JP2015134448A - Liquid ejection device - Google Patents

Abstract

A liquid ejecting apparatus capable of wiping a nozzle surface while reducing a frictional force between the nozzle surface and a wiping member is provided. A nozzle array including a plurality of nozzles is formed on a nozzle surface, and includes a recording head that ejects liquid from the nozzles, and a wiping unit having a wiping member having liquid retention properties. The first region W of the wiping member 37 wetted by the liquid ejected from the nozzle 22 abuts the nozzle region An including the nozzle row 23 of the nozzle surface 28 and the first wiping member 37. The second area D deviating from the area W of the nozzle is in contact with the non-nozzle area Aa deviating from the nozzle area An of the nozzle surface 28, and the recording head 3 and the wiping unit 11 move relative to each other in the nozzle row direction 23. The first area W wipes the nozzle area An, and the second area D wipes the non-nozzle area Aa. [Selection] Figure 5

Description

  The present invention relates to a liquid ejecting apparatus such as an ink jet recording apparatus, and more particularly to a liquid ejecting apparatus including a liquid ejecting head that has a nozzle row including a plurality of nozzles and ejects liquid from each nozzle.

  The liquid ejecting head is a device that ejects various liquids from nozzles. As this liquid ejecting head, for example, there is an ink jet recording head (hereinafter simply referred to as a recording head) used in an image recording apparatus such as an ink jet printer or an ink jet plotter. Recently, a very small amount of liquid is placed in a predetermined position. It has been applied to various manufacturing equipment by taking advantage of its ability to land accurately. For example, a display manufacturing apparatus for manufacturing a color filter such as a liquid crystal display, an electrode forming apparatus for forming an electrode such as an organic EL (Electro Luminescence) display or FED (surface emitting display), a chip for manufacturing a biochip (biochemical element) It is applied to manufacturing equipment. The recording head for the image recording apparatus ejects liquid ink, and the color material ejecting head for the display manufacturing apparatus ejects solutions of R (Red), G (Green), and B (Blue) color materials. The electrode material ejecting head for the electrode forming apparatus ejects a liquid electrode material, and the bioorganic matter ejecting head for the chip manufacturing apparatus ejects a bioorganic solution.

  The above-described liquid ejecting head causes pressure fluctuation in the liquid in the pressure chamber by driving the pressure generating means, and ejects ink droplets from the nozzles opened on the nozzle surface. Here, when ink droplets are ejected (discharged) from the nozzles of the liquid ejecting head, fine droplets (mist) may scatter and adhere to the nozzle surface. If this mist adheres to the vicinity of the nozzle, it may cause not only ejection failure such as ink flying bend, but also further generation of mist. For this reason, a liquid ejecting apparatus in which a liquid repellent (ink repellent) film is formed on the nozzle surface is known in order to suppress the spread of mist (ink) attached to the nozzle surface. There is also known a liquid ejecting apparatus configured to wipe the nozzle surface periodically in order to wipe mist (ink) adhering to the nozzle surface. As a method for wiping the nozzle surface, in addition to a wiper made of resin or the like, a sheet-like wiping member made of cloth or the like is brought into contact with the nozzle surface, and the liquid ejecting head is moved relative to the wiping member. A method of wiping the nozzle surface is employed.

  By the way, if the wiping of the nozzle surface is repeatedly performed, the liquid repellent film formed on the nozzle surface may be deteriorated due to wear. For this reason, in order to reduce the frictional force between the nozzle surface and the liquid ejecting head as much as possible, the wiping member is relatively moved in the same direction as the relative movement direction of the liquid ejecting head with respect to the wiping member, and the nozzle surface and the wiping member are A liquid ejecting apparatus that wipes the nozzle surface in a state where the relative movement speed of the nozzle is substantially zero has been developed (for example, Patent Document 1). Thereby, it can suppress that the liquid-repellent film formed in the nozzle surface wears.

JP-A-6-155754

  However, even if the nozzle surface is wiped off, ink may remain on the nozzle surface. For example, when the ink adhering to the nozzle surface thickens and adheres to the nozzle surface, it becomes difficult to wipe with the wiping member. Further, when such ink is further dried, it adheres to the nozzle surface and becomes more difficult to wipe off. In particular, in the wiping method in which the frictional force between the nozzle surface and the wiping member is reduced as described above, there is a possibility that the thickened ink or the fixed matter remaining on the nozzle surface cannot be sufficiently removed. .

