JP2010058338A - Liquid droplet ejection device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To achieve a wiping head wiping a nozzle forming face without damaging the nozzle forming face by ink or a foreign matter. <P>SOLUTION: The wiping head 30 for wiping a nozzle forming face of an inkjet head is provided with: a wiping blade 1 for wiping the nozzle forming face; a deterrent plate 3 that is disposed to face the wiping blade 1 and has one end away from the nozzle forming face; and a supply plate 2 that is disposed between the wiping blade 1 and the deterrent plate 3 in such a manner that one end thereof is away from the nozzle forming face more than the deterrent plate 3 and is adapted to supply cleaning liquid to a nozzle forming face side. By supplying the cleaning liquid from the supply plate 2, a wiping operation is carried out under the condition that the wiping blade 1 is wet. The wiping operation is carried out, therefore, without damaging the nozzle forming face by solidified ink or a foreign matter. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a wiping head and a wiping device for wiping a nozzle forming surface of an inkjet head.

  2. Description of the Related Art Conventionally, a droplet discharge device has been widely used because it can easily and vividly perform color printing and has a low running cost. In recent years, research and development for manufacturing a liquid crystal television, an organic EL, and the like using a droplet discharge device have been conducted, and interest in using the droplet discharge device as a manufacturing device is increasing.

  When using a droplet discharge device as a manufacturing device, it is particularly important to accurately discharge droplets to an inkjet head. In order to increase this accuracy, it is necessary to prevent the dye or pigment in the droplets from adhering to the nozzle surface of the ink jet head or the adhesion of foreign matter.

  As a means for recovering the nozzle formation surface of the ink jet head to which droplets have adhered, there are a method of forcibly discharging droplets by suction and pressurization, a method of cleaning the nozzle formation surface, a method of excessively discharging ink from the nozzles Can be mentioned. Among these methods, the method of cleaning the nozzle formation surface generally uses a method of wiping the nozzle formation surface with a plate-like wipe blade made of an elastic body.

  For example, Patent Document 1 discloses a wipe blade made of an elastic material and having a hollow portion that holds a cleaning liquid therein. In Patent Document 1, when wiping, the wipe blade that contacts the nozzle forming surface is pressed and deformed, and thereby, the cleaning liquid in the void is discharged from the wipe blade and adheres to the nozzle forming surface. Since the wiping is performed while the nozzle forming surface is wetted by the cleaning liquid, the efficiency of removing dirt on the nozzle forming surface is improved.

  Further, when the wipe blade is used for a long period of time, dirt such as ink and dust attached to the wipe blade by one wiping is accumulated every time the wiping is repeated. If left as it is, the accumulated ink is dried and solidified, and at the time of wiping, the wiping blade itself is worn to cause wiping residue or damage the nozzle forming surface. As a result, the ink jet head may not be able to perform a correct ejection operation. Therefore, in order to maintain the initial discharge accuracy by the ink jet head for a long time, it is necessary to always keep the wipe blade in a clean state.

For example, Patent Document 2 discloses a technique for providing a wipe blade cleaning mechanism in order to keep the wipe blade in a clean state. In Patent Document 2, a cleaning tank storing a cleaning liquid is provided in the cleaning mechanism, and a contact portion of a wipe blade that is in contact with a nozzle forming surface is held in a wet state by being immersed in the cleaning tank. .
JP 2005-7635 A (published January 13, 2005) JP 2007-203660 A (published August 16, 2007)

  In the wipe blade described in Patent Document 1, it is necessary to increase the thickness of the wipe blade to such an extent that a hollow portion can be provided inside. For this reason, with the wipe blade described in Patent Document 1, it is difficult to appropriately set the contact length with respect to the nozzle formation surface of the inkjet head. Since the setting of the contact length is related to the contact pressure acting on the head nozzle forming surface, if the contact pressure cannot be set appropriately and the contact pressure becomes large, the wipe blade Damages the head nozzle formation surface.

  Further, the wipe blade described in the cited document 1 accumulates dirt such as ink and dust attached to the wipe blade. According to this, at the time of wiping, the dried and solidified ink or the like may damage the nozzle forming surface.

  On the other hand, in the cleaning mechanism described in the cited document 2, after wiping, a small amount of ink is mixed in the cleaning liquid in the cleaning tank. For this reason, if the cleaning mechanism described in the cited document 2 is continuously operated for a long period of time, the amount of mixed ink in the cleaning tank increases, and the cleaning liquid itself in the cleaning tank becomes dirty. In order to prevent ink from being mixed in the cleaning tank, the cleaning liquid stored in the cleaning tank must be discharged and supplied after each wiping. However, when such measures are taken, the amount of cleaning liquid required increases significantly.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to enable wiping in a wet state without damaging the nozzle forming surface of the inkjet head, and more desirably, wiping with less cleaning liquid. An object of the present invention is to provide a wiping head and a wiping device capable of keeping the blade wet.

