JP6686815B2 - INKJET HEAD, INKJET RECORDING DEVICE, AND INKJET HEAD MANUFACTURING METHOD - Google Patents

Description

  The present invention relates to an inkjet head, an inkjet recording device, and a method for manufacturing an inkjet head.

2. Description of the Related Art Conventionally, there is known an inkjet recording apparatus that ejects ink droplets from a plurality of nozzles provided on an inkjet head to form an image on a recording medium.
In an inkjet head mounted on an inkjet recording apparatus, if bubbles or foreign matters are present near the nozzles, the ejection performance may be deteriorated. Therefore, maintenance work is required to remove these bubbles or foreign matters. Here, there is a problem that productivity will be significantly reduced if the maintenance work takes time.

Therefore, there is known an inkjet recording apparatus capable of removing bubbles and the like in the vicinity of the nozzle together with the ink by providing a head chip of the inkjet head with a flow path capable of circulating the ink in the vicinity of the nozzle.
For example, Patent Document 1 discloses an inkjet head including a pressure chamber that stores ink ejected from a nozzle and a communication channel (high impedance channel) that is connected to the vicinity of the nozzle. In the inkjet head, by causing ink to flow from the communication channel toward the nozzle, bubbles and the like near the nozzle can be discharged to the manifold side via the pressure chamber.

Further, in Patent Document 2, a pressure chamber formed by a partition wall made of a piezoelectric material that stores ink ejected from a nozzle, an individual communication channel connected to the vicinity of the nozzle, and ink from the individual communication channel merge. There is disclosed an inkjet head including a common flow path for discharging ink and a flow path for discharging ink to the outside of the head. In the inkjet head, the individual communication flow paths and the common flow path are provided on the substrate provided with the nozzles, and bubbles and the like near the nozzles can be discharged together with the ink to the outside of the inkjet head. .
In addition, in the inkjet heads described in Patent Documents 1 and 2, it is possible to remove bubbles and the like in the vicinity of the nozzle while ejecting ink from the nozzle, so it is possible to suppress a decrease in productivity due to separate maintenance work.

Japanese Patent No. 5047958 Japanese Patent No. 5381915

  However, the inkjet head described in Patent Document 1 requires a communication channel (high impedance channel) having a relatively large volume, a pressure chamber, and the like inside the head chip, and when the inkjet head is configured to have a large number of nozzles, the size increases. There is a problem of doing. Here, particularly in an inkjet recording apparatus (see FIG. 1) in which an inkjet head is fixed to a drum that rotates a recording medium for continuous printing, if the inkjet is large, the distance between the recording medium and each nozzle of the inkjet head is constant. It becomes difficult to maintain the high quality, and it becomes difficult to perform high-definition printing. Therefore, it is required to reduce the size of the inkjet head. In addition, it is desirable to reduce the size of the inkjet head from the viewpoint of increasing the manufacturing cost due to an increase in the materials used for manufacturing and saving the space of the apparatus.

  Further, in the inkjet head described in Patent Document 2, the pressure chambers (channels) are formed by partition walls made of a piezoelectric material, and the partition walls can be miniaturized by arranging the partition walls at equal intervals. However, since the individual communication flow paths and the common flow path are formed only in a narrow area of the substrate on which the nozzles are provided, it is difficult to reduce the flow path resistance of these flow paths, and it is sufficient to discharge bubbles and the like. It is difficult to generate a stable ink circulation flow.

  The present invention has been made in view of the above problems, and a problem to be solved is an inkjet head, an inkjet recording device, and an inkjet device having a flow path that can be miniaturized and can effectively discharge bubbles and the like. A method of manufacturing a head is provided.

In order to solve the above problems, the invention described in claim 1 is
A nozzle layer having a plurality of nozzles for ejecting ink,
A pressure chamber layer that is laminated on the nozzle layer, communicates with each of the plurality of nozzles, and has a plurality of pressure chambers that store ink to be ejected from the plurality of nozzles;
An inkjet head for ejecting ink by applying pressure to the pressure chamber,
It is formed in at least one of a portion of the nozzle layer facing the pressure chamber layer and a portion of the pressure chamber layer facing the nozzle layer, communicates with each of the plurality of pressure chambers, and discharges ink from the pressure chambers. Multiple individual communication channels possible,
A plurality of individual communication channels are connected, and a common channel where the ink discharged from the plurality of individual communication channels merges,
A discharge flow path communicating with the common flow path, capable of discharging ink from the common flow path to the outside of the pressure chamber layer,
The common flow path has a narrowed portion in which the cross-sectional area of the flow path becomes narrower in the direction in which ink is discharged, and the narrowed portion is connected to the discharge flow path ,
The common channel is characterized by straight passages der Rukoto.

The invention according to claim 2 is
A nozzle layer having a plurality of nozzles for ejecting ink,
A pressure chamber layer that is laminated on the nozzle layer, communicates with each of the plurality of nozzles, and has a plurality of pressure chambers that store ink to be ejected from the plurality of nozzles;
An inkjet head for ejecting ink by applying pressure to the pressure chamber,
It is formed in at least one of a portion of the nozzle layer facing the pressure chamber layer and a portion of the pressure chamber layer facing the nozzle layer, communicates with each of the plurality of pressure chambers, and discharges ink from the pressure chambers. Multiple individual communication channels possible,
A plurality of individual communication channels are connected, and a common channel where the ink discharged from the plurality of individual communication channels merges,
A discharge flow path communicating with the common flow path, capable of discharging ink from the common flow path to the outside of the pressure chamber layer,
The common flow path has a narrowed portion in which the cross-sectional area of the flow path becomes narrower in the direction in which ink is discharged, and the narrowed portion is connected to the discharge flow path,
The common channel is characterized in that at least one end of the channel is sealed by the throttle portion.
The invention according to claim 3 is
A nozzle layer having a plurality of nozzles for ejecting ink,
A pressure chamber layer that is laminated on the nozzle layer, communicates with each of the plurality of nozzles, and has a plurality of pressure chambers that store ink to be ejected from the plurality of nozzles;
An inkjet head for ejecting ink by applying pressure to the pressure chamber,
It is formed in at least one of a portion of the nozzle layer facing the pressure chamber layer and a portion of the pressure chamber layer facing the nozzle layer, communicates with each of the plurality of pressure chambers, and discharges ink from the pressure chambers. Multiple individual communication channels possible,
A plurality of individual communication channels are connected, and a common channel where the ink discharged from the plurality of individual communication channels merges,
A discharge flow path communicating with the common flow path, capable of discharging ink from the common flow path to the outside of the pressure chamber layer,
The common flow path has a narrowed portion in which the cross-sectional area of the flow path becomes narrower in the direction in which ink is discharged, and the narrowed portion is connected to the discharge flow path,
At least one end of the common channel is provided with a sealing member for sealing the common channel.
According to a fourth aspect of the present invention, in the inkjet head according to any one of the first to third aspects,
The common flow path is provided at least in a portion of the pressure chamber layer facing the nozzle layer.

According to a fifth aspect of the invention, in the inkjet head according to the fourth aspect ,
The width of the common channel in the ink ejection direction is larger than the thickness of the nozzle layer.

According to a sixth aspect of the invention, in the inkjet head according to any one of the first to fifth aspects,
The throttle unit is characterized in that prior Symbol ink in the common flow path is provided in the discharge direction of the ink than the individual communication passage provided in the most discharge direction side in the direction to be discharged.