  The present invention has been made in view of such circumstances, and an object thereof is to provide a liquid ejecting apparatus capable of wiping the nozzle surface while reducing the frictional force between the nozzle surface and the wiping member. .

The present invention has been proposed in order to achieve the above object, and a liquid ejecting head in which a nozzle row including a plurality of nozzles is formed on a nozzle surface and ejects liquid from the nozzles;
A wiping unit having a liquid-retaining wiping member,
The first region of the wiping member wetted by landing of the liquid ejected from the nozzle comes into contact with the nozzle region including the nozzle row of the nozzle surface, and deviates from the first region of the wiping member. The second region is in contact with the non-nozzle region outside the nozzle region of the nozzle surface,
The first area wipes the nozzle area and the second area wipes the non-nozzle area while the liquid ejecting head and the wiping unit move relative to each other in the nozzle row direction. To do.

  According to the present invention, since the nozzle area is wiped by the first area moistened with the liquid, the frictional force between the nozzle area and the wiping member can be reduced. Thereby, for example, it is possible to suppress deterioration of the liquid repellent film formed in the vicinity of the nozzle on the nozzle surface, and it is possible to suppress the liquid from adhering to the vicinity of the nozzle. As a result, it is possible to suppress the occurrence of ejection failure such as liquid flight bending. Further, since the non-nozzle area is wiped in the second area not wetted with the liquid, the frictional force between the non-nozzle area and the wiping member can be increased as compared with the nozzle area. Thereby, the foreign material, the thickened material, or the fixed material adhered to the nozzle surface can be more reliably removed. As a result, it is possible to improve the adhesion of the cap that seals the nozzle surface to the nozzle surface in order to suppress the evaporation of the liquid solvent from the nozzle, and suppress the increase in the viscosity of the liquid in a standby state where no liquid is ejected. can do.

In the above configuration, the apparatus includes a wiping member moving unit that moves the wiping member relative to the nozzle surface in the nozzle row direction,
When wiping the nozzle surface, the wiping member is placed on the nozzle surface in the same direction as the relative movement direction of the liquid ejecting head with respect to the wiping unit at the same speed as the relative movement speed of the liquid ejecting head with respect to the wiping unit. It is desirable to move it.

  According to this configuration, the relative movement speed between the nozzle surface and the wiping member can be made substantially zero, and the frictional force between the nozzle surface and the wiping member can be further reduced. As a result, the deterioration of the liquid repellent film can be further suppressed.

Further, the wiping member moving means for moving the wiping member relative to the nozzle surface in the nozzle row direction,
When wiping the nozzle surface, it is preferable that the wiping member is moved relative to the nozzle surface in a direction opposite to a relative movement direction of the liquid ejecting head with respect to the wiping unit.

  According to this configuration, the relative movement speed between the nozzle surface and the wiping member can be increased, and the frictional force between the nozzle surface and the wiping member can be further increased. As a result, it is possible to more reliably remove foreign matter, thickened matter, fixed matter, etc. adhering to the nozzle surface.

Further, in each of the above configurations, a pressing member that contacts the nozzle surface of the wiping member opposite to the nozzle surface and presses the wiping member to the nozzle surface side,
It is desirable to adjust the pressing force of the wiping member against the nozzle surface by adjusting the pressing force by the pressing member.

  According to this configuration, for example, when there is little adherence of sticking matter or the like and it is desired to suppress deterioration of the liquid repellent film, the pressing force of the wiping member against the nozzle surface is weakened, and foreign matter, thickened material or solid matter attached to the nozzle surface is reduced. When it is desired to remove the kimono and the like more reliably, the pressing force of the wiping member against the nozzle surface can be increased. That is, the frictional force between the nozzle surface and the wiping member can be adjusted according to the state of the nozzle surface. Moreover, when the wiping member is a cloth or the like made of a plurality of fibers, the interval between the fibers constituting the wiping member can be adjusted by changing the pressing force of the wiping member. Thereby, the degree of penetration of the liquid into the wiping member can be adjusted, and the width of the first region can be adjusted. As a result, for example, it is possible to suppress the change in the width of the first region due to a difference in characteristics such as the viscosity of the liquid, and it is possible to more reliably wipe the region near the nozzle. Further, by arbitrarily adjusting the width of the first region, it is possible to adjust the region where the frictional force is desired to be reduced during wiping.

