JP6090647B2 - Alignment apparatus and alignment method - Google Patents

Description

  The present invention relates to an alignment apparatus and an alignment method for positioning a frame member of a droplet discharge head and a nozzle plate when the nozzle plate is assembled to the frame member of the droplet discharge head.

  The following systems are known as image forming apparatuses such as printers, facsimiles, copiers, plotters, and complex machines of these. For example, an ink jet recording apparatus or the like is known as an image forming apparatus of a liquid discharge recording method using a recording head composed of a droplet discharge head that discharges ink droplets onto a medium while conveying the medium. The medium here is also referred to as “paper”, but the material is not limited, and a recording medium, a recording medium, a transfer material, a recording paper, and the like are also used synonymously. The image forming apparatus means an apparatus for forming an image by discharging a liquid onto a medium such as paper, thread, fiber, fabric, leather, metal, plastic, glass, wood, ceramics. The image formation is not only giving an image having a meaning such as a character or a figure to the medium but also giving an image having no meaning such as a pattern to the medium (simply ejecting a droplet). Also means. The ink is not limited to so-called ink, and is not particularly limited as long as it becomes liquid when ejected. For example, the ink is a generic term for liquids including DNA samples, resists, pattern materials, and the like. Use. Furthermore, the image is not limited to a flat image, and includes an image given to a three-dimensionally formed image and an image formed by three-dimensionally modeling a solid itself.

  In the ink jet recording apparatus, it is necessary to land the landing position on the paper of the ink ejected from the nozzle of the ink jet head at the target position. Therefore, based on the attachment position reference | standard provided in the frame member (head frame) of the inkjet head, a nozzle plate is positioned to the frame member of an inkjet head, and it mutually joins.

  As an alignment apparatus that positions and joins a nozzle plate to a frame member when the nozzle plate is assembled and joined to a frame member of an inkjet head, there is an apparatus known in Patent Document 1. In the alignment apparatus of Patent Document 1, a reference mark serving as a positioning reference is provided on a holding means (head frame installation portion) that holds a frame member of an inkjet head at a target position. The reference mark is provided with a through hole. The nozzle plate is positioned on the frame member of the inkjet head by positioning the alignment mark (first mark) provided on the nozzle plate and the reference mark through the through hole. In order to perform this positioning, a bifocal microscope is used.

  This bifocal microscope includes two beam splitters, two mirrors, two focus lenses, and one objective lens to form two optical paths (optical systems) having different focal lengths. . In addition to the optical path composed of these optical members, the alignment apparatus includes a light source and an imaging means. Then, two optical paths are formed, and the focal lengths of the first focal lens provided on one optical path and the focal lengths of the second focal lens provided on the other optical path are made different from each other, whereby different focal points are obtained. Two optical paths having a distance are formed. In the alignment apparatus of Patent Document 1 using this bifocal microscope, the light from the location of the reference mark forms an image on the imaging means via each optical member in the reverse order of the forward path in one optical system. . Then, the light from the position of the alignment mark forms an image on the imaging means via each optical member in the reverse order of the forward path in the other optical system. By these, the location of the reference mark and the location of the alignment mark are imaged. Then, the frame member or nozzle plate of the inkjet head is relatively moved so that the center of the reference mark and the center of the alignment mark coincide with each other in the same field of view of the image of the reference mark and the alignment mark. Then, the nozzle plate is positioned on the frame member of the inkjet head and joined together.

  However, in the alignment apparatus of Patent Document 1, the reference mark portion and the alignment mark portion which are at different positions in the same direction are imaged by the imaging means via the bifocal microscope. For this reason, two optical paths having different focal lengths are required between the imaging means and one objective lens, and the number of optical components is increased.

  The present invention has been made in view of the above problems, and an object thereof is to provide an alignment apparatus and an alignment method capable of positioning a nozzle plate on the head frame of a droplet discharge head with relatively few optical components. .

In order to achieve the above object, according to the first aspect of the present invention, when the nozzle plate is assembled to the head frame of the droplet discharge head, the first mark corresponding to the nozzle plate is based on an image captured by an imaging unit. in the alignment device for positioning of the head frame and said nozzle plate, and the head frame installed portion to which the head frame is mounted, the second mark and before SL that to said image pickup means provided in a direction different from that of the head frame installed portion an optical system consisting of a single half mirror Ru is imaged and the first mark in the same image pickup means corresponding to the nozzle plate on the head frame installed in the head frame installed portion, and the first mark on the same field first Adjustment means for adjusting the position by moving the head frame relative to the nozzle plate so that the two marks coincide with each other The is characterized in that it comprises.

In the alignment apparatus of the present invention, the second mark is set to coincide with the first mark of the nozzle plate assembled to the already aligned head frame on the same field of view. Then, alignment is performed by adjusting the position of the nozzle plate so that the first mark and the second mark are relatively coincident with each other on the image picked up by the image pickup means. In this alignment apparatus, since the location of the head frame installation portion and the location of the second mark are in different directions with respect to the imaging means, the first mark and the second mark of the nozzle plate are imaged on the same imaging means. Therefore, the directions of the optical paths on the objective side in the optical system composed of one half mirror are different from each other. Unlike the conventional alignment apparatus using a bifocal microscope, the optical system for combining two marks with different focal lengths toward one objective lens is different from the direction of the optical path on the objective side in the same direction. The member can be omitted. Therefore, a unique effect is obtained that the nozzle plate can be positioned on the head frame of the droplet discharge head with relatively few optical components.

It is a principal part expanded sectional view of the direction between channels of the discharge part of the inkjet head applied to the electrical pressure conversion means. It is a top view which shows the Example of the external shape of a frame member. It is an exploded view of the inkjet head of a present Example. It is the schematic which shows the example of attachment to a serial printer. 2 is a schematic diagram illustrating an example of attachment to an MFP body. FIG. It is a perspective view showing the whole alignment device concerning this embodiment. It is a figure which shows the mode of fixation of the frame member which concerns on this embodiment, a glass chart, and a half mirror. It is sectional drawing which shows the structure of a joint surface copying mechanism. It is a perspective view which shows the glass chart provided with the reference mark. It is a perspective view which shows the master workpiece | work provided with the adjustment target mark. It is a perspective view which shows the layout of a detection optical means. It is a schematic side view which shows the optical path of the detection optical system of a detection optical means. It is a figure which shows the detection image with two CCD cameras. It is a flowchart which shows the operation | movement from alignment to joining. It is a figure which shows the position of the adhesive agent apply | coated to the frame member.