The invention described in claim 7 is the inkjet head according to any one of claims 1 to 6 ,
It is characterized in that the narrowed portion is formed so that the cross-sectional area becomes gradually smaller in the direction in which the ink is discharged.

The invention described in claim 8 is the inkjet head according to any one of claims 1 to 7 ,
The discharge channel is a channel capable of discharging ink from the common channel toward the side opposite to the nozzle layer,
The cross-sectional area of the discharge channel is larger than the maximum cross-sectional area of the common channel.

According to a ninth aspect of the invention, in the inkjet head according to any one of the first to eighth aspects,
A manifold for storing ink to be supplied to the plurality of pressure chambers,
The manifold is provided in an upper portion of the pressure chamber opposite to the nozzle layer side .

The invention described in claim 10 is
An inkjet head according to any one of claims 1 to 9 ,
Ink circulation means for generating a circulation flow from the pressure chamber to the individual communication flow path,
An ink jet recording apparatus comprising:

The invention according to claim 11 is
A method for manufacturing an inkjet head according to any one of claims 1 to 9 ,
The common channel is formed by scanning the pressure chamber layer with a dicing blade.
The invention according to claim 12 is
A nozzle layer having a plurality of nozzles for ejecting ink,
A pressure chamber layer that is laminated on the nozzle layer, communicates with each of the plurality of nozzles, and has a plurality of pressure chambers that store ink to be ejected from the plurality of nozzles;
An inkjet head for ejecting ink by applying pressure to the pressure chamber,
It is formed in at least one of a portion of the nozzle layer facing the pressure chamber layer and a portion of the pressure chamber layer facing the nozzle layer, communicates with each of the plurality of pressure chambers, and discharges ink from the pressure chambers. Multiple individual communication channels possible,
A plurality of individual communication channels are connected, and a common channel where the ink discharged from the plurality of individual communication channels merges,
A discharge flow path communicating with the common flow path, capable of discharging ink from the common flow path to the outside of the pressure chamber layer,
The method for manufacturing an inkjet head, wherein the common flow channel has a narrowed portion in which a cross-sectional area of the flow channel becomes narrower in a direction in which ink is discharged, and the narrowed portion is connected to the discharge flow channel. ,
The common channel is formed by scanning the pressure chamber layer with a dicing blade.

The invention according to claim 13 is
It is a manufacturing method of the inkjet head according to claim 11 or 12,
When forming the common channel, the dicing blade is moved so as to be shallower in the thickness direction while scanning, thereby forming the narrowed portion in the common channel.

  According to the present invention, it is possible to provide an inkjet head, an inkjet recording apparatus, and a method for manufacturing an inkjet head that have a flow path that can be miniaturized and that can effectively discharge bubbles and the like.

Schematic diagram showing an inkjet recording device Bottom view showing the head unit A perspective view (a) and a sectional view (b) showing an inkjet head. Exploded perspective view showing the inkjet head A perspective view from the top side showing a head chip, a wiring board, a flexible board, and a drive circuit board (a) and a perspective view from the bottom side (b). Exploded perspective view schematically showing the head chip and the wiring board Perspective view from the lower surface side for explaining the flow of ink in the head chip Sectional drawing cut along the line (VIII)-(VIII) in FIG. Sectional drawing which showed the modification of FIG. Sectional view taken along the line (X)-(X) in FIG. Sectional view taken along the line (XI)-(XI) in FIG. Perspective view showing a common channel partially extracted Sectional drawing which showed the modification of FIG. Perspective view showing nozzle layer of head chip Conceptual diagram showing the positional relationship when the pressure chambers in the head chip, the individual communication channels, the common channels, and the discharge channels are viewed in a plan view. FIG. 14 is a dotted line portion (XVI) of FIG. 14, which is an enlarged plan view of the vicinity of the upstream end of the individual communication channel on the upper surface of the nozzle layer. The top view which showed the modification of FIG. The perspective view from the upper surface side which shows a manifold (a) and the perspective view from the lower surface side (b). A perspective view from the top side showing the housing (a) and a perspective view from the bottom side (b) Conceptual diagram showing an ink circulation mechanism in an inkjet recording apparatus

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. However, the scope of the invention is not limited to the illustrated example. In this specification, the arrangement direction of the nozzles 11a of the inkjet head 100 is the left-right direction (see FIG. 2, FIG. 6, FIG. 7, etc.), and the ink ejection direction is the up-down direction. The orthogonal direction will be described as the front-back direction. Further, the arrows in the flow paths in the drawings indicate the directions in which the ink flows.

[Inkjet recording device]
As shown in FIG. 1, the inkjet recording apparatus 200 includes a paper feed unit 210, an image recording unit 220, a paper discharge unit 230, an ink circulation mechanism 8 (see FIG. 20), and the like. The inkjet recording apparatus 200 conveys the recording medium M stored in the paper feeding unit 210 to the image recording unit 220, forms an image on the recording medium M by the image recording unit 220, and ejects the recording medium M on which the image is formed. The paper is conveyed to the paper unit 230.
As the recording medium M, in addition to paper such as plain paper and coated paper, various media such as cloth or sheet-shaped resin capable of fixing the ink landed on the surface can be used.

  The paper feeding unit 210 includes a paper feeding tray 211 that stores the recording medium M, and a medium supplying unit 212 that conveys and supplies the recording medium M from the paper feeding tray 211 to the image recording unit 220. The medium supply unit 212 includes a ring-shaped belt whose inner side is supported by two rollers, and the rollers are rotated while the recording medium M is placed on the belt to move the recording medium M from the paper feed tray 211. The image is conveyed to the image recording unit 220.

  The image recording unit 220 includes a transport drum 221, a delivery unit 222, a heating unit 223, a head unit 224, a fixing unit 225, a delivery unit 226, and the like.

  The transport drum 221 has a cylindrical surface, and the outer peripheral surface thereof is a transport surface on which the recording medium M is placed. The transport drum 221 transports the recording medium M along the transport surface by rotating in the direction of the arrow in FIG. 1 while holding the recording medium M on the transport surface. Further, the transport drum 221 includes a claw portion and an air intake portion (not shown). The edge portion of the recording medium M is pressed by the claw portion, and the air suction portion attracts the recording medium M to the transport surface. Holds the recording medium M.

  The delivery unit 222 is provided at a position between the medium supply unit 212 of the paper feed unit 210 and the transport drum 221. One end of the recording medium M transported from the medium supply unit 212 is held by the swing arm unit 222a and picked up. Then, it is delivered to the transport drum 221 via the delivery drum 222b.

  The heating unit 223 is provided between the arrangement position of the transfer drum 222b and the arrangement position of the head unit 224, and the recording medium M conveyed by the conveyance drum 221 has a temperature within a predetermined temperature range. Heat M. The heating unit 223 has, for example, an infrared heater, and energizes the infrared heater based on a control signal supplied from a control unit (not shown) to heat the heater.

  The head unit 224 forms an image by ejecting ink onto the recording medium M at an appropriate timing according to the rotation of the transport drum 221 holding the recording medium M based on the image data. The head unit 224 is arranged such that the ink ejection surface thereof faces the transport drum 221 with a predetermined distance. In the inkjet recording apparatus 200 according to the present embodiment, for example, four head units 224 corresponding to four color inks of yellow (Y), magenta (M), cyan (C), and black (K) are used as the recording medium M. Are arranged in the order of colors Y, M, C, and K from the upstream side in the transport direction so as to be arranged at predetermined intervals.

