JP2002103643A - Ink supply mechanism for ink jet recording apparatus and ink injection tool suitable for the same - Google Patents

Abstract

(57) [Problem] To provide an ink supply mechanism that supplies ink while maintaining a negative pressure suitable for recording without requiring a porous material or the like. SOLUTION: An ink chamber 2, an air communication connection port 4 for maintaining the ink chamber 2 in a normally closed state, and an ink injection connection port 5, and an ink flow communicating with the ink chamber 2 and communicating with the recording head 59. An outlet 6 is formed, and an ink cartridge having a negative pressure generating mechanism 3 for discharging ink in the ink chamber 2 to the ink outlet 6 while maintaining a predetermined negative pressure state, and a connection port 4 for communicating with the atmosphere are opened. The concave portion 54 serving as a connection portion for communicating with the atmosphere via the capillary 57, the ink injection connection port 5 is accommodated in a closed state, and the ink injection connection port 5 is opened by inserting a syringe 60. Hole 55,
And a connection unit 50 connected to the ink outlet 6 to supply ink to the recording head 59.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink supply mechanism for an ink jet recording apparatus for supplying ink at a proper negative pressure to a recording head which discharges ink droplets in response to a print signal.

[0002]

2. Description of the Related Art In general, an ink jet recording apparatus is equipped with an ink jet recording head for discharging ink droplets in response to a print signal on a carriage which reciprocates in a paper width direction of a recording paper. It is configured to supply ink. Such an ink storage container such as an ink tank is detachably mounted on a carriage in a small recording apparatus, and is installed in a box in a large recording apparatus and is mounted on a box via an ink supply tube. Connected to the recording head.

The ink tank mounted on the carriage is
In order to reduce the pressure change due to the ripple of the ink due to the reciprocation of the carriage as much as possible, a porous material such as a sponge is usually accommodated and impregnated with the ink.

Further, even when ink is supplied from a large-capacity ink bag installed in a box via an ink supply tube, a change in ink pressure due to bending of the tube due to reciprocation of the carriage is prevented. Therefore, the ink is supplied to the recording head via a sub-tank having a damping function for preventing a change in the ink pressure due to the movement of the carriage.

[0005]

For this reason, in the former case, there is a problem that the size and weight of the ink tank are larger than the amount of ink that can be stored, because the porous material is stored. In the latter case, there is a problem that a mechanism for preventing a change in ink pressure due to swinging is required, and the structure is complicated. The present invention has been made in view of such a problem, and an object of the present invention is to maintain a negative pressure state suitable for printing regardless of the movement of a carriage and to supply ink of an ink cartridge to a recording head. An object of the present invention is to provide an ink supply mechanism for an ink jet recording apparatus that can supply ink. Another object of the present invention is to provide an ink injector suitable for the ink supply mechanism.

[0006]

In order to solve the above-mentioned problems, the present invention provides an ink chamber, a connection port for communicating with the atmosphere that keeps the ink chamber always closed, and a connection port for ink injection. A negative pressure generating mechanism for forming an ink outlet communicating with the recording head in communication with the ink chamber, and discharging the ink in the ink chamber to the ink outlet while maintaining a predetermined negative pressure state. A connection portion for opening the air communication connection port to communicate with the atmosphere through a capillary, the ink injection connection port being housed in a closed state, and a liquid injection means from outside. And a connection unit that connects to the ink outlet to supply ink to the recording head.

[0007]

When the ink cartridge is detached from the connecting means, the ink chamber is maintained in a sealed state by the valve body, thereby preventing ink leakage and evaporation of the ink solvent. In a state where the ink chamber is mounted on the connection means, the valve body is opened and the ink chamber is communicated with the atmosphere to supply the ink in the ink chamber to the recording head while maintaining a constant negative pressure. When the ink in the ink chamber is consumed, replace the ink cartridge or insert a liquid injection means such as a syringe into the ink injection port to forcibly open the ink injection connection port to open the ink chamber. Replenish the ink.

[0008]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram of a first embodiment of the present invention. FIGS. 1 to 3 each show an embodiment of the ink cartridge of the present invention. The ink cartridge 1 has an ink chamber 2 extending vertically in one side, and a negative pressure generator described later on the other side. Part 3
Are formed at the upper and lower portions of the ink chamber 2, respectively.
And a connection port 5 for ink injection, and an ink outlet 6 for supplying ink to the recording head is formed at the bottom.