  In order to solve the above problems, the wiping head according to the present invention is a wiping head for wiping the nozzle forming surface of an inkjet head, and a wipe blade for wiping the nozzle forming surface, facing the wipe blade, and One end of the plate is disposed away from the nozzle forming surface, and one end is disposed between the wipe blade and the plate away from the nozzle forming surface than the plate, and the cleaning liquid is disposed on the nozzle forming surface side. And a supply unit for supplying the power.

  According to the above configuration, the supply unit is disposed between the wipe blade and the plate, and the wipe blade and the plate have a height on the nozzle forming surface side when viewed from the supply unit. Since the plate plays a role of suppressing the overflow of the cleaning liquid on the side where the plate is disposed, the cleaning liquid supplied from the supply unit spreads between the wipe blade and the plate.

  When the wiping head performs the wiping operation, if the supply unit supplies the cleaning liquid, the cleaning liquid spreads between the wipe blade and the nozzle forming surface with which the wipe blade contacts. Further, when the wiping head performs a wiping operation in a direction in which the side on which the plate is formed is directed forward, the contact portion of the wipe blade that is in contact with the nozzle formation surface wipes the nozzle formation surface in a wet state ( Wet wiping). By wet wiping, the nozzle forming surface can be efficiently cleaned, and the nozzle forming surface can be restored to a clean state even after using ink that has high viscosity and is easy to dry.

  When the wiping head performs the wiping operation, the amount of the cleaning liquid supplied from the supply unit is limited so that the cleaning liquid does not touch the nozzle forming surface, so that the nozzle forming surface is wiped in a dry state (dry wiping). You can also Therefore, if the cleaning liquid remains on the nozzle forming surface after wet wiping, the cleaning liquid may be removed by dry wiping.

  In the wiping head according to the present invention, when the width in the longitudinal direction of the wipe blade is a1 and the width in the longitudinal direction of the plate is a2 on the side facing the nozzle forming surface, a1 ≦ a2. It is preferable.

  Furthermore, in the wiping head according to the present invention, it is preferable that a1 ≦ a3 ≦ a2 when the width in the longitudinal direction of the supply unit is a3 on the side facing the nozzle formation surface.

  According to the above configuration, when the width of the plate is equal to or larger than the width of the wipe blade, the cleaning liquid spreading between the wipe blade and the plate flows from the break of the plate in the middle of the width of the wipe blade. Can be prevented. That is, the cleaning liquid can be distributed to both sides of the contact portion of the wipe blade.

  Furthermore, when the width of the supply unit is equal to or larger than the width of the wipe blade, the cleaning liquid can sufficiently spread between the wipe blade and the plate. On the other hand, when the width of the supply unit is equal to or less than the width of the plate, it is possible to prevent the cleaning liquid from flowing excessively from the wiping head.

  The wiping head according to the present invention can be used in a wiping device.

  In order to solve the above-described problem, the wiping device according to the present invention is in contact with the cleaning liquid supplied to the supply unit when the wiping head is in the wiping standby position, and the wiping blade is wiped away from the site. It is characterized by having a moisturizing portion arranged in close proximity.

  Ink tends to adhere to a portion (abutting portion) to be wiped by the wipe blade, and if the ink is dried, it is fixed to the wipe blade.

  According to the above configuration, when the wiping head is in the wiping standby position, the moisturizing unit is close to the contact portion of the wipe blade. At this time, the moisturizing unit comes into contact with the cleaning liquid supplied from the supply unit. As a result, the cleaning liquid is held between the moisturizing part and the contact part of the wipe blade by the surface tension. Therefore, when the wiping head is at the wiping standby position, the moisturizing unit can keep the contact portion of the wipe blade in the moisturizing state.

  Further, after wiping, foreign substances such as ink adhering to the wipe blade can be removed by continuously supplying the cleaning liquid from the supply unit at the wiping standby position.

  In the wiping device according to the present invention, it is preferable that the width of the moisturizing portion is larger than the width of the wipe blade in the longitudinal direction of the surface of the moisturizing portion facing the wipe blade.

  According to the above configuration, the moisturizing part can keep the contact part of the wipe blade sufficiently moisturized to both ends.

  Moreover, in the wiping apparatus according to the present invention, it is preferable that the moisturizing part has liquid repellency.

  According to the above configuration, even if the ink adhering to the wipe blade is transferred to the moisturizing unit, when the wiping head is at the wiping standby position, the cleaning liquid is supplied from the supply unit and the moisturizing unit is allowed to flow with the cleaning liquid. Thus, the ink transferred to the moisture retaining portion can be easily removed.

  Further, in the wiping apparatus according to the present invention, a supply unit that supplies the cleaning liquid to the supply unit, a supply control unit that controls the supply unit, and a discharge unit that discharges the cleaning liquid supplied to the supply unit. It is preferable to provide.

  According to the above configuration, a necessary amount of cleaning liquid can be supplied when necessary. For example, it is possible to supply a cleaning liquid necessary for wiping in a wet state at the time of wiping, or to supply a cleaning liquid necessary for holding the contact portion of the wipe blade in a wet state at the time of wiping standby. Further, by discharging the used cleaning liquid that has flowed out of the wiping head, it is possible to prevent the cleaning liquid from accumulating under the wiping head.

