JPH033419Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an inkjet printer, and more particularly to an inkjet printer equipped with a cleaning member for cleaning the ejection surface of an ink droplet ejection device that controls the main part.

Inkjet printers print images such as desired characters and figures by ejecting minute ink droplets from an ink droplet ejecting device onto a recording medium. Ink droplets generated when the droplets collide with the recording medium bounce back onto the ejection surface and contaminate it.

Contamination of the ejection surface of such an ink droplet ejecting device can attract fibers and dust from the recording medium, and is a contributing factor to clogging of the ink droplet ejecting holes of the ink droplet ejecting device when left unused for a long period of time. Do it. Particularly in the case of an on-demand type ink droplet ejecting device that ejects ink droplets by applying a weak pressure change to the ink near the ink droplet ejection hole, as mentioned above, the ejection of ink droplets is caused by a weak pressurizing force. Therefore, although only a few millimeters of ink is formed between the clogging and the recording medium, and there is a lot of bouncing of ink droplets, once clogging occurs, the clogging cannot be easily repaired by itself.

Therefore, to prevent ink droplets from rebounding and adhering to the ink droplet ejecting device and adhering to fibers and dust, inkjet printers have been developed which are equipped with a cleaning member for the purpose of cleaning the inkjet printer before it is left unused for a long period of time. It is disclosed in Japanese Utility Model Application No. 55-22272, Japanese Utility Model Application Publication No. 53-60827, etc.

On the other hand, it is equipped with four ink droplet ejecting devices 1y, 1m, 1c, and 1b as shown in FIG. 1, and cyan, magenta, yellow, and black inks are supplied to each ink droplet ejecting device 1y, 1m, 1c, and 1b. Color inkjet printers that print color images currently exist. In the figure, reference numeral 2 denotes a recording medium made of plain paper, coated paper, etc., on which the ink droplet ejecting devices 1y, 1m, 1c, and 1b face each other with a small gap in the print position, and 3 denotes the recording medium. A drum 4 main scans the medium 2 in the rotational direction, and a main scanning motor 4 rotates the drum 3. Reference numeral 5 denotes an arc-shaped support that supports the four ink droplet ejecting devices 1y, 1m, 1c, and 1b, and 6 supports the support 5 in the axial direction of the drum 3 via a drive wire 7 and a guide rail 8. The sub-scanning motor that causes sub-scanning rotates in the reverse direction when the printing operation is completed, and the ink droplet ejecting devices 1y, 1
Return m, 1c, and 1b to their home positions HP. 9 is an ink droplet ejecting device 1y, 1m, 1
A cleaning member made of an elastic material such as rubber is provided between the print positions c and 1b and the home position HP, and as described above, the ink droplet ejecting devices 1y, 1m, 1c and 1b are located between the print position and the home position HP. During the process of moving between the jet and the position HP, the ejection surface comes into sliding contact and removes ink droplets, dust, etc. that adhere to the jet surface and cleans it.

FIGS. 2a to 2c show the cleaning operation of the cleaning member 9 for each state of one ink droplet ejecting device 1. FIG. As shown in FIG. 2a, the cleaning member 9 has a protruding length d which protrudes into the moving area of the ink droplet ejecting device 1 so that it comes into contact with the ink droplet ejecting device 1 during its movement. As a result, as shown in FIGS. 2b and 2c, the cleaning member 9 first comes into contact with the side surface of the ink droplet ejecting device 1, and then is elastically deformed in the direction of movement and comes into contact with the ejecting surface 10. By moving the ink droplet ejecting device 1 in this state, the ejecting surface 10 is cleaned. Moreover, the larger the protrusion length d is, the better the cleaning effect is. However, the first
Four ink droplet ejecting devices 1y, 1 as shown in the figure
There are the following problems in cleaning the cleaning members m, 1c, and 1b with the common arch-shaped cleaning member 9 as shown in FIG.

