JP4131317B2 - Inkjet printer head and manufacturing method thereof - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a configuration of a piezoelectric type ink jet recording apparatus, and more particularly to a configuration of an ink jet printer head including a plurality of front head units and a manufacturing method thereof.
[0002]
[Prior art]
Conventionally, as an ink jet printer head for recording by ejecting ink droplets from a nozzle of a recording head on a recording medium such as paper based on an input signal, for example, it is disclosed in FIG. 10 of JP-A-5-201000. As described above, the stacked type front head unit includes a plurality of ink flow paths that receive pressure from the pressure conversion element in a plurality of stacked plates, and a nozzle that ejects ink based on the pressure on the front surface. The front head unit was fixed with an adhesive in a recess in the lower surface of the synthetic resin head holder member. The head holder member is formed with an ink flow path for allowing ink from the ink cartridge to flow into the front head unit.
[0003]
According to the conventionally known configuration, for color image formation, a plurality of front head units are arranged in parallel on one head holder member, and ink of different colors is ejected for each nozzle row. In order to prevent variations in the ink ejection positions of the nozzles with respect to the paper or to ensure that the variations are within a certain error, the plurality of front head units are parallel to each other and the intervals between them are constant. It is necessary to fix it with an adhesive after setting it with a jig or the like, and this method is disclosed in Japanese Patent Application No. 2001-23776 prior to this application. (JP 2002-144590 A) In The applicant Proposed. In the method, the nozzle plate in each front unit is provided with positioning holes that fit into positioning pins protruding from a jig at or near the front and rear portions of the nozzle row. On the other hand, the bottom plate of the head holder member is provided with a support portion for supporting the back surfaces of the plurality of front head units in parallel, and voids (through holes) where a plurality of the back surfaces of the front head units are exposed. Then, after the plurality of front head units are positioned and positioned with respect to each other by the positioning pins, the support portion is disposed opposite to the back surface of the plurality of front head units, and the quick-drying property is provided from the space (through hole). The UV adhesive was dropped to fix the head holder member and the plurality of front head units.
[0004]
[Problems to be solved by the invention]
However, even if such a fast-drying UV adhesive is used for bonding and fixing, there are the following problems, and it is possible to improve the nozzle row spacing accuracy and parallel placement accuracy between adjacent front head units. could not.
[0005]
That is, in order to reduce the weight of the head holder member, the one formed integrally with a synthetic resin material is often used. And, since the synthetic resin material generally has a large temperature expansion coefficient, when a plurality of front head units are directly fixed to the synthetic resin head holder member via an adhesive, due to a change in environmental temperature, The interval between adjacent front head units may fluctuate or tilt.
[0006]
In forming a color image, ink droplets (grains) of a plurality of colors are ink-jetted so as to overlap and color the same spot on the surface of a recording medium such as paper, thereby achieving a desired color gradation. Since the distance between the nozzle row in one front head unit and the nozzle row in the other (adjacent) front head unit is larger than the reference interval due to a temperature rise or tilted, for example, The ink coloring points of a plurality of colors on the recording medium are shifted, color shift occurs, the sharpness (resolution) of the image is lowered, and the quality of the color image is deteriorated.
[0007]
The present invention has been made to solve such problems, and maintains the nozzle row spacing accuracy and parallelism substantially constant regardless of environmental temperature changes when a plurality of front head units are arranged adjacent to each other. It is a technical problem to provide an ink jet printer head which can be made and does not deteriorate image quality.
[0008]
[Means for Solving the Problems]
In order to achieve this technical problem, an ink jet printer head according to a first aspect of the present invention includes a plurality of front head units having a plurality of nozzles arranged in a row on the front surface, and the front head units. While supporting the front of the A cover plate having an opening window through which the nozzle row can be exposed; In the bottom plate of the holder member facing the back surface opposite to the front surface of the front head unit and the cover plate In an inkjet head unit that is fixed to the lower surface with an adhesive, The cover plate is arranged in parallel so that the front surfaces of a pair of front head units arranged in parallel with the nozzle rows are positioned in a state where the nozzle rows are exposed to the opening windows. The perforated opening window is provided, and supports the front surface of each front head unit with respect to the back surface of the cover plate in advance, and the nozzle row is exposed from each opening window. Each front head unit is positioned, bonded and fixed, and a position of a through hole formed in the bottom plate corresponds to an intermediate position between the arrangement positions of the pair of adjacent front head units arranged side by side, and It is set so as to correspond to the back surface of the cover plate between the opening windows drilled in parallel, and the back surface of the cover plate and the front head. A position corresponding to the adjacent side edges of the rear surface of the tripartite and the bottom plate, that the adhesive is filled in the through-hole is interposed It is characterized by being fixed.
