JP2006062263A - Ink-jet recording device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To realize an ink-jet recording device which can safely execute capping without damaging a nozzle even when the nozzle is protected by using a cap member composed of a material having a small elastic deformation amount. <P>SOLUTION: The ink-jet recording device is provided with the nozzle 44 for discharging ink to a glass substrate, a cap unit for protecting the nozzle when the ink is not discharged, a position detection sensor, which detects a position of the glass substrate when the ink is discharged and also detects a position of the cap unit when the ink is not discharged, and a drive device for moving the nozzle on the basis of the detection results of the position detection sensor. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an ink jet recording apparatus. More specifically, the present invention relates to an ink jet recording apparatus that can accurately position an ink discharge portion with respect to a protection member when the ink discharge portion is protected by a protection member when ink is not discharged.

  In recent years, the field of application of ink jet recording apparatuses has been extended not only to paper printing but also to other fields such as substrate circuit fabrication. In particular, in the field of manufacturing thin displays, attention has been paid to a method of manufacturing wiring and color filters for liquid crystal displays and organic EL elements for organic EL displays using an inkjet recording apparatus. This is also due to the high expectation of high cost performance due to the fact that the use condition of the ink jet recording apparatus does not require a vacuum state.

  In addition, when the inkjet recording apparatus is not in use, if the nozzles of the inkjet head that ejects ink are left exposed for a long time, the ink will evaporate, dry, stick, or thicken, and so on. Ink may not be ejected properly or may not be possible. For this reason, generally, when the ink jet recording apparatus is not used, the ink ejection opening of the nozzle is covered with a cap. Of course, it is preferable that the nozzle is sealed with this cap to have high sealing performance. Such a technique of covering the nozzle with a cap is disclosed in, for example, Patent Documents 1 to 5.

  Patent Document 1 describes an ink jet head cap device. This cap device has a configuration in which a core member made of a material having high rigidity is fitted in an empty chamber formed inside a cap member made of an elastic body. Thereby, the airtightness of an inkjet head and a cap member is improved.

  Patent Document 2 describes an ink suction cap. This ink suction cap is provided with a pressing member formed of an elastic material having a height lower than the inner height at the inner bottom portion of the cap formed of an elastic material, and the nozzle can be sealed with the pressing member when printing is suspended. It is like that.

  Patent Document 3 describes an ink jet recording apparatus that includes an elongated track-shaped rubber cap member for capping an injection nozzle, and the height of an arc portion of the rubber cap member is higher than that of a linear portion. By making the height of the arc portion higher than that of the straight portion, the adhesion between the head surface and the rubber cap surface is ensured without increasing the spring load that presses the rubber cap surface against the head surface.

  Patent Document 4 describes a cap for a printer head. In Patent Document 4, the portion where the cap is in contact with the nozzle surface of the printer head is formed into a shape consisting of a long side portion and a short side portion, and the long side portion, which is difficult to obtain accuracy, is made flexible compared to the short side portion, In addition, the height of the long side portion is higher than that of the short side portion. Thereby, the adhesiveness of a cap and a nozzle surface is maintained.

Japanese Patent Application Laid-Open No. 2004-228688 includes a capping member having an elastic member that seals the nozzle forming surface in close contact with the nozzle forming surface of a recording head, and has a rib formed to restrict the displacement of the elastic member at the time of sealing. A property maintaining device is described. With this configuration, after the entire circumference of the contact surface of the elastic member of the capping member is uniformly crushed with an appropriate pressing force, the upper surface of each rib contacts the nozzle forming surface and the contact surface is further crushed. The nozzle forming surface is always reliably sealed.
JP-A-4-14461 (published January 20, 1992) Japanese Patent Laid-Open No. 5-77433 (published on March 30, 1993) JP-A-5-318752 (published on December 3, 1993) Japanese Patent Laid-Open No. 6-155753 (published June 3, 1994) Japanese Patent Laying-Open No. 2004-9558 (Released on January 15, 2004)

  However, as ink jet recording apparatuses are applied to production apparatuses such as substrate circuit production, inks made of various materials have come to be used. Along with this, organic solvents having higher dissolving power have been used as solvents for ink materials, such as water and alcohol. As a result, the ink jet recording apparatus needs to have chemical resistance, and the cap that covers the ink discharge port of the nozzle is particularly necessary.

  However, since the ink discharge port needs to be sealed when the ink jet recording apparatus is not used, the cap needs to be elastically deformed to make complete contact with the ink discharge port surface. However, in general, the chemical resistance and elasticity tend to conflict. For this reason, in many cases, the cap is made of a material having a chemical resistance by compromising the elastic performance.

  When such a material is used, since the elastic deformation of the cap is not sufficiently performed, a positioning margin between the ink discharge port surface and the cap when the cap moves to the capping position (cap and ink discharge port surface) If the distance between the first contact and the relative movement between the inkjet head and the cap is increased, the nozzle will be damaged. In order to avoid this, it is necessary to reduce the positioning margin.

  This margin amount is greatly influenced by the accuracy of the ink jet recording apparatus, particularly the positioning accuracy of the ink discharge ports. However, due to the increase in size and complexity of the inkjet recording apparatus accompanying the increase in the size of the substrate for performing inkjet, the positioning accuracy during capping has deteriorated, resulting in an increased risk of nozzle breakage. have.

