JP3508362B2 - Method of manufacturing inkjet head - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing an ink jet type print head which prints by ejecting ink droplets onto a print surface.

[0002]

2. Description of the Related Art Conventionally, an ink jet type print head for ejecting ink droplets onto a surface to be printed for printing, in which shear mode deformation of piezoelectric ceramics is used, a piezoelectric ceramic plate (piezoelectric substrate) is used. A plurality of grooves are cut, side walls that are the side surfaces of the grooves are polarized, electrodes are formed on the side walls, and a cover plate is bonded to the piezoelectric substrate surface using an adhesive to cover the groove openings, Further, a nozzle plate having a plurality of nozzles for ejecting ink droplets is adhered to the end faces of the piezoelectric substrate and the cover plate.

A conventional method of adhering a cover plate to a piezoelectric substrate in a print head of this type will be described below with reference to FIGS. FIG. 5 is a diagram for explaining the bonding process between the piezoelectric substrate and the cover plate, and FIG. 6 is a diagram for explaining the piezoelectric substrate and the cover plate integrated by the bonding process shown in FIG.

First, as shown in FIG. 5, a piezoelectric substrate 102 in the form of a thick plate in which a plurality of elongated strip-shaped grooves 101 are formed.
The adhesive 103 is applied to the upper side surface. This adhesive 10
A plate-shaped cover plate 104 is brought into contact with the upper side surface of the piezoelectric substrate 102 coated with 3. Next, the piezoelectric substrate 102 and the cover plate 104, which are in contact with each other via the adhesive 103 as described above, are sandwiched by the cover plate side jig 106 and the substrate side jig 107 from above and below. These two jigs 106 and 107 are tightened by bolts (not shown) fitted in a pair of holes 108 and 109 provided at both ends of the jigs 106, respectively. By this tightening, the piezoelectric substrate 102 and the cover plate 104 are arrowed. Pressurized by external force in the F direction. Next, the piezoelectric substrate 102 and the cover plate 10 sandwiched by the jig 106 and the jig 107.
4 is heated, whereby the adhesive 103 is hardened and the piezoelectric substrate 102 and the cover plate 104 are adhered to each other.

[0005]

However, in the above manufacturing method, the piezoelectric substrate 102 and the cover plate 104, which are initially flat without bending and are flat, are integrated as shown in FIG. , A direction orthogonal to the groove 101 of the inkjet head 111, that is,
In the arrangement direction of the grooves 101, the cover plate 104 has a property that the upper side face thereof is relatively expanded and the lower side face of the piezoelectric substrate 102 is relatively contracted.

The ink jet type print head has a piezoelectric substrate 1.
02 and the cover plate 104, the ink is ejected from the nozzle by utilizing the change in the ink pressure in the ink chamber due to the change in the shape and volume of the ink chamber. Cover plate 1
The deformation of 04 greatly affects the printing accuracy.

The present invention has been made to solve the above-mentioned problems and prevents deformation of the integrated cover plate and piezoelectric substrate when the cover plate and the piezoelectric substrate are bonded and integrated. It is an object of the present invention to provide a method for manufacturing the obtained inkjet head.

[0008]

In order to achieve the above object, in the method of manufacturing an ink jet head according to the invention of claim 1, a cover plate is adhered to the surface of a piezoelectric substrate on which a plurality of grooves are formed, In a method for manufacturing an inkjet head in which these are integrated, a step of applying an adhesive to the surface of the piezoelectric substrate or the surface of the cover plate in which the plurality of grooves are formed; and the step of sandwiching the adhesive
With superposed cover plate on the surface of the piezoelectric substrate, a step of sandwiching the superimposed said cover plate was and said piezoelectric base <br/> plate by the piezoelectric substrate side jig and the cover plate side tool, sandwiching the state It consists of a step of curing the adhesive at the of the piezoelectric substrate side jig
The contact surface with the piezoelectric substrate has a concave shape in the arrangement direction of the grooves formed in the piezoelectric substrate, and the contact surface of the cover plate side jig with the cover plate has a convex shape in the arrangement direction of the grooves. It is what

