JPWO2013105403A1 - Inkjet head - Google Patents

Abstract

In an inkjet head having three or more channel rows, in order to ensure that the channel can be sealed with an adhesive, three or more channel rows are arranged in parallel, and the drive channel 11a and the dummy channel 11b Are arranged so that the end portion of the head chip 1 protrudes from the side of the head chip 1 with respect to the rear surface 1b of the head chip 1. An ink-jet head having a wiring substrate 3 that electrically pulls out the drive electrode to the end via the connection electrode and the wiring electrode 32 and closes the opening of the dummy channel 11b. At least one of the dummy channel 11b and the drive channel 11a in at least one channel row located inside three or more channel rows arranged in parallel Connecting electrodes of the square of the channel, characterized in that it is formed so as to surround the opening of the channel.

Description

  The present invention relates to an ink jet head, and more particularly to an ink jet head capable of satisfactorily penetrating an adhesive between a head chip having three or more channel rows and a wiring board bonded to the rear surface thereof.

  By applying a drive signal of a predetermined voltage to the drive electrode formed on the surface of the drive wall that defines the channel, the drive wall is subjected to shear deformation, and the pressure generated when the volume of the channel changes is utilized to 2. Description of the Related Art As a shear mode type ink jet head that discharges ink from nozzles, one having a so-called harmonica type head chip in which opening portions of channels are respectively arranged on a front surface and a rear surface is known.

  In the harmonica type head chip, the drive electrode faces the channel and is not exposed to the outside. Therefore, the drive electrode is joined to the rear surface side of the head chip by using this substrate to drive each drive electrode. Is electrically pulled out of the head chip.

  For example, in Patent Document 1, an electrical contact is formed on the rear surface of a harmonica type head chip having a plurality of channel rows by exposing end portions of drive electrodes in the channel, and a flexible substrate is formed on the rear surface. It is disclosed that each drive electrode is electrically drawn out through the wiring board by bonding the wiring board made of the above. The wiring board has an ink flow path opening at a position corresponding to each channel, and the ink in the manifold bonded to the rear surface side of the wiring board can be individually supplied into each channel through the ink flow path opening. I am doing so.

Japanese Patent Laid-Open No. 2002-178509 (FIG. 18)

  As shown in FIG. 18, such a harmonica type head chip includes a long wafer 100 formed so that a plurality of channel rows in which channels and drive walls are alternately arranged are arranged in parallel. It is mounted on 200, and is cut by a dicing blade 300 along a direction orthogonal to the length direction of the channel so that the channel length becomes a desired length, and is manufactured by full cutting. The full cut is performed by lowering the dicing blade 300 rotating from the upper surface of the wafer 100 and gradually digging it. Usually, a plurality of head chips 400 are cut out from one wafer 100. In the figure, reference numeral 101 denotes a full cut portion.

  In this full cut operation, as the depth when the dicing blade 300 is dug deeper, a phenomenon occurs in which the groove width of the full cut portion 101 becomes narrower, and a vertical cut surface cannot be formed. As a result, the cut cross section of the cut out head chip 400 is in a state in which a so-called edge stands at the side edge e1 which is the deepest portion. Usually, this side edge e1 is one side edge of two side edges along the length direction of the channel row (hereinafter referred to as channel row direction) at the four side edges around the cutting cross section of the head chip 1. It is.

  Since the width of the dicing blade 300 itself is not tapered, the cause of the edge standing in this way is unknown, but the cutting depth increases (the thickness of the wafer 100 increases). It becomes difficult to maintain the flatness of the cross section. As a result of confirmation by the present inventors, when the wafer 100 having a thickness of 4.6 mm was fully cut, the maximum protrusion amount d of the side edge e1 was about 2 to 5 μm. In particular, when the head chip 400 has a plurality of channel rows of three or more rows, the wafer 100 is also thick, and thus the edge e1 with the edge standing is likely to be formed.

  When the edge of one side edge 1e is thus standing, the cutting cross section of the head chip 400 coincides with a plane P passing through the side edge e1 and the other side edge e2, as shown in FIG. This is not a flat surface, but is a surface having a concave shape between both side edges e1 and e2 with respect to the plane P, which causes the following problems.

  As shown in FIG. 20, the harmonica type head chip 400 has connection electrodes 402 that are electrically connected to the drive electrodes in the respective channels 401 on the rear surface 400a (the surface opposite to the surface in the ink ejection direction). Is arranged. The head chip 400 shown here has four channel rows 400A to 400D, and in each of the channel rows 400A to 400D, drive channels 401a that discharge ink and dummy channels 401b that do not discharge ink are alternately arranged. This is an independent drive type head chip.

  On the other hand, as shown in FIG. 21, the wiring substrate 500 bonded to the rear surface 400a of the head chip 400 has an ink flow path port 501 for supplying ink to the drive channel at a position corresponding to the drive channel. Yes. Since it is not necessary to supply ink to the dummy channel, nothing is formed in the portion of the wiring substrate 500 at a position corresponding to the dummy channel, and the dummy channel is closed by the wiring substrate 500. Wiring electrodes 502 are formed on the wiring substrate 500 so as to correspond to the connection electrodes 402 on the head chip 400 side, respectively.

  When such a wiring substrate 500 is bonded to the rear surface 400a of the head chip 400, a conductive adhesive X containing metal particles is used for electrical connection between the connection electrode 402 and the wiring electrode 502, and the connection electrode, the wiring electrode, and the like. Are applied so as to form a belt-like region over the overlapping portion, and then bonded by aligning the two. At this time, since the adhesive X is not directly applied to the periphery of the dummy channel, the adhesive X applied to the band-like region is used by utilizing a slight gap formed between the head chip 400 and the wiring substrate 500. It is necessary to infiltrate by capillary force and seal the periphery of the openings of all the dummy channels 401b with the adhesive X. If the opening of the dummy channel 401b is not completely sealed, the ink is allowed to enter, and the deformation operation of the drive wall 403 shared between the adjacent drive channels 401a is hindered, so that the drive channel 401a This is because ejection may be hindered, and the droplet speed may be slowed or ejection may not be possible.

  However, as described above, the distance between the inner channel rows 400B and 400C and the wiring substrate 500 is caused by the fact that the rear surface 400a becomes a concave surface with the edge of the side edge e1 standing. As a result, as shown in FIG. 22, the adhesive X does not permeate due to the capillary force at the inner channel rows 400B and 400C, and the dummy channel opening is formed. There is a problem that the periphery of the portion cannot be surrounded by the adhesive X, and the dummy channel cannot be sealed. Such a problem occurs depending on the bonding state even when the wiring substrate 500 is a relatively flexible substrate such as an FPC, but when the wiring substrate 500 is made of a hard substrate material such as glass, ceramics, or silicon. This is a particularly noticeable problem.

  In addition, even in a head chip that uses all channels in the channel row as drive channels, ink throttle holes for narrowing the flow paths of ink supplied to the channels corresponding to the channels are individually provided on the wiring board. In some cases, the flow path resistance is increased, and even a low-viscosity ink can be stably ejected. In this case as well, it is necessary to prevent ink leakage by sealing the periphery of the ink squeeze hole with an adhesive, which causes the same problem as described above. Therefore, even in a head chip in which all the channels in the channel row are drive channels, there is a serious problem that the adhesive does not permeate due to capillary force in the channel row inside the plurality of channel rows.

  In view of this, the present invention provides an independent flow type head chip having three or more channel rows each composed of a drive channel that discharges ink and a dummy channel that does not discharge ink, so that the ink flow path opening is compatible with only each drive channel. It is an object of the present invention to make it possible to reliably perform channel sealing with an adhesive in an ink jet head configured by bonding wiring substrates formed with the adhesive.

  In addition, the present invention is configured by joining a wiring board having ink squeeze holes to each channel to a head chip having three or more channel rows that are drive channels for discharging ink from all channels. It is an object of the present invention to make it possible to reliably seal the periphery of an ink throttle hole with an adhesive.

  Other problems of the present invention will become apparent from the following description.

  The above problems are solved by the following inventions.

