JPS6317056A - Printing head of ink jet printer - Google Patents

Abstract

PURPOSE:To achieve the miniaturization of a printer, by possessing a vibration absorbing means absorbing the vibration from outside a printing head and the reflected wave of a vibration material in the printing head. CONSTITUTION:The damper 22a having a vibration absorbing function is pro vided in a printing head 1a following an ink supply port 21 and the damper 16b having a vibration absorbing function is provided to the ink supply part 15b of the rear end branch part of respective ink passages 111-1112. Dampers 22a, 16b are respectively composed of ink chambers 17a, 17b and the vibration absorbing membranes 18a, 18b contact the scooped out of one side thereof, composed of, for instance, rubber. The vibration due to the pressure change of ink following the shape change of a rubber tube 21b by the motion of a carrier 4 is absorbed to a damper 22a and the reflected wave due to the vibra tion of vibration materials 141-1412 is absorbed to a damper 16b. At that time, because the connection of the dampers 22a and 16b is a constricted passage 23a, they are not interfered with each other. Thereby, a subtank is not required and the title printing head can be miniaturized.

Description

Detailed Description of the Invention [Summary] A print head of an inkjet printer, which includes a first vibration absorbing means that absorbs vibrations of ink supplied from the outside, and a second vibration absorbing means that absorbs reflected waves caused by vibrations of a piezoelectric element. By providing the vibration absorbing means and connecting the first and second vibration absorbing means through a constricted flow path, it is possible to downsize the printer.

[Industrial application field]

The present invention relates to an inkjet printer used in word processors and the like, and particularly to a print head for an inkjet printer that allows the printer to be made smaller.

In recent years, office computers, word processors, and the like have become widespread due to the advancement of office automation and -IN, and noiseless and high-speed inkjet printers are often used as print output devices.

The ink used in such inkjet printers is supplied to the print head after absorbing vibrations in a sub-tank, and since the space of the sub-tank increases the size of the printer, a method of downsizing is desired.

(Prior Art) An overview of an inkjet printer is illustrated in FIG. 3, in which a carrier 4 equipped with a print head 1a and fitted and screwed onto a guide shaft 5 and a feed screw 6 is arranged in front of a platen 2. The carrier 4 is moved parallel to the platen 2 in the directions of arrows B and C by the forward and reverse rotation of a motor (not shown) connected to the feed screw 6.

The print head 1a faces the platen 2 with a predetermined gap in between, and has a large number of nozzle holes (for example, 24 in two rows) arranged in a matrix C at its tip, and selectively ejects ink onto the printing paper 3. Printing is formed by matrix dots.

' Fig. 4 shows the inside of a printing pad 1a having 24 nozzle holes in two rows, with 12 ink channels 11 in one row. ~1ltz, and a nozzle hole 71 in the nozzle part 12a.
7.2, and is formed by laminating one plate 13 by, for example, diffusion welding.

Each ink channel 11. The vibrating bodies 14 . ~14,2 is incorporated. Vibrating body 141-1
4° is composed of a piezoelectric element, both of which are connected to the control section through conductive wires (not shown). A piezoelectric element has the property of bending when a voltage is applied to it, so when a voltage is applied by a pulse signal, the vibrating body 14. ~L4+□ is the ink flow path 111
The ink is pushed out from the nozzle holes 7° to 7□ by this pressure.

At this time, the vibrating body 14. ~14I! A reflected wave is generated in the opposite direction. In order to prevent the ink pressure fluctuation caused by this vibration from affecting the other ink channels 11+ to 11,2 and affecting the ink ejection force, an ink supply section 15a at the rear of the ink channels 111 to 11,2 is provided. A damper 16a having a vibration absorbing function is provided.

As shown in FIG. 5, the damper 16a has an ink chamber 17.
and a vibration absorbing film 18 made of rubber, for example, which is in contact with the cutout on the side surface thereof.

Therefore, since there are two rows of nozzle holes, the two sets of the above configuration are placed back to back.

In addition, in FIG. 4, an external tank 1 containing ink is shown.
9. Sub tank 20. The ink supply port 21 of the print head 1a is connected to the ink supply port 21 by a rubber tube 21a, and the sub-tank 20 absorbs vibrations caused by ink pressure fluctuations caused by changes in the shape of the rubber tube 21a due to the movement of the carrier 4, and the ink is supplied from the ink supply port 21. It is supplied to the supply section 15a.

The sub-tank 20 has an ink port 20a and an ink outlet 20b at the front and rear, and is a bag-shaped tank 2 made of rubber, for example.
0c, and a cover 20e made of a synthetic resin material and having an air vent hole 20d.

Therefore, when printing, the printing pad 1a is moved in the direction of arrow A by the drive of the motor, and injects ink onto the printing paper 3 on the platen 2 to print. - When the printing for a line is completed, the printing paper 3 is moved by the specified feed amount for line feed.
is transferred in the direction of arrow C, and the print head 1a continues printing in the direction of arrow B.

[Problem that the invention seeks to solve]

According to the above conventional method, the external tank 19 and the printing pad 1
A sub-tank (for example, about 20 mm in diameter, about 1 in height)
5m5+) 20 to absorb vibrations caused by ink pressure fluctuations caused by changes in shape of the rubber tube 21a due to movement of the carrier 4 during printing. Therefore, there is a problem in that a space is required to mount the sub-tank 20, which increases the size of the printer. Additionally, parts for fixing the sub-tank 20 to the device are required.

