GB2293141A - Multi-chambered ink cartridge for ink jet printer. - Google Patents

Description

I- INK TANY, CARTRIDGE FOR A PRINTER OR THE LIKE 2293141 The present

invention relates generally to an ink-supplied printer being supplied with ink from an ink supply tank and more particularly to an ink supply tank which allows for the continuous supply of ink to the printer head while avoiding adverse effects from temperature, atmospheric changes or vibrations. The present invention may allow for a larger volume of ink in the ink supply tank and for a greater percentage of the ink in the tank to be transferred to the printer head. Also, the present invention comprises a tank with transparent sides so the user is able to easily determine the remaining quantity of ink, and also means for dampening of the unwanted movement of ink within the ink supply tank.

This invention also relates to an ink cartridge for an inkjet printer in which an ink jet recording head, and an ink cartridge are mounted on a movable carriage, and in particular an ink jet cartridge which, upon depletion of the ink from the old cartridge, is replaced with a new ink cartridge.

A prior art ink jet printer in which an ink containing unit and an ink jet recording head are mounted on a carriage is disclosed in European Patent Publication No. 581,531. In the disclosed printer, in order to prevent printing failures caused by variation of the ink level or air bubbles due to movement of the ink cartridge, which is caused by the movement of the carriage, the ink container is divided into two regions. A first region of the container adjacent the recording head houses ink impregnated in a porous member, and a second region contains liquid ink without a porous member. This structure enables the ink to be conducted to the recording head via the porous member so that the problems arising from movement of the ink in the cartridge are prevented from occurring to a certain extent.

The porous member is held in fluid communication with the recording head by a projecting member which is inserted through a hole formed in the side portion of the container. However, such a structure cannot be applied to a recording head in which air 2 bubbles must be stopped from entering a pressure chamber, such as that for an ink jet printer in which a piezo-electric vibrator is used as an actuator for ink ejection.

Accordingly, an inkjet printer which solves the above-mentioned problems is derived.

Accordingly, it is an object of the invention to provide an improved ink cartridge for an inkjet printer.

It is an object of the present invention to provide a high-quality and highly reliable ink-supplied printer of a simple construction which is capable of supplying a stable and appropriate quantity of ink from an ink tank to a printer head and is less subject to the influence of environmental changes such as temperature or atmospheric variations.

It is a further object of the invention to provide a cartridge for an inkjet printer which can be mounted using minimal force and with a large tolerance for misalignment of the ink supply needle, which can cooperate with a recording head to attain a sufficient hermetic seal, while producing a dead space as small as possible.

Yet another object of the invention is to prevent air bubbles from entering the recording head while maintaining a negative pressure in the chamber containing the porous member.

Still other objects, features and advantages of the present invention will become more apparent from the following description when taken in conjunction with the accompanying drawings in which preferred embodiments of the present invention are shown by way of illustrative example and not in a limiting sense. In accordance with a first aspect of the present invention there is provided an ink tank cartridge for an ink-jet type recording apparatus, comprising: a plurality of first chambers; a plurality of second chambers, each second chamber being adjacent to and associated with a first chamber; a plurality of partition walls disposed in said cartridge, each said partition being formed with a communicating hole formed therein disposed between said associated

3 chambers, said communicating hole being positioned in the vicinity of the bottom of said partition wall and extending only a portion of the width of said partition wall as viewed in the direction of said bottom of said partition wall; and a plurality of ink supply ports, each extending through a wall of a respective one of said plurality of second chambers, said plurality of ink supply ports supplying ink to the exterior of said cartridge, all of said first chambers and associated second chambers being formed as an integral unit.

According to a second aspect of the present invention, there is provided an ink-get type recording apparatus for outputting ink onto a recording medium, comprising:

a recording head for ejecting ink; and a multi-colour ink tank cartridge removably mountable onto said recording head of said ink-jet type recording apparatus for delivery of ink thereto, said ink tank cartridge, including:

a plurality of first chambers; a plurality of second chambers, each second chamber being adjacent to and associated with a first chamber; a plurality of partition walls disposed in said cartridge, each said partition being formed with a communicating hole formed therein disposed between said associated chambers, said communicating hole being positioned in the vicinity of the bottom of said partition wall and extending only a portion of the width of said partition wall as viewed in the direction of said bottom of said partition wall; and a plurality of ink supply ports, each extending through a wall of a respective one of said plurality of second chambers, said plurality of ink supply ports supplying ink to the exterior of said cartridge, all of said first chambers and associated second chambers being formed as an integral unit.

According to a third aspect of the present invention, there is provided a system for supplying ink to an ink-jet type recording apparatus and outputting ink onto a recording medium, said system comprising:

IM a recording head for ejecting ink; and 4 a multi-colour ink tank cartridge removably mountable onto said recording head of said ink-jet type recording apparatus for delivery of ink thereto, said ink tank cartridge including:

a plurality of first chambers; a plurality of second chambers, each second chamber being adjacent to and associated with a first chamber; a plurality of partition walls disposed in said cartridge, each said partition being formed with a communicating hole formed therein disposed between said associated chambers, said (-ammunicating hole being positioned in the vicinity of the bottom of said partition wall and extending only a portion of the width of said partition wall as viewed in the direction of said bottom of said partition wall; and a plurality of ink supply ports, each extending through a wall of a respective one of said plurality of second chambers, said plurality of ink supply ports supplying ink to the exterior of said cartridge, all of said first chambers and associated second chambers being formed as an integral unit.

According to a forth aspect of,the present invention, there is provided a method for providing ink to an ink-jet type recording head, comprising the steps of:

providing an ink tank cartridge having a plurality of first chambers adapted to store ink and a plurality of second chambers adapted to receive a respective porous member impregnated with ink, each of said first and second chambers being separated from each other by a partition wall; communicating ink between said associated first and second chambers through a C communicating hole adjacent to the bottom of said partition and extending only a portion e) of the width of said partition wall as viewed in the direction of said bottom of said partition wall, withdrawing ink from each porous member in each second chamber through an ink supply port extending through a wall of each second chamber; and providing ambient air to each second chamber at a location spaced from said ink supply port.

According to a fifth aspect of the present invention, there is provided an ink tank for supplying ink, the ink tank having a first chamber and a second chamber separated by a partition wall having a hole formed therein for allowing ink to pass between the chambers, wherein the communicating hole is positioned generally at the lower end of the partition wall in normal use, andlor the hole extends only along a part of the width of the partition wall.

Generally speaking, there is provided an ink-supplied printer. ink is supplied to a printer head by an ink supply system, including an ink tank having an ink supply port and a pair of side walls. An ink absorbing member is contained therein adjacent the ink supply port which occupies less than the total volume of the ink tank.

The walls of the ink supply tank may be transparent so the user can more easily determine the amount of ink remaining in the ink supply tank.