An example of an inkjet head positioned by the alignment apparatus according to the embodiment of the present invention will be described.
FIG. 1 is an enlarged cross-sectional view of a main part in a channel-to-channel direction of an ejection part of an ink jet head applied to an electric pressure converting means. In the figure, the ink jet head discharge section includes a frame member 1, a diaphragm 2, a flow path plate 3, a nozzle plate 4, a laminated piezoelectric element 5, and a PZT base 6. The frame member 1 is a member in which an engraving that forms the ink supply port 16 and the common liquid chamber 8 is formed. The diaphragm 2 includes a convex portion 13, a diaphragm portion 14, and an ink inflow port 15. The flow path plate 3 is formed with an engraving that becomes the pressurized liquid chamber 9 and the fluid resistance portion 10 and a communication hole 12 that communicates with the nozzle 11. A nozzle 11 is formed on the nozzle plate 4. The laminated piezoelectric element 5 is joined to the diaphragm 2 via an adhesive layer. The PZT base 6 fixes the laminated piezoelectric element 5.

  The PZT base 6 is made of a barium titanate ceramic, and the laminated piezoelectric elements 5 are arranged in two rows and joined. The laminated piezoelectric element 5 is composed of a lead zirconate titanate (PZT) piezoelectric layer (not shown) having a thickness of 10 to 50 [μm / layer], and silver / palladium having a thickness of several μm / layer (μm / layer). Internal electrode layers (not shown) made of AgPd) are alternately stacked. An internal electrode layer (not shown) is connected to an external electrode (not shown) at both ends. The laminated piezoelectric element 5 is divided on comb teeth by half-cut dicing and used as a drive unit and a support unit (non-drive unit) one by one. The outside of the external electrode (not shown) is limited by machining such as notches so as to be divided by half-cut dicing, and these become a plurality of individual electrodes (not shown). The other is conductive without being divided by dicing, and becomes a common electrode. An FPC 7 is soldered to an individual electrode (not shown) of the drive unit. In addition, the common electrode is provided with an electrode layer at the end of the laminated piezoelectric element 5 and is wound around and joined to the Gnd electrode 5-1 of the FPC 7. A driver IC (not shown) is mounted on the FPC 7 to control application of a drive voltage to the drive unit.

  The diaphragm 2 has a thin film diaphragm portion 14, an island-shaped convex portion (island portion) 13, a thick film portion including a beam joined to a support portion (not shown), and an opening serving as an ink inlet 15. Two layers of Ni plating films are formed by electroforming. The island-shaped convex part 13 is joined to the laminated piezoelectric element 5 that becomes a driving part formed in the center part of the diaphragm part 14. The thickness of the diaphragm part 14 is 3 [μm], and the width is 35 [μm] (one side). The island-shaped convex portion 13 of the diaphragm 2 and the movable portion 5-2 of the laminated piezoelectric element 5, and the coupling of the diaphragm 2 and the frame member 1 will be described in detail later, but the adhesive layer including the gap material is patterned. And glued.

  Furthermore, the flow path plate 3 was formed by using a silicon single crystal substrate and patterning a pressurizing liquid chamber 9, a carving to be a fluid resistance portion 10, and a through hole to be a communication hole 12 at a position relative to the nozzle 11 by an etching method. Specifically, it can be formed by anisotropic etching using an alkaline etching solution such as an aqueous potassium hydroxide solution (KOH). The portion left by etching becomes a partition wall of the pressurized liquid chamber 9. Further, in this head, a portion for reducing the etching width was provided, and this was used as the fluid resistance portion 10.

  The nozzle plate 4 is formed of a metal material, for example, an Ni plating film formed by an electroforming method, and has a large number of nozzles 11 which are fine discharge ports for causing ink droplets to fly. The inner shape (inner shape) of the nozzle 11 is formed in a horn shape, but may be a substantially cylindrical shape or a substantially frustum shape. The diameter of the nozzle 11 is about 15 to 30 [μm] on the ink droplet outlet side. The nozzle pitch of each row was 150 or 300 [dpi]. The ink ejection surface (nozzle surface side) of the nozzle plate 4 is provided with a water repellent treatment layer (not shown) subjected to a water repellent surface treatment (not shown). Ink physical properties such as PTFE-Ni eutectoid plating, fluororesin electrodeposition coating, vapor-deposited fluororesin (for example, fluorinated pitch), and baking after solvent coating of silicon resin / fluorine resin A water repellent film selected according to the above is provided. In addition, the ink droplet shape and flight characteristics are stabilized so that high-quality image quality can be obtained.

  The frame member that forms the engraving that becomes the ink supply port 16 and the common liquid chamber 8 is made by resin molding. The periphery of the ink inlet 15 of the vibration plate 2 is sealed and bonded with an adhesive applied to the frame member 1 without a gap. In this frame member 1, a common liquid chamber 8 for supplying ink to each pressurized liquid chamber 9 is formed. From the common liquid chamber 8 to the ink inlet 15 formed in the diaphragm 2 and upstream of the fluid resistance portion 10. The ink liquid is supplied to the pressurized liquid chamber 9 through the formed flow path and the fluid resistance portion 10. The frame member 1 is also formed with an ink supply port 16 for supplying ink liquid from the outside to the common liquid chamber 8. Further, the common liquid chamber 8 is formed in a rectangular shape with a planar shape in the direction in which the pressurized liquid chambers 9 are aligned (nozzle alignment direction).

  In the ink jet head configured as described above, a drive waveform (pulse voltage of 10 to 50 [V]) is applied to the drive unit in accordance with the recording signal. A displacement in the stacking direction occurs in the driving unit, the pressurized liquid chamber 9 is pressurized through the diaphragm 2, the pressure is increased, and ink droplets are ejected from the nozzle 11. Thereafter, the ink pressure in the pressurizing liquid chamber 9 decreases with the end of ink droplet ejection, and a negative pressure is generated in the pressurizing liquid chamber 9 due to the inertia of the ink flow and the discharge process of the drive pulse. Move to the process. At this time, the ink supplied from the ink tank flows into the common liquid chamber 8, passes from the common liquid chamber 8 through the ink inlet 15, passes through the fluid resistance portion 10, and is filled into the pressurized liquid chamber 9. The fluid resistance unit 10 has an effect on the attenuation of the residual pressure vibration after ejection, but becomes resistant to refilling (refilling) due to surface tension. By appropriately selecting the fluid resistance unit 10, the balance between the attenuation of the residual pressure and the refill time can be achieved, and the time (drive period) until the transition to the next ink droplet ejection operation can be shortened.