  For example, in the configuration of Patent Document 1, perfluoro rubber having excellent chemical resistance is used as a cap member although the cap member must have sufficiently low rigidity with respect to the core member. For this reason, the cap member is not sufficiently deformed, and the nozzle surface of the inkjet head may be damaged before it is supported by the core member.

  Further, in the configuration of Patent Document 2, when a low elasticity material such as perflo rubber is used as the ink suction cap, the ink suction cap may damage the nozzle surface before the pressing member comes into close contact with the nozzle. is there.

  Similarly, in the configuration of Patent Document 3, when a low-elastic material such as perflo rubber is used as the rubber cap member, the arc portion may damage the head surface before the linear portion comes into close contact with the head surface. There is. Moreover, in the structure of patent document 4, when a low elasticity material, such as a perflo rubber, is used as a cap, before a short side part closely_contact | adheres to a nozzle surface, a long side part may damage a nozzle surface. is there. Furthermore, in the configuration of Patent Document 5, when a low-elasticity material such as perflo rubber is used as the elastic member of the capping member, the elastic member of the capping member causes the nozzle formation surface to come into contact before the upper surface of the rib contacts the nozzle formation surface. It may be damaged.

  The present invention has been made in view of the above-described problems, and the object thereof is a case where a cap member made of a material having a small elastic deformation amount is used as a cap member for protecting the nozzle of the inkjet head. An object of the present invention is to realize an ink jet recording apparatus capable of safely protecting a nozzle without damaging the nozzle.

  In order to solve the above problems, an ink jet recording apparatus according to the present invention includes an ink ejecting unit that ejects ink onto a recording medium and an ink jet recording unit that protects the ink ejecting unit when ink is not ejected. In the apparatus, the position of the recording medium is detected when ink is ejected, and the position of the protection means is detected when ink is not ejected, and the ink ejecting means is moved based on the detection result of the position detecting means. And a moving means.

  According to the above configuration, the ink ejecting means ejects ink onto the recording medium when ink is ejected. As a result, a predetermined image or the like can be formed on the recording medium. Further, when the ink is not ejected, the ink ejecting means is protected by the protecting means. For example, a cap member can be used as the protection means. The ink discharge means can be protected by covering the ink discharge means with the cap member and sealing it. Thereby, even when the ink is not ejected, the ink can be prevented from evaporating, drying, fixing or thickening, and the subsequent ink ejection can be performed appropriately.

  In addition, when ink is ejected, the position detecting unit can detect a positional shift accompanying a change in shape such as slight bending or waviness of the recording medium. Therefore, the moving unit can move the ink discharge unit to an appropriate position for discharging ink to the recording medium. As a result, the ink discharge means can always discharge ink appropriately to the recording medium.

  On the other hand, when the ink is not ejected, the position detection unit can detect the position of the protection unit. For this reason, the moving means can be moved to an optimal position where the ink discharging means is protected by the protection means.

  In other words, even if the optimum position of the ink ejection means during ink ejection differs from the optimum position of the ink ejection means during non-ejection, the ink ejection means is moved to the optimum position in any case. It becomes possible to make it. Accordingly, the movement of the ink discharge means can be controlled accurately and reliably.

  Accordingly, even when the protection means is made of a material having a small elastic deformation amount, for example, the ink discharge means can be prevented from contacting the protection means more than necessary when the ink is not discharged. It is possible to prevent the means from being damaged. As a result, an ink jet recording apparatus that protects the ink discharge means accurately and reliably can be obtained.

  In the ink jet recording apparatus according to the present invention, the protection unit includes a reflection unit that reflects light, and the position detection unit includes a light emitting unit that emits light to the recording medium or the reflection unit, and a recording medium or It is preferable to include a light receiving means for receiving reflected light from the reflecting means. According to said structure, when detecting the position of a recording medium or a protection means, it becomes possible to detect a position using reflection of light. As a result, the positions of the recording medium and the protection means can be detected more accurately.

  In the ink jet recording apparatus according to the present invention, the light reflectance of the reflecting means is preferably the same as the light reflectance of the recording medium. According to the above configuration, since the light reflectance of the reflecting means and the recording medium is the same, the position can be detected easily and accurately. As a result, the movement of the ink discharge means can be controlled more reliably and accurately, and the ink discharge means can be prevented from being damaged by the protection means when the ink is not discharged. Note that “the light reflectance is the same” means that the light reflectance of the reflecting means is exactly the same as the light reflectance of the recording medium, or that the light reflectance of the reflecting means is reflected by the protecting means. Compared to the light reflectance of the portion other than the means, the value is close to the light reflectance of the recording medium, or the difference between the light reflectance of the reflecting means and the light reflectance of the recording medium is 10%. If it is within.

  In the ink jet recording apparatus according to the present invention, the reflecting means is preferably made of the same material as the recording medium. According to said structure, since the reflection means and the recording medium consist of the same material, it becomes possible to make the reflectance of light the same. Therefore, it is possible to avoid the ink discharge means from being damaged by the protection means.

  In the ink jet recording apparatus according to the present invention, the reflecting means has a distance between the ink ejecting means and the reflecting means in a state where the ink ejecting means is protected by the protecting means. It is preferable to arrange at the same position as the distance. According to the above configuration, the position detecting unit can detect the position of the recording medium when ink is ejected and the position of the reflecting unit when ink is not ejected at substantially the same height (distance). Become. For this reason, when the ink discharge means is protected, the ink discharge means can be moved easily and reliably, and the ink discharge means can be protected accurately.

