JPH07323530A - Ink jet recording head unit - Google Patents

Abstract

PURPOSE:To decrease extremely noise caused by vibration of a head body by generation of strain of a piezoelectric element and its release by charging and discharging of electricity. CONSTITUTION:A flexible wiring sheet 2 is electroconductively bonded to a piezoelectric element 1a on a head body 1 wherein the piezoelectric element 1a strained by application of d.c. voltage, an ink pressurizing chamber, which is not given in the figure, pressurized by ink since a vibration part is deformed inside by the strain of the piezoelectric element, a nozzle wherein one point of the pressurized ink is jetted to recording paper in the air, and combination of those three parts are integrated in a line. Then, a damping material 5, a viscoelastic polymeric compound 6, a gelling silicone rubber 7, a soundproof material 8, and a compound 9 containing a bubble are respectively packed inside a case 3 wherein the whole is integrated into one part by securing a guide of the head body 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet recording system which, when the ink jet recording head is housed in a case and has a unit structure for mounting a recorder or a printer, suppresses vibration during ink ejection and thereby realizes low noise. Regarding the head unit.

[0002]

2. Description of the Related Art Recently, instead of a pen type recorder or a dot printer, a recorder or a printer having an ink jet type recording head unit in which a recording head does not contact a sheet has become widespread. The operating principle of this inkjet will be described with reference to FIG. The initial state diagram of (a) is a cross-sectional view of a main part showing a stable state before ink ejection. The ink 15 is an ink pressurizing chamber in which the piezoelectric element 1a is conductively bonded to the vibrating portion 14.
13, the ink replenishing section 11, the diaphragm 12, and the nozzle 1b are filled. In addition, the deformation view of the vibrating part in (b) shows that the piezoelectric element 1a receives a DC voltage from above and below due to a circuit (not shown) and a dish-shaped distortion is generated by the inverse piezoelectric effect, and the vibrating part 14 is centered around the piezoelectric element. The position is almost unchanged because it distorts a little compared to the above, and eventually, the vibrating portion 14 is deformed inside to pressurize the ink, and the fluid resistance of the aperture 12 reduces the outflow in the aperture direction to reduce the ink column from the nozzle 1b. Gives rise to 16. Furthermore,
The ink point separation diagram in (c) shows a state in which the tip of the ink column 16 becomes an ink point 17 and flies. afterwards,
When the DC voltage is set to no voltage, ink flows in from the diaphragm.
Return to the initial state diagram of (a).

Due to recent advances in electronic technology, a central processing unit is built into the equipment, and the number of recordings is increased by printing characters and mixing color inks by using multiple nozzles. The present invention also relates to this. FIG. 3 is a configuration diagram of a conventional example. In this example, the head main body 1 has a structure of the operation principle diagram of FIG. Further, an inkjet recording is made by conductively adhering the contact portions 2a of the flexible wiring board 2 to which the copper foil patterns 2b respectively conducting with the contact portions 2a are fixed and insulated. The head 10 is configured to be put in the case 3 and combined.

FIG. 4 is a cross-sectional view of a substantially central portion of the conventional example, and the head main body 1, the piezoelectric element 1a, the flexible wiring board 2, and the case 3 have already been described with reference to FIG.
The head main body 1 and the case 3 in which seven nozzles (not shown) are arranged at the bottom are positioned and fixed by the guide holes 3a, and the whole is made into one unit.

[0005]

The distortion of the piezoelectric element due to the voltage application is in the voltage application direction of the piezoelectric element, and this becomes the force for denting the movable portion as described above. According to the conventional ink jet recording head unit described with reference to FIGS. 3 and 4, voltage application and release to several piezoelectric elements occur simultaneously in a fixed cycle, and this occurs in the head main body due to generation and release of distortion of the piezoelectric elements. There is a drawback in that the head main body of the cantilever, whose vibration direction matches the strain direction of the piezoelectric element, is vibrated by applying and releasing the force of a fixed cycle and generating noise.

An object of the present invention is to provide an ink jet recording head unit that makes this noise extremely quiet.

[0007]

According to a first aspect of the present invention, there is provided a case in which an ink jet recording head is housed and a tip of the ink jet recording head is held so that a nozzle is opened outward, and an ink jet recording head is embedded in the case. And a vibration damping material to be filled in. Further, the damping material can be a viscoelastic polymer compound. Further, the viscoelastic polymer compound can be made into gel silicone rubber.

In a second aspect of the invention, there is provided a case for accommodating the ink jet recording head and holding the tip of the ink jet recording head so that the nozzle is opened outward, and the case is filled so as to fill the ink jet recording head. With a soundproof material. Further, the soundproofing material can be a compound containing bubbles.

[0009]

According to the first aspect of the invention, the vibration amplitude is attenuated by the viscoelastic polymer compound having a vibration damping function, which is filled inside the case so as to fill the ink jet recording head. Further, according to the second aspect of the invention, the noise source is wrapped by the similarly filled compound having a noise blocking function and containing bubbles.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows a cross-sectional view of the substantially central portion of an embodiment of an ink jet recording head unit according to both the first and second inventions. Since the head main body 1, the flexible wiring board 2, the piezoelectric element 1a, and the case 3 have already been described, a description thereof will be omitted. First
According to the invention, the case 3 is filled with the damping material 5 in an amount that sufficiently reduces the amplitude of the vibration of the head body 1. In this figure, the damping material is put in such a position that the head of the head body is hidden, but the head of the head body may be visible. Further, a viscoelastic polymer compound 6 and a gel silicone rubber 7 may be used instead of the vibration damping material. In the second invention, instead of the damping material 5 of the first invention, a soundproof material 8 and a compound 9 containing bubbles may be used.

[0011]

According to the present invention, a viscoelastic polymer compound having a braking function damps a head body that vibrates in a free state, and a compound containing bubbles that does not emit noise is provided. Since noise is cut off, it is possible to provide a low-noise inkjet recording head unit capable of improving quietness during recording.

[0012]

[Brief description of drawings]

[0013]

FIG. 1 is a sectional view of an embodiment according to the present invention.

[0014]

FIG. 2 is an operation principle diagram of the embodiment, (a) is an initial state diagram,
(b) is a deformation diagram of the vibrating part, and (c) is a separation diagram of ink points.

[0015]

FIG. 3 is a block diagram of a conventional example

[0016]

FIG. 4 is a sectional view of a conventional example.

[0017]

[Explanation of symbols]

 1 Head Body 1a Piezoelectric Element 2 Flexible Wiring Board 3 Case 5 Damping Material 6 Viscoelastic Polymer Compound 7 Gel Silicone Rubber 8 Soundproofing Material 9 Bubble-containing Compound

Claims (5)

[Claims] 1. An ink jet recording head, a case for accommodating the ink jet recording head and holding a tip of the ink jet recording head so that a nozzle is opened outward, and a case is filled so as to fill the ink jet recording head. An inkjet recording head unit comprising: a vibration damping material. 2. The ink jet recording head unit according to claim 1, wherein the damping material is a viscoelastic polymer compound. 3. The ink jet recording head unit according to claim 2, wherein the viscoelastic polymer compound is gel silicone rubber. 4. An ink jet recording head, a case for accommodating the ink jet recording head and holding a tip of the ink jet recording head so that a nozzle is opened to the outside, and a case is filled to fill the ink jet recording head. An ink jet recording head unit comprising: a soundproofing material. 5. The ink jet recording head unit according to claim 4, wherein the soundproof material is a compound containing bubbles.