  Furthermore, in each of the above-described configurations, it is desirable to adjust the width of the first region by adjusting the amount of liquid that lands on the wiping member.

  According to this configuration, it is possible to suppress the change in the width of the first region due to the difference in characteristics such as the viscosity of the liquid, and it is possible to wipe out the region near the nozzle more reliably. Further, by arbitrarily adjusting the width of the first region, it is possible to adjust the region where the frictional force is desired to be reduced during wiping.

2A and 2B are schematic diagrams illustrating a configuration of a printer, in which FIG. 1A is a cross-sectional view, and FIG. FIG. 3 is a cross-sectional view of a recording head. It is a wave form diagram explaining an example of an injection pulse. FIG. 3 is a plan view illustrating a configuration on a nozzle surface side of a recording head. It is a top view explaining the structure by the side of the recording head of a wiping member. It is the schematic explaining a wiping unit, (a) is sectional drawing of the state in which the wiping member is not contact | abutting to a nozzle surface, (b) is sectional drawing of the state in which the wiping member was contact | abutted to the nozzle surface.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention will be described with reference to the accompanying drawings. In the embodiments described below, various limitations are made as preferred specific examples of the present invention. However, the scope of the present invention is not limited to the following description unless otherwise specified. However, the present invention is not limited to these embodiments. In the following description, an ink jet printer (hereinafter referred to as a printer) equipped with an ink jet recording head (hereinafter referred to as a recording head), which is a kind of liquid ejecting head, is taken as an example of the liquid ejecting apparatus of the present invention.

  The configuration of the printer 1 will be described with reference to FIG. The printer 1 is a device that records an image or the like by ejecting liquid ink onto the surface of a recording medium 2 (a kind of landing target) such as recording paper. The printer 1 includes a recording head 3, a carriage 4 to which the recording head 3 is attached, a carriage moving mechanism 5 that moves the carriage 4 in the main scanning direction, a conveyance mechanism 6 that transfers the recording medium 2 in the sub scanning direction, and the like. Yes. Here, the ink is a kind of liquid of the present invention, and is stored in an ink cartridge 7 as a liquid supply source. The ink cartridge 7 is detachably attached to the recording head 3. It is also possible to employ a configuration in which the ink cartridge is disposed on the main body side of the printer and supplied from the ink cartridge to the recording head through the ink supply tube.

  The carriage moving mechanism 5 includes a timing belt (not shown), a guide rod 5a, and the like. The timing belt is driven by a pulse motor (not shown) such as a DC motor. The guide rod 5 a is installed inside the printer 1 along the main scanning direction X (the width direction of the recording medium 2). Therefore, when the pulse motor operates, the carriage 4 is guided by the guide rod 5a and reciprocates in the main scanning direction X. The position of the carriage 4 in the main scanning direction X is detected by a linear encoder (not shown) which is a kind of position information detecting means. The linear encoder transmits the detection signal, that is, the encoder pulse (a kind of position information) to the control unit of the printer 1. The transport mechanism 6 includes a plurality of rollers and a drive source (not shown). In the present embodiment, the recording medium 2 is accommodated in a paper feed tray 8 provided below the printer 1, and the recording medium 2 is moved from the paper feed tray 8 one by one by driving each roller of the transport mechanism 6. Guided up.

  In addition, a home position serving as a base point for scanning of the carriage 4 is set in one end area (on the right side in FIG. 1B) outside the recording area within the movement range of the carriage 4. . In this home position, in order from one end side, there are a cap 12 for sealing the nozzle 22 formed on the nozzle surface 28 (nozzle plate 21) of the recording head 3, and a wiping unit 11 for wiping the nozzle surface 28. Has been placed. The cap 12 is formed in a tray shape having an open surface on the side in contact with the nozzle surface 28. The cap 12 is configured to be convertible between a capping state in which the nozzle 22 is sealed by abutting against the nozzle surface 28 and a retracted state separated from the nozzle surface 28. The printer 1 records in both directions, when the carriage 4 moves from the home position toward the opposite end, and when the carriage 4 returns from the opposite end to the home position. So-called bidirectional recording is performed in which characters, images, and the like are recorded on the medium 2. The configuration of the wiping unit 11 and the wiping operation of the nozzle surface 28 by the wiping unit 11 will be described later.