  As described above, the ink jet recording apparatus according to the present invention detects the position of the recording medium when ink is ejected, and detects the position of the protection means when ink is not ejected, and the detection of the position detecting means. And an ink jet recording apparatus that can prevent the ink ejecting means from being damaged by the protective means and protect the ink ejecting means reliably and accurately. There is an effect that it can be.

  An embodiment of the present invention will be described with reference to FIGS. 1 to 9 as follows. In the present embodiment, a TFT substrate repair device equipped with the ink jet recording apparatus according to the present invention will be described as an example.

  FIG. 2 is a perspective view showing a schematic configuration of the repair device 1 according to the present embodiment. As shown in FIG. 2, the repair apparatus 1 includes a stage unit 10, a correction unit 21, an ink discharge unit (inkjet recording apparatus) 31, and a control unit 71.

  The stage unit 10 includes a stage base 11, a substrate holder 12, a first linear guide 14, and a surface plate unit 15. The substrate holder 12, the first linear guide 14, and the surface plate portion 15 are disposed on the stage base 11. The substrate holder 12 is for placing a glass substrate (recording medium) 13 used for the TFT substrate after the film forming process before repair is completed. The substrate holder 12 is provided with a plurality of small holes, and a pressure reducing device (not shown) is provided closer to the stage base 11 than the substrate holder 12 is. By placing the glass substrate 13 on the substrate holder 12 and reducing the pressure by the decompression device, the glass substrate 13 is attracted and fixed to the substrate holder 12 through the plurality of small holes. Accordingly, when the glass substrate 13 is repaired (when ink is ejected onto the glass substrate 13), it is possible to prevent the glass substrate 13 from moving and being displaced.

  The first linear guide 14 guides the movement of the surface plate portion 15. The first linear guide 14 is composed of a pair of rod-shaped guide members, and each guide member is disposed on the stage base 11 on the end side of the substrate holder 12 in a parallel state.

  The surface plate 15 is a member that is long in a direction (hereinafter referred to as Y direction) orthogonal to the longitudinal direction (hereinafter referred to as X direction) of each guide member of the first linear guide 14. Are arranged so as to mesh with each other. The surface plate 15 moves in the X direction while being guided by each guide member of the first linear guide 14.

  A correction unit 21 and an ink discharge unit 31 which will be described later are attached to the surface plate unit 15. Further, the surface plate unit 15 includes a second linear guide 16 on a surface on which the correction unit 21 and the ink discharge unit 31 are attached (hereinafter referred to as an attachment surface). The second linear guide 16 is for guiding the movement of the correction unit 21 and the ink discharge unit 31. The second linear guide 16 includes a pair of rod-shaped guide members. Each guide member is arranged on the mounting surface of the surface plate 15 in a state where each guide member is parallel to the Y direction. The correction unit 21 and the ink discharge unit 31 are integrally moved on the mounting surface along the second linear guide 16 in the Y direction.

  The correction unit 21 laser-cuts defects on the glass substrate 12 and performs a series of processes such as ink application, drying and baking. The correction unit 21 includes a first back plate 22, a laser cut unit 23, and a moving stage 26. The ink discharge unit 31 discharges ink used for recording on the glass substrate 12. The detailed configuration of the ink discharge unit 31 will be described later.

  The first back plate 22 attaches and fixes the laser cut unit 23 and the ink discharge unit 31 to the surface plate unit 15 so as to be movable. The correction unit 21 and the ink discharge unit 31 are arranged side by side in the Y direction on the first back plate 22. The laser cut unit 23 includes a high-power laser 24, a cutting portion observation microscope 25, and the like. The high-power laser 24 irradiates high-power laser light to cut the glass substrate 13 on the substrate holder 12. The cutting portion observation microscope 25 is a microscope for observing a cut portion of the glass substrate 13. The moving stage 26 is a guide member for moving the laser cut unit 23 and the ink discharge unit 31 in a direction perpendicular to the second linear guide 16 (direction perpendicular to the XY plane; hereinafter referred to as Z direction).

  The control unit 71 controls driving of the entire repair device 1. Specifically, the movement control of the surface plate unit 15, the correction unit 21 and the ink discharge unit 31, and the drive control and determination of the correction unit 21 and the ink discharge unit 31 are performed. The control unit 71 may be configured by a single computer, or may include a plurality of computers and perform each control individually. In the present embodiment, the control unit 71 is disposed at a position away from the stage base 11, and the stage base 11, the correction unit 21, and the ink discharge unit 31 are electrically connected via a cable. .

  Next, the ink discharge unit 31 will be described with reference to FIG. FIG. 3 is a perspective view showing a schematic configuration of the ink discharge unit 31. As shown in FIG. 3, the ink discharge unit 31 includes a second back plate 32, a Z stage (moving means) 33, a ZX joint 34, an X stage (moving means) 35, an XY joint 36, and a Y stage (moving means). 37, repair portion observation optical system 38, radiation thermometer 39, radiation thermometer joint 40, first head joint 41a, second head joint 41b, inkjet unit (ink ejection means) 42, cap unit (protection means) 60, A capping box 61, a bottom plate 65, and the like are provided.