  In the present embodiment, it is preferable that at least a part of the liquid chamber portion, the fluid resistance portion, the vibration plate, and the nozzle member of the ink discharge portion of the ink jet head are formed of a material containing at least one of silicon and nickel. Further, in the present embodiment, the case where a laminated piezoelectric element is used as the drive actuator has been described, but a thin film piezo or the like may be used as the actuator.

Next, the frame member (first component) and the nozzle plate (second component) of the inkjet head that are positioned and joined by the alignment apparatus of the present embodiment will be described.
FIG. 2 is a plan view showing an example of the outer shape of the frame member. The first part is the frame member 1 of FIG. The outer shape of the frame member 1 has three butting portions 21, 22, and 23 serving as position references. One abutting portion 21 in the longitudinal direction (X direction in FIG. 2) and two abutting portions 22 and 23 in the short direction (Y direction) are provided. The abutment portions 21, 22, 23 and the reference pins 27, 28, 29 provided on the attachment base 30 are urged and abutted by the urging springs 24, 25, 26, so that the attachment base of the frame member 1 The position relative to 30 is determined.

  FIG. 3 is an exploded view of the ink jet head of this embodiment. The second component that is positioned and joined by the alignment apparatus of this embodiment is an integrated component 17 with a nozzle plate. As shown in FIG. 3, the integrated component 17 with the nozzle plate is a component in which the nozzle plate 4, the flow path plate 3, the vibration plate 2, the laminated piezoelectric element 5, the PZT base 6, and the FPC 7 are joined with an adhesive or the like in the previous process. is there. More specifically, the joining process, which is the previous process, assembles the integrated component 17 with the nozzle plate by the following process. In the first step, the flow path plate 3 and the diaphragm 2 are bonded and joined. In the second step, the laminated piezoelectric element 5 and the PZT base 6 are bonded and bonded. In the third step, the bonded product of the flow path plate 3 and the diaphragm 2 and the nozzle plate 4 are bonded and bonded. In the fourth step, the FPC 7 is soldered to the joined product of the laminated piezoelectric element 5 and the PZT base 6. In the fifth step, the joined product of the flow path plate 3, the vibration plate 2 and the nozzle plate 4 and the joined product of the laminated piezoelectric element 5, the PZT base 6 and the FPC 7 are adhesively joined.

Next, a description will be given of a method of attaching an ink jet head in which an ink tank or the like is attached to components positioned and joined by the alignment apparatus of the present embodiment to a serial printer or MFP main body.
First, attachment to a serial printer will be described. FIG. 4 is a schematic view showing an example of attachment to a serial printer. In the serial printer, a carriage 233 is slidably held in the main scanning direction by main and sub guide rods 231 and 232 which are guide members horizontally mounted on the left and right side plates 221A and 221B. Then, the main scanning motor (not shown) moves and scans in the direction indicated by the arrow (carriage main scanning direction) via the timing belt. One inkjet head 234 is positioned on the carriage 233 based on the outer shape of the frame, and is fixed with the droplet discharge direction directed toward the paper 242. One ink jet head 234 includes four nozzle rows that eject ink droplets of each color of yellow (Y), cyan (C), magenta (M), and black (K). The ink jet head 234 is supplementarily supplied with ink of each color from the ink cartridge 210 of each color by the supply unit 224 via the supply tube 236 for each color. The sheet 242 is electrostatically attracted and conveyed to a position facing the ink jet head 234 for printing.

  Next, attachment to the MFP main body will be described. FIG. 5 is a schematic view showing an example of attachment to the MFP main body. As shown in the figure, after the urging springs 24, 25, and 26 (thin plate springs in the example of FIG. 5) are urged to the three reference pins 27, 28, and 29, the fixing bolts are applied to each inkjet head. It is fixed with. In this example, twelve inkjet heads 301 are arranged in a staggered manner in two rows in the horizontal direction (longitudinal direction) with respect to one unit base 300. Printing can be performed by moving the recording medium in the vertical direction of FIG. In one MFP, the number of unit bases can be increased as appropriate to increase the number of colors or the number of dots per inch (dpi).

Next, the alignment apparatus of this embodiment will be described.
FIG. 6 is a perspective view showing the entire alignment apparatus according to the present embodiment. The alignment apparatus of this embodiment is an apparatus that joins the frame member 1 and the integrated component 17 with the nozzle plate. FIG. 7 is a diagram showing how the frame member, the glass chart (reference member), and the half mirror according to the present embodiment are fixed. In both figures, the alignment apparatus of the present embodiment includes a pressure stage 36 (load control: for example, electropneumatic actuator drive), a bonding surface copying mechanism 38, an upper suction stage 34, an XYθ stage 37, a lower suction stage 31, and a clamping unit. 32 and 33 and a Z-axis stage 35. Further, reference pins 27, 28 and 29, a half mirror 43, a master work 46, a glass chart 60, and a posture position adjusting means 62 are included. The integrated component 17 with the nozzle plate conveyed from the previous process is vacuum-adsorbed and fixed to the upper suction stage 34 by a vacuum pump at a target position.

A method for fixing the frame member 1 will be described with reference to FIGS. 2 and 7.
The frame member 1 is positioned on the lower suction stage 31 by the clamping means 32 and 33 in two directions of the longitudinal direction (X direction) and the short direction (Y direction). The clamp means 32 is used to press and abut against one reference pin 27 that regulates the position in the X direction. Further, the clamp means 33 is used to press and abut against the two reference pins 28 and 29 that regulate the position in the Y direction. A plunger at the tip R is provided for pressing the clamping means 32 and 33, and a pressing force is applied by this spring force. A cylinder or the like is used for driving the clamping means 32 and 33. After the frame member 1 is positioned at a predetermined position, the frame member 1 is vacuum-sucked and fixed by a vacuum pump (not shown) of the lower suction stage 31.