  Next, the recording head 3 will be described. FIG. 2 is a schematic cross-sectional view of the recording head 3, and FIG. 4 is a plan view illustrating the configuration of the nozzle plate 21. In FIG. 2, the configuration of the main part corresponding to one nozzle row 23 is shown. As shown in FIG. 2, the recording head 3 in the present embodiment includes a pressure generating unit 14 and a flow path unit 15, and is configured by being attached to a case 18 in a state where these members are laminated.

  The case 18 is a box-shaped member made of synthetic resin, and an ink introduction path 19 is formed therein. The flow path unit 15 includes a nozzle plate 21 in which a plurality of nozzles 22 are opened in a straight line (row shape) and a communication substrate 24 provided with a liquid supply flow path 25. The plurality of nozzles 22 (nozzle row 23) arranged in a row are sub-scanned perpendicular to the main scanning direction X at a pitch (for example, 180 dpi) corresponding to the dot formation density from the nozzle 22 on one end side to the nozzle 22 on the other end side. It is provided at equal intervals along the direction (nozzle row direction Y). In the present embodiment, as shown in FIG. 4, eight nozzle rows 23 a to 23 h (a kind of nozzle group) are arranged in parallel in the main scanning direction X. The lower surface of the nozzle plate 21 corresponds to the nozzle surface 28. An ink repellent film is formed on the nozzle surface 28. Thereby, it can suppress that the ink adhering to the nozzle surface 28 spreads.

  Each of the nozzle rows 23a to 23h is assigned a different kind (color) of ink, for example, one of black ink, cyan ink, magenta ink, yellow ink, and white ink. In other words, different types (colors) of ink are ejected from the nozzle rows 23a to 23h. The white ink is, for example, an ink for forming a base, and an ink containing titanium dioxide or the like having an average particle diameter of about 200 to 400 nm as a pigment is preferably used. As the black ink, an ink containing carbon black having an average particle diameter of about 160 nm is preferably used. In addition, color inks such as cyan ink, magenta ink, and yellow ink have an average particle diameter of the contained pigment of about 10 to 75 nm.

  The pressure generating unit 14 is unitized by stacking a pressure chamber forming substrate 29 on which a pressure chamber 30 is formed, an elastic film 31, a piezoelectric element 32, and a protective substrate 33. Then, ink from the ink cartridge 7 is introduced into the pressure chamber 30 via the ink introduction path 19 and the liquid supply path 25, and a drive signal (ejection pulse) from the control unit is supplied to the piezoelectric element 32, thereby The element 32 is driven to cause a pressure fluctuation in the pressure chamber 30. By utilizing this pressure fluctuation, ink droplets are ejected from the nozzle 22 via the nozzle communication path 35 of the communication substrate 24.

  FIG. 3 shows an example of an ejection pulse (voltage waveform) for driving the piezoelectric element 32. In FIG. 3, the vertical axis represents voltage, and the horizontal axis represents time. The injection pulse includes an expansion element p1, an expansion maintenance element p2, a contraction element p3, a contraction maintenance element p4, and a return element p5. The expansion element p1 expands the pressure chamber 30 by changing the potential from the reference potential (intermediate potential) VB to the minimum potential (minimum voltage) VL in the negative direction. The expansion maintaining element p2 maintains the minimum potential VL for a certain time. The contraction element p3 rapidly contracts the pressure chamber 30 by changing the potential from the minimum potential VL to the maximum potential (maximum voltage) VH in the positive direction. The contraction maintaining element p4 maintains the maximum potential VH for a certain time. The return element p5 returns the potential from the maximum potential VH to the reference potential VB. In such an ejection pulse, the amount of ink ejected from the nozzle 22 varies depending on the potential difference Vd between the minimum potential VL and the maximum potential VH (the amount of voltage change of the contraction element p3). For example, when it is desired to increase the amount of ink ejected from the nozzle 22 (in the case of a large dot), an ejection pulse having a large potential difference Vd between the minimum potential VL and the maximum potential VH is used. On the other hand, when it is desired to reduce the amount of ink ejected from the nozzle 22 (in the case of small dots), an ejection pulse having a small potential difference Vd between the minimum potential VL and the maximum potential VH is used. In addition, the ejection pulse is not limited to the illustrated waveform, but can be an ejection pulse that ejects ink corresponding to each dot size using waveforms having various configurations.