  The second back plate 32 is for fixing the entire ink discharge unit 31 to the first back plate 22. The X stage 35, the Y stage 37, and the Z stage 33 are guide members for moving the inkjet unit 42 in the X direction, the Y direction, and the Z direction, respectively. The ZX joint 34 connects the Z stage 33 and the X stage 35, and the XY joint 36 connects the X stage 35 and the Y stage 37.

  The repair portion observation optical system 38 is an optical system for observing a repair portion (ink discharge portion) of the glass substrate 13 and includes a microscope or the like. The radiation thermometer 39 measures the temperature of the repaired part. The radiation thermometer 39 is connected and fixed to the XY joint 36 via the radiation thermometer joint 40.

  The ink jet unit 42 ejects ink to the glass substrate 13. The ink jet unit 42 is attached to the first head joint 41a, and is connected to the Y stage 37 via the second head joint 41b. Thereby, the inkjet unit 42 can move in three directions of XYZ. A capping box 61 is disposed on the bottom plate, and a cap unit 60 is disposed on the capping box 61.

  Next, the ink jet unit 42, the cap unit 60, and the peripheral portion thereof will be described with reference to FIGS. FIG. 4 is a perspective view illustrating a schematic configuration of the inkjet unit 42, the cap unit 60, and the peripheral portion thereof. FIG. 5 is a perspective view showing a schematic configuration of the ink jet unit 42 viewed from the side opposite to FIG. For ease of explanation, piping, wiring, cable guides, etc. in FIG. 4 are omitted in FIG.

  As shown in FIGS. 4 and 5, the inkjet unit 42 includes an inkjet head 43, a nozzle 44, a head driver 45, an ink tank 46, an ink supply tube 47, and an ink temperature adjustment device 48.

  The inkjet head 43, the head driver 45, and the ink tank 46 are attached to the first head joint 41a. The first head joint 41a has a surface (YZ plane) substantially parallel to the second back plate 32, and the inkjet head 43 and the head driver 45 are connected to the second back plate 22 of the first head joint 41a. Is mounted on the opposite side. The ink tank 46 is attached to the side surface of the first head joint 41a.

  The inkjet head 43 is disposed below the head driver 45 (on the stage unit 10 side). The inkjet head 43 is provided with a nozzle 44 that ejects ink downward (in the direction of the stage unit 10 or the direction of the cap unit 60). That is, the inkjet head 43 is disposed so as to face the stage unit 10 or the cap unit 60.

  The head driver 45 controls the drive of the inkjet head 43. The ink jet head 43 and the head driver 45 are electrically connected by a wiring (not shown). Further, the head driver 45 is electrically connected to the control unit 71 through a wiring (not shown).

  The ink tank 46 has an ink pack that stores an ink solution in which a material to be discharged onto the glass substrate 13 is dissolved. The ink solution in the ink pack is supplied to the nozzle 44 through an ink supply tube 47 that connects the ink tank 46 and the nozzle 44. Further, the inside of the ink tank 46 is pressurized and depressurized by wiring (not shown). Thereby, the flow of ink from the ink tank 46 to the nozzle 44 is controlled.

  The ink temperature adjusting device 48 adjusts the temperature of the ink solution. The ink temperature adjusting device is disposed so as to contact the ink supply tube 47 and adjusts the temperature of the ink solution by heating the ink. Since the viscosity of the ink solution is reduced by heating, it is easy to eject from the nozzle 44.

  The first head joint 41 a is provided with an infrared lamp 54 on the side surface opposite to the ink tank 46. The infrared lamp 54 irradiates infrared rays and dries and fires the ink at the repair location on the glass substrate 12. The infrared lamp 54 is fixed with an inclination so that the irradiated optical path of the infrared ray does not overlap the optical path of the radiation thermometer 39. The focal position of the infrared ray irradiated from the infrared lamp 54 is on a straight line at a portion where the plane formed by the glass substrate surface at the time of ink ejection and the ZY plane passing through the nozzle position intersect.

  A heat insulating plate 53 is disposed between the first head joint 41 a and the infrared lamp 54. That is, the infrared lamp 54 is attached to the first head joint 41 a via the heat insulating plate 53. The heat insulating plate 53 prevents heat generated from the infrared lamp 54 from being transmitted to the nozzle 44. Accordingly, the heat generated by the infrared lamp 54 does not affect the landing accuracy of the ink ejected from the nozzle 44. The heat insulating plate 53 has a structure in which a copper plate with high thermal conductivity on the infrared lamp 54 side and a glass plate with low thermal conductivity on the nozzle 44 side are bonded together. Most of the heat from the infrared lamp 54 toward the nozzle 44 is transmitted to the copper plate in the surface direction and is radiated from above the heat insulating plate 53.

  A position detection sensor (position detection means) 51 is attached to the first head joint 41a. The position detection sensor 51 is attached to the surface of the first head joint 41a opposite to the inkjet head 43. That is, the position detection sensor 51 is integrally attached to the inkjet head 43 via the first head joint 41a.

  Further, the position detection sensor 51 includes a light emitting unit (light emitting unit) 51a and a light receiving unit (light receiving unit) 51b on a bottom surface portion (a portion of the surface facing the glass substrate 13 and the cap unit 60). As the light emitting unit 51a, for example, a light emitting diode can be used, and as the light receiving unit 51b, for example, a phototransistor can be used.

