addition to the liquid discharge head, a dew condensation prevention effect can be expected for the entire liquid supply area.

  The liquid ejection apparatus in the present invention includes an inkjet recording apparatus including an inkjet head that ejects liquid by an inkjet method.

  (Invention 7): In the liquid ejection device according to Invention 6, the setting means sets a temperature not more than a lower limit value of a temperature adjustment range of the temperature adjustment means as the operation temperature for preventing condensation, and the condensation prevention processing means. Is characterized in that the temperature adjustment means is controlled to stop the temperature adjustment process as the dew condensation prevention measure.

  (Invention 8): In the liquid ejection apparatus according to Invention 6 or 7, the setting means uses a value obtained by subtracting a lower limit value from an upper limit value of a temperature adjustment range by the temperature adjustment means as a temperature fluctuation range, and the dew point temperature and Using the temperature fluctuation range, the target temperature satisfying the following formula (target temperature) = (dew point temperature) + (temperature fluctuation width / 2) is set as a target temperature for temperature adjustment by the temperature adjusting means. And

  (Invention 9): In the liquid ejecting apparatus according to any one of claims 6 to 8, while determining whether or not there is a failure based on the temperature of the liquid supplied to the liquid supplied to the liquid ejecting head. Further, it is characterized in that there is provided judgment means configured to be switchable so as not to judge whether or not there is a failure during execution of the condensation prevention processing by the condensation prevention processing means.

  (Invention 10): In the liquid ejection device according to any one of Inventions 6 to 9, the detection means detects the temperature and humidity of the outside air.

  (Invention 11): In the liquid ejecting apparatus according to any one of Inventions 6 to 10, the liquid ejecting head includes a pressurizing unit that pressurizes the liquid to be ejected, and a driving voltage having a predetermined waveform in the pressurizing unit. Drive voltage supply means for supplying, wherein the drive voltage supply means changes the waveform of the drive voltage supplied to the pressurizing means when the condensation prevention processing is performed by the condensation prevention means. And

  According to this aspect, even if the temperature of the ink changes due to the dew condensation prevention process, the discharge performance of the liquid discharge head is maintained and the image quality is not affected.

  In such an aspect, it is preferable that the relationship between the waveform of the drive voltage (drive waveform) and the control parameter of the dew condensation prevention process be stored as table format data.

  (Invention 12): In the liquid ejection apparatus according to any one of Inventions 6 to 11, the operation of the supply-side pressure applying unit that applies pressure to the liquid in the supply flow path and the operation of the supply-side pressure applying unit are controlled. Pressure control means, and the pressure control means applies the supply side pressure so as to change the pressure applied to the liquid in the supply flow path when the condensation prevention processing by the condensation prevention means is executed. The means is controlled.

  According to this aspect, the back pressure (internal pressure) of the liquid ejection head during continuous operation is stable, and the ejection characteristics of the liquid ejection head are maintained even during continuous operation.

  In such an aspect, an aspect including a sub-tank having a function of buffering pressure fluctuation in the supply flow path is preferable.

  (Invention 13): In the liquid discharge apparatus according to the invention 12, the circulation flow path for circulating the liquid from the liquid discharge head, the circulation side pressure applying means for applying pressure to the liquid in the circulation flow path, and the supply A liquid storage means that communicates with the flow path and the circulation flow path, stores the liquid supplied to the liquid discharge head, and collects the liquid circulated from the liquid discharge head; Pressure detection means for detecting pressure and pressure in the circulation flow path, and the pressure control means includes the supply side pressure application means and the circulation side pressure application means based on the detection result of the pressure detection means. When the control is performed and the dew condensation prevention process is performed by the dew condensation prevention unit, the supply side pressure applying unit and the circulation are changed so as to change the differential pressure of the liquid discharge head when the liquid is circulated. And controlling the pressure applying means.

  According to this aspect, even when the set temperature of the ink is changed, the ink circulation amount is constant and the good ejection characteristics of the liquid ejection head are maintained.

  In such an aspect, an aspect including a supply side subtank having a function of buffering pressure fluctuations in the supply flow path and a recovery side subtank having a function of buffering pressure fluctuations in the circulation flow path is preferable.

  (Invention 14): In the liquid ejecting apparatus according to any one of Inventions 6 to 13, the dew condensation prevention processing unit sets a temperature upper limit value when performing the dew condensation prevention process.

  According to this aspect, the ejection characteristics of the liquid ejection head are maintained even during the execution of the condensation prevention process.

