JP4196809B2 - Head module, liquid discharge head, liquid discharge apparatus, and liquid discharge head manufacturing method - Google Patents

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 method for manufacturing the liquid discharge head, and a liquid discharge apparatus. More specifically, the present invention relates to a technology for forming a head module and a liquid ejection head that improve the cooling effect and prevent deterioration of liquid such as ink by configuring the liquid ejection head using a head module including a buffer tank. is there.

Conventionally, an ink jet printer has been known as an example of a liquid ejecting apparatus, and various techniques have been disclosed for a printer head of an ink jet printer.
For example, Patent Document 1 and Patent Document 2 disclose a head assembly technique in which a line head is formed by a plurality of head chips.
JP 2002-127427 A JP 2003-25579 A

  In the techniques of Patent Literature 1 and Patent Literature 2 described above, a large number of nozzles (ink ejection ports) are provided in one nozzle forming member made of nickel formed by electroforming. A plurality of head chips are attached to the one nozzle forming member. Further, a head frame in which holes are formed so as to surround the attached head chip is bonded to the nozzle sheet, and the nozzle sheet is supported.

  Note that heating resistors are arranged on the head chip, and the head chip is attached to the nozzle sheet so that each heating resistor corresponds to each nozzle. An ink liquid chamber is provided between the heating resistor and the nozzle.

Further, on the head frame, there is provided a flow path plate that enters into a hole surrounding the head chip and joins the head chip. The flow path plate has a common flow path that communicates with all the ink liquid chambers.
In the above configuration, ink is filled from the ink tank into each ink chamber via the common flow path of the flow path plate. The ink in the ink liquid chamber is heated by the heating resistor, and the ink is ejected from the nozzles by the energy at the time of heating.

There is also known a unit-type technique in which a head assembly including a plurality of head chips is used as one head module, and a head assembly is configured by combining a plurality of the head modules (see, for example, Patent Document 3).
Japanese Patent Laid-Open No. 7-251505

However, in the techniques of Patent Document 1 and Patent Document 2 described above, when the print characteristics test of the head assembly is performed, the entire head assembly must be assembled before the test. Therefore, if even one of the head chips is defective, there is a problem that the entire head assembly becomes unusable.
Further, even if the head assembly is partially broken, the whole is replaced, and there is a problem that the cost of repair becomes high.

Furthermore, since the techniques of Patent Document 1 and Patent Document 2 have a structure in which a flow path plate is fitted in a hole in which the head chip is disposed, the amount of ink stored around the head chip is small, and the head chip In addition, there is a problem that the surrounding ink becomes high temperature.
Under such a high temperature environment, the performance, life and failure of the head chip having the semiconductor portion are adversely affected, and the ink in the common flow path may be altered.

  For this reason, a cooling system, such as forcibly circulating the ink, is provided so that the head chip and ink do not reach a high temperature, and when the ink is ejected, the cooling system is operated, thereby degrading the head chip and changing the quality of the ink. There was a need to prevent.

  Furthermore, in Patent Document 3, the unit type is used to cope with a partial failure of the head assembly, but this time the ink flow path is divided for each unit, and the ink is forced by the cooling system. In order to circulate automatically, it is necessary to connect the ink inlet and outlet of the units one by one with a flow path.

  For this reason, the flow path is repeatedly bent in the vertical direction and the horizontal direction, resulting in a complicated flow path. In such a flow path, since the flow path resistance becomes very large, the smooth circulation of the ink is hindered, and sufficient cooling performance cannot be obtained.

  Moreover, it is preferable that the nozzle formation surface is the same surface among the plurality of units. For example, in the case where ink is ejected accurately and perpendicularly to the ink landing surface of the recording medium, there is no significant effect on the print quality even if there is a slight displacement in the nozzle formation surface between the multiple units. For example, when the ink ejection direction is not completely perpendicular to the ink landing surface of the recording medium, the ink landing position changes if the positions of the nozzle formation surfaces do not match between the plurality of units. .

