JPS5964361A - Ink supply apparatus of ink jet recording apparatus - Google Patents

Abstract

PURPOSE:To make it possible to smoothly perform the jet flight of an ink droplet, by mounting an air buble trap chamber in an ink cartridge. CONSTITUTION:An ink cartridge 2 for supplying recording ink to an ink jet recording apparatus is constituted from an ink receiving bag 3 made of a flexible material filled with ink 2 to be replenished, an enclosure 4 with a rigid structure for mounting said bag 3 therein, a cap member 5 fixedly provided to one opening part of said enclosure 4, an elastic member 6 for preventing the outflow of the ink 2 to be replenished filling said cap or the inflow of air from the outside and enabled in the insert and piercing of a hollow needle and a trap assembly 7 connected to the opening part of the ink receiving bag 3 in a hermetically sealed state at one end thereof while connected to the cap member 5 in an air-tight manner at the other end thereof and having an ink sump at the intermediate part thereof. The trap assembly 7 is constituted from an ink flowline 8 communicated with the ink receiving bag 3, a trap chamber 9 and an outlet flowline 10.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an ink cartridge used in an inkjet recording device that replenishes recording ink using a cartridge method, and particularly relates to an ink cartridge for removing air bubbles or dissolved gas generated in the ink in the ink cartridge. The present invention relates to an ink cartridge containing a built-in means for doing so.

An inkjet recording device records characters, figures, etc. on a recording surface by ejecting small droplets of ink from a narrow nozzle. In this case, in order to draw high-quality characters, figures, etc., fine ink droplets of equal diameter must be regularly and intermittently ejected. In order for these ink droplets to fly smoothly and to stably draw characters, figures, etc. on recording paper, the properties of the ink itself must be sufficiently uniform and stable. At the same time, it is necessary to prevent air bubbles from entering the ink flow path from the ink tank to the recording head.

Generally, in an inkjet recording device, the ink tank of the ink supply device is used to replenish ink to the recording head.In order to keep the ink in a stable state ((( An ink cartridge is used.The ink cartridge is filled with ink in a highly airtight bag or container to prevent air from entering.The ink cartridge is removably attached to the cartridge holder. , new ink can be refilled by replacing the ink cartridge.

In an inkjet recording device using such an ink cartridge, air bubbles generated in the ink in the ink cartridge or gas dissolved in the ink enter the recording head through an ink supply pipe and eject ink droplets. This causes clogging of fine-diameter nozzles. This may cause non-ejection or unstable ejection of ink droplets, and reduce the ejection efficiency.
This results in a decrease in jetting accuracy such as stability and responsiveness of ink droplet formation. In particular, pressurize the ink from the ink cartridge.
An inkjet recording device (for example, Japanese Patent Publication No. 53, -121
No. 38), the adverse effects of air bubbles in the ink as described above are significant. Therefore, it is essential to completely remove air bubbles generated or mixed into the ink cartridge.

The causes of air bubbles being generated or mixed into the ink cartridge include the following.

(1) A small amount of air bubbles may remain during the manufacturing process of filling the ink cartridge with ink.

(2) Gas dissolved in the ink is leached out and becomes bubbles, which are mixed into the ink.

(31) When the ink cartridge is attached to or removed from the receiver of the recording device, outside air enters through the connection.

(4) Air bubbles generated or remaining in the ink supply pipe and the above-mentioned receiver enter the ink cartridge.

(5) A small amount of outside air enters the mouth of the ink cartridge.

Conventionally, various methods have been used to remove air bubbles generated or mixed into an ink cartridge due to the above-mentioned causes. These methods will be explained below using conventional examples.

(Al) A bubble trap device is provided in a part of the ink supply path to communicate the ink cartridge and the recording head, and this trap traps air bubbles mixed into the ink.
-67471 Publication, JP-A-52-150028 @
) (b) A heating means is provided in a part of the ink supply path to grow microbubbles, float them, and collect them. (Unexamined Japanese Patent Publication No. 55-
128463) FC+ A vibration means is provided on a part of the inner wall surface of the recording head or a part of the ink supply path to forcibly collect air bubbles attached to the inner wall surface or air bubbles contained in the ink. (JP-A-55-71567, JP-A-55-=67471
(Patent Publication) td) A stirring means or a pressure reducing means is provided in a part of the ink supply path, and the dissolved gas in the ink is grown and liberated by these means and collected.

(el) If a drop in jetting characteristics is detected due to air bubbles or other causes, the ink flow path is filled with a cleaning liquid that dissolves air bubbles to remove the air bubbles, and then new ink is introduced to replace the ink.

