JP2668457B2 - Ink jet recording device - Google Patents

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 apparatus applied to an ink jet printer.

An ink jet printer is a system in which minute particles of ink are directly sprayed onto a print medium such as recording paper from a print head which is not in contact with the print medium for recording. As a result, there are few restrictions on the print medium, and it is possible to easily realize colorization. In addition, high-speed recording,
It also has the characteristic of low noise.

[0003]

2. Description of the Related Art An outline of the structure of an ink jet printer which has been put to practical use is shown in FIGS. The structure and operation of these printers are as follows.

The ink jet printer shown in FIG. 5 includes a print head 1 and an ink tank 2 for supplying ink to the print head 1 on a carriage (not shown). Reference numeral 100 is a recording sheet on which the print head 1 faces. As the ink tank 2, a cassette-like replaceable one is usually used, and the capacity is 50 to 100 cc. Further, in the inkjet printer of FIG. 6, an ink cartridge (ink tank) 3 is provided in a place different from the carriage, and the ink cartridge 3 and the print head 4 are connected by a long ink supply tube 5 to supply ink. I am supposed to do it. 6 is the print head 4
Is a pressure damper installed at the entrance of the. However, these printers have the following disadvantages.

[0005]

In the structure shown in FIG. 5, since both the print head 1 and the ink tank 2 are mounted on the carriage, the carriage becomes heavy and the motor for driving the carriage also becomes large. Further, the structure of FIG. 6 requires the ink supply tube 5 for connecting the ink cartridge 3 and the print head 4 on the carriage, which makes the structure complicated and large, and when the carriage is scanned at high speed, Since the supply tube 5 is moved at high speed, the operation tends to be unstable. That is,
None of these methods can realize high-speed scanning of the carriage required for high-speed recording.

It is an object of the present invention to provide an ink jet recording apparatus having a simple structure and a small size and capable of high speed recording.

[0007]

In order to achieve the above object, according to the present invention, a print head and an ink sub-tank for supplying ink to the print head are provided on a carriage of an ink jet printer for recording by scanning the carriage. with mounting a, the ink refill station to replenish the ink in the ink subtank optionally, placed in the printer device other than the carriage Lee
Ink jet printer, the ink sub-tank
The ink supply port provided in the
The ink refill switch is
The inlet of the ink injection means of the station
Refilling ink in a state where it has broken through
And

In addition, the ink jet recording apparatus of the first configuration
The fluid is a magnetic fluid and a refill port
Characterized in that at least the periphery is made of a magnetic material
Configuration.

In addition, the ink jet recording apparatus of the first configuration
Fluid, glycerin or low saturated vapor pressure
Is a glycol-based liquid.
You.

[0010]

In any of the above constructions, the ink sub-tank on the carriage is replenished with ink from the ink replenishing station as needed, so that the ink sub-tank is filled with the minimum necessary amount of ink. You can leave it. As a result, the weight of the carriage can be reduced,
High-speed scanning becomes possible.

In the present invention, the evaporation of the ink is prevented.
To prevent this, supplement the ink provided in the ink sub tank.
In the normal state, the filling port is magnetic fluid or saturated vapor pressure.
Cover with low-glycerin or glycol-based liquid
Configuration compared to mechanical means such as a shutter
The advantages of easier manufacturing and lower manufacturing costs
And completely inside and outside the ink sub tank
As it can be sealed, it has excellent sealing performance.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS First, before explaining an embodiment of the present invention, FIG.
3 to 3, the ink replenishing sleeve which is the premise of the present invention.
An ink jet recording apparatus with a built-in station will be described.

FIG. 1 shows an ink replenishment step which is a premise of the present invention .
1 is a side view showing an outline of the structure of a built-in inkjet recording device, which is an outline of the structure of an embodiment of the present invention.
When exactly the same, 11 carriage, 12 is an ink refill station. A print head 13 and an ink sub tank 14 that supplies ink to the print head 13 are mounted on the carriage 11, and the liquid level of the ink in the ink sub tank 14 is
It is lower than the position of No. 3 nozzle. The print head 13 and the ink sub-tank 14 can be integrated into a unit configuration, and the unit can be detachable to facilitate maintenance.

