JP2003127412A - Ink supply unit and printer head - Google Patents

Abstract

PROBLEM TO BE SOLVED: To stably hold ink without leaking the ink while making an ink storage amount large and the structure simple. SOLUTION: There are provided an ink storage part 20, an ink chamber 51 coupled to the ink storage part 20 so that ink in the ink storage part 20 can flow down, and a valve 52 which is excited to shut between the ink storage part 20 and the ink chamber 51 and is moved to make the ink storage part 20 and the ink chamber 51 communicate with each other by a pressure decrease in the ink chamber 51 generated when ink is supplied from an ink send-out part 54 of the ink chamber 51. The ink storage part 20 is provided with an outdoor air communication hole 42a which is formed to communicate with the outdoor air for taking inside the air of an amount corresponding to a reduction amount of the quantity of ink when the quantity of ink reduces because the ink is sent from the ink storage part 20 to the ink chamber 51.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink supply device for sending out a predetermined amount of ink from an ink containing portion to the outside, and a printer head to which the ink supply device is applied.

[0002]

2. Description of the Related Art As an ink supply device used in a conventional printer head, for example, the following are known. FIG. 13 is a diagram showing a first example of a conventional ink supply device of this type. In FIG. 13, the ink containing portion 101
Is partitioned into an ink tank 101a and an ink holding chamber 101b. The bottom surface portion communicates between the ink tank 101a and the ink holding chamber 101b.

Ink is loaded on the ink tank 101a side. An outside air communication hole 102 that communicates with the outside air is formed on the top surface side of the ink holding chamber 101b. Furthermore, a porous body 103 for holding ink is provided in the ink holding chamber 101b. Further, an ink delivery section 104 is formed on the bottom surface side of the ink holding chamber 101b.

When the ink is sent out from the ink sending unit 104, air enters the ink tank 101a side, and the ink corresponding to the air is sent from the ink tank 101a to the ink holding chamber 101b side and the porous body 1
Held at 03. Here, due to the capillary force of the porous body 103, a force in the suction direction is applied to the ink. As a result, ink does not leak from the ink delivery unit 104.

FIG. 14 is a diagram showing a second example of a conventional ink supply device. In FIG. 14, the ink containing portion 105
On the bottom face side of the ink delivery unit 10 as in the first example.
4 are formed. Further, inside the ink containing portion 105, a bag-like body 106 containing ink inside is provided. A force is constantly applied to the bag-shaped body 106 by a spring 107 in a direction to expand the bag-shaped body (direction of arrow in FIG. 14). Due to the force of the spring 107, the ink in the bag-shaped body 106 is applied with a force in the suction direction. As a result, ink does not leak from the ink delivery unit 104 as in the first example.

As described above, the ink supply device used in the printer head is constructed so that the ink does not leak from the ink delivery section 104.

[0007]

However, the above-mentioned conventional techniques have the following problems. In the first example, since the porous body 103 is provided in the ink holding chamber 101b, the volume in the ink supply device is reduced by the amount of the porous body 103. Therefore, there is a problem that the amount of ink that can be accommodated inside is small relative to the size of the entire ink supply device.

Further, in the second example, since the spring 107 is used, when the ink containing portion 105 is made thin, for example, the spring 107 cannot be housed inside the bag-shaped body 106, There is a manufacturing problem such as a complicated manufacturing process. Further, since the spring 107 is used, there is a problem that the mechanism becomes complicated and the cost becomes high.

Therefore, the problem to be solved by the present invention is to make it possible to hold ink stably, with a large ink storage capacity, a simple structure, and no ink leakage.

[0010]

The present invention solves the above-mentioned problems by the following solving means. The invention according to claim 1 has an ink containing portion and an ink sending portion which is arranged below the ink containing portion and which is connected to the ink containing portion so that ink in the ink containing portion can flow down and sends out ink. An ink chamber for opening and closing the ink chamber and the ink chamber, and being urged to close the space between the ink chamber and the ink chamber, the ink chamber A valve that is moved so that the ink storage portion and the ink chamber communicate with each other due to a decrease in pressure in the ink chamber that occurs when ink is supplied from the ink delivery portion of the ink storage portion. When the ink amount is decreased by being sent to the ink chamber from the ink containing portion, the amount corresponding to the decrease amount of the ink amount is formed so as to communicate with the outside air. An ink supply device characterized by comprising outside air communication hole for taking in air therein.

According to a second aspect of the present invention, in the ink supply device according to the first aspect, the ink containing portion includes an ink tank, and a nozzle portion extending below the ink tank.
An ink reservoir into which at least a lower end of the nozzle portion enters, the valve opens and closes between the ink chamber and the ink reservoir, and the outside air communication hole is formed in the ink reservoir. When the valve is moved so that the ink reservoir and the ink chamber communicate with each other due to a decrease in pressure in the ink chamber, the amount of ink in the ink reservoir decreases and the outside air communication hole From the above, air is introduced into the ink tank through the nozzle portion, and the ink flows down from the ink tank to the ink reservoir portion.