  In particular, the applicant of the present application has disclosed the undisclosed prior application technologies of Japanese Patent Application 2003-037343, Japanese Patent Application 2002-360408, Japanese Patent Application 2003-55236, and the like in a plurality of directions. 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 a technique for actively changing the discharge direction of the liquid droplets discharged from the nozzle is used, high accuracy is required for the position accuracy of the nozzle formation surface. However, Patent Document 3 does not disclose how to ensure the positional accuracy of the nozzle formation surface among a plurality of units.

  Therefore, the problem to be solved by the present invention is that the cooling effect of the head chip and ink can be obtained without providing a special cooling system, and the positional accuracy of the nozzle forming surface between the head chips is made high, It is to form a head that can also be used for a line head.

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 A liquid chamber forming member for forming a liquid chamber between each energy generating element and each nozzle, and one of the nozzle sheets. A module frame in which a head chip placement hole for supporting the nozzle sheet and placing the head chip therein is formed, and a bonding surface of the module frame to the nozzle sheet; A buffer tank that is stacked on the opposite surface and forms a common liquid channel that communicates with all the liquid chambers of the head chip, and The energy generating element, a head module for discharging the liquid in the liquid chamber from said nozzle, said buffer tank, with the lower surface side is opened to be stacked on the module frame, the stacking direction of the cross-section side walls and top wall So that the common liquid flow path is formed, and the inner surface of the side wall of the buffer tank is such that the upper surface of the head chip is in contact with the liquid in the common liquid flow path. in the head chip made and shape never writing arranged fits to the head chip disposed within the bore, the outer surface of the side wall of the buffer tank, the head modules that have been made with the shape along the outer shape of the module frame It is.

According to a fourth aspect of the present invention, there is provided a liquid discharge head having a head module arrangement hole for arranging a plurality of the head modules of the first aspect arranged in series therein, and the arrangement in the head module arrangement hole. Each of the head modules and the head frame bonded together, and the module frame has a flange portion that partially or entirely protrudes from the outer surface of the buffer tank, and each of the flange portions of each module frame. And the head frame are bonded together, and a plurality of the head modules are arranged in the head module arrangement hole.
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 module has the nozzle sheet and the module frame bonded together. Further, a head chip arrangement hole is formed in the module frame. And the buffer tank is formed so that the lower surface side stacked on the module frame is opened and the cross section in the stacking direction becomes a reverse concave shape by the side wall and the top wall, thereby forming a common liquid flow path, The inner surface of the side wall of the buffer tank is shaped so as not to fit into the head chip placement hole in which the head chip is placed so that the upper surface of the head chip is in contact with the liquid in the common liquid flow path. The outer surface of the side wall is shaped along the outer shape of the module frame.

In this state, the buffer tank is laminated on the surface of the module frame opposite to the surface to be bonded to the nozzle sheet. A common liquid channel is formed in the buffer tank, and the common liquid channel communicates with the liquid chamber of each head chip.
Furthermore, in the invention of claim 4 or claim 5, the liquid ejection head is formed by connecting the head modules of claim 1 in series.

  As the energy generating element of the present invention, a heating resistor such as a heater, a piezoelectric element such as a piezo element, MEMS, or the like can be used. In the following embodiment, the heating resistor 22 corresponds. In addition, the liquid chamber forming member of the present invention corresponds to the barrier layer 12 in the embodiment. Furthermore, in the embodiment, 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.

  According to the head module of the present invention, since the amount of liquid temporarily stored in the buffer tank can be increased, the heat capacity in the vicinity of the head chip is increased and the cooling effect of the head chip can be improved. Further, since the liquid in the buffer tank does not reach a high temperature, it is possible to prevent deterioration of the liquid such as ink without always operating a cooling system for forcibly circulating the liquid.

  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.

  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.

  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.

  As shown in FIG. 3, the outer surface of the buffer tank 15 has a shape that follows the outer shape of the module frame 11 and is substantially similar to the outer shape of the module frame 11. And the part which protruded entirely from the outer surface of the buffer tank 15 of the module frame 11 is the collar part 11c. Further, the buffer tank 15 is merely laminated on the module frame 11, and the inner surface of the buffer tank 15 is not fitted into the head chip arrangement hole 11b.