An ink receiving and transferring member terminating in an ink port may extend into the ink tank, in which case the ink absorbing member abuts and is locally compressed by the ink receiving and transmitting member. The ink receiving and transmitting member has a capillary,ink path communicating with the printer head and is supplied with ink from the ink absorbing member.

More specifically an ink cartridge may be formed of an ink chamber for storing ink and a foam chamber for receiving a porous member for absorbing ink. A partition separates the ink chamber from the foam chamber and has a hole therein so that the foam chamber is in fluid communication with the ink chamber. The ink cartridge is also formed with an ink supply port. A funnel shaped packing member is disposed within the c supply port and supplies ink to a recording head by generation of a pressure difference through the porous member. The packing member is disposed facing upward in the ink supply port. The packing member is resilient.

When an ink supply needle of the recording head is inserted into the ink supply port, the tip of the needle may resiliently contact the packing member. Since the packing member has a funnel-like shape which opens upward, the packing member is 0 6 easily deformed so as to follow the ink supply needle. Furthermore, the packing member is caused to closely contact with the needle by its resiliency. Therefore, a relative misalignment between the ink supply needle and the ink supply port can be accommodated so that the ink supply port is securely sealed.

The invention accordingly comprises the several steps and relation of one or more of such steps with respect to each of the others, and the apparatus embodying features of construction, combinations of elements and arrangement of parts which are adopted to effect such steps, all as exemplified in the following detailed disclosure, and the scope of the invention will be indicated in the claims.

For a better understanding of the invention, embodiments will now be described by way of example with reference to the accompanying drawings, in which:- Figure I is a schematic view showing an ink supply system of an ink-jet type recording apparatus according to one embodiment of the present invention; Figure 2 is a cross-sectional view of a multi-colour ink jet printer cartridge constructed in accordance with a first embodiment of the invention; Figure 3 is a cross-sectional yiew of the first embodiment rotated 900 from the view in Figure 2; Figure 4 is a perspective view showing the ink cartridge of Figures 2 and 3 with b the lid removed; Figure 5 is a perspective view showing a single colour ink cartridge constructed in accordance with a second embodiment of the invention; Figure 6(a) is a top plan view of the lid of Figure 2; Figure 6(b) is a top plan view showing the lid with a seal affixed thereto; Figure 7(a) is a cross-sectional view showing a packing member with an ink supply needle inserted therein; Figure 7(b) is a cross-sectional view of the packing member prior to insertion; Figure 8 is a graph showing the relationships of the ink consumption, the pressure level, and the amount of ink remaining in an ink chamber; 7 Figure 9 is a partial cross-sectional view of the ink cartridge showing the boundary between ink and foam chambers in accordance with a third embodiment of the invention; Figure 10 is a partial cross-sectional view of the ink cartridge showing the boundary between ink and foam chambers in accordance with a fourth embodiment of the invention; Figure 11 is a partial cross-sectional view of the boundary between ink and foam chambers of an ink cartridge constructed in accordance with a fifth embodiment of the invention; Figure 12 is a cross-sectional view taken along line 33-33 of Figure 11; Figure 13 is a partial cross-sectional view showing the boundary between ink and foam chambers of an ink cartridge constructed in accordance with a sixth embodiment of the invention; Figure 14 is a cross-sectional view taken along line 35-35 of Figure 13; Figure 15 is a cross-sectional view showing an ink cartridge constructed in accordance with a seventh embodiment of the invention; Figure 16 is a cross-sectional view showing an ink cartridge constructed in accordance with a eighth embodiment of the invention; Figure 17 is a cross-sectional view showing an ink cartridge for an inkjet printer constructed in accordance with a ninth embodiment of the invention; and Figure 18 is a cross-sectional view of the ninth embodiment of the invention rotated 900 from Figure 17.

An embodiment of the printer head according to the present invention may be used in a four-colour printer plotter or colour image printer and has four-colour ink systems and ink jets corresponding respectively to four ink colours. The four-colour printer plotter employs black, red, green and blue inks, and moves the head or a sheet of print paper or both and then ejects ink as in a conventional inkjet print head, corresponding to a desired one of the colours against the print paper at a prescribed position thereon to form an ink dot. Desired characters and figures can thus be recorded 8 by repeating the above cycle. The present invention is applicable to ink jet printers of all varieties, including print heads using heat from heated resistors or the like or the displacement of piezo-electric members or with transducers to project a drop of ink from a chamber upon application of a print signal. The ink supply tanks according to the invention may supply ink continuously to said chambers through capillary paths.

In a colour image printer using inks of four colours, that is, black, red, green and blue, a sheet of print paper is scanned by a printer head in a direction perpendicular to the direction of feed of the print paper to form one-dot line in one scanning stroke, and the print paper is fed along by line pitches to record images. In seven-colour printers, inks of four colours, that is, black, yellow, magenta and cyan, are used, and the colours of red, green and blue are formed on a sheet of print paper by superimposing inks of two 0 out of the three desired colours other than black, thereby recording colour images of seven colours.

The present invention is concerned primarily with the printer head, and more particularly, but not exclusively, with the ink tanks, and detailed description of the overall printer construction will be given only by way of a single example.

Figure 1 is a schematic view showing an ink supply system of an ink-jet type recording apparatus according to one embodiment of the present invention.

A print head unit 1 of an ink-jet type is connected to an ink tank 3 through a connecting member 2. Ink is supplied from the ink tank 3 to the print head unit 1 through a hollow needle 2a and an ink supply passage 2b of the connecting member 2, so that the print head unit 2 emits ink droplets in accordance with print signals.

The apparatus shown in Figure 1 also includes a cap member 4 disposed at nonprinting area, which cap member comes into abutment against the nozzle plate of the print head unit 1 by a drive mechanism (not shown) for preventing the nozzle openings from drying. The cap member 4 is connected through a tube 8 to a suction pump 5 which is operated by a control device 6 to suck ink from the print head unit 1 through the cap member 4. The apparatus shown in Figure 1 is also provided with an effluent tank 7 connected to an outlet port of the suction pump 5 through a tube 9.

0 9 The recording head may be of any structure such as described in European Patent Publication Nos. 581,531, 609,863, 584,823 and so on.

The ink cartridge is configured so as to be mounted with a small force and to accommodate a misalignment of a certain degree. Reference is first made to Figures 2 and 3 which depict an ink cartridge constructed in accordance with a first embodiment of the invention. A main container 501 is divided into three compartments 504, 505 and 506 by partitions 502 and 503 as shown in Figure 3. Each of the three compartments 504, 505 and 506 is divided by a centre partition wall 5 10 into foam chambers 511, 511' or 511" housing a respective porous member 520, 520' or 520 and ink chambers 512, 512' or 5 12" which are adapted to contain liquid ink. Foam chambers 511, 51P, 511 are dimensioned to receive a respective porous member 520, 520', 520".