  In the wiping apparatus according to the present invention, it is preferable that the wiping device includes a moving unit that moves the wiping head and a movement control unit that controls the moving unit.

  According to the above configuration, the wiping operation of the wiping head and the positioning of the wiping head at the wiping standby position can be repeatedly performed.

  According to the wiping device of the present invention, in the wiping head for wiping the nozzle forming surface of the inkjet head, the wipe blade for wiping the nozzle forming surface, the wipe blade facing the wipe blade, and one end from the nozzle forming surface. A plate disposed at a distance, and a supply unit that is disposed between the wipe blade and the plate at one end away from the nozzle forming surface than the plate, and that supplies cleaning liquid to the nozzle forming surface side. Therefore, it is possible to perform wiping in a wet state without damaging the nozzle forming surface of the ink jet head, and it is possible to effectively remove attached ink and the like.

  An embodiment of the present invention will be described below with reference to FIGS.

  First, a schematic configuration of the wiping head 30 included in the wiping device 40 will be described with reference to FIGS. 2 and 3. 2A is a top view showing the wiping head 30 in the present embodiment, FIG. 2B is a side view (sectional view) thereof, and FIG. 2C is a front view thereof. FIG. 3 is a perspective view showing the flow of the cleaning liquid in the wiping head 30, and the arrows in the figure indicate the direction in which the cleaning liquid flows.

  The wiping head 30 is a member that performs a wiping operation in the wiping device 40. In this specification, the side of the wiping head 30 that faces the head nozzle formation surface is the upper side, and the front side in the wiping direction is the front side.

  As shown in FIGS. 2A to 2C, the wiping head 30 includes a wipe blade 1, a supply plate 2, a suppression plate 3, an absorber 4, and a blade holder 5. A thin supply plate 2 having a supply port 2 a is adjacent to the wipe blade 1. A deterrence plate 3 that suppresses the flow of the cleaning liquid is adjacent to the front of the supply plate 2. The wipe blade 1, the supply plate 2, and the suppression plate 3 are positioned on the blade holder 5 by pins or contact surfaces. An absorber 4 is disposed below the wipe blade 1 and the suppression plate 3. Further, the blade holder 5 is formed with a supply flow path 5b connected to the supply port 2a and a discharge flow path 5a connected to the absorber 4. The supply channel 5 b is connected to the cleaning liquid inlet 6.

  The wipe blade 1 is preferably formed of a material made of an elastic body. Examples of such materials include rubber and elastomer. In particular, the wipe blade 1 is preferably formed of a material having chemical resistance such as perfluoro rubber (Perflo (registered trademark: Daikin Industries)). Further, the wipe blade 1 is not bonded to the supply plate 2. For this reason, at the time of wiping, only the wiping blade 1 bends and performs wiping without contacting the supply plate 2.

  The supply plate 2 is a plate whose height from the blade holder 5 is lower than that of the wipe blade 1 and the suppression plate 3. The supply plate 2 is not particularly limited, but may be formed of resin or metal. On the upper surface of the supply plate 2, a supply port 2a for supplying the cleaning liquid is formed. As shown in FIG. 2A, the supply port 2a may have a shape that is long in the longitudinal direction of the upper surface of the supply plate 2, or may be a plurality of small holes. According to these shapes, when the amount of the cleaning liquid to be supplied is small, the cleaning liquid is prevented from being ejected from the supply port 2a.

  The suppression plate 3 is a plate having a height from the blade holder 5 lower than that of the wipe blade 1 and a height from the blade holder 5 higher than that of the supply plate 2. By being higher than the supply plate 2, it is possible to prevent the cleaning liquid from flowing toward the suppression plate 3 side. Further, like the wipe blade 1, the suppression plate 3 is preferably formed of a material made of an elastic body. This is because when the adjustment of the wiping head in the height direction is performed, the suppression plate 3 may come into contact with the nozzle forming surface and be damaged by an erroneous operation. If the suppression plate 3 is an elastic body, even if the suppression plate 3 and the nozzle formation surface come into contact with each other, the nozzle formation surface is not damaged.

  The absorber 4 only needs to have a configuration capable of uniformly discharging the used cleaning liquid, and the wipe holder 5 has a strength for positioning and holding the height positions of the wipe blade 1, the supply plate 2, and the suppression plate 3. If there is. The restraining plate 3 is positioned so as to be positioned away from the nozzle surface when the wipe blade 1 comes into contact with the nozzle surface. Further, the absorber 4 has a structure sealed with an O-ring or the like so that the cleaning liquid discharge flow path 5a and the cleaning liquid supply flow path 5b are not mixed. The structure has a feature that the wipe blade 1, the supply plate 2, and the suppression plate 3 can be easily replaced during maintenance.

  When the pump for supplying the cleaning liquid is operated with respect to the wiping head 30 having the above configuration, the cleaning liquid flows into the supply flow path 5b from the cleaning liquid inlet 6 as shown in FIG. Is supplied to the outside from the center of the supply port 2a on the upper surface. The supplied cleaning liquid flows to both ends of the supply plate 2 through the space between the wipe blade 1 and the suppression plate 3. Thereafter, the cleaning liquid overflowing from both ends of the supply plate 2 is absorbed by the absorber 4.