Particularly in the case of a color inkjet printer, since different color inks are supplied to a plurality of print heads, it is necessary to have a plurality of sub-tanks, which becomes even more problematic.

[Means for solving problems]

FIG. 1 is a block diagram of the principle of the present invention.

In the figure, 1 is a print head, 12 is a nozzle part, 14 is a vibrating body, 15 is an ink supply path, and 22 is a first vibration absorber provided in the ink supply path 15 to absorb vibrations of ink supplied from the outside. means, 16 is a second vibration absorbing means provided in the ink supply path 15 and absorbs reflected waves of ink due to vibration of the vibrating body 14; 23 is a first vibration absorbing means; and a second vibration absorbing means 22.16 (a constricted flow path).

Therefore, the first vibration absorbing means 22. The second vibration absorbing means 16 absorbs vibrations and reflected waves.

[Effect]

Vibrations due to pressure fluctuations caused by changes in the shape of the supply pipe due to movement of the carrier 4 during printing are absorbed by the first vibration absorbing means 22, and reflected waves due to vibrations of the vibrating body 14 are absorbed by the second vibration absorbing means 16. Ink is ejected from the nozzle 12. At this time, the first vibration absorbing means 22. Since the connection between the vibration absorbing means 16 and the second vibration absorbing means 16 is a constricted flow path 23, they do not interfere with each other.

In this way, the first vibration absorbing means 2 is installed in the print head 1.
2. And by providing the second vibration absorbing means 16,
The device can be downsized.

〔Example〕

An embodiment of the present invention will be described with reference to FIG.

The same reference numerals refer to the same objects throughout the design.

As shown in the figure, the external tank 19 and the ink supply port 21 of the print head 16 are connected through a rubber tube 21b.

A damper 22a having a vibration absorbing function is provided within the print head 1 following the ink supply port 21.

In addition, each ink flow path 11. ~111! A damper 16b having a vibration absorbing function is provided in the ink supply section 15b at the rear end branch.
is provided. The dampers 22a and 16b have ink chambers 17a and 17b, respectively, and a vibration absorbing film 18a made of rubber, for example, in contact with a cutout on the side surface of the ink chambers 17a and 17b, similar to the damper 16a described in the conventional example shown in FIG. , 18b.

Further, the dampers 22a and 16b are connected by a constricted flow path 23a. Here dampers 21Fa, 16b,
(The constricted flow path 23a corresponds to the first and second vibration absorbing means 2f!I, 16. and the constricted flow path 23 in FIG.

With such a configuration and function, vibrations caused by pressure fluctuations in the ink due to changes in the shape of the rubber tube 21b due to movement of the carrier 4 are absorbed by the damper 22a, and vibrations caused by the vibration body 14 are absorbed by the damper 22a.
Reflected waves due to vibrations of 1 to 14 degrees are absorbed by the damper 16b. At this time, damper 228. Since the damper 16b and the damper 16b are connected through the constricted flow path 23a, they do not interfere with each other.

By providing the damper 228° and the damper 16b in the print head la in this way, the sub-tank 20 explained in the conventional example is removed, so the device can be downsized and no parts are required to install the sub-tank 20. becomes.

Furthermore, in the case of a color inkjet printer, the space of multiple sub-tanks can be reduced, resulting in a significant downsizing effect.

〔Effect of the invention〕

As described above, according to the present invention, the print head is provided with a vibration absorbing means for absorbing external vibrations and reflected waves from the vibrating body, thereby making it possible to downsize the printer.

[Brief explanation of drawings]

Fig. 1 is a block diagram of the principle of the present invention, Fig. 2 is a side view showing an embodiment of the invention, and Fig. 3 is a perspective view showing an overview of an inkjet printer. In the figures, 1 and la are print heads; 7. 7. ~7.2 is a nozzle hole, 111-111□ is an ink flow path, 12 and 12a are nozzle parts, 13 is a plate, 14.
141 to 141□ are vibrating bodies, 15.15a and 15b are ink supply parts, 16 is a second vibration absorbing means, 16a, 16b, and 22a are dampers, 17 is an ink chamber, 18.18a and 18b are vibration absorbing films, 19 20.1h is an external tank, 20.1h is a sub-tank, 21 is an ink supply port, 21a and 21b are rubber tubes, 22 is a first vibration absorbing means, and 23.23a is a constricted flow path. λr −−−−−1−−−−−'J ink! 4th tsuridaso to -n] 5th ball shadow begging θ month D mouth]

Claims (1)

[Claims] An ink supply section (15), and a nozzle section (1) branched from the ink supply section (15) at the tip.
2); a vibrating body (14) made of a piezoelectric element that is provided in each of the plurality of ink channels and vibrates when a voltage is applied; and a vibrator (14) provided in the ink supply section (15). first vibration absorbing means (22
) and a second vibration absorbing means (16) that absorbs reflected waves of the ink due to vibrations of the vibrating body (14), and a second vibration absorbing means (22) and a second vibration absorbing means (16). and a constricted flow path (23) connecting between the vibrating body and the ink having vibrations and reflected waves absorbed by the first vibration absorbing means (22) and the second vibration absorbing means (16). (14) A print head for an inkjet printer, characterized in that a voltage is selectively applied to the ink and the ink is ejected from the nozzle portion (12) to print on a print medium.