  The light emitted from the light emitting unit 51a is reflected by the reflection target surface and enters the light receiving unit 51b. The position detection sensor 51 can detect the position of the reflection target surface based on the amount of reflected light received by the light receiving unit 51b. For example, when the reflection target surface is on the near side, the light emitted from the light emitting unit 51a passes through the optical path 56a and enters the light receiving unit 51b. When the reflection target surface is on the far side, the light emitted from the light emitting unit 51a enters the light receiving unit 51b through the optical path 56b. In the following, the difference in distance (height direction distance) between the position of the reflection target surface when the reflection target surface is on the near side and the position of the reflection target surface when the reflection target surface is on the far side is shown in the operating range. Called W1.

  The bottom plate 65 is fixed to the second back plate 32. The bottom plate 65 and the second back plate 43 are substantially perpendicular to each other. Further, the bottom plate 65 and the second back plate 32 are connected by a bottom plate joint 66. Thereby, fixation with the baseplate 65 and the 2nd backplate 32 can be performed reliably. On the bottom plate, a capping box 61, a cap unit 60, a discharge confirmation sensor light emitting unit 63a, a discharge confirmation sensor light receiving unit 63b, a capping cleaning mechanism (not shown), and the like are disposed.

  The capping box 61 has a tank for storing waste liquid therein, and is disposed on the bottom plate 65. A cap unit 60 is mounted on the capping box 61. The cap unit 60 is provided with a cap member and the like for protecting the nozzle 44 when the ink jet unit 42 is not operating. The detailed configuration of the cap unit 60 will be described later.

  The ejection confirmation sensor light emitting unit 63a and the ejection confirmation sensor light receiving unit 63b are for confirming the ejection of ink from the nozzles 44 in the inkjet unit. The discharge confirmation sensor light-emitting part 63a and the discharge confirmation sensor light-receiving part 63b are both arranged on the capping box 61, and are arranged to face the position sandwiching the cap unit 60. The light emitted from the discharge confirmation sensor light emitting part 63a is received by the discharge confirmation sensor light receiving part 63b, and the ink discharge is confirmed by the change in the intensity of the received light.

  Here, the cap unit 60 will be specifically described with reference to FIGS. 6 and 7. FIG. 6 is a perspective view illustrating a schematic configuration of the cap unit 60. FIG. 7 is a perspective view showing a schematic configuration in a state where the cap unit 60 is disassembled.

  As shown in FIGS. 6 and 7, the cap unit 60 includes a cap rubber 83, a cap base 81, a cap rubber fixing member 86, a wiping blade 88, and a reflector unit 90.

  The cap rubber 83 is a cap member for protecting the nozzle 44. The cap rubber 83 is placed on the cap base 81 and is fixed to the cap base 81 with screws while being pressed by the cap rubber fixing member 86.

  The cap rubber 83 has a cap lip 85 and an outer wall 84. The cap lip 85 is in contact with an ink discharge port portion (hereinafter referred to as a nozzle surface) of the nozzle 44 when protecting the nozzle 44, and has a shape in which the protruding portion is annular. . When the annular projecting portion contacts the outer peripheral side of the nozzle surface, the nozzle surface can be sealed. Thereby, it can prevent that the nozzle 44 dries. In addition, protecting the nozzle 44 with the cap rubber 83 (sealing state) is hereinafter also referred to as “capping”.

  The outer wall 84 is an enclosure for preventing ink adhering to the nozzle 44 from being scattered outside the cap rubber 83 during the operation of capping the nozzle 44 with the cap rubber 83. For this reason, the outer wall 84 is integrally formed so as to surround the cap lips 85.

  The wiping blade 88 removes ink adhering to the nozzle surface by utilizing the lyophilic / liquid repellency difference between the wiping blade 88 and the nozzle surface when the nozzle surface is separated from the cap rubber 83. is there. The wiping blade 88 is made of an elastic member, and for example, a leaf spring is used.

  In the present embodiment, the cap rubber 83 is formed using perfluoro rubber having chemical resistance against the ink solvent. Perfluoro rubber is a kind of fluoro rubber, and is a material having a very high chemical resistance although it is a material having a small amount of elastic deformation as compared with a silicon rubber used for a conventional cap member. However, the material of the cap rubber 83 is not limited to perfluoro rubber, and any material having high chemical resistance may be used. As described above, any material having high chemical resistance can be used even if the amount of elastic deformation is smaller than that of silicon rubber.

  The reflector unit 90 is placed on the cap base 81 and is fixed to the cap base 81 with screws. The reflector unit 90 is used for positioning the nozzle 44 in the height direction when the cap rubber 83 is capped on the nozzle 44. FIG. 8 is a perspective view showing a schematic configuration in a state where the reflector unit 90 is disassembled.

  As shown in FIG. 8, the reflecting plate unit 90 includes a reflecting plate (reflecting means) 93, a reflecting plate base 91, a holding plate 92, screws 94 and 95, and pins 96. The reflecting plate 93 is placed on the reflecting plate base 91 and is fixed to the reflecting plate base 91 with screws 95 while being pressed by the holding plate 92. The reflecting plate 93 has a trapezoidal shape, and is arranged so that the trapezoidal hypotenuse contacts the two pins 96 provided on the reflecting plate base 91. Thereby, the horizontal position of the reflecting plate 93 is fixed.