[0009]
On the other hand, the manufacturing method of the ink jet printer head of the invention according to claim 2 A plurality of front head units having a plurality of nozzles arranged in a row on the front surface; and a cover plate supporting the front surface of each front head unit and having an opening window through which the nozzle rows can be exposed; In the method of manufacturing an ink jet head unit, which is fixed to the lower surface of the bottom plate of the holder member facing the back surface opposite to the front surface of the front head unit and the cover plate with an adhesive, the cover plate is formed in parallel with the cover plate. With the nozzle row exposed to each opening window, a pair of front head units arranged in parallel with the nozzle row are set so that the front surface thereof is positioned, and then the cover plate And supporting the front surface of each front head unit against the back surface of Each front head unit is positioned and bonded and fixed so that the nozzle row is exposed from each opening window, and then corresponds to an intermediate position between the arrangement positions of the pair of adjacent front head units arranged in parallel. And, after setting the position of the through hole drilled in the bottom plate so as to correspond to the back surface of the cover plate between the opening windows drilled in parallel, the back surface of the cover plate, Fill the through hole with an adhesive so as to fix the bottom plate with the position corresponding to the adjacent side edge of the back surface of the front head. It is characterized by this.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. 1 is a schematic plan view of an ink jet recording apparatus to which the present invention is applied, FIG. 2 is a plan view of an ink jet head unit mounted on a scanning carriage, FIG. 3 is a side sectional view of the ink jet head unit mounted on a scanning carriage, and FIG. FIG. 5 is a perspective view showing a state in which the scanning carriage and the inkjet head unit are separated from each other, FIG. 5 is a side sectional view of the inkjet head unit, and FIG. 6 is a diagram showing a method for bonding and fixing a cover plate with a front head unit to a holder member. 7 is a perspective view of a holder member and a plurality of front head units fixed to the cover plate, FIG. 8 is a plan view of the holder member, and FIG. 9 is a state in which the cover plate with the inkjet head unit is fixed to the holder member. It is a principal part sectional view shown.
[0011]
First, the main part of the ink jet recording apparatus 1 will be described with reference to FIG. 1. The frame 4 in the main body case 2 of the ink jet recording apparatus 1 has a horizontal direction (arrow X direction in FIG. 1, hereinafter referred to as a main scanning direction). ), Both ends of the long main guide rail 3 and the sub guide rail 45 are fixed. On the main guide rail 3 and the sub guide rail 45, a scanning carriage 6 on which the ink jet head unit 5 is detachably attached is attached so as to be able to reciprocate in the left and right directions. It is configured to reciprocate in the main scanning direction within a predetermined range. A sheet P as an example of a recording medium is conveyed in the Y direction (hereinafter referred to as a sub-scanning direction) in FIG. For this purpose, as shown in FIG. 3, a transport device comprising a pair of transport rollers 12a, 12b on the upstream side in the transport direction and a pair of transport rollers 12c, 12d on the downstream side is provided below the inkjet head unit 5. Yes.
[0012]
The inkjet head unit 5 includes a front head unit 10 on the lower surface and a container housing 24 integrally formed with four flow paths capable of individually supplying four color inks, and a holder member 7 having an open upper surface. The holder member 7 will be described in detail later. Ru In this manner, the scanning carriage 6 is detachably connected in a substantially horizontal direction.
[0013]
In FIG. 1, below the transport surface of the paper P, four ink supply sources that can separately store four colors (magenta (red), yellow (yellow), cyan (blue), and black (black)) of ink. The ink cartridges 8 (individual symbols are 8a, 8b, 8c, 8d) are arranged in a horizontal row. The distal end of a flexible ink supply tube 11 (individual reference numerals 11a to 11d) made of synthetic resin or the like whose base ends are connected to the ink cartridges 8a to 8d is fixed in the scanning carriage 6. The ink supply joint member 9 is connected, and ink is supplied from the joint member 9 to the front head unit 10 via the ink flow path in the container casing 24.
[0014]
In the embodiment, two front head units 10 are arranged in parallel, and each front head unit 10 has two rows of nozzles in which a large number of nozzles are arranged in a row, and the nozzle rows are in the sub-scanning direction. It arrange | positions so that it may extend in (Y direction of FIG. 1). As will be described later, in order to form a color image, each column of nozzles is divided into four colors (magenta (red), yellow (yellow), cyan (blue), and black (black)). The inks of the respective colors are ejected downward from the nozzles on the lower surface of each front head unit 10 and are attached to the surface of the paper P (see FIG. 3).