  As shown in the bottom view of FIG. 2, in the head unit 224, a pair of inkjet heads 100 that are adjacent to each other in the front-rear direction are arranged in a zigzag pattern at different positions in the front-rear direction. With such an arrangement of the inkjet head 100, the width of the nozzle 11a of the inkjet head 100 arranged in the left-right direction is equal to or larger than the width of the area where the image is formed on the recording medium M. It has become. Further, the head unit 224 is used with a fixed position with respect to the rotation axis of the transport drum 221 during image recording. That is, the inkjet recording apparatus 200 is an inkjet recording apparatus that performs image recording of a one-pass drawing method using a line head.

As the ink ejected from the nozzle 11a of the inkjet head 100, for example, one that has a property of undergoing a phase change into a gel or a sol according to temperature and being cured by being irradiated with an energy ray such as ultraviolet rays is used.
In addition, in the present embodiment, for example, an ink that is gel at room temperature and becomes sol when heated is used. The head unit 224 includes an ink heating unit (not shown) that heats the ink stored in the head unit 224, and the ink heating unit can heat the ink to a sol-like temperature. The inkjet head 100 ejects the sol-like ink that is heated. When this sol-like ink is ejected onto the recording medium M, the ink droplets land on the recording medium M and are then naturally cooled, whereby the ink rapidly becomes a gel state and solidifies on the recording medium M.

  The fixing unit 225 has a light emitting unit arranged across the width of the conveying drum 221 in the X direction, and irradiates the recording medium M placed on the conveying drum 221 with energy rays such as ultraviolet rays from the light emitting unit. Then, the ink ejected onto the recording medium M is cured and fixed. The light emitting unit of the fixing unit 225 is arranged on the downstream side of the arrangement position of the head unit 224 and on the upstream side of the arrangement position of the delivery drum 226a of the delivery unit 226 in the conveyance direction so as to face the conveyance surface.

  The delivery unit 226 has a belt loop 226b having a ring-shaped belt whose inner side is supported by two rollers, and a cylindrical delivery drum 226a that delivers the recording medium M from the transport drum 221 to the belt loop 226b. The recording medium M transferred from the transfer drum 221 to the belt loop 226b by the transfer drum 226a is transferred by the belt loop 226b and sent to the paper output unit 230.

  The paper discharge unit 230 has a plate-shaped paper discharge tray 231 on which the recording medium P sent from the image recording unit 220 by the delivery unit 226 is placed.

[Inkjet head]
FIG. 3A is a perspective view showing an inkjet head 100 of an embodiment to which the present invention is applied, and FIG. 3B is a sectional view of the inkjet head 100. Further, FIG. 4 is an exploded perspective view showing the inkjet head 100. Note that the manifold 5 is not shown in FIG. 3A, and the cover member 9 is not shown in FIGS. 3B and 4.
Although the present embodiment describes an example in which the nozzle row of the head chip 1 is two rows, the number and arrangement of the nozzles 11a can be changed as appropriate, for example, one row or three or more rows. May be.

  As shown in FIGS. 3 and 4, the inkjet head 100 of the present embodiment is connected via a head chip 1, a wiring board 2 on which the head chip 1 is arranged, a wiring board 2 and a flexible board 3. Drive circuit board 4, a manifold 5 for storing ink to be supplied to the pressure chamber 13A in the head chip 1, a housing 6 in which the manifold 5 is housed, and a mounting so as to close a bottom opening of the housing 6. The cap receiving plate 7 and the cover member 9 attached to the housing 6 are provided. The ejection method of the inkjet head 100 of the present embodiment is not particularly limited, but the share mode inkjet head 100 will be described as an example.

  The head chip 1 is a substantially quadrangular prismatic member that is long in the left-right direction, and is composed of a nozzle layer 11 and a pressure chamber layer 12 (see FIGS. 6 and 7 and the like). 7 to 14, only a partial region of the head chip 1 is enlarged and schematically shown, and the region on the left end side of the head chip 1 is not shown.

The pressure chamber layer 12 is provided with a pressure chamber 13A, a discharge channel 13B, a common channel 19, and the like.
The pressure chamber 13A is formed by being separated by a partition made of a piezoelectric material, and stores ink to be ejected from the nozzle 11a. A drive electrode 14 for driving the partition between the adjacent pressure chambers 13A is provided on the inner surface of each pressure chamber 13A. When a voltage is applied to the drive electrode 14, the partition between the adjacent pressure chambers 13A is provided. The pressure is applied to the ink in the pressure chamber 13A by repeating the share mode displacement of the portion. In the present embodiment, the drive electrode 14 is a metal film.

  Each pressure chamber 13A has a substantially rectangular cross section and is formed along the vertical direction, and has an inlet on the upper surface of the pressure chamber layer 12 and an outlet on the lower surface. Further, each pressure chamber 13A is a straight type whose size and shape do not change substantially in the length direction (vertical direction) from the inlet to the outlet, and the plurality of pressure chambers 13A, ... Are arranged in parallel with each other. There is. The plurality of pressure chambers 13A are arranged in the left-right direction and formed in two rows in the front-rear direction. The drive electrodes 14 are not illustrated except for FIG. 6.

Like the pressure chamber 13A, the discharge flow path 13B is formed so as to be separated by a partition wall, and a flow for discharging the ink to the outside of the inkjet head 100 toward the upper side (the side opposite to the nozzle layer 11 side). It is a road. The discharge flow path 13B is formed along the up-down direction, and has an outlet on the upper surface of the pressure chamber layer 12 and an inlet on the lower surface. Further, the discharge flow path 13B is a straight type whose size and shape do not substantially change in the length direction (vertical direction) from the inlet to the outlet, and is arranged side by side in parallel with the pressure chambers 13A ,. Two head chips 1 are formed near the right end.
In addition, as shown in FIGS. 6, 10 and 11, the discharge flow path 13B has a larger volume than the pressure chamber 13A from the viewpoint of decreasing the flow path resistance of the head chip 1 as a whole and increasing the ink discharge efficiency. Is preferably provided. From the same viewpoint, it is preferable that the cross-sectional area of the discharge channel 13B be larger than the maximum cross-sectional area of the common channel 19.

The common flow passage 19 is a flow passage to which the individual communication flow passages 18 communicating with the pressure chamber 13A are connected, and the inks flowing from the individual communication flow passages 18 merge. The common flow path 19 is preferably provided at least in a portion of the pressure chamber layer 12 facing the nozzle layer 11. In the example shown in FIGS. 8, 11, and 14 and the like, an example is shown in which the portion of the pressure chamber layer 12 that faces the nozzle layer 11 and the portion of the nozzle layer 11 that faces the pressure chamber layer 12 are formed. However, it is not necessarily formed over the nozzle layer 11, and may be formed only in the portion of the pressure chamber layer 12 facing the nozzle layer 11.
The common flow path 19 is provided for each nozzle row so as to be parallel to the left-right direction, and communicates with the discharge flow path 13B near the right end of the common flow path (FIGS. 6, 7, and FIG. 11). In this embodiment, since the common channel 19 is provided in the pressure chamber layer 12, the width of the common channel 19 in the ink ejection direction (vertical direction) is made larger than the thickness of the nozzle layer 11, The volume of the flow channel can be made larger than that when the common flow channel 19 is provided only in the nozzle layer 11. Further, by providing the common channel 19 having a large volume, the circulation amount of the ink in the head chip 1 can be increased, so that bubbles and the like can be effectively discharged. Further, heat dissipation of the head chip 1 can be effectively performed.
Further, the common flow path 19 is formed to be a linear flow path. As a result, it is possible to effectively discharge precipitates, bubbles, etc. in the ink together with the ink.