  (Invention 15): A temperature adjustment step of adjusting the temperature of the liquid supplied to the liquid supply target via the liquid flow path to a predetermined temperature adjustment range, and the liquid supply target and the supply flow path are installed. A detection step for detecting ambient temperature and humidity, a dew point temperature deriving step for deriving a dew point temperature based on the detected temperature and humidity, a temperature setting step for setting a temperature related to temperature adjustment by the temperature adjustment step, Condensation prevention measures for preventing condensation by setting the liquid temperature to be equal to or higher than the derived dew point temperature, and the derived dew point temperature and a predetermined condensation prevention measure operating temperature for executing the condensation prevention measures. In comparison, when the dew point temperature is equal to or higher than the dew condensation prevention measure operating temperature, a dew condensation prevention treatment step of executing the dew condensation prevention measure is included.

  In the present invention, the setting step sets a temperature equal to or lower than the lower limit value of the adjustment range of the temperature adjustment step to the temperature adjustment stop condensation prevention measure operating temperature, and the condensation prevention treatment step is controlled to stop the temperature adjustment treatment. Is preferred.

  Further, the setting step uses a value obtained by subtracting the lower limit value from the upper limit value of the temperature adjustment range in the temperature adjustment step as a temperature fluctuation range, and uses the dew point temperature and the temperature fluctuation range, and the following formula (target temperature) = (dew point) It is also preferable that the target temperature satisfying (temperature) + (temperature fluctuation range / 2) is set as a target temperature for temperature adjustment in the temperature adjustment step.

  Further, it is determined whether or not there is a failure based on the temperature of the liquid supplied to the liquid supply target, while determining whether or not there is a failure during the execution of the condensation prevention measure in the condensation prevention processing step. A mode including a determination step configured to be switchable so as not to be switched is preferable.

  In addition, the present specification includes disclosure of various technical ideas including the invention described below.

  A supply flow path for supplying a liquid to a liquid supply target; temperature adjusting means for adjusting a temperature of the liquid supplied to the liquid supply target to a predetermined temperature adjustment range; and the liquid supply target and the supply flow path Detecting means for detecting the temperature and humidity in the vicinity of the installation, dew point temperature deriving means for deriving the dew point temperature based on the detected temperature and humidity, and setting for setting the temperature related to temperature adjustment by the temperature adjusting means And a temperature control stop temperature for stopping the temperature adjustment process set by the setting means, and if the dew point temperature is equal to or higher than the temperature control stop temperature, a dew condensation prevention process A liquid supply apparatus comprising: a dew condensation prevention processing unit that executes

  In the above invention, the setting means sets a temperature that is equal to or lower than a lower limit value of a temperature adjustment range of the temperature adjustment means to the temperature adjustment stop temperature, and the dew condensation prevention processing means stops the temperature adjustment process so that the temperature adjustment process is stopped. A liquid supply apparatus that controls the adjusting means.

  Further, in the above invention, the setting means uses a value obtained by subtracting a lower limit value from an upper limit value of a temperature adjustment range by the temperature adjustment means as a temperature fluctuation range, and uses the dew point temperature and the temperature fluctuation range as follows: The liquid supply apparatus, wherein the target temperature satisfying (target temperature) = (dew point temperature) + (temperature fluctuation range / 2) is set as a target temperature for temperature adjustment by the temperature adjusting means.

  In the above invention, it is determined whether or not there is a failure based on the temperature of the liquid supplied to the liquid supply target, and whether or not there is a failure during the execution of the condensation prevention processing by the condensation prevention processing means. A liquid supply apparatus comprising: a determination unit configured to be switchable so as not to perform the determination.

  In the above invention, the detection means detects the temperature and humidity of the outside air.

  A liquid discharge head that discharges the liquid; and a liquid supply device that supplies the liquid to the liquid discharge head, wherein the liquid supply device supplies a liquid to the liquid discharge head, and the liquid discharge head Temperature adjusting means for adjusting the temperature of the liquid supplied to a predetermined temperature adjustment range, detecting means for detecting the temperature and humidity around the liquid discharge head and the supply flow path, and the detected Dew point temperature deriving means for deriving dew point temperature based on temperature and humidity, setting means for setting temperature related to temperature adjustment by the temperature adjusting means, and temperature adjustment processing set by the derived dew point temperature and the setting means And a dew condensation prevention process means for performing a dew condensation prevention process when the dew point temperature is equal to or higher than the temperature regulation stop temperature. A liquid discharge apparatus characterized.