In the above method, since the cover plate side jig has a convex contact surface with the cover plate in the groove arrangement direction, the upper surface of the cover plate is relatively extended and a plurality of grooves are formed. A downward external force is applied to the upper surface of the integrated cover plate and the substrate, that is, the upper surface of the cover plate, in which the lower surface of the formed piezoelectric substrate tends to be deformed so as to relatively contract. Further, the piezoelectric substrate side jig pressure
Since the contact surface between the conductive substrate and concave in the direction of arrangement of the grooves, the lower of the integrated cover plate and the piezoelectric substrate, i.e. on the lower surface of the piezoelectric substrate exert an upward force. Therefore, these jigs are deformed such that the upper surface of the cover plate that may be formed on the integrated cover plate and the piezoelectric substrate relatively expands and the lower surface of the piezoelectric substrate relatively contracts. Can be prevented.

According to a second aspect of the present invention, there is provided an ink jet head manufacturing method according to the first aspect, wherein the piezoelectric substrate and the cover plate are made of ceramics.

[0011]

An ink jet head manufacturing method according to a third aspect of the present invention is the ink jet head manufacturing method according to the first or second aspect of the present invention.
The cover plate side jig and the piezoelectric substrate side jig are made of stainless steel.

In the above method, since the jig is made of stainless steel, it is less likely to be rusted, the dimensional accuracy of the jig is easily maintained, and the integrated cover plate and substrate are not deformed.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is an external view of a printer using the inkjet head of the present invention, and FIG.
FIG. 3 is a partially cutaway perspective view of an inkjet head.

In FIG. 1, the printer 1 is composed of a printing mechanism 2, a paper feeding mechanism 3, a purging device 4, and the like. The printing mechanism 2 includes an inkjet print head 5
And the ink cartridge 7 for supplying ink to the print head 5, and the head unit 6 and the ink cartridge 7 are mounted on a carriage 8. The carriage 8 is driven by a carriage motor 10 via a belt 9 and horizontally moved along a carriage shaft 11. In addition,
The print head 5 has a plurality of nozzles in a vertical line, and ejects ink from the nozzles in response to the movement of the carriage 8.

The paper feeding mechanism 3 moves the printing paper PA supplied from the paper feeding cassette or the manual paper feeding portion while facing the printing head 5, and the platen roller 1
2, a pressure roller 13, and a line feed (LF) motor (not shown). The printing paper PA supplied from a paper feed cassette or the like is held in pressure contact with the platen roller 12 and the pressure roller 13, and is moved according to the rotation of the line feed motor.

The purging device 4 eliminates the occurrence of ejection failure due to the generation of bubbles inside the print head 5 or the deposition of ink droplets on the ejection surface during the use of the print head 5, thus achieving a good ejection state. It is a device for recovery. A cap 14 is provided at the tip of the purging device 4, and when the cap 14 covers the print head 5, a negative pressure is generated by a pump to suck the defective ink inside the print head 5. The print head 5 is recovered.

In FIG. 2, a piezoelectric ceramic substrate 16 (hereinafter referred to as a piezoelectric substrate), which is a piezoelectric element of the ink jet type print head 5, is grooved in parallel with each other by dicing or the like, and a large number of grooves to be ink chambers are formed. 17 are formed. The side wall 21 (referred to as a piezoelectric side wall) forming the groove 17 is formed by a piezoelectric element polarized in the direction of arrow B, and an electric field in the direction perpendicular to this polarization direction is applied to the upper half surface of the piezoelectric side wall 21. Electrode 22
Are formed. The upper portion of the piezoelectric substrate 16 in which the groove 17 is formed is covered with a ceramic cover plate 23 having an ink supply port (not shown). A nozzle plate 19 having nozzles 18 is mounted on the end faces of the piezoelectric substrate 16 and the cover plate 23. With such a configuration, the cross-sectional shape of the groove 17 becomes a rectangle surrounded by the piezoelectric side wall 21 and the cover plate 23.

Next, the ink jet type print head 5
The printing operation will be described. Inkjet print head 5
Are mounted on the carriage 8 of the printer 1, reciprocally moved along the loaded paper PA to be printed, and the electrodes 2 based on print data (dot data) transferred from a host computer (not shown) or the like via an interface.
It operates by the voltage applied to 2. That is, the electrode 2
The piezoelectric side wall 21 is sheared and deformed by the voltage applied to the groove 2. This deformation increases the internal pressure of the groove 17, so that the ink in the groove 17 supplied from the ink cartridge is ejected from the nozzle 1.
8 is ejected and the printing operation is performed.