1. Three or more channel rows in which channels and drive walls made of piezoelectric elements are alternately arranged are arranged side by side, drive electrodes are respectively formed on the drive walls facing the channels, and openings of the channels are formed on the front and rear surfaces. And a connection electrode that is electrically connected to the drive electrode through the opening is formed on the rear surface. The channel row includes a drive channel that performs ink discharge and a dummy channel that does not discharge ink. Alternately arranged head chips,
In addition to having ink flow path openings individually corresponding to the drive channels and wiring electrodes respectively corresponding to the connection electrodes, an end portion protrudes from the side of the head chip with respect to the rear surface of the head chip. When the connection electrode and the wiring electrode are electrically connected to each other, the drive electrode is electrically drawn out to the end portion through the connection electrode and the wiring electrode, and the opening of the dummy channel An inkjet head comprising a wiring board for closing
The head chip includes the connection electrode of at least one of the dummy channel and the drive channel in at least one of the channel rows located inside the channel row arranged in parallel with three or more rows. Is formed so as to surround the opening of the channel.

2. The wiring board has an end portion of the wiring electrode corresponding to the dummy channel of the channel row located at least inside of the channel rows arranged in parallel in the head chip, wherein the end portion of the dummy channel 2. The ink jet head as described in 1 above, wherein the ink jet head is formed so as to surround a region corresponding to the opening, or to surround and cover an inner region.

3. In the wiring board, an end portion of the wiring electrode corresponding to the drive channel of the channel row located at least inside of the channel rows arranged in parallel in the head chip corresponds to the drive channel. 3. The inkjet head according to 1 or 2, wherein the inkjet head is formed so as to surround the ink flow path opening.

4). Three or more channel rows in which channels and drive walls made of piezoelectric elements are alternately arranged are arranged side by side, drive electrodes are respectively formed on the drive walls facing the channels, and openings of the channels are formed on the front and rear surfaces. And a connection electrode that is electrically connected to the drive electrode through the opening is formed on the rear surface. The channel row includes a drive channel that performs ink discharge and a dummy channel that does not discharge ink. Alternately arranged head chips,
In addition to having ink flow path openings individually corresponding to the drive channels and wiring electrodes respectively corresponding to the connection electrodes, an end portion protrudes from the side of the head chip with respect to the rear surface of the head chip. When the connection electrode and the wiring electrode are electrically connected to each other, the drive electrode is electrically drawn out to the end portion through the connection electrode and the wiring electrode, and the opening of the dummy channel An inkjet head comprising a wiring board for closing
The head chip is formed such that the connection electrode of only the dummy channel in at least one of the channel rows located inside the channel row arranged in parallel with three or more rows surrounds the opening. And
In the wiring substrate, an end portion of the wiring electrode corresponding only to the driving channel in the channel row including the dummy channel formed so that the connection electrode surrounds the opening corresponds to the driving channel. An ink jet head formed so as to surround an ink flow path opening.

5. Three or more channel rows in which channels and drive walls made of piezoelectric elements are alternately arranged are arranged side by side, drive electrodes are respectively formed on the drive walls facing the channels, and openings of the channels are formed on the front and rear surfaces. And a connection electrode that is electrically connected to the drive electrode through the opening is formed on the rear surface. The channel row includes a drive channel that performs ink discharge and a dummy channel that does not discharge ink. Alternately arranged head chips,
In addition to having ink flow path openings individually corresponding to the drive channels and wiring electrodes respectively corresponding to the connection electrodes, an end portion protrudes from the side of the head chip with respect to the rear surface of the head chip. When the connection electrode and the wiring electrode are electrically connected to each other, the drive electrode is electrically drawn out to the end portion through the connection electrode and the wiring electrode, and the opening of the dummy channel An inkjet head comprising a wiring board for closing
The head chip is formed such that the connection electrode of only the drive channel in at least one channel row located inside the channel row arranged in parallel with three or more rows surrounds the opening. And
In the wiring substrate, an end portion of the wiring electrode corresponding to only the dummy channel in the channel row including the drive channel formed so that the connection electrode surrounds the opening is formed in the opening of the dummy channel. An ink jet head characterized in that it is formed so as to surround a region corresponding to, or to surround and cover an inner region.

6). Three or more channel rows in which channels and drive walls made of piezoelectric elements are alternately arranged are arranged side by side, drive electrodes are respectively formed on the drive walls facing the channels, and openings of the channels are formed on the front and rear surfaces. And a connection electrode that is electrically connected to the drive electrode through the opening is formed on the rear surface. The channel row includes a drive channel that performs ink discharge and a dummy channel that does not discharge ink. Alternately arranged head chips,
In addition to having ink flow path openings individually corresponding to the drive channels and wiring electrodes respectively corresponding to the connection electrodes, an end portion protrudes from the side of the head chip with respect to the rear surface of the head chip. When the connection electrode and the wiring electrode are electrically connected to each other, the drive electrode is electrically drawn out to the end portion through the connection electrode and the wiring electrode, and the opening of the dummy channel An inkjet head comprising a wiring board for closing
The wiring board has an end portion of the wiring electrode corresponding to the dummy channel of the channel row located at least inside of the channel rows arranged in parallel in the head chip, wherein the end portion of the dummy channel An inkjet head characterized by surrounding an area corresponding to an opening or surrounding and covering an inner area.

7). In the wiring board, an end portion of the wiring electrode corresponding to the drive channel of the channel row located at least inside of the channel rows arranged in parallel in the head chip corresponds to the drive channel. 7. The ink jet head as described in 6 above, wherein the ink jet head is formed so as to surround the ink flow path opening.

8). Three or more channel rows in which channels and drive walls made of piezoelectric elements are alternately arranged are arranged side by side, drive electrodes are respectively formed on the drive walls facing the channels, and openings of the channels are formed on the front and rear surfaces. And a connection electrode that is electrically connected to the drive electrode through the opening is formed on the rear surface. The channel row includes a drive channel that performs ink discharge and a dummy channel that does not discharge ink. Alternately arranged head chips,
In addition to having ink flow path openings individually corresponding to the drive channels and wiring electrodes respectively corresponding to the connection electrodes, an end portion protrudes from the side of the head chip with respect to the rear surface of the head chip. When the connection electrode and the wiring electrode are electrically connected to each other, the drive electrode is electrically drawn out to the end portion through the connection electrode and the wiring electrode, and the opening of the dummy channel An inkjet head comprising a wiring board for closing
In the wiring board, an end portion of the wiring electrode corresponding to the drive channel of the channel row located at least inside of the channel rows arranged in parallel in the head chip corresponds to the drive channel. An ink-jet head formed so as to surround the ink flow path opening.

9. The wiring board has at least one wiring electrode between adjacent ink flow path openings in at least one of the ink flow path opening rows among the plurality of ink flow path opening rows corresponding to the channel rows. The inkjet head according to any one of 1 to 8, wherein the inkjet head extends to an end portion protruding from a side of the head chip.

10. Three or more channel rows in which channels and drive walls made of piezoelectric elements are alternately arranged are arranged side by side, drive electrodes are respectively formed on the drive walls facing the channels, and openings of the channels are formed on the front and rear surfaces. Each of which is disposed, and on the rear surface thereof, a connection electrode that is electrically connected to the drive electrode is formed through the opening, and the channel row is configured by drive channels in which all the channels discharge ink. A head chip,
In addition to the ink restriction holes for restricting the flow paths of the ink supplied to the channels individually corresponding to the channels, and wiring electrodes corresponding to the connection electrodes, respectively, an end portion with respect to the rear surface of the head chip Are connected so as to protrude from the side of the head chip, and the connection electrode and the wiring electrode are electrically connected, so that the drive electrode is connected to the end portion through the connection electrode and the wiring electrode. An ink jet head having a wiring board that is electrically drawn out,
The head chip is formed such that the connection electrode of the channel in at least one of the channel rows located inside the channel row arranged in parallel with three or more rows surrounds the opening of the channel. An ink jet head characterized by comprising:

11. In the wiring substrate, an end portion of the wiring electrode corresponding to the channel of the channel row located at least inside of the channel rows arranged in parallel in three or more rows in the head chip is formed in the opening of the channel. 11. The ink jet head as described in 10 above, wherein the ink jet head is formed so as to surround a region corresponding to, or to surround and surround the ink squeeze hole inside the region.