  Next, the wiping unit 11 will be described. FIG. 5 is a plan view of the wiping member 37 constituting the wiping unit 11 as seen from the surface on the recording head 3 side. 6A is a schematic sectional view of the wiping unit 11 in a state where the wiping member 37 is not in contact with the nozzle surface 28, and FIG. 6B is a state in which the wiping member 37 is in contact with the nozzle surface 28. It is a cross-sectional schematic diagram of the wiping unit 11.

  As shown in FIG. 6, the wiping unit 11 of the present embodiment includes an endless sheet-like wiping member 37 having ink retaining properties (liquid retaining properties) and two rotating rollers 38 a on which the wiping member 37 is stretched. , 38b and the rotation roller 38a, 38b abuts against the nozzle surface 28 of the wiping member 37 and presses the wiping member 37 against the nozzle surface 28 (the pressing member in the present invention). And a box-shaped unit base 41 to which the rotation rollers 38a and 38b and the pressing roller 40 are attached. The wiping member 37 is made of, for example, a cloth made of fibers such as cotton, silk, glass, and metal, and can hold ink between the fibers. In the wiping member 37 of the present embodiment, the length (dimension) in the direction orthogonal to the nozzle row 23 (main scanning direction X) is longer than the length (dimension) in the same direction of the nozzle surface 28 of the recording head 3. Yes. One of the rotation rollers 38a and 38b is a drive roller provided with a drive source (not shown), and the other is a driven roller that is pivotally supported so as to freely rotate. As shown in FIG. 5, the rotation rollers 38 a and 38 b have the axial direction aligned with the main scanning direction X, and the length (dimension) in the same direction is aligned with the length (dimension) of the wiping member 37. Further, the interval between the central axes of both the rotating rollers 38a and 38b is set to be longer than the length (dimension) of the nozzle surface 28 of the recording head 3 in the nozzle row direction Y (sub-scanning direction). For this reason, the length in the nozzle row direction Y of the wiping member 37 stretched between the rotating rollers 38a and 38b is longer than the length of the nozzle surface 28 of the recording head 3 in the same direction. That is, in this embodiment, the area of the upper surface (contact surface with the recording head 3) of the wiping member 37 that is stretched is larger than the area of the nozzle surface 28 of the recording head 3. The rotating rollers 38a and 38b correspond to the wiping member moving means in the present invention.

  The pressing roller 40 is pivotally supported freely and can be moved in the vertical direction with respect to the unit base 41 (in the direction perpendicular to the nozzle surface 28), for example, by a cam. A drive mechanism (not shown) for moving up and down is provided. When the nozzle surface 28 is not wiped by the wiping member 37, the pressing roller 40 has a vertical position (height) with respect to the unit base 41 as shown in FIG. 6A. Are aligned at the same position (height). That is, in this case, the wiping member 37 is not pressed by the pressing roller 40. Then, as shown in FIG. 6B, when the nozzle surface 28 is wiped by the wiping member 37, the wiping member 37 is pressed toward the nozzle surface 28 by driving the drive mechanism and moving upward. . At this time, by adjusting the position (height) of the pressing roller 40, the pressing force of the pressing roller 40 against the wiping member 37 can be adjusted, and the pressing force of the wiping member 37 against the nozzle surface 28 can be adjusted. it can.

  The unit base 41 is a box-like member having an open upper surface that accommodates the lower portions of the rotation rollers 38 a and 38 b and the pressing roller 40. The wiping unit 11 of the present embodiment moves the unit base 41 (that is, the wiping unit 11 itself) in the nozzle row direction Y in a plane parallel to the nozzle surface 28, for example, a wiping unit using a ball spline. A moving means (not shown) is provided. As shown in FIG. 6B, the wiping unit moving means moves the wiping unit 11 to the nozzle surface 28 (recording head 3) with the wiping unit 37 in contact with the nozzle surface 28. The relative movement is made in the column direction Y. As a result, the entire nozzle surface 28 can be wiped off.

