JP5440411B2 - Line head module and ink jet recording apparatus - Google Patents

Description

  The present invention relates to a line head module and an ink jet recording apparatus, and more particularly to a line head module in which a plurality of recording heads are arranged in a staggered manner and an ink jet recording apparatus including the same.

  Conventionally, in image formation in an inkjet recording apparatus, there has been a strong demand for higher definition of images and higher recording speed. As a method for solving this problem, there is known a one-pass drawing method (line head method) in which recording heads are arranged in a zigzag pattern and drawing is performed only by paper feeding. The recording head is usually manufactured by sequentially laminating a nozzle substrate, a glass substrate, a pressure chamber substrate, and the like. In the line head method, the position between the recording heads (nozzle substrates) is arranged because the recording heads are arranged in a row. Deviation becomes a big problem.

Patent Documents 1 to 3 exemplify techniques for preventing misalignment between recording heads.
According to the technique of Patent Document 1, the recording head is positioned using the positioning mark of the recording head (head module 10) and the positioning mark of the jig as a reference (see paragraph 0046 and the like).
According to the technique of Patent Document 2, the concave portion of the recording head (head unit 32) is fitted to the convex portion of the base plate (long member 40) to position the recording head (see paragraphs 0065, 0066, etc.). .
According to the technique of Patent Document 3, the recording head (element substrate 1) is first pressed against the reference member and positioned in the X-axis direction, and then moved in the Y-axis direction while detecting the position and stopped at a predetermined position. Positioning in the Y-axis direction is performed (see paragraph 0017 etc.).

JP 2005-138527 A JP 2007-276163 A Japanese Patent Laid-Open No. 10-258512

However, according to the technique of Patent Document 1, positioning using a positioning mark requires a highly accurate resolution for an assembling apparatus, the apparatus itself is expensive, and positioning takes a long time. According to the technique of Patent Document 2, it is necessary to perform processing for forming a convex portion on a member (base plate) other than the recording head, which requires cost and labor. According to the technique of Patent Document 3, resolution in the Y-axis direction requires high resolution for position detection, and it can be said that there is a problem similar to that of Patent Document 1.
Accordingly, a main object of the present invention is to provide a line head module capable of easily positioning recording heads at low cost and an ink jet recording apparatus including the line head module.

In order to solve the above problems, according to one aspect of the present invention,
In a line head module in which a plurality of recording heads having a nozzle substrate on which a plurality of nozzles are formed are arranged in a staggered manner,
At least one pair of convex portions and at least one pair of concave portions corresponding to the convex portions are formed on the nozzle substrate of each recording head ,
In the adjacent recording heads, a line head module is provided in which the convex portions formed on one of the nozzle substrates are in contact with the concave portions formed on the other .

According to another aspect of the invention,
A transport roller for transporting the recording medium;
A platen that supports the recording medium;
The line head module disposed opposite to the platen;
An ink jet recording apparatus is provided.

  According to the present invention, the nozzle substrate of each recording head is formed with a corresponding convex portion and concave portion, and if these concave and convex portions are fitted, the recording heads can be positioned and inexpensive. In addition, the recording heads can be positioned easily.

1 is a perspective view illustrating a schematic configuration of an ink jet recording apparatus. FIG. 4 is a plan view for schematically explaining an arrangement state of recording heads. FIG. 2 is a perspective view schematically showing an appearance of a recording head. FIG. 4 is a perspective view of the appearance of the recording head as viewed from a different angle from that of FIG. 3. FIG. 2 is a cross-sectional view schematically showing an internal structure of a recording head. FIG. 4 is a plan view for schematically explaining a contact (positioning) state between recording heads. It is a top view which shows the modification of FIG.

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

As shown in FIG. 1, the inkjet recording apparatus 2 includes a platen 6 that supports a recording medium 4. A transport roller 8 for transporting the recording medium 4 is provided before and after the platen 6. When the conveyance roller 8 is driven, the recording medium 4 is conveyed from the rear to the front while being supported by the platen 6.
In the following, the conveyance direction of the recording medium 4 is referred to as “Y direction”, and the direction orthogonal to the conveyance direction is referred to as “X direction”. The Y direction and the X direction are directions on the horizontal plane.