  The Z-axis stage 35 can be moved up and down while the frame member 1 is vacuum-sucked to the lower suction stage 31. The pressure stage 36 can be moved up and down in a state where the integrated component 17 with the nozzle plate is vacuum-sucked to the upper suction stage 34. The pressure stage 36 includes a pressure actuator 39 that can control the load, a guide mechanism 40, and a pressure table 41. Specifically, the position and load can be controlled by using an electropneumatic actuator as the pressure actuator 39. Using this pressure stage 36, pressure bonding is performed between the frame member 1 and the integrated component 17 with the nozzle plate via an adhesive. At this time, an arbitrary load can be set by load control, but in this embodiment, two loads, a low pressure (for example, 5 [N]) and a main pressure (for example, 60 [N]) are set. Yes.

  The XYθ stage 37 is fastened to the lower side of the Z-axis stage 35. With this XYθ stage 37, the frame member 1 on the Z-axis stage 35 can be aligned at a predetermined position in the plane. A bonding surface copying mechanism 38 is disposed on the lower surface of the pressure table 41, and an upper suction stage 34 is attached to the lower surface of the bonding surface copying mechanism 38 via a block base 42. The integrated part 17 with the nozzle plate is vacuum-sucked.

  FIG. 8 is a cross-sectional view showing the configuration of the joint surface copying mechanism. The joining surface copying mechanism 38 shown in the figure includes a spherical member 76 having a convex spherical surface 75 fixed to the upper surface side of the upper suction stage 34, a receiving bearing member 79 having a concave spherical surface 77 for receiving the spherical member 76, and And a receiving member 78 having a concave spherical surface for receiving the bearing member 79. The spherical member 76 is configured such that its convex spherical surface 75 can freely move along the concave spherical surface 77 of the bearing member 79 via a bearing member 79 having an air floating mechanism. By this movement, when the integral part 17 with the nozzle is brought into contact with the frame member 1, the parallelism between the two automatically matches with the frame member 1 almost completely. The air supply to the concave spherical surface 77 of the bearing member 79 is performed by the compressed air from the air supply port 74 to constitute an air floating mechanism.

  Further, the lock mechanism in the joint surface copying mechanism 38 is configured as follows. That is, the cylinder 70 and the piston 71 accommodated therein are provided over the spherical member 76, the bearing member 79, and the receiving member 78. By supplying air to the lock port 72 of the air cylinder mechanism, the piston 71 is moved upward so that the position and posture of the spherical member 76 are locked to the receiving member 78 via the piston 71. It has become. By supplying air to the free port 73, the piston 71 is moved downward, the lock is released, and the spherical member 76 is freely imitated with respect to the receiving member 78. At this time, the frame member 1 is vacuum sucked and held by vacuum suction by a vacuum pump (not shown) through the vacuum port 82. Similarly, the integrated component 17 with the nozzle plate is vacuum-sucked and held by vacuum suction by a vacuum pump (not shown) through the vacuum port 83. The vacuum port 81 can hold the convex spherical surface 75 of the spherical member 76 and the concave spherical surface 77 of the bearing member 79 by vacuum suction with a vacuum pump (not shown). It is possible to lock with a holding force weaker than the above-described locking mechanism. The locking mechanism by the joint surface copying mechanism 38 may be applied to either the case of using the air cylinder mechanism, the case of using the vacuum suction mechanism, or the case of using both.

  Next, the operation of the copying and holding mechanism will be described. First, the operation of adjusting the parallelism of the lower suction stage 31 and the upper suction stage 34 respectively held by the frame member 1 and the nozzle-equipped integrated component 17 will be described. As shown in FIG. 8, air is supplied to the free port 73 in the joint surface copying mechanism 38 to make the spherical member 76 free with respect to the receiving member 78, and in this state, the second holding means is raised and the second holding means is raised. Press the part against the first part. Then, the joining surface tracing mechanism 38 causes the second component to follow the first component, that is, to make the parallelism between the second component and the first component almost perfectly match. After the copying operation, the spherical member 76 can be temporarily locked to the bearing member 79 in a state where air is supplied to the lock port 72 and the parallelism is adjusted. Since the spherical member 76 sucks and holds the integrated component 17 with the nozzle by the upper suction stage 34, the parallelism between the frame member 1 and the integrated component 17 with the nozzle is adjusted by locking the spherical member 76. Will be maintained.

  The block base 42 has a box shape, and two half mirrors 43a and 43b and a glass chart fixing base 44 are disposed in a non-contact manner inside the block base 42. The block base 42 has a box-shaped side surface provided with a window so that it can be detected by the CCD cameras 50a and 50b as image pickup means so as not to block the view. A through-hole 45 is provided on the lower surface of the block base 42 at the same position as the upper suction stage 34, and the adjustment target marks 47a and 47b or the nozzle alignment marks 18a and 18b of the master work 46 can be detected. ing. The imaging means includes an imaging element such as a CCD or C-MOS.

  The frame member 1 and the integrated component 17 with the nozzle plate are irradiated with UV light from the four UV irradiators 48 at the positions where the UV adhesives at the four corners are crushed by the pressure in a state where the main pressure is applied. It can be cured and temporarily joined. Moreover, the UV irradiator 48 can be moved by the left and right cylinders 49 two by two so that the frame member 1 and the integrated part 17 with the nozzle plate are not hindered.

  As shown in FIG. 7, the glass chart 60 is fixed on the glass chart fixing base 44. The glass chart fixing base 44 is fastened to the lower suction stage 31 via a glass chart connecting block 64, and is moved by the Z-axis stage 35 and the XYθ stage 37 shown in FIG.

  FIG. 9 is a perspective view showing a glass chart provided with a reference mark. This is a structure in which quartz glass is bonded to a SUS substrate, and is made of a reflective chromium film formed by exposing and transferring a mask pattern to quartz glass. In the example of the fiducial mark 61 shown in FIG. 9, there are two fiducial marks 61a and 61b composed of a cross shape with an outer diameter of 500 [μm] and an inner diameter of 490 [μm] and a line width of 5 [μm]. The intervals are arranged with an accuracy within ± 1 [μm]. The arrangement of the glass chart 60 and the adjustment of the posture position are performed using the posture position adjusting means 62. As shown in FIG. 7, the position of the glass chart 60 is fixed by adjusting the positions of left and right, up and down, and front and rear by the six clamp bolts 63 by the posture position adjusting means 62.

