JP2005138523A - Head module, liquid ejecting head, liquid ejector, manufacturing process of head module and manufacturing process of liquid ejecting head - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To form a head ensuring high positional accuracy between a head chip and a nozzle sheet and applicable to a line head without increasing a manufacturing cost. <P>SOLUTION: The head module comprises a head chip 20 arranged with heating resistors 22, a nozzle sheet 13 on which nozzles 13a are formed, and a barrier layer 12 for forming an ink liquid chamber 14 wherein a particle spacer 17 composed of particles having a diameter not larger than the thickness of the barrier layer 12 is arranged between the head chip 20 and the nozzle sheet 13. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a head module used as a head for discharging liquid in a liquid discharge apparatus such as an ink jet printer, a liquid discharge head, a manufacturing method thereof, and a liquid discharge apparatus. More specifically, the present invention relates to a technique for forming an inexpensive and highly accurate head module and a liquid discharge head by making the distance between the head chip and the nozzle sheet constituting the head module easy and constant.

Conventionally, an ink jet printer is known as an example of a liquid ejecting apparatus, and most of the printer heads of the ink jet printer are serial heads.
As a method for manufacturing a serial head, a liquid chamber forming member is laminated on a head chip on which energy generating elements are arranged, and a nozzle sheet on which nozzles are formed is joined to the liquid chamber forming member to form a printer head, or a metal plate On a substrate made of glass or glass, a fine groove is formed by cutting or etching to form an ink flow path, and the substrate on which the flow path is formed and a top plate that serves as a lid of the flow path are joined together to form a printer head A method is known.

Here, as a method for joining the nozzle sheet or the like, a method using an adhesive is common. And when joining both, it is requested | required that it adhere | attaches accurately and correctly.
Therefore, in Patent Document 1, for example, a piezoelectric plate capable of forming a plurality of piezo elements (energy generating elements) by cutting is temporarily attached via a non-stretchable adhesive tape with respect to the cutting force and cut to form a diaphragm. A technique for bonding is disclosed.
JP-A-8-267765

Also, for example, in Patent Document 2, since it is difficult to manage the coating thickness of the adhesive and there is a risk of poor bonding, a technique using a film adhesive of an epoxy resin containing a reinforcing material made of glass fiber. Is disclosed.
Japanese Patent Laid-Open No. 11-10873

Furthermore, the ink ejection performance of the printer head is affected by the distance between the energy generating element and the nozzle sheet. Therefore, managing the thickness of the adhesive layer is also an important factor for making the printer head highly accurate. Therefore, in Patent Document 3, for example, by providing a protruding portion having the same surface as the bonding surface with the substrate on a part of the top plate and bringing the abutting portion into contact with the protruding portion, the thickness of the adhesive layer varies. Even in such a case, the positional relationship between the top plate and the substrate can always be kept constant.
JP-A-10-157114

However, in the technique of the above-mentioned Patent Document 1, the non-stretchable adhesive tape is only for preventing movement with respect to the cutting force, and is only temporarily attached, so after joining the piezoelectric plate and the vibration plate, It is necessary to remove the adhesive tape. Therefore, there exists a problem that an assembly cost becomes high.
Moreover, even if it is temporarily attached via an adhesive tape, it can only counter the cutting force, and the thickness of the adhesive layer cannot be managed.

  Moreover, in the technique of the above-mentioned patent document 2, although a coating film thickness can be managed by using a film adhesive, the positional relationship between the head chip and the nozzle sheet cannot be maintained with high accuracy. . That is, when pressure is applied during bonding, the thickness of the adhesive changes even if a reinforcing material made of glass fiber is included, so that the distance between the head chip and the nozzle sheet is not constant. Therefore, the technique of patent document 2 is only what does not produce the part which the coating film thickness of an adhesive agent is too thin, or a part too thick.

Furthermore, in the technique of the above-mentioned Patent Document 3, the positional relationship between the top plate and the substrate can be kept constant, but a separate butting portion is required. Therefore, there exists a problem that a shape becomes complicated and manufacturing cost becomes high.
In particular, when a line head is formed by a plurality of head chips, the abutting portion must be provided for each head chip, and thus the manufacturing problem becomes more serious.

In addition, the applicant of the present application has changed the discharge direction of the liquid droplets discharged from the nozzles into a plurality of directions according to Japanese Patent Application Nos. 2003-037343, 2002-360408, and 2003-55236, which are prior application technologies when not opened. We have already proposed a technique that makes it possible to make high-quality printing by making the landing position of droplets inconspicuous by making it variable.
As described above, when using a technique for positively changing the ejection direction of the liquid droplets ejected from the nozzle, a particularly high accuracy is required for the positional accuracy (interval) between the head chip and the nozzle sheet.