Further, as shown in FIG. 12 which is a perspective view in which the common flow path 19 formed in the head chip 1 is partially extracted, the common flow path 19 has a flow path in the direction D1 in which ink is discharged. Is provided with a narrowed portion 19a having a narrow cross-sectional area 19b, and the narrowed portion 19a is connected to the discharge flow path 13B.
Further, from the viewpoint of manufacturing efficiency, it is preferable that the narrowed direction of the flow path in the narrowed portion 19a is narrowed in the thickness direction (vertical direction) (see FIG. 11), but it is not limited to this. The width may be narrowed in the width direction (front-back direction) of the common channel 19 (see FIG. 15), or both of them may be narrowed. When the narrowed portion 19a is formed in the common flow passage 19, the flow velocity in the common flow passage 19 is increased, so that it is possible to reduce the accumulation of precipitates and bubbles in the ink in the common flow passage 19.

  Further, as shown in FIG. 15, the throttle portion 19a is located outside the individual communication passages 18a provided at the end of the common flow passage 19 in the ink discharge direction (on the ink discharge direction side). It is preferably provided. As a result, the flow velocity of the ink is less likely to change near the area where the individual communication flow passage 18 is provided, so that it is possible to reduce the influence on the ejection of the ink by increasing the flow velocity of the ink in the common flow passage 19. Note that FIG. 15 is a conceptual diagram showing a positional relationship when the pressure chamber 13A, the individual communication flow path 18, the common flow path 19 and the discharge flow path 13B in the head chip 1 are viewed in a plan view. The arrow indicates the direction of ink discharge. Further, for the sake of convenience of description, the individual communication flow paths 18 provided at the ends in the direction in which the ink is discharged are shown as 18a.

  Further, as shown in FIG. 12 and the like, it is preferable that the narrowed portion 19a is formed so that the cross-sectional area becomes gradually smaller in the ink discharge direction. As a result, bubbles are less likely to be caught on the wall surface of the common flow path 19, so that precipitates and bubbles in the ink can be efficiently discharged together with the ink.

  Further, the common channel 19 can be formed by scanning the pressure chamber layer 12 with a dicing blade. Further, when forming the common channel 19, the narrowed portion 19a can be formed by scanning the dicing blade so as to be shallow in the thickness direction (Z direction). By processing with a dicing blade, the common channel 19 can be easily formed with high accuracy.

  The nozzle layer 11 is a rectangular plate-shaped member, and is arranged on the lower surface of the pressure chamber layer 12 so as to close the lower ends of the pressure chamber 13A and the discharge flow passage 13B. Further, the nozzle layer 11 is provided with the nozzle 11a, the individual communication flow paths 18, and the like.

  The nozzle 11a is provided at a position facing each pressure chamber 13A in the nozzle layer 11 so as to penetrate in the thickness direction (vertical direction), and ejects the ink stored in the communicating pressure chamber 13A. . In addition, in this embodiment, the nozzles 11a are arranged in the left-right direction and form two rows in the front-rear direction.

The individual communication flow path 18 is formed in a portion of the nozzle layer 11 facing the pressure chamber layer 12 so as to extend in the front-rear direction from the nozzle 11a side toward the common flow path 19, and is shared with the pressure chamber 13A. It communicates with the flow path 19 (see FIG. 8, FIG. 14, etc.).
In the present embodiment shown in FIG. 8, the individual communication flow passage 18 is formed only in the portion of the nozzle layer 11 that faces the pressure chamber layer 12, but the pressure chamber 13A and the common flow passage 19 are communicated with each other. In this case, it may be formed on at least one of the portion of the nozzle layer 11 facing the pressure chamber layer 12 and the portion of the pressure chamber layer 12 facing the nozzle layer 11. For example, it may be provided only in a portion of the pressure chamber layer 12 facing the nozzle layer 11, or may be formed so as to straddle the nozzle layer 11 and the pressure chamber layer 12.

In addition, in the present embodiment, the individual communication flow path 18 is provided only toward the common flow path 19 closer to the nozzle 11a than the common flow path 19 provided for each nozzle row. (FIGS. 8 and 14), but is not limited thereto. For example, as shown in a modified example in FIG. 9, common channels 19 parallel to the front-rear direction are provided on both sides of the pressure chamber 13A in the front-rear direction, and the common channels 19 are provided to both of the common channels 19 and 19, respectively. Thus, the individual communication channels 18, 18 may be provided. With such a configuration, the amount of ink circulation can be further increased, and thus bubbles and the like can be more effectively discharged.
Further, when the individual communication flow passages 18 are provided in the nozzle layer 11, it is preferable that the common flow passage 19 is formed so as to extend over the nozzle layer 11. This makes it easier for the ink flowing from the individual communication flow paths 18 to flow into the common flow path 19 of the pressure chamber layer 12.

FIG. 11 shows a cross section (cross section taken along line XI-XI in FIG. 7) obtained by cutting the head chip 1 in the vertical direction so as to pass through the common flow path 19. The right end portion of the common flow channel 19 in the longitudinal direction (left-right direction) is sealed at the end of the flow channel by the narrowed portion 19a. Specifically, the width of the common channel 19 in the vertical direction (ink ejection direction) becomes narrower toward the ink discharge direction, and the upper and lower surfaces of the common channel 19 are connected and sealed (FIG. 12). ). With such a configuration, the end portion of the common channel 19 can be sealed only by joining the nozzle layer 11 and the pressure chamber layer 12.
The configuration for sealing the common flow channel 19 can be changed to an appropriate configuration as long as it is sealed so that ink does not leak from the common flow channel 19.
For example, the sealing member 12c may be provided at the right end portion in the longitudinal direction (left-right direction) of the common channel 19 and the end portion may be sealed by the sealing member 12c (FIG. 13). With such a configuration, when forming the common flow passage 19 in the pressure chamber layer 12, the common flow passage 19 can be formed so as to penetrate to the side surface portion in the left-right direction (longitudinal direction of the common flow passage 19). The manufacturing efficiency can be improved.
Although the region on the left end side is not shown in FIGS. 11 and 13, it is preferable that the side face portion of the common channel 19 is sealed by the same method as that on the right end side.

FIG. 16 shows an enlarged plan view (dotted line part (XVI) of FIG. 13) in the vicinity of the upstream end of the individual communication flow path 18 on the upper surface of the nozzle layer 11. As shown in FIGS. 8 and 16, the nozzle layer 11
A rectangular recess 11b is provided above the nozzle 11a, and the nozzle 11a is bored in the recess 11b. Further, as shown in FIG. 16, it is preferable that the upstream end of the individual communication flow path 18 is formed in a tapered shape such that the width becomes wider toward the recess 11b side (upstream side). With such a shape, bubbles are less likely to be caught, and thus bubbles existing near the nozzle 11a can be easily discharged.
Further, FIG. 17 shows a plan view in which the vicinity of the upstream end portion of the individual communication channel 18 is enlarged in the case where the head chip 1 has the configuration shown in the modification shown in FIG. In this modified example, the individual communication flow paths 18 and 18 are provided from the recess 11b of the nozzle layer 11 toward the common flow paths 19 and 19 provided on the front side and the rear side, respectively.