  Next, a wiping operation and a wiping standby state for the wiping head 30 will be described with reference to FIGS. 1 and 4. FIGS. 1A and 1B are side (cross-sectional) views showing the wiping head 30 during the wiping operation. FIG. 4 is a side (cross-sectional) view showing the wiping head 30 in a wiping standby state.

  The wiping head 30 in the present embodiment can perform two types of wiping when wiping the nozzle forming surface. That is, wet wiping and dry wiping.

  First, wet wiping will be described. As shown in FIG. 1A, during the wiping operation of the wiping head 30, the wipe blade 1 contacts the nozzle forming surface 9b while being bent by the contact pressure with the nozzle forming surface 9b. A portion of the wipe blade 1 that contacts the nozzle forming surface 9b is referred to as a contact portion (edge portion) of the wipe blade 1. The cleaning liquid is supplied from the supply plate 2 before the wipe blade 1 reaches the head nozzle 9a. The supplied cleaning liquid spreads between the contact portion of the wipe blade 1 and the nozzle forming surface 9b, and the contact portion of the wipe blade 1 becomes wet. Accordingly, the wipe blade 1 wipes the nozzle forming surface 9b in a wet state in the direction of the hollow arrow in FIG.

  By such wet wiping, it is possible to effectively remove ink or the like adhering to the nozzle forming surface 9b. Further, even if solidified ink or foreign matter adheres to the nozzle forming surface 9b, wiping can be performed without damaging the nozzle 9a.

  On the other hand, as shown in FIG. 1B, dry wiping is the same as wet wiping except that wiping is performed without supplying a cleaning liquid. For example, after the wet wiping is performed, when the cleaning liquid remains on the nozzle forming surface 9b, the cleaning liquid can be removed by performing dry wiping. Further, if the solidified ink or foreign matter is not attached to the nozzle forming surface 9b, dry wiping may be performed without performing wet wiping.

  After a series of wiping operations, the wiping head 30 moves to the wiping standby position. As shown in FIG. 4, a moisturizing unit 8 is provided at the wiping standby position. The wipe blade 1 is positioned close to the moisturizing unit 8. The detailed configuration of the moisturizing unit 8 will be described later.

  When the cleaning liquid is supplied from the supply plate 2, the cleaning liquid is held between the wipe blade 1 and the moisturizing unit 8 by the surface tension, and the contact portion of the wipe blade 1 is kept wet by the cleaning liquid. According to this, even if foreign matter or ink remains on the contact portion of the wipe blade 1, it is possible to prevent them from sticking.

  After the wiping head 30 moves to the wiping standby position, the cleaning liquid supply pump is continuously driven to sufficiently supply the cleaning liquid in order to remove the wiped ink and foreign matters from the contact portion of the wipe blade 1. Is preferred. Since the cleaning liquid can spread to the contact portion of the wipe blade 1 at the wiping standby position, the contact portion of the wipe blade 1 can be cleaned by sufficiently supplying the cleaning liquid. After this cleaning, it is preferable to wait until the next wiping operation while keeping the contact portion of the wipe blade 1 in a wet state.

  If the cleaning liquid is likely to evaporate, the supply pump connected to the cleaning liquid supply flow path 5b may be driven at any time in accordance with the evaporation speed of the cleaning liquid during standby for wiping to supply only the necessary amount of cleaning liquid. .

  Next, the moving means of the wiping unit 14 including a plurality of wiping heads 30 will be described with reference to FIGS. 5 and 6 are perspective views schematically showing the moving means of the wiping unit 14. FIG. 5 shows a wiping standby time, and FIG. 6 shows a wiping time. Although the ink jet head is not a constituent element of the wiping device 40, the outer edge of the ink jet head 9 is shown by broken lines in FIGS.

  As shown in FIGS. 5 and 6, the wiping unit 14 includes a plurality of blade holders 5 that support the wipe blade 1. In the moving means of the wiping unit 14, the wiping unit 14 is connected to the drive shaft 11 and moves along the guide rail 12 as the motor 10 rotates.

  In the moving means of the wiping unit 14, an origin sensor and a limit sensor (not shown) are attached to the side of the guide rail 12. During the origin return operation, the origin sensor detects the origin position of the wiping unit 14 and sends a pulse signal to the motor 10 to operate the wiping unit 14. Further, the current position of the wiping unit 14 can be detected by reading this pulse signal.

  On the other hand, two limit sensors are attached to the upper limit side and the lower limit side in the moving direction. Even if an erroneous control signal is sent and the wiping unit 14 malfunctions, the motor 10 can be stopped when either of the limit sensors detects the malfunction of the wiping unit 14.

  At the wiping standby position, the position of the wipe blade 1 adjacent to the moisturizing unit 8 is adjusted, and the position is set on the control board that sends a pulse signal. Thus, after wiping, the wiping unit 14 automatically moves to the set position and stands by.

  The moisturizing portion 8a for the wiping unit 14 is fixed by the side plate 13 so as to be close to the plurality of wipe blades 1 of the wiping unit 14, respectively. At this time, the moisturizing portion 8a may be provided with a groove between the positions where the wipe blades 1 are arranged. For example, when different types of ink are used in a plurality of inkjet heads, this groove can prevent ink from being mixed.