  FIG. 10 is a perspective view showing a master work provided with an adjustment target mark. Adjustment target marks 47a and 47b that are adjustment target positions of the nozzle alignment marks 18a and 18b are provided. This is a structure in which quartz glass is bonded to a SUS substrate, and is made of a reflective chromium film formed by exposing and transferring a mask pattern to quartz glass. In the example of the preparation target mark 47 shown in FIG. 10, there are two preparation target marks 47a and 47b having a diameter of 80 [μm], a solid shape and a crosshair, and a line width of the crosshair of 5 [μm]. Are arranged with an accuracy within ± 1 [μm]. This interval has the same dimension as the pitch between the reference marks 61a and 61b. When the master work 46 is used for adjusting the optical axis, the same clamping method as that for clamping the frame member 1 is used.

  The two half mirrors 43a and 43b are fixed to the glass chart fixed base 44 as shown in FIG. For this reason, it moves by the Z-axis stage 35 and the XYθ stage 37. In order not to contact the block base 42 described above, the operation is controlled so that the interlock is effective in each operation so that the Z-axis stage 35, the XYθ stage 37, and the pressure stage 36 do not interfere even if they move. Yes.

  FIG. 11 is a perspective view showing the layout of the detection optical means. The detection optical means 100 and 200 constitute a bifocal detection optical system as will be described later, and join the frame member 1 and the integrated component 17 with the nozzle plate. At this time, the nozzle alignment marks 18a and 18b provided at both ends in the longitudinal direction (X direction) of the nozzle plate 4 and the reference marks 61a and 61b provided at both ends in the longitudinal direction of the glass chart 60, which serve as an adjustment reference for the nozzle alignment mark 18. Is detected. The detection optical means 100 detects the nozzle alignment mark 18a and the reference mark 61a simultaneously by the two detection optical means 100 and 200 arranged at both ends of the nozzle plate 4. The detection optical means 200 detects the nozzle alignment mark 18b and the reference mark 61b simultaneously. Here, the detection optical means 100 and 200 are composed of a CCD camera 50, a coaxial incident illumination 51, and an image processing unit (not shown).

Next, the detection optical system and the optical path of the detection optical means will be described.
In the alignment apparatus of the present embodiment, two detection optical means 100 and 200 are used. Here, the optical path of the detection optical system of the detection optical means 100 will be described with reference to FIG. 12, but the detection optical means 200 is exactly the same. The position of the CCD camera 50 can be adjusted using a manual triaxial stage 53. As shown in FIG. 12, as the adjustment direction of the manual triaxial stage 53, the X direction is the alignment mark pitch direction, the Y direction is the camera depth direction, and the Z direction adjusts the camera height up and down. Direction. A coaxial epi-illumination 51 is incident on the optical axis of the CCD camera 50, and the optical path is branched by the half mirror 43 into two optical paths L 1 and L 2.

  The optical path L1 is an optical path that goes straight through the half mirror 43 as it is, travels and reflects to the glass chart 60 provided with the reference mark 61, passes through the half mirror 43 again, and returns to the CCD camera 50. The optical path L <b> 2 is an optical path that is bent 90 degrees by the half mirror 43, travels and reflects to the master work 46 provided with the adjustment target mark 47, passes through the half mirror 43 again, and returns to the CCD camera 50. The optical path L2 detects the nozzle alignment mark 18 of the nozzle plate 4 instead of the adjustment target mark 47 of the master work 46 at the time of joining. A half mirror 43 is arranged so that the images of the optical paths L1 and L2 are focused by the CCD camera 50, and constitutes a kind of bifocal detection optical system. The CCD camera 50 is provided with a high-magnification (× 6 times) machine vision lens, and the reference mark 61 and the adjustment target mark 47 can be enlarged and detected.

Next, a method for adjusting the optical axes of the optical paths L1 and L2 of the detection optical means in the alignment apparatus according to the present embodiment will be described.
Adjustment of the optical paths L1 and L2 of the detection optical means shown in FIG. 12 is performed by adjusting the positions of the half mirror 43 and the glass chart 60 and fixing them. The positions of the half mirror 43 and the glass chart 60 are adjusted so that the adjustment target mark 47 of the master work 46 and the reference mark 61 of the glass chart 60 are aligned in the image acquired by the CCD camera 50. Thereby, the position of the adjustment target mark 47 of the master work 46 is traced to the position of the reference mark 61 of the glass chart 60. That is, the ideal joining position from the outer shape reference of the frame member 1 in the nozzle alignment mark 18 in the nozzle 11 is the position of the adjustment target mark 47 of the master work 46. Therefore, if the position of the adjustment target mark 47 can be traced to the reference mark of the glass chart 60, the actual frame member 1 and the nozzle plate-equipped integrated component 17 are joined. At that time, the frame member 1 is fixed at a predetermined position by a predetermined clamping means. Thereafter, the nozzle alignment mark 18 of the nozzle plate-integrated component 17 and the reference mark 61 of the glass chart 60 are simultaneously imaged using the detection means 100 and 200 including the above-described bifocal detection optical system. Then, the movement instruction amount is calculated by the image processing unit, and aligned and aligned by the XYθ stage 37, whereby the frame member 1 and the nozzle plate-equipped integrated component 17 can be positioned and joined with high accuracy.

Here, a procedure for aligning the position of the adjustment target mark 47 of the master work 46 and the position of the reference mark of the glass chart 60 will be described below. FIGS. 13A to 13C are diagrams showing detected images by two CCD cameras.
First, the glass chart 60 is arranged at a substantially designed position. The Z-axis stage 35 has a predetermined joining height. Here, the positions of the CCD cameras 50a and 50b are adjusted by the manual triaxial stage 53 so that the detected images of the reference marks 61a and 61b of the glass chart 60 by the optical path L1 are focused at the center of each image. For example, the process is performed as shown in FIG. Next, the master work 46 is clamped and fixed using the same clamping means 32 and 33 with the same outer shape reference as the frame member 1. An image detected by the optical path L2 of the adjustment target marks 47a and 47b of the master work 46 is focused at the center of each image of the CCD cameras 50a and 50b. Then, the height and posture of the adjustment to the glass chart fixing base 44 are adjusted so that the Y-direction positions of the adjustment target marks 47a and 47b of the master work 46 coincide with the Y-direction positions of the reference marks 61a and 61b of the glass chart 60, respectively. adjust. Then, the half mirrors 43a and 43b are fixed. At this time, in order to focus the detection images of the adjustment target marks 47 a and 47 b on the CCD camera 50, the position of the camera Y axis in the depth direction of the CCD cameras 50 a and 50 b is moved using the manual triaxial stage 53. Let

  At the same time, the Y-axis adjustment that is the depth direction of the CCD cameras 50a and 50b adjusts the focus of the reference marks 61a and 61b of the glass chart 60 that is a detection image by the optical path L1. For this reason, the position of the glass chart 60 in the front-rear direction is finely adjusted using the position / posture position adjusting means 62. Thus, for example, the process is performed as shown in FIG. Next, the positions of the images of the reference marks 61a and 61b of the glass chart 60, which are detected images by the optical path L1, and the positions of the adjustment target marks 47a, 47b of the master work 46, which are detected images by the optical path L2, are the center positions. Make sure it fits. Then, the position of the glass chart 60 in the X direction is finely adjusted using the position and orientation adjusting means 62 and fixed. Thus, for example, the process is performed as shown in FIG.

