WO2007015083A2

WO2007015083A2 - Sealing arrangement for the ink supply port of an ink cartridge

Info

Publication number: WO2007015083A2
Application number: PCT/GB2006/002869
Authority: WO
Inventors: John William Studholme
Original assignee: Dynamic Cassette International Ltd.
Priority date: 2005-08-01
Filing date: 2006-08-01
Publication date: 2007-02-08
Also published as: GB0515806D0; WO2007015083A3; GB2428639A; GB2428639B; EP1948445A2; GB0615291D0

Abstract

An ink cartridge (10) for a printer (64) comprises a container (12) for holding ink and ink supply port (14) to receive an ink withdrawal needle (60) of the printer (64). The cartridge (10) further comprises an elastomeric member (30) in the ink supply port (14) to resiliently abut against and thereby seal against the outer periphery (90) of the ink withdrawal needle (60) in use, and a seal (44) to seal the ink supply port (14) and be pierced by the ink withdrawal needle (60). The seal (44) is mounted on a mounting piece (36) which is inserted into the outer end of the ink supply port (14) before the elastomeric member (30) in assembly of the cartridge (10). The seal (44) is thus positioned in the ink supply port (14) so that the ink withdrawal needle (60) passes through the elastomeric member (30) before piercing the seal (44).

Description

An Ink Cartridge

The invention relates to an ink cartridge.

A known ink cartridge for a printer is disclosed in EP-A-553535. The cartridge has a downwardly facing ink supply port tube to receive the ink withdrawal needle of an ink jet printer. A rubber O ring is provided in the ink supply port to resiliently abut against and seal against the outer periphery of the ink withdrawal needle of the printer. A step is provided in the ink supply port and the O ring abuts the downwardly facing surface of the step which prevents the ink supply needle from pushing the rubber O ring further into the ink supply port. The end of the ink supply port is sealed by a polymer film prior to use. In this way, the cartridge is sealed by the film seal against leakage of ink. When the cartridge is placed in a printer, the ink withdrawal needle of the printer will pierce the film seal and then enter the O ring which will resiliently seal against it. Thus, leakage and evaporation of ink from the cartridge through the ink supply port is prevented both before and during use.

In the known ink cartridge, liquid ink is present in the ink supply port above and within the O ring. There is a period in placement of the cartridge on the ink supply needle when the film seal has been pierced, but the needle has not gone so far as to seal against the O ring, hi that period the liquid ink in the ink supply port can flow out onto the floor of the carriage of the printer. It is also possible for the film seal to be accidentally broken, which will result in leakage of ink. The film seal is awkward to apply to the end of the ink supply port of the cartridge in manufacture.

According to a first aspect of the invention there is provided an ink cartridge for a printer, the cartridge comprising a container for holding ink and an ink supply port to receive an ink withdrawal needle of a printer, the cartridge further comprising an elastomeric member in the ink supply port to resiliently abut against and thereby seal against the outer periphery of the ink withdrawal needle in use, and a seal to seal the ink supply port and be pierced by the ink withdrawal needle, the seal being positioned in the ink supply port so that the ink withdrawal needle passes through at least part of the elastomeric member before piercing the seal.

hi this way, the seal is down in the ink supply port at least partly behind the elastomeric member and so it will not be accidentally broken. Also, the ink withdrawal needle will have been sealed against the elastomeric member before the seal is pierced and so no leakage of ink can arise.

The seal may take any suitable form and may comprise a film, such as a polymer film.

The elastomeric member may take any suitable form and preferably has a hole therethrough to receive the ink withdrawal needle of the printer. The elastomeric member may define an internal tapered guide surface to aid in centring the cartridge on the ink withdrawal needle.

The seal is preferably at least a quarter of the way down the ink supply port, more preferably at least a third of the way down and may be halfway or more down the ink supply port.

The cartridge may include an out stop to stop the elastomeric member from being pulled out of the ink supply port. The elastomeric member may be provided behind the out stop. The out stop may take any suitable form and may comprise at least one intrusion from the wall of the ink supply port. Preferably the out stop comprises an intruding rib extending inwardly from the wall of the ink supply port. The port may be made from any suitable material and may be made from plastics material. The out stop may be formed by melting the end of the ink supply port.

The cartridge may include an in stop to stop the elastomeric member from being pushed too far into the ink supply port. The in stop may take any suitable form and in one embodiment, the in stop is continuous around the ink supply port. In one embodiment, the seal is sealingly connected to the in stop. In another embodiment, the seal is mounted on a mounting piece. In a further embodiment, the seal is mounted to the elastomeric member.