According to a third aspect of the present invention, in the ink supply device according to the first aspect, the ink containing portion is formed to be removable.

According to a fourth aspect of the present invention, in the ink supply device according to the first aspect, the ink containing portion includes an ink tank, and a nozzle portion extending below the ink tank.
An ink reservoir into which at least a lower end of the nozzle portion enters, the valve opens and closes between the ink chamber and the ink reservoir, and the outside air communication hole is formed in the ink reservoir. When the valve is moved so that the ink reservoir and the ink chamber communicate with each other due to a decrease in pressure in the ink chamber, the amount of ink in the ink reservoir decreases and the outside air communication hole From the ink through the nozzle portion into the ink tank, the ink flows down from the ink tank to the ink reservoir portion, the ink tank is removable from the ink reservoir portion. It is characterized by being formed.

The invention of claim 5 is from claim 1 to claim 4.
In the ink supply device according to any one of items 1 to 5,
The valve is provided in the ink chamber and is biased toward the ink containing portion by a biasing member.

According to a sixth aspect of the present invention, there is provided a printer head including an ink supply device and a printer head chip, wherein the ink supply device is arranged below the ink containing portion and the ink containing portion. An ink chamber that is connected to the ink storage unit such that the ink in the ink storage unit can flow down and has an ink delivery unit that sends out ink, and for opening and closing between the ink storage unit and the ink chamber, The ink is urged so as to close the space between the ink storage portion and the ink chamber, and the pressure in the ink chamber decreases when ink is supplied from the ink delivery portion of the ink chamber, whereby the ink A valve that is moved so that the container and the ink chamber communicate with each other;
The ink containing portion is formed to communicate with the outside air,
When the ink amount decreases due to the ink being sent from the ink storage section to the ink chamber, an outside air communication hole is provided for taking in air corresponding to the decrease in the ink amount. In the printer head chip, a plurality of ink pressurizing chambers each having a heating resistor and communicating with the ink chamber of the ink supply device are arranged side by side on a substrate, and the heating resistor is driven, so that the ink It is characterized in that the ink in the pressure chamber is ejected from the nozzle.

According to a seventh aspect of the present invention, in the printer head according to the sixth aspect, the ink containing portion of the ink supply device includes an ink tank, a nozzle portion extending below the ink tank, and the nozzle. An ink reservoir into which at least the lower end of the portion enters, and the valve opens and closes between the ink chamber and the ink reservoir,
The outside air communication hole is formed in the ink reservoir, and when the valve is moved so that the ink reservoir communicates with the ink chamber due to a decrease in pressure in the ink chamber, the ink reservoir Due to the decrease in the amount of ink in the portion, air is introduced from the outside air communication hole through the nozzle portion into the ink tank, and the ink flows down from the ink tank to the ink reservoir portion. Characterize.

According to an eighth aspect of the present invention, in the printer head according to the sixth aspect, the ink containing portion of the ink supply device is detachably formed.

According to a ninth aspect of the present invention, in the printer head according to the sixth aspect, the ink containing portion of the ink supply device includes an ink tank, a nozzle portion extending below the ink tank, and the nozzle. An ink reservoir into which at least the lower end of the portion enters, and the valve opens and closes between the ink chamber and the ink reservoir,
The outside air communication hole is formed in the ink reservoir, and when the valve is moved so that the ink reservoir communicates with the ink chamber due to a decrease in pressure in the ink chamber, the ink reservoir Due to the decrease in the amount of ink in the portion, air is introduced from the outside air communication hole through the nozzle portion into the ink tank, and the ink is configured to flow down from the ink tank to the ink reservoir portion. The ink tank is formed so as to be detachable from the ink reservoir.

According to a tenth aspect of the invention, in the printer head according to any one of the sixth to ninth aspects, the valve of the ink supply device is provided in the ink chamber, and the valve is energized. It is characterized in that it is urged toward the ink containing section by a member.

(Operation) In the invention of claim 1 or 6, when the ink is supplied from the ink delivery portion of the ink chamber, the pressure in the ink chamber decreases. As a result, a suction force for pulling the ink is generated in the ink chamber, the valve is moved by the suction force, the ink storage portion and the ink chamber communicate with each other, and the ink is sent from the ink storage portion to the ink chamber.

When the ink is sent from the ink containing section to the ink chamber, the amount of ink in the ink containing section is reduced, but the air corresponding to this decrease is taken into the ink containing section from the outside air communication hole. Further, when the pressure in the ink chamber returns to a steady state due to the ink being sent from the ink containing unit to the ink chamber, the valve closes the gap between the ink containing unit and the ink chamber. As a result, the feeding of ink from the ink containing section to the ink chamber is stopped.