  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, 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. . 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.

  Thus, 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, the surface of the nozzle sheet 13 on the head chip 20 side, The ink liquid chamber 14 is formed by the barrier layer 12 and the surface of the head chip 20 on which the heating resistor 22 is formed as described above.

  Subsequently, the connection pads 23 provided on the head chip 20 side are electrically connected to the electrodes 13c (plating layer formed of gold on the outermost surface) of the wiring pattern portion 13b on the nozzle sheet 13 side. FIG. 8 is a plan view showing the arrangement of the connection pads 23 on the head chip 20 side. In FIG. 8, the nozzle 13a and the connection pad 23 are shown by solid lines. As shown in FIG. 8, 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.

  As shown in FIG. 2, an electrode 13 c is provided at the tip of the wiring pattern portion 13 b in the nozzle sheet 13 in the area 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, for example, a pin-like vibration tool is inserted from the opening 13d, and ultrasonic vibration is applied to the vibration tool, so that the connection pad 23 and the electrode 13c of the wiring pattern portion 13b are joined by ultrasonic waves. To do. Then, after bonding, the opening 13d is sealed with resin, and 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. 9 is a plan view and a front view showing a state in which the buffer tank 15 is attached. FIG. 10 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. 9, the buffer tank 15 has a shape slightly smaller than the module frame 11 when viewed in a plan view, and the module frame 11 has a flange portion 11c. It is almost similar. Furthermore, as shown in FIG. 10, a common liquid flow path 15 a that is a cavity is formed inside the buffer tank 15. In other words, the buffer tank 15 is formed so that the lower surface side (the surface to be bonded to the module frame 11) is opened, the side wall and the top wall are formed to have the same thickness, and the cross section is substantially reverse concave. Thus, the common liquid channel 15a is formed.

As shown in FIG. 10, the edge on 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. 9, all the head chip arrangement holes 11b are covered. Further, as shown in FIG. 10, the common liquid flow path 15 a of the buffer tank 15 and the ink liquid chamber 14 of each head chip 20 are connected via a flow path 16 between the head chip placement hole 11 b 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. 9, 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 channel 15a through the hole 15b. Is done.

  Here, as shown in FIG. 10, the inner edge (A portion in FIG. 10) 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 outer side of this convex part (the part which is a step with respect to the convex part, part B in FIG. 10) and bonded. Thus, the inner surface of the buffer tank 15 does not fit into the head chip arrangement hole 11b, and the upper surface of the head chip 20 is all in contact with the ink in the common liquid channel 15a. Further, the module frame 11 and the buffer tank 15 can be easily bonded, and the shape of the buffer tank 15 can be simplified.

  The head module 10 is completed as described above. In the head module 10 of the present embodiment, the buffer tank 15 has a substantially similar shape slightly smaller than the module frame 11 when viewed in a plan view (see FIG. 9). That is, the maximum size is ensured while the module frame 11 has the flange portion 11c. Further, when viewed in a cross-sectional view (see FIG. 10), the inner surface of the buffer tank 15 has a substantially inverted concave shape that does not fit into the head chip placement hole 11b. That is, the entire upper surface of the head chip 20 is used as the bottom wall of the common liquid channel 15a.

  Therefore, the amount of ink in the common liquid channel 15a is greatly increased, and the head chip 20 can be efficiently cooled. That is, in order to eject ink from the nozzles 13a, the heating resistor 22 is rapidly heated by supplying a pulse current. However, the higher the temperature environment, the worse the performance, life, and failure of the head chip 20. Therefore, it is necessary to cool and protect the head chip 20 at all times. However, since the heat capacity increases as the ink amount increases and heat is radiated from the entire upper surface of the head chip 20, a cooling system that circulates the ink is operated. There is no need to let them. In addition, the quality of the ink in the common liquid channel 15a due to high temperature can be prevented, the ink can be stably supplied, and printing troubles such as ink smearing of printed matter can be reduced.