According to another aspect of the invention there is provided an ink cartridge for a printer, the cartridge comprising an ink supply port to receive an ink withdrawal needle of a printer, the cartridge further including a seal to seal the ink supply port and to be pierced by the ink withdrawal needle of the printer, the seal being mounted on a mounting piece.

Mounting the seal on a mounting piece simplifies manufacture.

The mounting piece may take any suitable form and may define an aperture to receive the ink withdrawal needle. In a preferred embodiment, the mounting piece is a ring. The seal preferably seals the aperture in the mounting piece.

The mounting piece is preferably sealingly mounted to the ink supply port. The mounting piece may be mounted in any suitable way. In one embodiment, the mounting piece is mounted by press fitting. In another embodiment, the mounting piece is adhered in place and may be mounted by welding.

The mounting piece may be received in the ink supply port.

The cartridge may include locating means and the mounting piece may locate on the locating means. One of the locating means and mounting piece may define an aperture and the other of the locating means and mounting piece may define means to be received in the aperture. The locating means may define at least one gap between the locating means and the ink supply port and the mounting means may include a projection to be received in the or at least one gap. The locating means may define an outwardly facing ring within the ink supply port such that there is an annular gap between the ring and the wall of the ink supply port, and the mounting piece may define at least one projection to be received in the gap. The mounting piece may define a projecting ring to be received in the annular gap.

The cartridge may comprise a tube within the ink supply port. Ih one embodiment, the mounting piece or seal engages the end of the tube. Preferably there is a continuous web between the tube and the wall of the ink supply port, hi one embodiment, the mounting piece is connected to the web. The tube is preferably integral with the cartridge.

According to a further aspect of the invention there is provided a method in manufacture of an ink cartridge with an ink supply port, the method comprising attaching a seal to a mounting piece and mounting the mounting piece to the cartridge so that the seal seals the ink supply port.

The seal may be a film seal. The mounting piece and seal may be mounted inside the ink supply port. The mounting piece and seal may be mounted by any suitable method and may be mounted by press fitting or welding.

The method may include mounting an elastomeric member in the ink supply port to resiliently abut against and seal against the outer periphery of an ink withdrawal needle. Preferably, the elastomeric member is put into the ink supply port after the seal. The elastomeric member may be held in the ink supply port in any suitable way. In one embodiment, the end of the ink supply port is made of a meltable material such as a plastics material and is melted after insertion of the elastomeric member to form a flange overlapping the end opening of the ink supply port.

According to another aspect of the invention there is provided a method in manufacture of an ink cartridge with an ink supply port, the method comprising inserting an elastomeric member into the ink supply port and then melting the end of the ink supply port. According to a further aspect of the invention there is provided a set of parts for an ink cartridge, the set of parts comprising a first part comprising an ink tank with an ink supply port to receive an ink withdrawal needle of a printer, the set further comprising a second part comprising a mounting piece mounting a seal, the seal being capable of being pierced by the ink withdrawal needle of a printer, the set being such that when the second part is mounted to the first part, the seal seals the ink supply port.

Embodiments of the invention will now be described by way of example and with reference to the accompanying drawings, in which:

Fig 1 is a perspective view of a cartridge in accordance with the first embodiment of the invention;

Fig 2 is a side elevation of the cartridge of Fig 1 with one side removed;

Fig 3 is a detail cross-section of the ink supply port of the cartridge of Fig 1; Fig 4 is a side elevation of the cartridge in a printer, the printer being shown in fragmentary cross-section;

Fig 5 is an exploded perspective view of the elastomeric member, seal and mounting piece, and ink supply port of a cartridge in a second embodiment of the invention;

Fig 6 is the view of Fig 5 with the parts shown in cross-section; Fig 7 is a perspective view from below the ink supply port in cross-section;

Fig 8 is a perspective view from above of the ink supply port in cross-section;

Fig 9 is a detail side elevation in cross-section of the ink supply port of the cartridge of the second embodiment; and.

Figs 10 to 13 are the view of Fig 9 showing the progress of the ink withdrawal needle into the ink supply port as the cartridge is pushed into the printer.

The cartridge 10 of the first embodiment of the invention comprises an ink tank 12 and an ink supply port 14.

The ink tank 12 has two porous members 16, 17 inside which are filled with ink.

An air vent 18 is formed in the top wall 20 of the ink tank 12 and is filled by a plastic plug when the cartridge is new. The ink supply port 14 is in the form of a tube projecting downwardly from the underside 24 of the ink tank 12 of the cartridge 10. Another, shorter tube 26 is provided within the ink supply port 14 and concentric therewith. An aperture 28 into the ink tank 12 is provided at the end of the shorter tube 26 through the floor 24 of the ink tank 12.