The volume of each of porous members 520, 520' and 52W is selected so as to be larger than the capacity of each of the respective foam chambers 5 11, 5 11' or 5 11 " so as to be compressed while being retained in the respective foam chamber in a preferred embodiment. The ratio of the capacities of each foam chamber 511, 511 or 511 " and each ink chamber 512, 512' or 512" is selected so that each foam chamber 511, 511' or 511 " is dimensioned to hold 20 to 30% more ink than the respective ink chamber 5 12, 512' or 5 12" When inks of three colours are contained within a single cartridge as in Figures -2 to 4, it may be difficult to see if different amounts of ink remain in the chambers, which may be caused by unbalanced consumption of the different colour inks. When ink of one colour is depleted, and the user wishes to dispose of the cartridge, the user need not unnecessarily worry about any remaining ink of the other colours in the cartridge leaking. When a cartridge is disposed of, ink is prevented from flowing out of the C cartridge because ink of each colour is absorbed by each respective porous member, thereby protecting the environment from any leakage of ink.

0 Ink supply ports 513, 513' and 51Y of each chamber (only one of the ports is shown in the drawings, chamber 511 being exemplary of each chamber 511, 511' and 511 ") are formed in main container 501 within a respective foam chamber 511, 511' and 9 11 ". Each ink supply port 5 13, 5 13' and 5 13 " is adapted to engage with a respective ink supply needle (not shown) of the recording head which are inserted at the lower end of each of the foam chambers 5 11, 5 11' and 5 11 ".

Referring now to Figures 2 and 3, the upper end of the main container 501 is sealed by a lid 516. Two ink filling ports 514 and 515 are formed at positions on lid 516 corresponding to foam chamber 511. Similarly, as shown in Figure 6(a), each chamber 5 11, 5 11' and 5 11 " includes corresponding ink filling ports 5 14 and 5 15, 5 14' and 5 1 Y, and 51C and 5 15 ". Projections 516a and 516b, Figure 2, are integrally formed with the inner surface of lid 5 16 and are positioned in foam chamber 5 11, so as to surround filling ports 515 and 514, respectively. Porous member 520 is compressed by projections 516a and 516b against the bottom wall of foam chamber 511 in which ink supply port 513 is formed. Projections 516a' and 516W and 51.6a" and 516W' are similarly formed in the inner wall of lid 5 16, and are positioned in foam chambers 5 11' and 5 11 ", which contain ink supply ports 5 13' and 5 13 ", respectively, as shown in Figure 3.

Projection 516a which opposes ink supply port 513 is formed with its lower tip located at a position lower than the lower tip of projection 516b, whereby the portion of porous member 520 in the vicinity of ink supply port 513 is compressed to the greatest extent.

Protrusion portions 522, 522' and 52T' (collectively "522"), which cooperate with lid 516 to compress porous members 520, 520' and 52W respectively are formed on the bottom of each of foam chambers 5 11, 5 11' and 511 ". Recesses 523, 523' and 523 " (collectively "52Y), which define spaces having a fixed opening area, are formed at the upper end of respective protrusion portions 522. Through holes 524, 524' and 52C (collectively "52C) are disposed within the respective protrusion portions M. One end of each through hole 524 is in fluid communication with the spaces deflined by recesses 523 and the other end with a respective packing (collectively "530"), which will be hereinafter described. Filters 525, 525' and 52Y' (not shown) (collectively "525") are fixed to the upper end of recesses 523 respectively.

Packing members 530, of which only one is shown, are disposed at the lower end of ink supply ports 513, 513' and 5W respectively and are made of a resilient material such as rubber. Packing members 530, are configured as a funnel-shaped packing which opens upward. The lower ends of tubular portions 531 are thicker than the other portions. The respective upper peripheral edges 533 of taper portions 532 of respective packing members 530 contact with step portions 513a of respective ink supply ports 513, 513' and 51Y. Each packing member 530 is formed with protrusions 535 received by groove portion 527 within the inner wall of ink supply port 513. The boundary between tubular portions 531 and taper portions 532, are configured as thin connection portions 534.

In this design, packing members 530 are fixed by tubular portions 531 to respective ink supply ports 513. Additionally, upward movement of upper peripheral edges 533 is prevented by respective step portions 513a. Thus, even when the respective ink supply needle is inserted or extracted, packing members 530 are adequately fixed to ink supply ports 513. Since taper portions 532 serve to attain the hermetic seal between the packing member of the respective ink supply port 513 and the ink supply needle by the respective thin connection portions 534, the taper portions can be moved somewhat without causing deformation. Consequently, the air tight seal between the respective packing member and ink supply needle can be maintained while accommodating a relative misalignment between the respective ink supply needle and ink supply port.

Communicating holes 519, 519' and 519" are formed in centre partition wall 510, which separates foam chambers 511, 511' and 511 " from ink chambers 512, 512' and 512" respectively. Slots 519, 519a' and 519a" which extend to a predetermined height are formed to be in communication with communicating holes 519, 519' and 519" respectively for gas-liquid replacement. Between each respective pair of foam and ink chambers 5 11 and 512, 511' and 512', and 5 11 " and 512", porous members 520, 520' and 52W are housed in the foam chambers 5 11, 511' and 511 " respectively in such a manner that each porous member is held against the respective communicating hole 519, 0 519' and 519". Ribs 518, 518' and 518" are formed on a back wall 501a of container 12 501 within a respective ink chamber 512, 512' and 5.12". An individual communication hole is formed between each respective chamber pair 511, 512, and extends along only a portion of the length of partition 5 10 formed thereat.

In a second embodiment of the invention an ink cartridge is utilized for a single colour ink. A cartridge 5 100 for a single colour, or black ink can be made smaller in size than that for colour inks, but the ink chamber 5112 for black ink would have a larger capacity than each of the corresponding chambers for a colour ink. According to the second embodiment of the invention, a cartridge for black ink is shown in Figure 5 having a partition wall 5117 formed within a container 5 100 so as to extend between centre partition wall 5110 which separates a foam chamber 5111 from an ink chamber 5112 and a side wall 5 100a of main container 5 100, thereby dividing ink chamber 5112 into two cells 5112a and 5112b. This structure prevents container 5 100 from being deformed by a negative pressure produced during the ink filling process which will be hereinafter described, or by an external pressure during usage, thereby preventing any ink from leaking. Cells 5 1 12a and 5 1 12b are retained in fluid communication with foam chamber 5 111 via a communicating hole 5 119 in centre partition 5 110 which extends along only a portion of the length of partition 5 110. In addition, a communicating hole may be formed in the lower portion of partition wall 5 117.

On the inner face of wall 5100a, which can easily be seen when the cartridge is mounted on a carriage, a plurality of ribs 5 118 are formed which extend vertically along inner face 5 1 00a. Th:se ribs allow ink to flow more easily down along wall 5 1 00a, and the user can easily recognize the amount of ink remaining in the cartridge by seeing the ink level.