Furthermore, in the present embodiment, one liquid discharge head 1 is formed by using a plurality of the head modules 10.
FIG. 11 is a plan view and a front view showing a state in which the head modules 10 are arranged side by side. In FIG. 11, the plan view shows a plurality of head modules 10, but the front view shows a state in which one head module 10 is arranged.

  In the present embodiment, as shown in the plan view of FIG. 11, 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. 11, three rows of head modules 10 are arranged, and the head module 10 rows in the lowermost row are arranged. 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, four head modules 10 in one row are arranged in four rows, and then bonded to the head frame 2. 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, the head module arrangement hole 2a is formed so that the four head modules 10 arranged as shown in FIG.

FIG. 12 is an explanatory diagram showing a procedure for attaching the head module 10 into the head module placement hole 2 a of the head frame 2.
As shown in FIG. 12, the module frame 11 of the head module 10 has a flange 11 c that protrudes entirely from the outer surface of the buffer tank 15. The size of the head module placement hole 2 a is slightly larger than the buffer tank 15 and slightly smaller than the module frame 11.

  Therefore, when the head module 10 is inserted into the head module disposition hole 2a, the head module 10 is aligned by the flange portion 11c and can be positioned in the vertical direction. Accordingly, since the base jig C (see FIG. 11) only needs to be able to position the head module 10 in the left-right direction, it can be simplified from three-dimensional positioning to two-dimensional positioning. Note that the flange portion 11 c may partially protrude from the outer surface of the buffer tank 15.

  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 (see FIG. 12) of each head module 10. The part 11c) and the head frame 2 come into contact with each other, and the two are bonded together, so that the head frame 2 and each head module 10 are fixed.

  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 to this, and any number of head chips 20 may be mounted on one head module 10.

  (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. Here, when bonding with the head frame 2 cannot be considered as in the case of one head module 10, the flange 11c is not provided, and the planar shape of the buffer tank 15 is the same as the outer shape of the module frame 11. It can also be shaped.

FIG. 13 is a perspective view showing another embodiment of the head module 10.
The head module 10 shown in FIG. 13 is configured such that the buffer tank 15 and the module frame 11 have the same outer shape, whereby the buffer tank 15 is further enlarged. Therefore, the amount of ink temporarily stored inside can be further increased, and further improvement of the cooling effect can be expected.

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 a top view which shows arrangement | positioning of the connection pad by the side of a head chip. 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. It is explanatory drawing which shows the procedure which affixes a head module in the head module arrangement | positioning hole of a head frame. It is a perspective view which shows other embodiment of a head module.

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 11c Eaves part 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 20 Head chip 21 Semiconductor substrate 22 Heating resistor 23 Connection pad 31 Printed circuit board 31a Conductor C Base jig

Claims (6)

