JP2012006150A - Line head and ink jet recorder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent position shift between nozzle substrates in a line head including recording heads manufactured by anode bonding of the nozzle substrates, glass substrates, and pressure chamber substrates.SOLUTION: In the line head arranged with a plurality of recording heads in a zigzag manner, the recording head has the nozzle substrate 30 formed with a plurality of nozzles 30a in an array shape, the pressure chamber substrate having a pressure chamber communicated with the nozzles 30a, and the glass substrate 32 intervening between the nozzle substrate 30 and the pressure chamber substrate. The nozzle substrate 30, the glass substrate 32, and the pressure chamber substrate are laminated in this order. The nozzle substrate 30 and the glass substrate 32 have rectangular shapes. The glass substrate 32 is wider than the nozzle substrate 30, and the four corners of the glass substrate are cut.

Description

  The present invention relates to a line head and an ink jet recording apparatus.

  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. For example, in the technique of Patent Document 1, fitting portions (7, 8) are formed on the nozzle substrate to bring the fitting portions into contact with each other to prevent this (see paragraphs 0018 to 0020, FIG. 3, etc.). .

In recent years, a nozzle substrate, a glass substrate, and a pressure chamber substrate may be firmly bonded by anodic bonding (see Patent Document 2). In this case, a technique of simply fitting nozzle substrates together as in Patent Document 1 Then, it has become impossible to cope.
That is, the nozzle substrate and the pressure chamber substrate are made of silicon (Si). Providing the fitting part (notch part) in the nozzle substrate as in Patent Document 1 is costly for cutting the silicon material. In particular, the nozzle substrate is obtained by dicing from wafer-like silicon. Cutting the chip-like silicon further wastes silicon material. In anodic bonding as in Patent Document 2, it is necessary to expose the glass substrate from the nozzle substrate or the pressure chamber substrate in order to connect the electrodes. As the method, there are a method of forming a notch in the nozzle substrate and the pressure chamber substrate, and a method of increasing the size of the glass substrate itself. In the former method, as described above, since the cost of cutting silicon constituting each substrate is high and the material is wasted, the latter method is adopted.

JP 2001-260366 A JP 2008-000941 A (refer to paragraph 0065, FIG. 8, etc.)

In this case, as shown in FIG. 7, when the recording heads 100 are arranged in a staggered manner, the glass substrate 104 exposed from the nozzle substrate 102 and the exposed portions for electrode connection come into contact with each other. When misalignment occurs between the nozzle substrates (see arrows in FIG. 7), the misalignment naturally occurs between the nozzle substrates 102.
Accordingly, a main object of the present invention is a line head manufactured by anodically bonding a nozzle substrate, a glass substrate, and a pressure chamber substrate, and the line head capable of preventing positional displacement between nozzle substrates And providing an ink jet recording apparatus including the same.

In order to solve the above problems, according to one aspect of the present invention,
In a line head in which a plurality of recording heads are arranged in a staggered pattern,
The recording head is
A nozzle substrate in which a plurality of nozzles are formed in a row;
A pressure chamber substrate having a pressure chamber communicating with the nozzle;
A glass substrate interposed between the nozzle substrate and the pressure chamber substrate;
The nozzle substrate, the glass substrate and the pressure chamber substrate are laminated in this order,
The nozzle substrate and the glass substrate have a rectangular shape,
A line head is provided in which the glass substrate is wider than the nozzle substrate, and corners at four corners thereof are cut away.

According to another aspect of the invention,
A transport roller for transporting the recording medium;
A platen that supports the recording medium;
A line head in which a plurality of recording heads are arranged in a staggered manner,
The recording head is
A nozzle substrate in which a plurality of nozzles are formed in a row;
A pressure chamber substrate having a pressure chamber communicating with the nozzle;
A glass substrate interposed between the nozzle substrate and the pressure chamber substrate;
The nozzle substrate, the glass substrate and the pressure chamber substrate are laminated in this order,
The nozzle substrate and the glass substrate have a rectangular shape,
An ink jet recording apparatus is provided in which the glass substrate is wider than the nozzle substrate, and corners at four corners thereof are cut away.

  According to the present invention, since the glass substrate is wider than the nozzle substrate and the corners of the four corners are notched, in a state where the recording heads are arranged in a staggered manner, it is a part of the nozzle substrate and the glass substrate. The portions corresponding to the notch portions can be brought into contact with each other, and displacement of the nozzle substrates can be prevented.

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. 2 is a cross-sectional view schematically showing an internal structure of a recording head. It is a top view which shows schematic structure of a nozzle substrate and a glass substrate. FIG. 4 is a plan view for schematically explaining a contact (positioning) state between recording heads. It is drawing for demonstrating the conventional problem.

  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 FIG. 3, 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 front and rear 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.
The other line heads 12, 14, 16 also have the same configuration as the line head 10.

As shown in FIG. 4, 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. As shown in FIGS. 2 and 3, the nozzle 30a extends along the X direction over a plurality of rows.

  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 an aluminum 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 aluminum substrate 38g via solder 58 exposed in the space 36a. The aluminum substrate 38g is sandwiched and protected by 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 aluminum substrate 38g, the solder 58, and the stud bump 56, the piezoelectric element 50 sandwiched between the electrodes 52 and 54 is moved to the diaphragm. The ink is deformed together with the ink 34b, and the ink in the pressure chamber 34c is pushed out and discharged from the nozzle 30a.

