JPH10217467A - Recording head for ink jet printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simplify the connection between an electrode and a drive IC in an ink jet printer for jetting ink from a trench partitioned by a barrier wall made of a polarized piezoelectric material by applying a voltage to an electrode on the barrier wall. SOLUTION: In the recording head 4 for ink jet printer, a cover plate 55 covering a plurality of trenches 51 in a substrate 50 is composed of a wafer 57 having a drive IC and a cover member 56. A plurality of connection terminals of the wafer 57 are connected directly with a plurality of electrodes 53 formed on the opposite side faces of a plurality of barrier walls 52 by brazing.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording head for an ink-jet printer, and more particularly, to a recording head having a drive IC for outputting a drive signal to a plurality of electrodes, and electrically connecting the drive IC to the plurality of electrodes directly. Regarding connected things.

[0002]

2. Description of the Related Art Conventionally, various ink jet printers such as a bubble generation system using heat and a piezoelectric system have been put to practical use.
Among them, the recording head of the piezoelectric inkjet printer has a plurality of ink passages, a plurality of piezoelectric members constituting walls of the plurality of ink passages, and a plurality of electrodes for applying a drive voltage to the plurality of piezoelectric members, When a drive signal from a drive IC is supplied to the electrode and a drive voltage (electric field) is applied to the piezoelectric member and the piezoelectric member is deformed, the volume of the ink passage changes, and ink is ejected from the ejection nozzle at the tip of the ink passage. It has become.

The drive IC is generally provided on a connection board mounted on a carriage on which a recording head is mounted, and is connected to a printer control unit via drive control lines such as a data line, a clock line, a power supply line, and an earth line. It is electrically connected and is electrically connected to a plurality of electrodes via a plurality of output lines. The drive IC determines which ink passage should be used to eject ink from the data appearing on the data line based on the continuous clock pulse supplied from the clock line, and supplies the power supply line to the electrode of the piezoelectric member to be driven. Voltage.

For example, a conventional recording head 100 shown in FIG.
Comprises a substrate 101 made of a piezoelectric material having a plurality of grooves 102,
A cover plate 104 covering the plurality of grooves 102 to form ink passages 108 in the plurality of grooves 102, respectively;
A nozzle forming plate 105 having a plurality of nozzles 106 fixed to the distal end surface of the base plate 104; 107, and the ink introduction member 107 is fixed to a connection board 120 mounted on a carriage (not shown).

A plurality of electrodes 110 are respectively formed on the side surfaces of the plurality of partition walls 103 that partition the plurality of grooves 102 on the side of the groove 102, and a plurality of extraction electrodes 111 extending from the plurality of electrodes 110 are formed on the surface of the substrate 101. Are formed. A plurality of output lines 123 extending from the driving IC 121 are formed on the connection substrate 120, and a plurality of extraction electrodes 111 and a plurality of output lines 123 are formed.
Are connected via a flexible printed circuit board 125 (FPC) on which a plurality of output lines 126 are formed. The drive IC 121 is provided with a drive control line such as a data line, a clock line, a power supply line, and an earth line.
It is connected to a printer control unit (not shown) via the PC 122.

In the recording head disclosed in Japanese Patent Application Laid-Open No. 4-284253, a plurality of extraction electrodes extending to the side opposite to the nozzle are formed on the bottom surface of the plurality of grooves in the substrate.
In the print head of JP-A-8684, a plurality of lead electrodes are formed on a connection substrate fixed to the print head, and the plurality of lead electrodes and the plurality of electrodes are connected via a plurality of lines formed by wire bonding or the like. It is electrically connected. In Japanese Patent Application Laid-Open No. 7-304168, an IC chip is mounted on a cover plate of a recording head, and a plurality of extraction electrodes extending from the IC chip to an end opposite to the nozzle are formed. A recording head in which a plurality of electrodes and a plurality of extraction electrodes are electrically connected at a base end is described.

[0007]

A recording head 10 shown in FIG.
0, a plurality of extraction electrodes 111 extending from a plurality of electrodes 110 must be formed on the surface of the substrate 101 by sputtering or the like.
The electrical connection structure with 110 becomes very complicated. The number of output lines between the driving IC 121 and the plurality of electrodes 110 is very large, the same as that of the plurality of electrodes 110.
Since the FPC 125 is provided on the connection board 120, a very complicated structure having a very large number of output lines 126 must be applied to the FPC 125. Therefore, the electrical connection structure between the FPC 125 and the connection board 120 is very complicated. Therefore, the connection board 120
, FPC 125, and other electrodes of the recording head 100.
The structure for driving and controlling 10 becomes very complicated.