Reference is now made to Figures 6(a) and 6(b) which depict lid 5 16 constructed in accordance with the first embodiment of the invention. Ink filling holes 514, 514' and 514", and 515, 51Y' and 51Y' are formed in the regions of lid 516 corresponding to the 0 placement of porous members 520, 520' and 52W' within container 501. Air communicating ports 541, 541' and 541" are connected to ink filling holes 514, 514' and 514" via grooves 540, 540' and 540", respectively.

13 When a seal 542 for covering ink filling holes 514, 514' and 51C, 515, 515' and 515", and air vent ports 541, 541' and 54P' is fixed to the upperside of lid 516, Figure 6(b), after ink from chambers 5 11, 5 11' and 5 11 " are filled, grooves 540, 540' and 54T form capillary tubes with seal 542. A tongue piece 545 of seal 542, which protrudes from lid 5 16, is formed with a neck portion 543 disposed in seal 542 at a midpoint of the route of air vent ports 541, 541 ' and 541 ". When tongue piece 545 is peeled from lid 5 16, tongue piece 545 is easily separated from seal 542. This in turn exposes air vent ports 541, but no other portions of the underside of seal 542.

In a preferred embodiment, seal 542 is formed with patterns such as characters and illustrations printed on its main portion 544 which permanently seals grooves 540, 540' and 54T. Patterns, colours, or other printing different from that printed on main portion 544 of seal 542 may be placed on tongue piece 545 which is connected to main portion 544 of seal 542 via neck portion 543.

For example, in a further preferred embodiment, the main portion 544 of seal 542 has a blue background, black characters and other illustrations printed thereon. The background colour of tongue piece 545 is a colour such as yellow or red which contrasts with the background colour of main portion 544. Characters and illustrations are printed on the background in colours which are mainly black or blue. In this way, main portion 544 and tongue piece 545 are- distinguished from each other in colour and pattern. Consequently, it is possible to call the user's attention to the need for the removal of tongue piece 545.

Each of ink supply ports 513, 513' and 51Y are sealed by a film 546 (Figure 2), and ink filling needles are hermetically inserted into the ink filling holes 514, 514' and 514" and 515, 515' and 51Y' respectively. The first of filling holes 514, 514' and 51C is connected to evacuating means, and the second of the filling holes 515, 515' and 51Y' is closed.

The evacuating means reduces the pressure in each of foam chambers 511, 511' and 5IF' and in each of ink chambers 512, 512' and 512". When the pressure is reduced to a predetermined value, the evacuating operation is stopped and the first filling 14 hole is closed. Thereafter, the second filling hole is placed in fluid communication with a measuring tube filled with ink. Ink contained in the measuring tube is drawn into the evacuatedcontainer and is then absorbed by respective porous member 520, 520' and 520" and thereafter flows into ink chamber 512, 512' and 512" via communicating holes 519, 519' and 51C respectively.

After the specified amount of ink flows into the appropriate ink chamber, seal 542 is fixed to the outer surface of lid 516 so that the ink filling holes 514, 514' and 51C and 515, 515' and 515", grooves 540, 540' and 540", and communicating ports 541, 541' and 54P are sealed under reduced pressure. Seal 542 thereafter maintains the reduced pressure states of foam chambers 5 11, 5 11' and 5 11 " and ink chambers 5 12, 512' and 512".

Before use of the cartridge, tongue piece 545 of seal 542 is then peeled off so that tongue piece 545 is broken at neck portion 543 and is separated from main portion 544. Thus, ink filling holes 514, 514' and 51C are placed in fluid communication with air vent ports 541, 54 1' and 541 " via grooves 540, 540' and 54T. Also, foam chambers 511, 511' and 511" are placed in fluid communication with air vent ports 541, 541' and 1 541" and therefore ambient air, via grooves 540, 540' and 540". Thus, while the ink is prevented from evaporating, the ink cartridge is ventilated.

Reference is now made to Figures 7(a) and 7(b), wherein an ink supply port 513 of the ink cartridge is positioned so as to be aligned with an ink supply needle 550 of the recording head. Thereafter the ink cartridge is pushed toward the recording head upon insertion of the ink cartridge. A taper portion 551 of ink supply needle 550 passes through a film seal 546 and engages the hole of packing member 530 as shown in Figure 7(a). Since packing member 530 opens upward, packing member 530 allows ink supply needle 550 to pass therethrough while packing member 530 is resiliently deformed by taper portion 551 of ink supply needle 550.

When the cartridge is used, ink supply needle 550 passes through packing member 530. The resiliency of connection portion 534 of packing member 530 enables taper portion 532 to engage ink supply needle 550. Even if ink supply needle 550 of the C recording head and the centre of packing member 530 are somewhat misaligned, ink supply port 513 and ink supply needle 550 are hermetically sealed.

To conduct ink into the recording head after the ink cartridge is mounted, or to recover the ink ejection performance, a negative pressure is applied to the recording head and through ink supply needle 550 so that ink in the cartridge flows through ink supply needle 550 and into the recording head. Because of the pressure difference, this high negative pressure applied to the cartridge causes taper portion 532 of packing member 530, which hermetically seals and isolates the cartridge from ambient air, to deform upward in Figure 7(a) toward the interior of the ink cartridge. Thus, the pressure difference aids in causing taper portion 532 of packing member 530 to be resiliently pressed against ink supply needle 550, and thereby aids in hermetically sealing the ink cartridge.

Even if ink supply needle 550 is not positioned completely through packing member 530, the resilient force in taper portion 532 of packing member 530 allows taper portion 532 to remain in contact with ink supply needle 550 as long as the tapered portion 551 of ink supply needle 550 remains in contact with taper portion 532 as shown in Figure 7(b). Consequently, it is possible to secure the air tightness of packing member 530 and ink supply needle 550 even if the needle is not properly inserted.

Since the tip of ink supply needle 550 is sealed upon contact with packing member 530, the dead space in the cartridge can be made very small, and any air bubbles which may be produced by the piston effect upon insertion of the cartridge onto the recording head are prevented from entering the cartridge.

When a negative pressure is applied from the nozzle openings of the recording head, ink absorbed by porous member 520 flows into the recording head via through hole 524 and through holes 552 of ink supply needle 550. When ink of a predetermined amount is consumed from porous member 520 and the ink level in porous member 520 is reduced, the pressure of ink chamber 512 overcomes the holding force of porous member 520 in the vicinity of communicating hole 519, so that air bubbles enter ink 16 chamber 512 via communicating hole 519. Consequently, the pressure in an ink chamber 5 12 is increased and ink therefore flows into a foam chamber 5 11.

The ink flowing into foam chamber 511 is absorbed by porous member 520 and causes the ink level in foam chamber 5 11 to be raised. At the instant when the ink holding force of porous member 520 in the vicinity of communicating hole 519 is balanced with the pressure in ink chamber 5 12, the flow of ink from ink chamber 5 12 into foam chamber 5 11 is stopped.