  In the above invention, the setting means sets a temperature not more than a lower limit value of a temperature adjustment range of the temperature adjustment means to the temperature adjustment stop temperature, and the dew condensation prevention processing means stops the temperature adjustment process. A liquid discharge apparatus that controls the temperature adjusting means.

  Further, in the above invention, the setting means uses a value obtained by subtracting a lower limit value from an upper limit value of a temperature adjustment range by the temperature adjustment means as a temperature fluctuation range, and uses the dew point temperature and the temperature fluctuation range as follows: A liquid ejection apparatus, wherein the target temperature satisfying (target temperature) = (dew point temperature) + (temperature fluctuation range / 2) is set as a target temperature for temperature adjustment by the temperature adjusting means.

  In the above invention, it is determined whether or not there is a failure based on the temperature of the liquid supplied to the liquid ejection head, and whether or not there is a failure during the execution of the condensation prevention processing by the condensation prevention processing means. A liquid ejection apparatus comprising: a determination unit configured to be switchable so as not to perform the determination.

  In the above invention, the detecting means detects the temperature and humidity of the outside air.

  In the above invention, the liquid discharge head includes a pressurizing unit that pressurizes the liquid to be ejected, and a drive voltage supply unit that supplies a driving voltage having a predetermined waveform to the pressurizing unit, The liquid ejecting apparatus according to claim 1, wherein the supply unit changes a waveform of a driving voltage supplied to the pressurizing unit when the dew condensation preventing process is performed by the dew condensation preventing unit.

  Further, in the above invention, the apparatus includes a supply-side pressure applying unit that applies pressure to the liquid in the supply flow path, and a pressure control unit that controls an operation of the supply-side pressure applying unit. The liquid discharging apparatus according to claim 1, wherein when the dew condensation preventing process is performed by the dew condensation preventing unit, the supply side pressure applying unit is controlled to change a pressure applied to the liquid in the supply flow path.

  In the above invention, the circulation flow path for circulating the liquid from the liquid discharge head, the circulation side pressure applying means for applying pressure to the liquid in the circulation flow path, and the communication with the supply flow path and the circulation flow path And a liquid storage means for storing the liquid supplied to the liquid discharge head and collecting the liquid circulated from the liquid discharge head, and the pressure in the supply flow path and the pressure in the circulation flow path. The pressure control means for controlling the supply-side pressure application means and the circulation-side pressure application means based on the detection result of the pressure detection means, and the dew condensation prevention means. When the dew condensation prevention process is executed, the supply-side pressure application unit and the circulation-side pressure application unit are controlled so as to change the internal pressure of the liquid discharge head when the liquid is circulated. Liquid discharge apparatus characterized by and.

  In the above invention, the dew condensation prevention processing unit sets a temperature upper limit value when the dew condensation prevention process is executed.

  A temperature adjustment step of adjusting the temperature of the liquid supplied to the liquid supply target via the liquid flow path to a predetermined temperature adjustment range; and the temperature and humidity around the liquid supply target and the supply flow path are installed A dew point temperature deriving step for deriving a dew point temperature based on the detected temperature and humidity, a stop temperature setting step for setting a temperature related to temperature adjustment by the temperature adjusting step, and the derived Condensation prevention processing step of comparing the dew point temperature with the temperature adjustment stop temperature for stopping the temperature adjustment processing set in the setting step, and executing the condensation prevention processing when the dew point temperature is equal to or higher than the temperature adjustment stop temperature And a method for preventing condensation.

  DESCRIPTION OF SYMBOLS 10 ... Inkjet recording device, 48M, 48K, 48C, 48Y, 100 ... Head, 90, 90A, 90B ... Detection device, 142 ... System control unit, 148 ... Head drive unit, 168 ... Ink supply control unit, 180 ... Parameter storage Part, 210, 220 ... pump, 278 ... ink temperature regulator (heat exchanger)

Claims (16)