Therefore, since the porous body for holding the ink is not provided in the ink containing portion, the ink containing amount can be increased. Further, instead of using a spring or the like to reduce the pressure in the ink containing portion, gas-liquid exchange is performed between the ink containing portion and the ink chamber, and a valve opens and closes the ink containing portion and the ink chamber. Therefore, the structure can be simplified. In addition, the ink can be stably held without ink leakage.

In the invention of claim 2, claim 4, claim 7 or claim 9, when the ink is supplied from the ink delivery portion of the ink chamber, the valve is provided between the ink chamber and the ink reservoir. Open. As a result, ink is sent from the ink reservoir to the ink chamber. When ink is sent from the ink reservoir to the ink chamber, the amount of ink in the ink reservoir decreases,
Air enters the ink tank from the outside air communication hole of the ink reservoir through the nozzle portion, and the ink flows down from the ink tank to the ink reservoir.

When the pressure in the ink chamber returns to a steady state by sending ink from the ink reservoir to the ink chamber, the valve closes the gap between the ink reservoir and the ink chamber. As a result, the feeding of ink from the ink reservoir to the ink chamber is stopped. Along with this, the amount of ink in the ink reservoir does not decrease, so that air does not enter the ink tank and ink does not flow from the ink tank to the ink reservoir. As described above, gas-liquid exchange can be performed between the ink tank and the ink reservoir.

In the invention of claim 3 or claim 8,
The ink container can be attached to and detached from the ink supply device.
Therefore, the ink container can be replaced as an ink cartridge. Further, in the invention of claim 4 or claim 9, the ink tank is detachable from the ink reservoir. Therefore, the ink tank can be replaced as an ink cartridge.

In the invention of claim 5 or claim 10, a valve provided in the ink chamber opens and closes between the ink chamber and the ink containing portion. Therefore, the size of the ink supply device can be reduced, and the opening / closing between the ink chamber and the ink containing portion can be reliably performed with a simple structure.

[0027]

DETAILED DESCRIPTION OF THE INVENTION An embodiment of the present invention will be described below with reference to the drawings. (First Embodiment) FIG. 1 is a front sectional view showing a bubble inkjet printer head (hereinafter, simply referred to as "printer head") 1 according to a first embodiment of the present invention. The printer head 1 includes an ink supply device 10 and a printer head chip 100. In FIG. 1, the printer head chip 100 is shown only in its outer shape.

The ink supply device 10 includes an ink container 20.
And a valve unit 50. Furthermore, the ink containing portion 20
Includes an ink tank 30 and an ink reservoir 41. The ink tank 30 is a container-like body that is sealed from the outside air, and is filled with ink inside. A cylindrical nozzle portion 31 is formed on the bottom surface side of the ink tank 30. The nozzle portion 31 is a portion that is connected to the ink reservoir 41.

The ink reservoir 41 is arranged below the ink tank 30. As shown in FIG. 1, the base body of the ink reservoir 41 has an open top surface.
A seal member 42 is provided on the upper surface. The seal member 42 prevents the ink in the ink reservoir 41 from spilling from the upper surface. Further, the outside air communication hole 42 opened is formed in a part of the seal member 42.
a is provided. As a result, the inside of the ink reservoir 41 is structured to communicate with the outside air through the outside air communication hole 42a.

Further, the central portion of the seal member 42 is opened in a circular shape, and the O-ring 43 is attached to this portion. When the tip of the nozzle part 31 of the ink tank 30 enters the O-ring 43, the nozzle part 31 and the O
The ring 43 fits together without a gap. Further, the bottom surface side of the ink reservoir 41 extends downward in a tubular shape and is connected to the valve portion 50.

The valve section 50 includes the following ink chamber 51 and valve 5.
2, a spring (biasing member) 53 and an ink delivery section 54. The ink chamber 51 is an ink container that is integrally formed with a portion that extends in a cylindrical shape from the bottom surface side of the ink reservoir 41 and has a substantially rectangular parallelepiped shape. Inside the ink chamber 51, a valve 52 and a spring 53 are arranged. Valve 52
This is for opening and closing between the valve section 50 side and the ink containing section 20 side. That is, in FIG. 1, the ink container 20
Side (portion extending from the bottom surface side of the ink reservoir 41 in a cylindrical shape)
And the valve portion 50 side (ink chamber 51) are opened. However, in the steady state, the valve 52
Is pressed against the upper surface of the ink chamber 51 (the connecting portion with the portion that extends in a cylindrical shape from the bottom surface side of the ink reservoir 41) by the urging force of the spring 53, and the valve portion 50 side and the ink containing portion 20 side are It is placed in a position that closes the space.

The valve 52 may be made of any material, but is preferably made of, for example, a rubber elastic body (elastomer) because it has a high closing property. The spring 53 is
It is a compression coil spring that is attached so as to connect the lower surface side of the valve 52 and the bottom surface of the ink chamber 51, and biases the valve 52 upward. The ink delivery section 54 is provided in the ink chamber 51.
It is a cylindrical one provided on the bottom side of the. The ink delivery unit 54 is for delivering ink to the printer head chip 100 side.