  Next, supply means for supplying the cleaning liquid to the wiping unit 14 and discharge means for discharging the used cleaning liquid will be described with reference to FIG. FIG. 7 is a schematic diagram schematically showing supply means for supplying the cleaning liquid to the wiping unit 14 and discharge means for discharging the used cleaning liquid.

  In the supply means for supplying the cleaning liquid, as shown in FIG. 7, the cleaning liquid tank 17 and each of the plurality of wipe blades 1 are connected via a supply pipe 19 having a supply pump 15 disposed in the middle. The cleaning liquid tank 17 is a tank that stores the cleaning liquid. When the supply pump 15 is driven, the cleaning liquid 7 stored in the cleaning liquid tank 17 flows through the supply pipe 19 and is supplied from the supply port 2 a of the supply plate 2.

  When the remaining amount of the cleaning liquid 7 in the cleaning liquid tank 17 becomes small, the empty sensor 21 detects and prompts the user to replenish the cleaning liquid 7. Examples of the empty sensor 21 that can be used here include those with specifications based on optical, electrostatic capacitance, and weight detection methods.

  On the other hand, in the discharge means for discharging the used cleaning liquid, the common discharge flow path in the wiping unit 14 is connected to the waste liquid tank 18 via the waste liquid pipe 20 in which the waste liquid pump 16 is disposed in the middle. The used cleaning liquid that overflows when wiping with the wipe blade 1 or when the cleaning liquid is used more than necessary is driven by the waste liquid pump 16 from the common discharge flow path in the wiping unit 14 via the waste liquid piping 20. And stored in the waste liquid tank 18.

  When the waste liquid tank 18 is filled with the stored used cleaning liquid, a full sensor (warning) 22 is first detected to alert the user to replace the waste liquid tank 18. Thereafter, the user only needs to replace the waste liquid tank 18 after the ink jet apparatus is stopped. If the waste liquid tank 18 is filled with waste liquid during operation of the ink jet apparatus, the full sensor (error) 23 detects and transmits an error signal to the control board, thereby stopping the ink jet apparatus. .

  The supply means for supplying the cleaning liquid may include a plurality of cleaning liquid tanks 17 as shown in FIG. FIG. 8 is a configuration diagram schematically showing supply means and waste liquid means when a plurality of cleaning liquid tanks 17 are provided. By providing a plurality of cleaning liquid tanks 17, a plurality of types of cleaning liquids can be used in one wiping device 40. In FIG. 8, the cleaning liquid tanks 17 a to 17 c and the supply pump 15 are independently connected to each wiping head 1, and the cleaning liquids 7 a to 7 c are supplied to the supply port 2 a of each wiping head 1, respectively. Is done.

  As the discharge means for discharging the used cleaning liquid, a common flow path may be used as long as the flow path such as the pipe diameter of the waste liquid pipe 20 is sufficiently large, or a plurality of waste liquid pumps and independent flow paths are provided. May be.

  Next, the size relationship among the wiping blade 1, the supply plate 2, and the suppression plate 3 in the wiping head 30 will be described below with reference to FIGS. Hereinafter, in order to describe the size relationship, the wiping heads 30 in which the sizes of the wipe blade 1, the supply plate 2, and the suppression plate 3 are changed are compared. FIGS. 9A to 9E are top views of the wiping head 30 for schematically showing the size relationship among the wipe blade 1, the supply plate 2, and the suppression plate 3. FIG. 10 is a table showing the determination results for the wet state of each of the wiping heads 30 in FIGS. FIG. 11 is a front view of the wiping head 30.

  In the determination result shown in FIG. 10, the size relationship is preferable for the case where the cleaning liquid spreads to both ends 1a of the wipe blade 1 shown in FIG. 11 during both the wiping operation and the wiping standby. Circled.

  According to the determination result shown in FIG. 10, in order for the cleaning liquid 7 to spread to both end portions 1a of the wipe blade 1, the wipe blade 1 as shown in FIGS. 9 (a), 9 (b), and 9 (c) is supplied. The size relationship between the plate 2 and the suppression plate 3 is preferable. In the case of FIG. 9D, the cleaning liquid flows forward from the end portion of the suppression plate 3 and does not spread to both end portions 1 a of the wipe blade 1. In the case of FIG. 9E, the cleaning liquid spreads to a certain extent due to the wettability of the cleaning liquid itself, but may not spread to both end portions 1a of the wipe blade 1 in some cases. It is difficult to make it wet.

  Therefore, in the longitudinal direction of the upper surface of the wipe blade 1 shown in FIG. 9, when the width of the wipe blade 1 is a1, the width of the supply plate 2 is a2, and the width of the suppression plate 3 is a3, a1 ≧ a2 ≧ a2 Preferably there is.

  Next, the moisturizing unit 8 included in the wiping device 40 will be described below with reference to FIGS.