  The reflector 93 serves as a reflection target surface when determining the height position during capping. For this reason, the reflecting plate unit 90 is closer to the second back plate 32 than the cap rubber 83, and when the nozzle 44 is capped, the reflecting plate 93 is placed on the optical axis of the light emitted from the position detection sensor 51. Is placed at a position where In addition, it is preferable to arrange the reflecting plate 93 at a position where the distance from the nozzle surface during capping to the surface of the reflecting plate 93 is the same as the distance from the nozzle surface during ink ejection to the glass substrate 13. In this case, the position detection sensor 51 can detect the glass substrate 13 surface during ink ejection and the reflecting plate 93 surface during capping at substantially the same height position.

  The reflection plate 93 may be any plate that can detect the position by the position detection sensor 51. However, in order to perform positioning more reliably, it is preferable that the light reflectance of the reflection plate 93 to be used is the same as the light reflectance of the substrate on which ink is ejected. In this case, a reflector 93 made of the same material as the substrate on which ink is ejected may be used. For example, when ink is ejected onto a glass substrate, a plate made of glass having the same composition as the glass of the glass substrate can be used as the reflecting plate 93. Note that “the same light reflectance” means that the light reflectance of the reflecting plate 93 is exactly the same as the light reflectance of the substrate on which the ink is ejected, When the reflectance is a value close to the reflectance of light on the substrate on which ink is ejected, compared to the reflectance of light on the surface of the cap rubber 83, the surface of the cap base 81, or the surface of the cap rubber fixing member 86, Alternatively, it means a case where the difference between the light reflectance of the reflecting plate 93 and the light reflectance of the substrate on which ink is ejected is within 10%.

  Here, the relative positional relationship between the nozzle 44 and the cap rubber 83 in a state where the cap rubber 83 is capped on the nozzle 44 will be described with reference to FIG. FIG. 1 is a cross-sectional view showing a schematic configuration of the nozzle 44 and the cap unit 60 during capping. In FIG. 1, a staircase cross-sectional view is shown for easy understanding.

  As shown in FIG. 1, the nozzle surface is in contact with the cap lips 85 during capping. The height position of the nozzle surface in this case is defined as a point 105. In addition, a leaf spring-like wiping blade 88 is disposed in a close proximity to the nozzle surface. For this reason, the gap between the nozzle surface and the wiping blade 88 is filled with ink. Thereby, it can prevent that a nozzle surface dries.

  Further, when detecting the position of the reflector 93 during capping, the light emitted from the position detection sensor 51 is reflected by the reflector 93. In this case, the height position of the surface of the reflecting plate 93 is a point 104. The difference in height position between the above points 105 and 104 is small and substantially coincides with the ink flight distance from the nozzle 44 to the glass substrate 13 during ink ejection. For this reason, as will be described later, the distance from the nozzle surface to the surface of the glass substrate 13 at the time of ink ejection is substantially the same as the distance from the nozzle surface to the surface of the reflector at the time of capping. That is, the relative positional relationship between the surface of the glass substrate 13 during ink ejection and the surface of the reflecting plate 93 during capping is substantially the same.

  Next, a mechanism for positioning the nozzle surface during ink ejection and capping will be described with reference to FIG. FIG. 9A is a rear view showing a schematic configuration of a main part of the repair device 1 at the time of ink ejection. FIG. 9B is a rear view showing a schematic configuration of a main part of the repair device 1 at the time of capping. Here, the distance from the surface of the glass substrate 13 to the surface of the reflection plate 93 is W2. As shown in FIGS. 9A and 9B, it can be seen that W2 is clearly larger than the operating range W1 of the position detection sensor 51.

  As shown in FIGS. 9A and 9B, the ink jet unit 42 moves to a position close to the glass substrate 13 when ink is ejected, and moves to a position close to the cap unit 60 when capping. Therefore, as shown in FIG. 9A, when ink is ejected, the height position of the surface of the glass substrate 13 is within the operating range W1 of the position detection sensor 51, and the reflection attached to the cap unit 60. The height position of the surface of the plate 93 is not within the operating range W1. On the other hand, as shown in FIG. 9B, at the time of capping, the height position of the surface of the reflector 93 is within the operating range W1, but the height position of the surface of the glass substrate 13 is within the operating range W1. Absent.

  That is, in both cases of ink ejection and capping, neither the glass substrate 13 nor the reflection plate 93 exists in the operating range W1 of the position detection sensor 51, and only one of them exists. Will be. Therefore, the position detection sensor 51 detects the height position of the surface of the glass substrate 13 when ink is ejected, and detects the height position of the surface of the reflector 93 when capping.

  In both cases of ink ejection and capping, the inkjet unit 42 is moved by moving the X stage 35, the Y stage 37, and the Z stage 33. In particular, the position adjustment of the inkjet unit 42 in the height direction is performed by moving the Z stage 33.

  In order to more reliably adjust the height position, it is preferable to first move the X stage 35 and the Y stage 37 to a predetermined position and then move the Z stage 33. Therefore, in the present embodiment, a case will be described in which the height position is adjusted by moving the Z stage 33 in a state where the inkjet unit 42 is moved to a predetermined position on the XY plane.

  The Z stage 33 moves a certain amount based on the signal sent from the control unit 71. Thereby, the rough height position of the nozzle 44 can be determined. This movement can be performed using a driving device such as a motor.

  At the time of ink ejection, the inkjet unit 42 ejects ink onto the glass substrate 13. For this reason, the inkjet unit 42 moves to a position where the nozzle 44 approaches the glass substrate 13. When the substrate is a large glass substrate 13, the entire glass substrate 13 often swells, and the distance between the nozzle surface and the glass substrate 13 is not necessarily constant.