The ink replenishing station 12 is provided with an ink replenishing tank 16 having an injecting pipe 15 and a pressure pump 17 for replenishing ink to the ink sub tank 14, and is provided in a printer device other than the carriage 11, for example, in the carriage 11. Proximity to home position (carriage 1
1 is a position where ink can be replenished to the ink sub-tank 14 when it reaches the home position).

The print head 13 reciprocates on the recording paper 100 by the reciprocating scanning of the carriage 11, thereby enabling printing. If you continue printing,
The ink in the ink sub tank 14 is being consumed. When the ink remaining amount in the ink sub-tank 14 becomes a certain amount or less, the print head 13 is returned to the home position by the ink remaining amount detecting means, and the ink is replenished from the ink replenishing station 12. The details will be described below. Is the street.

The remaining ink amount detecting means 18 is shown, for example, in Japanese Patent Application No. 2-188124 filed by the present applicant, and its structure is as shown in FIG. The ink remaining amount detecting means 18 is provided with a pair of electrodes 19 and 20, and when the ink liquid level in the ink sub-tank 14 becomes lower than the electrode 19, conduction between the electrodes 19 and 20 is lost. It is possible to detect the decrease in the remaining amount of ink by checking the resistance between 20. Reference numeral 21 denotes an electrode for detecting completion of ink replenishment.

When the remaining ink amount detecting means 18 detects a decrease in the remaining ink amount in the ink sub tank 14, the print head 13 is returned to the home position and the ink is replenished from the ink replenishing station 12.

The ink sub-tank 14 is provided with a replenishing port 22 as shown in FIG. 3, and the replenishing port 22 is closed by a shutter 23. Then, in the state where the print head 13 is returned to the home position as described above, the injection pipe 15 faces the refill port 22 as shown in FIG. 3 (A). Here, as shown in FIG. 3 (B), the shutter 23 is opened to connect the injection pipe 15 to the replenishment port 22.
And the pressurizing pump 17 is operated to replenish the ink. Completion of ink replenishment is detected by the electrodes 20 and 21, and the pressurizing pump 17 stops operating. After that, the injection pipe 15 is retracted from the ink sub tank 14, the shutter 23 is closed, and the print head 13 returns to the normal printing operation.

As described above, since the ink injecting portion of the ink sub-tank 14 is provided with the open / close shutter 23 and the shutter 23 is closed except when the ink is replenished, the evaporation of ink does not occur. The capacity of the ink sub tank 14 is
In the case of a normal printing operation, 5 cc is sufficient, and the weight saving of the ink sub tank 14 is realized. Therefore, the carriage becomes light in weight, and since it is not necessary to draw around an ink supply tube or the like, it is possible to perform high-speed scanning of the carriage required for high-speed printing. Further, the ink replenishing tank 16 of the ink replenishing station can be provided with sufficient ink of about 60 cc. The ink capacity of the ink replenishment tank 16 can be increased if necessary.

Next, an actual printing result by this ink jet recording apparatus will be described. 3 as print head
Using a 50 nozzle head for 00 dpi, using a monochrome ink having a surface tension of 60 dyn / cm and a viscosity of 5 cp, the printing operation was performed at a particleization frequency of 5 kHz, a carriage scanning speed of 0.46 m / s, and an ink amount of the ink sub tank of 5 cc. As a result, the printing was excellent even after continuous printing for a long time. Further, even if the ink in the ink sub-tank was consumed and ink was replenished, the printing stability was not impaired. Furthermore, 120 sheets of A4 size document could be printed by replenishing the ink once.

Next, based on the above assumptions, FIG.
Open and close the refill port 22 of the ink sub tank 14 with reference to
An embodiment of the present invention using a magnetic fluid as a means will be described.
However, the configuration other than the opening / closing means is the same as that shown in FIGS. 1 and 2.
In exactly the same way, in the figure, reference numeral 24 denotes a magnetic fluid.
At least a portion of the ink sub-tank 14 around the refill port 22 is formed of a magnetic material, and the magnetic fluid 24 normally forms a film to close the refill port 22.

When it is detected that the remaining amount of ink in the ink sub-tank 14 is low, the print head returns to the home position as described above, and the injection pipe 15 faces the refill port 22 as shown in FIG. 4 (A). Injection pipe 1 from this state
5 is lowered, the injection pipe 15 penetrates the magnetic fluid 24 as shown in FIG. 4B, and ink replenishment is performed in this state. When the injection pipe 15 is pulled up after the ink replenishment is completed, the magnetic fluid 24 closes the replenishment port 22 as before.