The above-mentioned air bubble removal devices are all installed on the main body of the inkjet recording device, and when the gas collected by the air bubble removal device accumulates (and is discharged by some method), the gas is removed from the collection container. Therefore, the bubble removing device and the collecting means become complicated and large, and an extra operation for discharging or replacing them is required, which is troublesome.

As mentioned above, all methods for removing air bubbles mixed into the ink in the ink cartridge and gas dissolved in the ink using conventional ink cartridges have problems in terms of structure, operation, cost, stability, etc. It is still insufficient.

The present invention has been made to solve each of the above-mentioned problems, and has a replaceable ink cartridge with a built-in air bubble removal means, so that the collected gas can be removed when refilling the ink. Even those that provide ink cartridges7-
I.

That is, the present invention is characterized in that the ink cartridge of the Niro ink cartridge recording apparatus is provided with an air bubble trap chamber for collecting air bubbles inside the ink cartridge.

A preferred embodiment of the ink cartridge of the present invention is characterized in that the ink cartridge is provided with one or both of excitation means using a vibrator and heating means using a heating element in the vicinity of the bubble trap chamber. It is characterized by the fact that it is equipped inside.

Furthermore, another embodiment of the IJ nozzle (ink car of the present invention) is characterized in that temperature detection means is provided close to the heating means provided near the bubble trap chamber to control the temperature. be.

Furthermore, a feature of still another embodiment of the ink cartridge of the present invention is that when the ink cartridge is installed in the main body of the recording apparatus, the ink cartridge main body is provided with means for preventing erroneous installation so that the ink cartridge can be installed in a fool-proof manner. It is characterized by:

In addition to the above features, the main effects achieved using the ink cart according to the present invention are as follows.

(b) The volume of the bubble trap chamber is ink cartridge 1
Since the maximum gas volume contained in the individual is sufficient, an extremely small volume is sufficient.

(b) At the same time as the ink cartridge is replaced, the bubble trap chamber inside the ink cartridge is replaced as a whole, so complicated operational errors such as evacuation from the bubble trap chamber and replacement of the bubble/wrap chamber may occur. There's nothing to do.

(c) Since the bubble trap chamber of the present invention is disposable together with the ink cartridge each time, there is no need for a complicated device for detecting and warning the accumulated gas volume f& in the bubble trap chamber.

・21 An embodiment of the ink cartridge of the present invention not only collects air bubbles, but also actively collects gases dissolved in the ink by growing and releasing them, and after this process is completed, recording is performed. The ink that is fed into the head rarely generates bubbles.

(The bubble trap chamber, heating means, excitation means, etc. provided in the ink cartridge of the Ho IX invention have a small and simple structure 6τ, so even if it is disposable when replacing the ink cartridge, the cost is minimal.) Make sure it's limited to one.

The present invention will be explained in detail below with reference to the drawings.

FIG. 1 is a sectional view of an ink cartridge showing an embodiment of the present invention.

The ink cartridge 1 includes an ink storage bag 3 made of a flexible material filled with refill ink 2, a cart IJ housing 4 having a rigid structure and housing the ink storage bag 3, and this cartridge rich housing. 4, and a cap member 5 that is filled in the interior of the cap member 5 to prevent the replenishing ink 2 from flowing out and gas from entering from outside, and a hollow needle described later can be inserted and penetrated therethrough. a trough/bore assembly 7 having one end hermetically connected to the opening of the ink storage bag 3, the other end hermetically connecting to the cap member 5, and having an ink reservoir therebetween; It consists of

The trap assembly 7 is inserted into the ink storage bag 3.
It consists of an ink flow path 8, a trap chamber 9, and an outlet flow path 10. The ceiling of the exit flow path]0 is sloped so as to become higher toward the northern part of the trap chamber 9. The trap chamber 9 is shaped so that bubbles generated in the outlet flow path 0 can easily float to the upper part of the trap chamber 9 through this inclined surface.

Incidentally, since the air hole 4A is opened in a part of the cartridge housing 4 and communicates with the outside air, the pressure of the ink in the ink storage bag 3 is equal to the atmospheric pressure.

On the other hand, a connector 2 is fixedly attached to one end surface of the ink cartridge loading part of the inkjet recording apparatus σ). Approximately at the center of this connector 21, a hollow needle 22 for inserting an IJ switch is provided, which has a very narrow ink flow path. When the ink cartridge 1 is loaded and connected to the connector 21,
This needle 22 ÷ passes through the stomach of the elastic member 6 of the ink cartridge 1 to the outlet channel 10 of the trap assembly 7.
It reaches inside and communicates with the replenishment ink 2. , the other end of the hollow needle 22 communicates with the ink flow path in the recording head 25 via an ink supply pipe 23 and a filter 24, so that atmospheric pressure, ink pressure, and surface tension maintain an equilibrium state in the nozzle 26. I have IL.