  In the nozzle layer 11 as described above, the nozzles 11a, the recesses 11b, and the individual communication channels 18 are evenly formed by, for example, a method of laser processing a plate of a polyimide material or a method of etching a plate of a silicon material. It can be manufactured by forming it. The material of the nozzle layer 11 may be resin or metal as long as it can be etched.

  As shown in FIGS. 5A and 5B, the wiring board 2 is disposed on the upper surface of the head chip 1, and the drive circuit board 4 is provided at both edges of the wiring board 2 in the left-right direction. , 4 are connected to the two flexible substrates 3, 3.

  The wiring board 2 is formed in a substantially rectangular plate shape that is long in the left-right direction, and has an opening 22 at a substantially central portion thereof. The widths of the wiring board 2 in the left-right direction and the front-back direction are formed to be larger than those of the head chip 1.

  The opening 22 is formed in a substantially rectangular shape that is long in the left-right direction, and when the head chip 1 is attached to the wiring board 2, the openings of the pressure chambers 13A in the head chip 1 and the discharge flow path. The outlet of 13B is exposed to the upper side.

  In addition, a predetermined number of electrode portions 21 connected to the electrodes (not shown) drawn from the drive electrodes 14 of the head chip 1 to the upper surface of the head chip 1 are arranged at the front and rear edges of the opening 22. (Fig. 6).

  Further, as shown in FIGS. 4 and 5, a flexible substrate 3 is provided at each of the front and rear edges of the wiring substrate 2.

  As shown in FIG. 6, the flexible board 3 has a plurality of wirings 31, ... For electrically connecting the drive circuit board 4 and the electrode portion 21 of the wiring board 2. As a result, the signal from the drive circuit board 4 is applied to the drive electrode 14 in each pressure chamber 13A of the head chip 1 via the wiring 31 and the electrode portion 21.

  Further, as shown in FIG. 4, the lower end of the manifold 5 is attached and fixed to the outer edge of the wiring board 2 by adhesion. That is, the manifold 5 is disposed on the inlet side (upper side) of the pressure chamber 13A of the head chip 1 and is connected to the head chip 1 via the wiring board 2.

  The manifold 5 is a member formed of resin, is provided above the pressure chamber 13A of the head chip 1, and stores the ink introduced into the pressure chamber 13A therein. Specifically, as shown in FIG. 3B, FIG. 18A, FIG. 18B, etc., the manifold 5 is elongated in the left-right direction and constitutes the ink storage portion 51. It is provided with a hollow main body portion 52 and first to fourth ink ports 53 to 56 forming ink flow paths.

  The main body portion 52 is formed in a concave shape with a lower opening, and a wiring board attachment portion 521 to which the wiring board 2 is attached and fixed is provided at an edge portion of the lower end opening thereof. Then, the wiring board 2 having the head chip 1 is attached to the wiring board attachment portion 521 so as to close the lower end opening, whereby the ink storage portion 51 is configured.

  The first ink port 53 communicates with the upper right end of the ink storage portion 51. Further, the second ink port 54 is communicated with the upper left end of the ink storage portion 51, and the third ink port 55 is communicated with the lower left side of the portion with which the second ink port 54 is communicated. There is. Further, a discharge liquid chamber 57 communicating with the discharge channel 13B of the head chip 1 is defined at the lower right end of the ink storage portion 51, and the discharge liquid chamber 57 has a fourth ink port 56. It is in communication.

Further, as shown in FIG. 3B, a filter F for removing dust in the ink is arranged inside the main body 52 and at a position slightly lower in the vertical center of the ink reservoir 51. It is set up.
Further, as shown in FIGS. 3B and 8B, etc., the ink storage portion 51 is formed at substantially the same height in the vertical direction from the lower end portion of the main body portion 52 toward the upper side. The inner side surface portion 511 is provided. Here, the ink storage portion 51 extends inward from the upper end of the inner side surface portion 511 by a predetermined length substantially in parallel with the front-rear direction and the left-right direction, and the outer edge portion of the substantially rectangular filter F is in contact with the ink storage portion 51. A filter edge mounting portion 512 is provided in contact therewith.
In addition, at the left end of the filter edge attachment portion 512 and between the second ink port 54 and the third ink port 55, the inner side surface portion 511 is formed so as to extend across the front surface and the rear surface, and the left end of the filter F is formed. An end-side filter mounting portion 513 is provided, which is in contact with the inner side of the filter. The end side filter mounting portion 513 is formed at a height substantially equal to the filter edge mounting portion 512.
Then, the filter F is attached and fixed to the end side filter attachment portion 513 and the filter edge attachment portion 512 by adhesion.

  As described above, by disposing the filter F in the ink storage portion 51, the ink storage portion 51 is connected to the first ink port 53 and the second ink port 54, and the first liquid chamber 51a and the head chip. The second liquid chamber 51b is communicated with each pressure chamber 13A in FIG. Of these, the second liquid chamber 51b communicates with the third ink port 55 via the filter F.

  The first ink port 53 is for introducing ink into the ink storage portion 51, for example. The first ink port 53 is formed in a cylindrical shape extending in the vertical direction, and has an outer diameter that is substantially the same in the vertical direction. Further, the first ink port 53 is adapted to be inserted into a first insertion hole 66 (described later) of the housing 6 when the manifold 5 is attached to the housing 6, and the first ink port 53 of the first ink port 53 The outer diameter is substantially equal to or slightly smaller than the inner diameter of the first insertion hole 66.

  Further, the first joint 81a is adapted to be externally attached to the tip of the first ink port 53. That is, when the manifold 5 is attached to the housing 6, the first joint 81a is vertically slidable at the tip of the first ink port 53 that is inserted into the first insertion hole 66 and projects from the upper surface of the housing 6. Is extrapolated to. The first joint 81a is a bamboo shoot joint (joint member) to which an unillustrated ink supply pipe is connected to the upper end portion. Specifically, the first joint 81a is formed in a tubular shape extending in the up-down direction, the ink pipe connecting portion 811 is formed at the upper end portion thereof, and the first ink port is formed below the ink pipe connecting portion 811. A tip insertion portion 812 into which the tip portion of 53 is inserted is provided.

The second ink port 54 is for removing bubbles in the first liquid chamber 51a, for example. The second ink port 54 is formed in a shape substantially the same as the first ink port 53.
That is, the second ink port 54 is formed in a cylindrical shape extending in the vertical direction, and has an outer diameter that is substantially equal in the vertical direction. Further, the second ink port 54 is adapted to be inserted into a second insertion hole 64 (described later) of the housing 6 when the manifold 5 is attached to the housing 6, and the second ink port 54 is The outer diameter is substantially equal to or slightly smaller than the inner diameter of the second insertion hole 64.

  Further, the second joint 81b is adapted to be externally inserted at the tip of the second ink port 54. That is, when the manifold 5 is attached to the housing 6, the second joint 81b is vertically slidable at the tip of the second ink port 54 which is inserted into the second insertion hole 64 and protrudes from the upper surface of the housing 6. Is extrapolated to. In the second joint 81b, a tip insertion portion 812 into which the tip of the second ink port 54 is slidably inserted in the vertical direction is formed in the lower portion. The configuration of the second joint 81b is substantially the same as that of the first joint 81a externally inserted in the second ink port 54, and detailed description thereof will be omitted.