As described above, in the present invention, the ink
To prevent evaporation, the ink sub-tank
Under normal conditions, cover the refill port with magnetic fluid.
Configuration and configuration compared to mechanical means such as a shutter
It will be easier to operate and lower in manufacturing cost.
It has advantages and completes the inside and outside of the ink sub tank.
Because it can be completely sealed, it has excellent sealing properties.

A non-magnetic fluid can be used instead of the magnetic fluid 24. As a non-magnetic fluid,
A glycol-based liquid or glycerin having a low saturated vapor pressure can be used. To support colorization, a plurality of sets of print heads, ink sub-tanks, and ink replenishment stations may be provided so as to be compatible with a plurality of colors of ink.

[0025]

As described above, according to the present invention, since the ink sub-tank on the carriage is replenished with ink from the ink replenishing station as needed, the ink sub-tank needs the minimum necessary amount. You should put the limit ink. As a result, the weight of the carriage can be reduced and high-speed scanning can be performed. Moreover, the structure of the device is simple and small.

Further , in the present invention, the ink subtan
In the normal state, the ink supply port provided in the
Fluid, glycol-based liquid or glycerin
Since it is covered, the mechanism and operation of opening and closing the refill port
It can be simplified and the manufacturing cost can be reduced.

Further, if the ink sub-tank is constructed integrally with the print head, these can be handled as a unit, and if this unit is made replaceable,
Maintenance becomes easy.

Further, if the ink remaining amount in the ink sub tank is detected and the ink is replenished, effective ink replenishment becomes possible. In addition, the ink can be replenished when the carriage reaches the home position (the ink replenishment station is located close to the home position).
By doing so, efficient ink supply is realized.

Further, if a plurality of sets of print heads, ink sub-tanks, and ink replenishing stations are provided so as to be compatible with a plurality of colors of ink, colorization can be supported.

[Brief description of the drawings]

FIG. 1 is a side view showing an outline of the structure of an inkjet recording apparatus according to an embodiment of the present invention.

FIG. 2 is a configuration of an ink remaining amount detecting means according to an embodiment of the present invention,
FIG.

FIG. 3 is a shank as a replenishing port opening / closing means which is a premise of the present invention.
An ink supply procedure explanatory view of the ink subtank when using jitter, 3 (A) shows a state in which the injection pipe is opposed to the replenishing port, enters the FIG. 3 (B) injection pipe in the ink subtank It shows the state of being done.

FIG. 4 is an explanatory view of the refilling port opening / closing means of the embodiment of the present invention, FIG. 4 (A) shows a state in which the injection pipe faces the refilling port,
FIG. 4B shows a state in which the injection pipe has entered the ink sub tank.

FIG. 5 is a side view showing an outline of the structure of a conventional inkjet printer.

FIG. 6 is a side view showing an outline of the structure of another conventional inkjet printer.

[Explanation of symbols]

11 Carriage 12 Ink Replenishing Station 13 Print Head 14 Ink Sub-Tank 15 Filling Pipe 18 Ink Remaining Detecting Means 22 Replenishing Port 24 Magnetic Fluid

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-2-63746 (JP, A) JP-A-62-290544 (JP, A)

Claims (3)

(57) [Claims] 1. A print head and an ink sub-tank for supplying ink to the print head are mounted on a carriage of an inkjet printer for recording by scanning the carriage, and ink is replenished to the ink sub-tank as necessary. Inkjet printers that have an ink replenishment station inside the printer device other than the carriage
The ink supply port provided in the ink sub tank is
In the normal state, it is blocked by the fluid, and when the ink is replenished ,
With the injection port of the injection means piercing through the fluid layer,
An ink jet recording apparatus for replenishing ink. 2. The method according to claim 1, wherein the fluid is a magnetic fluid,
That at least the periphery of the refill port is made of a magnetic material
The ink jet recording apparatus according to claim 1, which is characterized in that. 3. The fluid is glycerin having a low saturated vapor pressure.
Contracts characterized by liquid or glycol-based liquids
The inkjet recording apparatus according to claim 1.