When the ink cartridge is new and filled with ink, the inside of the trap chamber 1) is completely filled with ink. There is a small amount of air bubbles that remain unabsorbed. By loading the ink cartridge 1 into the recording apparatus, the ink 2 in the ink storage bag 3 passes through the hollow needle 22 and is connected to the recording head 25.
The ink supply is fully supplied 'V'.

When this ink cartridge is loaded, the air trapped near the tip 4 of the hollow needle 22 is in the liquid in the outlet passage 10 of the trap assembly 7? It floats up and rises along the upper slope, reaches one part of the trap chamber 9, and is collected there.

When ink droplets are ejected from the nozzles 26 of the recording head 25 and ink is consumed, the replenishment ink in the ink storage bag 3 flows out and is supplied by hydrostatic pressure. The air bubbles that are generated and separated from the gas dissolved in the ink pass through the ink flow path 8, float in the ink in the trap chamber 9, reach the upper part, and are supplemented there. Gather yourself.

In this way, when the ink cartridge 1 is loaded, both the air bubbles mixed in when the hollow needle 22 is inserted and the air bubbles inside the ink storage bag 3 are collected in the upper space of the trap chamber 9. There are no words that flow to the recording head side.

Next, in the present invention, by providing the sensor 11 on the outer wall of the ink flow path 8 forming a part of the trap assembly 7, the bubble trapping effect is further improved.

The vibrator 11 is an electromechanical transducer, also called a transducer, and there are two types: a piezoelectric type sensor and a magnetic type sensor. As the piezoelectric sensor, a piezoelectric crystal, a ceramic sensor, etc. are used. Metal magnetostrictive vibrators and ferrite sensors are known as magnetostrictive elements. The above-mentioned vibrator 11, for example, the outer and inner walls of a cylindrical piezoelectric crystal are used as conductive electrodes 2, and the inner wall is brought into close contact with the outer wall surface of the ink flow path 8 of the trap assembly 7 by a 4-conductor thin film. and glue. The 'electrodes' of the above-mentioned camera element are fixedly attached to the cartridge housing 4 and connected to the Muni connection electrodes 2 by respective leads I%j13.

On the other hand, in the ink car of the recording device, there are
A connection electrode 14 is fixedly provided at a position facing the connection electrode 12, and is electrically connected to a drive circuit 15 that excites the vibrator 11.

Therefore, by loading the ink cartridge 1 into the receiver of the recording device, the ink path from the ink storage bag 3 to the recording head 25 is communicated with the outer wall surface of the trap assembly 7. The electrodes of the vibrator 11 are electrically connected to a drive circuit 15 via connecting wires 12 and 14.

In this connected state, the ink flow path 8 of the trap assembly 7 is driven by driving the drive circuit 15 to excite the vibration +H while the recording device is powered on, during printing operation, or intermittently. Dissolved gas in the ink flowing therein is precipitated and liberated by cavitation, and air bubbles are floated and collected in the upper space of the trap chamber 9.

By performing this forced air bubble collection within the ink cartridge, generation of air bubbles within the recording head 25 is prevented.

Note that the vibration frequency of the vibrator 11 must be within an appropriate range that can reliably liberate dissolved gas and collect bubbles. This is because, depending on the vibration frequency of the pulsator, the opposite effect may occur in that the air in the upper space in the trap chamber 9 or the bubbles in the ink are dissolved into the ink.

FIG. 2 is a cross-sectional view of an ink cartridge showing an embodiment (A+ indicates the invention and Q).

An iranbu assembly 30 is fixedly provided between the opening of the ink storage bag 3 and the cap member 5. The trap assembly 30 has an ink flow path 31 that flows into the ink storage bag 3.
, a trap chamber 32 , and an outlet flow path 32 .

Second figure 1 ((3) shows a horizontal sectional view of the trap chamber 32.

Trap chamber 32θ) The horizontal cross-sectional shape is a long rectangular chamber (y), and a flat plate-shaped vibrator 34 having *poles 33 on both sides is adhered to one surface of the outer wall forming the long side. The polarization 33 of this vibrating force element 34 is connected to the drive circuit 15 through a lead wire 35.