The graph of Figure 8 illustrates this process. In the figure, the letter F indicates the pressure level in porous member 520 of foam chamber 5 11, and the letter G indicates the ink level in ink chamber 512. When a predetermined amount of ink w l which was initially contained in porous member 520 is consumed so that the ink level in porous member 520 is reduced to a predetermined value at which the pressure in ink chamber 5 12 overcomes the ink holding force of porous member 520 in the vicinity of communicating hole 519, ink gradually flows in a stepwise manner from ink chamber 5 12 into the foam chamber 5 11. This process occurs until the balance between the pressure of the ink chamber 512 and the ink holding force of porous member 520 in the vicinity of communicating hole 5 19 is restored. As a result, although the ink level in ink chamber 5 12 is gradually reduced, the ink level in porous member 520 can be maintained at a substantially constant level so that ink is supplied to the recording head by a constant pressure difference at a constant rate.

After a predetermined amount of ink w2 is consumed by the recording head, no ink will remain in ink chamber 512, but the amount of ink contained in porous member 520 will be at a level equal to the level when ink was intermittently being supplied to foam chamber 511 from ink chamber 512. Therefore, printing can be continued using the amount of ink absorbed in porous member 520, although no further ink is available in ink chamber 5 12 to replenish the ink supply into porous member 520. After a predetermined amount of ink w3 is consumed during printing, the ink supply in porous member 520 will be deleted, and the ink cartridge will no longer support printing.

17 During the entire printing operation from when all the ink contained in ink chamber 5 12 has been absorbed in porous member 520 until the ink is depleted, a constant amount of ink is supplied to the recording head. The depletion of ink from ink chamber 512 indicates the impending depletion of ink in the ink tank cartridge. If a fresh cartridge is inserted at this stage, it is possible to ensure a constant supply of ink to the recording head without interruption.

As described above, the inner space of the ink cartridge of the invention must be maintained at a negative pressure during the printing process. In addition to the achievement of the above-described hermetic seal between the ink supply port and the ink supply needle, the transfer of ink from ink chamber 512 to the foam chamber 511 must be performed properly to ensure a constant flow of ink to the recording head. Hereinafter, the structure for controlling the supply of ink from ink chamber 512 to foam chamber 511 will be described.

Reference is now made to Figure 9 which depicts the boundary between foam chamber 511 and ink chamber 512 in a third embodiment of the invention. Like numerals are utilized to indicate like, structures, the primary difference between this embodiment and the first embodiment being a step portion formed in hole 519.

A step portion 560 is formed in communicating hole 519. A portion 563 of the base of ink chamber 5 12 is higher than that of foam chamber 5 11, step portion 560 being the dividing point. A groove 561 connecting the foam and the ink chamber is formed in the lower part of step portion 560.

Porous member 520 is in contact with communicating hole 519 and is received by step portion 560 so that the portion of porous member 520 in the vicinity of communicating hole 519 is compressed, whereby the required pressure difference between ink chamber 512 and foam chamber 511 via communicating hole 519 can be attained. When the ink level of ink chamber 512 is reduced to a low level, groove 561 0 enables ink from ink chamber 512 to be collected and then absorbed by porous member 520 in foam chamber 511. Consequently, all of the ink in ink chamber 512 can be supplied to the recording head for printing without wasting any ink.

0 0 18 Reference is now made to Figure 10, which depicts an ink cartridge constructed in accordance with a fourth embodiment of the invention. Again, like numerals are used to indicate like structures, the primary difference between this embodiment and the first embodiment is the different levelled bottoms of the respective chambers.

The bottom face 564 of ink chamber 512 is higher than the bottom face 567 of foam chamber 5 11, thereby forming a step portion 5 62. Step portion 5 62 receives the lower portion of porous member 520 so that the portion of porous member 520 in the vicinity of communicating hole 519 is compressed. When required, a slope 563 which is directed from the ink chamber 512 to the foam chamber 511 may be formed to aid in the supply of ink. Since slope 563 allows ink in ink chamber 512 to flow more easily toward foam chamber 511, irrespective of the inclination of the carriage, ink from ink chamber 5 12 can be constantly supplied to the recording head.

Reference is now made to Figures 11 and 12 which depict an ink jet cartridge constructed in accordance with a fifth embodiment of the invention. Like structures are indicated by like reference numerals, the primary difference between this embodiment and the first embodiment is the formation of a through hole. This embodiment is the same as shown in Figures 4 and 5.

Groove 5 19a (Figures 4 and 5) is formed in the face of centre partition 5 10 separating foam chamber 5 11 from ink chamber 5 12. Groove 5 19a is formed in the face of partition 510 on the side of the foam chamber 511 and is in communication with the upper portion of communicating hole 5 19 of centre partition 5 10 within the respective chambers 511, 512. In order to allow air to pass from ink chamber 512 to foam chamber 511 and to retain these chambers in fluid communication with each other, a through hole 519b is formed in the lower end of the groove 519a. Thus, the upper portion of porous member 520 which exhibits a relatively small capillary force is maintained in fluid communication with communicating hole 519 via the space formed by thin groove 5 19a. Therefore, ink can be smoothly replaced with air so that ink in ink chamber 5 12 constantly flows into foam chamber 5 11, thereby preventin - too much or not enough ink from being supplied.

19 Reference is now made to Figures 13 and 14 which depict an ink cartridge constructed in accordance with a sixth embodiment of the invention. Like numerals are utilized to depict like structures, the primary difference being the use of a projection into foam chamber 5 11.

A horseshoe-shaped projection 565 is formed on the bottom of foam chamber 5 11 as is shown in Figure 14. Projection 565 ensures a space in the vicinity of communicating hole 519 so that ink from ink chamber 512 can easily flow into foam chamber 511.

As described above, foam chamber 5 11 and ink chamber 512 are separated from each other by the single centre partition 510. In seventh or eighth embodiments of a single-colour ink cartridge, as shown in Figures 15 and 16 respectively, an ink chamber 571 may be formed so as to surround two or three sides of a foam chamber 570, and a communicating hole 573 may be formed in at least one of the walls 572 separating the foam chamber 570 from the ink chamber 571. An exit port 574 is positioned within foam chamber 570. An ink cartridge of this design can store an amount of ink which is relatively large as compared with the volume of the whole ink cartridge. Furthermore, because of the location of the chambers, the user can easily see if replacement of the ink cartridge is required because of depletion of the ink.