Here, when the nozzle substrate 30 is viewed in plan, the nozzle substrate 30 has a rectangular shape as shown in FIG. On the other hand, when the glass substrate 32 is viewed in plan, as shown in FIG. 5B, the glass substrate 32 also has a substantially rectangular shape, but the corners at the four corners are notched. Four notches 32c to 32f are formed. Convex portions 32g to 32j are formed between the notches 32c to 32f.
When the planar shapes of the nozzle substrate 30 and the glass substrate 32 are compared, the length L1 of the nozzle substrate 30 is the same as the length L2 of the glass substrate 32. The width W1 of the nozzle substrate 30 is narrower than the width W2 of the glass substrate 32, and wider than the width W3 of the convex portions 32g and 32h. In the glass substrate 32, the depth D1 of the notches 32c and 32d is deeper than the depth D2 of the notches 32e and 32f.
When the nozzle substrate 30 and the glass substrate 32 are laminated, a part of the convex portions 32 i and 32 j of the glass substrate 32 is exposed from the nozzle substrate 30 as shown in FIG.

  In a state where the recording heads 20 are arranged in a staggered pattern in the X direction, as shown in FIG. 6, in the combination 60 in which the two recording heads 20 are adjacent, the side surfaces of the nozzle substrates 30 abut on each other in the region 60a. The parallelism between them is maintained, and the convex portions 32g and the convex portions 32j of the glass substrate 32 come into contact with each other in the region 60b so that the recording heads 20 are positioned. Even in the other combination 62, the side surfaces of the nozzle substrates 30 are in contact with each other in the region 62a to maintain the parallelism between the nozzle substrates 30, and the convex portion 32g and the convex portion 32i of the glass substrate 32 are in contact with each other in the region 62b. The heads 20 are positioned with respect to each other.

  According to the present embodiment described above, the width W2 of the glass substrate 32 is wider than the width W1 of the nozzle substrate 30, and the notches 32c to 32f are formed in the glass substrate 32. Therefore, the recording head 20 is moved in the X direction. In a staggered arrangement, portions of the nozzle substrate 30 corresponding to the notches 32c to 32f of the glass substrate 32 can be brought into direct contact with each other (see regions 60a and 62a in FIG. 6). ), The positional deviation between the nozzle substrates 30 can be prevented. As a result, the overall width W0 (see FIG. 6) of the recording head 20 can be reduced more narrowly than in the conventional case where the side surfaces of the glass substrate 32 are brought into contact with each other, and the line heads 10, 12, 14,. 16, the arrangement space of the recording head 20 can be made compact.

  Furthermore, according to the present embodiment, the depths D1 and D2 are different from each other in the notches 32c and 32d on one side along the X direction of the glass substrate 32 and the notches 32e and 32f on the other side. Thus, in a state where the recording heads 20 are arranged in a staggered manner in the X direction, the glass substrates 32 are simply brought into contact with each other by the convex portions 32g and the convex portions 32i and 32j (see regions 60b and 62b in FIG. 6). The recording head 20 can be easily positioned in the X direction without completely fitting the notches 32c to 32f.

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 Aluminum 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 Combination 60a, 60b Region 62 Combination 62a, 2b region 100 recording head 102 nozzle substrate 104 glass substrate

Claims (6)

In a line head in which a plurality of recording heads are arranged in a staggered pattern,
The recording head is
A nozzle substrate in which a plurality of nozzles are formed in a row;
A pressure chamber substrate having a pressure chamber communicating with the nozzle;
A glass substrate interposed between the nozzle substrate and the pressure chamber substrate;
The nozzle substrate, the glass substrate and the pressure chamber substrate are laminated in this order,
The nozzle substrate and the glass substrate have a rectangular shape,
The line head, wherein the glass substrate is wider than the nozzle substrate, and corners at four corners thereof are cut out. The line head according to claim 1, wherein
Of the cutouts at the four corners of the glass substrate, the depth differs between the front cutout and the rear cutout along the nozzle forming direction. The line head according to claim 1 or 2,
The adjacent recording heads are characterized in that the nozzle substrates are in contact with each other in a region corresponding to a notch at a corner of the glass substrate. A transport roller for transporting the recording medium;
A platen that supports the recording medium;
A line head in which a plurality of recording heads are arranged in a staggered manner,
The recording head is
A nozzle substrate in which a plurality of nozzles are formed in a row;
A pressure chamber substrate having a pressure chamber communicating with the nozzle;
A glass substrate interposed between the nozzle substrate and the pressure chamber substrate;
The nozzle substrate, the glass substrate and the pressure chamber substrate are laminated in this order,
The nozzle substrate and the glass substrate have a rectangular shape,
An ink jet recording apparatus, wherein the glass substrate is wider than the nozzle substrate, and corners at four corners thereof are cut out. The inkjet recording apparatus according to claim 4, wherein
Of the notches at the corners of the four corners of the glass substrate, the depth differs between the front notch and the rear notch along the nozzle forming direction. The inkjet recording apparatus according to claim 4 or 5,
2. The ink jet recording apparatus according to claim 1, wherein the adjacent recording heads are in contact with each other in a region in which the nozzle substrates correspond to a notch at a corner of the glass substrate.

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