12 Three or more channel rows in which channels and drive walls made of piezoelectric elements are alternately arranged are arranged side by side, drive electrodes are respectively formed on the drive walls facing the channels, and openings of the channels are formed on the front and rear surfaces. Each of which is disposed, and on the rear surface thereof, a connection electrode that is electrically connected to the drive electrode is formed through the opening, and the channel row is configured by drive channels in which all the channels discharge ink. A head chip,
In addition to the ink restriction holes for restricting the flow paths of the ink supplied to the channels individually corresponding to the channels, and wiring electrodes corresponding to the connection electrodes, respectively, an end portion with respect to the rear surface of the head chip Are connected so as to protrude from the side of the head chip, and the connection electrode and the wiring electrode are electrically connected, so that the drive electrode is connected to the end portion through the connection electrode and the wiring electrode. An ink jet head having a wiring board that is electrically drawn out,
In the head chip, the connection electrodes of every other channel in the at least one channel row located inside the channel row arranged in parallel with three or more rows surround the opening of the channel. And is formed as
The wiring board is formed so that the connection electrodes of every other channel in the head chip surround the opening of the channel, and the connection electrodes in the channel row surround the opening. An end portion of the wiring electrode corresponding to the non-channel is formed so as to surround the region corresponding to the opening of the channel or to cover the surrounding area of the ink squeeze hole inside the channel. An inkjet head characterized by that.

13. Three or more channel rows in which channels and drive walls made of piezoelectric elements are alternately arranged are arranged side by side, drive electrodes are respectively formed on the drive walls facing the channels, and openings of the channels are formed on the front and rear surfaces. Each of which is disposed, and on the rear surface thereof, a connection electrode that is electrically connected to the drive electrode is formed through the opening, and the channel row is configured by drive channels in which all the channels discharge ink. A head chip,
In addition to the ink restriction holes for restricting the flow paths of the ink supplied to the channels individually corresponding to the channels, and wiring electrodes corresponding to the connection electrodes, respectively, an end portion with respect to the rear surface of the head chip Are connected so as to protrude from the side of the head chip, and the connection electrode and the wiring electrode are electrically connected, so that the drive electrode is connected to the end portion through the connection electrode and the wiring electrode. An ink jet head having a wiring board that is electrically drawn out,
In the wiring substrate, an end portion of the wiring electrode corresponding to the channel of the channel row located at least inside of the channel rows arranged in parallel in three or more rows in the head chip is formed in the opening of the channel. The inkjet head is formed so as to surround a region corresponding to, or to cover and surround the ink squeeze hole inside and surrounding the region.

14 The wiring board includes at least one wiring electrode between adjacent ink throttling holes in at least one ink throttling hole row among the plurality of ink throttling hole rows corresponding to the channel row. 14. The ink jet head according to any one of 10 to 13, wherein the ink jet head extends to an end portion protruding from a side of the head chip.

15. The inkjet head according to any one of 1 to 14, wherein the wiring board is made of any one of glass, ceramics, and silicon.

16. 16. The inkjet head according to any one of 1 to 15, wherein a rear surface of the head chip is recessed with respect to a plane passing through two side edges along the channel row direction.

17. A space where the connection electrode does not exist is formed between the ends of the connection electrodes of the two outermost channel rows of the head chip and the side edges of the rear surface of the head chip, and 3 The thickness of the connection electrode of the inner channel row of the channel rows equal to or higher than the row is higher than the position of the plane passing through the two side edges along the channel row direction of the head chip from the rear surface of the head chip. 17. The inkjet head as described in 16 above, wherein the inkjet head is formed so as to be high.

  According to the present invention, an ink flow channel opening is provided so as to correspond to each drive channel only in an independent drive type head chip having three or more channel rows each composed of a drive channel that performs ink ejection and a dummy channel that does not eject ink. In the ink jet head configured by bonding the wiring substrates on which the film is formed, the channel can be reliably sealed with the adhesive.

  In addition, according to the present invention, a wiring board having an ink throttle hole formed on each channel is bonded to a head chip having three or more channel rows that are drive channels for discharging ink from all channels. In the inkjet head configured, the periphery of the ink squeeze hole can be reliably sealed with an adhesive.

1 is an exploded perspective view showing a first embodiment of an inkjet head according to the present invention. 1 is a rear view of the head chip of the ink jet head shown in FIG. The figure explaining the state of the joint surface of a head chip and a wiring board Sectional view along line (iv)-(iv) in FIG. The front view which shows the other aspect of the wiring board in the inkjet head shown in 1st Embodiment. The figure which shows the part of the further another aspect of the wiring board in the inkjet head shown in 1st Embodiment. The figure which shows the end of the wiring electrode of the further another aspect of the wiring board in the inkjet head shown in 1st Embodiment. The figure which shows the part of the further another aspect of the wiring board in the inkjet head shown in 1st Embodiment. The figure which shows the part of the other aspect of the head chip in the inkjet head shown in 1st Embodiment, and a wiring board. The figure which shows the part of the other aspect of the head chip in the inkjet head shown in 1st Embodiment, and a wiring board. FIG. 3 is an exploded perspective view showing a second embodiment of the inkjet head according to the present invention. The rear view of the head chip of the inkjet head shown in FIG. The front view which shows the other aspect of the wiring board in the inkjet head shown in 2nd Embodiment. The figure which shows the part of the further another aspect of the wiring board in the inkjet head shown in 2nd Embodiment. The figure which shows the end of the wiring electrode of the further another aspect of the wiring board in the inkjet head shown in 2nd Embodiment. The figure which shows the part of the further another aspect of the wiring board in the inkjet head shown in 2nd Embodiment. The other aspect of the wiring pattern of the wiring electrode of a wiring board is shown, (a) is the surface of a wiring board, (b) is a figure which shows the back surface of a wiring board Explanatory drawing of head chip manufacturing method 18 is a longitudinal sectional view of a head chip obtained by the manufacturing method of FIG. Rear view of conventional head chip Front view of a conventional wiring board coated with adhesive The figure explaining the state of the joint surface of the conventional head chip and a wiring board

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(First embodiment: independent drive type)
FIG. 1 is an exploded perspective view showing a first embodiment of an ink jet head according to the present invention, and FIG. 2 is a rear view of a head chip of the ink jet head shown in FIG.

  In the figure, H1 is an inkjet head, 1 is a head chip, 2 is a nozzle plate, 3 is a wiring board, and 4 is a manifold.

  The head chip 1 is composed of a hexahedron having a front surface 1a and a rear surface 1b and four side surfaces, upper, lower, left and right, sandwiched between the front surface 1a and the rear surface 1b. A large number of channels 11a and 11b and drive walls 12 made of piezoelectric elements are alternately arranged to form one channel row. Here, four channel rows 10A to 10D are provided, and these are arranged in parallel in the vertical direction in FIG.

  In the head chip 1, in each of the channel rows 10A to 10D, independent drive in which drive channels 11a that supply ink and discharge ink and dummy channels 11b that do not supply ink and discharge ink are alternately arranged. This is a type of head chip.

  Such a head chip 1 is a so-called harmonica type head chip of a shear mode type generally having a hexahedral shape. Each of the channels 11a and 11b is formed in a straight shape that opens to the front surface 1a and the rear surface 1b. The opening on the front surface 1a side is an ink outlet, and the opening on the rear surface 1b side is an ink inlet. Hereinafter, when simply referred to as an opening portion of a channel, it refers to an ink inlet opening on the rear surface 1b side.

  In this specification, the “front surface” of the head chip 1 refers to the surface on the side where the nozzles are arranged and ink is ejected, and the “rear surface” refers to the surface on the opposite side.

  As shown in FIG. 18, the head chip 1 is manufactured by being fully cut out from a long wafer 100 by a dicing blade 300, and one side edge e <b> 1 on the rear surface 1 b side is an edge. Is still standing. Accordingly, the rear surface 1b remains a flat surface in which the inner sides of the side edges e1 and e2 are recessed with respect to the plane passing through the two side edges e1 and e2 along the channel row direction.

  On the surface of the drive wall 12 facing the inside of each channel 11a, 11b, a drive electrode (not shown) for applying a voltage for driving the drive wall 12 to be deformed is formed by sputtering, vapor deposition, electroless plating or the like. Has been. On the rear surface 1b of the head chip 1, connection electrodes 13a and 13b that are electrically connected to the drive electrodes through the openings of the channels 11a and 11b are provided for each of the channels 11a and 11b by sputtering, vapor deposition, electroless plating, or the like. Are individually formed.