  Next, the wiping operation by the wiping unit 11 will be described. In the wiping operation of the present invention, the nozzle region An including the nozzle row 23 on the nozzle surface 28 as shown in FIG. 4 (the region near the nozzle 22 along the nozzle row 23) and the nozzle region An on the nozzle surface 28 are not separated. It is characterized in that the frictional force applied at the time of wiping is different between the nozzle area Aa (area not including the nozzles 22 along the nozzle row 23). The wiping operation is performed, for example, after a certain time has elapsed or after ejecting ink from the nozzle 22 a certain number of times or more.

  Specifically, first, the carriage 4 is placed on standby above the wiping member 37 at the home position, and the nozzle surface 28 and the wiping member 37 are made to face each other. In this state, ink droplets are ejected from each nozzle 22 and land on the wiping member 37. As a result, the first region W facing the nozzle region An is moistened by the landed ink. At this time, the wiping member 37 is ejected by rotating (driving) the rotating rollers 38 a and 38 b and ejecting ink droplets while moving the wiping member 37 relative to the recording head 3 in the nozzle row direction Y. The entire surface in the nozzle row direction Y may be moistened. In the present embodiment, as shown in FIG. 5, the first region W moistened with ink is formed in eight stripes corresponding to the eight nozzle rows 23, and the ink separated from the first region W Nine second regions D that are not moistened by are formed. Then, before the landed ink dries, the pressing roller 40 is moved upward to bring the wiping member 37 into contact with one end of the nozzle surface 28. Accordingly, a part of the first region W abuts on one side end of the nozzle region An of the nozzle surface 28, and a part of the second region D is one side end of the non-nozzle region Aa of the nozzle surface 28. Abut.

  In this state, as shown in FIG. 6B, the wiping unit moving means is driven to move the wiping unit 11 relatively in the nozzle row direction Y toward the other end of the nozzle surface 28. At the same time, the rotation rollers 38 a and 38 b are rotated to move the wiping member 37 relative to the nozzle surface 28 in the nozzle row direction Y. In the present embodiment, the wiping member 37 is moved relative to the nozzle surface 28 in the same direction as the relative movement direction of the recording head 3 relative to the wiping unit 11 at the same speed as the relative movement speed of the recording head 3 relative to the wiping unit 11. Thereby, the relative moving speed of the nozzle surface 28 and the wiping member 37 can be made substantially zero. The nozzle region An can be wiped off by the wet first region W, and the non-nozzle region Aa can be wiped off by the non-wet second region D. Alternatively, the wiping unit 11 may be reciprocated with respect to the nozzle surface 28 to wipe the nozzle surface 28 a plurality of times. At this time, the movement of the wiping member 37 in accordance with the change in the relative movement speed and the relative movement direction between the wiping unit 11 and the recording head 3 so that the relative movement speed between the nozzle surface 28 and the wiping member 37 becomes substantially zero. Velocity and direction of movement are also changed. When the entire nozzle surface 28 is wiped, the movement of the wiping unit 11 and the rotation of the rotation rollers 38a and 38b are stopped, and the pressing roller 40 is moved downward to complete the wiping operation.

  As described above, since the nozzle region An is wiped by the first region W moistened with ink, the frictional force between the nozzle region An and the wiping member 37 can be reduced. Thereby, it is possible to suppress deterioration of the ink repellent film formed in the vicinity of the nozzle 22 on the nozzle surface 28, and it is possible to suppress ink from adhering to the vicinity of the nozzle 22. As a result, it is possible to suppress the occurrence of ejection failure such as ink flight bending. Further, since the non-nozzle region Aa is wiped in the second region D not wetted with the liquid, the frictional force between the non-nozzle region Aa and the wiping member 37 can be increased as compared with the nozzle region An. it can. Thereby, the foreign material, the thickened material, the fixed material, or the like attached to the nozzle surface 28 can be more reliably removed. As a result, it is possible to improve the adhesion of the cap 12 that seals the nozzle surface 28 to the nozzle surface 28 in order to prevent the ink solvent from evaporating from the nozzle 22, and the ink in the standby state in which ink is not ejected. Thickening can be suppressed. Further, when wiping the nozzle surface 28, the wiping member 37 is placed on the nozzle surface 28 in the same direction as the relative movement direction of the recording head 3 with respect to the wiping unit 11 at the same speed as the relative movement speed of the recording head 3 with respect to the wiping unit 11. Therefore, the relative movement speed between the nozzle surface 28 and the wiping member 37 can be made substantially zero, and the frictional force between the nozzle surface 28 and the wiping member 37 can be further reduced. As a result, the deterioration of the ink repellent film can be further suppressed.