  Therefore, the problem to be solved by the present invention is to form a head that can be used for a line head without increasing the positional accuracy between the head chip and the nozzle sheet and increasing the manufacturing cost. is there.

The present invention solves the above-described problems by the following means.
A first aspect of the present invention is a head chip in which a plurality of energy generating elements are arranged in one direction at regular intervals, a nozzle sheet in which nozzles for discharging droplets are formed, and the head chip And a liquid chamber forming member for forming a liquid chamber between each of the energy generating elements and each of the nozzles. A head module that discharges liquid in the liquid chamber from the nozzle by an element, and a spacer made of particles having a diameter equal to or less than the thickness of the liquid chamber forming member is disposed between the head chip and the nozzle sheet. This is a head module.

According to a fourth aspect of the present invention, in the liquid discharge head according to the fourth aspect, the head module according to the first aspect supports the nozzle sheet by being bonded to one surface of the nozzle sheet, and the head chip is disposed inside. A module frame having a head chip arrangement hole formed therein, the module frame engaging with each other when the other module frames are arranged in series in the nozzle arrangement direction. The engaging portions of the plurality of head modules are engaged with each other, and the plurality of head modules are arranged in series, and are arranged in the head module arrangement hole of the head frame. And
Furthermore, a liquid discharge apparatus according to a fifth aspect of the present invention includes the liquid discharge head according to the fourth aspect.

  In the above invention, the head chip and the nozzle sheet are joined together by thermocompression bonding or the like via the liquid chamber forming member. At this time, a spacer made of particles having a diameter equal to or smaller than the thickness of the liquid chamber forming member is disposed between the head chip and the nozzle sheet. Therefore, the distance between the head chip and the nozzle sheet is held by the spacer.

  And by setting it as the head module which has arrange | positioned the head chip inside the head chip arrangement | positioning hole of a module frame provided with an engaging part, each engaging part of a module frame is engaged, and a head module is connected in series. A liquid discharge head is formed.

The energy generating element of the present invention may be a heating resistor such as a heater, a piezoelectric element such as a piezo element, MEMS, or the like, but the heating resistor 22 corresponds in the following embodiments. In addition, the liquid chamber forming member of the present invention corresponds to the barrier layer 12 in the embodiment. Furthermore, in the embodiment, the head module 10 includes the module frame 11, four head chip arrangement holes 11 b are formed in the module frame 11, and four head chips 20 are provided in one head module 10. Then, four head modules 10 are connected in series to make the length of the A4 plate, and four rows are provided, and Y (yellow), M (magenta), C (cyan), and K (black) are provided. The liquid discharge head 1 which is a four-color color line head is formed.
In the following embodiments, the spacer of the present invention corresponds to a particle spacer 17 made of heat-resistant spherical plastic fine particles having a uniform particle diameter of 10 μm.

  According to the head module of the present invention, since the spacer made of particles having a diameter equal to or smaller than the thickness of the liquid chamber forming member is disposed between the head chip and the nozzle sheet, the head chip and the nozzle sheet are connected to the liquid chamber. Even when bonded by thermocompression bonding or the like via the forming member, the distance between the head chip and the nozzle sheet is maintained at a uniform particle diameter of the spacer. Therefore, the positional accuracy between the head chip and the nozzle sheet can be easily ensured, the assembling accuracy can be improved, and the ink ejection performance can be improved.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a plan view showing a liquid discharge head 1 according to an embodiment of the present invention, and a side view (cross-sectional view) in the direction of arrow X in this plan view. FIG. 2 is a side cross-sectional view showing the head chip 20 mounted in the liquid ejection head 1 and the surrounding structure, and a plan view seen from the bottom.

  The liquid discharge head 1 is used as a head mounted on a liquid discharge apparatus (in this embodiment, a color line inkjet printer). As shown in FIG. 1, the liquid ejection head 1 includes a head frame 2, a printed circuit board 3, and a plurality of head modules 10. In the plan view of FIG. 1, four head modules 10 are connected in series in the longitudinal direction, and four head modules 10 connected in series are provided in four rows. One head is printed by four head modules 10 connected in series. In this embodiment, a liquid discharge head 1 (line head) of four colors (Y, M, C, and K) is formed. ing.

