JPH02102066A - Ink jet recorder - Google Patents

Abstract

PURPOSE:To effectively utilize ink and to accurately humidify by covering the nozzle of an ink jet head with capping means, and providing dry-preventing means for discharging ink particles when the capping means is separated from the nozzle. CONSTITUTION:The power source of a recorder is turned ON, and whether an ink jet head 2 is disposed at a cap position or not is verified. If not, the head 2 is moved to the cap position, and is capped, ink particles are discharged from all the nozzles from the head 2 toward a space 13, absorbed to an ink absorber 14 mounted in the space 13, and the ink in which its viscosity is raised at the end of the nozzle generated during the leaving period up to the energization of the power source is simultaneously discharged. When a record signal is applied, capping means 10 is separated from the head, a pump is started, and recording is started at the head.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an inkjet recording device, and particularly to an inkjet recording device that prevents the inkjet head from drying and eliminates ejection holes caused by drying.

[Conventional technology]

A capping means with an ink absorber provided inside is seen in Japanese Patent Laid-Open No. 56-60256, and when a problem such as poor ejection occurs, a suction pump is operated to suck ink from the nozzle to recover from the problem. At the same time, the ink absorber inside the cap is wetted with ink.

[Problem to be solved by the invention]

However, in the conventional technology described above, the ink absorber does not get wet with ink unless a trouble occurs, and therefore a reliable moisturizing effect cannot be obtained. Also, if you run the suction pump periodically just to moisturize, for example, a large amount of ink will be consumed, and if there is a large amount of ink in the cap, it will drip when you remove the cap. It fell down and caused dirt.

SUMMARY OF THE INVENTION An object of the present invention is to provide an inkjet recording apparatus with a simple configuration that eliminates the above-mentioned problems and at the same time eliminates ejection hole clogging caused by ink drying in a nozzle portion.

[Means for Solving the Problems] The inkjet recording apparatus of the present invention includes: (1) a capping means for covering a nozzle portion of an inkjet head having a space inside provided near a recording range and outside the recording range; , an ink absorber installed in the space, a suction means for sucking ink in the space to optimize the amount of ink in the space when the space of the capping means is open to the atmosphere; drying prevention means for discharging ink droplets toward the space, (2) comprising the drying prevention means for discharging ink droplets toward the space when the power of the recording device is turned on, and (3) when the power is turned on. , the drying prevention means stops ejecting the ink droplets when the nozzle portion of the inkjet head is covered with the capping means, and ejects the ink droplets when the capping means leaves the nozzle portion of the inkjet head; (4) When the power is turned on, the ejection of the ink droplets is stopped while the nozzle portion of the inkjet head is covered with the capping means, and when the capping means is separated from the nozzle portion of the inkjet head. The apparatus is characterized by comprising the drying prevention means for ejecting the ink droplets almost regularly.

〔Example〕

FIG. 1 is an embodiment showing the main structure of an inkjet recording apparatus according to the present invention. A carriage 3 carrying an inkjet head 2 is guided and supported by a guide shaft 4, and the driving force of a motor 5 is transmitted to the carriage 3 via a timing belt 6, so that the carriage 3 moves along a platen 7. The position of the carriage 3 is detected by a home position sensor 9, which is a light emitting/receiving element installed at the left end portion, and is controlled based on a magnetic or optical encoder signal with the home position as a reference. The recording signal is supplied to the inkjet head 2 via the flexible wiring 8.

The capping means 10 installed on the left side of the recording range includes a rubber cap 11 and a holding frame 12 for holding the cap.
An ink absorber 14 is installed in the space 13.

Reference numeral 21 denotes a pump as a suction means, which is capable of suctioning ink from the inkjet head 2 by applying negative pressure to the space 13 with the tip of the inkjet head 2 covered with the cap 11, and at the same time when the cap 11 is opened. In this state, the ink in the space 13 is sucked to prevent excess ink from dripping, and the amount of ink contained in the ink absorber 14 is always adjusted to a constant amount determined by the ink holding power of the ink absorber. It was designed to do so.