[0015]
Further, a suction cap 13 for recovery operation (suction purge) and the surface of each front head unit 10 are wiped and cleaned at the left end portion (end portion within the moving range of the scanning carriage 6) of the main body case 2 in FIG. The wiper blade 14 is arranged so as to face the front head unit 10, and at the time of suction purge, the suction cap 13 is close and close to cover the nozzle part on the front surface (lower surface) of the front head unit 10. Is configured to do. The suction pipe 15 connected to the suction cap 13 is connected to a disposal tank, for example, a disposal area in the ink cartridge 8 (one of the ink cartridges 8a to 8d) via a suction pump (not shown). The waste ink sucked out is discharged to the location (discard area). As an apparatus for the recovery operation, there is a method of applying a high pressure to the ink from the ink supply side of the head in addition to the above-described suction method.
[0016]
The configurations of the inkjet head unit 5 and the scanning carriage 6 will be described in detail with reference to FIGS. First, as shown in FIGS. 2, 3, and 4, the scanning carriage 6 includes a base portion 6 a that fits over the main guide rail 3, and a front portion of the main body case 2 from the base portion 6 a (arrangement position of the ink cartridge 8). And a pair of left and right support frames 6c and 6c extending further forward from the joint storage portion 6b are integrally formed of a synthetic resin material. .
[0017]
The synthetic resin joint member 9 fixed in the joint housing portion 6b is a sealed box body that is long on the left and right sides, and is provided in openings on both the left and right sides of the joint member 9, as shown in FIG. The other ends of the synthetic resin supply pipes 11a to 11d connected to the ink cartridges 8a to 8d are fitted into the connection ports 16a to 16d. In that case, as shown in FIG. 3 and FIG. 4, notch grooves 20 and 20 are formed on both the left and right sides of the joint housing portion 6b, and the middle portions of the supply pipes 11a to 11d are formed in the notch grooves 20 and 20, respectively. By making it pass, each supply pipe | tube 11a-11d is comprised so that it can connect with respect to the connection ports 16a-16d of the said joint member 9 with a substantially horizontal state.
[0018]
In the joint member 9, a flow path (not shown) is provided so that each of the connection ports 16a, 16b, 16c, and 16d communicates with the ink discharge ports 19a, 19b, 19c, and 19d. . Each of the ink discharge ports 19 a to 19 d is formed so as to protrude forward from the front surface of the joint member 9 in a substantially horizontal shape.
[0019]
On the other hand, the container housing 24 is fixed on the bottom plate 7a of the holder member 7 made of an injection molded product of a synthetic resin material such as polypropylene or polypropylene. Air traps 23 (individual symbols for each color are 23a, 23b, 23c, and 23d) are formed in the four flow paths in the container casing 24, corresponding to the nozzle rows of four colors, and capable of trapping bubbles. Has been.
[0020]
Four ink inlets 21 (individual reference numerals 21a, 21b, 21c, and 21d) are formed in the container casing 24 so as to protrude rearward and substantially horizontally, and each of the joint members 9 in the scanning carriage 6 has the above-described respective shapes. It is at a height position facing the ink discharge port 19 (individual reference numerals 19a, 19b, 19c, 19d). When the ink introduction port 21 and the ink discharge port 19 are connected, the ink introduction ports 21a to 21d are connected to the respective ink introduction ports 21a to 21d via the cylindrical seal rings 22 fitted to the ink discharge ports 19a to 19d. The outer periphery is sealed. The seal ring 22 is preferably made of silicone rubber, urethane rubber, nitrilo rubber (NBR), isoprene rubber, butylene rubber, fluorine-based rubber or the like as an elastic body. Accordingly, the ink enters each air trap 23 from each ink introduction port 21 through the supply pipe 11 and the joint member 9 from each ink cartridge 8 and is supplied to each nozzle row.
[0021]
Next, the configuration of the front head unit 10 and the configuration and method for fixing the arrangement of the nozzle rows in the plurality of front head units to the lower surface of the bottom plate 7a of the holder member 7 while accurately holding it will be described. To do.
[0022]
First, details of the front head unit 10 and its components will be described. As shown in FIG. 10, the front head unit 10 includes a plurality of metal plate laminated cavity plate units 27, and an adhesive or an adhesive sheet 29 (see FIG. 14) for the cavity plate units 27. A plate-type piezoelectric actuator 28 that is bonded and laminated via a flexible flat cable 35 is overlapped and bonded to an external device on the upper surface thereof.
[0023]
Further, as will be described later, the dust in the ink supplied from the container housing 24 is formed on the back surface side of the front head unit 10 and on the upper surface of the supply hole 59a formed in one end of the uppermost base plate 53. A filter 60 for removal is fixed in advance with an adhesive (see FIG. 9).