Each head module 10 is provided with four head chips 20. FIG. 2 shows one head chip 20.
The head chip 20 includes a semiconductor substrate 21 made of silicon or the like, and a heating resistor 22 (corresponding to an energy generating element in the present invention) deposited on one surface of the semiconductor substrate 21. A connection pad 23 made of aluminum is formed on the edge of the semiconductor substrate 21 on the same side as the surface on which the heating resistor 22 is formed and opposite to the edge on which the heating resistor 22 is formed. . The heating resistor 22 and the connection pad 23 are connected via a conductor portion (not shown) formed on the semiconductor substrate 21.

The side of the head chip 20 on which the heating resistor 22 is formed is laminated on the nozzle sheet 13 via the barrier layer 12 (corresponding to the liquid chamber forming member in the present invention). The barrier layer 12 is for forming the side wall of the ink liquid chamber 14 and is made of, for example, a photosensitive cyclized rubber resist or an exposure-curing dry film resist, and the heating resistance of the semiconductor substrate 21 of the head chip 20. After the body 22 is stacked on the entire surface, unnecessary portions are removed by a photolithography process.
Note that the distance between the head chip 20 and the nozzle sheet 13 is fixed by the particle spacer 17 (corresponding to the spacer in the present invention).

In FIG. 2, the plan view shows one heating resistor 22 and the barrier layer 12 provided around the heating resistor 22. The barrier layer 12 is formed in a substantially concave shape when viewed in plan so as to surround the vicinity of the three sides of the heating resistor 22.
In addition, particle spacers 17 are disposed at both ends of the semiconductor substrate 21 (outside the barrier layer 12).

  Furthermore, the nozzle sheet 13 is formed with a plurality of nozzles 13a, and is formed by, for example, nickel electroforming technology so that the position of the nozzle 13a matches the position of the heating resistor 22, that is, the nozzle 13a. More specifically, the center axis of the nozzle 13a and the center of the heating resistor 22 coincide with each other so as to face the heating resistor 22 (see the plan view of FIG. 2). The barrier layer 12 is bonded.

  The ink liquid chamber 14 is composed of the semiconductor substrate 21, the barrier layer 12, and the nozzle sheet 13 so as to surround the heating resistor 22. The ink liquid chamber 14 is filled with ink to be ejected, and ink is applied when ink is ejected. It becomes a pressure chamber. The surface of the semiconductor substrate 21 on which the heat generating resistor 22 is formed constitutes the bottom wall of the ink liquid chamber 14, and the portion of the barrier layer 12 surrounding the heat generating resistor 22 in a substantially concave shape forms the side wall of the ink liquid chamber 14. The nozzle sheet 13 constitutes the top wall of the ink liquid chamber 14. The ink liquid chamber 14 communicates with a flow path 16 formed by a gap between the head module 11 and the semiconductor substrate 21 as shown in the plan view of FIG.

  The one head chip 20 is usually provided with heating resistors 22 in units of 100, and each of the heating resistors 22 is uniquely selected by a command from a control unit (not shown) of the printer. Ink in the ink liquid chamber 14 corresponding to the heating resistor 22 can be ejected from the nozzle 13 a facing the ink liquid chamber 14.

  That is, when the ink liquid chamber 14 is filled with ink, the heating resistor 22 is rapidly heated by passing a pulse current through the heating resistor 22 for a short time, for example, 1 to 3 μsec. As a result, a gas-phase ink bubble is generated at a portion in contact with the heating resistor 22, and a certain volume of ink is pushed away (the ink boils) due to the expansion of the ink bubble. As a result, a volume of ink equivalent to the pushed ink in the portion in contact with the nozzle 13a is ejected from the nozzle 13a as an ink droplet. The droplets are landed on the photographic paper to form dots (pixels).

Next, a more detailed structure and manufacturing process of the head module 10 will be described.
FIG. 3 is a plan view and a front view showing one head module 10. The head module 10 according to this embodiment includes four head chips 20 arranged inside, a module frame 11, a nozzle sheet 13, and a buffer tank 15.

  FIG. 4 is a plan view showing the nozzle sheet 13 and the module frame 11 in an exploded manner. The module frame 11 is formed in a substantially rectangular shape when viewed in a plan view, and has engaging portions 11a cut out in a substantially L shape on both left and right ends. As is apparent from FIG. 4, when the nozzle sheet 13 and the module frame 11 are overlapped, the shapes of both are formed so as to substantially overlap except for the wiring pattern portion 13 b of the nozzle sheet 13.

  The wiring pattern portion 13b is a portion of the nozzle sheet 13 that does not overlap the module frame 11, and is formed by forming a so-called sandwich structure in which a copper foil is sandwiched from both sides with polyimide or the like. As shown in FIG. 12 to be described later, the wiring pattern portion 13b is wired up to an area in each head chip arrangement hole 11b, and when the head chip 20 is arranged in the head chip arrangement hole 11b, the head chip is arranged. It is formed so that electrical connection with 20 is possible.