22 is a processing tank for processing ink overflowing from the pump 21.

FIG. 2 shows an embodiment of the capping means according to the invention. FIG. 2 is a view seen from above, and when the carriage 3 moves to the left, the engaging portion 20 of the carriage 3 retracts the capping means 10 from the inkjet head 2, and when the carriage 3 further moves to the left, This time, the capping means 10 moves in the direction of the inkjet head 2,
When the cap 11 covers the nozzle portion 16 of the inkjet head 2 according to the carriage position detection means, the carriage 3 stops. The spring 15 is a cap spring that urges the cap 11 to airtightly cover the nozzle portion 16 of the inkjet head 2.

When the carriage 3 moves from the capping state to the right toward the recording range, the operation opposite to the above is performed.

FIG. 3 shows another embodiment for moving the capping means 10 relative to the inkjet head 2, in which the DC solenoid 1
9 is provided and the capping means 10 is moved by controlling energization.

When using black ink as recording ink, cap 11
and the ink absorber 14 is black. In an inkjet recording device, printing is inspected during manufacture and assembly, and as will be described later, ink droplets are ejected toward the space 13 during use. By selecting the cap 11 and cap 11, the ink stains that occur during inspection when new are not noticeable, and even after the product has been used, it can be used for a long time without conspicuous stains caused by the jetting of ink particles. .

FIGS. 4 and 5 show other embodiments of the capping means according to the present invention, which are sectional views taken in the direction of arrow 17 in FIG. A rubber cap 11 is fixed to a holding frame 12 made of a plastic molded product, and the cap 1
An ink absorber 14 is attached within the first space 13 . In FIG. 4, the ink absorber 14 is arranged in a plane so as to face the nozzle of the inkjet head within the space 13 of the cap 11, and in FIG.
It was installed at the bottom of 3.

FIG. 6 and FIG. 7 are examples of operational flowcharts of the inkjet recording apparatus according to the present invention.

As can be seen from FIG. 6, when the power of the recording apparatus is turned on, it is first verified whether or not the inkjet head 2 is in the cap position, and if not, the head 2 moves to the cap position and is capped. Several tens to hundreds of pulses of ink droplets are ejected from all nozzles from the inkjet head 2 toward the above-mentioned space 13, and the ink is absorbed by the ink absorber 14 installed in the space 13, and at the same time, the power is turned on. The ink whose viscosity has increased at the tip of the nozzle during the period when the nozzle is left unused is discharged to prepare for ink ejection without any ejection holes within the recording range. Note that when the power is turned on, the nozzle part of the inkjet head is usually covered with a cap, and in order to prevent the above-mentioned ink droplets from splashing from the space 13 due to ejection, the nozzle part of the inkjet head is usually covered with a cap. Ink droplets are ejected towards the area.

When the recording signal is input, the capping means 10 separates from the head, simultaneously starts the pump and starts the timer, and the head starts recording.

The pump only needs to operate for a few seconds to suck up the excess ink in the cap.

Even during recording, the viscosity increases due to drying if the nozzle does not eject, so after counting the time set on the timer, for example 5 minutes, when the carriage finishes recording one line and reaches a line feed, Move to the cap position and eject several pulses of ink droplets from all the nozzles toward the aforementioned space.In this case, recording is often in progress, and if we take the embodiment shown in Fig. 3. Ink is ejected while the DC solenoid 19 is energized and the cap 11 is retracted from the head. At the same time, the 6th
In the illustrated embodiment, the pump is activated to eject ink.

When the ink is ejected, the pump is stopped, the timer is reset, and the above-described operation is repeated until there is no recording command and the cap is completed. After capping, ink ejection stops and the timer is also reset.

In Figure 7, before the cap is opened and the head starts moving to the recording area, ink is always ejected from all nozzles toward the space inside the cap, so there is no need to worry about it during a short to long stop or pause. Excluding the effect of drying at the nozzle,
This prevents ejection failure during recording.