An embodiment of the present invention in which the piezoelectric substrate 16 and the cover plate 23 in the ink jet type print head 5 are integrated will be described with reference to FIGS. 3 and 4. FIG. 3 is a diagram for explaining a bonding process between the piezoelectric substrate 16 and the cover plate 23, and FIG. 4 is a diagram for explaining the piezoelectric substrate 16 and the cover plate 23 integrated by the bonding process shown in FIG.

First, as shown in FIG. 3, a plurality of elongated strip-shaped grooves 17 are formed on the upper side surface 16u of the thick plate-shaped piezoelectric substrate 16. The adhesive 103 is applied to the upper surface 16u of the piezoelectric substrate 16 having the plurality of grooves 17 formed therein. The upper surface 16u of the piezoelectric substrate 16 coated with the adhesive 103
The lower surface 23b of the plate-shaped cover plate 23 is brought into contact with.

Next, the piezoelectric substrate 16 and the cover plate 23, which are laminated with the adhesive 103 interposed therebetween, as described above, that is, on the upper side surface 23u of the cover plate 23 and the lower side surface 16b of the piezoelectric substrate 16, The lower side surface 24b of the cover plate side jig 24 and the upper side surface 26u of the board side jig 26 are brought into contact with each other.

In this case, the lower side surface 24b of the cover plate side jig 24 has a convex shape in the arrangement direction of the grooves 17 formed in the piezoelectric substrate 16, that is, the jig 24 is relatively thick near its central portion. , Has a downwardly convex cross-sectional shape that gradually becomes thinner toward both ends. Further, the upper surface 26u of the piezoelectric substrate side jig 26 is concave in the direction in which the grooves 17 formed in the piezoelectric substrate 16 are arranged, that is, the jig 26 is relatively thin in the vicinity of its central portion and faces both ends. It has a concave cross-sectional shape that gradually becomes thicker.

Jig 24 and jig 26 having such a shape
Between the piezoelectric substrates 16 with the adhesive 103 interposed therebetween.
The cover plate 23 is sandwiched, and further tightened by bolts (not shown) fitted into the pair of holes 108 and 109 provided at both ends of the jig 24 and the jig 26, respectively. By this tightening, the piezoelectric substrate 1
6 and the cover plate 23 are pressed by an external force in the direction of arrow F.

Subsequently, the piezoelectric substrate 16 and the cover plate 2
3 is sandwiched between jigs 24 and 26, clamped, and heated while being pressurized. Through these steps, the adhesive 103 is cured and the piezoelectric substrate 16 and the cover plate 23 are adhered to each other, whereby the upper side surface of the cover plate 23 is relatively expanded and the lower side surface of the piezoelectric substrate 16 is relatively expanded. A rectangular parallelepiped inkjet head 27 is manufactured which is prevented from being deformed so as to be contracted. This inkjet head is shown in FIG.

In the above embodiment, the lower side surface 24b of the cover plate side jig 24 is formed in a downward convex shape, and the upper side surface 26u of the piezoelectric substrate side jig 26 is formed in a concave shape.
On the other hand, the piezoelectric substrate 16 and the cover plate 23 in which the cover plate 23 is overlaid on the piezoelectric substrate 16 via the adhesive 103 and the cover plate 23 relatively extend the upper side surface of the cover plate 23, and It tends to cause deformation that causes the lower side surface to relatively shrink. here,
The piezoelectric substrate 16 and the cover plate 23 that tend to cause such deformation are placed on the upper side of the jig 24 on the cover plate side.
The deformation can be prevented by bringing the above-mentioned piezoelectric substrate side jig 26 into contact with the lower side and sandwiching it between them.