  The module frame 11 is formed of alumina ceramic, invar steel, stainless steel, or the like having a thickness of about 0.5 mm. In this embodiment, substantially rectangular head chip arrangement holes 11b are formed at four locations. Has been. The head chip placement hole 11b has a hole shape slightly larger than the outer shape of the head chip 20, so that the head chip 20 can be completely placed inside.

  FIG. 5 is a plan view and a front view showing a state in which the module frame 11 is disposed on the nozzle sheet 13. In this embodiment, it joins by thermocompression bonding with hot press. Thereby, the module frame 11 substantially overlaps the area of the nozzle sheet 13 excluding the wiring pattern portion 13b. In other words, only the region where the wiring pattern portion 13 b of the nozzle sheet 13 is formed does not overlap the region of the module frame 11. Further, the nozzle sheet 13 located below the head chip arrangement hole 11b can be seen.

  The module frame 11 and the nozzle sheet 13 are joined at the highest temperature (for example, about 150 ° C.) in the manufacturing process of the head module 10 and the liquid ejection head 1. When the module frame 11 and the nozzle sheet 13 are compared, the nozzle sheet 13 has a larger linear expansion coefficient (easily expands and contracts due to a temperature change). Below this temperature, the nozzle sheet 13 is stretched by the module frame 11. That is, the expansion and contraction due to the temperature change of the nozzle sheet 13 is governed by the module frame 11 after the nozzle sheet 13 and the module frame 11 are joined.

  Therefore, in order to ensure the rigidity of the module frame 11 as much as possible, it is preferable that the opening area of the head chip arrangement hole 11b of the module frame 11 is minimized. That is, after the placement of the head chip 20 in the head chip placement hole 11b, a flow path 16 is formed between the common liquid flow path 15a in the buffer tank 15 described later and the ink liquid chamber 14, and the nozzle sheet 13 is also formed. It is preferable to set the opening area to a minimum, on the condition that the positional deviation when the head chip 20 is arranged in accordance with the nozzle 13a formed in the above can be absorbed.

  Subsequently, a nozzle 13a row in which a number of nozzles 13a opposite to the number of heating resistors 22 in one head chip 20 are aligned in one direction with respect to the nozzle sheet 13 in the area of the head chip arrangement hole 11b. Form. FIG. 6 is a plan view showing a state in which the nozzle 13a row is formed on the nozzle sheet 13 in the head chip arrangement hole 11b.

The nozzle 13a is formed by an excimer laser. Further, since the nozzle 13a formed by the laser beam is tapered, the laser beam is irradiated from the module frame 11 side to form the nozzle 13a. As a result, the nozzle 13a becomes a hole having a taper so that the opening diameter gradually decreases as it approaches the ink ejection surface (the outer surface of the nozzle sheet 13).
Further, the pitch between the nozzles 13a of the nozzle 13a row formed in each head chip arrangement hole 11b is the same as the arrangement pitch of the heating resistors 22 of the head chip 20 (in the case of the head module 10 having a resolution of 600 dpi, And about 42.3 μm).

  Furthermore, as shown in FIG. 6, the nozzle 13a row in each head chip arrangement hole 11b is considered to be a line connecting the nozzles 13a row in each head chip arrangement hole 11b (a line passing through the center of each nozzle 13a). Sometimes, the line is formed on the center line side of the module frame 11 drawn parallel to the longitudinal direction of the module frame 11. Further, assuming that each head chip arrangement hole 11b is “N”, “N + 1”, “N + 2”, “N + 3” in order from the left side, the nozzles in the “N” -th and “N + 2” -th head chip arrangement holes 11b. The 13a row is formed so as to be aligned on a straight line parallel to the center line. The same applies to the “N + 1” th and “N + 3” th.

Therefore, the nozzles 13a in the adjacent head chip arrangement holes 11b, for example, the nozzles 13a in the “N” th and “N + 1” th head chip arrangement holes 11b are on two straight lines parallel to the center line. Align.
In this embodiment, four head chip arrangement holes 11b are formed for one module frame 11. However, even when more head chip arrangement holes 11b are formed than in this embodiment, the above relationship is satisfied. Like that.

  Next, as shown in FIG. 7, the head chip 20 in which the barrier layer 12 is laminated is arranged and fixed in each head chip arrangement hole 11b. Here, the head chip 20 is thermocompression bonded while being aligned using a chip mounter. Further, in this case, thermocompression bonding is performed with an accuracy of, for example, about ± 1 μm so that the nozzle 13a is positioned directly below the heating resistor 22 of the head chip 20.

