JPH04251748A - Ink-jet head - Google Patents

Abstract

PURPOSE:To provide an ink-jet head, which can cope with the transport conditions, under which the state of a heat shock is generated, and the peeling of an interface due to the infiltration of ink from the inside of the head and further paper jamming sufficiently, gives the joining type of a nozzle plate and a channel, by which a nozzle hole is not also clogged, and has reliability. CONSTITUTION:In an ink-jet head with an ink channel structure for flying ink drips and a nozzle plate joined with the ink channel structure so as to be formed on a vertical surface in the discharge direction of the ink drips, the channel structure 2 and the nozzle plate 1 are thermally caulked and joined.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inkjet head, and more particularly to a joint structure between a nozzle plate and an ink channel structure.

0002

2. Description of the Related Art FIGS. 9 and 10 show the basic structure of a general inkjet head. 1 is a nozzle plate made of metal, resin, or the like. This nozzle plate 1 has minute nozzle holes 6 formed in a predetermined array. 2
is a channel structure made of glass, resin, etc. Reference numeral 4 denotes a flexible plate which receives the deflection of the piezoelectric element 5 and reduces the volume of the ink chamber 3. The ink supplied from the ink supply tank to the head is sent to the ink chamber 3 through the supply path 9 and through the throttle port 8 to each ink chamber. Here, pressure is applied due to the deflection of the piezoelectric element 5, and the fluid is discharged from the nozzle hole 6 via the communication path 7.

Conventionally, the bonding structure between the nozzle plate 1 and the channel structure 2 of this type of inkjet head was as shown in FIG. It was a structure. When the nozzle plate 1 and the channel structure 2 are made of different materials, such as metal and resin, this joining structure is the most commonly used structure.

0004

However, the above-described bonding structure has the disadvantage that bonding strength greater than that of the adhesive 11 cannot be obtained. First, when a heat shock condition occurs between the nozzle plate 1 and the channel structure 2 due to transportation conditions, etc., there is expansion and contraction due to the difference in thermal expansion, which causes a large shear stress between the nozzle plate 1 and the adhesive layer interface. , which can result in delamination of the adhesive interface. In this case, if only the adhesive 11 is used for bonding, the nozzle plate 1 will peel off. In addition, the adhesive layer may absorb ink and the adhesive interface may be easily peeled off. In this case as well, the nozzle plate 1 peels off as in the previous example. Furthermore, the pressure generated when paper jams during operation as a printer can be enormous. The pressure at this time cannot be prevented by adhesive strength alone, so it is necessary to take some form of pressure relief.

[0005] Furthermore, in the case of bonding using the adhesive 11, the method of applying the adhesive 11 is difficult, and there is a tendency for the adhesive to penetrate into the nozzle and become stuck, clogging the nozzle holes 6. .

The present invention was developed in view of the above-mentioned problems, and its purpose is to solve the problem of transport conditions that cause heat shock, peeling of the interface due to ink intrusion from within the head, and even paper jams. It is an object of the present invention to provide a reliable inkjet head by providing a joining form between a nozzle plate and a flow path that is sufficiently compatible and does not clog the nozzle holes.

[0007]

[Means for Solving the Problems] The present invention includes an ink channel structure for causing ink droplets to fly, and a nozzle plate joined to the ink channel structure so as to be perpendicular to the ink droplet ejection direction. In an inkjet head equipped with
The flow path structure and the nozzle plate are bonded together by thermal caulking.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of an inkjet head according to the present invention is shown in FIGS. 1 and 2. The nozzle plate 1 is made of metal such as nickel, and the channel structure 2 is made of thermoplastic resin. Peripheral protrusions 22 as shown in FIG. 3 are formed on both sides of the channel structure 2, and after the nozzle plate is superimposed on the channel structure 2 as shown in FIG. The thermally caulked state 21 is formed by heating and deforming the material and causing it to fall toward the nozzle plate side (
(See Figure 5). For heating deformation, a heating jig 50 such as a thermal iron or an ultrasonic horn can be used.

Furthermore, in order to improve the ink sealing between the nozzle plate 1 and the channel structure 2, a photosensitive resin or photosensitive rubber is applied in advance to the channel side of the nozzle plate 1, as shown in FIG. Good sealing properties can be obtained by forming the sealing material 41 excluding the nozzle portion. This sealing material 41 only needs to have sealing properties to the nozzle plate 1 and the channel structure 2, and adhesive strength is not required.

As a second embodiment, as shown in FIGS. 7 and 8, the same effect can be obtained by arranging the protrusions 31 of the channel structure in the shape of pins in the center of the nozzle plate to create a thermally caulked state. .

[0011]

[Effects of the Invention] According to the present invention, since the ink flow path structure and the nozzle plate are joined by heat caulking, a reliable joining force can be maintained even under heat shock conditions and ink infiltration into the joint. It is possible to supply a reliable head that can sufficiently cope with paper jam pressure and that does not clog the nozzle holes.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing a first embodiment of the present invention.

FIG. 2 is a partial plan view showing a first embodiment of the present invention.

FIG. 3 is a manufacturing process diagram of the first embodiment.

FIG. 4 is a manufacturing process diagram of the first embodiment.

FIG. 5 is a manufacturing process diagram of the first embodiment.

FIG. 6 is a manufacturing process diagram of the first embodiment.

FIG. 7 is a sectional view of the second embodiment.

FIG. 8 is a partial sectional view of the second embodiment.

FIG. 9 is a cross-sectional view of a general inkjet head.

FIG. 10 is a partial plan view of a common inkjet head.

FIG. 11 is a sectional view of a conventional inkjet head.

[Explanation of symbols]

1 Nozzle plate 2 Flow path structure 3 Ink flow path 4 Flexible plate 5 Piezoelectric element 6 Nozzle hole 7 Nozzle connection path 8 Aperture opening 9 Ink supply path 11 Adhesive layer 21 Peripheral heat caulking part 22 Peripheral protrusion 31 Heat caulking part 41 Seal material

Claims (1)

[Claims] 1. An inkjet head comprising an ink channel structure for ejecting ink droplets, and a nozzle plate joined to the ink channel structure so as to be perpendicular to the ink droplet ejection direction, An inkjet head characterized in that the flow path structure and the nozzle plate are joined by thermal caulking.