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 in which a head chip placement hole for supporting the nozzle sheet by being bonded to one surface of the nozzle sheet and placing the head chip therein is formed;
A buffer tank that is laminated on a surface opposite to the surface of the module frame that is bonded to the nozzle sheet, and that forms a common liquid channel that communicates with all the liquid chambers of the head chip,
A head module for discharging the liquid in the liquid chamber from the nozzle by the energy generating element;
The buffer tank is formed such that a lower surface side laminated on the module frame is opened and a cross section in a laminating direction is formed in a reverse concave shape by a side wall and a top wall, thereby forming the common liquid channel. ,
The inner surface of the side wall of the buffer tank has a shape that does not fit into the head chip arrangement hole in which the head chip is arranged so that the upper surface of the head chip is in contact with the liquid in the common liquid channel. And
The outer surface of the side wall of the buffer tank, the head modules that have been made with the shape along the outer shape of the module frame. The head module according to claim 1,
The buffer tank and the planar shape of the buffer tank as viewed from the stacking direction of the module frame, the outer shape and the head module Ru same shape der of the module frame. The head module according to claim 1,
The planar shape of the buffer tank is less similar shape der Ru head modules than the outline of the module frame as viewed from the stacking direction of the buffer tank and the module frame. 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 in which a head chip placement hole for supporting the nozzle sheet by being bonded to one surface of the nozzle sheet and placing the head chip therein is formed;
A buffer tank that is laminated on a surface opposite to the surface of the module frame that is bonded to the nozzle sheet, and that forms a common liquid channel that communicates with all the liquid chambers of the head chip,
A liquid discharge head for discharging the liquid in the liquid chamber from the nozzle by the energy generating element;
The buffer tank is formed such that a lower surface side laminated on the module frame is opened and a cross section in a laminating direction is formed in a reverse concave shape by a side wall and a top wall, thereby forming the common liquid channel. ,
The inner surface of the side wall of the buffer tank has a shape that does not fit into the head chip arrangement hole in which the head chip is arranged so that the upper surface of the head chip is in contact with the liquid in the common liquid channel. And
The outer surface of the side wall of the buffer tank is made with a shape along the outer shape of the module frame,
The module frame comprises a flange portion partially or totally protrudes from the outer surface of the buffer tank,
Each said module said is the head frame pasted with each said flange portion of the frame, the liquid ejection head a plurality of the head modules that are located in the head module positioned within the bore. 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 in which a head chip placement hole for supporting the nozzle sheet by being bonded to one surface of the nozzle sheet and placing the head chip therein is formed;
A buffer tank for forming a common liquid flow path that is laminated on a surface of the module frame opposite to the bonding surface with the nozzle sheet and that communicates with all the liquid chambers of the head chip, and
A liquid ejection device that ejects the liquid in the liquid chamber from the nozzle by the energy generating element,
The buffer tank is formed such that a lower surface side laminated on the module frame is opened and a cross section in a laminating direction is formed in a reverse concave shape by a side wall and a top wall, thereby forming the common liquid channel. ,
The inner surface of the side wall of the buffer tank has a shape that does not fit into the head chip arrangement hole in which the head chip is arranged so that the upper surface of the head chip is in contact with the liquid in the common liquid channel. And
The outer surface of the side wall of the buffer tank is made with a shape along the outer shape of the module frame,
Said head chip, the nozzle sheet, the liquid chamber forming member, said module frame, and the head module constituted by the buffer tank, the liquid ejection apparatus Ru comprising a liquid ejection head arranged in a plurality in series. 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 in which a head chip placement hole for supporting the nozzle sheet by being bonded to one surface of the nozzle sheet and placing the head chip therein is formed;
A buffer tank that is laminated on a surface opposite to the surface of the module frame that is bonded to the nozzle sheet, and that forms a common liquid channel that communicates with all the liquid chambers of the head chip,
A method of manufacturing a liquid discharge head for discharging the liquid in the liquid chamber from the nozzle by the energy generating element,
The buffer tank is formed such that a lower surface side laminated on the module frame is opened and a cross section in a laminating direction is formed in a reverse concave shape by a side wall and a top wall, thereby forming the common liquid channel. ,
The inner surface of the side wall of the buffer tank has a shape that does not fit into the head chip arrangement hole in which the head chip is arranged so that the upper surface of the head chip is in contact with the liquid in the common liquid channel. And
The outer surface of the side wall of the buffer tank has a shape along the outer shape of the module frame,
A first step of attaching the module frame to one surface of the nozzle sheet;
When the head chip is arranged in the area of the head chip arrangement hole, the nozzle is located at a position facing each energy generating element of the head chip in the nozzle sheet in the area of the head chip arrangement hole. A second step of forming the nozzle row to be disposed;
The liquid chamber is formed in the head chip arrangement hole so that each energy generating element of the head chip and each nozzle formed in the nozzle sheet in the area of the head chip arrangement hole face each other. A third step of disposing the head chip provided with a member;
Forming the head module by a step including a fourth step of disposing the buffer tank on a surface opposite to the bonding surface of the module frame and the nozzle sheet;
The head module formed in the fourth step is disposed in the head module disposition hole of the head frame, and the flange portion of the module frame and the head frame project partially or entirely from the outer surface of the buffer tank. fifth step and the manufacturing method of including a liquid discharge head bonding and.