FIG. 8 is a side cross-sectional view illustrating a method for fixing the barrier layer 12 and the nozzle sheet 13.
As shown in FIG. 8, the particle spacers 17 are disposed on both ends of the semiconductor substrate 21 (outside the barrier layer 12) (first step). Note that the barrier layer 12 is already formed on the semiconductor substrate 21 before the particle spacer 17 is disposed.
The particle spacer 17 is made of true spherical plastic fine particles having heat resistance, and has a uniform particle diameter of 10 μm, whereas the thickness of the barrier layer 12 is 11 μm. In addition to hard plastic, silicon dioxide or the like may be used.

The particle spacer 17 will be described in more detail. The CV value (an index indicating the accuracy of the particle diameter, standard deviation / average particle diameter) is 6% or less, and the K value at 20 ° C. (when 10% of the particle diameter is displaced). Thermally very stable microspheres having a compression elastic modulus) of 250 to 700 kgf / mm ² , a recovery rate of 30 to 80% and almost no weight loss in the temperature range from 200 to 800 ° C. are suitable. .
Specifically, after conducting electroless Ni plating on the surface of plastic fine particles, conductive fine particles (for example, trade name “Micropearl” from Sekisui Chemical Co., Ltd.) or the like with Au substitution plating, high purity Resin-coated composites composed of silicon alkoxide and based on fine particles with a spherical shape and a very sharp particle size distribution (for example, Ube-Nitto Kasei Co., Ltd., trade name “HI-PRECICA”), monodispersed silica fine particles There are particles.

  Further, the particle spacer 17 of the present embodiment is in a paste form and can be applied to the lower surface of the semiconductor substrate 21. The coating method may be mechanical coating or an additional method using a printing technique. The paste is preferably a resin that is cured by heat, UV, or the like so as not to move to another place after assembly.

After such a particle spacer 17 is applied, the barrier layer 12 is thermocompression bonded to the nozzle sheet 13 on the jig as indicated by an arrow (the head chip 20 and the nozzle sheet 13 are thermocompression bonded via the barrier layer 12. (Second step). At this time, since the particle diameter of the particle spacer 17 is uniform, strong against compression, and thermally stable, even if the pressure-bonding force fluctuates, the distance between the head chip 20 and the nozzle sheet 13 is , Depending on the particle diameter of the particle spacer 17. Therefore, the head chip 20 is accurately positioned with respect to the nozzle sheet 13.
The particle spacer 17 may be provided not on the semiconductor chip 21 side of the head chip 20 as described above but on the nozzle sheet 13 side.

  As described above, when the head chip 20 on which the barrier layer 12 is formed is arranged in the head chip arrangement hole 11b and the nozzle sheet 13 and the head chip 20 are bonded with high accuracy, the head chip 20 side of the nozzle sheet 13 is arranged. The ink liquid chamber 14 is formed as described above by the surface, the barrier layer 12, and the surface on which the heating resistor 22 of the head chip 20 is formed.

  Subsequently, the connection pads 23 provided on the head chip 20 side are electrically connected to the electrodes 13c (plated layer having the outermost surface formed of gold) of the wiring pattern portion 13b on the nozzle sheet 13 side. FIG. 9 is a plan view showing the arrangement of the connection pads 23 on the head chip 20 side. In FIG. 9, the nozzle 13a and the connection pad 23 are shown by solid lines. As shown in FIG. 9, one head chip 20 is provided with a plurality of connection pads 23 in advance along the longitudinal direction of the head chip 20. In addition, in FIG. 2 mentioned above, the positional relationship between the connection pad 23 and the wiring pattern portion 13b of the nozzle sheet 13 is illustrated in a sectional view.

FIG. 10 is a side cross-sectional view illustrating a method of connecting the connection pads 23 of the head chip 20 and the electrodes 13c of the wiring pattern portion 13b with the nozzle sheet 13.
As shown in FIGS. 2 and 10, an electrode 13 c is provided at the tip of the wiring pattern portion 13 b in the nozzle sheet 13 in the region of the head chip arrangement hole 11 b of the module frame 11. Further, an opening 13 d is formed around the electrode 13 c of the nozzle sheet 13.

  Then, as shown in FIG. 10, a pin-like vibration tool T is inserted from the opening 13d on the surface opposite to the surface to which the module frame 11 of the nozzle sheet 13 is bonded. By applying sonic vibration, the connection pad 23 and the electrode 13c of the wiring pattern portion 13b are metal-bonded by ultrasonic waves. Then, after joining, the opening 13d is sealed with resin (see FIG. 2). As shown in FIG. 2, after sealing, the resin is made to substantially coincide with the surface of the nozzle sheet 13 (so as not to rise from the surface of the nozzle sheet 13).