  Next, operations from alignment to bonding will be described. Here, an alignment operation and a bonding operation of the inkjet head 220 to a predetermined position will be described using the alignment apparatus according to the present embodiment. FIG. 14 is a flowchart showing operations from alignment to joining. Note that the Z-axis stage 35 (ST: 10 [mm]) is a stage that repeatedly moves with high positioning accuracy between two positions of an ascending position and a descending position. The pressurization stage 36 (ST: 1 [mm]) has a pressurization position (lowering position) and an escape position (upward position). The position of the pressurizing position is a lowered position where a predetermined joining pressure is applied between the nozzle plate and the frame. The XYθ stage 37 is an automatic stage that performs automatic alignment with respect to a movement command calculated based on the imaging result acquired from the detection optical means 100 and 200. The upper suction stage 34 and the lower suction stage 31 are plates that vacuum-suck a workpiece.

  First, the nozzle discharge side is vacuum-sucked by the upper suction stage 34 with the integrated component 17 with the nozzle plate (step S101). At this time, the Z-axis stage 35 is lowered to the lowered position. Further, the pressure stage 36 is lowered to the pressure position. At this time, since the frame member 1 is not placed on the Z-axis stage 35, there is room in the space for vacuum-sucking the integrated component 17 with the nozzle plate. For this reason, the integrated part 17 with the nozzle plate which has been conveyed can be easily adsorbed to the upper adsorption stage 34. Then, the Z-axis stage 35 is raised to the raised position. Further, the pressure stage 36 is kept lowered to the pressure position. At this position, it is confirmed whether the nozzle alignment marks 18a and 18b are captured within the angle of view of the CCD cameras 50a and 50b (step S101). If it is within the angle of view, the process proceeds to the next step S103. Then, as shown in FIG. 15 showing the position of the adhesive applied to the frame member, the main adhesive for bonding and the four corners on the upper surface are joined to the joint surface with the integral part 17 with the nozzle plate on the entire upper surface 91 of the frame member 1 A pre-bonding UV adhesive is preliminarily applied to the pressure relief portion 92 provided on the surface. The Z-axis stage 35 is lowered to the lowered position, and the pressure stage 36 is raised to the raised position. The frame member 1 to which the adhesive is applied is abutted and clamped to the reference pins 27, 28, 29 using the clamping means 32, 33 of FIG. 7, and is vacuum-sucked to the lower suction stage 31 at that position (step S103).

  Next, after raising the Z-axis stage 35 to the raised position, the lock of the joining surface copying mechanism 38 is released, and the pressure stage 36 is slowly lowered to the pressure position. The pressure stage 36 performs load control and lowers the pressure stage 36 to a position where a weak pressure (about 5 N) acts as a bonding load between the integrated component 17 with the nozzle plate and the frame member 1. In this state, the joint surface copying mechanism 38 is locked, and the XYθ stage 37 is used to image the reference marks 61a and 61b and the nozzle alignment marks 18a and 18b of the glass chart 60 with the CCD cameras 50a and 50b in the same field of view. Then, based on the synthesized image of these images, the image processing device 52 is used to calculate the amount of positional deviation, and a movement command to the XYθ stage 37 is issued as the position adjustment amount. Thereby, the positions of the reference marks 61a and 61b of the glass chart 60 and the positions of the nozzle alignment marks 18a and 18b are aligned. (Step S104)

  Then, after the alignment is completed, the joint surface copying mechanism 38 is unlocked to be in a free state. The pressure stage 36 performs load control, and continues to lower the lowered position until the main pressure (60 [N]) acts as a bonding load between the integrated component 17 with the nozzle plate and the frame member 1. Increase the load with. A predetermined book pressing force acts on the adhesive. No pressure is applied to the temporary adhesive because it is applied to the pressure relief portion. In this state, for example, UV light is irradiated from four directions with a UV irradiator and fixed with a UV adhesive as a temporary adhesive. Since the liquid chamber plate and the frame are joined in a state of being sealed without any gap by the present adhesive, ink leakage from this interface does not occur. As this adhesive, for example, a thermosetting epoxy adhesive is suitable. (Step S105)

  Next, the vacuum suction of the upper suction stage 34 is released in a state where the position is fixed by temporary joining of the frame and the liquid chamber plate. Further, the joint surface copying mechanism 38 is locked. After confirming the joining accuracy at this stage, the Z-axis stage is lowered to the lowered position. Finally, the vacuum suction of the lower suction stage 31 is released, and further, the clamp mechanism of the frame is released, so that the joined product in which the liquid chamber plate to which the nozzle plate is joined and the frame are joined can be taken out. (Step S106)

  By joining in the order of the above steps S101 to S106, the positional relationship between the frame external reference position and the nozzle alignment mark is joined with high accuracy. Further, in the nozzle plate, the positional relationship between the discharge nozzle hole and the nozzle alignment mark can be processed with high accuracy by the processing machine. Therefore, it is possible to finally assemble an ink jet head in which the positional relationship between the outer shape reference position of the frame and the discharge nozzle holes is positioned with high accuracy, and it is possible to ensure high landing position accuracy of the ink jet head recording apparatus. The optical member used in the alignment apparatus is a half mirror, and even when there is a temperature change, the temperature change only affects the half mirror. For this reason, the distortion of the image of the third mark acquired through each optical path is the same as the image of the first mark or the fourth mark, and the position of the third mark and the position of the first mark or the fourth mark are the same. There is little influence on checking whether or not the position of the mark matches. Furthermore, the number of times the light from the light source passes through the half mirror in one optical path is two times, the forward path and the return path, and the amount of light emitted from the light source and incident on the imaging means is less attenuated. An auxiliary lighting fixture is not required, and image distortion due to an increase in the temperature of the optical member due to the temperature of illumination does not occur.