  Of the connection electrodes 13a and 13b, the connection electrodes 13a and 13a of the channels 11a and 11b of the two outermost channel rows 10A and 10D are adjacent to the side edges on the rear surface 1b from the channels 11a and 11b. It is pulled out toward e1 or e2.

  On the other hand, the connection electrodes 13b and 13b of the channels 11a and 11b of the two channel rows 10B and 10C located inside the channel rows 10B and 10C are formed so as to surround the openings of the channels 11a and 11b. That is, the openings of the channels 11a and 11b are arranged in the connection electrode 13b formed in a rectangular shape.

  In consideration of connectivity with a wiring electrode described later, the connection electrode 13b of the channel row 10B is formed so as to slightly protrude toward the adjacent outer channel row 10A, and the connection electrode 13b of the channel row 10C. Is formed so as to protrude slightly toward the adjacent outer channel row 10D.

  A nozzle plate 2 is bonded to the front surface 1 a of the head chip 1. In the nozzle plate 2, nozzles 21 are formed only at positions corresponding to the drive channels 11a.

  On the other hand, the wiring substrate 3 is bonded to the rear surface 1 b of the head chip 1. The wiring board 3 has an area larger than the area of the rear surface 1b of the head chip 1, and the end portions 3a and 3b are lateral to the head chip 1 while being bonded to the rear surface 1b of the head chip 1. It protrudes greatly (at least in the vertical direction in the figure).

  In the wiring board 3, ink for supplying the ink stored in the manifold 4 bonded to the back side of the wiring board 3 to each driving channel 11 a only at a position corresponding to the driving channel 11 a of the head chip 1. Each channel port 31 is opened individually. The ink flow path port 31 has an opening area equivalent to the opening of the drive channel 11a. In FIG. 1, 31 </ b> A to 31 </ b> D indicate rows of ink flow path ports 31 corresponding to the channel rows 10 </ b> A to 10 </ b> D of the head chip 1.

  Further, the portion of the wiring board 3 corresponding to the dummy channel 11b closes the opening of the dummy channel 11b by the board itself.

  A wiring electrode 32 is sputtered and deposited on the surface of the wiring substrate 3 to be bonded to the head chip 1 in a one-to-one correspondence with the connection electrodes 13a and 13b arranged on the rear surface 1b of the head chip 1. Alternatively, it is formed by electroless plating or the like. One end of each wiring electrode 32 reaches the vicinity of the opening of the corresponding drive channel 11a and dummy channel 11b in a state where the head chip 1 and the wiring substrate 3 are joined, and the other end is the head chip. 1 extends to the end portions 3a and 3b of the wiring board 3 projecting sideways.

  Here, the other end of the wiring electrode 32 is distributed to the end portions 3a and 3b for every two adjacent channel rows. That is, the other end of the wiring electrode 32 corresponding to the channel rows 10A and 10B extends toward the upper end 3a in the drawing, and the other end of the wiring electrode 32 corresponding to the channel rows 10C and 10D is the lower end in the drawing. It extends toward the portion 3b.

  The wiring electrodes 32 corresponding to the two inner channel rows 10B and 10C are routed so as to reach the end portions 3a and 3b through the wiring electrodes 32 corresponding to the outer channel rows 10A and 10D, respectively. Has been. Therefore, among the plurality of ink flow path port 31 rows 31A to 31D corresponding to the channel rows 10A to 10D, the inner channel is disposed between the adjacent ink flow path ports 31 in the outer ink flow path port 31 rows 31A and 31D. Two wiring electrodes 32 corresponding to the rows 10B and 10C pass through and extend to the end portions 3a and 3b of the wiring board 3. Thereby, the wiring electrode 32 can be wired with high density.

  External wiring members 5 and 5 (see FIG. 1) such as FPC are joined to the end portions 3a and 3b of the wiring board 3, respectively, and are electrically connected to a drive circuit (not shown).

  When the wiring board 3 is bonded to the rear surface 1b of the head chip 1, an adhesive is applied to the surface of the wiring board 3 in the same manner as the adhesive X in the belt-like region shown in FIG. When a predetermined heating and pressurization are performed, the applied adhesive penetrates the gap between the head chip 1 and the wiring substrate 3 by a capillary force. At this time, since the head chip 1 is in a state where the edge of the side edge e1 is standing, the gap between the head chip 1 and the wiring board 3 is larger on the inner side than the side edges e1 and e2 side, and in particular, the inner channel rows 10B and 10C. In this part, there is a distance between the head chip 1 and the wiring board 3. However, since the connection electrode 13b is formed on the rear surface 1b of the head chip 1 so as to surround the openings of the channels 11a and 11b of the channel rows 10B and 10C, the head chip has a thickness corresponding to the thickness of the connection electrode 13b. 1 and the wiring board 3 are narrower. As a result, the adhesive X can permeate between the surface of the connection electrode 13b and the wiring board 3 by the capillary force so as to follow the shape of the connection electrode 13b.

  As a result, as shown in FIG. 3, in the portions of the respective drive channels 11a of the channel rows 10B and 10C, the periphery of the openings of the respective drive channels 11a and the corresponding ink flow path ports 31 of the wiring board 3 are arranged. The adhesive X penetrates so as to surround it, and the periphery of the opening of each drive channel 11a is sealed. Further, in the portions of the dummy channels 11b of the channel rows 10B and 10C, the adhesive X penetrates so as to surround the periphery of the opening of each dummy channel 11b, and the periphery of the opening of each dummy channel 11b is sealed. The Accordingly, ink can be prevented from entering the dummy channel 11b also in the inner channel rows 10B and 10C.

  Since the adhesive X penetrates along the shape of the connection electrode 13b, it penetrates along the periphery of the opening of the dummy channel 11b while avoiding the opening of the dummy channel 11b. In FIG. 3, a region 33 indicated by shading in a portion corresponding to the dummy channel 11b indicates a region where the adhesive X inside the opening of the dummy channel 11b is not permeated.

  The thickness of each connection electrode 13a, 13b can generally be 1 μm to 10 μm. However, the connection electrode 13b of the channel channel 10B, 10C inside the head chip 1 and the dummy channel 11b is connected to the wiring electrode 32. 4, it is preferable that the height from the rear surface 1b is higher than the position of the plane P passing through the two side edges e1 and e2, as shown in FIG. . Thereby, when joining the wiring board 3, the contact of these inner side connection electrodes 13b and the wiring electrode 32 can be made favorable, and electrical connection can be made more reliable.

  The height of the connection electrode 13b can be appropriately adjusted according to the thickness at the time of electrode formation.

  As shown in FIGS. 2 and 4, a predetermined distance is provided between the outer ends of the connection electrodes 13a of the channel rows 10A and 10D on both outer sides of the head chip 1 and the side edges e1 and e2 on the rear surface 1b. It is preferable that a space S where no connection electrode exists is formed. That is, the outer ends of the connection electrodes 13a of the channel rows 10A and 10D on both outer sides do not reach the side edges e1 and e2, and are in a range up to the front of the side edges e1 and e2 with a space S therebetween. Is formed. Thereby, when the wiring board 3 is joined, the surface of the wiring board 3 can be brought as close as possible to the side edges e1 and e2. Accordingly, the gap between the inner channel rows 10B and 10C and the wiring board 3 can be reduced, and the electrical connection between the inner connection electrode 13b and the wiring electrode 32 can be further ensured.

  As a substrate material of the wiring substrate 3, it is preferable to use any one of glass, ceramics, and silicon. Since these are all hard substrates, the wiring substrate 3 is difficult to follow the shape of the rear surface 1b when bonded to the rear surface 1b of the head chip 1 with the edge standing at the side edge e1. Therefore, a state in which there is a gap with the vicinity of the center portion of the rear surface 1b is likely to be formed, and in particular, at least one channel row on the inner side is liable to cause a sealing leak at the channel opening. Therefore, a remarkable effect can be obtained by applying the present invention.

  In the above description, the connection electrode 13b is formed so as to surround the openings of the drive channels 11a and the dummy channels 11b of the two inner channel rows 10B and 10C among the four channel rows 10A to 10D. However, in the present invention, the channel row forming the connection electrode 13b so as to surround the opening may be at least one channel row located inside the channel row arranged in parallel with three or more rows, The number of channel rows can be appropriately determined according to the standing condition of the side edge e1.