[0024]
The cavity plate unit 27 is configured as shown in FIGS. That is, the nozzle plate 54 has a structure in which four thin metal plates, ie, two manifold plates 50 and 51, a spacer plate 52, and a base plate 53 are laminated and bonded with an adhesive, respectively. Each of the four plates is made of 42% nickel alloy steel plate and has a thickness of about 50 μm to 150 μm. The nozzle plate 54 is provided with nozzles 55 in a zigzag array in two rows along the first direction (long side direction). That is, a large number of nozzles 55 are formed in a staggered arrangement at intervals of a minute pitch P along two parallel reference lines 54a and 54b extending in the first direction. In the two manifold plates 50, 51, ink passages 50 a, 51 a are formed so as to extend along both sides of the row of the nozzles 55. However, the ink passage 50a in the lower manifold plate 50 is formed as a recess so as to open only to the upper side of the manifold plate 50 (see FIG. 12). The ink passage 51 a in the upper manifold plate 51 is formed so as to penetrate the thickness of the manifold plate 51, and the ink passages 50 a and 51 a are sealed by stacking the spacer plate 52 on the upper manifold plate 51. It has become.
[0025]
The base plate 53 is provided with a plurality of narrow pressure chambers 57 extending in a second direction (short side direction) perpendicular to the center line along the long side (first direction). Has been. Then, as shown in FIG. 12, when parallel longitudinal reference lines 53a and 53b are set on both the left and right sides with the center line in between, the front end 57a of the pressure chamber 57 on the left side of the center line becomes the left longitudinal reference line. On the contrary, the tip 57a of the pressure chamber 57 on the right side of the longitudinal center line is located on the right longitudinal reference line 53a, and the tips 57a of the right and left pressure chambers 57 are alternately arranged. Therefore, every other pressure chamber 57 on the left and right sides is alternately arranged so as to extend in opposite directions.
[0026]
The front end 57a of each pressure chamber 57 is connected to the nozzle in the nozzle plate 54 via minute diameter communication passages 56, 56, 56 formed in the spacer plate 52 and the manifold plates 50, 51 in a staggered arrangement. 55 is communicated. On the other hand, the other end 57b of each pressure chamber 57 communicates with the ink passages 50a and 51a in the manifold plates 50 and 51 through the through holes 58 formed in the left and right sides of the spacer plate 52. Yes.
[0027]
As shown in FIGS. 12 and 14, the other end 57 b of each pressure chamber 57 is recessed so as to open only on the lower surface side of the base plate 53. Further, supply holes 59a and 59b communicating with the ink flow paths 50a and 51a are formed in one end portions of the uppermost base plate 53 and the spacer plate 52, respectively.
[0028]
As a result, ink that has flowed into the ink passages 50a and 51a from the supply holes 59a and 59b drilled in one end of the base plate 53 and the spacer plate 52 passes through the through holes 58 from the ink passage 51a. After being distributed in each pressure chamber 57, the pressure chamber 57 passes through the communication passages 56, 56, 56 and reaches the nozzle 55 corresponding to the pressure chamber 57 (see FIG. 11).
[0029]
On the other hand, the piezoelectric actuator 28 has a structure in which a plurality of piezoelectric sheets 61 are laminated as shown in FIGS. 13 and 14, and each of the piezoelectric sheets 61 is the same as that described in JP-A-4-341851. Of the lowermost piezoelectric sheet 61 and the upper surface (wide surface) of the even-numbered piezoelectric sheet 61 counting upward from the lower piezoelectric sheet 61, narrow individual electrodes (for each location of each pressure chamber 57 in the cavity plate unit 27). (Not shown) are formed in a row along the first direction (long side direction). A common electrode (not shown) common to the plurality of pressure chambers 57 is formed on the upper surface (wide surface) of the odd-numbered piezoelectric sheet 61 from the bottom. On the upper surface of the uppermost top sheet, a surface electrode 62 electrically connected to each of the individual electrodes and a surface electrode 63 electrically connected to the common electrode are provided. (See FIG. 13).
[0030]
In the plate-type piezoelectric actuator 28 having such a configuration, each individual electrode in the piezoelectric actuator 28 corresponds to each pressure chamber 57 in the cavity plate unit 27 with respect to the cavity plate unit 27. Are laminated and fixed. Further, the flexible flat cable 35 is overlaid and fixed on the upper surface of the piezoelectric actuator 28, so that various wiring patterns (not shown) in the flexible flat cable 35 are formed on the surface electrodes 62 and 63. (See FIG. 10).