  The third ink port 55 is for removing bubbles in the second liquid chamber 51b, for example. The third ink port 55 is formed in a cylindrical shape extending in the vertical direction and has an outer diameter that is substantially equal in the vertical direction. The third ink port 55 is adapted to be inserted into a third insertion hole 65 (described later) of the housing 6 when the manifold 5 is attached to the housing 6. The outer diameter is substantially equal to or slightly smaller than the inner diameter of the third insertion hole 65.

  Further, the third joint 82 is adapted to be externally fitted to the tip of the third ink port 55 (see FIG. 3A, etc.). That is, when the manifold 5 is attached to the housing 6, the third joint 82 is vertically slidable at the tip of the third ink port 55 that is inserted into the third insertion hole 65 and projects from the upper surface of the housing 6. Is extrapolated to. The third joint 82 has the dimensions of the first joint 81a and the second joint 81b reduced so that it can be externally inserted into the tip portion of the third ink port 55, and the main configuration thereof is the first joint. 81a and the second joint 81b are substantially the same, and thus detailed description thereof will be omitted.

  The fourth ink port 56 is for discharging bubbles in the pressure chamber 13A of the head chip 1 to the outside of the inkjet head 100 via the individual communication flow path 18, the common flow path 19 and the discharge flow path 13B. The fourth ink port 56 is formed in a cylindrical shape extending in the vertical direction, and has an outer diameter that is substantially equal in the vertical direction. Further, the fourth ink port 56 is adapted to be inserted into a discharge insertion hole 67 (described later) of the housing 6 when the manifold 5 is attached to the housing 6, and the fourth ink port 56 of the fourth ink port 56. The outer diameter is substantially equal to or slightly smaller than the inner diameter of the discharge insertion hole 67.

  Next, the housing 6 will be described with reference to FIGS. 19 (a) and 19 (b).

The housing 6 is a member formed by die-casting using aluminum as a material, and is formed to be long in the left-right direction. The housing 6 is formed so as to be able to accommodate the manifold 5 having the head chip 1, the wiring board 2, and the flexible board 3 mounted therein, and the bottom surface of the housing 6 is open.
Specifically, a substantially rectangular lower opening 61 that is long in the left-right direction is formed at the lower end of the housing 6, and the head chip 1 and the wiring are formed through the lower opening 61. The manifold 5 to which the substrate 2 and the flexible substrate 3 are attached can be arranged inside the housing 6 so as to be inserted from the lower side.

A cap receiving plate attachment portion 62 to which the cap receiving plate 7 (see FIG. 4 and the like) is attached and fixed is provided at the edge of the lower opening 61.
As shown in FIG. 4, the cap receiving plate 7 is formed into a substantially rectangular plate shape having an outer shape elongated in the left-right direction in accordance with the shape of the cap receiving plate attachment portion 62, and the nozzle layer 11 is formed in the substantially central portion thereof. An elongated nozzle opening 71 is formed in the left-right direction exposing the nozzle.
Then, after disposing the manifold 5 to which the head chip 1, the wiring board 2 and the flexible board 3 are attached inside the housing 6, the nozzle layer 11 is exposed through the nozzle opening 71 and the cap receiving is performed. By attaching the plate 7 to the cap receiving plate attachment portion 62, the lower opening 61 of the housing 6 is closed.

Further, as shown in FIG. 4, FIG. 9A, FIG. 9B, and the like, two drive circuit boards 4, 4 connected to the manifold 5 are provided at a substantially central portion in the left-right direction of the housing 6. Two board insertion openings 63 through which the flexible boards 3 and 3 are inserted are formed.
The board insertion openings 63, 63 are closed by attaching a cover member 9 (see FIG. 3A) to the housing 6.

  A second insertion hole 64 through which the tip of the second ink port 54 of the manifold 5 is inserted is formed on the left side of the two board insertion openings 63, 63 of the housing 6, and is slightly smaller than the second insertion hole 64. A third insertion hole 65, through which the tip of the third ink port 55 of the manifold 5 is inserted, is formed on the left side and lower than the second insertion hole 64 (see FIG. 3B). .

  The second insertion hole 64 is provided in the upper left recess 641 recessed from the left first upper surface 6a of the housing 6 by a predetermined depth, and is formed so as to vertically penetrate the bottom surface of the upper left recess 641. There is. The second insertion hole 64 has a diameter substantially equal to or slightly larger than the outer diameter of the second ink port 54. Furthermore, the outer edge portion of the second insertion hole 64 is formed substantially parallel to the left-right direction and the front-back direction.

  The third insertion hole 65 is disposed in the lower left recess 651 which is recessed by a predetermined depth from the left second upper surface 6b lower than the left first upper surface 6a, and vertically penetrates the bottom surface of the lower left recess 651. Is formed in. The third insertion hole 65 has a diameter substantially equal to or slightly larger than the outer diameter of the third ink port 55. Further, the outer edge portion of the third insertion hole 65 is formed substantially parallel to the left-right direction and the front-back direction.

  On the other hand, on the right side of the two board insertion openings 63, 63 of the housing 6, the first insertion through which the tip portion of the first ink port 53 of the manifold 5 is inserted at a height substantially equal to that of the second insertion hole 64. A hole 66 is formed, and the tip end portion of the fourth ink port 56 of the manifold 5 is inserted at a position slightly right of the first insertion hole 66 and lower than the first insertion hole 66. 67 is formed (see FIG. 3B).

  The first insertion hole 66 is disposed in the upper right recess 661 which is recessed from the right first upper surface 6c of the housing 6 by a predetermined depth, and is formed so as to vertically penetrate the bottom surface of the upper right recess 661. There is. Further, the first insertion hole 66 has a diameter substantially equal to or slightly larger than the outer diameter of the first ink port 53. Further, the outer edge portion of the first insertion hole 66 is formed substantially parallel to the left-right direction and the front-back direction.

  The discharge insertion hole 67 is provided in the lower right recess 671 recessed by a predetermined depth from the right second upper surface 6d lower than the right first upper surface 6c, and vertically penetrates the bottom surface of the lower right recess 671. Is formed. Further, the ejection insertion hole 67 has a diameter substantially equal to or slightly larger than the outer diameter of the fourth ink port 56. Further, the outer edge portion of the discharge insertion hole 67 is formed substantially parallel to the left-right direction and the front-back direction.

  Further, mounting holes 68 for mounting the casing 6 on the printer body side are respectively provided at an end portion on the left side of the third insertion hole 65 of the housing 6 and an end portion on the right side of the ejection insertion hole 67. Has been formed.

[Ink circulation mechanism]
The ink jet recording apparatus 200 in this embodiment has an ink circulation mechanism 8 as an ink circulation means. The structure of the ink circulation mechanism 8 is appropriately selected as long as it can generate a circulation flow from the pressure chamber 13A to the individual communication channel 18 and discharge the ink in the pressure chamber 13A from the discharge channel 13B to the outside of the head chip. Although possible, an example thereof will be described below.
The ink circulation mechanism 8 is composed of a main tank 201, a sub tank 202, a circulation flow path 203 and the like (FIG. 20). 20. FIG. 20 is a conceptual diagram for explaining the circulation of ink in the inkjet recording apparatus 200, and the arrow indicates the direction of ink flow.

  The main tank 201 is filled with ink to be supplied to the sub tank 202, and is connected to the sub tank 202 by an ink flow path. Then, for example, ink can be supplied from the main tank 201 to the sub tank 202 by the pressure applied by a pump (not shown) as a pressure generating means.