  Further, here, the most reliable sealing structure in which the connection electrode 13b is formed so as to surround the periphery of both openings of the drive channel 11a and the dummy channel 11b in the channel row is disclosed. However, in the present invention, the drive channel 11a is disclosed. The connection electrode 13b may be formed so as to surround the opening of at least one of the dummy channels 11b. Accordingly, the connection electrode 13b may be formed so as to surround the opening of only the drive channel 11a of the channel rows 10B and 10C located inside, or so as to surround the opening of only the dummy channel 11b. You may do it. In either case, the effect of preventing ink from entering the dummy channel 11b can be obtained. In this case, since the adjacent connection electrode 13b is not too close, the patterning of the connection electrode 13b becomes easy.

  Further, when there are a plurality of channel rows located inside like the channel rows 10B and 10C, for example, the channel row 10B is formed so as to surround the opening of only the drive channel 11a, and the channel row 10C is a dummy. You may form so that the opening part of only the channel 11b may be surrounded. Also in this case, since the connection electrode 13b is not too close on the rear surface 1b of the head chip 1, the patterning of the connection electrode 13b is facilitated.

  In the above embodiment, the wiring board 3 is not provided with any means for assisting the penetration of the adhesive X for sealing the dummy channel 11b. However, the connection electrode 13b as described above is provided on the head chip 1. In addition to the formation, a means for assisting the penetration of the adhesive X for sealing the dummy channel 11b can also be provided in the wiring board 3.

  FIG. 5 is a front view of the wiring board 3 provided with a means for assisting the penetration of the adhesive X for sealing the dummy channel 11b from the surface. The parts denoted by the same reference numerals as those in FIG. 1 and FIG.

  The wiring board 3 surrounds a region corresponding to only the opening of the dummy channel 11b at one end of each wiring electrode 32 corresponding to the connection electrode 13b of each dummy channel 11b of the inner channel rows 10B and 10C and the inside thereof. A rectangular covering portion 32a is integrally formed over a region slightly larger than the opening so as to cover the region. Therefore, when the wiring board 3 is bonded to the head chip 1, the portion of the covering portion 32a is disposed so as to cover the opening of the corresponding dummy channel 11b.

  According to the wiring substrate 3 shown in FIG. 5, in the channel rows 10B and 10C inside the head chip 1, the connection electrode 13b of each dummy channel 11b and the covering portion 32a of the wiring electrode 32 overlap each other, thereby Since the gap between the portion of the rows 10B and 10C and the wiring board 3 can be further reduced, the sealing around the openings of the dummy channels 11b of the inner channel rows 10B and 10C can be made more reliable. it can.

  Such a covering portion 32a is not only the inner channel rows 10B and 10C but also one end of each wiring electrode 32 corresponding to the connection electrode 13a of the dummy channel 11b of the outer channel rows 10A and 10D as shown in FIG. Can be formed similarly. That is, depending on the state of the edge of the side edge e1 of the head chip 1, there may be a case where the penetration of the adhesive is insufficient in at least one of the outer channel rows 10A or 10D. As shown in FIG. 6, a rectangular portion 32a is similarly formed at one end of each wiring electrode 32 corresponding to the connection electrode 13a of the dummy channel 11b of at least one of the outer channel rows 10A and 10D. The sealing of the dummy channel 11b in the outer channel row 10A or 10D can be ensured.

  In FIG. 6, only the portion of the wiring substrate 3 corresponding to the channel rows 10A and 10B is shown, but the same applies to one end of each wiring electrode 32 corresponding to the connection electrode 13a of the dummy channel 11b of the channel rows 10C and 10D. It is a configuration.

  In addition, after the head chip 1 and the wiring substrate 3 are joined, the wiring electrodes 32 electrically connected to the connection electrodes of the respective inner channels pass between the channels of the outer channel row. Therefore, if the connection electrode 13b surrounding the openings of the dummy channels 11b of the outer channel rows 10A and 10D is formed on the head chip 1 side, the wiring electrode 32 is obtained when the bonding accuracy between the head chip 1 and the wiring substrate 3 is poor. And the connection electrode 13b may be short-circuited if they are in contact with each other. However, the connection electrodes 13b are not formed in the outer channel rows 10A and 10D, and the corresponding wiring board 6 is formed at one end of the wiring electrode 32 as shown in FIG. 6, thereby causing a short circuit due to the effect of bonding accuracy between the head chip 1 and the wiring substrate 3. Straining such a thing will not.

  The covering portion 32a is formed at one end of the wiring electrode 32 so as to surround the region corresponding to the opening of the dummy channel 11b and also cover the inner region thereof, but as shown in FIG. In addition, the surrounding portion 32b surrounding the region corresponding to the opening of the dummy channel 11b may be formed, and the same effect can be obtained by this. The symbol a in FIG. 7 indicates a region where the metal film corresponding to the opening of the dummy channel 11b is not formed.

  In order to prevent the ink from entering the dummy channel 11b, the opening of the drive channel 11a may be sealed. Therefore, as shown in FIG. 8, at least the channel row 10B positioned inside, An encircling portion 32b surrounding the ink flow path port 31 corresponding to the drive channel 11a in a rectangular shape may be integrally formed at one end of each wiring electrode 32 corresponding to the connection electrode 13a of each drive channel 11a of 10C. .

  In FIG. 8, only the portions of the wiring board 3 corresponding to the channel rows 10A and 10B are shown, but the portions of the wiring board 3 corresponding to the channel rows 10C and 10D have the same configuration.

  Such a surrounding portion 32b is not limited to the wiring electrode 32 corresponding to the channel rows 10B and 10C located on the inner side, but also on one end of the wiring electrode 32 corresponding to at least one of the channel rows 10A and 10B located on the outer side. It can be formed similarly.

  Further, as necessary, a covering portion 32a is formed at one end of each wiring electrode 32 corresponding to the connection electrode 13b of the dummy channel 11b, and at each end of each wiring electrode 32 corresponding to the connection electrode 13a of the drive channel 11a. You may make it form the enclosure part 32b.

  Further, the means for assisting the penetration of the adhesive X (the connection electrode 13b, the covering portion 32a, and the surrounding portion 32b) may be provided on at least one of the head chip 1 side and the wiring substrate 3 side. Therefore, when means (a connection electrode 13b, a covering portion 32a, a surrounding portion 32b) for assisting the penetration of the adhesive X into both the head chip 1 and the wiring substrate 3 are provided, the head chip 1 includes a channel array. The connection electrode 13b is formed only in every other channel, and the wiring substrate 3 has a covering portion at one end of only the wiring electrode 32 corresponding to every other channel in which the connection electrode 13b is not formed in the corresponding channel row. You may make it form 32a and the surrounding part 32b.

  In FIG. 9, the connection electrode 13b surrounding the opening is formed only in the dummy channels 11b of the two channel rows 10B and 10C inside the head chip 1, and the connection electrode 13b is formed on the wiring board 3. An embodiment is shown in which a surrounding portion 32b surrounding the ink flow path port 31 corresponding to the drive channel 11a is formed at one end of the wiring electrode 32 corresponding to only the drive channel 11a in the channel rows 10B and 10C including the dummy channel 11b. FIG. 9A shows the parts of the channel rows 10B and 10C located inside the rear surface 1b of the head chip 1, and FIG. 9B shows the parts of the surface of the wiring board 3 corresponding thereto.

  On the other hand, FIG. 10 shows that the connection electrodes 13b surrounding the openings are formed only in the drive channels 11a of the two channel rows 10B and 10C inside the head chip 1, and the connection electrodes 13b are formed on the wiring board 3. An embodiment is shown in which a surrounding portion 32b surrounding a region corresponding to the opening of the dummy channel 11b is formed at one end of the wiring electrode 32 corresponding to only the dummy channel 11b in the channel rows 10B and 10C including the driven channel 11a. Yes. FIG. 10A shows the portions of the channel rows 10B and 10C located inside the rear surface 1b of the head chip 1, and FIG. 10B shows the surface of the wiring board 3 corresponding thereto. Of course, the surrounding portion 32b may be a covering portion 32a that surrounds the region corresponding to the opening of the dummy channel 11b and covers the inner region, as in FIGS.

  9 and 10, when attention is focused on one channel row, the connection electrodes 13b and the covering portions 32a or the surrounding portions 32b are alternately arranged, so that the rear surface of the head chip 1 Since the adjacent connection electrode 13b and the covering portion 32a or the surrounding portion 32b are not too close to each other on the surface 1b and the surface of the wiring board 3, the connection electrode 13b, the covering portion 32a or the surrounding portion 32b can be easily patterned.