  FIG. 12 shows the state of the cleaning liquid when the cleaning liquid is supplied from the supply plate 2 when the moisturizing unit 8 is not present at the wiping standby position. FIG. 12A is a side (cross-sectional) view showing the wiping head 30, and FIG. 12B is an enlarged view of the vicinity of the contact portion of the wiping blade 1 in FIG. 12A.

  As shown in FIGS. 12A and 12B, if the moisturizing unit 8 does not exist at the wiping standby position, the cleaning liquid supplied from the supply plate 2 often forms a downwardly convex shape. The shape of the cleaning liquid varies depending on the surface tension of the cleaning liquid, the wettability between the cleaning liquid, the wipe blade 1 and the suppression plate 3, and the distance between the wipe blade 1 and the suppression plate 3. When the cleaning liquid has a downwardly convex shape as shown in FIG. 12, the cleaning liquid does not reach the part indicated by the arrow in FIG. 12B, that is, the contact portion of the wipe blade 1. For this reason, if the moisturizing portion 8 does not exist at the wiping standby position, it is difficult to completely remove foreign matter or ink even if the foreign matter or ink adheres to the contact portion of the wipe blade 1.

  On the other hand, if the moisturizing unit 8 is used as shown in FIG. 13, the cleaning liquid spreads over the entire contact portion of the wipe blade 1. FIG. 13A is a side (cross-sectional) view showing the wiping head 30 and the moisturizing portion 8, and FIG. 13B is an enlarged view of the vicinity of the contact portion of the wiping blade 1 in FIG. It is an enlarged view.

  The moisturizing unit 8 may be disposed so as not to contact the wipe blade 1 with respect to the wiping standby position of the wipe blade 1 and to contact the cleaning liquid supplied from the supply plate 2. That is, the moisturizing unit 8 only needs to be able to hold the cleaning liquid by surface tension between the contact portion of the wipe blade 1. In this state, if a sufficient amount of cleaning liquid is further supplied, even if foreign matter or ink is attached to the wipe blade 1, these can be removed. Further, the moisturizing unit 8 can keep the contact portion of the wipe blade 1 in a wet state by maintaining a state in which the cleaning liquid is held with the contact portion of the wipe blade 1.

  In addition, it is preferable that there is a mechanism that can finely adjust the height and tilt of the wiping head 30 so that the position of the wipe blade 1 with respect to the moisturizing unit 8 is in an optimal position. For example, when cleaning liquids having different surface tensions are used, the moisturizing unit 8 holds the cleaning liquid in an optimum state between the contact portion of the wipe blade 1 by performing fine adjustment according to the surface tension of the cleaning liquid. can do.

  Regarding the shape of the moisturizing portion 8, the width of the moisturizing portion 8 is preferably larger than the width of the wipe blade 1 in the longitudinal direction of the upper surface of the wipe blade 1. As a result, the cleaning liquid can be sufficiently retained up to both end portions 1a of the wipe blade 1 in FIG. Further, it is preferable that the corner portion facing the wipe blade 1 in the moisturizing portion 8 is subjected to R processing. As a result, even when the wipe blade 1 contacts the moisturizing portion 8 when the wipe blade 1 moves from the standby position to the head nozzle formation surface, the contact portion of the wipe blade 1 can be prevented from being damaged.

  The shape of the moisturizing unit 8 is not limited to that shown in FIGS. The position of the wipe blade 1 is important to adjust the distance 24 between the wipe blade 1 and the moisturizing portion 8 with respect to the moisturizing portion 8 so that the cleaning liquid can be held by the surface tension between the contact portion of the wipe blade 1 and the wipe blade 1. It is. However, as shown in FIG. 13, when only one surface of the moisturizing unit 8 is close to the wipe blade 1, it is relatively difficult to adjust the distance 24. Therefore, the moisturizing part 8 may have a shape like the moisturizing part 8 ′ shown in FIG. 14. The moisturizing portion 8 ′ also has a surface close to the wipe blade 1 on the upper side of the wipe blade 1. According to this configuration, since the contact portion of the wipe blade 1 is completely covered with the cleaning liquid, the distance 24 can be adjusted so that the cleaning liquid can be held by surface tension between the wiper blade 1 and the contact portion of the wipe blade 1. It becomes easy.

  Further, the shape of the moisturizing portion 8 is not limited to a quadrangular cross section as shown in FIGS. 13A and 13B, and the cross section may be a triangle or a circle.

  Of the surface of the moisturizing portion 8, it is preferable that at least a portion close to the wiping head 30 has liquid repellency. Note that all of the surface may be volatile. Such a volatility can be realized by devising a material constituting the moisturizing unit 8. For example, the entire moisturizing portion 8 may be formed of a material having liquid repellency, or the surface of the moisturizing portion 8 may be coated with a material having liquid repellency. In the case where the surface of the moisturizing portion 8 is coated, the inner material is not limited. Examples of the material having liquid repellency include materials such as fluorine resin and stainless steel. Further, in the case of coating the surface of the moisturizing portion 8, a film forming process may be performed using polyimide, DLC (diamond-like carbon), or the like. Since the surface of the moisturizing unit 8 has liquid repellency, even if foreign matter or ink attached to the wipe blade 1 is transferred to the moisturizing unit 8, the cleaning liquid is continuously flowed from the cleaning unit 2 at the wiping standby position. The foreign matter and ink transferred to the moisturizing unit 8 can be easily removed.