  The sub tank 202 is filled with ink to be supplied to the inkjet head 100, and is connected to the first ink port 53 of the inkjet head 100 by an ink flow path. Then, for example, ink can be supplied from the sub-tank 202 to the inkjet head 100 by the pressure applied by a pump (not shown) as a pressure generating means. Further, the sub tank 202 has a gas-liquid separation function, and can separate air bubbles from the ink filled inside.

  Here, the ink supplied from the sub tank 202 to the inkjet head 100 flows into each pressure chamber 13A via the first ink port 53 and the ink reservoir 51. That is, in the present embodiment, the first ink port 53 and the ink reservoir 51 function as a flow path that supplies ink to the plurality of pressure chambers 13A from the upstream side of the pressure chambers 13A. . Further, as described above, the ink in the pressure chamber 13A is ejected from the nozzle 11a by displacing the partition wall portion between the adjacent pressure chambers 13A by applying a voltage to the drive electrode 14 of the pressure chamber 13A. It has become.

  In addition, the ink in each pressure chamber 13A is ejected from the nozzle 11a as described above, and also flows into the common flow passage 19 through the individual communication flow passage 18 together with the air bubbles, and then the discharge flow passage 13B and the discharge liquid. The ink is discharged to the outside of the inkjet head 100 through the chamber 57 and the fourth ink port 56. That is, in the present embodiment, the discharge flow path 13B, the discharge liquid chamber 57, and the fourth ink port 56 function as a flow path that discharges ink from the common flow path 19 to the outside of the inkjet head 100. There is.

  To the fourth ink port 56 of the inkjet head 100, a circulation flow path 203 that supplies the ink discharged from the fourth ink port 56 to the sub tank 202 is connected. The ink discharged from the fourth ink port 56 is supplied to the sub tank 202 through the circulation flow path 203, and then separated from the bubbles and reused.

[Technical effects of the present invention]
As described above, the inkjet head 100 of the present invention includes the nozzle layer 11 in which the nozzles 11a are formed, and the pressure chamber layer 12 in which the plurality of pressure chambers 13A that are stacked on the nozzle layer 11 are formed. 100 is formed in at least one of the portion of the nozzle layer 11 facing the pressure chamber layer 12 and the portion of the pressure chamber layer 12 facing the nozzle layer 11, and communicates with each of the plurality of pressure chambers 13A. A plurality of individual communication flow paths 18 capable of discharging ink of 13A, a common flow path 19 in which the plurality of individual communication flow paths 18 are connected, and the ink discharged from the plurality of individual communication flow paths 18 joins, and a common flow path A discharge channel 13B communicating with the channel 19 and capable of discharging ink from the common channel 19 to the outside of the pressure chamber layer 12, and the common channel 19 is a channel in the direction in which the ink is discharged. Sectional area has a narrower aperture portion 19a, the throttle portion 19a is connected to a discharge flow path 13B. When the narrowed portion 19a is formed, the flow velocity in the common flow passage 19 can be increased, so that the accumulation of precipitates and bubbles in the ink in the common flow passage 19 can be reduced. Further, the configuration of the diaphragm portion 19a of the present invention can be preferably applied to the small inkjet head 100, and bubbles and the like can be effectively discharged.

  Further, it is preferable that the common channel 19 is provided at least in a portion of the pressure chamber layer 12 that faces the nozzle layer 11. As a result, a large volume of the common flow path 19 for discharging ink can be secured, and bubbles or the like can be effectively discharged. Further, it is not necessary to increase the number of separate members for providing the common flow passage 19, and the large volume of the common flow passage 19 can be secured by a method that can be downsized. Further, by providing the common channel 19 having a large volume, the circulation amount of the ink in the head chip 1 can be increased, so that the heat dissipation of the head chip 1 can be effectively performed.

  In addition, the width of the common channel 19 in the ink ejection direction (vertical direction) is made larger than the thickness of the nozzle layer 11, so that the volume of the channel is larger than that when the common channel 19 is provided only in the nozzle layer 11. Can be increased.

  Further, it is preferable that the narrowed portion 19a is provided outside the individual communication flow passage 18a provided at the end of the common flow passage 19 in the ink discharge direction. As a result, the flow velocity of the ink is less likely to change near the area where the individual communication flow passage 18 is provided, so that it is possible to reduce the influence on the ejection of the ink by increasing the flow velocity of the ink in the common flow passage 19.

  Further, it is preferable that the narrowed portion 19a is formed so that its cross-sectional area gradually decreases in the direction in which the ink is discharged. As a result, bubbles are less likely to be caught on the wall surface of the common flow path 19, so that precipitates and bubbles in the ink can be efficiently discharged together with the ink.

  The discharge flow path 13B is a flow path that can discharge ink from the common flow path 19 toward the side opposite to the nozzle layer 11, and the cross-sectional area of the discharge flow path 13B is smaller than the maximum cross-sectional area of the common flow path. Is also preferably large. As a result, the flow resistance of the head chip 1 as a whole can be lowered and the ink discharge efficiency can be improved.

  Further, the common flow path 19 is preferably a linear flow path. As a result, it is possible to effectively discharge precipitates, bubbles, etc. in the ink together with the ink.

  Further, it is preferable that at least one end of the common channel 19 is sealed by the narrowed portion 19a. Thereby, the common channel 19 can be sealed only by joining the nozzle layer 11 and the pressure chamber layer 12.

  In addition, by providing the sealing member 12c at at least one end portion of the common channel 19 in the longitudinal direction (left-right direction) of the head chip 1, when forming the common channel 19, the common channel 19 is formed. Since it can be manufactured so as to penetrate to the side surface portion in the longitudinal direction of the passage 19, it can be manufactured by a method with high manufacturing efficiency.

  In addition, since the manifold 5 is provided above the pressure chamber 13A, the ink can be supplied and discharged collectively at the top of the pressure chamber 13A, so that the inkjet head 100 can be further downsized.

  Further, the ink jet recording apparatus 200 is provided with the ink jet head 100 of the present embodiment and the ink circulation means for generating the circulation flow from the pressure chamber 13A to the individual communication flow paths 18, so that the pressure chamber 13A and the pressure chamber 13A can be obtained. It is possible to provide the inkjet recording apparatus 200 that can discharge bubbles and the like existing near the nozzles 11a together with the ink to the outside of the inkjet head 100.

  Further, it is preferable to form the common flow path 19 by scanning the pressure chamber layer with a dicing blade. Further, when forming the common flow path 19, it is preferable to form the narrowed portion 19a in the common flow path 19 by moving the dicing blade so as to be shallow in the thickness direction while scanning. By the method using the dicing blade, the common flow path 19 and the narrowed portion 19a can be easily formed with high accuracy.

[Other]
The embodiments of the present invention described above are to be considered as illustrative in all points and not restrictive. That is, the scope of the present invention is shown not by the above description but by the scope of the claims, and is intended to include meanings equivalent to the scope of the claims and all modifications within the scope.

  For example, as the inkjet recording apparatus 200, the one-pass drawing type inkjet recording apparatus 200 using the line head has been described, but the scanning type inkjet recording apparatus 200 may be used.

Further, the embodiment in which the head chip 1 has two nozzle rows has been described, but the number and arrangement of the nozzles 11a can be appropriately changed, and may be one row or three or more rows, for example.
Further, although two discharge flow paths 13B are provided on the right side of the pressure chamber layer 12, the discharge flow paths may be connected to provide only one. Further, not only the right side but also the left side, the discharge flow path 13B may be provided.