  As shown in FIG. 2, a printed circuit board 31 is provided on the wiring pattern portion 13b of the nozzle sheet 13, and a conductor 31a is formed on the surface of the printed circuit board 31 that faces the wiring pattern portion 13b. ing. And this conductor 31a and the wiring of the wiring pattern part 13b are electrically connected. Thereby, the heating resistor 22 and the printed circuit board 31 (the heating resistor 22 and the connection pad 23, the connection pad 23 and the wiring pattern portion 13b, and the wiring pattern portion 13b and the printed circuit board 31) are electrically connected. Become.

  Next, the buffer tank 15 is attached from the module frame 11 side. FIG. 11 is a plan view and a front view showing a state in which the buffer tank 15 is attached. FIG. 12 is a side sectional view showing a state in which the buffer tank 15 is attached.

  One buffer tank 15 is provided for one head module 10. As shown in FIG. 11, the buffer tank 15 has a shape slightly smaller than the module frame 11 when viewed in a plan view, but is substantially similar to the module frame 11. Further, as shown in FIG. 12, a common liquid flow path 15 a that is a cavity is formed inside the buffer tank 15. In particular, the buffer tank 15 of the present embodiment is formed such that the lower surface side (bonding surface side with the module frame 11) is opened, the side wall and the top wall are formed with the same thickness, and the cross section is substantially reverse concave. As a result, the common liquid channel 15a is formed.

As shown in FIG. 12, the edge of the lower surface side of the buffer tank 15 and the module frame 11 are bonded together with an adhesive. When the buffer tank 15 is mounted on the module frame 11, as shown in FIG. 11, all the head chip arrangement holes 11b are covered. Further, as shown in FIG. 12, the common liquid flow path 15a of the buffer tank 15 and the ink liquid chamber 14 of each head chip 20 are connected via the flow path 16 between the head chip arrangement hole 11b and the head chip 20. Communicated. As a result, the buffer tank 15 forms a common liquid channel 15 a for all the head chips 20 in the head module 10.
Further, as shown in FIG. 11, a hole 15b is formed in the top wall of the buffer tank 15, and ink is supplied from the ink tank (not shown) into the common liquid flow path 15a through the hole 15b. Is done.

  Here, as shown in FIG. 12, the inner edge (A portion in FIG. 12) on the lower surface side of the buffer tank 15 is formed in a convex section, and this convex section is in contact with the module frame 11. . Then, an adhesive is put on the outside of this convex part (the part which is a step with respect to the convex part; B part in FIG. 12) and bonded. Thereby, both can be easily bonded, and the shape of the buffer tank 15 can be simplified. Further, on the lower surface side of the buffer tank 15, the adhesive portion enters the inside (on the side of the common liquid flow path 15 a or the head chip 20) due to the convex portion of the inner edge contacting the module frame 11. Can be prevented.

  The head module 10 is completed as described above. In the head module 10 of the present embodiment, the gap between the nozzle sheet 13 and the head chip 20 in the head chip arrangement hole 11 b is held with a uniform particle diameter of the particle spacer 17. Therefore, the positional accuracy between the head chip 20 and the nozzle sheet 13 can be easily ensured, and the assembly accuracy can be improved, and further the ink ejection performance can be improved.

Furthermore, in the present embodiment, one liquid discharge head 1 is formed by using a plurality of the head modules 10.
FIG. 13 is a plan view and a front view showing a state in which the head modules 10 are arranged side by side. In FIG. 13, a plurality of head modules 10 are illustrated in a plan view, but a state in which one head module 10 is disposed is illustrated in a front view.

  In the present embodiment, as shown in the plan view of FIG. 13, the four head modules 10 are aligned in series on the base jig C. In this case, it arrange | positions so that the engaging parts 11a of the both ends of each head module 10 may engage, ie, the parts cut out in the substantially L shape mutually connect. By aligning the four head modules 10 in a row in this way, a line head corresponding to A4 is formed. Furthermore, four rows of the head modules (consisting of four head modules 10) are arranged in four rows (in the plan view of FIG. 13, three rows of head modules are arranged, and the bottom row of head modules 10 rows). Here, a state in which one head module 10 is placed on the base jig C is illustrated), and a color line head corresponding to four colors (color) of Y, M, C, and K is formed.