  In addition, since the means for assisting the penetration of the adhesive X (the connection electrode 13b, the covering portion 32a, the surrounding portion 32b) may be provided on at least one of the head chip 1 side and the wiring substrate 3 side, As shown in FIGS. 5 to 8, when the wiring board 3 provided with means for assisting the penetration of the adhesive X (the covering portion 32 a and the surrounding portion 32 b) is used, the head chip 1 side is shown in FIG. 20. Similar to the head chip 400 shown in the figure, a conventional configuration in which the connection electrode 13b surrounding the opening is not provided may be used. In this case, although the penetration effect of the adhesive X is slightly inferior to the case where measures for assisting the penetration of the adhesive X are provided in both the head chip 1 and the wiring substrate 3, the edge of the side edge e1 is raised. Depending on the condition, it is possible to obtain the effect of preventing the ink from entering the dummy channel 11b simply by providing the covering portion 32a and the surrounding portion 32b only on the wiring board 3.

(Second embodiment: all channel drive type)
FIG. 11 is an exploded perspective view showing a second embodiment of the inkjet head, and FIG. 12 is a rear view of the head chip of the inkjet head shown in FIG.

  This inkjet head H2 is the same as the inkjet head H1 in that the head chip 1 includes four channel rows 10A to 10D, but all the channels 11 of each channel row 10A to 10D discharge ink. It is different in that it is an all-channel drive type head chip that is a drive channel. In the nozzle plate 2, nozzles 21 are formed so as to correspond to all the channels 11.

  In the ink jet head H2, the wiring board 3 needs to supply the ink in the manifold 4 to all the channels 11 of the head chip 1, so that ink channels are individually opened for all the channels 11. This ink flow path is smaller than the area of the opening of each channel 11 and serves as an ink squeeze hole 34 for reducing the area of the opening. In FIG. 11, 34 </ b> A to 34 </ b> D are rows of ink throttle holes 34 corresponding to the channel rows 10 </ b> A to 10 </ b> D of the head chip 1.

  Such an ink squeeze hole 34 increases the flow resistance at the inlet end of each channel 11 so that even low viscosity ink can be stably ejected. If the periphery of the ink squeeze hole 34 is not sealed with an adhesive while the wiring board 3 is bonded, ink leakage occurs and the effect of increasing the viscous resistance is reduced. There is a risk that it can no longer be achieved.

  Therefore, in the connection electrodes 13a and 13b formed on the rear surface 1b of the head chip 1, the connection electrodes 13b of the respective channels 11 of the channel rows 10B and 10C located inside are formed so as to surround the openings of the respective channels 11. The configuration is the same as in FIG. As a result, when the wiring board 3 is bonded to the rear surface 1b of the head chip 1 using an adhesive, as shown in FIG. The adhesive X penetrates so as to surround the periphery of the opening. Since the ink squeeze hole 34 has a smaller area than the opening of the channel 11, the periphery of the ink squeeze hole 34 is sealed with the adhesive X, and ink leakage can be prevented.

  In the wiring board 3, the wiring electrodes 32 corresponding to the inner channel rows 10B and 10C pass between the wiring electrodes 32 corresponding to the outer channel rows 10A and 10D, respectively, and end portions 3a and 3b. It is wired to reach up to. For this reason, among the plurality of ink throttling hole 34 rows 34A to 34D corresponding to the channel rows 10A to 10D, the inner channel is located between the adjacent ink throttling holes 34 in the outer ink throttling hole rows 34A and 34D. One wiring electrode 32 corresponding to each of the rows 10 </ b> B and 10 </ b> C passes through and extends to the end portions 3 a and 3 b of the wiring board 3. Thereby, the wiring electrode 32 can be wired with high density.

  In the inkjet head H2, the connection electrodes 13b are formed so as to surround the openings of the channels 11 of the two inner channel rows 10B and 10C among the four channel rows 10A to 10D. In the present invention, the channel row that forms the connection electrode 13b so as to surround the opening may be at least one channel row located inside of the three or more channel rows arranged side by side. The number of channel rows can be determined as appropriate according to the edge standing.

  Also in this inkjet head H2, in addition to forming the connection electrode 13b as described above on the head chip 1, the wiring board 3 is also infiltrated with the adhesive X for sealing the opening of the channel 11. Assistive measures can be taken.

  FIG. 13 is a front view of the wiring substrate 3 provided with a means for assisting the penetration of the adhesive X for sealing the opening of the channel 11 as seen from the bonding surface with the head chip 1. Since the site | part of the same code | symbol as FIG. 11 is a site | part of the same structure, detailed description is abbreviate | omitted.

  The wiring substrate 3 has a surrounding portion 32c surrounding a region corresponding to the opening of the channel 11 in a rectangular shape at one end of each wiring electrode 32 corresponding to the connection electrode 13b of each channel 11 of the inner channel rows 10B and 10C. Each is formed. Since the surrounding portion 32 c surrounds a region corresponding to the opening portion of the channel 11, it also surrounds each ink throttle hole 34.

  When this wiring board 3 is bonded to the head chip 1, the portion of the surrounding portion 32c is disposed so as to surround the opening of the corresponding channel 11, so that the channel row 10B located inside the head chip 1, In 10C, the connection electrode 13b of each channel 11 and the surrounding portion 32c of the wiring electrode 32 overlap each other, whereby the gap between the inner channel rows 10B and 10C and the wiring board 3 can be further reduced. For this reason, it is possible to more reliably seal the periphery of the ink squeeze holes 34 corresponding to the channels 11 of the inner channel rows 10B and 10C.

  Such a surrounding portion 32c includes not only the channel rows 10B and 10C positioned inside, but also the wiring electrodes 32 corresponding to the connection electrodes 13a of the channels 11 of the outer channel rows 10A and 10D as shown in FIG. It can be formed in the same manner at one end. That is, depending on how the edge of the side edge e1 rises, it may be assumed that the penetration of the adhesive is insufficient in at least one of the outer channel rows 10A or 10D. In such a case, as shown in FIG. 14, a surrounding portion 32c is similarly formed at one end of each wiring electrode 32 corresponding to the connection electrode 13a of the channel 11 of at least one of the outer channel rows 10A and 10D. Thus, sealing around the ink throttle hole 34 can be ensured also in the outer channel row 10A or 10D.

  In FIG. 14, only the portion of the wiring substrate 3 corresponding to the channel rows 10A and 10B is shown, but one end of each wiring electrode 32 corresponding to the connection electrode 13a of the channel 11 of the channel rows 10C and 10D has the same configuration. It is.

  The surrounding portion 32c is formed at one end of the wiring electrode 32 so as to surround a region corresponding to the opening portion of the channel 11 in a rectangular shape. However, as shown in FIG. A rectangular covering portion 32d may be formed so as to surround the region corresponding to the above and cover the periphery of the ink squeeze hole 34 inside. The same effect can be obtained by this. A rectangular broken line in FIG. 15 indicates a region of the opening of the channel 11.

  Moreover, the means (the connection electrode 13b, the surrounding part 32c, the coating | coated part 32d) for assisting permeation | transmission of the adhesive agent X should just be taken in at least any one of the head chip 1 side and the wiring board 3 side. Therefore, when means (a connection electrode 13b, a surrounding portion 32c, and a covering portion 32d) for assisting the penetration of the adhesive X into both the head chip 1 and the wiring substrate 3 are provided, the head chip 1 includes a channel array. The connection electrode 13b is formed only on every other channel 11, and the wiring substrate 3 is provided at one end of only the wiring electrode 32 corresponding to every other channel 11 where the connection electrode 13b is not formed in the corresponding channel row. You may make it form the surrounding part 32c or the coating | coated part 32d.

  FIG. 16 shows a connection electrode 13b that surrounds the opening only in every other channel 11 of the two channel rows 10B and 10C inside the head chip 1, and the wiring substrate 3 includes The connection electrodes 13b in the channel columns 10B and 10C including the channel 11 in which the connection electrode 13b is formed are not formed (the connection electrode 13a is formed). An embodiment is shown in which a surrounding portion 32c surrounding a region corresponding to the opening of the channel 11 is formed at one end. FIG. 16A shows the portions of the channel rows 10B and 10C located inside the rear surface 1b of the head chip 1, and FIG. 16B shows the surface of the wiring board 3 corresponding thereto.