  Although the ink circulation mechanism 8 has been described with reference to FIG. 20, the circulation flow from the pressure chamber 13A to the individual communication flow path 18 is generated, and the ink in the pressure chamber 13A is discharged from the discharge flow path 13B to the outside of the head chip. The structure can be changed as appropriate as long as it can be discharged.

  Further, as the head unit 224, the head unit 224 in which a pair of the pair of inkjet heads 100 adjacent to each other in the front-rear direction is arranged in a zigzag pattern at different positions in the front-rear direction has been described. It is possible.

  Further, as shown in FIG. 12 and the like, the narrowed portion 19a shows an example in which the cross-sectional area gradually decreases in the ink ejection direction, but the cross-sectional area decreases in the ink ejection direction. The upper surface may be provided in a stepped shape.

  Further, although the pressure chamber 13A and the discharge channel 13B of the head chip 1 have been described as a straight type that opens on the upper and lower surfaces of the head chip, the pressure chamber 13A and the discharge flow path 13B open on the lower surface of the head chip 1 and curve toward the upper side. The shape may be opened on the side surface of the.

1 head chip 5 manifold 8 ink circulation mechanism (ink circulation means)
11 Nozzle Layer 11a Nozzle 12 Pressure Chamber Layer 12c Sealing Member 13A Pressure Chamber 13B Discharge Flow Path 18 Individual Communication Flow Path 19 Common Flow Path 19a Throttle Portion 100 Inkjet Head 200 Inkjet Recording Device

Claims (13)

A nozzle layer having a plurality of nozzles for ejecting ink,
A pressure chamber layer that is laminated on the nozzle layer, communicates with each of the plurality of nozzles, and has a plurality of pressure chambers that store ink to be ejected from the plurality of nozzles;
An inkjet head for ejecting ink by applying pressure to the pressure chamber,
It is formed in at least one of a portion of the nozzle layer facing the pressure chamber layer and a portion of the pressure chamber layer facing the nozzle layer, communicates with each of the plurality of pressure chambers, and discharges ink from the pressure chambers. Multiple individual communication channels possible,
A plurality of individual communication channels are connected, and a common channel where the ink discharged from the plurality of individual communication channels merges,
A discharge flow path communicating with the common flow path, capable of discharging ink from the common flow path to the outside of the pressure chamber layer,
The common flow path has a narrowed portion in which the cross-sectional area of the flow path becomes narrower in the direction in which ink is discharged, and the narrowed portion is connected to the discharge flow path ,
The common flow path, the ink-jet head characterized by straight passages der Rukoto.   A nozzle layer having a plurality of nozzles for ejecting ink,
  A pressure chamber layer that is laminated on the nozzle layer, communicates with each of the plurality of nozzles, and has a plurality of pressure chambers that store ink to be ejected from the plurality of nozzles;
  An inkjet head for ejecting ink by applying pressure to the pressure chamber,
  It is formed in at least one of a portion of the nozzle layer facing the pressure chamber layer and a portion of the pressure chamber layer facing the nozzle layer, communicates with each of the plurality of pressure chambers, and discharges ink from the pressure chambers. Multiple individual communication channels possible,
  A plurality of individual communication channels are connected, and a common channel where the ink discharged from the plurality of individual communication channels merges,
  A discharge flow path communicating with the common flow path, capable of discharging ink from the common flow path to the outside of the pressure chamber layer,
  The common flow path has a narrowed portion in which the cross-sectional area of the flow path becomes narrower in the direction in which ink is discharged, and the narrowed portion is connected to the discharge flow path,
  An inkjet head, wherein at least one end of the common flow path is sealed by the throttle portion.   A nozzle layer having a plurality of nozzles for ejecting ink,
  A pressure chamber layer that is laminated on the nozzle layer, communicates with each of the plurality of nozzles, and has a plurality of pressure chambers that store ink to be ejected from the plurality of nozzles;
  An inkjet head for ejecting ink by applying pressure to the pressure chamber,
  It is formed in at least one of a portion of the nozzle layer facing the pressure chamber layer and a portion of the pressure chamber layer facing the nozzle layer, communicates with each of the plurality of pressure chambers, and discharges ink from the pressure chambers. Multiple individual communication channels possible,
  A plurality of individual communication channels are connected, and a common channel where the ink discharged from the plurality of individual communication channels merges,
  A discharge flow path communicating with the common flow path, capable of discharging ink from the common flow path to the outside of the pressure chamber layer,
  The common flow path has a narrowed portion in which the cross-sectional area of the flow path becomes narrower in the direction in which ink is discharged, and the narrowed portion is connected to the discharge flow path,
  The inkjet head is characterized in that a sealing member for sealing the common flow path is provided at at least one end of the common flow path. The inkjet head according to any one of claims 1 to 3 , wherein the common flow path is provided at least in a portion of the pressure chamber layer that faces the nozzle layer. The inkjet head according to claim 4 , wherein the width of the common flow path in the ink ejection direction is larger than the thickness of the nozzle layer. The throttle unit, wherein, characterized in that the front Symbol ink in the common flow path is provided in the discharge direction of the ink than the individual communication passage provided in the most discharge direction side in the direction to be discharged The inkjet head according to any one of claims 1 to 5 . The inkjet section according to any one of claims 1 to 6 , wherein the narrowed portion is formed so that a cross-sectional area thereof gradually decreases in a direction in which the ink is discharged. head. The discharge channel is a channel capable of discharging ink from the common channel toward the side opposite to the nozzle layer,
The inkjet head according to any one of claims 1 to 7 , wherein a cross-sectional area of the discharge channel is larger than a maximum cross-sectional area of the common channel. A manifold for storing ink to be supplied to the plurality of pressure chambers,
The inkjet head according to any one of claims 1 to 8 , wherein the manifold is provided on an upper portion of the pressure chamber opposite to the nozzle layer side . An inkjet head according to any one of claims 1 to 9 ,
Ink circulation means for generating a circulation flow from the pressure chamber to the individual communication flow path,
An inkjet recording apparatus comprising: A method for manufacturing an inkjet head according to any one of claims 1 to 9 ,
A method for manufacturing an inkjet head, wherein the common flow path is formed by scanning a dicing blade on the pressure chamber layer.   A nozzle layer having a plurality of nozzles for ejecting ink,
  A pressure chamber layer that is laminated on the nozzle layer, communicates with each of the plurality of nozzles, and has a plurality of pressure chambers that store ink to be ejected from the plurality of nozzles;
  An inkjet head for ejecting ink by applying pressure to the pressure chamber,
  It is formed in at least one of a portion of the nozzle layer facing the pressure chamber layer and a portion of the pressure chamber layer facing the nozzle layer, communicates with each of the plurality of pressure chambers, and discharges ink from the pressure chambers. Multiple individual communication channels possible,
  A plurality of individual communication channels are connected, and a common channel where the ink discharged from the plurality of individual communication channels merges,
  A discharge flow path communicating with the common flow path, capable of discharging ink from the common flow path to the outside of the pressure chamber layer,
  The method for manufacturing an inkjet head, wherein the common flow channel has a narrowed portion in which a cross-sectional area of the flow channel becomes narrower in a direction in which ink is discharged, and the narrowed portion is connected to the discharge flow channel. ,
  A method for manufacturing an inkjet head, wherein the common flow path is formed by scanning a dicing blade on the pressure chamber layer. When forming the common flow path, the dicing blade is moved so as to be shallow in the thickness direction while scanning, and the narrowed portion is formed in the common flow path. 11. The method for manufacturing an inkjet head described in 11 or 12.

Images