What has been described above is merely an example, and the present invention has a specific effect for each of the following modes.
(Aspect 1)
When assembling the nozzle plate to the head frame of the droplet discharge head, the head frame is installed in an alignment device that positions the head frame and the nozzle plate based on an image obtained by imaging the first mark corresponding to the nozzle plate by the imaging means. A second frame provided in a direction different from the head frame installation unit with respect to the imaging means, and a first mark corresponding to the nozzle plate on the head frame installed in the head frame installation unit. an optical system consisting of a single half mirror Ru is imaged in the same imaging device, the same field of view on the first mark and in the second mark to adjust the position by moving the head frame to the nozzle plate to match adjusted Means. According to this, as described in the above embodiment, the optical path of the light emitted from the light source is divided into two optical paths by the half mirror 43a, and images are formed at two locations. Then, the image of the reference mark 61a positioned at the reference position by one optical path and the image of the alignment mark 18a by the other optical path are captured in the same field of view, and the reference mark 61a and the alignment mark 18a coincide. Positioning adjustment is performed to This positioning adjustment is performed by one half mirror 43a as an optical member. The alignment mark 18a of the nozzle plate installed on the frame member of the inkjet head and the reference mark 61a of the reference member are in different directions with respect to the imaging means. For this reason, the directions of the optical paths on the objective side in the optical system for forming the alignment mark 18a of the nozzle plate and the reference mark 61a on the same imaging means 50a are different from each other. Thereby, unlike an alignment apparatus using a conventional bifocal microscope, it is possible to omit an optical member for making one optical path having different focal lengths toward one objective lens. Therefore, the nozzle plate can be aligned with the head frame with relatively few optical components.
(Aspect 2)
In (Aspect 1), the second mark and the first mark corresponding to the second mark are imaged in the same field of view by the imaging means, and the second mark is provided so that the second mark and the first mark coincide with each other An initial posture position adjusting means for adjusting the initial posture and position of the reference member is provided. According to this, as described in the above embodiment, the reference mark and the alignment mark can be easily matched on the image simply by making the optical axes of the light source and the half mirror substantially coincide with each other. The optical axes of the optical members can be easily aligned with each other, and the number of optical members can be reduced to reduce the influence of temperature change and improve the alignment accuracy.
(Aspect 3)
In (Aspect 1), two first marks respectively formed at both end portions in the longitudinal direction of the nozzle plate are provided with imaging means for imaging the two second marks to be aligned at two locations at the same time. . According to this, as described in the above embodiment, two alignment marks are used for one nozzle plate using two imaging means. As a result, it is possible to perform positioning with high accuracy at a position away from the attachment reference position of the frame member of the inkjet head by a target distance.
(Aspect 4)
In (Aspect 1), when adjusting the initial posture and position of the second mark, the adjustment member provided with the third mark is such that the distance from the outer shape to the third mark is the distance between the outer shape of the head frame and the first mark. It is a design value and has an attachment reference that has the same outer shape as the head frame, and is arranged at a predetermined position by the same clamping means that clamps the outer shape of the head frame. According to this, as described in the above embodiment, the initial posture and position of the reference mark are adjusted while adjusting the optical axis so that the position can be adjusted with the adjustment target mark of the master work as a target. At that time, the master work provided with the adjustment target mark can be placed at a target position with good reproducibility by a mechanism for clamping to the frame member of the inkjet head. And the position of the adjustment target mark of the master work hardly deviates from the position of the reference mark of the fixedly arranged glass chart. For this reason, even when it is necessary to adjust the position of the reference mark of the glass chart in accordance with the position of the adjustment target mark of the master work, the time required for the adjustment can be performed in a very short time.
(Aspect 5)
In (Aspect 4), the second mark and the third mark have a configuration in which quartz glass is bonded to a SUS base material, and are made of a reflective chromium film that exposes and transfers a mask pattern to the quartz glass. . According to this, as described in the above embodiment, since it is sufficient if there is a simple reflecting surface, there is no need to form a convex portion, and there is no need to form an alignment mark on the convex portion. For this reason, it can be manufactured at a very low cost. Further, since it is made of a reflective chrome film, there is no need to provide a through hole in the clamp base that clamps the frame member of the inkjet head, so that the vacuum suction of the frame member of the inkjet head can be performed easily.
(Aspect 6)
In (Aspect 2), the Z-axis stage mounted with the head frame installation portion, the reference member, the initial posture position adjusting means, and the half mirror, and integrally moving in the vertical direction, and the Z-axis stage are integrated. And an XYθ stage that moves in the XYθ direction. According to this, as described in the above embodiment, the clamping means for clamping the master work provided with the adjustment target mark, and the initial posture position adjustment for adjusting the initial posture and the position of the glass chart provided with the reference mark. The means are arranged independently. For this reason, the attitude | position and position of the glass chart which provided the reference mark can be adjusted according to the adjustment target position of a master workpiece. Therefore, the optical axis can be adjusted easily and accurately.
(Aspect 7)
In (Aspect 1), a nozzle plate holding unit that holds the nozzle plate by vacuum suction, a pressing unit that presses the nozzle plate held by the nozzle plate holding unit against the head frame fixed by the head frame setting unit, surface to be bonded of the head frame and the Nozurupu rate and means copying joint surface so as to be parallel to the pressing means. According to this, as above described, when the pressure bonding, it is not caused position shift Ru good the pressing of the pressing pin by urging means. And when joining the head member consisting of the nozzle plate integrated with the liquid chamber plate and the fixing member, after aligning each joint surface in a non-parallel state, when pressure joining via an adhesive In addition, a joining surface copying means is provided. As a result, it is possible to perform bonding with high positional accuracy without causing positional displacement during pressure bonding while maintaining alignment with high accuracy during alignment.
(Aspect 8)
In (Aspect 6), an image processing unit is provided that calculates a movement command amount to the XYθ stage as a position adjustment amount based on a positional deviation amount between the second mark and the first mark captured in the same field of view by the imaging unit. . According to this, as described in the above embodiment, it is possible to perform bonding with high positional accuracy.
(Aspect 9)
In the alignment method for positioning the head frame and the nozzle plate on the basis of the image obtained by imaging the first mark corresponding to the nozzle plate by the imaging means when the nozzle plate is assembled to the head frame of the droplet discharge head, The second mark provided in a direction different from the head frame installation part where the head frame is installed and the first mark corresponding to the nozzle plate on the head frame installed in the head frame installation part are composed of one half mirror. The optical system forms an image on the same image pickup means, picks up an image with the image pickup means, and moves the head frame relative to the nozzle plate so that the first mark and the second mark coincide with each other in the same field of view. According to this, as described in the above embodiment, the optical path of the light emitted from the light source is divided into two optical paths by the half mirror 43a, and images are formed at two locations. Then, an image of the reference mark 61a positioned at an ideal position by one optical path and an image of the alignment mark by the other optical path are captured in the same field of view, and the center of the reference mark 61a and the center of the alignment mark are obtained. Positioning adjustment is performed to match. This positioning adjustment is performed by one half mirror 43a as an optical member. The alignment mark of the nozzle plate installed on the frame member of the inkjet head and the position of the reference mark of the reference member are in different directions with respect to the imaging means. For this reason, the directions of the optical paths on the object side in the optical system for forming the alignment mark and the reference mark of the nozzle plate on the same imaging means are different from each other. Thereby, unlike an alignment apparatus using a conventional bifocal microscope, it is possible to omit an optical member for making one optical path having different focal lengths toward one objective lens. Therefore, the nozzle plate can be aligned with the head frame with relatively few optical components.