By driving this 1 state 11ff + giant 1 road] 5, the vibrator 34 is vibrated, and the bath enters the ink in the trap chamber 32. The dissolved gas is caused to cavitate, and is precipitated and liberated as bubbles. Float and trap chamber 32
Collect it in the space above.

Another embodiment of the present invention is shown in Fig. 2 of F77K ((1)
1-0 No. 21 (11C) also shows the horizontal cross section V1 of the trap chamber 32 in FIG. A front-moving vibrator 3 is mounted on one side of the outer wall that forms the long side.
4 is adhered together with the double-sided electrode 33. A heating element 36 is attached to the other outer wall surface forming the opposing long sides.

The heating element 36 can be a flat heater such as a printed heater or a planar heater, or a heater of various other shapes. These heating elements are electrically connected to a power source (not shown).

Furthermore, a temperature sensor 37 is attached to the central portion of the heating element. As the temperature sensor 37, a thermistor or the like is generally used.

The heating element 36 is powered by current from a power supply (not shown).
The heat generated 17 heats the wall of the trap chamber 32 that is in close contact with it, raising the temperature of the ink inside. The temperature sensor 37 controls the temperature of the heating element 36 to be kept constant.

By using the heating element 36 and the vibrator 34 in combination, the temperature rise of the ink caused by the heating element 36 is excited by the vibrator 34, and when the dissolved gas in the ink is precipitated, the bubble-precipitating effect is The temperature sensor 37 serves to maintain the temperature of the heating element 36 within a predetermined limit. Although it is for controlling the temperature, if the difference in outside air temperature can be ignored, the temperature sensor 37 for temperature control becomes unnecessary if a constant gravity is always applied.

FIG. 3 is an external perspective view of an ink car (1) Azalea showing still another embodiment of the present invention.

The outer wall of the cartridge housing 4 of the ink cartridge 1 includes a cap member 5 including an elastic member 6 for connecting and forming an ink distribution path, a camera, a heating element, an external drive circuit,
A connection electrode 12 is attached for connection to a power source.

When loading the ink cartridge 1 into the recording apparatus, it is necessary to insert the ink cartridge 1 in the vertical, front-back, left-right direction without fail in a predetermined direction. A reliable connection cannot be made unless it is inserted accurately to avoid loosening or misalignment. The present invention provides an easy and convenient operation of the ink cartridge loading section by installing a bracket 40 on the bottom surface of the car) and installing a shoe (not shown) that fits into the insertion section on the recording apparatus main body side. I did it correctly.

This bracket may be installed in an asymmetrical shape or position.The insertion portion and the other end of the racket 40 may have different shapes to make it impossible to insert the racket into a reverse position. In addition, the bracket 40 and the shoe are fitted together without any play (
・For easy insertion, it is recommended to provide an inclined surface on the introduction part of the bracket 40 or the shoe. Furthermore,)
It is possible to take various precautions, such as removing looseness in the fitting portion by pressure-welding using a nail or the like.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of an ink cartridge showing an embodiment of the present invention, Fig. 2 is a sectional view of an ink cartridge showing another embodiment of the invention, and Fig. 3 is a sectional view of an ink cartridge showing another embodiment of the invention. It is a perspective view of an ink cartridge showing 1... ink cartridge, 2... ink, 3...
・Ink storage bag, 4...Cartridge housing, 5...
Cap member, 7, 3 (1... Trap assembly, 8, 3
]... Ink channel, 9, 32... Trap chamber, 1.
(1, 32... Outlet channel, 11, 34, Vibrator, 1
．． 2, 14... Connection electrode, 15... Drive circuit, 2]
... connector, 22 ... hollow needle, 25 ... distribution head, 36 ... heating element, 27 ... temperature sensor, 40 ... bracket. Agent Yoshimi Kuwahara

Claims (1)

[Claims] (1) A cart 1 with a removable and removable function for replenishing recording ink.
An ink cartridge for an ink jet recording apparatus using an ink cartridge, characterized in that the ink cartridge (11) is equipped with an air bubble trap chamber inside the ink cartridge (11). (2. σ as stated in Claim 1) In an ink cartridge, the provision of a means with a smaller force (or less than 1) of the excitation means or heating means in the vicinity of the bubble trough chamber σ is defined as standby. (3) The ink cartridge according to claim 2, characterized in that a temperature detection means is provided in the vicinity of the heating means (4) The ink cartridge according to claim 2 The ink cartridge described in [Range Ryo 1st term - 3rd term σ] is characterized by being equipped with a means to prevent incorrect installation on a part of the ink cartridge. Ink cartridge.