In the recording head disclosed in Japanese Patent Application Laid-Open No. 4-284253, a plurality of extraction electrodes must be formed on the bottom surfaces of the plurality of grooves.
In the recording head disclosed in Japanese Patent Application Laid-Open No. 4 (1993) -284, since a plurality of extraction electrodes must be formed on the connection substrate, an electrical connection structure between the driving IC and the plurality of electrodes is extremely complicated. JP-A-7-
Also in Japanese Patent No. 304168, since a plurality of extraction electrodes must be formed on the cover plate of the recording head, the electrical connection structure between the driving IC and the plurality of electrodes becomes very complicated as described above.

An object of the present invention is to simplify an electrical connection structure between a drive IC and a plurality of electrodes in a recording head for an ink jet printer having a plurality of electrodes for applying a drive voltage to a plurality of partitions made of a piezoelectric material. That is, the flexible printed circuit board has a simple structure, and the structure for driving and controlling a plurality of electrodes including the connection board and the printed circuit board is simplified.

[0010]

According to a first aspect of the present invention, there is provided a recording head for an ink jet printer, comprising: a substrate formed with a plurality of grooves each partitioned by a partition made of a polarized piezoelectric material; and an ink passage in the plurality of grooves. A cover plate covering a plurality of grooves of the substrate for forming each, and a plurality of electrodes for applying a drive voltage to the plurality of partitions, in a recording head for an inkjet printer, at least a portion of the substrate or the cover plate,
It is constituted by a wafer having a drive IC for outputting a drive signal to a plurality of electrodes.

A drive signal is output from the drive IC to the electrode,
When a drive voltage is applied to the partition, the partition deforms and the volume of the ink passage changes, so that the ink in the ink passage is pressurized and the ink is ejected from the inkjet nozzle. still,
When a drive voltage is applied to the partition wall, the partition wall may be configured to deform to decrease the volume of the ink passage, or may be configured to deform to increase the volume of the ink passage. Good. In the former case, the ink is ejected when the drive voltage is applied, and in the latter case, the ink is ejected when the drive voltage is released.

In this recording head for an ink-jet printer, at least a part of the substrate or the cover plate is formed of a wafer having a drive IC for outputting a drive signal to the plurality of electrodes. It becomes possible to electrically connect directly to the drive IC. Therefore, it is not necessary to form a plurality of extraction electrodes for connecting the driving IC and the plurality of electrodes respectively to the substrate or the cover plate. Further, when the drive IC of the wafer and the printer control unit are electrically connected, they can be easily connected by a drive control line such as a data line, a clock line, a power supply line, and an earth line which is smaller than the number of the plurality of electrodes. It becomes possible. Further, since the wafer of the driving IC faces the ink passage, the heat generated by the driving IC can be released via the ink, and the heat radiation effect of the driving IC can be enhanced.

According to a second aspect of the present invention, in the recording head for an ink jet printer according to the first aspect of the present invention, the wafer is provided so as to cover the plurality of grooves of the substrate at a part in the length direction of the plurality of grooves. Therefore, it becomes easy to electrically directly connect the plurality of electrodes to the drive IC of the wafer. Other operations are the same as those of the first aspect.

According to a third aspect of the present invention, there is provided a recording head for an ink jet printer according to the second aspect of the invention, wherein
C is electrically connected to a plurality of electrodes by brazing. Therefore, it is possible to electrically connect the drive IC of the wafer and the plurality of electrodes very simply and reliably. Other effects are the same as those of the second aspect.

According to a fourth aspect of the present invention, there is provided the recording head for an ink jet printer according to any one of the first to third aspects.
The drive IC for the wafer is electrically connected to a connection board mounted on a carriage via a flexible printed board. Therefore, the drive IC and the connection board can be easily and reliably connected, and the printed board is
It is possible to apply a simple configuration in which drive control lines such as a data line, a clock line, a power supply line, and an earth line, which are smaller than the number of the plurality of electrodes, are formed. In addition, the same operation as any one of the first to third aspects is achieved.