Reference is now made to Figures 17 and 18 wherein an inkjet printer cartridge constructed in accordance with a ninth embodiment of the invention is provided. This embodiment is similar to the first embodiment, the primary difference being the use of a resilient 0-ring 5300 which is retained in contact with the peripheral face of an ink supply needle of the recording head upon insertion of the ink supply needle into the ink supply cartridge. However, this inkjet printer results in other problems solved by the 0 first embodiment. A large frictional force may be produced when mounting the cartridge on the carriage and inserting the ink supply needle into the cartridge. This results in an 0 extra strain on the recording head and the carriage. Furthermore, 0-ring 5300 is supported at its periphery by the body 5302 of the cartridge. If there is a misalignment C between the cartridae and the ink supply needle of the recording head upon insertion of c the ink supply needle in the ink supply cartridge, it is very difficult to mount the cartridge. Furthermore, when a three colour ink cartridge in which tanks 5304, 5306 and 5308 for the three colour inks are integrated into one piece as shown in Figure 18, it is extremely difficult to mount such a cartridge on the recording head if the cartridge and any of the ink supply needles are misaligned.

It will thus be seen that the objects set forth above, among those made apparent from the preceding description are efficiently attained and, since certain changes may be made in carrying out the above construction and method set forth without departing from the spirit and scope of the invention, it is intended that all matter contained in the above description and shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

21

Claims (1)

1 An ink tank cartridge for an ink-jet type recording apparatus, comprising: a plurality of first chambers; a plurality of second chambers, each second chamber being adjacent to and associated with afirst chamber; a plurality of partition walls disposed in said cartridge, each said partition being formed with a communicating hole formed therein disposed between said associated chambers, said communicating hole being positioned in the vicinity of the bottom of said partition wall and extending only a portion of the width of said partition wall as viewed in the direction of said bottom of said partition wall; and a plurality of ink supply ports, each extending through a wall of a respective one of said plurality of second chambers, said plurality of ink supply ports supplying ink to the exterior of said cartridge, all of said first chambers and associated second chambers being formed as an integral unit.

2. The ink cartridge of claim 1, and including a porous member in each of said second chambers positioned to deliver ink to its associated ink supply port and an air vent port communicating between each said second chamber and the exterior of said C cartridge at a location spaced from said ink supply port and communicating hole.

3. The ink cartridge of claim 2, wherein the porous member associated with each VP second chamber and the associated first chamber contain ink different from the ink in the other first and second chambers.

4. The ink tank cartridge of claim 2 or 3, wherein the porous member in each said second chamber and the associated first chamber contain ink, the pressure in each of said first chambers and each of said associated second chambers being at a value less than atmospheric pressure.

22 5. The ink tank cartridge of claim 4, wherein a pressure balance between each of said first chambers and each of said associated second chambers is maintained by the surface tension of each of said associated porous members in the vicinity of each of said associated communicating holes, each said porous member resiliently contacting said associated communicating hole, said pressure balance maintaining ink in each of said respective first chambers.

6. The ink tank cartridge of claim 5, wherein each said porous member, associated first and second chambers, partition wall, communication hole ink supply port and air vent port are positioned and dimensioned so that when said ink impregnated in each of said associated porous members is at least partially transmitted through said ink supply port, said pressure balance between said associated chambers is no longer maintained and ink is supplied from the first chamber to the associated porous member in the associated second chamber as required until the pressure balance is restored.

7. The ink tank cartridge of any one of the preceding claims, further comprising an associated step portion formed at a lower portion of each of said communicating holes, a groove connecting said associated first and second chambers being formed in said ink cartridge below said associated step portion.

8. The ink tank cartridge of any one of the preceding claims, further comprising a protrusion portion formed on an inner surface of said partition wall in each of said second chambers, each said protrusion portion maintaining a space about said associated communicating hole to aid in the flow of ink therethrough.

9. The ink tank cartridge of any one of the preceding claims, further comprising a step portion formed below each of said communicating holes in said partition wall.

23 10. The ink tank cartridge of claim 9, wherein the part of each of said step portions adjacent said associated first chamber is higher than the part adjacent said associated second chamber.

11. The ink tank cartridge of any of the preceding claims, further comprising a respective vertically extending thin groove formed in each said partition wall above each communicating hole and on the side of the associated second chambers, each of said C grooves being in fluid communication with each associated communicating hole, each of C said grooves aiding in the flow of air and ink between said associated first and second chambers.

12. The ink tank cartridge of any one of claims 2 to 11, further comprising a projection formed on an inside wall of each of said second chambers disposed on a surface of said second chamber opposite said associated ink supply port, said projections compressing said associated porous members against said associated ink supply ports.

13. The ink tank cartridge of claim 12, wherein each said ink supply port includes a projection including its entrance projecting into said second chamber.

14. The ink tank cartridge of claim 12 or 13, wherein the volume of each of said 0 porous members before placement in a second chamber is larger than the volume of the associated second chamber in which it is received.

15. The ink tank cartridge of any one of claims 2 to 14, wherein the volume of each of said porous members is larger than the capacity of each of said associated second chambers.

16. The ink tank cartridge of any one of claims 2 to 15, further comprising at least one C chamber partition wall, said chamber partition wall extending from each said partition 24 wall and dividing said first chamber into a plurality of such chambers while permitting communication between each such chamber and the associated second chamber through the associated communicating hole.

17. The ink tank cartridge of any one of the preceding claims, further comprising a respective vertically extending rib formed on an inner surface of said first chamber, each of said ribs assisting in the flow of ink.

18. The ink tank cartridge of any one of the preceding claims, wherein said first chamber and said second chamber are maintained at a pressure less than atmospheric pressure and said ink cartridge further comprises a plurality of air vent ports formed in a surface of said cartridge, each having an air-impermeable sealing member for selectively sealing said air vent ports when said ink cartridge is not in use and unsealing said air vent ports when said ink cartridge is to be used.

19. The ink tank cartridge of claim 18, wherein each of said air vent ports is formed in part as a groove on the outside surface of a wall of said second chamber.

20. The ink tank cartridge of claim 18 or 19, wherein said outside surface is of a top lid.

2 1. The ink tank cartridge of claim 18, 19 or 20, wherein said sealing member comprises a main portion, and a tongue piece which is removably connected to said main portion via a neck portion.

11, wherein at least one of different patterns and 12. The ink tank cartridge of claim C> colours are printed on said main portion and said tongue piece, said neck portion acting as a boundary between said main portion and said tongue piece.

23. The ink tank cartridge of any one of the preceding claims, further comprising at least one chamber partition wall extending from each partition, said chamber partition walls dividing each said first chambers into a plurality of sub-chambers.

24. The ink tank cartridge of any one of claims 2 to 23, further comprising a projection formed on an inside wall of each of said second chambers disposed on a surface of said second chamber opposite said associated ink supply port, said projections compressing said associated porous members against said associated ink supply ports.

25. The ink tank cartridge of any one of the preceding claims, wherein each said ink supply port includes a portion including its entrance projecting into said second chamber.

C 26. The ink tank cartridge of claim 24, wherein the volume of each of said porous members before placement in a second chamber is larger than the volume of the associated second chamber in which it is received.