In the first embodiment, the ink tank 30 serves as an ink cartridge and is detachably attached to the printer head 1. As a structure for attaching and detaching the ink tank 30, for example, the structure shown in FIG. FIG. 2 is a diagram showing an embodiment of a valve structure provided in the nozzle portion 31, and is a diagram showing both an open state and a closed state. First,
In the closed state of the upper diagram, the valve 31c is closed by the biasing force of the coil spring 31d. And the ink tank 3
When the nozzle unit 31 of 0 is attached to the ink reservoir 41,
The rod 31e pushes up the valve 31c, so that the nozzle portion 31 of the ink tank 30 and the ink reservoir portion 41 communicate with each other.

In addition, the ink tank 30 is replaced with the ink reservoir 4
When pulling out from 1, the valve is closed by the operation opposite to the above.
1c is closed. Therefore, immediately before the ink tank 30 is mounted, the internal ink does not leak even if the tip of the nozzle portion 31 faces downward. Further, when the ink tank 30 is replaced, when the ink tank 30 is pulled out, the valve 31c is immediately closed, so that the ink does not leak from the tip of the nozzle portion 31 at this time as well.

FIG. 3 is a diagram showing an overall view (front sectional view) of the printer head 1 and a detailed view of portion A in the overall view. The printer head chip 100 includes a substrate 101.
And a film 103, a nozzle sheet 104, and the like.

The substrate 101 is made of a semiconductor substrate such as silicon and has a heating resistor (heater) 102 formed on one surface (lower surface in FIG. 3) thereof. The heating resistor 102 is for heating the ejected ink. The drive control of the heating resistor 102 is performed by the substrate 10
Done by 1. Although not shown on the substrate 101,
A logic IC, a driver transistor, etc. are provided.

The film 103 is formed on the substrate 101 in FIG.
It is laminated on the bottom surface. The film 103 is made of, for example, an exposure curing type dry film resist,
After being laminated on substantially the entire surface of the substrate 101 on which the heating resistor 102 is formed, unnecessary parts are removed by a photolithography process to form a predetermined shape. As a result, the film 103 is formed so as to surround the peripheral portion of each heating resistor 102 in a substantially concave shape. A portion surrounding the heating resistor 102 becomes an ink pressurizing chamber 105. Therefore, film 1
Reference numeral 03 forms a part of the ink pressurizing chamber 105.

The nozzle sheet 104 is a sheet-like member on which nozzles 104a for ejecting ink are formed, and is laminated on the lower layer of the sheet 103. Nozzle 10
4a is a hole opened in a circular shape, and each heating resistor 10
It is arranged so as to be located on the lower side of 2. The nozzle sheet 104 forms a part of the ink pressurizing chamber 105.

Further, an ink flow path portion 106 is formed so as to communicate with each ink pressurizing chamber 105. The ink flow path portion 106 is for feeding the ink supplied from the ink supply device 10 to each ink pressurizing chamber 105. That is, the ink flow path section 106 and the above-described ink delivery section 54 are in communication with each other. Therefore, the ink supplied from the ink supply device 10 flows into the ink flow path portion 106 and fills the ink pressurizing chamber 105.

The above ink pressurizing chamber 105 and nozzle 104
A large number of a are arranged on the substrate 101 in a substantially straight line.
Then, as shown in the overall view of FIG.
Ink i is ejected from. The heating resistor 102 selected by a command from a printer control unit (not shown)
Then, the heating resistor 102 is rapidly heated by passing a current pulse for a short time (for example, about 1 to 3 microseconds). As a result, ink bubbles are generated in the portion in contact with the heating resistor 102, and the expansion of the ink bubbles pushes away a certain volume of ink. As a result, the ink i having the same volume as the displaced ink in the portion in contact with the nozzle 104a is ejected as an ink droplet from the nozzle 104a, and is landed on the printing target such as paper.

When the ink droplets are ejected, the ink pressurizing chamber 105 ejecting the ink droplets is immediately replenished with the same amount of the ejected ink. This ink is supplied through the ink delivery unit 54 of the ink supply device 10.

Next, the supply of ink after the ink has been ejected will be described in more detail. 4 to 7 show the printer head chip 100 shown in the detailed view of FIG.
FIG. 6 is a cross-sectional view showing the state of the ink after being ejected and before the ink is supplied to the ink pressurizing chamber 105. Furthermore, each printer head chip 1
The right side of 00 also shows the state of the valve portion 50 in that state.