That is, the cleaning operation utilizes the elastic deformation of the tip of the cleaning member 9 as described above, and the four ink droplet ejecting devices 1y, 1m, 1c,
Attempting to clean the ink droplet ejecting devices 1y, 1m, 1c, and 1b at once would place an excessive load on the sub-scanning motor 6 that drives the ink droplet ejecting devices 1y, 1m, 1c, and 1b, so this load must be reduced as much as possible. Therefore, the protruding length d of the cleaning member 9 had to be made small, making it impossible to obtain a sufficient cleaning effect. Furthermore, four ink droplet ejecting devices 1y, 1
If the cleaning member 9 and m, 1c, 1b are not positioned accurately, one ink droplet ejecting device, for example, 1y, may come into contact with the other ink droplet ejecting device 1y. 1m,
The elastic force (load) to be applied to 1c and 1b is concentrated. As a result, the relative positional relationship between one ink droplet ejecting device 1y and the other ink droplet ejecting devices 1m, 1c, and 1b may be disrupted, leading to color misregistration or the like in the printed color image.

The present invention has been devised to solve such problems, and embodiments of the present invention will be described below with reference to FIG. 4 and subsequent figures.

FIG. 4 is a side view of the cleaning member 9 of the present invention viewed from the home position HP toward the drum 3. As is clear from the figure, the cleaning member 9 of the present invention includes the ink droplet ejecting devices 1y, 1m,
Four contact parts 11y, 11m, 11c, which are divided to independently and elastically contact 1c, 1b,
11b, and the corresponding contact parts 11y, 11m, 11c, 1
an arch-shaped support portion 12 that commonly supports 1b;
It consists of and the cleaning member 9
is an integrally molded porous structure made of urethane foam or the like, and in a preferred embodiment of the present invention, the cleaning member is attached to the bases 13a and 13b of the arch-shaped holder 13 that holds the support portion 12 of the cleaning member 9. A liquid, for example water, is stored in each contact portion 11 due to capillary action.
y, 11m, 11c, and 11b are set to a wet state.

In this way, the cleaning member 9 has four independent contact parts 11y, 11m, 11c, and 11b.
b is each ink droplet ejecting device 1y, 1m, 1c, 1b
The load on the sub-scanning motor 6 is drastically reduced because it comes into contact with the sub-scanning motor 6 independently and bends elastically. That is, each contact portion 11
Slit parts 14, 14... are formed between y, 11m, 11c, 11b, and each contact part 11
This is due to the fact that when y, 11m, 11c, 11b are bent, elastic forces acting in opposite directions at each adjacent location are released to the outside due to the presence of the slit portions 14, 14, . Therefore, the contact portions 11y, 11m, 1
It becomes possible to increase the protrusion length d of 1c and 11b, and the cleaning effect can be increased. Furthermore, since the abutting portions 11y, 11m, 11c, and 11b abut independently, even if one ink droplet ejecting device 1y abuts first, only one load is applied to the ink droplet ejecting device 1y. This is due to the abutting portion 11y, and is not affected by the other three. Moreover, since the cleaning member 9 has a porous structure, it is possible to suction the deposits during cleaning, and also to wipe off the deposits in a wet state.

On the other hand, the applicant of the present application has disclosed a method for preventing clogging in an on-demand type ink droplet ejecting device 1 as shown in FIG.
112727) etc. The present invention is extremely useful for inkjet printers to which the clogging prevention method described above is applied. That is, the fifth
As shown in the figure, a first orifice 16 from which minute ink droplets 15 are ejected on demand.
, an air chamber 18 provided in front of the orifice 16 to which an air flow 17 is added from the outer periphery toward the center; In the ink droplet ejecting device 1, which is equipped with a second orifice 19 through which the droplets 15 are ejected while being surrounded by an air flow 17, the second orifice 19 is covered during non-printing operation. 1 orifice 1
The air chamber 18 is filled with ink by flowing ink from the first orifice 16, thereby preventing clogging mainly caused by drying of the ink in the first orifice 16.
Therefore, it is necessary to discharge the ink filled in the air chamber 18 prior to the printing operation, and by adding an air flow 17 from the outer periphery of the air chamber 18, the ink is transferred to the second orifice. It is discharged from 19 and discharged.

As described above, since this discharge operation is performed directly from the second orifice 19, the ink to be discharged may adhere to the vicinity of the second orifice 19, and furthermore, the particle size of the ink droplets 15 may be reduced. If high viscosity ink is used for the purpose of printing, the ink may not be ejected vigorously from the second orifice 19 and may flow out along the ejection surface 10.