A supply flow path for supplying liquid to a liquid supply target;
Temperature adjusting means for adjusting the temperature of the liquid supplied to the liquid supply target to a predetermined temperature adjustment range;
Detection means for detecting the temperature and humidity around the liquid supply target and the supply flow path;
Dew point temperature deriving means for deriving a dew point temperature based on the detected temperature and humidity;
Condensation prevention processing means for controlling the temperature adjusting means to execute condensation prevention measures for preventing condensation by setting the temperature of the liquid to be equal to or higher than the derived dew point temperature;
Setting means for setting a temperature applied to the dew condensation prevention measure;
With
In the setting means, the temperature adjustment process of the temperature adjustment means is a cooling process, and at the lower limit of the temperature adjustment range, a temperature adjustment stop set in advance as a temperature when the temperature adjustment process of the temperature adjustment means is stopped Set the temperature as the anti-condensation measure operating temperature, which is the temperature at which the anti-condensation measure starts.
The dew condensation prevention processing means compares the derived dew point temperature with the set dew condensation prevention measure operating temperature, and executes the dew condensation prevention measure when the dew point temperature is equal to or higher than the dew condensation prevention measure operating temperature. A liquid supply apparatus. The liquid supply apparatus according to claim 1,
The setting means sets the temperature below the lower limit value of the temperature adjustment range of the temperature adjustment means as the dew condensation prevention measure operating temperature,
The dew condensation prevention processing unit controls the temperature adjustment unit to stop the temperature adjustment processing as the dew condensation prevention measure. The liquid supply apparatus according to claim 1 or 2,
The setting means sets a condensation prevention measure release temperature that is a temperature equal to or lower than the condensation prevention measure operation temperature and is a temperature at which the execution of the condensation prevention measure is released, and the derived dew point temperature is the set condensation. A value obtained by subtracting the lower limit value from the upper limit value of the temperature adjustment range by the temperature adjustment means when the dew point temperature is not less than the prevention measure release temperature and the derived dew point temperature is not less than the set condensation prevention measure operation temperature. Using the dew point temperature and the temperature fluctuation range as the temperature fluctuation range, the following equation (target temperature) = (dew point temperature) + (temperature fluctuation range / 2)
The liquid supply apparatus according to claim 1, wherein the target temperature that satisfies the above condition is set to a target temperature for temperature adjustment by the temperature adjusting means. The liquid supply apparatus according to any one of claims 1 to 3,
While it is determined whether or not there is a failure based on the temperature of the liquid supplied to the liquid supply target, it is not determined whether or not there is a failure during the execution of the dew condensation prevention measure by the dew condensation prevention processing means. A liquid supply apparatus comprising: a determination unit configured to be switchable as described above. The liquid supply apparatus according to any one of claims 1 to 4,
The liquid supply apparatus according to claim 1, wherein the detection means detects the temperature and humidity of the outside air. The liquid supply apparatus according to any one of claims 1 to 5,
The setting means sets a temperature upper limit value of the liquid when the dew condensation prevention measure is executed;
The liquid supply apparatus, wherein the temperature adjusting means adjusts the temperature of the liquid to a temperature lower than the temperature upper limit value. A liquid discharge head for discharging liquid;
A liquid supply device for supplying liquid to the liquid discharge head;
With
The liquid supply device includes a supply flow path for supplying a liquid to the liquid discharge head,
Temperature adjusting means for adjusting the temperature of the liquid supplied to the liquid discharge head to a predetermined temperature adjustment range;
Detecting means for detecting temperature and humidity around the liquid discharge head and the supply flow path;
Dew point temperature deriving means for deriving a dew point temperature based on the detected temperature and humidity;
Condensation prevention processing means for controlling the temperature adjusting means to execute condensation prevention measures for preventing condensation by setting the temperature of the liquid to be equal to or higher than the derived dew point temperature;
Setting means for setting a temperature applied to the dew condensation prevention measure;
With
In the setting means, the temperature adjustment process of the temperature adjustment means is a cooling process, and at the lower limit of the temperature adjustment range, a temperature adjustment stop set in advance as a temperature when the temperature adjustment process of the temperature adjustment means is stopped Set the temperature as the anti-condensation measure operating temperature, which is the temperature at which the anti-condensation measure starts.
The dew condensation prevention processing means compares the derived dew point temperature with the set dew condensation prevention measure operating temperature, and executes the dew condensation prevention measure when the dew point temperature is equal to or higher than the dew condensation prevention measure operating temperature. A liquid discharge apparatus characterized by: The liquid ejection device according to claim 7, wherein
The setting means sets the temperature below the lower limit value of the temperature adjustment range of the temperature adjustment means as the dew condensation prevention measure operating temperature,