[0031]
In this configuration, by applying a voltage between an arbitrary individual electrode among the individual electrodes in the piezoelectric actuator 28 and the common electrode, a portion corresponding to the individual electrode to which the voltage is applied in the piezoelectric sheet 61 is applied. A distortion in the stacking direction due to piezoelectricity occurs, and the ink in the pressure chamber 57 is ejected from the nozzle 55 in the form of droplets by this distortion, and predetermined printing is performed.
[0032]
The number of the front head units 10 to be paralleled is 2 And 4 so that the two front head units 10 are paired. The cavity plate unit 27 in the front head unit may be a ceramic material in addition to a metal material. Further, the driving means of the ink jet printer of the present invention may be other types of the plate-like piezoelectric actuator 28 described above, or the vibration plate that covers the back surface of the pressure chamber is vibrated by static electricity so that ink is ejected from the nozzle 55. It is also possible to have a configuration in which the liquid is discharged from
[0033]
Next, the plurality (in the present embodiment, 2 pairs The structure and method for assembling the front head unit 10 to the holder member 7 will be described. First, as shown in FIGS. 6 and 7, the two front head units are attached to the cover plate 31 made of a thin metal plate. 10 and 10 are positioned and bonded and fixed in parallel. In that case, two opening windows 31a and 31a are formed in the cover plate 31 by pressing so as to surround the outer peripheral edge of the nozzle plate 54 in each front head unit 10 with an appropriate gap dimension. Keep it.
[0034]
On the other hand, positioning holes 64 and 65 are formed in advance in the front and rear end portions of the front head unit 10 in the longitudinal direction of the nozzle plate 54 (see FIG. 11). Positioning pins 67 and 67 that fit into the positioning holes 64 and 65 in the front head units 10 are provided on the surface of the positioning jig 66 shown in FIG. After the cover plate 31 is placed, a thermosetting adhesive such as an epoxy resin is provided on the back surface of the cover plate 31 on the outer periphery of the opening window 31a and in an area area facing the front head unit 10 surface. Then, the positioning holes 64 and 65 are fitted into the positioning pins 67 and 67 of the jig 66 and the front head units 10 and 10 are pressed against the cover plate 31 and heated. The two front head units 10 and 10 are arranged and fixed in parallel to the cover plate 31 at a predetermined interval. In that case, it is desirable that the cover plate 31 is slightly thicker than the nozzle plate 54.
[0035]
When the cover plate 31 is bonded and fixed to the lower surface side of the bottom plate 7a of the holder member 7, as shown in FIG. 7, the two front panels arranged in parallel are arranged at the substantially central portion of the wide surface of the bottom plate 7a. A plurality of through-holes 69 are formed in advance so as to be arranged in a line in the approximate middle of the arrangement positions of the head units 10 and 10. Further, a cavity 71 into which each front head unit 10 can be fitted is formed in the bottom surface of the bottom plate 7a.
[0036]
The cover plate 31 and the plurality of front head units 10, 10 are opposed to the lower surface side of the holder member 7, and an adhesive 70 such as thermoplastic is hung on the through holes 69 from the upper surface side of the bottom plate 7 a. The back surface of 31 (may be part of the back surface of the front head unit 10) and the bottom plate 7a are connected and fixed (see FIG. 9). In this manner, the plurality of front head units 10 are fixed (adhered) to the single metal cover plate 31 in advance with a predetermined accuracy (within an allowable error range). When the object is connected to the bottom plate 7a of the holder member 7 having a larger temperature expansion coefficient (linear expansion coefficient) than the cover plate 31, only the substantially central portion of the wide surface of the cover plate 31 and the substantially central portion of the bottom plate 7a are bonded. If fixed, even if the entire size of the bottom plate 7a is expanded or contracted in accordance with the temperature change of the environment, the center position in the width direction of the bottom plate 7a (the direction in which the plurality of front head units 10 are arranged in parallel) and thus the cover. The connection part with the plate 31 is not displaced.
[0037]
In particular, if the adhesive strength of the front head unit 10 to the cover plate 31 is set high and the adhesive strength between the cover plate 31 and the bottom plate 7a is set relatively low, the nozzles 55 of the plurality of front head units 10 due to environmental temperature changes. The change in dimension between them depends only on the temperature expansion coefficient of the cover plate 31 made of metal, and is not affected by the expansion or contraction due to the temperature change of the bottom plate 7a made of synthetic resin.
[0038]
Note that the gap between the outer peripheral portion of the cover plate 31 and the outer periphery of the bottom plate 7a is weak in adhesive strength, such as silicone rubber that prevents ink or dust from entering the holder member 7 side from the outer peripheral edge of the cover plate 31. It is preferable to seal with a sealing material 72.