Therefore, in inkjet printers to which such a clogging prevention method is applied, contamination due to ink splashes bouncing back during printing operations is more likely to occur during the discharge operation of ink as an anti-clogging liquid. The cleaning member 9 is indispensable because the dirt is more noticeable.

FIG. 6 is a perspective view of a main part of an inkjet printer of the present invention to which the clogging prevention method described above is applied. In the same figure, 20y, 20m, 20c,
20b is a lid body that covers the second injection holes 19 of the ink droplet injection devices 1y, 1m, 1c, 1b provided at the home position HP during non-printing operation, and 21 is a lid body with a cleaning member 9 disposed on one side. The ink filled in the air chamber 18 during non-printing operation is discharged into the gutter 21 by the gutter 21.

According to such a configuration, the ink droplet ejecting device 1y,1
m, 1c, 1b are home positions during non-printing operation
In HP, lid body 20y, 20m, 20c, 20
b, the air chamber 18 is in a covered state and filled with ink. Then, prior to the printing operation, the cleaning member 9 moves to face the gutter 21, and during that movement, the contact portions 11y, 11m, 1 of the cleaning member 9
The first cleaning operation is performed by slidingly contacting 1c and 11b.

When each ink droplet ejecting device 1y, 1m, 1c, 1b faces the gutter, the ink filled in the air chambers 18 is discharged from the second orifice 19. Next, ink droplet ejecting devices 1y, 1m, 1c,
1b moves again to the home position HP side, brings each ejection surface 10 into sliding contact with the cleaning member 9, and after cleaning, reverses the movement and heads toward the print position. Therefore, the ink droplet ejecting devices 1y, 1m,
In the case of 1c and 1b, since the cleaning member 9 is located closer to the home position HP than the gutter 21, it has to be moved backwards once, and in the end, the cleaning operation is performed twice after the ejection operation, so that even significant dirt can be dealt with. obtain.

As is clear from the above description, in the present invention, the cleaning member that cleans the ejection surface of each ink droplet ejecting device in the process in which a plurality of ink droplet ejecting devices move simultaneously is independent for each ink droplet ejecting device. Since it consists of a plurality of contact parts that come into elastic contact with each other and a support part that commonly supports the contact parts, it is possible to drastically reduce the load applied to the ink droplet ejecting device and its drive system. Despite this, the cleaning effect can be increased.

Furthermore, since the plurality of abutting parts are integrally molded, these abutting parts can be easily attached to predetermined positions.

Further, since the contact portions of the cleaning member are independent, even if only one ink drop ejecting device contacts such a contact portion, it will not be subjected to load from other contact portions. Furthermore, if the cleaning member has a porous structure, an even greater cleaning effect can be obtained.

[Brief explanation of drawings]

Fig. 1 is a perspective view showing a conventional example, Figs. 2 a to c are schematic diagrams showing the cleaning operation according to the state, Fig. 3 is a side view showing the main parts of the conventional example, and Fig. 4 shows the main parts of the present invention. FIG. 5 is a sectional view showing an ink droplet ejecting device suitable for the present invention, and FIG. 6 is a perspective view of essential parts showing a specific embodiment of the present invention. 1, 1y, 1m, 1c, 1b... Ink droplet ejecting device, 9... Cleaning member, 11y, 11
m, 11c, 11b... contact portion, 12... support portion.

Claims (1)

[Claims for Utility Model Registration] (1) A plurality of ink droplet ejecting devices, a support that movably supports the plurality of ink droplet ejecting devices at the same time, and a print position and a home position of the ink droplet ejecting devices. and a cleaning member that cleans the ejection surface of each ink droplet ejecting device during the process in which the ink droplet ejecting device moves therebetween, and the cleaning member is provided independently for each ink droplet ejecting device. An inkjet printer comprising a plurality of abutting parts that are integrally molded by being separated from each other by slits so as to come into elastic contact with each other, and a support part that commonly supports the abutting parts. (2) The inkjet printer according to claim 1, wherein the cleaning member has a porous structure.