First, FIG. 4 shows a state at the moment when the ink i is ejected from the nozzle 104a. When the ink i is ejected due to the expansion of the ink bubbles, bubbles (ink bubbles) B corresponding to the ejected ink i are generated in the ink pressurizing chamber 105. At this point,
As shown in, the valve 52 is pressed against the upper surface of the ink chamber 51 by the urging force of the spring 53, and is arranged at a position that closes the gap between the valve portion 50 and the ink containing portion 20.

Next, as shown in FIGS. 5 and 6, the bubble B gradually contracts. Along with this contraction, a force to draw the ink into the ink pressurizing chamber 105 is generated by the capillary force. Ink is supplied into the ink pressurizing chamber 105 by the generation of the pulling force.

Here, the ink pressurizing chamber 105, the ink flow path portion 106, the ink delivery portion 54 of the valve portion 50 (the ink chamber 5
1) are communicated with each other. Therefore, the pressure of the communicating portion from the ink pressurizing chamber 105 to the ink chamber 51 of the valve portion 50 becomes lower than the pressure up to that point. For this reason, the balance up to that point is lost, and in the ink chamber 51,
A suction force for pulling in the ink is generated, and the spring 53 receives a force that is compressed against the biasing force. Therefore, the valve 52 is moved downward, and the upper surface of the ink chamber 51 is opened. As a result, ink is sent from the ink containing portion 20 side to the valve portion 50 side.

Then, as shown in FIG. 7, when the bubble B in the ink pressurizing chamber 105 disappears, the pressure of the communicating portion of the valve portion 50 from the ink chamber 51 to the ink pressurizing chamber 105 is in the original state. Then, in the ink chamber 51, the suction force for drawing the ink disappears. Therefore, the spring 53
Pushes the valve 52 upward to the upper surface of the ink chamber 51 by its urging force, and the valve 52 again pushes the valve portion 50 and the ink containing portion 2 again.
Block between 0 and 0.

Description will be returned to FIG. Ink is nozzle 104
Before being ejected from a, that is, before the bubble B is generated in the ink pressurizing chamber 105, the ink is filled in the ink reservoir 41 in FIG. Then, the inside of the ink reservoir 41 and the inside of the ink tank 30 maintain an equilibrium state, and the ink reservoir 30 moves from the ink reservoir 30 to the ink reservoir 41.
Ink does not flow down inside.

Next, when the ink is ejected from the nozzle 104a and the valve 52 is opened as described above, the ink flows down from the ink reservoir 41 into the ink chamber 51 of the valve 50. Here, the inside of the ink reservoir 41 has an outside air communication hole 42a.
Therefore, the ink flows down from the ink reservoir 41 into the ink chamber 51, and at the same time, the outside air enters the ink reservoir 41 through the outside air communication hole 42a (arrow D1 in FIG. 1).

When ink flows down from the ink reservoir 41 into the ink chamber 51, the water level of the ink in the ink reservoir 41 drops. For example, when the ink level drops to the position shown in FIG. 1, the lower end 31a of the nozzle unit 31 is exposed to the outside air. As a result, the air in the ink reservoir 41 enters the ink tank 30 from the nozzle 31 (see FIG. 1).
Middle, arrow D2). This air is sent to the upper part inside the ink tank 30. When the air enters the ink tank 30, ink corresponding to the volume of the air flows down from the ink tank 30 to the ink reservoir 41 (arrow D3 in FIG. 1). Then, when the ink is filled in the ink reservoir 41 with substantially no space and the lower end portion 31a of the nozzle portion 31 is covered again with the ink, the ink flow is stopped at this position.
As a result, the state before the ink is ejected from the nozzle 104a returns to the equilibrium state.

When ink is used and the water level of the ink in the ink reservoir 41 drops, the above operation is repeated. As a result, the ink in the ink tank 30 gradually decreases.

(Second Embodiment) FIG. 8 is a front sectional view showing a printer head 1A according to a second embodiment of the present invention. In the second embodiment, the ink storage unit 20A of the ink supply device 10A is different from that of the first embodiment. Others are the same as those in the first embodiment. In the second embodiment, the ink tank 30 and the ink reservoir 41 are integrally formed. Therefore, the O-ring 43 is not provided unlike the first embodiment.

In the second embodiment, unlike the first embodiment, the ink tank 30 is not used as an ink cartridge. When the printer head 1A of the second embodiment is applied to a printer, the ink tank 30
When the ink inside is exhausted, the ink supply device 10
Replace A as a whole (in this case, the ink supply device 1
0A must be formed so as to be attachable to and detachable from the printer head chip 100), or the printer head chip 10
The entire printer head 1A including 0 is replaced. Even if it forms in this way, the same effect as 1st Embodiment is acquired.

(Third Embodiment) FIG. 9 is a front sectional view showing a printer head 1B according to a third embodiment of the present invention. In the third embodiment, the ink container 20B of the ink supply device 10B is different from that of the first embodiment. Others are the same as those in the first embodiment. In the third embodiment, the ink reservoir 41A is provided as in the first embodiment. The O-ring 43 for attaching and detaching the ink tank 30A is attached to the ink reservoir 41A, as in the first embodiment.
Is provided.