27. The ink tank cartridge of any of claims 18 to 26, wherein the volume of each of said porous members before placement in a second chamber is larger than the volume of the associated second chamber in which it is received.

28. The ink tank cartridge of any of claims 18 to 27, further comprising a respective vertically extending rib formed on an inner face of each of said first chambers, each of said ribs assistina in the flow of ink.

C 18, wherein each said air vent port 29. The ink tank cartridge of any one claims 18 to is formed in part as a meandering groove.

0 0 30. The ink tank cartridge of any one of the preceding claims, wherein said second C chamber is a foam chamber and said first chamber is an ink chamber.

26 3 1. The ink tank cartridge above of any one of the preceding claims, wherein said cartridge is constructed to be removably mounted on said recording apparatus so that one of a plurality of ink supply needles of said apparatus is received in each ink supply port.

32. An ink-get type recording apparatus for outputting ink onto a recording medium, comprising: a recording head for ejecting ink; and a multi-colour ink tank cartridge removably mountable onto said recording head of said ink-jet type recording apparatus for delivery of ink thereto, said ink tank cartridge, including: a plurality of first chambers; a plurality of second chambers, each second chamber being adjacent to and associated with a first chamber; a plurality of partition walls disposed in said cartridge, each said partition being formed with a communicating hole formed therein disposed between said associated chambers, said communicating hole being positioned in the vicinity of the bottom of said partition wall and extending only a portion of the width of said partition wall as viewed in the direction of said bottom of said partition wall; and a plurality of ink supply ports, each extending through a wall of a respective one of said plurality of second chambers, said plurality of ink supply ports supplying ink to the exterior of said cartridge, all of said first chambers and associated second chambers being formed as an integral unit.

33. The ink-jet type recording apparatus of claim 32, and including a porous member in each of said second chambers positioned to deliver ink to its associated ink supply port and an air vent port communicating between each said second chamber and the exterior 0 of said cartridge at a location spaced from said ink supply port and communicating hole.

C 27 34. The ink-jet type recording apparatus of claim 33 or 34 wherein the porous member associated with each second chamber and the associated first chamber contain ink different from the ink the other first and second chambers.

35. The ink-jet type recording apparatus of claim 33 or 34, wherein the porous member in each said second chamber and the associated first chamber contain ink, the pressure in each of said first chambers and each of said associated second chambers being at a value less than atmospheric pressure.

36. The ink-jet type recording apparatus of claim 35, wherein a pressure balance between each of said first chambers and each of said associated second chambers is maintained by the surface tension of each of said associated porous members in the vicinity of each of said associated communicating holes, each said porous member resiliently contacting said associated communicating hole, said pressure balance maintaining ink in each of said respective first chambers.

37. The ink-jet type recording apparatus of claim 36, wherein each said porous member, associated firs and second chambers, partition wall, communication hole ink supply port and air vent port are positioned and dimensioned so that when said ink impregnated in each of said associated porous members is at least partially transmitted through said ink supply port, said pressure balance between said associated chambers is no longer maintained and ink is supplied from the first chamber to the associated porous member in the associated second chamber as required until the pressure balance is restored.

38. The ink-jet type recording apparatus of any one of claims 32 to 37, further comprising a respective vertically extending thin groove formed in each said partition wall above each communicating hole and on the side of the associated second chambers, each of said grooves being in fluid communication with each associated communicating 28 hole, each of said grooves aiding in the flow of air and ink between said associated first and second chambers.

39. The ink-jet type recording apparatus of any one of claims 33 to 38, further comprising a projection formed on an inside wall of each of said second chambers disposed on a surface of said second chamber opposite said associated ink supply port, said projections compressing said associated porous members against said associated ink supply ports.

40. The ink-jet type recording apparatus of claim 39, wherein each said ink supply port includes a projection including its entrance projecting into said second chamber.

0 41. The ink-jet type recording apparatus of claim 39 or 40, wherein the volume of each of said porous members before placement in a second chamber is larger than the volume of the associated second chamber in which it is received.

42. The ink-jet type recording apparatus of any one of claims 33 to 41, wherein the volume of each of said porous members is larger than the capacity of each of said associated second chambers.

43. The ink-jet type recording apparatus of any one of claims 33 to 42, further comprising at least one chamber partition wall, said chamber partition wall extending from each said partition wall and dividing said first chamber into a plurality of such chambers while permitting communication between each such chamber and the associated second chamber through the associated communicating hole.

C 44. The ink-jet type recording apparatus of any one of claims 32 to 43, further comprising a respective vertically extending rib formed on an inner surface of said first chamber, each of said ribs assisting in the flow of ink.

29 45. The ink-jet type recording apparatus of any one of claims 32 to 44, wherein said first chamber and said second chamber are maintained at a pressure less than atmospheric pressure and said ink cartridge further comprises a plurality of air vent ports formed in a surface of said cartridge, each having an air-impermeable sealing member for selectively sealing said air vent ports when said ink cartridge is not in use and unsealing said air vent ports when said ink cartridge is to be used.

46. The ink-jet type recording apparatus of claim 45, wherein each of said air vent ports is formed in part as a groove on the outside surface of a wall of said second chamber.

47. The ink-jet type recording apparatus of claim 45 or 46, wherein said outside surface is of a top lid.

48. The ink-jet type recording apparatus of claim 45, 46 or 47 wherein said sealing member comprises a main portion, and a tongue piece which is removably connected to said main portion via a neck portion.

49. The ink-jet type recording apparatus of claim 48, wherein at least one of different patterns and colours are printed on said main portion and said tongue piece, said neck portion acting as a boundary between said main portion and said tongue piece.

50. The ink-jet type recording apparatus of any one of claims 32 to 49, further comprising at least one chamber partition wall extending from each partition, said chamber partition walls dividing each said first chambers into a plurality of subchambers.

1. The ink-jet type recording apparatus of any one of claims 33 to 50, further comprising a projection formed on an inside wall of each of said second chambers disposed on a surface of said second chamber opposite said associated ink supply port, said projections compressing said associated porous members against said associated ink supply ports.

52. The ink-jet type recording apparatus of any one of claims 45 to 51, wherein each said air vent port is formed in part as a meandering groove.

53. The ink-jet type recording apparatus of any one of claims 32 to 52, wherein said second chamber is a foam chamber and said first chamber is an ink chamber and said first chamber is an ink chamber.

54. The ink-jet type recording apparatus of any one of claims 32 to 53, wherein said cartridge is constructed to be removably mounted on said recording apparatus so that one of a plurality of ink supply needles of said apparatus is received in each ink supply port.