  Above the platen 6, line heads 10, 12, 14, and 16 are provided from the upstream side to the downstream side in the Y direction. Each of the line heads 10, 12, 14, 16 extends in the X direction, and discharges ink of each process color of Y, M, C, K toward the recording medium 4.

When the line head 10 is viewed from below, the five recording heads 20 are arranged in a zigzag pattern along the X direction as shown in FIG.
As shown in FIGS. 3 and 4, the recording head 20 has a rectangular parallelepiped casing 22 in appearance, and a nozzle substrate 30 is provided on the casing 22. A flange 24 is integrally formed on the left and right sides of the housing 22. As shown in an enlarged portion (cross section) in FIG. 2, a recess 24 a is formed in the flange 24, and the flange 24 is fixed to a support body 28 which is a part of the line head 10 by a screw 26. The head of the screw 26 is buried in the recess 24a.
Each of the line heads 10, 12, 14, and 16 is an example of a line head module, and the line heads 12, 14, and 16 have the same configuration as the line head 10.

As shown in FIG. 5, the recording head 20 roughly includes six members, a nozzle substrate 30, a glass substrate 32, a pressure chamber layer 34, a first adhesive layer 36, a wiring layer 38, and a second adhesive layer 40, stacked in the vertical direction. An ink tank 42 is provided thereon.
In the following, the stacking direction of these members is referred to as the “Z direction”. The Z direction is orthogonal to the X direction and the Y direction.

  The nozzle substrate 30 is a silicon substrate and is located in the lowermost layer. A plurality of nozzles 30 a are formed on the nozzle substrate 30. The nozzles 30a are formed by dry etching and extend in the X direction over a plurality of rows as shown in FIGS.

  The glass substrate 32 is a glass substrate, and is laminated on the upper surface of the nozzle substrate 30 and anodic bonded to the nozzle substrate 30 as shown in FIG. In the glass substrate 32, a through hole 32a communicating with the nozzle 30a of the nozzle substrate 30 is formed in the Z direction.

The pressure chamber layer 34 includes a pressure chamber substrate 34a and a diaphragm 34b.
The pressure chamber substrate 34 a is a silicon substrate, is laminated on the upper surface of the glass substrate 32, and is anodic bonded to the glass substrate 32.
The pressure chamber substrate 34a is formed with a pressure chamber 34c that applies a discharge pressure to the ink discharged from the nozzle 30a. The pressure chamber 34c is formed so as to penetrate the pressure chamber substrate 34a in the Z direction. The pressure chamber 34c is provided above the through hole 32a and the nozzle 30a, and communicates with the through hole 32a and the nozzle 30a.
The diaphragm 34b is laminated and bonded to the upper surface of the pressure chamber substrate 34a so as to cover the opening of the pressure chamber 34c. That is, the diaphragm 34b constitutes the upper wall portion of the pressure chamber 34c. An oxide film is formed on the surface of the diaphragm 34b.
A flow path 34d formed of a through hole is formed in the pressure chamber substrate 34a and the diaphragm 34b. The pressure chamber 34 c and the flow path 34 d communicate with each other via a communication path 32 b formed in the glass substrate 32.

The first adhesive layer 36 is laminated on the upper surface of the diaphragm 34b. The first adhesive layer 36 is a photosensitive resin layer that bonds the vibration plate 34b and the wiring layer 38, and is a partition layer that forms a space 36a therein. The space 36a is formed above the pressure chamber 34c so as to penetrate the first adhesive layer 36 in the Z direction, and accommodates the piezoelectric element 50 therein.
The piezoelectric element 50 is formed in substantially the same plan view shape as the pressure chamber 34c, and is provided at a position facing the pressure chamber 34c with the diaphragm 34b interposed therebetween. The piezoelectric element 50 is an actuator made of PZT (lead zirconium titanate) for deforming the diaphragm 34b. Two electrodes 52 and 54 are provided on the upper and lower surfaces of the piezoelectric element 42, and the lower electrode 54 is connected to the diaphragm 34b.
The first adhesive layer 36 is formed with a flow path 36b composed of a through hole. The channel 36b communicates with the channel 32b.