[0039]
If the container case 24 is fixed to the upper surface of the bottom plate 7a after the front head unit 10 is fixed to the bottom plate 7a of the holder member 7 as described above, each air trap in the container case 24 is fixed as shown in FIG. Ink passes through the filter 25 for each color in the ink 23 and is supplied from the filter 60 on the upper surface of each cavity plate unit 27 into the supply hole 59a from the passage 26 through the tubular member 73.
[0040]
Further, as shown in FIGS. 2, 3, and 4, a printed circuit board 32 as an example of a control circuit board is fixed to the upper surface side of the holder member 7, and the upper surface of the printed circuit board 32 is fixed. A horizontally long connector 33 is fixed substantially parallel to the main guide rail 3. The connector 33 has an upper lid 33b that rotates up and down with respect to the main body 33a, and a large number of contacts are arranged on the upper surface of the main body 33a at a constant pitch (0.5 m pitch in the embodiment) in the longitudinal direction. ing. Each terminal part of the other end of the flexible flat cable 34 whose one end is connected to an external device such as a computer (not shown) or a controller in the body case 2 is mounted on the body part 33a so as to be aligned with the respective contacts. When the upper lid 33b is closed, electrical continuity between each terminal and the contact becomes possible. On the other hand, a flat cable 35 having one end soldered to the lower surface side of the printed circuit board 32 is outside the container housing 24 and is disposed on the front head unit via a side surface opposite to the arrangement side of the ink inlet 19. 10 is fixed to the actuator 28 and electrically connected.
[0041]
Thus, normally, in a state where the flat cable 34 is connected to the connector 33, an instruction and image for image formation from an external device such as a computer (not shown) or a controller in the main body case 2 via the flat cable 34. A driving electric signal such as data is transmitted to the printed circuit board 32 to drive the actuator 28.
[0042]
As will be described later, when removing the holder member 7 from the scanning carriage 6, if the upper lid 33 b is opened upward, the contacts of the main body 33 a and the terminal portions of the flat cable 34 are easily detached. The holder member 7 can be easily maintained and replaced.
[0043]
Next, a configuration for attaching / detaching and fixing the holder member 7 to / from the scanning carriage 6 will be described. 2, 3, and 4 show an embodiment of the scanning carriage 6. The scanning carriage 6 is substantially horizontal on the lower edge of each inner surface of the plate-like support frames 6 c and 6 c (an example of a support portion) on both the left and right sides. Guide rails 40, 40 extending forward are provided in the shape, and on the left and right outer surfaces of the holder member 7, concave groove-shaped guide grooves 41 to be fitted to the respective guide rails 40 are formed. The guide rail 40 and the guide groove 41 are an example of a pair of support means for approaching and guiding the joint member 9 in a direction substantially parallel to the nozzle arrangement surface of the front head unit 10. A protruding guide rail may be formed on the holder member 7 side, and a concave groove may be formed on the support frames 6 c and 6 c side of the scanning carriage 6.
[0044]
Further, both base end portions 42a, 42a of the ends of both legs 42b, 42b of the tension fixture 42 made of a bent metal wire or the like having a substantially U-shape in plan view are bent inwardly of the holder member 7. It is rotatably mounted on the front part (the side far from the base 6a) on the left and right side surfaces.
[0045]
On the other hand, between the base portion 6a and the joint housing portion 6b, an engaging portion 42c that connects between the tips of the legs 42b and 42b of the tension fixture 42 is fitted and engaged with the upper surface of the scanning carriage 6. A groove-shaped engagement fixing portion 43 is formed.
[0046]
According to the above configuration, during maintenance such as exchanging the front head unit 10 or the container housing 24 in the holder member 7, as described above, after removing the flat cable 34 from the connector 33, The engaging portion 42c of the fitting 42 is removed from the engaging and fixing portion 43 of the scanning carriage 6 and pulled out in the horizontal direction, and after performing a predetermined replacement operation or the like, it is mounted on the main guide rail 3 as shown in FIG. From the state in which the holder member 7 is separated from the scanning carriage 6, the holder member 7 with the front head unit 10 mounted on the lower surface between the support frames 6 c and 6 c on the left and right sides of the scanning carriage 6 is substantially horizontal. Insert into. That is, the holder member 7 is inserted into the scanning carriage 6 with the rearward ink introduction port 21 at the rear end thereof facing the forward ink discharge port 19 in the scanning carriage 6. As a result, the guide grooves 41, 41 on both the left and right sides of the holder member 7 are guided by the guide rails 40, 40 on the inner surfaces of the support frames 6c, 6c, and all the ink introduction ports 21 are cylinders in the corresponding ink discharge ports 19. While being fitted into the seal ring 22, the ink discharge ports 19 are brought into contact with each other and both flow paths are in communication with each other. In this state, the tension fixture 42 as the engaging means is rotated so that the left and right legs 42b and 42b surround the outer sides of the support frames 6c and 6c on the left and right sides of the scanning carriage 6, and the tension fixture 42 itself. The engaging portion 42c is engaged and fixed to the groove-like engaging fixing portion 43 on the upper surface of the scanning carriage 6 by utilizing the elastic force of the above. As a result, the holder member 7 is prevented from being detached from the scanning carriage 6 and all the ink introduction ports 21 can be in close contact with the corresponding ink discharge ports 19, thereby reliably preventing ink leakage from that portion. It can be done.