The ink reservoir 41A is a portion (O-ring 4) into which the nozzle portion 31 of the ink tank 30A is inserted.
3 is provided only) and the other parts are sealed. Therefore, unlike the first embodiment, the ink reservoir 41A is not provided with the seal member 42 or the outside air communication hole 42a.

As in the first embodiment, the ink tank 30A is provided with a nozzle portion 31 on its bottom surface, which is a portion connected to the ink reservoir portion 41A. Furthermore, inside the ink tank 30A, the air introduction pipe 32
Is provided. The air introduction pipe 32 is connected to the ink tank 3
It is opened on the upper surface side of 0A, and this portion constitutes an outside air communication hole 32a that communicates with the outside air. A buffer portion 32b having a diameter larger than the opening diameter of the outside air communication hole 32a and the lower end portion 32c of the air introduction pipe 32 is provided near the center of the air introduction pipe 32. In the present embodiment, FIG.
As shown in, the buffer portion 32b has a substantially rhombic cross section and is capable of storing ink therein.

FIG. 9 is a diagram showing when the ink is in a balanced state. Note that FIG. 9 exemplifies a state in which there is almost no ink in the air introduction tube 32. Similar to the first embodiment, when ink is ejected on the printer head chip 100 side, the valve 52 moves downward against the urging force of the spring 53, and the ink above the ink chamber 51 moves to the valve portion 50. Run down to the side. Here, since the ink storage portion 41A and the ink tank 30A are connected, the ink storage portion 2 including the ink tank 30A and the ink storage portion 41A.
The ink in 0B flows down into the ink chamber 51 of the valve portion 50.

When the ink in the ink containing portion 20B flows down into the ink chamber 51, the amount of ink in the ink containing portion 20B decreases, but at this time, the outside air enters the ink tank 30A from the air introducing pipe 32. Ink tank 30
The air that has entered into A is sent above the ink tank 30A.

When ink is sent to the side of the valve section 50 and the printer head chip 100 and the pressure inside the valve section 50 and the printer head chip 100 returns to a steady state, the valve 52 causes the spring 5 to move.
The urging force of No. 3 pushes it up to the upper surface of the ink chamber 51, and again closes the gap between the valve unit 50 and the ink containing unit 20B. Then, in the ink containing portion 20B, as shown in FIG. 9, an equilibrium state is reached with almost no ink in the air introducing tube 32.

The third embodiment has the following effects in addition to the effects of the first embodiment. First, the air introduction pipe 32 having the outside air communication hole 32a is installed in the ink tank 3
0A, and the lower end 32c of the air introduction tube 32 is located lower than the upper surface of the ink tank 30A, the inside of the ink tank 30A is not affected even when the ink tank 30A is vibrated or tilted. It is possible to prevent the ink from leaking out.

Secondly, it is possible to prevent the ink in the ink tank 30A from leaking out even when the pressure or the temperature changes. 10 and 11 are diagrams for explaining this effect. FIG. 10 shows a state at room temperature and a normal pressure, and shows a state in which there is almost no ink in the air introduction tube 32.

In this state, when the pressure decreases or the temperature rises, the air outside the air introducing pipe 32 in the ink tank 30A (the air that is cut off from the outside air and exists above the ink tank 30A) expands. To do. Due to the expansion of the air, as shown in FIG. 11, the water level of the ink outside the air introducing pipe 32 in the ink tank 30A lowers. Then, the ink flows back to the side of the air introduction pipe 32 by this amount, but this ink flows into the buffer portion 32b of the air introduction pipe 32.
It is temporarily stored inside. Therefore, the ink tank 30A
It is possible to prevent the ink inside from leaking to the outside.

In the third embodiment, the ink tank 30
The initial state of the ink in A may be a state in which there is no ink in the air introduction tube 32, or a state in which the ink is filled. When the state in which there is no ink in the air introduction tube 32 is the initial state, the state shown in FIG.

On the other hand, when the ink tank 30A is installed in a state where the ink tank 30A including the inside of the air introducing pipe 32 is filled with ink, only the ink inside the air introducing pipe 32 is initially attached. used. This is because only the inside of the air introduction pipe 32 is communicated with the outside air through the outside air communication hole 32a. Then, when almost all the ink in the air introducing tube 32 is used, the state shown in FIG. 9 is obtained.

Here, in an initial state in which almost all of the ink tank 30A including the air introducing pipe 32 is filled with ink, the sealed air existing outside the air introducing pipe 32 in the ink tank 30A is small. It is a large amount. Therefore,
Even if the closed air expands due to the decrease in pressure or the increase in temperature, the decrease in the water level of the ink existing outside the air introduction tube 32 is also slight. Therefore, due to the decrease in pressure or the increase in temperature, the reverse flow rate of ink to the air introducing pipe 32 side is also
Only a small amount. As a result, ink does not leak from the outside air communication hole 32a.