  By the way, in the said embodiment, although the relative moving speed of the nozzle surface 28 and the wiping member 37 was made substantially zero, and the nozzle surface 28 was wiped off, it is not restricted to this. For example, when wiping the nozzle surface 28, the rotation rollers 38 a and 38 b are rotated to move the wiping member 37 relative to the nozzle surface 28 in the direction opposite to the relative movement direction of the recording head 3 with respect to the wiping unit 11. By moving, the relative movement speed between the nozzle surface 28 and the wiping member 37 can be made faster than the relative movement speed between the wiping unit 11 and the recording head 3. In this way, the frictional force between the nozzle surface 28 and the wiping member 37 can be further increased. As a result, it is possible to more reliably remove foreign matter, thickened matter, fixed matter, etc. adhering to the nozzle surface 28. In addition, the relative movement speed between the nozzle surface 28 and the wiping member 37 can be arbitrarily adjusted by controlling the rotation direction and the rotation speed of the rotation rollers 38a and 38b. Thereby, the frictional force between the nozzle surface 28 and the wiping member 37 can be adjusted.

  Moreover, the frictional force between the nozzle surface 28 and the wiping member 37 can also be adjusted by adjusting the pressing force of the pressing roller 40. Thereby, the wiping according to the state of the nozzle surface 28 is attained. For example, when there is little adherence of sticking matter or the like and it is desired to suppress the deterioration of the ink repellent film, the pressing force of the wiping member 37 against the nozzle surface 28 is weakened to remove foreign matter, thickened matter, or sticking matter attached to the nozzle surface 28. When it is desired to remove more reliably, the pressing force of the wiping member 37 against the nozzle surface 28 can be increased. Furthermore, in addition to the adjustment of the pressing force of the pressing roller 40, the frictional force between the nozzle surface 28 and the wiping member 37 is adjusted more finely by adjusting the relative movement speed between the nozzle surface 28 and the wiping member 37. be able to.

  Further, by adjusting the pressing force of the pressing roller 40 and changing the pressing force applied to the wiping member 37, the interval between the fibers constituting the wiping member 37 can be adjusted. As a result, the degree of ink penetration into the wiping member 37 can be adjusted, and the width of the first region can be adjusted. As a result, for example, it is possible to suppress a change in the width of the first region due to a difference in characteristics such as the viscosity of the ink, and it is possible to wipe the region near the nozzle 22 more reliably. Further, by arbitrarily adjusting the width of the first region W, it is possible to arbitrarily adjust the width of the region where the frictional force is desired to be reduced during wiping (the nozzle region An wiped by the first region W). In the above embodiment, ink is landed on the wiping member 37 in a state where the pressing roller 40 is not pressing the wiping member 37, but the present invention is not limited to this. In the state where the pressing roller 40 is pressing the wiping member 37, ink may be landed on the wiping member 37.

  Furthermore, the method of adjusting the width of the first region W is not limited to the method of pressing the wiping member 37. The width of the first region W can be adjusted by adjusting the amount of ink droplets ejected from the nozzles 22 and adjusting the amount of ink droplets that land on the wiping member 37. For example, when it is desired to increase the width of the first region W, an ejection pulse corresponding to a large dot is applied to the piezoelectric element 32. Further, when it is desired to narrow the width of the first region W, an ejection pulse corresponding to a small dot is applied to the piezoelectric element 32. In addition, the width of the first region W can be adjusted by increasing or decreasing the number of times ink is ejected.

  In the above embodiment, the wiping unit 11 is moved relative to the recording head 3 in the nozzle row direction Y by the wiping unit moving unit. However, the present invention is not limited to this. For example, a carriage moving unit that moves the carriage in the nozzle row direction Y may be provided, and the recording head may be moved relative to the wiping unit in the nozzle row direction Y by the carriage moving unit. Moreover, in the said embodiment, although the nozzle row 23 was formed in 8 rows, it is not restricted to this, What is necessary is just to form at least 1 row.