According to a fifth aspect of the present invention, there is provided a recording head for an ink jet printer according to any one of the first to fourth aspects, wherein
A nozzle forming plate having a plurality of ink jet nozzles is fixed to the substrate on the leading end side of the plurality of ink passages and the leading end surface of the cover plate. Therefore, a plurality of ink jet nozzles corresponding to a plurality of ink passages can be provided very easily, and the structure of the recording head is simplified, and the production thereof is facilitated. Is advantageous. In addition, the same operation as any one of the first to fourth aspects is achieved.

[0017]

Embodiments of the present invention will be described below with reference to the drawings. In the present embodiment, C (cyan: blue-green), M (magenta: magenta), Y (yellow:
An example in which the present invention is applied to four sets of recording heads of an ink-jet printer that records color images by ejecting four color inks of yellow (K) and black (black) on recording paper (recording medium). It is.

As shown in FIG. 1, the ink jet printer 1 basically drives a paper transport mechanism 10 including a rubber platen 11 and a carriage 21 on a main body frame 3 provided in a main body cover 2. And a recording mechanism 30 for recording a color image on the recording paper P. The holder 31 of the carriage 21 contains four color inks of C, M, Y, and K. The four sets of ink cartridges 5 to 8 are detachably mounted.

The sheet transport mechanism 10 will be described. The platen 11 is disposed in the left-right direction, and the platen shafts 11a at both left and right ends thereof are connected to the side plate 3 of the main body frame 3.
a, 3b rotatably supported, and the left platen shaft 11
The gear 12 is rotatably driven by a gear 12 attached to the left end of the a, a feed motor and a gear mechanism (not shown) attached to the side plate 3b, and the like.

The carriage driving mechanism 20 will be described.
a, the guide rod 22 supported by 3c is the platen 1
1, a guide rail 3d formed on the front end of the main body frame 3 is provided in front of the guide rod 22 in parallel with the guide rod 22 (platen 11). These guide rods 22
The carriage 21 is supported by the guide rail 3d so as to be movable in the left-right direction.

At the left end of the moving range of the carriage 21,
Driven pulley 2 rotatably supported on body frame 3
5, a stepping motor 26 and a drive pulley 27 attached to its output shaft are provided on the right end side of the moving range of the carriage 21. An endless timing belt 28 connected to the carriage 21 is stretched over these pulleys 25 and 27. When the carriage drive motor 26 is driven to rotate, the carriage 21 is driven to move in the left-right direction. ing.

The recording mechanism 30 will be described. The holder 31 of the carriage 21 has a substantially box-like shape in which four sets of ink cartridges 5 to 8 can be detachably mounted, respectively. Via the connection board 32, the recording head 40 for cyan and the recording head 4 for magenta
1. A recording head 42 for yellow and a recording head 43 for black are provided.

The recording heads 40 to 43 are shown in FIGS.
This will be described in detail with reference to FIG. However, the recording head 40
Since the recording heads 43 to 43 have the same structure, the recording head 40 for cyan will be described, and the other recording heads 41 to 43 will be denoted by the same reference numerals and will not be described.

As shown in FIGS. 2 to 7, a recording head 40 for cyan (hereinafter, referred to as a recording head) has a substrate 50 made of a piezoelectric material having a plurality of parallel grooves 51 formed in the front-rear direction.
And a cover member 5 fixed to the left side of the substrate 50 with an adhesive or the like.
6 and a wafer 57, a nozzle forming plate 58 made of a synthetic resin fixed to the rear surfaces 50a and 56a (tip surfaces) of the substrate 50 and the cover member 56, and a front surface (base end surface) of the substrate 50 and the wafer 57. ) Has an ink introduction member 75 fixed to 50b and 57b.

The wafer 57 constituting a part of the cover plate 55 is integrally formed with a driving circuit element and a wiring pattern on one side to constitute a drive IC.
/ 4, and is fixed to the front end portion of the substrate 50. A cover member 56 formed approximately 3/4 of the length of the cover plate 55 is fixed to the substrate 50 on the rear side of the wafer 57 with an epoxy adhesive or the like. Then, among the plurality of passages formed by covering the plurality of grooves 51 with the cover plate 55, every other passage not including the passages at the upper and lower ends is used as the ink passage 70, and every other passage is used. The passage is used as a partition deformation space 71 for deforming the plurality of partitions 52 that partition the plurality of grooves 51.