  Next, preferable dimensions in the wiping head 30 will be described. Considering that the height difference between the wipe blade 1 and the restraining plate 3 is a contact length of a general wipe blade of 0.5 to 1.5 mm, (contact length) + (0.1 to 0.5 mm) ) Is preferable.

  The gap 24 between the supply plate 8 and the wipe blade 1 is preferably about 0.1 to 1.0 mm. The space 25 between the moisturizing unit 8 and the suppression plate 3 may be in contact with each other.

  The thickness of the supply plate 2 (the distance between the wipe blade 1 and the suppression plate 3) is preferably about 1.5 to 3.0 mm. If there is no problem in processing or molding, the supply plate The thickness of 2 is preferably smaller even within the above range.

(Other embodiments)
The wiping head according to the present invention can also be configured as follows.

  In a wiping mechanism that wipes and cleans ink and foreign matter adhering to the surface of an inkjet head nozzle that ejects droplets onto a medium with a wiper blade, the wipe blade that contacts the head nozzle surface, and the wipe blade wiping A member that is provided with a supply port for supplying cleaning liquid forward and a plate that suppresses outflow of cleaning liquid and is low by at least the contact length of the wipe blade, and is close to the contact portion of the wipe blade when positioned at the wiping standby position And a wiping head characterized by comprising:

  The present invention is not limited to the above-described embodiments, and various modifications can be made within the scope shown in the claims. That is, embodiments obtained by combining technical means appropriately modified within the scope of the claims are also included in the technical scope of the present invention.

  Using the example of the present invention and the conventional example, the amount of the cleaning liquid necessary to keep the contact portion of the wipe blade 1 in a wet state was compared.

  In the example, a wiping head 30 as shown in FIGS. 15A and 15B was used. FIG. 15A is a perspective view showing the wiping head of the embodiment, and FIG. 15B is a side view (cross section) thereof. In addition, the wiper blade 1, the supply plate 2, and the suppression plate 3 in the wiping head 30 were each of the size relationships shown in FIGS. 9 (a), (b), and (c).

  On the other hand, in the conventional example, a cleaning mechanism for the wipe blade 101 using a cleaning tank as shown in FIG. 16 was used. FIG. 16 (a) is a perspective view schematically showing a conventional cleaning mechanism, FIG. 16 (b) is a schematic view showing its side, and FIG. 16 (c) is a schematic view showing its front. . The cleaning mechanism of the conventional example has a configuration in which the cleaning liquid is stored in the cleaning tank 102, and the wipe blade 101 rotates around the rotation shaft 103 so that the contact portion of the wipe blade 101 is immersed in the cleaning liquid. The wiping blade 101 is submerged during wiping standby, and at the time of wiping, wiping is performed after the wiping blade 101 is raised by rotating 180 degrees. In addition, the thing of the circular-arc-shaped cross section which is a shape with a small amount of washing | cleaning liquid stored especially in the washing tank was used for the washing tank 102 of a prior art example.

  For the wipe blade 1 in the example and the wipe blade 101 in the conventional example, those having the same size in width a, height b, and thickness were used. Further, the height difference h (blade submerged portion height) between the wipe blade 1 and the supply plate 2 in the embodiment and the height h (blade submerged portion height) at which the wipe blade 1 in the conventional example is submerged in the cleaning liquid. It was made to become the same value.

  As a factor that influences the amount of cleaning liquid used, there is a supply plate thickness t in the embodiment, and gaps (clearances) x and y between the wipe blade 101 and the cleaning tank 102 in the conventional example. Therefore, the supply plate thickness t in the example is set to 1.5 mm, 2 mm, and 3 mm from the preferable range of 1.5 to 3.0 mm, respectively, while the gap between the cleaning tank and the blade in the conventional example is set. x and y were respectively set to 2 mm.

  Measurement of the amount of cleaning liquid used in the examples and comparative examples is necessary for a single wipe blade 1 from the wiping standby state until the contact portion of the wipe blade 1 is held with the cleaning liquid after completion of one wiping operation. The amount of the cleaning solution was measured.

  Specifically, in the examples, the amount necessary for initial filling and the amount necessary for holding with the cleaning liquid were measured. With respect to the supply of the cleaning liquid, when the wipe blade 1 is in the wiping standby position, the supply pump is driven to hold the cleaning liquid, and wet wiping is performed without driving the supply pump from this state. The pump was driven for the time necessary to remove the water.

  On the other hand, in the conventional example, as shown in FIG. 16B, the amount of the cleaning liquid filling the inside of the cleaning tank 102 was measured.

  As the cleaning liquid, a solvent having a surface tension value smaller than that of water was used.

  Table 1 shows the results of Examples and Conventional Examples.

  In Table 1, examples having the size relationships of FIGS. 9A, 9B, and 9C are shown as a, b, and c, respectively.

