JP3513979B2 - Ink cartridge for inkjet printer - 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 cartridge suitable for an ink jet printer in which an ink jet recording head and an ink cartridge are mounted on a carriage and ink is replenished by replacing the cartridge.

[0002]

2. Description of the Related Art In an ink jet printer of a type in which an ink container is mounted on a carriage having an ink jet recording head, fluctuations in water head pressure due to rocking of ink due to movement of the carriage and printing due to foaming In order to prevent defects, the ink storage container is divided into two regions, the porous body is stored on the recording head side, and the ink is stored on the other region, as described in European Patent Publication No. 581531. Something that has been done is proposed.

With such a structure, since the ink is supplied to the recording head through the porous body, it is possible to prevent the inconvenience caused by the ink swing as much as possible. However, since the recording head and the porous body are joined by pressing the projection communicating with the recording head into the through hole formed in the side portion of the container, the piezoelectric vibrator serves as an actuator for ejecting ink. There is a problem that it cannot be applied to a recording head such as the ink jet recording head used, which does not like to mix air bubbles into the pressure generating chamber.

[0004]

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object of the present invention is to flow ink in an ink chamber to a foam chamber without interruption.
Supply it to the print head while maintaining the negative pressure of the ink.
It is to provide an ink cartridge that can .

[0006]

SUMMARY OF THE INVENTION In the invention of claim 1 in order to solve such a problem, the absorption and the ink chamber for storing ink, the ink as well as connected through a communication hole into the ink chamber And a foam chamber for accommodating the porous body, and has a step under the communication hole,
A groove connecting the ink chamber and the foam chamber is formed below
The foam chamber and ink chamber are in a depressurized state.
Is held in the foam chamber and ink chamber
The porous body in which the ink of and is always in elastic contact with the communication hole
Is maintained at a constant pressure difference determined by the surface tension of
The pressure difference is maintained by the consumption of ink in the porous body.
At the point where the
Ink is supplied from the ink chamber to the porous body to print.
It is configured to supply ink to the head. Again
In the invention of claim 2, an ink chamber for storing ink,
The ink chamber is connected to the ink chamber through a communication hole, and
A foam chamber containing a porous body that absorbs ink.
In addition, below the communication hole, a step where the ink chamber side becomes higher
There is a difference between the foam chamber and the ink chamber
While being kept under reduced pressure,
The ink in the ink chamber always makes elastic contact with the communication hole.
Maintain a constant pressure difference determined by the surface tension of the porous body
And the pressure difference due to the consumption of ink in the porous body.
When the pressure is no longer maintained, the constant pressure difference
Ink from the ink chamber to the porous body until
To supply ink from the ink supply port to the recording head.
Is configured.

[0007]

[Function] A constant negative pressure is applied to the ink in the ink chamber by the porous body.
The ink can be supplied to the recording head while maintaining
According to the invention, the porous body is formed without wasting ink in the ink chamber.
According to the invention of claim 2, the carriage can be supplied to
Make sure to write the ink in the ink chamber regardless of the inclination of
Can be supplied to the recording head.

[0008]

Embodiments of the present invention will be described below in detail with reference to the illustrated embodiments. 1 (a) and 1 (b) show an embodiment of the present invention, in which reference numeral 1 is a main body container, and as shown in FIG. A foam chamber 11 which is divided into four, five and six, and each of the chambers 4, 5, and 6 accommodates a porous body 20 suitable for absorbing ink by partition walls 10, 10 and 10, respectively, and an ink. Is separated into an ink chamber 12 that accommodates.

The volume of the porous body 20 is selected to be larger than that of the foam chamber 11, and the porous body 20 is compressed and accommodated in the foam chamber 11.

The amount of ink contained in the foam chamber 11 and the ink chamber 12 is 20 to 30 on the side of the foam chamber 11.
The volume ratio is selected so as to increase by about%.

As described above, by setting the ink amount on the side of the foam chamber 11 to be larger than the ink amount on the ink chamber 12, when three color inks are provided by one cartridge, the consumption amount of each color ink is reduced. It is possible to make it difficult to visually recognize variations in the liquid level in the ink chamber due to the balance, and to eliminate unnecessary concerns from the consumer regarding the remaining amount of ink. Also, when the cartridge is discarded, the ink becomes a porous material. Since it is absorbed, it can be prevented from flowing out and the environment can be protected.

At the lower end of each foam chamber 11, there are provided ink supply ports 13, 13 for engaging with ink supply needles 50 of the recording head.
13 is provided, and the upper end of the container body 1 is a foam chamber 1
1 is sealed by a lid 16 having a pair of ink injection ports 14 and 15 at positions facing each other.