As shown in FIG. 6, the size of each groove 51 is, for example, width W = 0.05 to 0.5 mm and height H = 0.02 to 0.2 m.
m, length L = 10-40 mm. A plurality of ink jet nozzles 59 corresponding to the plurality of ink passages 70 are formed in the nozzle forming plate 58. As shown in FIG. 7, each of the plurality of partition walls 52 partitioning the plurality of grooves 51 has a polarization direction of arrows a and b with the center in the left-right direction as a boundary, and as shown in FIG. A pair of upper and lower electrodes 53 for applying a drive voltage to the entire partition 52 is formed on the upper and lower sides (groove side) over the entire surface by, for example, sputtering. As shown in FIG. 5, output terminals 57a connected to the wiring pattern of the drive IC are formed in a protruding manner on the side surface of the wafer 57 on the substrate 50 corresponding to the plurality of electrodes. Electrode 53
By bringing the output terminal 57a into contact with and pressurizing at a predetermined high temperature, the brazing material constituting the output terminal 57a is melted, and the two 53 and 57a are electrically connected by brazing.

The wafer 57 is made of an insulating material (for example, a ceramic material or a synthetic resin material) in order to prevent a current from flowing between the plurality of electrodes 53. Although not shown, the wafer 57 and the substrate At least the outer peripheral portion of the gap 50 is sealed with a mold resin or the like so that the ink in the ink passage 70 does not leak outside.

The ink introduction member 75 includes a manifold (not shown) formed therein and the side wall 3 of the holder 31.
1a and a cylindrical ink introduction portion 75 protruding forward.
a (see FIG. 2), when the ink cartridge 5 is mounted on the holder 31 and the leading end portion of the ink introduction portion 75a is inserted into the ink supply hole of the ink cartridge 5,
The ink in the ink cartridge 5 is supplied to the ink introduction section 75a.
Then, the ink can be supplied to the plurality of ink passages 70 via the manifold.

As shown in FIGS. 2 to 4, the driving IC of the wafer 57 and the connection substrate 32 of the holder 31 are formed of a flexible printed circuit having a data line 81, a clock line 82, a power supply line 83, an earth line, and the like. Substrate 80 (hereinafter, referred to as
The connection board 32 is connected to a printer control unit (not shown) provided on the main body frame 3 side.
Are electrically connected via an FPC 33 in which a data line, a clock line, a power supply line, an earth line (not shown) and the like are formed.

The principle of ejecting the ink in the ink passage 70 from the ink jet nozzle 59 will be described. When a drive voltage v is applied to the electrode 53 corresponding to the inkjet nozzle 59 to be ejected by a drive control signal supplied via the lines 81 to 84 by the drive IC of the wafer 75, the ink passage from the inkjet nozzle 59 The ink in 70 is ejected.

For example, as shown in FIG.
In a case where the ink 0a is ejected from the inkjet nozzle 59, two of the four electrodes 53a and 53b corresponding to the pair of upper and lower partitions 52a of the ink passage 70a are used.
By applying the driving voltage v to 3b, an electric field orthogonal to the polarization directions of arrows a and b is generated, and as shown in FIG.
The partition wall 52a is sheared in a direction orthogonal to the polarization direction. As a result, the volume of the ink passage 70a increases, and ink of the increased volume is introduced from the ink introduction member 75 into the ink passage 70a.

Next, when the application of the driving voltage v to the pair of electrodes 53b is stopped, the partition wall 52a which has been sheared returns to the initial shape as shown in FIG.
Also returns to the initial volume, and the ink in the ink passage 70 a is pressurized and ejected from the inkjet nozzle 59. In addition, from the state of FIG. 7, the pair of partition walls 52a may be configured to be sheared and deformed in the opposite direction to that of FIG. 8 to eject ink. In this case, the polarization direction of the partition walls 52a can be realized by reversing the direction of the arrows a and b, or by reversing the direction of the drive voltage v applied to the partition walls 52a.

The operation and effect of the recording head 40 will be described. Since a part of the cover plate 55 is constituted by the wafer 57 having a drive IC for outputting a drive signal to the plurality of electrodes 53, the plurality of electrodes 53 and the plurality of connection terminals of the drive IC can be very easily formed by brazing or the like. It is possible to electrically connect the drive IC and the plurality of electrodes 53 as in the related art, and it is not necessary to form a plurality of extraction electrodes for connecting the drive IC and the plurality of electrodes 53 on a substrate or a cover plate. The electrical connection structure between the drive IC of the wafer 57 and the plurality of electrodes 53 can be greatly simplified.