The lower porous member 16 sits over the aperture 28.

An elastomeric packing member 30 is provided in the ink supply port 14. The elastomeric member 30 has a cylindrical outer surface and a central aperture 32 therethrough with a tapered inner surface 34.

A mounting piece 36 is also provided in the ink supply port 14. The mounting piece 36 is in the form of a ring with flat upper and lower surfaces 38, 40 and a raised outer rim 42 extending upwardly from its upper surface 38. A circular disc shaped polymer film seal 44 is adhered to the lower surface 40.

In assembly of the cartridge 10, the film seal 44 is adhered to the lower surface 40 of the mounting piece 36. This unit is then inserted into the ink supply port 14 so that the raised outer rim 42 lies in the gap 46 between the shorter tube 26 and the wall 48 of the ink supply port 14. The unit consisting of the mounting piece 36 and seal 44 is either press fitted onto the end 50 of the shorter tube 26 or placed there and ultrasonically welded onto it using a welding horn inserted into the ink supply tube 14.

The elastomeric member 30 is then placed into the ink supply port 14 onto the seal 44 so that the wide end 52 of the elastomeric member 30 is towards the outer end 54 of the ink supply port 14. The elastomeric member 30 is long enough that its lower surface 56 lies almost at the end 54 of the ink supply port 14. A heating plate is then placed against the end 54 of the ink supply port 14 to heat and melt the plastics material from which it is made so that an inwards flange 57 is formed to overlap and retain the elastomeric member 30.

On filling the cartridge with ink, ink will pass through the aperture 28 into the central hollow 58 of the shorter tube 26. The mounting piece 36 is attached to the end 50 of the shorter tube 26 such that ink cannot get past, it is a liquid tight seal. Equally, the seal film 44 is gas tight and liquid tight so that moisture and air cannot penetrate to the ink in the cartridge 10.

In use, as the cartridge 10 is placed in the carriage 62 of a printer 64, the ink withdrawal needle 60 of the printer 64 will enter the end of the ink supply tube 14 and hence will enter the wide end 52 of the elastomeric member 30. The tapered surface 34 will guide movement of the cartridge 10 to centre it on the needle 60. As the needle 60 moves further in it will resiliently abut the inner surface 34 of the elastomeric member 30 and seal therewith. As the needle 60 moves further it will touch and then pierce the film seal 44. At this point the liquid ink is able to pass the seal 44, but as the ink supply needle 60 has the elastomeric member 30 sealing against its outer periphery, the ink cannot escape and is available to be withdrawn through the hollow bore or bores in the ink withdrawal needle 60 to be transferred to the printhead of the printer 64.

As can be seen, the ink cannot escape into the cavity 66 of the printer 64 when the seal 44 is broken and so the printer 64 remains clean and uncontaminated. The seal 44 is well down inside the ink supply tube 14, about 40% of the way down inside, and is protected over much of its surface by the elastomeric member 30 and so accidental damage to the seal 44 resulting in leakage of ink is very unlikely. The use of the mounting piece 36 to mount the seal 44 makes insertion of the seal 44 much easier in the manufacturing process and indeed many mounting members 36 can be mounted to sealing film at the same time in one operation.

Figures 5 onwards show a second embodiment of the invention. The cartridge 10 of the second embodiment is similar to that of the first embodiment and only the differences from the first embodiment will be described. The same reference numerals will be used for equivalent features.

In the cartridge of the second embodiment, the shorter tube 26 within the ink supply port 14 is shorter and extends over only about a third of the axial length of the ink supply port 14, rather than about half of the length as in the first embodiment. The ink supply port 14 is about 6mm long and about 9mm in external diameter.

The elastomeric packing member 30 does not have a tapered inner surface 34. Instead, the inner surface of the elastomeric packing member 30 has an inner surface 70 which is stepped. The inner surface 70 thus consists of a first part 72 which is parallel to and concentric with the outer surface 31, and which then turns inwards through 90° towards the axis of the elastomeric packing member 30 in a second part 74, before turning parallel to the outer surface 31 again in a third part 76 defining a smaller diameter opening 78. Thus, the minimum thickness of the elastomeric packing member

30 at any point is the same.

The mounting piece 36 of the second embodiment has a raised outer rim 42 which is extended in the axial direction in comparison with the first embodiment so that the mounting piece 36 has a similar shape to the elastomeric packing member 30 but defining a larger central opening 80, and the rim 42 now forms a significant cylindrical extension 42 so that the mounting piece 36 is in fact slightly longer in the axial direction than the elastomeric packing member 30.