In the method of manufacturing the ink jet head of the present invention, in the method of manufacturing the ink jet head in which the cover plate 23 is bonded to the surface of the piezoelectric substrate 16 and these are integrated, the piezoelectric substrate side jig 26 is used as the piezoelectric substrate. Groove 17 whose contact surface with 16 is formed in the piezoelectric substrate 16
The concave shape in the arrangement direction of the cover plate side jig 2
4, the contact surface with the cover plate 23 is the groove 17
In addition to using the convex shape in the arrangement direction of the cover plate 23 and the piezoelectric substrate, the cover plate 23 and the piezoelectric substrate 16 having a cross-sectional shape capable of exerting an external force in the direction in which the deformation of the cover plate 23 and the piezoelectric substrate 16 integrated by adhesion are prevented Any method may be used as long as 16 is sandwiched and the adhesive is cured, and the method is not limited to the method shown in FIGS. 3 and 4. For example, in the above embodiment, the jig is tightened with a bolt, the adhesive is cured under heating, etc., but not limited to these, bonding with an adhesive that cures at room temperature, pressurization with a pressure press, etc. May be

In the above embodiment, the arrow B
The electrode 22 is provided on the upper half of the side wall 21 polarized in the direction, and the ink jet head 27 ejects the ink by the shear mode deformation of the upper half, but the side wall is formed of piezoelectric elements polarized in two different directions. However, the present invention may be used in an inkjet head that ejects ink by forming electrodes on the entire side surface of the side wall and performing shear mode deformation of the upper half and the lower half of the side wall.

[0029]

As described above, in the method of manufacturing an ink jet head according to the invention of claim 1, since the cover plate side jig has a convex surface in the groove arrangement direction, the contact surface with the cover plate is The integrated cover plate and the upper side of the piezoelectric substrate, that is, the cover, which tends to deform so that the upper side of the cover plate relatively expands and the lower side of the piezoelectric substrate having a plurality of grooves relatively contracts, that is, the cover A downward external force is applied to the upper surface of the plate. Further, the piezoelectric substrate side jig so that the concave abutment surface of the piezoelectric substrate in the direction of arrangement of the grooves, the lower of the integrated cover plate and the piezoelectric substrate, that exerts an upward force on the lower surface of the piezoelectric substrate . Therefore, these jigs can prevent deformation of the cover plate and the piezoelectric substrate, which are integrated with each other, such that the upper surface of the cover plate relatively expands and the lower surface of the piezoelectric substrate relatively contracts. . Therefore, since the integrated cover plate and piezoelectric substrate are not deformed, the accuracy of the subsequent manufacturing process of the ink jet print head is improved, and thus excellent print quality can be realized.

[0030]

[0031]

[Brief description of drawings]

FIG. 1 is an external view of a printer that employs an inkjet print head according to the present invention.

FIG. 2 is a partially cutaway perspective view of the inkjet print head according to the present invention.

FIG. 3 is a diagram illustrating a bonding process between the piezoelectric substrate and the cover plate according to the embodiment of the present invention.

FIG. 4 is a diagram illustrating a piezoelectric substrate and a cover plate that are integrated by the bonding process according to the embodiment of the present invention.

FIG. 5 is a diagram illustrating a conventional bonding process between a piezoelectric substrate and a cover plate.

FIG. 6 is a diagram illustrating a piezoelectric substrate and a cover plate integrated by a conventional bonding process.

[Explanation of symbols]

5 Inkjet print head 16 Piezoelectric substrate 17 groove 23 cover plate 24 Jig for cover plate side 26 Piezoelectric substrate side jig 27 inkjet head 103 adhesive

Claims (3)

(57) [Claims] 1. A bonding the cover plate to the plurality of grooves formed surface of the piezoelectric substrate, in the manufacturing method of the ink-jet head to integrate them, surface or the cover of the piezoelectric substrate where the plurality of grooves are formed A step of applying an adhesive on the surface of the plate; a cover plate is superposed on the surface of the piezoelectric substrate so as to sandwich the adhesive; and the cover plate and the piezoelectric substrate thus superposed are bonded to each other on a piezoelectric substrate side jig. and a step of sandwiching the cover plate side tool consists of a step of curing the adhesive at the sandwiched state, the pressure of the contact surface between the piezoelectric substrate of the piezoelectric substrate side jig
An ink jet head characterized in that the grooves formed on the electric substrate are concave in the direction in which the grooves are arranged, and the contact surface of the cover plate side jig with the cover plate is convex in the direction in which the grooves are arranged. Manufacturing method. 2. The method of manufacturing an ink jet head according to claim 1, wherein the piezoelectric substrate and the cover plate are made of ceramics. 3. The method for manufacturing an inkjet head according to claim 1, wherein the cover plate side jig and the piezoelectric substrate side jig are made of stainless steel.