Further, lines 81 to 94 (data lines, clock lines, power supply lines, ground lines, etc.) which are smaller than the number of the plurality of electrodes 53 are connected to the FPC 80 for electrically connecting the drive IC of the wafer 57 and the connection substrate 32. ) Can be applied with a very simple structure. That is, the cost of the recording head 40 and the FPC 80 becomes very low, and the driving IC and the connection substrate 32 can be easily connected via the FPC 80. Therefore, in the inkjet printer 1, a structure for driving and controlling the plurality of electrodes 53 is provided. Can be simplified, and significant cost reduction can be achieved.

Further, since the wafer 57 is provided so as to cover the plurality of grooves 51 of the substrate 50 in a part of the plurality of grooves 51 in the length direction, the plurality of electrodes 53 and the driving IC of the wafer 57 are electrically connected. Direct connection is easy, and the F
This is very advantageous in providing the PC 80. Moreover,
It is possible to make the structure of the recording head 40 very compact without increasing the size.

The substrate 50 on the tip side of the plurality of ink passages 70
By fixing a nozzle forming plate 58 having a plurality of ink jet nozzles 59 to the front end surfaces 50a and 56a of the cover member 56, a plurality of ink jet nozzles 59 corresponding to the plurality of ink passages 70 can be provided very easily. In addition, since the structure of the recording head 40 is simplified and its manufacture is facilitated, the cost of the recording head 40 becomes very advantageous. Further, since the wafer 57 of the driving IC faces the ink passage 70, the heat generated by the driving IC can be released through the ink, and the heat radiation effect of the driving IC can be enhanced.

Next, a description will be given of a modified embodiment in which the recording head 40 of the above embodiment is partially modified. 1) The cover plate 55 is composed of the cover member 56 and the substrate 5
A part of 0 may be constituted by a wafer 57 having a drive IC, or a drive IC may be formed directly on the cover plate 55 or the substrate 50. 2] As shown in FIG. 9, an auxiliary electrode 53A connected to each electrode 53 is formed on at least a front side surface of each partition wall 52 on the wafer 57 side, and a driving IC of the wafer 57 and a plurality of electrodes 53 are brazed. For easy electrical connection. 3) The FPC 80 is omitted, and drive control lines (data lines, clock lines, power supply lines, ground lines, etc.) for connecting the drive IC of the wafer 57 and the connection substrate 32 are formed on the surface of the ink introduction member 75. Is also good. Since the number of the drive control lines is small, the cost required for forming the drive control lines can be reduced. Also, the connection board 32
An opening through which the ink introduction member 75 penetrates is provided, and the connection substrate 32 and the wafer 57 are brought into direct contact with each other, so that the input terminal of the drive IC is directly connected to the drive control line on the connection substrate 32 or the FPC 33 extending from the main body frame side. Can be extended to the vicinity of the wafer 57 and directly connected to a drive control line on the FPC 33.

4) A recording head may be formed by connecting the recording heads 40 of the above embodiment to the left and right, and ejecting ink from two rows of left and right inkjet nozzles arranged vertically. In this case, it is desirable to arrange a plurality of ink passages in one row between a plurality of ink passages in one row. 5] In the above-described embodiment, each partition has a structure in which the polarization directions of the arrows a and b are respectively set at the center in the left-right direction as a boundary, but the polarization in one direction (the arrow a or b in FIG. 7). It is also possible to employ a configuration or use a vertical deformation by using a laminated piezoelectric element for ejecting ink. 6] In each of the partition walls 52, a sheet-like piezoelectric material having a polarization direction opposite to that of the substrate body is bonded to a substrate body made of a piezoelectric material having most of the thickness of the substrate 50, and then a plurality of grooves 5
1 may be formed so as to have a polarization direction of arrows a and b. 7] It is also possible to use the partition deformation space 71 as an ink passage.