  From the results shown in Table 1, it was found that even in the examples in any of cases a, b, and c, the amount of the cleaning liquid used was smaller than that in the conventional example. In particular, in the case of Example a, the amount of the cleaning liquid used could be reduced by 67% compared to the conventional example.

  Further, the thickness t of the supply plate in the embodiment is set to 2 mm constant, while the gaps x and y between the cleaning tank 102 and the wipe blade 101 in the conventional example are set to three types of 1 mm, 2 mm, and 5 mm, respectively. The results when set are shown in Table 2.

  In Table 2, examples having the size relationships shown in FIGS. 9A, 9B, and 9C are shown as a, b, and c, respectively.

  From the results shown in Table 2, it was found that in this case as well, the amount of the cleaning liquid used was smaller than that of the conventional example in any of the examples of a, b, and c. In particular, in the case of Example c, the amount of the cleaning liquid used could be reduced by 86% compared to the conventional example.

  In Table 2, when the clearance between the cleaning tank 2 of the conventional example and the wipe blade 101 is set to 1 mm, the cleaning liquid reduction rate is not large compared to other cases, but (total cleaning liquid usage) = (single Considering the amount of cleaning liquid used by the wipe blade) × (number of wipe blades) × (number of wiping operations), it can be easily understood that even if the reduction rate is small, a great effect can be obtained if it is used as an ink jet apparatus.

  The wiping head and wiping device according to the present invention can be suitably used for, for example, a droplet discharge device including a nozzle forming surface of an inkjet head.

(A) (b) is side surface sectional drawing which shows the wiping head which concerns on one Embodiment of this invention at the time of wiping. (A) is the top view of the wiping head concerning one Embodiment of this invention, (b) is the (side) sectional drawing, (c) is the front view. It is a perspective view which shows the flow of the washing | cleaning liquid in a wiping head. It is sectional drawing which shows the wiping standby state of a wiping head. 1 is a perspective view of a wiping device according to an embodiment of the present invention. 1 is a perspective view of a wiping device according to an embodiment of the present invention. It is a schematic diagram explaining the supply means and discharge means of the cleaning liquid in the wiping device. It is a schematic diagram explaining the supply means and discharge means of the cleaning liquid in the wiping device. It is a top view of the wiping head which shows the size relationship of a wipe blade, a supply board, and a suppression board. 10 is a table showing a comparison result of the wiping head in FIG. 9. FIG. 10 is a front view of the wiping head in FIG. 9. (A) is sectional drawing which shows a wiping head, (b) is sectional drawing to which the contact part vicinity of the wipe blade was expanded. (A) is sectional drawing which shows a wiping head and a moisture retention part, (b) is sectional drawing to which the contact part vicinity of the wipe blade was expanded. It is sectional drawing which shows the other form of a moisturizing part. (A) is a perspective view which shows the wiping head of an Example, (b) is the side sectional drawing. (A) is a perspective view which shows the wipe blade and washing tank of a prior art example, (b) is the side view, (c) is the front view.

Explanation of symbols

1 Wipe blade
2 Supply plate
3 deterrent plate
8 Moisturizing part
10 Motor
11 Drive shaft
12 Guide rail
13 Side plate
14 Wiping unit 15 Supply pump
16 Waste liquid pump
17 Cleaning liquid tank
18 Waste liquid tank
19 Supply piping
20 Waste liquid piping
30 Wiping head 40 Wiping device

Claims (9)

In the wiping head for wiping the nozzle forming surface of the inkjet head,
A wipe blade for wiping the nozzle forming surface;
A plate facing the wipe blade and having one end disposed away from the nozzle forming surface;
One end is arranged between the wipe blade and the plate away from the nozzle forming surface than the plate, and a supply unit that supplies the cleaning liquid to the nozzle forming surface side,
Wiping head characterized by comprising. On the side facing the nozzle forming surface,
2. The wiping head according to claim 1, wherein when the width in the longitudinal direction of the wipe blade is a1 and the width in the longitudinal direction of the plate is a2, a1 ≦ a2. On the side facing the nozzle forming surface,
3. The wiping head according to claim 2, wherein a <b> 1 ≦ a <b> 3 ≦ a <b> 2, where a <b> 3 is a width in the longitudinal direction of the supply unit.   A wiping apparatus comprising the wiping head according to any one of claims 1 to 3.   When the wiping head is at a wiping standby position, the wiping head is provided with a moisturizing unit that is in contact with the cleaning liquid supplied to the supply unit and is disposed in the vicinity of a portion to be wiped by the wipe blade. Item 5. The wiping device according to Item 4. In the longitudinal direction of the surface of the moisturizing part facing the wipe blade,
6. The wiping apparatus according to claim 5, wherein a width of the moisturizing unit is larger than a width of the wipe blade.   The wiping apparatus according to claim 5 or 6, wherein the moisturizing part has liquid repellency. Supply means for supplying a cleaning liquid to the supply unit;
Supply control means for controlling the supply means;
The wiping apparatus according to any one of claims 4 to 7, further comprising: a discharge unit that discharges the cleaning liquid supplied to the supply unit. Moving means for moving the wiping head;
The wiping apparatus according to claim 4, further comprising a movement control unit that controls the movement unit.