In the outlet port 14, itself, the annular gap between the shorter tube 26 and the wall 48 of the ink supply port 14 does not, as in the first embodiment, extend inwards to the level of the underside 24 of the ink tank 12 of the cartridge 10, but instead extends over about two thirds of the extent of the shorter tube 26 from the underside 24 of the ink tank 12.

Ih assembly of the cartridge 10, the film seal 44 is adhered to the lower surface 40 of the mounting piece 36. This unit consisting of the connected mounting piece 36 and film seal 44, is then inserted into the ink supply port 14 so that the cylindrical extension 42 lies in the gap 46 between the shorter tube and the wall 48 of the ink supply port 14, with the end 82 of the cylindrical part 42 contacting the downwardly facing surface 84 forming the upper extent of the gap 46. These two surfaces 82, 84 are then ultrasonically welded into place. It will be seen in Figure 9 for example that in the second embodiment, the upper surface 38 of the ring of the mounting piece 36 does not contact and is spaced from the end 50 of the shorter tube 26, which thus acts merely to locate the mounting piece radially with respect to the axis of the ink supply port 14. The elastomeric member 30 is then placed into the ink supply port 14 on to the seal 44 so that the wide end 52 of the elastomeric member 30 is towards the lower, outer end 54 of the ink supply port 14. The elastomeric member 30 is long enough that its lower, end surface 56 lies almost at the end 54 of the ink supply port 14. A heating plate is then placed against the end 54 of the ink supply port 14 to heat and melt the plastics material from which it is made so that an inwards flange 57 is formed to overlap and retain the elastomeric member 30.

On filling the cartridge 10 with ink, ink will pass through the aperture 28 into the central hollow 58 of the shorter tube 26. The mounting piece 36 is attached to the tank at the bottom surface 84 of the gap 46 between the shorter tube 26 and the supply port 14 such that ink cannot get past, it is a liquid tight seal. Equally, the seal 44 is liquid tight so that ink cannot escape.

In use, as the cartridge 10 is placed in the carriage 62 of a printer 64, the ink withdrawal needle of the printer 64 will enter the end of the ink supply tube 14 and hence will enter the wide end 52 of the elastomeric member 30, as shown in Figure 10. As the needle 60 moves further in, it will abut the entrance to the opening 78 as shown in Figure 11. The opening 78 is slightly smaller than the diameter of the ink supply needle 60 so that as the cartridge 10 is pushed further downwards, the elastomeric seal member 30 will be resiliently compressed and the part 76 of its inner surface will seal against the outer surface 90 of the ink withdrawal needle 60. As the cartridge 10 is pushed further down, the end of the needle 60 will touch and then pierce the film seal 44 as shown in Figure 12. The seal 44 is now broken, but ink cannot escape because the ink supply needle 60 has the elastomeric member 30 sealing against its outer surface 90. Figure 13 shows the cartridge fully inserted into the printer carriage 62 with the end of the ink withdrawal needle 60 within the central hollow 58 of the shorter tube 26.

Claims

1. An ink cartridge for a printer, the cartridge comprising a container for holding ink and an ink supply port to receive an ink withdrawal needle of a printer, the cartridge further comprising an elastomeric member in the ink supply port to resiliently abut against and thereby seal against the outer periphery of the ink withdrawal needle in use, and a seal to seal the ink supply port and be pierced by the ink withdrawal needle, the seal being positioned in the ink supply port so that the ink withdrawal needle passes through at least part of the elastomeric member before piercing the seal.

2. An ink cartridge as claimed in claim 1, wherein the seal comprises a film.

3. An ink cartridge as claimed in claim 2, wherein the seal comprises a polymer film.

4. An ink cartridge as claimed in claim 1, 2 or 3, wherein the elastomeric member has a hole therethrough to receive the ink withdrawal needle of the printer.

5. An ink cartridge as claimed in claim 4, wherein the elastomeric member defines an internal tapered guide surface to aid in centring the cartridge on the ink withdrawal needle.

6. An ink cartridge as claimed in any preceding claim, wherein the seal is at least a quarter of the way down the ink supply port.

7. An ink cartridge as claimed in any preceding claim, wherein the seal is at least a third of the way down the ink supply port.

8. An ink cartridge as claimed in any preceding claim, wherein the seal is halfway or more down the ink supply port.

9. An ink cartridge as claimed in any preceding claim, wherein the cartridge includes an out stop to stop the elastomeric member from being pulled out of the ink supply port.

10. An ink cartridge as claimed in claim 9, wherein the elastomeric member is provided behind the out stop.

11. An ink cartridge as claimed in claim 9 or claim 10, wherein the out stop comprises at least one intrusion from the wall of the ink supply port.