Protrusions 16a and 16b are formed in the region of the back surface of the lid 16 located in the foam chamber 11 so as to surround the ink injection ports 14 and 15.
The porous body 20 is pressed against the bottom surface where the ink supply port 13 is formed by 6a and 16b.

Of these protrusions 16a and 16b,
The protrusion 16a facing the ink supply port 13 is formed to be longer than the protrusion 16b farther from the ink supply port 13, and the vicinity of the ink supply port 13 is compressed with the highest pressure. It is like this.

At the bottom of each foam chamber 11, the porous body 2 is provided.
A protrusion 22 for compressing 0 in cooperation with the lid 16 is formed, and a recess 23 that forms a vacant chamber having a constant opening area at its upper end and one end communicates with this, and the other end A through hole 24 communicating with a packing described below is provided, and a filter 25 is fixed to the upper end of the recess 23.

Reference numeral 30 denotes a packing member, which is the ink supply port 1
It is formed of an elastic material such as rubber provided at the lower end of 3 and is configured as a funnel-shaped packing that expands upward. The lower end has a thicker tubular portion 31 than other portions.
The upper end 33 of the peripheral edge of the taper portion 32 abuts the step portion 13a of the ink supply port 13, and the boundary with the taper portion 32 is formed as a thin connecting portion 34.

As a result, the cylindrical portion 31 is securely held in the ink supply port 13, and the upper edge 33 of the peripheral edge is the stepped portion 13.
Since it is prevented from moving upward by a, it is firmly fixed to the ink supply port 13 when the ink supply needle is attached and detached. Further, the taper portion 32 for ensuring the airtightness with the ink supply needle is provided with the thin connection portion 34 to connect the ink
Since it is fixed to No. 3, it can be moved to some extent without being deformed. Therefore, it is possible to secure the airtightness with the ink supply needle while absorbing the relative displacement of the ink supply needle 50. You can

The partition 10 that divides the foam chamber 11 and the ink chamber 12 forms a continuous long hole from the bottom surface of the container 1 up to a certain height to form a communication hole 19 for gas-liquid separation.
Is provided, a part of which is in contact with the communication hole 19, and the porous body 20 is accommodated in the foam chamber 11 in a state where the communication hole 19 is pressed to some extent.

On the other hand, the black ink cartridge, which is manufactured to be relatively smaller than the color ink cartridge, but has a volume larger than that of the colored ink, is the ink chamber 12 and the foam chamber as shown in FIG. 1
A partition 17 that extends from the bottom surface to the vicinity of the upper portion is formed between the partition 10 that divides the ink chamber 11 and the side wall 1a of the container body 1 to divide the ink chamber 11 into two chambers 12a and 12b, and the ink described below. It is configured to prevent the leakage of ink by preventing the negative pressure at the time of injection and the deformation of the entire container due to the external pressure at the time of use. Although the divided chambers 12a and 12b are connected to each other in the foam chamber 11 through the communication hole 19 of the partition 10, the communication hole may be provided below the partition wall 17.

When mounted on the carriage, a plurality of ribs 18, 18 extending vertically are formed on the inner surface of the wall, which is a side wall 1a in this embodiment, which is easy to see from the outside. It is configured to promptly drop and increase the contrast to easily detect the remaining amount of ink. Incidentally, reference numeral 19 in the drawing
Reference character a denotes a groove portion, which will be described later, formed on the surface of the partition 10 on the side of the foam chamber 11.

FIG. 4 shows an embodiment of the lid 16 described above. In the figure, reference numerals 14 and 15 are holes for injecting ink.
It is formed in the region where the porous body is accommodated, and the ink injection hole 14 is connected to the atmosphere communication ports 41, 41, 41 via the meandering grooves 40, 40, 40.

These grooves 40, 40, 40 are provided for the ink injection hole 1 when the ink injection work described later is completed.
A capillary tube is formed when the seals 42 and 15 and the seal 42 covering the atmosphere communication port 41 are attached. The seal 42 is provided with a tongue piece 45, a part of which protrudes from the lid body 16 via a constricted portion 43 provided on the way to the atmosphere communication port 41. With this configuration, when the tongue piece 45 is peeled off from the lid body 16, only the tongue piece 45 can be easily separated from the constricted portion 43, and only the atmosphere communication port 41 can be exposed.

The seal 42 has a pattern of characters and illustrations printed on the surface of a main body 44 that constantly seals the grooves 40, 40, 40, and a tongue that connects to the main body 44 via a constricted portion 43. The pieces 45 are printed with different colors and patterns.