Each of the connection ports 4 and 5 has communication windows 4a and 5a formed on the peripheral surface thereof.
Are movably accommodated in the axial direction. Each valve body 10, 2
0 indicates that one end 11a, 21a is connected to the connection port 4, 5 in the valve closed state.
On the other end sides of the slide shafts 11 and 21 protruding therefrom, packings 13 and 23 made of an elastic body for sealing the openings 12 and 22 communicating with the connection ports 4 and 5 are fitted. , 22 are inserted into the connection ports 4, 5 so that the packings 13, 23 are elastically contacted.

With this configuration, when the ink cartridge 1 is mounted on a connection unit 50 described later, the air communication connection port 4 maintains the valve open state, and the ink injection connection port 5 closes the valve state. , While the valve is opened when the ink injector is inserted.

As shown in FIG. 3, the negative pressure generating section 3 is provided in a valve chamber 30 having a circular concave section communicating with the ink chamber 2.
A membrane valve 31 and a flow path forming member 32 also serving as a fixture for fixing the outer periphery of the membrane valve 31 are housed therein, and the membrane 33 and 33 ′ having air shielding properties are attached to a region including the ink chamber 2. ing. A convex portion 34 is formed in the center of the valve chamber 30, and a through hole 35 is formed in the membrane valve 31 at a position facing the convex portion 34.

FIGS. 4 (a) and 4 (b) are views showing the ink flow paths formed in the negative pressure generating section 3 separately on the front and back sides.
The flow flowing from the through hole 37 into the through hole 39 of the valve chamber 30 via the flow path 38, the flow passing through the membrane valve 31, and the valve chamber 30
Through the flow path 43 connecting the through holes 40 and 41 with the through holes 41 and 42, and the through hole 4 communicating with the ink outlet 6.
4 and the through hole 42 are connected to each other by a flow flowing through a flow path 45 connecting the hole 4 and the through hole 42. Reference numeral 46 in FIG. 3 indicates a packing fitted into the ink outlet 6.

FIG. 5 shows a cross-sectional structure of the negative pressure generating portion 3. The membrane valve 31 is formed as a diaphragm having a thick portion around the periphery thereof.
Are in elastic contact with the convex portion 34. The elastic pressure of the spring 47 maintains the negative pressure of the ink applied to the recording head.
In addition, the setting is made such that ink can be supplied following the printing operation.

FIG. 6 shows an embodiment of the connection unit 50. The connection unit 50 is provided with a body 53 having walls 51 and 52 corresponding to the shapes of the front surface and the bottom surface of the ink cartridge. A recess 54 for accommodating the connection port 4, the connection port 5 for ink injection, and the ink outlet 6, a through hole 55, and a recess 56 are respectively formed.

A recess 54 engaged with the air communication connection port 4
Is open to the atmosphere via a capillary 57 formed on the surface of the main body, and a wall 54a for pressing the valve body of the atmosphere communication hole is formed inside. The through-hole 55 accommodating the ink injection connection port does not have a wall that comes into contact with the valve body of the ink cartridge, and keeps the valve closed. The concave portion 56 connected to the ink outlet 6 communicates with the recording head 59 via the communication hole 58.

In such a configuration, the ink cartridge filled with the ink is positioned with the ink outlet 6 in the concave portion 56 as shown in FIG. . Until the ink cartridge is attached to the connection unit 50, the membrane valve 31 maintains the closed state, so that the ink in the ink chamber 2 does not leak from the ink outlet 6,
Since the valve body 10 of the air communication connection port 4 maintains the closed state, the ink in the ink chamber 2 does not evaporate.

In the connected state, the slide shaft of the air connection port of the ink cartridge 1 is pushed by the wall and retreats against the spring to open the valve. As a result, the ink chamber 2 communicates with the atmosphere via the capillary 57. Further, the valve body 20 of the ink injection connection port 5 keeps the valve closed to prevent the leakage of the ink and the entry of the atmosphere.

In this state, if the recording head 59 is sealed with capping means and a negative pressure is applied to the recording head 59, the ink outlet 6 has a strong negative pressure.
Is opened, the ink in the ink chamber 2 flows into the recording head 59, and the recording head 59 is filled with ink.