The wiring layer 38 includes an interposer 38a which is a silicon substrate.
The lower surface of the interposer 38a is covered with two layers of silicon oxide insulating layers 38b and 38c, and the upper surface is also covered with an insulating layer 38d of silicon oxide. Of the insulating layers 38b and 38c, an insulating layer 38c positioned below is laminated on the upper surface of the first adhesive layer 36 and bonded thereto.
A through hole 38e is formed in the Z direction in the interposer 38a, and a through electrode 38f is inserted through the through hole 38e. One end of a conductive substrate 38g extending in the horizontal direction is connected to the lower end of the through electrode 38f. A stud bump 56 provided on the electrode 52 on the upper surface of the piezoelectric element 50 is connected to the other end of the conductive substrate 38g via a solder 58 exposed in the space 36a. The conductive substrate 38g is made of aluminum or copper, and is protected by being sandwiched between two insulating layers 38b and 38c on the lower surface of the interposer 38a. A copper substrate 38h is connected to the upper end of the through electrode 38f. The copper substrate 38h extends in the horizontal direction.
The interposer 38a and the insulating layers 38b, 38c, and 38d are formed with a flow path 38i formed of a through hole. The flow path 38i is formed so as to penetrate the interposer 38a in the Z direction. The channel 38i communicates with the channel 36b.

The second adhesive layer 40 is laminated and bonded to the upper surface of the insulating layer 38d of the interposer 38a while covering the copper substrate 38h disposed on the upper surface of the wiring layer 38.
The second adhesive layer 40 is a photosensitive resin layer that adheres the ink tank 42 and a protective layer that protects the copper substrate 38h.
In the second adhesive layer 40, a flow path 40a formed of a through hole is formed in the Z direction. The channel 40 a communicates with the channel 38 i of the wiring layer 38.

  In the recording head 20 having the above configuration, the ink in the ink tank 42 is supplied to the pressure chamber 34c through the flow paths 40a, 38i, 36b, and 34d and the communication path 32b. In this state, when a voltage is applied between the electrodes 52 and 54 through the copper substrate 38h, the through electrode 38f, the conductive substrate 38g, the solder 58, and the stud bump 56, the piezoelectric element 50 sandwiched between the electrodes 52 and 54 vibrates. The ink is deformed together with the plate 34b, and the ink in the pressure chamber 34c is pushed out and discharged from the nozzle 30a.

Here, when each recording head 20 is viewed in plan, as shown in FIGS. 2 and 6, a pair of convex portions 60 is formed on one side of the nozzle substrate 30, and 1 on the other side. A pair of recesses 62 is formed.
In particular, as shown in FIG. 6, the convex portion 60 protrudes in a trapezoidal shape, and the two corner portions 60 a and 60 b are bent. The convex portion 60 is tapered (tapered) toward the outside. On the other hand, the concave portion 62 is also cut out in a trapezoidal shape and corresponds to the shape of the convex portion 60. The convex portion 60 and the concave portion 62 are fitted to each other, and are in line contact with each other in a state where the convex portion 60 and the concave portion 62 are viewed in plan. Similar to the nozzle 30a, the convex portion 60 and the concave portion 62 are formed by dry etching.

  When the recording heads 20 are fixed to the support 28 and the recording heads 20 are arranged in a staggered manner, first, a certain recording head 20 is fixed to the support 28 with screws 26. Thereafter, another recording head 20 is moved in the X direction with respect to the convex portion 60 or concave portion 62 of the glass substrate 30 of the recording head 20 already fixed, and the concave portion 62 or convex portion 60 of the glass substrate 30 is fitted. At that position, the recording head 20 is fixed to the support 28 with screws 26. By repeating such an operation, the recording heads 20 are arranged in a staggered manner.