55. A system for supplying ink to an ink-jet type recording apparatus and outputting ink onto a recording medium, said system comprising: a recording head for ejecting ink; and a multi-colour ink tank cartridge removably mountable onto said recording head of said ink-jet type recording apparatus for delivery of ink thereto, said ink tank cartridge including: a plurality of first chambers; a plurality of second chambers, each second chamber being adjacent to and associated with a first chamber; a plurality of partition waRs disposed in said cartridge, each said partition being 0 formed with a communicating hole formed therein disposed between said associated chambers, said communicating hole being positioned in the vicinity of the bottom of said Z. t 31 partition wall and extending only a portion of the width of said partition wall as viewed in the direction of said bottom of said partition wall; and a plurality of ink supply ports, each extending through a wall of a respective one of said plurality of second chambers, said plurality of ink supply ports supplying ink to the exterior of said cartridge, all of said first chambers and associated second chambers being formed as an integral unit.

0 56. The system of claim 55, and including a porous member in each of said second chambers positioned to deliver ink to its associated ink supply port and an air vent port communicating between each said second chamber and the exterior of said cartridge at a location spaced from said ink supply port and communicating hole.

57. The system of claim 56, wherein the porous member associated with each second chamber and the associated first chamber contain ink different from the ink in the other first and second chambers.

58. The system of claim 56 or 57, wherein the porous member in each said second chamber and the associated first chamber contain ink, the pressure in each of said first chambers and each of said associated second chambers being at a value less than atmospheric pressure.

59. The system of claim 58, wherein a pressure balance between each of said first chambers and each of said associated second chambers is maintained by the surface tension of each of said associated porous members in the vicinity of each of said associated communicating holes, each porous member resiliently contacting said associated communicating hole, said pressure balance maintaining ink in each of said respective first chambers.

32 60. The system of claim 59, wherein each said porous member, associated first and second chambers, partition wall, communication hole ink supply port and air vent port are positioned and dimensioned so that when said ink impregnated in each of said associated porous members is at least partially transmitted through said ink supply port, said pressure balance between said associated chambers is no longer maintained and ink is supplied from the first chamber to the associated porous member in the associated second chamber as required until the pressure balance is restored.

61. The system of any one of claims 55 to 60, further comprising a respective vertically extending thin groove formed in each said partition wall above each communicating hole and on the side of the associated second chambers, each of said grooves being in fluid communication with each associated communicating hole, each of 0 said grooves aiding in the flow of air and ink between said associated first and second chambers.

62. The system of any one of claims 55 to 61, further comprising a projection formed on an inside wall of each of said second chambers disposed on a surface of said second chamber opposite said associated ink supply port, said projections compressing said associated porous members against said associated ink supply ports.

63. The system of claim 62, wherein said ink supply port includes a projection including its entrance projecting into said second chamber.

64. The system of claims 62 or 63, wherein the volume of each of said porous members before placement in a second chamber is larger than the volume of the associated second chamber in which it is received.

65. The system of any one of claims 56 to 64, wherein the volume of each of said porous members is larger than the capacity of each of said associated second chambers.

33 66. The system of any one of claims 56 to 65, further comprising at least one chamber partition wall, said chamber partition wall extending from each said partition wall and dividing said first chamber into a plurality of such chambers while permitting communication between each such chamber and the associated second chamber through the associated communicating hole.

67. The system of any one of claims 56 to 66, further comprising a respective vertically extending rib formed on an inner surface of said first chamber, each of said ribs assisting in the flow of ink.

68. The system of any one of claims 55 to 67, wherein said first chamber and said second chamber are maintained at a pressure less than atmospheric pressure and said ink cartridge further comprises a plurality of air vent ports formed in a surface of said cartridge, each having an air-impermeable sealing member for selectively sealing said air vent ports when said ink cartridge is not in use and unsealing said air vent ports when said ink cartridge is to be used.

69. The system of claim 68, wherein each of said air vent ports is formed in part as a groove on the outside surface of a wall of said second chamber.

70. The system of claim 68 or 69, wherein said outside surface is of a top lid.

The system of claim 68, 69 or 70, wherein said sealing member comprises a main portion, and a tongue piece which is removably connected to said main portion via a neck portion.

34 72. The system of claim 71, wherein at least one of different patterns and colours are printed on said main portion and said tongue piece, said neck portion acting as a boundary between said main portion and said tongue piece.

73. The system of any one of claims 55 to 72, further comprising at least one chamber partition wall extending from each partition, said chamber partition walls dividing each said first chambers into a plurality of subchambers.

74. The system of any one of claims 55 to 73, further comprising a projection formed on an inside wall of each of said second chambers disposed on a surface of said second chamber opposite said associated ink supply port, said projections compressing said associated porous members against said associated ink supply ports.

0 75. The system of any one of claims 68 to 74, wherein each said air vent port is formed in part as a meandering groove.

76. The system of any one of claims 55 to 75, wherein said second chamber is a foam chamber and said first chamber is an ink chamber.

77. The system of any one claims 55 to 77, wherein said cartridge is constructed to be removably mounted on said recording apparatus so that one of a plurality of ink supply needles of said apparatus is received in each ink supply port.

78. A method for providing ink to an ink-jet type recording head, comprising the steps C of:

providing an ink tank cartridge having a plurality of first chambers adapted to store ink and a plurality of second chambers adapted to receive a respective porous member impregnated with ink, each of said first and second chambers being separated from each other by a partition wall; communicating ink between said associated first and second chambers through a communicating hole adjacent to the bottom of said partition and extending only a portion of the width of said partition wall as viewed in the direction of said bottom of said partition wall, withdrawing ink from each porous member in each second chamber through an ink supply port extending through a wall of each second chamber; and providing ambient air to each second chamber at a location spaced from said ink supply port.

79. The method of claim 78, further comprising the steps of' maintaining the pressure in each of said first and second chambers below normal atmospheric pressure; maintaining a pressure balance between each pair of associated first and second chambers by the surface tension of said porous member in the vicinity of said communicating hole; the withdrawal of ink from a porous member through an associated ink supply port upsetting the pressure balance between said associated first and second chambers so that ink flows from said first chamber to said second chamber until said pressure balance is restored.

80. The method of claim 78 or 79, further comprising the step of: forming air vents at least in part as winding grooves in a surface of said ink tank cartridge to protect said ink against evaporation.

C 81. The method of claim 80, further comprising the steps of:

sealing said grooves with a seal member; 0 removing a portion of said seal to place the interior of said ink supply tank in fluid C communication with ambient air through said winding grooves.

0 36 82. An ink tank for supplying ink, the ink tank having a first chamber and a second chamber separated by a partition wall having a hole formed therein for allowing ink to pass between the chambers, wherein the communicating hole is positioned generally at the lower end of the partition wall in normal use, and/or the hole extends only along a part of the width of the partition wall.

83. An ink tank cartridge, an inkjet recording apparatus, a system for supplying ink to an ink-jet recording -mparatus or a method of providing ink to an ink-jet recording apparatus substantia. as hereinbtfore uescribed with reference to and/or as illustrated in any one or any combination of the accompanying drawings.