  For this reason, the position detection sensor 51 is used to detect the position of the surface of the glass substrate 13. The position detection sensor 51 irradiates the glass substrate 13 with light from the light emitting unit 51a, and the reflected light reflected by the glass substrate 13 is received by the light receiving unit 51b. The position detection sensor 51 detects the position of the glass substrate 13 based on the amount of reflected light. Then, the detection result is sent to the control unit 71.

  When detecting the position of the glass substrate 13 by irradiating the glass substrate 13 with light, the position detection sensor 51 transmits the light reflected on the surface of the glass substrate 13 and the glass substrate 13 and transmits the glass substrate 13. In some cases, the light reflected by the substrate holder 12 underneath is received. In this case, the position detection sensor 51 detects the peak of the light quantity related to the two reflected lights, that is, the reflected light from the glass substrate 13 and the reflected light from the substrate holder 12.

  At this time, the amount of reflected light from the substrate holder 12 may be larger than the amount of reflected light from the glass substrate 13. In this case, since the peak of the reflected light from the glass substrate 13 is the second largest peak, the position detection sensor 51 determines the accurate position of the glass substrate 13 based on the light quantity of the second largest peak. To detect. That is, the position detection sensor 51 does not simply detect the position of the glass substrate 13 based on the light amount of the reflected light, but determines an appropriate peak from the distribution of the reflected light amount, and based on the light amount of this peak, the glass substrate 13. Is set to detect the position of.

  The control unit 71 generates a correction signal based on the sent detection result and sends it to the Z stage 33. The Z stage 33 moves by a certain amount based on the correction signal sent from the control unit 71. Thereby, the distance of a nozzle surface and the glass substrate 13 surface can be kept constant. As a result, it is possible to avoid deterioration of the ink landing accuracy on the surface of the glass substrate 13.

  Even during capping, fine adjustment of the height position of the nozzle 44 is performed in the same manner as during ink ejection. That is, first, the inkjet unit 42 moves to a position approaching the cap unit 60. Then, the position of the reflector 93 is detected using the position detection sensor 51. The position detection in this case is also performed in the same manner as described above. Specifically, light is emitted from the light emitting unit 51a of the position detection sensor 51 to the reflecting plate 93, and the reflected light reflected by the reflecting plate 93 is received by the light receiving unit 51b. The position detection sensor 51 detects the position of the reflecting plate 93 based on the amount of the reflected light.

  Then, the detection result is sent to the control unit 71. The control unit 71 generates a signal for moving the Z stage 33 based on the sent detection result, and sends the signal to the Z stage 33. The Z stage 33 moves a certain amount based on the signal sent from the control unit 71. In this case, the Z stage 33 is controlled to stop when the nozzle surface descends from the upper side of the cap rubber 83 and comes into contact with the cap lips 85.

  That is, at the time of capping, the position detection sensor 51 detects the position of the reflecting plate 93 to detect the position of the cap lips 85. Then, by lowering the ink jet unit 42 by an amount corresponding to the detected position of the cap lip 85, the nozzle surface is moved to an optimum position. Thereby, capping of the nozzle 44 can be performed more reliably and accurately, and drying of the nozzle surface can be prevented.

  When the motor for driving the Z stage 33 is a stepping motor, the height position of the Z stage 33 recognized by the control unit 71 and the actual height of the Z stage 33 when a step-out occurs. The position may be different. In this case, if the nozzle 44 is capped by lowering the Z stage 33 by a certain amount only once, after the step-out occurs, the nozzle surface is pressed more than necessary against the cap lip 85. There is. Since the material of the cap rubber 83 has a small amount of elastic deformation as described above, the nozzle surface may be damaged in this case.

  Note that “step-out” is a phenomenon in which the stepping motor cannot follow the pulse signal input to the motor driver that controls the driving of the stepping motor. For example, the movement distance of the Z stage 33 moved by the stepping motor becomes “+29 mm from the origin” even though the signal “Move the Z stage 33 +30 mm from the origin” is transmitted from the motor driver. That is.

  For this reason, when capping, it is preferable to lower the inkjet unit 42 stepwise. The stepwise lowering of the ink jet unit 42 means, for example, that the lowering of the Z stage 33 is temporarily stopped when the nozzle surface moves to a position in front of the cap lip 85 and the position of the Z stage 33 is detected after the position is detected again. It will be lowered. Thereby, even if a step-out occurs, the nozzle surface is not pressed against the cap lips 85 more than necessary, and damage to the nozzle surface can be prevented.

  The position at which the lowering of the inkjet unit 42 is temporarily stopped can be, for example, a position that is approximately ¼ of the operating range W1 above the point where the nozzle surface contacts the cap lips 85. The height position where the nozzle surface comes into contact with the cap lips 85 is a point 105, and the nozzle surface and the cap lips 85 are not in contact when the Z stage 33 is temporarily stopped.

  The point 104 that is the height position of the surface of the reflector 93 and the point 105 are substantially at the same height position, although the height differs by the ink flying distance. For this reason, even if the nozzle surface is at a position higher than the point 105 by about 1/4 of the operating range W1, the surface of the reflector 93 is within the operating range W1. Therefore, the position detection sensor 51 can detect the height position of the surface of the reflecting plate 93.