  The two head modules 10 connected in series are respectively referred to as a head module “N” (left side) and a head module “N + 1” (right side), and the four head chips 20 in the head modules “N” and “N + 1”. Are 20A, 20B, 20C, and 20D in order from the left side, the head chip 20D of the head module “N” and the head chip 20A of the head module “N + 1” include at least one nozzle 13a. It arrange | positions so that it may overlap in a row direction. That is, among the head chips 20D of the head module “N”, the nozzle 13a that is closest to the head module “N + 1” is more than the nozzle that is closest to the head module “N” among the head chips 20A of the head module “N + 1”. Are also arranged on the right side.

  Then, as described above, after four rows of four head modules 10 are arranged in a row, the head frame 2 is arranged from above. The head frame 2 has four head module arrangement holes 2a formed on a highly rigid metal plate or the like so that four head modules 10 arranged in series can be arranged inside. That is, with respect to the four head modules 10 arranged as shown in FIG. 13, when the head frame 2 is arranged from the upper side, the head module arrangement holes 2a are arranged so that the four head modules 10 enter inside. Is formed.

  When the head frame 2 is thus arranged, the state shown in FIG. 1 is obtained, and the liquid discharge head 1 is formed. 1, the buffer tank 15 of each head module 10 does not come into contact with the head module placement hole 2a, but the module frame 11 and the head frame 2 of each head module 10 are not in contact with each other. The head frame 2 and each head module 10 are fixed by contacting and adhering both.

  As shown in the side view in the direction of the arrow X in FIG. 1, before the head frame 2 is bonded to the head module 10, the printed circuit board 3 is bonded to the lower surface side of the head frame 2 in a separate process. . The printed circuit board 3 is formed so as to avoid the head module arrangement hole 2a of the head frame 2 when viewed in a plan view. 1, the printed circuit board 3 is disposed between the module frames 11 of the head modules 10 without contacting the module frames 11 of the head modules 10.

Although one embodiment of the present invention has been described above, the present invention is not limited to the above-described embodiment, and various modifications such as the following are possible.
(1) Four head chip placement holes 11b are formed in the module frame 11, so that four head chips 20 are mounted on one head module 10. However, the present invention is not limited thereto, and any number of head chips 20 may be mounted on one head module 10, and the head chips 20 may be arranged on the nozzle sheet 13 without using the module frame 11. .

  (2) In the case where the liquid discharge head 1 is formed as a line head, in this embodiment, four rows of head modules 10 in which four head modules 10 are connected in series are provided. The number of head modules 10 of one liquid discharge head 1 can be increased or decreased according to the use of the discharge head 1 and the number of colors.

FIG. 2 is a plan view showing an embodiment of a liquid discharge head according to the present invention and a side view (cross-sectional view) in the direction of the arrow in the X direction. FIG. 4 is a cross-sectional view showing a head chip mounted in a liquid discharge head and a configuration around the head chip and a plan view seen from the bottom surface. It is the top view and front view which show one head module. It is a top view which decomposes | disassembles and shows a nozzle sheet and a module frame. It is the top view and front view which show the state which has arrange | positioned the module frame on the nozzle sheet | seat. It is a top view which shows the state by which the nozzle row | line was formed in the nozzle sheet | seat in a head chip arrangement | positioning hole. It is a figure which shows the state which has arrange | positioned and fixed the head chip which laminated | stacked the barrier layer in each head chip arrangement | positioning hole. It is sectional drawing of the side surface explaining the fixing method of a barrier layer and a nozzle sheet. It is a top view which shows arrangement | positioning of the connection pad by the side of a head chip. It is side surface sectional drawing explaining the connection method of the connection pad of a head chip, and the electrode of the wiring pattern part with a nozzle sheet. It is the top view and side view which show the state which attached the buffer tank to the head module. It is sectional drawing of the side surface which shows the state in which the buffer tank was attached. It is the top view and front view which show the state which arranged the head module side by side.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Liquid discharge head 2 Head frame 2a Head module arrangement | positioning hole 3 Printed circuit board 10 Head module 11 Module frame 11a Engagement part 11b Head chip arrangement | positioning hole 12 Barrier layer 13 Nozzle sheet 13a Nozzle 13b Wiring pattern part 13c Electrode 13d Opening part 14 Ink liquid Chamber 15 Buffer tank 15a Common liquid flow path 15b Hole 16 Flow path 17 Particle spacer 20 Head chip 21 Semiconductor substrate 22 Heating resistor 23 Connection pad 31 Printed circuit board 31a Conductor C Base jig T Excitation tool

Claims (7)