[0039]

According to the recording head for an ink jet printer of the present invention, at least a part of the substrate or the cover plate is constituted by a wafer having a driving IC for outputting a driving signal to a plurality of electrodes. Can be electrically connected directly by brazing or the like, a plurality of extraction electrodes for connecting the drive IC and the plurality of electrodes are omitted, and the electrical connection between the plurality of electrodes and the drive IC is eliminated. Can be simplified. Therefore, the cost of the recording head can be reduced, and the recording head can be made very compact without complicating the structure. Further, since the wafer of the driving IC faces the ink passage, the heat generated by the driving IC can be released via the ink, and the heat radiation effect of the driving IC can be enhanced.

According to the recording head for an ink jet printer of the second aspect, the same effect as that of the first aspect is obtained, but the wafer is provided so as to cover the plurality of grooves of the substrate at a part of the plurality of grooves in the length direction. Therefore, it becomes easy to electrically directly connect the plurality of electrodes to the drive IC of the wafer, and it is also advantageous in connecting the drive IC to the connection substrate.

According to the recording head for an ink jet printer of the third aspect, the same effect as that of the second aspect is obtained, but the driving IC of the wafer is electrically connected to the plurality of electrodes by brazing, so that the driving IC of the wafer is formed. And a plurality of electrodes can be electrically connected very easily and reliably.

According to the recording head for an ink jet printer of the fourth aspect, the same effect as any one of the first to third aspects is obtained, but the driving IC for the wafer is mounted on the carriage via the flexible printed circuit board. Since it is electrically connected to the mounted connection board, the drive IC and the connection board can be easily and securely connected, and as described above, the printed circuit board has very few drive control lines and is inexpensive. In addition, the electrical connection structure between the printed circuit board and the connection board can be simplified, and the structure for driving and controlling a plurality of electrodes including the connection board and the printed board can be simplified. Can be remarkably reduced in cost.

According to the recording head for an ink jet printer of the fifth aspect, the same effect as the invention of any one of the first to fourth aspects is obtained, but the substrate on the distal end side of the plurality of ink passages and the distal end of the cover plate are provided. Since a nozzle forming plate having a plurality of ink jet nozzles is fixed to the surface, a plurality of ink jet nozzles corresponding to a plurality of ink passages can be provided very easily, and the cost of the recording head can be reduced.

[Brief description of the drawings]

FIG. 1 is a perspective view of an inkjet printer according to an embodiment of the present invention.

FIG. 2 is a plan view of a main part of the ink jet printer.

FIG. 3 is a view taken in the direction of arrows III-III in FIG. 2;

FIG. 4 is a perspective view of a recording head.

FIG. 5 is a sectional view taken along line VV of FIG. 4;

FIG. 6 is an enlarged perspective view of a main part of the recording head.

FIG. 7 is a cross-sectional view of an ink passage (normal state) of the recording head.

FIG. 8 is a sectional view of an ink passage (when the volume is increased) of the recording head.

FIG. 9 is an enlarged perspective view of a main part of a recording head according to a modified embodiment.

FIG. 10 is a perspective view of a recording head according to the related art.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Ink jet printer 21 Carriage 32 Connection board 40-43 Recording head 50 Substrate 51 Groove 52, 52a Partition wall 53, 53a, 53b Electrode 55 Cover plate 57 Wafer 58 Nozzle formation plate 59 Ink jet nozzle 70, 70a Ink passage 80 Printed circuit board (FPC)

Claims (5)

[Claims] A substrate formed with a plurality of grooves each partitioned by a partition made of a polarized piezoelectric material; and a cover plate covering the plurality of grooves of the substrate for forming ink passages in the plurality of grooves, respectively. A recording head for an ink jet printer comprising: a plurality of electrodes for applying a driving voltage to a plurality of partition walls; at least a part of the substrate or the cover plate is configured by a wafer having a driving IC for outputting a driving signal to the plurality of electrodes. A recording head for an ink-jet printer, characterized in that: 2. The recording head for an ink jet printer according to claim 1, wherein the wafer is provided so as to cover the plurality of grooves of the substrate in a part of the plurality of grooves in the length direction. 3. The recording head for an ink jet printer according to claim 2, wherein the drive IC for the wafer is electrically connected to a plurality of electrodes by brazing. 4. The wafer driving IC according to claim 1, wherein the wafer driving IC is electrically connected to a connection board mounted on a carriage via a flexible printed board. The recording head for an ink jet printer according to the above. 5. A nozzle forming plate having a plurality of ink jet nozzles is fixed to a substrate on a distal end side of the plurality of ink passages and a distal end surface of a cover plate. Item 6. A recording head for an ink jet printer according to item 1.