As described above, in the third embodiment, the initial state of the ink tank 30A may be either a state in which there is no ink in the air introduction tube 32 or a state in which the air is filled, and whichever state is used. Also, it is possible to prevent the ink in the ink tank 30A from leaking to the outside due to the decrease in pressure or the increase in temperature.

(Fourth Embodiment) FIG. 12 shows a fourth embodiment of the present invention.
FIG. 3 is a front cross-sectional view showing a printer head 1C which is an embodiment. In the fourth embodiment, in the ink containing portion 20C, the ink tank 30A and the ink chamber 51 of the valve portion 50 are integrally formed. Therefore, in the fourth embodiment, unlike the third embodiment, the ink reservoir 41A and the O-ring 43 are not provided. Others are the same as in the third embodiment.

In the fourth embodiment, unlike the third embodiment, the ink tank 30A is not used as an ink cartridge. Printer Head 1C of Fourth Embodiment
When applied to a printer, the ink tank 3
When the ink in 0A is exhausted, the entire ink supply device 10C is replaced (in this case, the ink supply device 10C needs to be detachably formed with respect to the printer head chip 100), or the printer head chip. The entire printer head 1C including 100 is replaced. Even if formed in this way, the same effect as that of the third embodiment can be obtained.

[0068]

According to the invention of claim 1 or 6,
Since the porous body for holding the ink is not provided in the ink containing portion, the ink containing amount can be increased. Further, instead of using a spring or the like to reduce the pressure in the ink containing portion, gas-liquid exchange is performed between the ink containing portion and the ink chamber, and a valve opens and closes the ink containing portion and the ink chamber. Therefore, the structure can be simplified. In addition, the ink can be stably held without ink leakage.

According to the invention of claim 2, claim 4, claim 7 or claim 9, gas-liquid exchange can be performed between the ink tank and the ink reservoir.

According to the third or eighth aspect of the invention, the ink containing portion can be replaced as an ink cartridge. Further, according to the invention of claim 4 or claim 9,
The ink tank can be replaced as an ink cartridge.

According to the invention of claim 5 or claim 10,
It is possible to reduce the size of the ink supply device and
The opening and closing between the ink chamber and the ink containing portion can be reliably performed with a simple structure.

[Brief description of drawings]

FIG. 1 is a front sectional view showing a printer head according to a first embodiment of the present invention.

FIG. 2 is a diagram showing an attachment / detachment structure of an ink tank.

FIG. 3 is an overall view of a printer head (front sectional view),
It is a figure which shows the A section in the general view in detail.

FIG. 4 is a cross-sectional view showing a printer head chip,
FIG. 6 is a diagram showing a state after the ink is ejected until the ink is supplied to the ink pressurizing chamber, and also a state of the valve portion in that state.

FIG. 5 is a diagram showing a state following that of FIG. 4;

FIG. 6 is a diagram showing a state following that of FIG. 5;

FIG. 7 is a diagram showing a state following that of FIG. 6;

FIG. 8 is a front sectional view showing a printer head according to a second embodiment of the invention.

FIG. 9 is a front sectional view showing a printer head according to a third embodiment of the invention.

FIG. 10 is a diagram showing a state of ink in the ink tank, and is a diagram showing a state at normal temperature and normal pressure.

FIG. 11 is a diagram showing a state of ink in the ink tank, and is a diagram showing a state at high temperature and low pressure.

FIG. 12 is a front sectional view showing a printer head according to a fourth embodiment of the invention.

FIG. 13 is a diagram showing a first example of a conventional ink supply device.

FIG. 14 is a diagram showing a second example of a conventional ink supply device.

[Explanation of symbols]

1 bubble inkjet printer head 10 Ink supply device 20 Ink storage section 30 ink tanks 31 Nozzle part 41 Ink reservoir 42 Seal member 42a Outside air communication hole 43 O-ring 50 valve 51 ink chamber 52 valve 53 Spring (biasing member) 54 Ink delivery section 100 printer head chip 101 substrate 102 heating resistor 103 film 104 nozzle sheet 104a nozzle 105 ink pressurizing chamber 106 ink flow path section

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Takumi Namekawa             6-735 Kita-Shinagawa, Shinagawa-ku, Tokyo Soni             -Inside the corporation (72) Inventor Shinichi Horii             6-735 Kita-Shinagawa, Shinagawa-ku, Tokyo Soni             -Inside the corporation F-term (reference) 2C056 EA23 EA24 FA03 KB04 KC16                       KC22

Claims (10)