For example, while the main body 44 has a blue background color and black characters and illustrations are printed, the tongue 45 has a contrast with the main body 44 background color such as yellow and red. The high color is a flesh color, and characters and illustrations of colors mainly in black and blue are printed. In this way, the colors of the main body 44 and the tongue piece 45 and the pattern are clearly different from each other, so that the tongue piece 4 is not
It is possible to call off the peeling of 5.

In the cartridge thus constructed, the ink supply port is sealed by the film 46, and the injection needles are hermetically inserted into the ink injection ports 14 and 15,
One of the injection needles is closed by the exhaust means and the other injection needle is closed.

When the exhaust means is operated in this state, the pressure in the foam chamber 11 and the ink chamber 12 is reduced. When the evacuation operation is stopped at the stage where the pressure is reduced to a predetermined pressure and the other injection needle is made to communicate with the measuring tube, the ink contained in the measuring tube is once absorbed by the porous body 20, and then the communicating hole 1
It flows into the ink chamber 12 via 9.

At the stage where the amount of ink regulated by the measuring tube has flowed in, a seal 42 is attached to the surface of the lid 16 to seal the inlets 14, 15 and the meandering groove 40, and the communicating port 41 under reduced pressure. By stopping, the foam chamber 11 and the ink chamber 12 are maintained in a reduced pressure state.

When the cartridge thus constructed is used, when the tongue piece 45 of the lid 16 is peeled off, the tongue piece 45 is separated from the main body 44 with the constricted portion 43 as a boundary.
As a result, the ink injection port 14 communicates with the atmosphere communication port 41 via the groove 40. In use, the foam chambers 4, 5 and 6 communicate with the atmosphere through the long groove 40 that meanders. Therefore, it is possible to prevent the evaporation of ink while ensuring the air permeability.

In this state, when the ink supply port 13 of the ink cartridge is aligned with the ink supply needle 50 of the recording head and pushed in, as shown in FIG. It penetrates the seal 46 and comes into contact with the hole of the packing member 30. The packing member 30 is
Since it expands upward, the packing member 30 is elastically deformed by being elastically pressed by the taper portion 51 of the ink supply needle 50.
Penetrate through.

When such an ink supply needle 50 is used in such a manner that it is inserted into the packing member 30, even if there is a slight horizontal displacement between the ink supply needle of the recording head and the center of the packing. As long as the tip of the ink supply needle is engaged with the hole of the packing member 30, the taper portion 32 follows the ink supply needle 50 due to the elasticity of the connection portion 34, so that the ink supply port 13 and the ink supply needle 50 are connected to each other. It can be surely sealed.

Then, a negative pressure is exerted on the recording head to force the ink to flow from the cartridge into the recording head, such as when the recording head is filled with ink immediately after the ink cartridge is mounted or when the ink ejection capability is recovered. In this case, since a large negative pressure acts on the cartridge side, the packing member 3 that separates the cartridge from the atmosphere.
The 0 taper portion 32 is deformed toward the ink cartridge.

As a result, the taper portion 3 of the packing member 30.
2 is elastically pressed by the ink supply needle 50 due to the pressure difference, so that a higher sealing property is exhibited.

Further, as shown in FIG. 5B, the taper portion 51 of the ink supply needle 50 is not pushed in until the ink supply needle 50 penetrates the taper portion 32 of the packing member 30.
As long as it is elastically contacted with, the downward elastic force is accumulated in the tapered portion 32, so that the airtightness with the ink supply needle 50 can be secured.

According to such a mode of use, since the tip of the ink supply needle 50 is directly sealed, the dead space is extremely small, and it is possible to prevent the injection of air due to the piston effect due to pushing.

When a negative pressure is applied from the nozzle opening side of the recording head in this state, the ink absorbed in the porous body 20 is recorded from the through hole 24 through the through holes 51, 51 of the ink supply needle. Pour into the head.

A predetermined amount of ink is consumed and the porous body 2
When the ink amount of 0 becomes small and the liquid level decreases, the pressure of the ink chamber 12 overcomes the ink holding force of the porous body 20 in the vicinity of the communication hole 19 and bubbles enter the ink chamber 12 from the communication hole 19. . As a result, the pressure in the ink chamber 12 rises and the ink flows into the foam chamber 11.

The ink flowing into the foam chamber 11 is absorbed by the porous body 20 to slightly raise the ink level in the foam chamber 11, and the ink holding force of the porous body 20 and the pressure of the ink chamber 12 in the vicinity of the communication hole 19 are increased. When and are in equilibrium,
The flow of ink from the ink chamber 12 to the foam chamber 11 stops.