[0047]
After performing the engagement and fixing operation, the electrical connection operation can also be completed by aligning the terminal portion of the flat cable 34 with each contact in the main body portion 33a of the connector 33 and closing the upper lid 33b. Since the flat cable 34 and the connector 33 are arranged on the upper surface side of the scanning carriage 6 and the holder member 7 (on the side opposite to the nozzle arrangement surface of the front head unit 10), maintenance workers can flatten in a large work space. The cable 34 can be easily attached and detached.
[0048]
The engagement means for connecting and engaging the scanning carriage 6 and the holder member 7 so as not to be disengaged is such that the above-mentioned U-shaped tension fixture 42 is mounted on the side of the scanning carriage 6 so that the base end thereof is rotatable, A groove-like engagement fixing portion 43 may be provided on the member 7 side. Further, instead of the wire-like tension fixture 42, a hook lever-like one may be configured to be engaged and disengaged.
[0049]
Then, a sub guide rail 45 (see FIG. 3) is fitted into the substantially horizontal guide groove 44 on the front end side of the holder member 7, and the sub guide rail 45 is fixed to the frame 4 of the main body case 2 or the like. For example, the ink jet head unit 5 is supported at both ends by the main guide rail 3 as one guide member and the sub guide rail 45 as the other guide member, and the nozzle surface of the front head unit 10 on the lower surface of the holder member 7 In addition, the inkjet head unit 5 can be reciprocated in the main scanning direction while maintaining a constant gap with the conveyance path of the paper P.
[0050]
【The invention's effect】
As described above in detail, the ink jet printer head according to the first aspect of the present invention includes a plurality of front head units having a plurality of nozzles arranged in a line on the front surface, and the front head units. While supporting the front of the A cover plate having an opening window through which the nozzle row can be exposed; In the bottom plate of the holder member facing the back surface opposite to the front surface of the front head unit and the cover plate In an inkjet head unit that is fixed to the lower surface with an adhesive, The cover plate is arranged in parallel so that the front surfaces of a pair of front head units arranged in parallel with the nozzle rows are positioned in a state where the nozzle rows are exposed to the opening windows. The perforated opening window is provided, and supports the front surface of each front head unit with respect to the back surface of the cover plate in advance, and the nozzle row is exposed from each opening window. Each front head unit is positioned, bonded and fixed, and a position of a through hole formed in the bottom plate corresponds to an intermediate position between the arrangement positions of the pair of adjacent front head units arranged side by side, and It is set so as to correspond to the back surface of the cover plate between the opening windows drilled in parallel, and the back surface of the cover plate and the front head. A position corresponding to the adjacent side edges of the rear surface of the tripartite and the bottom plate, that the adhesive is filled in the through-hole is interposed It is characterized by being fixed.
[0051]
With this configuration, a plurality of front head units that are previously fixed (adhered) to a single cover plate with a predetermined accuracy (within an allowable error range) are arranged and parallel. When connecting to the bottom plate of the holder member, which has a coefficient of thermal expansion significantly different from that of the cover plate, if only the approximate center portion of the wide surface of the cover plate and the approximately center portion of the bottom plate are bonded and fixed, the temperature changes in the environment. Even if the entire size of the bottom plate is expanded or contracted, the interval accuracy and parallelism of the nozzle rows can be made constant, and the image quality is not deteriorated by the environmental temperature. Particularly in the case of forming a color image, there is an effect that no color shift occurs.