[Claims] 1. An ink chamber having an ink storage section and an ink delivery section that is arranged below the ink storage section and is connected to the ink storage section so that the ink in the ink storage section can flow down and sends out ink. And for opening and closing between the ink containing portion and the ink chamber, being urged so as to close between the ink containing portion and the ink chamber, The ink container is provided with a valve that is moved so that the ink chamber and the ink chamber communicate with each other due to a decrease in pressure in the ink chamber that occurs when ink is supplied from the ink delivery unit. When the ink amount is reduced by the ink being sent from the ink containing portion to the ink chamber, the amount corresponding to the decrease amount of the ink amount is formed. An ink supply device, characterized in that it comprises a fresh air communicating hole for taking care therein. 2. The ink supply device according to claim 1, wherein the ink containing portion includes an ink tank, a nozzle portion extending below the ink tank, and an ink reservoir into which at least a lower end portion of the nozzle portion enters. And a valve that opens and closes between the ink chamber and the ink reservoir, the outside air communication hole is formed in the ink reservoir, the pressure drop in the ink chamber When the valve is moved so that the ink reservoir portion and the ink chamber communicate with each other, the amount of ink in the ink reservoir portion decreases, so that the air flows from the outside air communication hole through the nozzle portion to the ink. The ink supply device is configured to flow into the tank and to flow down from the ink tank to the ink reservoir. 3. The ink supply device according to claim 1, wherein the ink containing portion is formed so as to be removable. 4. The ink supply device according to claim 1, wherein the ink containing portion includes an ink tank, a nozzle portion extending below the ink tank, and an ink reservoir into which at least a lower end portion of the nozzle portion enters. And a valve that opens and closes between the ink chamber and the ink reservoir, the outside air communication hole is formed in the ink reservoir, the pressure drop in the ink chamber When the valve is moved so that the ink reservoir portion and the ink chamber communicate with each other, the amount of ink in the ink reservoir portion decreases, so that the air flows from the outside air communication hole through the nozzle portion to the ink. The ink is configured to flow into the ink tank from the ink tank, and the ink tank is configured to flow from the ink tank to the ink tank. The ink supply apparatus characterized by being detachably formed. 5. Any one of claims 1 to 4
The ink supply device as described in the item 1, wherein the valve is provided in the ink chamber, and is biased toward the ink containing portion by a biasing member. 6. A printer head including an ink supply device and a printer head chip, wherein the ink supply device is disposed below the ink storage part, and the ink in the ink storage part is disposed below the ink storage part. An ink chamber that is connected to the ink containing portion so that the ink can flow down, and has an ink sending portion that sends out ink, and is for opening and closing between the ink containing portion and the ink chamber. The ink is urged to close the ink chamber, and the pressure in the ink chamber decreases when ink is supplied from the ink delivery unit of the ink chamber due to the decrease in pressure in the ink chamber and the ink chamber. A valve that is moved so as to communicate with the chamber, wherein the ink storage portion is formed so as to communicate with the outside air,
When the ink amount decreases due to the ink being sent from the ink storage section to the ink chamber, an outside air communication hole is provided for taking in air corresponding to the decrease in the ink amount. The printer head chip has a heating resistor and a plurality of ink pressurizing chambers, which communicate with the ink chamber of the ink supply device, are arranged side by side on a substrate, and the ink is generated by driving the heating resistor. A printer head for ejecting ink in a pressure chamber from a nozzle. 7. The printer head according to claim 6, wherein the ink containing portion of the ink supply device includes an ink tank, a nozzle portion extending below the ink tank, and at least a lower end portion of the nozzle portion. An ink reservoir portion into which the ink enters, the valve opens and closes between the ink chamber and the ink reservoir portion, the outside air communication hole is formed in the ink reservoir portion, the ink chamber When the valve is moved so that the ink reservoir and the ink chamber communicate with each other due to the decrease in the pressure, the amount of ink in the ink reservoir decreases, and the ink passes through the nozzle from the outside air communication hole. The ink is configured to flow down from the ink tank to the ink reservoir while air enters the ink tank. Head. 8. The printer head according to claim 6, wherein the ink containing portion of the ink supply device is detachably formed. 9. The printer head according to claim 6, wherein the ink containing portion of the ink supply device includes an ink tank, a nozzle portion extending below the ink tank, and at least a lower end portion of the nozzle portion. An ink reservoir portion into which the ink enters, the valve is for opening and closing between the ink chamber and the ink reservoir portion, the outside air communication hole is formed in the ink reservoir portion, the ink chamber When the valve is moved so that the ink reservoir and the ink chamber communicate with each other due to the decrease in pressure, the amount of ink in the ink reservoir decreases, so that the outside air communication hole passes through the nozzle portion. The air is configured to flow into the ink tank, and the ink flows down from the ink tank to the ink reservoir. Printer head is characterized in that it is detachably formed from the serial ink reservoir. 10. The printer head according to any one of claims 6 to 9, wherein the valve of the ink supply device is provided in the ink chamber, and the ink is accommodated by a biasing member. A printer head characterized in that it is biased toward the department side.