On the other hand, when ink is consumed by the recording head 59 and the negative pressure at the ink outlet 6 increases, the membrane valve 31
The pressure difference between the front and back of the ink chamber 2 becomes large, so that the membrane valve 31 receiving the pressure of the ink in the ink chamber 2 separates from the convex portion 34 against the urging force of the spring 47. As a result, the through-hole 35 of the membrane valve 31 is opened, the through-hole 39 and the through-hole 42 communicate, and the ink outlet 6
Ink flows into. When the ink flows into the recording head and the negative pressure at the ink outlet 6 decreases, the membrane valve 31 is pressed against the convex portion 34 by the urging force of the spring 47, and the through hole 35 is sealed by the convex portion 34. Hereinafter, the membrane valve 31 is controlled so that the ink pressure at the ink outlet 6 becomes a constant negative pressure.
Repeats contact and separation with the convex portion 34.

When the ink in the ink cartridge 1 is consumed and the ink needs to be replenished, when the syringe 60 is inserted into the through hole 55, the valve body 20 is pushed by the tip end portion 60a of the syringe 60 and retreats. And open the valve. When the piston 61 of the syringe 60 is pressed in this state, the opening 60b
Flows into the ink chamber 2, and the compressed air in the ink chamber 2 due to the ink filling is released from the atmosphere communication connection port 4 to the atmosphere via the capillary 57.

When the syringe 60 is pulled out at the stage when the injection of a predetermined amount of ink has been completed, the valve body 20 loses support and closes due to the urging force of the spring 24 to prevent leakage of ink from the ink chamber 2. .

In the above embodiment, the ink is simply injected. However, by inserting an empty syringe to suck and discharge the ink in the ink chamber, and then injecting a specified amount of ink, By managing the ink consumption according to the print amount, the remaining amount of ink can be accurately determined.

In the above-described embodiment, the connection port 4 for communicating with the atmosphere and the connection port 5 for injecting ink are arranged above and below the ink chamber 2, respectively. The connection ports 4 and 5 can be provided at appropriate positions without being restricted by the arrangement position by communicating with a predetermined area of the ink chamber 2 through the interface.

[0024]

As described above, according to the present invention,
In a state where the ink supply means such as an ink cartridge is removed, the ink chamber is maintained in a sealed state by the valve body, thereby preventing ink leakage and evaporation of the ink solvent. Is opened, the ink chamber is communicated with the atmosphere, the ink in the ink chamber can be supplied to the recording head while maintaining a constant negative pressure, and further, when the ink in the ink chamber is consumed, The ink can be supplied to the ink chamber by replacing the ink cartridge or inserting a liquid injection means such as a syringe into the ink injection port.

[Brief description of the drawings]

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

FIG. 2 is a sectional view showing an embodiment of the ink cartridge according to the present invention.

FIG. 3 is an exploded perspective view of the ink cartridge.

FIGS. 4A and 4B are diagrams showing a flow of ink in a negative pressure generating section of the ink cartridge, respectively.

FIG. 5 is a diagram showing a cross-sectional structure of a negative pressure generating unit and a flow of ink in the same.

FIGS. 6A and 6B are a front view and a cross-sectional view, respectively, showing one embodiment of a connection unit.

FIGS. 7A to 7C are views showing a state in which an ink cartridge is attached to the connection unit, an ink injection step, and a structure of a tip end of a syringe, respectively.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Ink cartridge 2 Ink chamber 3 Negative pressure generation part 4 Air communication connection port 5 Ink connection port 6 Ink outlet 10, 20 Valve element 11, 21 Slide shaft 13, 23 Packing 14, 24 Spring 31 Membrane valve 50 Connection Unit 54 recess 54 a wall 55 through hole 56 recess 57 capillary 58 communication hole 59 recording head 60 syringe

Claims (2)

[Claims] 1. An ink chamber, an air communication connection port that maintains a normally closed state by communicating with the ink chamber, and an ink injection connection port, and ink that communicates with the recording head by communicating with the ink chamber. An ink cartridge having a negative pressure generating mechanism configured to discharge the ink in the ink chamber to the ink outlet while maintaining a predetermined negative pressure, and opening the air communication connection port. A connection portion for communicating with the atmosphere through a capillary, a through hole for accommodating the ink injection connection port in a closed state, and opening the ink injection connection port by inserting liquid injection means from outside. ,
And a connection unit connected to the ink outlet to supply ink to the recording head. 2. A main body capable of pressurizing and depressurizing a liquid,
An ink-tight end which is hermetically inserted into an ink-injection connection port of an ink cartridge and presses a valve of the ink-injection connection port to open the valve, and has a liquid flow path communicating with the main body. Injector.