FIG. 6 shows this process.
Indicates the head pressure of the porous body 20 in the foam chamber 11, and the symbol G indicates the amount of ink in the ink chamber 12. As is apparent from this figure, the ink initially filled in the porous body 20 is constant. When the water head pressure of the porous body 20 is reduced to a predetermined value and the pressure of the ink chamber 12 is reduced to such an extent as to overcome the ink holding force of the porous body 20 in the vicinity of the communicating hole 19, the amount of w1 is consumed up to the amount w1. The ink gradually flows from the ink chamber 12 into the foam chamber 11 step by step until the ink holding force of the porous body 20 restores the balance with the pressure of the ink chamber 12.

As a result, although the ink amount in the ink chamber 12 gradually decreases, the head pressure of the porous body 20 is maintained substantially constant, and the ink can be supplied to the recording head with a constant pressure difference. Become.

When the recording head consumes the ink up to the predetermined amount w2, the ink in the ink chamber 12 is exhausted, but the porous body 20 is still intermittently supplied with the ink from the ink chamber 12 to the foam chamber 11. There is ink equivalent to that in.

Therefore, further printing can be performed with the amount of ink absorbed in the porous body 20. When the specified amount w3 of ink is consumed, it becomes impossible to supply the ink from the porous body 20.

Since a constant amount of ΔT can be supplied to the recording head from the time when all the ink in the ink chamber 12 is absorbed by the porous body 20 to the time when printing is disabled, the ink in the ink chamber 12 can be supplied. The presence or absence of the ink indicates the near end of the ink of the entire cartridge, and if a new cartridge is prepared at this stage, the ink can be quickly replenished.

By the way, as described above, the ink cartridge of the present invention is required to maintain a negative pressure inside during printing. Therefore, in addition to ensuring the airtightness of the ink supply port and the ink supply needle, the ink chamber 12 The ink supply process from the ink to the foam chamber 11 is a very important factor. Therefore, next, a structure for managing the supply of ink from the ink chamber 12 to the foam chamber 11 will be described.

In the embodiment shown in FIG. 7, the stepped portion 6 is formed at the boundary between the foam chamber 11 and the ink chamber 12 so that the ink chamber side becomes higher.
The groove 6 which forms 0 and connects both chambers to the lower part
1 is formed.

According to this embodiment, the porous body 20 in contact with the communication hole 19 is reliably received by the step portion 60, the compressibility in the vicinity thereof is increased, and the ink chamber 12 through the communication hole 19 is increased.
Not only can the pressure difference between the foam chamber 11 and the foam chamber 11 be reliably ensured, but also when the ink in the ink chamber 12 is low, the ink in the ink chamber 12 is collected by the groove 61, and this is collected. Therefore, the ink in the ink chamber can be supplied to the recording head without waste.

In the embodiment shown in FIG. 8, the bottom surface of the ink chamber 12 is made higher than the foam chamber 11 side to form a step 62, and the step 62 receives the lower portion of the porous body 20 and the vicinity of the communication hole 19. In addition to increasing the compressibility of the porous body 20, the slope 63 from the ink chamber 12 toward the foam chamber 11 is added as necessary.

According to this embodiment, it becomes possible to collect the ink in the ink chamber 11 by displacing it in the communication hole 19.
As a result, the ink chamber 1 is not affected by the inclination of the carriage.
The two inks can be reliably supplied to the recording head.

In the embodiment shown in FIG. 9, the thin groove portion 19a (see FIG. 9) is formed on the foam chamber side so as to communicate with the upper portion of the communication hole 19 of the partition which divides the foam chamber 11 and the ink chamber 12. 2 (see FIG. 3),
Further, in order to secure an air passage from the ink chamber 12 to the foam chamber 11, a penetrating portion 19b is formed at the lower end of the groove portion 19a.

According to this embodiment, the upper portion of the porous body 20 is connected to the communicating hole 19 through the space formed by the narrow groove portion 19a.
Will be connected to.

As a result, the communicating hole 1 is formed through the narrow groove portion 19a and the region of the upper portion of the porous body 20 where the capillary force is relatively small.
Since 9 is connected, the ink can be smoothly replaced with air, and the ink in the ink chamber 12 can be surely allowed to flow into the foam chamber 11 to prevent an ink supply error.

FIG. 10 shows another embodiment of the present invention, in which reference numeral 65 is a horseshoe-shaped projection provided at the bottom of the foam chamber 12, and a space is provided in the vicinity of the communication hole 19. This is to ensure that the ink in the ink chamber 12 can easily flow into the foam chamber 11.