[0052]
On the other hand, the manufacturing method of the ink jet printer head of the invention according to claim 2 A plurality of front head units having a plurality of nozzles arranged in a row on the front surface; and a cover plate supporting the front surface of each front head unit and having an opening window through which the nozzle rows can be exposed; In the method of manufacturing an ink jet head unit, which is fixed to the lower surface of the bottom plate of the holder member facing the back surface opposite to the front surface of the front head unit and the cover plate with an adhesive, the cover plate is formed in parallel with the cover plate. With the nozzle row exposed to each opening window, a pair of front head units arranged in parallel with the nozzle row are set so that the front surface thereof is positioned, and then the cover plate And supporting the front surface of each front head unit against the back surface of Each front head unit is positioned and bonded and fixed so that the nozzle row is exposed from each opening window, and then corresponds to an intermediate position between the arrangement positions of the pair of adjacent front head units arranged in parallel. And, after setting the position of the through hole drilled in the bottom plate so as to correspond to the back surface of the cover plate between the opening windows drilled in parallel, the back surface of the cover plate, Fill the through hole with an adhesive so as to fix the bottom plate with the position corresponding to the adjacent side edge of the back surface of the front head. It is characterized by that is there. In this way, the image quality can be prevented from deteriorating due to the environmental temperature only by devising the bonding and fixing portion between the cover plate and the bottom plate of the holder member, and this method does not increase the manufacturing cost. There is an effect.
[Brief description of the drawings]
FIG. 1 is a plan view of an ink jet recording apparatus according to an embodiment of the present invention.
FIG. 2 is a plan view of the inkjet head unit.
FIG. 3 is a side view of the inkjet head unit.
FIG. 4 is a perspective view of the scanning carriage with a holder member removed.
FIG. 5 is a side sectional view of a holder member.
FIG. 6 is a cross-sectional view of an essential part showing a method for adhering and fixing a cover plate with a front head unit to a holder member.
FIG. 7 is a perspective view of a cover plate with a holder member and a front head unit.
FIG. 8 is a front view of a holder member.
9 is a cross-sectional view taken along the line IX-IX in FIG.
FIG. 10 is a perspective view of each part of the front head unit.
FIG. 11 is a perspective view showing a defective configuration of the cavity plate unit.
FIG. 12 is a perspective view showing a main part of the cavity plate unit.
FIG. 13 is a perspective view showing a positional relationship in which piezoelectric actuators are stacked on a cavity plate unit.
FIG. 14 is an enlarged cross-sectional view of a main part of the front head unit.
[Explanation of symbols]
3 Main guide rail
5 Inkjet head unit
6 Scanning carriage
7 Holder member
7a Bottom plate
9 Joint members
10 Front head unit
11 Ink supply pipe
19 Ink ejection port
21 Ink inlet
24 container case
27 Cavity plate unit
28 Piezoelectric actuator
31 Cover plate
3a Open window
32 Printed Circuit Board
35 Flexible flat cable
54 Nozzle plate
55 nozzles
69 Through-hole
70 Adhesive

Claims (2)

A plurality of front head unit having a plurality of nozzles arranged in a row on the front, along with supporting the front of the respective front head unit, and a cover plate having an opening window that nozzle row can be exposed, the In the inkjet head unit, which is fixed to the lower surface of the bottom plate of the holder member facing the back surface opposite to the front surface of the front head unit and the cover plate with an adhesive,
The cover plate is arranged in parallel so that the front surfaces of a pair of front head units arranged in parallel with the nozzle rows are positioned in a state where the nozzle rows are exposed to the opening windows. The perforated opening window is provided,
The front head units are positioned and bonded and fixed in advance so that the front surfaces of the front head units are supported on the back surface of the cover plate and the nozzle rows are exposed from the opening windows. ,
The position of the through hole drilled in the bottom plate corresponds to an intermediate position between the positions of the pair of adjacent front head units arranged in parallel and between the opening windows drilled in parallel. Set to correspond to the back of the cover plate,
The back plate of the cover plate, the position corresponding to the adjacent side edge of the back surface of the front head, and the bottom plate are fixed by interposing an adhesive filling the through hole . An inkjet printer head characterized by the above. A plurality of front head units having a plurality of nozzles arranged in a row on the front surface; and a cover plate supporting the front surface of each front head unit and having an opening window through which the nozzle rows can be exposed; In the manufacturing method of the inkjet head unit, which is fixed to the lower surface of the bottom plate of the holder member facing the back surface opposite to the front surface of the front head unit and the cover plate with an adhesive,
The front surface of a pair of front head units arranged in parallel with the nozzle row is positioned in a state where the nozzle row is exposed with respect to the opening windows formed in parallel in the cover plate. Set as
Next, the front head unit is positioned and bonded and fixed to the back surface of the cover plate so that the front surface of the front head unit is supported and the nozzle row is exposed from the opening windows. ,
Next, so as to correspond to an intermediate position between the positions of the pair of adjacent front head units arranged side by side, and to correspond to the back surface of the cover plate between the opening windows formed in parallel. After setting the position of the through hole drilled in the bottom plate,
The adhesive is filled in the through-hole so as to fix the three of the back plate of the cover plate, the position corresponding to the adjacent side edge of the back surface of the front head, and the bottom plate. Inkjet printer head manufacturing method.

Images