  In the mode shown in FIG. 16, when attention is paid to one channel row, the connection electrodes 13b and the surrounding portions 32c are alternately arranged, so that each of the rear surface 1b of the head chip 1 and the surface of the wiring board 3 is provided. In FIG. 3, the adjacent connection electrodes 13b and the surrounding portions 32c are not too close to each other, and thus the patterning of the connection electrodes 13b and the surrounding portions 32c is facilitated.

  In this aspect, it goes without saying that a covering portion 32d shown in FIG. 15 may be used instead of the surrounding portion 32c.

  When the wiring substrate 3 having the mode shown in FIG. 13 to FIG. 15 is used, the head chip 1 is not provided with the connection electrode 13b surrounding the opening as in the head chip 400 shown in FIG. 20 (connection electrode 13a). Only). In this case, the penetration effect of the adhesive X is slightly inferior to the case where both the head chip 1 and the wiring substrate 3 are provided, but only on the wiring substrate 3 depending on the standing condition of the side edge e1. The effect of sealing the periphery of the ink squeeze hole 34 can be obtained simply by providing the surrounding portion 32c and the covering portion 32d.

(Wiring example of wiring electrode on wiring board)
Next, another aspect of wiring the wiring electrodes 32 on the wiring board 3 will be described.

  Each wiring electrode 32 of the wiring board 3 can be wired using both the front and back surfaces of the wiring board 3. By performing wiring using both the front and back surfaces of the wiring board 3, higher density can be achieved. FIG. 17A shows the front surface of the wiring board 3, and FIG. 17B shows the back surface of the wiring board 3. Here, the example which wired each wiring electrode 32 of the wiring board 3 shown in FIG. 5 on the front and back is shown.

  As shown in the figure, the wiring electrode 32 electrically connected to the connection electrodes 13a and 13b of the inner channel rows 10B and 10C is connected to the connection end 321 with the external wiring member 5 and the connection electrode 13b. The connection end portion 322 and the connection portion 323 that connects these connection end portions 321 and 322 are separated into three parts.

  The connection end portion 321 with the external wiring member 5 is disposed at the end portions 3 a and 3 b on the surface of the wiring substrate 3, and is a portion that becomes an electrical connection portion with the external wiring member 5.

  Further, the connection end 322 with the connection electrode 13 b is disposed on the surface of the wiring substrate 3 and is a part that directly contacts the connection electrodes 13 a and 13 b of the head chip 1. The connection end 322 is formed by an electrode portion disposed in the vicinity of the ink flow path port 31 at a portion connected to the connection electrode 13b of the drive channel 11a shown in FIG. 2, but the connection electrode 13b of the dummy channel 11b. Is formed by a part of a covering portion 32a formed so as to cover a region corresponding to the opening of the dummy channel 11b.

  Further, the connecting portion 323 is disposed on the back surface of the wiring board 3, and one end of the connecting portion 323 reaches a position corresponding to the inner end portion of the connection end portion 321, and the other end of the connection end portion 322. It is formed to reach the position. A through electrode 324 is formed at each end of the connecting portion 323 so as to penetrate the wiring board 3 from the front and back sides. The through electrode 324 electrically connects the connecting portion 323 and the connecting end portions 321 and 322. It is connected to the.

  According to the wiring board 3 on which the wiring electrodes 32 are wired in this way, each wiring electrode 32 corresponding to each connection electrode 13b of the channel rows 10B and 10C located inside when bonded to the head chip 1 is connected to the head chip. End portion of the wiring board 3 through the back side of the wiring board 3 by the connecting portion 323 without passing between the channels 11a and 11b of the adjacent channel rows 10A and 10D. 3a and 3b can be pulled out. Therefore, it is possible to reduce the occurrence of a short circuit between the adjacent wiring electrodes 32 or between the wiring electrodes 32 and the connection electrodes 13a and 13b when there is a deviation in the bonding accuracy between the head chip 1 and the wiring substrate 3. Can do.

  Thus, the wiring pattern of the wiring electrode 32 using both the front and back surfaces of the wiring board 3 can be similarly applied to wiring boards other than the embodiment of the wiring board 3 shown in FIG.

H1, H2: Inkjet head 1: Head chip 1a: Front surface 1b: Rear surface 11: Channels 10A to 10D: Channel row 11a: Drive channel 11b: Dummy channel 12: Drive wall 13, 13a, 13b: Connection electrode e1, e2: side Edge 2: Nozzle plate 21: Nozzle 3: Wiring board 31: Ink channel port 31A to 31D: Row of ink channel ports 32: Wiring electrode 321: Connection end 322: Connection end 323: Connection unit 324: Through electrode 32a: Covering part 32b: Enclosing part 32c: Enclosing part 32d: Covering part 33: Area where adhesive does not penetrate 34: Ink restricting hole 34A to 34D: Row of ink restricting holes 4: Manifold 5: External wiring member P: Plane S : Space X: Adhesive a: Area where no metal film is formed

Claims (17)