The dew condensation prevention processing unit controls the temperature adjustment unit to stop the temperature adjustment processing as the dew condensation prevention measure. The liquid ejection apparatus according to claim 7 or 8,
The setting means sets a condensation prevention measure release temperature that is a temperature equal to or lower than the condensation prevention measure operation temperature and is a temperature at which the execution of the condensation prevention measure is released, and the derived dew point temperature is the set condensation. A value obtained by subtracting the lower limit value from the upper limit value of the temperature adjustment range by the temperature adjustment means when the dew point temperature is not less than the prevention measure release temperature and the derived dew point temperature is not less than the set condensation prevention measure operation temperature. Using the dew point temperature and the temperature fluctuation range as the temperature fluctuation range, the following equation (target temperature) = (dew point temperature) + (temperature fluctuation range / 2)
The liquid discharge apparatus according to claim 1, wherein the target temperature that satisfies the above condition is set to a target temperature for temperature adjustment by the temperature adjusting means. The liquid ejection apparatus according to any one of claims 7 to 9,
While it is determined whether or not there is a failure based on the temperature of the liquid supplied to the liquid discharge head, it is not determined whether or not there is a failure during the execution of the condensation prevention measure by the condensation prevention processing means. A liquid ejecting apparatus comprising: a determination unit configured to be switchable to each other. The liquid ejection device according to any one of claims 7 to 10,
The liquid ejecting apparatus according to claim 1, wherein the detecting means detects the temperature and humidity of outside air. The liquid ejection apparatus according to any one of claims 7 to 11,
The liquid discharge head includes a pressurizing unit that pressurizes the liquid to be discharged;
Drive voltage supply means for supplying a drive voltage having a predetermined waveform to the pressurizing means;
With
The liquid discharge apparatus according to claim 1, wherein the drive voltage supply means changes the waveform of the drive voltage supplied to the pressurizing means when the dew condensation prevention measure is executed by the dew condensation prevention processing means. The liquid ejection device according to any one of claims 7 to 12,
Supply-side pressure applying means for applying pressure to the liquid in the supply flow path;
Pressure control means for controlling the operation of the supply side pressure applying means;
With
The pressure control unit controls the supply-side pressure applying unit to change the pressure applied to the liquid in the supply flow path when the dew condensation prevention measure is executed by the dew condensation prevention processing unit. A liquid ejection device. The liquid ejection apparatus according to claim 13, wherein
A circulation channel for circulating liquid from the liquid discharge head;
A circulation side pressure applying means for applying pressure to the liquid in the circulation flow path;
A liquid storage unit that communicates with the supply flow path and the circulation flow path, stores liquid supplied to the liquid discharge head, and collects liquid circulated from the liquid discharge head; and Pressure detection means for detecting the internal pressure and the pressure in the circulation channel;
With
The pressure control means controls the supply-side pressure application means and the circulation-side pressure application means based on the detection result of the pressure detection means, and when the condensation prevention measure by the condensation prevention processing means is executed, A liquid ejection apparatus that controls the supply-side pressure application means and the circulation-side pressure application means so as to change a differential pressure of the liquid ejection head when circulating the liquid. The liquid ejection apparatus according to any one of claims 7 to 14,
The setting means sets a temperature upper limit value of the liquid when the dew condensation prevention measure is executed;
The temperature adjusting means adjusts the temperature of the liquid to a temperature lower than the temperature upper limit value. A temperature adjustment step of adjusting the temperature of the liquid supplied to the liquid supply target via the supply flow path to a predetermined temperature adjustment range;
A detection step of detecting a temperature and humidity around the liquid supply target and the supply flow path;
A dew point temperature deriving step for deriving a dew point temperature based on the detected temperature and humidity;
A dew condensation prevention treatment step for controlling a temperature adjustment means used in the temperature adjustment step to prevent dew condensation by making the temperature of the liquid equal to or higher than the derived dew point temperature; and
A temperature setting step for setting a temperature applied to the dew condensation prevention measure;
Including
In the temperature setting process, the temperature adjustment process of the temperature adjustment process is a cooling process, and at the lower limit of the temperature adjustment range, a temperature adjustment preset as a temperature when the temperature adjustment process of the temperature adjustment process is stopped is preset. Set the stop temperature as the anti-condensation measure operating temperature that is the temperature at which the anti-condensation measure starts.
The dew condensation prevention processing step compares the derived dew point temperature with the set dew condensation prevention measure operation temperature, and executes the dew condensation prevention measure when the dew point temperature is equal to or higher than the dew condensation prevention measure operation temperature. The dew condensation prevention processing method characterized by performing.

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