  After the distance to the surface of the reflector 93 is detected again, the detection result is sent to the control unit 71. The control unit 71 again generates a correction signal for performing fine position adjustment and sends it to the Z stage 33. Then, the Z stage 33 moves (lowers) by an amount based on the correction signal. Thereby, the distance between the nozzle surface and the cap rubber 83 can be kept constant, and the nozzle surface can be brought into contact with the cap lips 85 more reliably. As a result, the risk of damage to the nozzle surface can be avoided.

  In addition, although the cap base 81 and the reflector base 91 exist between the reflecting plate 93 and the cap rubber 83, they are all made of an inelastic member, and the X stage 35, the Y stage 37, and the Z stage 33 The relative position between the reflecting plate 93 and the cap rubber 83 does not change due to movement or the like.

  In the above embodiment, the position detection sensor using light reflection is used. However, the present invention is not limited to this, and any position detection sensor can be used as long as it can detect the position of the cap unit. Even such a position detection sensor can be used.

  In particular, when a position detection sensor that uses light reflection is used and a reflector is used for the cap unit, the light quantity distribution detected during positioning during capping is the light quantity detected during positioning during ink ejection. It becomes almost the same as the distribution. For this reason, in the positioning sensor, the distance from the object determined from the detected light quantity distribution is the same between capping and ink application, and therefore positioning in each case is accurately and safely performed. Can be done.

  The present invention includes a head for ejecting liquid droplets, a capping mechanism for preventing nozzle drying when the head is not used, and a moving means for reciprocating the head between a position for ejecting the recording surface and a position for capping. In the inkjet device having a displacement sensor that is mounted integrally with the head and measures the distance to the recording surface, and the position at which the head ejects droplets onto the recording surface is adjusted to the zero point position of the displacement sensor In addition, a detection reflector having substantially the same reflectivity as the recording surface in the capped state is mounted so that it comes to the zero point position of the displacement sensor, and the recording surface is attached when discharging, and the detection reflector is attached when capping. It can also be expressed as an ink jet device that can be detected at substantially the same height by a displacement sensor. In this ink jet apparatus, the detection reflection plate may be the same as the recording surface.

  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 changed within the scope of the claims are also included in the technical scope of the present invention.

  As described above, by using the ink jet recording apparatus according to the present invention, even when the ink made of various materials is used and the cap member made of a material having a small elastic deformation amount is used, the ink is not ejected. Ink ejection members such as nozzles can be safely protected. Therefore, the ink jet recording apparatus of the present invention can be particularly suitably used for apparatuses for forming various images such as substrate circuit production as well as paper surface printing. Therefore, the present invention can be suitably used in an industrial field for manufacturing various electronic / electrical devices and parts thereof, including the field related to an ink jet recording apparatus.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross-sectional view illustrating a schematic configuration of a nozzle and a cap unit according to an embodiment of the present invention. 1 is a perspective view illustrating a schematic configuration of a repair device according to an embodiment of the present invention. 1 is a perspective view illustrating a schematic configuration of an ink discharge unit according to an embodiment of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 illustrates an embodiment of the present invention, and is a perspective view illustrating a schematic configuration of an inkjet unit, a cap unit, and a peripheral portion thereof. 1 is a perspective view illustrating a schematic configuration of an ink jet unit according to an embodiment of the present invention. 1 is a perspective view illustrating a schematic configuration of a cap unit according to an embodiment of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 illustrates an embodiment of the present invention, and is a perspective view illustrating a schematic configuration in a state where a cap unit is disassembled. 1, showing an embodiment of the present invention, is a perspective view showing a schematic configuration in a state where a reflector unit is disassembled. FIG. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 illustrates an embodiment of the present invention, in which (a) is a rear view illustrating a schematic configuration of a main part of a repair device during ink ejection, and (b) is an overview of a main part of the repair device during capping. It is a rear view which shows a structure.

Explanation of symbols

13 Glass substrate (recording medium)
31 Ink discharge unit (inkjet recording device)
33 Z stage (moving means)
35 X stage (moving means)
37 Y stage (moving means)
42 Inkjet unit (ink discharge means)
51 Position detection sensor (position detection means)
51a Light emitting part (light emitting means)
51b Light receiving part (light receiving means)
60 Cap unit (protection means)
93 Reflector (reflecting means)

Claims (5)

In an ink jet recording apparatus including an ink discharge unit that discharges ink to a recording medium and a protection unit that protects the ink discharge unit when ink is not discharged,
A position detecting means for detecting the position of the recording medium when ink is ejected, and for detecting the position of the protection means when ink is not ejected;
An ink jet recording apparatus comprising: a moving unit that moves the ink discharging unit based on a detection result of the position detecting unit. The protection means includes a reflection means for reflecting light,
2. The position detecting means comprises: a light emitting means for emitting light to the recording medium or the reflecting means; and a light receiving means for receiving the reflected light from the recording medium or the reflecting means. The ink jet recording apparatus described.   3. The ink jet recording apparatus according to claim 2, wherein the light reflectance of the reflecting means is the same as the light reflectance of the recording medium.   4. The ink jet recording apparatus according to claim 2, wherein the reflecting means is made of the same material as that of the recording medium.   The reflection means is disposed at a position where the distance between the ink ejection means and the reflection means in a state where the ink ejection means is protected by the protection means is the same as the distance between the ink ejection means and the recording medium during ink ejection. The ink jet recording apparatus according to claim 2, wherein the ink jet recording apparatus is provided.

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