  According to the present embodiment described above, since the nozzle substrate 30 is made of silicon and is dry-etched, the highly accurate convex portions 60 and concave portions 62 are formed at low cost. When the recording heads 20 are arranged in a staggered manner, the other recording head 20 is moved in one direction with respect to the already fixed recording heads 20 and the convex portions 60 and the concave portions 62 are simply fitted. . In this case, since the convex portion 60 is formed in a taper shape, even if the positions of the convex portion 60 and the concave portion 62 are slightly shifted, one slides smoothly on the other and contacts. Therefore, the recording heads 20 can be easily positioned at low cost, and as a result, the recording heads 20 are positioned using the contact between the nozzle substrates 30, so that highly accurate positioning can be realized. .

In addition, as shown in FIG. 7, the shape of the convex part 60 of the glass substrate 30 is substantially trapezoidal, and one corner 60a may be bent and the other corner 60c may be curved. In this case, in a state where the convex portion 60 and the concave portion 62 are viewed in plan, the corner portion 60a and the concave portion 62 are in line contact, and the corner portion 60c and the concave portion 62 are in point contact.
The shape of the convex part 60 and the recessed part 62 of the glass substrate 30 shown in FIG. 6, FIG. 7 is an example.
The shape of the convex portion 60 and the concave portion 62 may be a polygonal shape such as a triangular shape or a rectangular shape, may be a semicircular shape or an elliptical shape, and can be appropriately changed as long as they can be fitted to each other. It is. Two or more pairs of convex portions 60 and concave portions 62 may be provided, or one or two or more convex portions 60 and concave portions 62 may be formed on the glass substrate 30 without forming a pair.

DESCRIPTION OF SYMBOLS 2 Inkjet recording device 4 Recording medium 6 Platen 8 Conveyance roller 10, 12, 14, 16 Line head 20 Recording head 22 Case 24 Flange 26 Screw 28 Support body 30 Nozzle substrate 30a Nozzle 32 Glass substrate 32a Through-hole 32b Communication path 32c- 32f Notch 32g-32j Protruding part 34 Pressure chamber layer 34a Pressure chamber substrate 34b Diaphragm 34c Pressure chamber 34d Channel 36 First adhesive layer 36a Space 36b Channel 38 Wiring layer 38a Interposers 38b, 38c, 38d Insulating layer 38e Through Hole 38f Through-electrode 38g Conductive substrate 38h Copper substrate 38i Channel 40 Second adhesive layer 40a Channel 42 Ink tank 50 Piezoelectric element 52, 54 Electrode 56 Stud bump 58 Solder 60 Convex 60a, 60b, 60c Corner 62 Concave

Claims (6)

In a line head module in which a plurality of recording heads having a nozzle substrate on which a plurality of nozzles are formed are arranged in a staggered manner,
At least one pair of convex portions and at least one pair of concave portions corresponding to the convex portions are formed on the nozzle substrate of each recording head ,
In the adjacent recording heads, the convex portion formed on one side of the nozzle substrates and the concave portion formed on the other are in contact with each other . The line head module according to claim 1,
The convex portion has a trapezoidal shape;
A line head module, wherein both corners of the convex part are bent. The line head module according to claim 1,
The convex portion has a substantially trapezoidal shape;
A line head module, wherein one corner of the convex portion is bent and the other corner is curved. In the line head module according to any one of claims 1 to 3,
The line head module, wherein the recess has a trapezoidal shape. In the line head module according to any one of claims 1 to 4,
The nozzle substrate is made of silicon;
The line head module, wherein the convex portion and the concave portion of the nozzle substrate are formed by dry etching. In an inkjet recording device provided with the line head module as described in any one of Claims 1-5,
A transport roller for transporting the recording medium;
A platen that supports the recording medium;
The line head module disposed opposite to the platen;
An ink jet recording apparatus comprising:

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