DESCRIPTION OF SYMBOLS 1 Frame member 2 Diaphragm 3 Flow path plate 4 Nozzle plate 5 Multilayer piezoelectric element 6 PZT base 7 FPC
8 Common liquid chamber 9 Pressurized liquid chamber 10 Fluid resistance portion 11 Nozzle 12 Communication hole 13 Island-shaped convex portion 14 Diaphragm portion 15 Ink inlet 16 Ink supply port 17 Integrated component 31 with nozzle plate 31 Lower suction stage 32 Clamp means 33 Clamp means 34 Upper suction stage 35 Z-axis stage 36 Pressure stage 37 XYθ stage 38 Bonding surface tracing mechanism 39 Pressure actuator 40 Guide mechanism 41 Pressure table 42 Block base 43a Half mirror 43b Half mirror 44 Glass chart fixed base 46 Master work 47a Adjustment Target mark 47b Adjustment target mark 50a CCD camera 50b CCD camera 51a Coaxial epi-illumination 51b Coaxial epi-illumination 53 Manual triaxial stage 60 Glass chart 61a Reference mark 61b Reference mark 62 Posture position adjustment means 63 Lamp bolt 64 Glass chart connecting block 70 Cylinder 71 Piston 72 Lock port 73 Free port 74 Air supply port 75 Convex spherical surface 76 Spherical member 77 Concave spherical surface 78 Receiving member 79 Receiving bearing member 81 Vacuum port 82 Vacuum port 83 Vacuum port 91 Adhesive 92 Pressurized relief part 100 Detection optical means 200 Detection optical means

Japanese Patent No. 4207074

Claims (9)

In an alignment apparatus for positioning the head frame and the nozzle plate based on an image obtained by imaging an image of a first mark corresponding to the nozzle plate when the nozzle plate is assembled to the head frame of the droplet discharge head.
A head frame installation part on which the head frame is installed;
A second mark provided in a direction different from the head frame installation portion with respect to the imaging means and a first mark corresponding to a nozzle plate on the head frame installed in the head frame installation portion are used as the same imaging means. an optical system consisting of a single half mirror Ru is imaged,
An alignment apparatus characterized by comprising: adjusting means for moving the head frame relative to the nozzle plate so as to match the first mark and the second mark on the same field of view. The alignment apparatus according to claim 1,
The second mark and the first mark corresponding to the second mark are imaged in the same visual field by the imaging means, and the second mark is provided so that the second mark and the first mark coincide with each other. An alignment apparatus comprising an initial attitude position adjusting means for adjusting an initial attitude and position of the reference member. The alignment apparatus according to claim 1,
The image pickup means for picking up images of the two second marks to be respectively aligned with two first marks respectively formed at both end portions in the longitudinal direction of the nozzle plate at two locations simultaneously. A featured alignment device. The alignment apparatus according to claim 1,
When adjusting the initial posture and position of the second mark, the adjustment member provided with the third mark is such that the distance from the outer shape to the third mark is the design value of the outer shape of the head frame and the first mark. An alignment apparatus comprising an attachment reference having the same outer shape as the head frame and disposed at a predetermined position by the same clamping means as that for clamping the outer shape of the head frame. The alignment apparatus according to claim 4, wherein
Said 2nd mark and said 3rd mark are the structures which bonded quartz glass to the SUS base material, and are produced with the chromium film for reflection which exposes and transfers a mask pattern to quartz glass, It is characterized by the above-mentioned. Alignment device. The alignment apparatus according to claim 2, wherein
A Z-axis stage mounted with the head frame installation portion, the reference member, the initial posture position adjusting means, and the half mirror and integrally moving in the vertical direction, and the Z-axis stage are integrated. An alignment apparatus comprising: an XYθ stage that moves in an XYθ direction. The alignment apparatus according to claim 1,
Nozzle plate holding means for holding the nozzle plate by vacuum suction, pressing means for pressing the nozzle plate held by the nozzle plate holding means against the head frame fixed by the head frame setting portion, and the pressing alignment and wherein a surface to be bonded of said Nozurupu rate and the head frame may have a joint surface profiling means in parallel by means. The alignment apparatus according to claim 6, wherein
Image processing means for calculating a movement command amount to the XYθ stage as a position adjustment amount based on a positional deviation amount between the second mark and the first mark imaged in the same field of view by the imaging means; A featured alignment device. In assembling the nozzle plate to the head frame of the droplet discharge head, in the alignment method for positioning the head frame and the nozzle plate based on the image obtained by imaging the first mark corresponding to the nozzle plate by the imaging means,
A second mark provided in a direction different from a head frame installation part on which the head frame is installed with respect to the imaging means; a first mark corresponding to a nozzle plate on the head frame installed in the head frame installation part; Is imaged on the same image pickup means by an optical system comprising one half mirror and picked up by the image pickup means, and the head frame with respect to the nozzle plate so that the first mark and the second mark coincide on the same field of view. An alignment method characterized by adjusting the position by moving.

Images