FIG. 8 schematically shows another embodiment of the capping means of the inkjet recording apparatus according to the present invention.
The figure is a flowchart of the operation. 25 is a valve,
The space 13 in the cap 11 is communicated with or cut off from the atmosphere through the tube 26. Normally, the space 13 inside the cap 11 is isolated from the atmosphere by a spring 27, and when the DC solenoid 28 is energized, it is communicated with the atmosphere.

In FIG. 7, the operation of ejecting ink toward the space during the cap oven has been described, but FIG. 9(a) shows a further modification of this. When a recording command is input to the inkjet head which is in the standby and capped state, first the valve 25 is turned on and the space inside the cap is communicated with the atmosphere. Next, while the pump is running, ink is ejected from all nozzles to discharge the ink whose viscosity has increased at the tips of the nozzles, and at the same time, a certain amount of ink, determined by the ink retention force of the absorber and the suction force of the pump, is released into the ink absorber. The inkjet head is then separated from the capping means, after which the valve is shut off from the atmosphere and the pump stops its suction operation.

FIG. 2B shows a state in which the space inside the cap is communicated with the atmosphere after ink is ejected, and suction is performed by a pump.

By configuring as shown in Fig. 8, the cap is separated from the head after the excess ink in the space inside the cap is sucked, so there is no need to worry about excess ink dripping from the space during the cap oven. became.

〔Effect of the invention〕

According to the present invention, the inside of the cap can be humidified with a small amount of ink ejected.

If ink is ejected to remove the effect of the increase in ink viscosity at the tip of the nozzle that occurs during the stop period, and if ink is ejected according to a scheduled sequence, ink can be used effectively and there is no need to forget about humidification. We were able to perform reliable humidification without any problems.

Furthermore, even if there is ink that cannot be contained in the ink absorber in the cap, the excess ink is absorbed, so even if the cap is opened, it will not drip and become dirty.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an embodiment of the main structure of an inkjet recording apparatus according to the present invention, FIGS. 2 to 5, and FIG. 8 are diagrams showing an embodiment of the capping means according to the present invention, and FIG. , FIG. 7, and FIGS. 9(a) and 9(b) are diagrams showing an embodiment of an operation flowchart of the recording apparatus according to the present invention. 2... Inkjet head 3... Carriage 9... Home position detection sensor 10... Capping means 11... Cap 12... Holding frame 13... Space portion 14... Ink absorber 15 ...Spring 19...Actuator 25...Valve and above Applicant Seiko Epson Co., Ltd. Agent Patent attorney Kisanbe Meiki and 1 other person Figure 4 2: Ing I-Tofudo 27: Tongue 1' 74 : Ink absorption book A Fig. 5 25: Halve Fig. 8 Fig. 9

Claims (4)

[Claims] (1) A capping means for covering a nozzle part of an inkjet head having a space inside it provided near a recording range and outside the recording range, an ink absorber installed in the space, and a capping means for covering a nozzle part of an inkjet head, which is provided in the vicinity of a recording range and outside the recording range; A suction means for sucking ink in the space to reduce the amount of ink in the space to an appropriate amount when the space is open to the atmosphere, and a drying prevention means for ejecting ink droplets toward the recording space. An inkjet recording device characterized by: (2) The inkjet recording apparatus according to claim 1, further comprising the drying prevention means for ejecting ink droplets toward the space when the recording apparatus is powered on. (3) While the power is turned on, the ejection of the ink droplets is stopped while the nozzle portion of the inkjet head is covered with the capping means, and when the capping means leaves the nozzle portion of the inkjet head, the ink droplets are removed. The inkjet recording apparatus according to claim 1, further comprising the drying prevention means for ejecting. (4) While the power is turned on, the ejection of the ink droplets is stopped while the nozzle portion of the inkjet head is covered with the capping means, and the ejection of the ink droplets is stopped almost regularly while the nozzle portion of the inkjet head is separated from the capping means. 2. The inkjet recording apparatus according to claim 1, further comprising the drying prevention means for ejecting ink droplets.