A head chip in which a plurality of energy generating elements are arranged in one direction at regular intervals;
A nozzle sheet on which nozzles for discharging droplets are formed;
A liquid chamber forming member that is laminated between the formation surface of the energy generating element of the head chip and the nozzle sheet, and that forms a liquid chamber between each of the energy generating elements and each of the nozzles;
A head module for discharging the liquid in the liquid chamber from the nozzle by the energy generating element;
A head module, wherein a spacer made of particles having a diameter equal to or less than the thickness of the liquid chamber forming member is disposed between the head chip and the nozzle sheet. The head module according to claim 1,
The said spacer is arrange | positioned at the both ends of the said head chip. The head module characterized by the above-mentioned. The head module according to claim 1,
The head module is characterized in that the spacer is made of spherical plastic particles. Multiple head modules;
A head module arrangement hole for arranging a plurality of the head modules arranged in series inside is formed, and each of the head modules arranged in the head module arrangement hole is attached to a head frame. ,
The head module is
A head chip in which a plurality of energy generating elements are arranged in one direction at regular intervals;
A nozzle sheet on which nozzles for discharging droplets are formed;
A liquid chamber forming member that is stacked between the formation surface of the energy generating element of the head chip and the nozzle sheet, and forms a liquid chamber between each of the energy generating elements and each of the nozzles;
A module frame that supports the nozzle sheet by being bonded to one surface of the nozzle sheet and has a head chip placement hole for placing the head chip therein, and
A liquid discharge head for discharging the liquid in the liquid chamber from the nozzle by the energy generating element;
When the head chip is arranged in the head chip arrangement hole, a spacer made of particles having a diameter equal to or less than the thickness of the liquid chamber forming member is arranged between the head chip and the nozzle sheet. ,
The module frame includes an engagement portion for engaging each other when the other module frames are arranged in series in the arrangement direction of the nozzles,
The engagement portions of the plurality of head modules are engaged with each other, and the plurality of head modules are arranged in series, and are arranged in the head module arrangement hole of the head frame. Liquid discharge head. A head chip in which a plurality of energy generating elements are arranged in one direction at regular intervals;
A nozzle sheet on which nozzles for discharging droplets are formed;
A liquid chamber forming member that is stacked between the formation surface of the energy generating element of the head chip and the nozzle sheet, and forms a liquid chamber between each of the energy generating elements and each of the nozzles;
A module frame having a head chip arrangement hole for supporting the nozzle sheet by being bonded to one surface of the nozzle sheet and arranging the head chip therein, and
A liquid ejection device that ejects the liquid in the liquid chamber from the nozzle by the energy generating element,
When the head chip is arranged in the head chip arrangement hole, a spacer made of particles having a diameter equal to or smaller than the thickness of the liquid chamber forming member is arranged between the head chip and the nozzle sheet. A liquid discharge apparatus comprising: a liquid discharge head in which a plurality of head modules are arranged in series. A head chip in which a plurality of energy generating elements are arranged in one direction at regular intervals;
A nozzle sheet on which nozzles for discharging droplets are formed;
A liquid chamber forming member that is laminated between the formation surface of the energy generating element of the head chip and the nozzle sheet, and that forms a liquid chamber between each of the energy generating elements and each of the nozzles;
A method of manufacturing a head module that discharges liquid in the liquid chamber from the nozzle by the energy generating element,
A first step of arranging a spacer made of particles having a diameter equal to or less than the thickness of the liquid chamber forming member on at least one side of the head chip or the nozzle sheet;
And a second step of thermocompression bonding the head chip and the nozzle sheet via the liquid chamber forming member. Multiple head modules;
A head module arrangement hole for arranging a plurality of the head modules arranged in series inside is formed, and each of the head modules arranged in the head module arrangement hole is attached to a head frame. ,
The head module is
A head chip in which a plurality of energy generating elements are arranged in one direction at regular intervals;
A nozzle sheet on which nozzles for discharging droplets are formed;
A liquid chamber forming member that is stacked between the formation surface of the energy generating element of the head chip and the nozzle sheet, and forms a liquid chamber between each of the energy generating elements and each of the nozzles;
A module frame that supports the nozzle sheet by being bonded to one surface of the nozzle sheet and has a head chip placement hole for placing the head chip therein, and
A method of manufacturing a liquid discharge head for discharging the liquid in the liquid chamber from the nozzle by the energy generating element,
A first step of arranging a spacer made of particles having a diameter equal to or less than the thickness of the liquid chamber forming member on at least one side of the head chip or the nozzle sheet;
Forming the head module by a step including a second step of thermocompression bonding the head chip and the nozzle sheet via the liquid chamber forming member;
In a state where a plurality of the formed head modules are arranged in series, the plurality of the head modules are arranged in the head module arrangement holes of the head frame, and the module frames and the head frames are bonded together. A method of manufacturing a liquid discharge head, comprising: a step.