In the above embodiment, the foam chamber 11 and the ink chamber 12 are partitioned by the single partition 10, but in the case of a single color ink cartridge, it is shown in FIG. ), As shown in FIG. 11B, an ink chamber 71 is formed so as to surround two or three sides of the foam chamber 70.
By forming the communication hole 73 in at least one of the walls 72, 72, 72 for partitioning 1, the ink cartridge can store a large amount of ink as compared with the volume of the entire ink cartridge, and the presence or absence of ink. Can be checked from a wide angle. Incidentally, reference numeral 74 in the figure indicates an ink supply port.

[0053]

[Brief description of drawings]

FIG. 1A and FIG. 1B are cross-sectional views showing an embodiment in which the present invention is applied to a color ink cartridge.

FIG. 2 is a perspective view showing an embodiment of the ink container body of the same ink cartridge.

FIG. 3 is a perspective view showing an embodiment of an ink container body of a black ink cartridge.

FIG. 4 is a top view showing the structure of the lid on the foam chamber side. FIG. 4 (a) shows a state where the seal is not attached, and FIG. 4 (b) shows a state where the seal is attached.

5 (a) and 5 (b) are diagrams showing a state in which an ink cartridge of the same as above is mounted on a recording head.

FIG. 6 is a diagram showing a relationship between an ink consumption amount, a head pressure, and an ink amount in an ink chamber.

FIG. 7 is a diagram of an example showing a structure of a boundary region between a foam chamber and an ink chamber.

FIG. 8 is a diagram showing another example of the structure of the boundary region between the foam chamber and the ink chamber.

9 (a) and 9 (b) are views showing a vertical cross section and a cross sectional structure taken along line AA of another embodiment of the structure near the boundary between the foam chamber and the ink chamber, respectively.

10A and 10B are a longitudinal sectional view and a lateral sectional view, respectively, showing another embodiment of the structure near the boundary between the foam chamber and the ink chamber.

11A and 11B are cross-sectional views showing another embodiment of the ink cartridge, respectively.

[Explanation of symbols]

1 Cartridge body Two or three partition boards 10 Partitions 11 foam room 12 ink chamber 13 Ink supply port 14, 15 Ink injection holes 16 Lid 17 partitions 18 ribs 19 communication holes 19a groove 20 Porous body 22 Convex portion for compressing porous body 23 recess 24 through holes 25 filters 30 packing 31 tubular part 32 taper 40 grooves 41 Air communication port 42 seal

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Takao Kobayashi 3-3-5 Yamato, Suwa-shi, Nagano Seiko Epson Co., Ltd. (72) Inventor Takashi Koike 3-3-5 Yamato, Suwa-shi, Nagano Sei Co-Epson Co., Ltd. (72) Inventor Koji Suda 3-5 Yamato, Suwa-shi, Nagano Seiko Epson Co., Ltd. (56) Reference JP-A-6-40043 (JP, A) JP-A-5- 270001 (JP, A) JP-A-4-144755 (JP, A) JP-A-63-87242 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) B41J 2/175

Claims (2)

(57) [Claims] 1. An ink chamber for accommodating ink, a foam chamber connected to the ink chamber through a communication hole and accommodating a porous body for absorbing the ink, and a step at a lower portion of the communication hole. And a groove connecting the ink chamber and the foam chamber is formed thereunder, and the foam chamber and the ink chamber are held in a reduced pressure state, and the ink of the foam chamber and the ink chamber is Is always maintained at a constant pressure difference determined by the surface tension of the porous body elastically contacting the communication hole, and at the time when the pressure difference is no longer maintained due to ink consumption of the porous body,
An ink cartridge for an inkjet printer, which supplies ink to the porous body from the ink chamber and supplies the ink to a recording head until the constant pressure difference occurs. 2. An ink chamber for accommodating ink, and a foam chamber connected to the ink chamber through a communication hole and accommodating a porous body for absorbing the ink are provided below the communication hole. A step is formed on the ink chamber side so that the foam chamber and the ink chamber are kept in a depressurized state, and the ink in the foam chamber and the ink chamber is always in elastic contact with the communication hole. The pressure difference is maintained at a constant pressure difference determined by the surface tension of the body, and when the pressure difference is no longer maintained due to the consumption of ink in the porous body, the porous medium is removed from the ink chamber until the constant pressure difference occurs. An ink cartridge for an inkjet printer that supplies ink to the body and supplies the ink from the ink supply port to the recording head.