12. An ink cartridge as claimed in claim 11, wherein the out stop comprises an intruding rib extending inwardly from the wall of the ink supply port.

13. An ink cartridge as claimed in any preceding claim, wherein the port is made from plastics material.

14. An ink cartridge as claimed in claim 13, when dependent upon any of claims 8 to 12, wherein the out stop is formed by melting the end of the ink supply port.

15. An ink cartridge as claimed in any preceding claim, wherein the cartridge includes an in stop to stop the elastomeric member from being pushed too far into the ink supply port.

16. An ink cartridge as claimed in claim 15, wherein the in stop is continuous around the ink supply port.

17. An ink cartridge for a printer, the cartridge comprising an ink supply port to receive an ink withdrawal needle of a printer, the cartridge further including a seal to seal the ink supply port and to be pierced by the ink withdrawal needle of the printer, the seal being mounted on a mounting piece.

18. An ink cartridge as claimed in claim 17, wherein the mounting piece defines an aperture to receive the ink withdrawal needle.

19. An ink cartridge as claimed in claim 18, wherein the mounting piece is a ring.

20. An ink cartridge as claimed in claim 18 or 19, wherein the seal seals the aperture in the mounting piece.

21. An ink cartridge as claimed in any of claims 17 to 20, wherein the seal comprises a film.

22. An ink cartridge as claimed in claim 21, wherein the seal is a polymer film.

23. An ink cartridge as claimed in any of claims 17 to 22, wherein the mounting piece is sealingly mounted to the ink supply port.

24. An ink cartridge as claimed in claim 23, wherein the mounting piece is mounted by welding.

25. An ink cartridge as claimed in any of claims 17 to 24, wherein the mounting piece is received in the ink supply port.

26. An ink cartridge as claimed in any of claims 17 to 25, wherein the cartridge includes locating means and the mounting piece locates on the locating means.

27. An ink cartridge as claimed in claim 26, wherein one of the locating means and mounting piece defines an aperture and the other of the locating means and mounting piece defines means to be received in the aperture.

28. An ink cartridge as claimed in claim 26 or claim 27, wherein the locating means defines at least one gap between the locating means and the ink supply port and the mounting means includes a projection to be received in the or at least one gap.

29. An ink cartridge as claimed in claim 28, wherein the locating means defines an outwardly facing ring within the ink supply port such that there is an annular gap between the ring and the wall of the ink supply port, and the mounting piece defines at least one projection to be received in the gap.

30. An ink cartridge as claimed in claim 29, wherein the mounting piece defines a projecting ring to be received in the annular gap.

31. An ink cartridge as claimed in any of claims 17 to 30, wherein the cartridge comprises a tube within the ink supply port.

32. An ink cartridge as claimed in claim 31, wherein the mounting piece or seal engages the end of the tube.

33. An ink cartridge as claimed in claim 31 or 32, wherein there is a continuous web between the tube and the wall of the ink supply port.

34. An ink cartridge as claimed in claim 33, wherein the mounting piece is connected to the web.

35. An ink cartridge as claimed in any of claims 31 to 34, wherein the tube is integral with the cartridge.

36. A method in manufacture of an ink cartridge with an ink supply port, the method comprising attaching a seal to a mounting piece and mounting the mounting piece to the cartridge so that the seal seals the ink supply port.

37. A method as claimed in claim 36, wherein the seal is a film seal.

38. A method as claimed in claim 36 or claim 37, wherein the mounting piece and seal are mounted inside the ink supply port.

39. A method as claimed in claim 36, 37 or 38, wherein the mounting piece and seal are mounted by welding.

40. A method as claimed in any of claims 36 to 39, wherein the method includes mounting an elastomeric member in the ink supply port to resiliently abut against and seal against the outer periphery of an ink withdrawal needle.

41. A method as claimed in claim 40, wherein the elastomeric member is put into the ink supply port after the seal.

42. A method as claimed in any of claims 36 to 41, wherein the end of the ink supply port is made of a meltable material, such as a plastics material, and is melted after insertion of the elastomeric member to form a flange overlapping the end opening of the ink supply port.

43. A method in manufacture of an ink cartridge with an ink supply port, the method comprising inserting an elastomeric member into the ink supply port and then melting the end of the ink supply port.

44. A set of parts for an ink cartridge, the set of parts comprising a first part comprising an ink tank with an ink supply port to receive an ink withdrawal needle of a printer, the set further comprising a second part comprising a mounting piece mounting a seal, the seal being capable of being pierced by the ink withdrawal needle of a printer, the set being such that when the second part is mounted to the first part, the seal seals the ink supply port.