  Furthermore, in the said embodiment, the ink was ejected with respect to the wiping member 37, and the 1st area | region W corresponding to all the nozzle rows 23 (nozzle area | region An) was moistened, However, It is not restricted to this. For example, according to the average particle diameter of the pigment contained in the ink ejected from the nozzle row 23, whether or not to wipe the nozzle row 23 in the wet first region W may be set. Here, when the average particle size of the pigment contained in the ink is large, the frictional force between the first region W moistened with the ink and the nozzle surface 28 may increase. Therefore, only the nozzle row 23 corresponding to the ink having an average particle diameter of the contained pigment is ejected to the wiping member 37, and the nozzle region An in the vicinity of the nozzle row 23 is covered with the ink. It is desirable to wipe off the moistened first region W. For example, only the nozzle region An in the vicinity of the nozzle row 23 corresponding to cyan ink, magenta ink, and yellow ink having an average particle diameter of the contained pigment of 100 nm or less is wiped with the first region W moistened with the ink. The nozzle region An in the vicinity of the nozzle row 23 corresponding to white ink and black ink having an average particle diameter of the contained pigment of 100 nm or more is wiped with the second region D that is not moistened with ink. Thereby, deterioration of the ink repellent film can be further suppressed.

  In the above-described embodiment, the ink jet printer provided with the ink jet recording head has been exemplified. However, the present invention can also be applied to an apparatus that ejects liquid other than ink. For example, a color material ejecting head used for manufacturing a color filter such as a liquid crystal display, an electrode material ejecting head used for forming an electrode such as an organic EL (Electro Luminescence) display, FED (surface emitting display), a biochip (biochemical element) The present invention can also be applied to a liquid ejecting apparatus including a bio-organic matter ejecting head and the like used for manufacturing.

  DESCRIPTION OF SYMBOLS 1 ... Printer, 3 ... Recording head, 4 ... Carriage, 5 ... Carriage moving mechanism, 6 ... Conveyance mechanism, 7 ... Ink cartridge, 11 ... Wiping unit, 12 ... Cap, 14 ... Pressure generating unit, 15 ... Flow path unit, 21 ... Nozzle plate, 22 ... Nozzle, 23 ... Nozzle row, 28 ... Nozzle surface, 37 ... Wiping member, 38 ... Rotating roller, 40 ... Pressing roller, 41 ... Unit base

Claims (5)

A nozzle row including a plurality of nozzles is formed on a nozzle surface, and a liquid ejecting head that ejects liquid from the nozzles;
A wiping unit having a liquid-retaining wiping member,
The first region of the wiping member wetted by landing of the liquid ejected from the nozzle comes into contact with the nozzle region including the nozzle row of the nozzle surface, and deviates from the first region of the wiping member. The second region is in contact with the non-nozzle region outside the nozzle region of the nozzle surface,
The first area wipes the nozzle area and the second area wipes the non-nozzle area while the liquid ejecting head and the wiping unit move relative to each other in the nozzle row direction. Liquid ejecting device. Wiping member moving means for moving the wiping member relative to the nozzle surface in the nozzle row direction,
When wiping the nozzle surface, the wiping member is placed on the nozzle surface in the same direction as the relative movement direction of the liquid ejecting head with respect to the wiping unit at the same speed as the relative movement speed of the liquid ejecting head with respect to the wiping unit. The liquid ejecting apparatus according to claim 1, wherein the liquid ejecting apparatus is moved. Wiping member moving means for moving the wiping member relative to the nozzle surface in the nozzle row direction,
2. The wiping member is moved with respect to the nozzle surface in a direction opposite to a relative movement direction of the liquid ejecting head with respect to the wiping unit when the nozzle surface is wiped. Liquid ejector. A pressing member that abuts on the side opposite to the nozzle surface of the wiping member and presses the wiping member toward the nozzle surface;
4. The liquid ejecting apparatus according to claim 1, wherein a pressing force of the wiping member with respect to the nozzle surface is adjusted by adjusting a pressing force by the pressing member. 5.   5. The liquid ejecting apparatus according to claim 1, wherein the width of the first region is adjusted by adjusting an amount of liquid landed on the wiping member. 6.

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