Three or more channel rows in which channels and drive walls made of piezoelectric elements are alternately arranged are arranged side by side, drive electrodes are respectively formed on the drive walls facing the channels, and openings of the channels are formed on the front and rear surfaces. And a connection electrode that is electrically connected to the drive electrode through the opening is formed on the rear surface. The channel row includes a drive channel that performs ink discharge and a dummy channel that does not discharge ink. Alternately arranged head chips,
In addition to having ink flow path openings individually corresponding to the drive channels and wiring electrodes respectively corresponding to the connection electrodes, an end portion protrudes from the side of the head chip with respect to the rear surface of the head chip. When the connection electrode and the wiring electrode are electrically connected to each other, the drive electrode is electrically drawn out to the end portion through the connection electrode and the wiring electrode, and the opening of the dummy channel An inkjet head comprising a wiring board for closing
The head chip includes the connection electrode of at least one of the dummy channel and the drive channel in at least one of the channel rows located inside the channel row arranged in parallel with three or more rows. Is formed so as to surround the opening of the channel.   The wiring board has an end portion of the wiring electrode corresponding to the dummy channel of the channel row located at least inside of the channel rows arranged in parallel in the head chip, wherein the end portion of the dummy channel 2. The ink jet head according to claim 1, wherein the ink jet head is formed so as to surround a region corresponding to the opening, or to surround and cover an inner region.   In the wiring board, an end portion of the wiring electrode corresponding to the drive channel of the channel row located at least inside of the channel rows arranged in parallel in the head chip corresponds to the drive channel. The inkjet head according to claim 1, wherein the inkjet head is formed so as to surround the ink flow path opening. Three or more channel rows in which channels and drive walls made of piezoelectric elements are alternately arranged are arranged side by side, drive electrodes are respectively formed on the drive walls facing the channels, and openings of the channels are formed on the front and rear surfaces. And a connection electrode that is electrically connected to the drive electrode through the opening is formed on the rear surface. The channel row includes a drive channel that performs ink discharge and a dummy channel that does not discharge ink. Alternately arranged head chips,
In addition to having ink flow path openings individually corresponding to the drive channels and wiring electrodes respectively corresponding to the connection electrodes, an end portion protrudes from the side of the head chip with respect to the rear surface of the head chip. When the connection electrode and the wiring electrode are electrically connected to each other, the drive electrode is electrically drawn out to the end portion through the connection electrode and the wiring electrode, and the opening of the dummy channel An inkjet head comprising a wiring board for closing
The head chip is formed such that the connection electrode of only the dummy channel in at least one of the channel rows located inside the channel row arranged in parallel with three or more rows surrounds the opening. And
In the wiring substrate, an end portion of the wiring electrode corresponding only to the driving channel in the channel row including the dummy channel formed so that the connection electrode surrounds the opening corresponds to the driving channel. An ink jet head formed so as to surround an ink flow path opening. Three or more channel rows in which channels and drive walls made of piezoelectric elements are alternately arranged are arranged side by side, drive electrodes are respectively formed on the drive walls facing the channels, and openings of the channels are formed on the front and rear surfaces. And a connection electrode that is electrically connected to the drive electrode through the opening is formed on the rear surface. The channel row includes a drive channel that performs ink discharge and a dummy channel that does not discharge ink. Alternately arranged head chips,
In addition to having ink flow path openings individually corresponding to the drive channels and wiring electrodes respectively corresponding to the connection electrodes, an end portion protrudes from the side of the head chip with respect to the rear surface of the head chip. When the connection electrode and the wiring electrode are electrically connected to each other, the drive electrode is electrically drawn out to the end portion through the connection electrode and the wiring electrode, and the opening of the dummy channel An inkjet head comprising a wiring board for closing
The head chip is formed such that the connection electrode of only the drive channel in at least one channel row located inside the channel row arranged in parallel with three or more rows surrounds the opening. And
In the wiring substrate, an end portion of the wiring electrode corresponding to only the dummy channel in the channel row including the drive channel formed so that the connection electrode surrounds the opening is formed in the opening of the dummy channel. An ink jet head characterized in that it is formed so as to surround a region corresponding to, or to surround and cover an inner region. Three or more channel rows in which channels and drive walls made of piezoelectric elements are alternately arranged are arranged side by side, drive electrodes are respectively formed on the drive walls facing the channels, and openings of the channels are formed on the front and rear surfaces. And a connection electrode that is electrically connected to the drive electrode through the opening is formed on the rear surface. The channel row includes a drive channel that performs ink discharge and a dummy channel that does not discharge ink. Alternately arranged head chips,
In addition to having ink flow path openings individually corresponding to the drive channels and wiring electrodes respectively corresponding to the connection electrodes, an end portion protrudes from the side of the head chip with respect to the rear surface of the head chip. When the connection electrode and the wiring electrode are electrically connected to each other, the drive electrode is electrically drawn out to the end portion through the connection electrode and the wiring electrode, and the opening of the dummy channel An inkjet head comprising a wiring board for closing
The wiring board has an end portion of the wiring electrode corresponding to the dummy channel of the channel row located at least inside of the channel rows arranged in parallel in the head chip, wherein the end portion of the dummy channel An inkjet head characterized by surrounding an area corresponding to an opening or surrounding and covering an inner area.   In the wiring board, an end portion of the wiring electrode corresponding to the drive channel of the channel row located at least inside of the channel rows arranged in parallel in the head chip corresponds to the drive channel. The inkjet head according to claim 6, wherein the inkjet head is formed so as to surround the ink flow path opening. Three or more channel rows in which channels and drive walls made of piezoelectric elements are alternately arranged are arranged side by side, drive electrodes are respectively formed on the drive walls facing the channels, and openings of the channels are formed on the front and rear surfaces. And a connection electrode that is electrically connected to the drive electrode through the opening is formed on the rear surface. The channel row includes a drive channel that performs ink discharge and a dummy channel that does not discharge ink. Alternately arranged head chips,
In addition to having ink flow path openings individually corresponding to the drive channels and wiring electrodes respectively corresponding to the connection electrodes, an end portion protrudes from the side of the head chip with respect to the rear surface of the head chip. When the connection electrode and the wiring electrode are electrically connected to each other, the drive electrode is electrically drawn out to the end portion through the connection electrode and the wiring electrode, and the opening of the dummy channel An inkjet head comprising a wiring board for closing
In the wiring board, an end portion of the wiring electrode corresponding to the drive channel of the channel row located at least inside of the channel rows arranged in parallel in the head chip corresponds to the drive channel. An ink-jet head formed so as to surround the ink flow path opening.   The wiring board has at least one wiring electrode between adjacent ink flow path openings in at least one of the ink flow path opening rows among the plurality of ink flow path opening rows corresponding to the channel rows. The ink jet head according to claim 1, wherein the ink jet head extends to an end portion protruding from a side of the head chip. Three or more channel rows in which channels and drive walls made of piezoelectric elements are alternately arranged are arranged side by side, drive electrodes are respectively formed on the drive walls facing the channels, and openings of the channels are formed on the front and rear surfaces. Each of which is disposed, and on the rear surface thereof, a connection electrode that is electrically connected to the drive electrode is formed through the opening, and the channel row is configured by drive channels in which all the channels discharge ink. A head chip,
In addition to the ink restriction holes for restricting the flow paths of the ink supplied to the channels individually corresponding to the channels, and wiring electrodes corresponding to the connection electrodes, respectively, an end portion with respect to the rear surface of the head chip Are connected so as to protrude from the side of the head chip, and the connection electrode and the wiring electrode are electrically connected, so that the drive electrode is connected to the end portion through the connection electrode and the wiring electrode. An ink jet head having a wiring board that is electrically drawn out,
The head chip is formed such that the connection electrode of the channel in at least one of the channel rows located inside the channel row arranged in parallel with three or more rows surrounds the opening of the channel. An ink jet head characterized by comprising:   In the wiring substrate, an end portion of the wiring electrode corresponding to the channel of the channel row located at least inside of the channel rows arranged in parallel in three or more rows in the head chip is formed in the opening of the channel. The inkjet head according to claim 10, wherein the inkjet head is formed so as to surround a region corresponding to, or to surround and surround the ink squeeze hole inside the region. Three or more channel rows in which channels and drive walls made of piezoelectric elements are alternately arranged are arranged side by side, drive electrodes are respectively formed on the drive walls facing the channels, and openings of the channels are formed on the front and rear surfaces. Each of which is disposed, and on the rear surface thereof, a connection electrode that is electrically connected to the drive electrode is formed through the opening, and the channel row is configured by drive channels in which all the channels discharge ink. A head chip,
In addition to the ink restriction holes for restricting the flow paths of the ink supplied to the channels individually corresponding to the channels, and wiring electrodes corresponding to the connection electrodes, respectively, an end portion with respect to the rear surface of the head chip Are connected so as to protrude from the side of the head chip, and the connection electrode and the wiring electrode are electrically connected, so that the drive electrode is connected to the end portion through the connection electrode and the wiring electrode. An ink jet head having a wiring board that is electrically drawn out,
In the head chip, the connection electrodes of every other channel in the at least one channel row located inside the channel row arranged in parallel with three or more rows surround the opening of the channel. And is formed as
The wiring board is formed so that the connection electrodes of every other channel in the head chip surround the opening of the channel, and the connection electrodes in the channel row surround the opening. An end portion of the wiring electrode corresponding to the non-channel is formed so as to surround the region corresponding to the opening of the channel or to cover the surrounding area of the ink squeeze hole inside the channel. An inkjet head characterized by that. Three or more channel rows in which channels and drive walls made of piezoelectric elements are alternately arranged are arranged side by side, drive electrodes are respectively formed on the drive walls facing the channels, and openings of the channels are formed on the front and rear surfaces. Each of which is disposed, and on the rear surface thereof, a connection electrode that is electrically connected to the drive electrode is formed through the opening, and the channel row is configured by drive channels in which all the channels discharge ink. A head chip,
In addition to the ink restriction holes for restricting the flow paths of the ink supplied to the channels individually corresponding to the channels, and wiring electrodes corresponding to the connection electrodes, respectively, an end portion with respect to the rear surface of the head chip Are connected so as to protrude from the side of the head chip, and the connection electrode and the wiring electrode are electrically connected, so that the drive electrode is connected to the end portion through the connection electrode and the wiring electrode. An ink jet head having a wiring board that is electrically drawn out,
In the wiring substrate, an end portion of the wiring electrode corresponding to the channel of the channel row located at least inside of the channel rows arranged in parallel in three or more rows in the head chip is formed in the opening of the channel. The inkjet head is formed so as to surround a region corresponding to, or to cover and surround the ink squeeze hole inside and surrounding the region.   The wiring board includes at least one wiring electrode between adjacent ink throttling holes in at least one ink throttling hole row among the plurality of ink throttling hole rows corresponding to the channel row. The inkjet head according to any one of claims 10 to 13, wherein the inkjet head extends to an end projecting from a side of the head chip.   The inkjet head according to claim 1, wherein the wiring substrate is formed of any one of glass, ceramics, and silicon.   The inkjet head according to claim 1, wherein a rear surface of the head chip is recessed with respect to a plane passing through two side edges along the channel row direction.   A space where the connection electrode does not exist is formed between the ends of the connection electrodes of the two outermost channel rows of the head chip and the side edges of the rear surface of the head chip, and 3 The thickness of the connection electrode of the inner channel row of the channel rows equal to or higher than the row is higher than the position of the plane passing through the two side edges along the channel row direction of the head chip from the rear surface of the head chip. The inkjet head according to claim 16, wherein the inkjet head is formed so as to be high.

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