GB2424620A

GB2424620A - Ink cartridge having a pressure regulator

Info

Publication number: GB2424620A
Application number: GB0506409A
Authority: GB
Inventors: Pui-Kuong Lui
Original assignee: Monitek Electronics Ltd
Current assignee: Monitek Electronics Ltd
Priority date: 2005-03-30
Filing date: 2005-03-30
Publication date: 2006-10-04
Anticipated expiration: 2025-03-30
Also published as: GB2424620B; GB0506409D0

Abstract

An ink cartridge includes a hollow ink tank body (1), a cover member (2) connected to the hollow ink tank body, a tube (3) and a pressure regulator (4) arranged inside the hollow ink tank body. The cover member has an air vent (21) penetrating therethrough, and a first through-hole protrusion (22) adjacent to the air vent and extending towards the hollow ink tank body. The pressure regulator includes a holder (41), a resilient member (42) arranged inside the holder, an elastic plate (43) connected to the resilient member and abutting against the holder, a securing member (44) disposed over the elastic plate, and a thin film (445) covering the securing member. The pressure regulator further has a through-hole projection (45) extending outwardly therefrom for connecting to the tube that connects to the first through-hole protrusion (412) of the cover, so that the atmospheric air passes through the pressure regulator via the tube after a sealing film (5) is removed.

Description

INK CARTRIDGE

The present invention relates to an ink cartridge adapted for an ink jet printer, and particularly relates to an ink cartridge that can ameliorate ink leakage problems at both the inlet and outlet of the ink cartridge.

Ink jet recording technology enables characters and images to be printed directly on a recording medium (such as paper, cloth, or plastic sheet) by discharging ink from fine nozzles thereto. Conventionally, such printing apparatus has been implemented as a printer serving and provided as the output terminal of a copying machine, a facsimile machine, a printer, a word processor, a work station or the like; or as a handy or portable printer used for such information processing systems as a personal computer, a host computer, an optical disc device or a video apparatus. In a conventional printing apparatus, ink is supplied to a recording head from an ink tank constructed as a cartridge.

Although ink can be prevented from seeping out of the recording head by applying a negative pressure, the negative pressure has an upper limit. If the negative pressure is too high, ink cannot overcome the negative pressure and jet from the recording head. On the other hand, the ink cartridge must be able to adjust the negative pressure in the ink tank automatically by keeping the negative pressure within a suitable range. U. S. Pat. No. 6,783,219 B2, entitled "Ink Cartridge", discloses an elastic member for unidirectional ventilation by a pressure difference between the interior and exterior of the hollow ink tank body without an air inlet hole and porous member. A pressure regulator referred in the prior art is used to maintain the pressure and the ink flows to the printhead continuously. Nevertheless, ink leakage problems of the pressure regulator may occur during storage, delivery and printing. Alternative pressure regulators have been explored but have failed to adequately address the leakage issue.

It is desirable to develop a new and improved ink cartridge to ameliorate or substantially resolve the above leakage problems and provide better, more advantageous overall results.

The present invention is defined in the independent claims.

In one embodiment the ink cartridge is provided with a pressure regulator arranged inside the ink cartridge (i.e. in the ink reservoir thereof) and communicating with the atmospheric air via an upper air vent formed on a cover and a tube connected to the air vent, so that the atmospheric air communicates with the interior of the cartridge effectively during printing.

is The ink cartridge of this embodiment is provided with an ink supply assembly that has a small bell-shaped plug with a center slot and a resilient member locked to the plug, so that the ink supply assembly is secured elastically and prevents the ink from leaking out easily from the ink supply assembly.

In a preferred embodiment the ink cartridge includes a hollow ink tank body, a cover member, a hollow tube and a pressure regulator. The hollow ink tank body defines a cavity therein and an outlet port formed on a bottom thereof. The cover member is connected to a top of the hollow ink tank body; and has an air vent penetrating therethrough, and a first through-hole protrusion adjacent to the air vent and communicating with the cavity (reservoir) of the hollow ink tank body. The hollow tube is connected to the first through-hole protrusion of the cover. The pressure regulator is arranged inside the cavity of the hollow ink tank body and connected to the hollow tube. The pressure regulator includes a holder, a resilient member arranged inside the holder, an elastic plate connected to the resilient member and abutting against the holder, a securing member disposed over the elastic plate, and a thin film covering the securing member. The pressure regulator further has a through-hole projection extending outwardly from the holder and securing member assembly for communicating with the inside of the holder and connecting to the hollow tube, so that the atmospheric air passes through the pressure regulator via the hollow tube after a sealing film is removed.

Preferred embodiments of the invention are described below by way of example only with reference to Figures 1 to 6 of the accompanying drawings, wherein: Fig. 1 is an exploded view of an ink cartridge according to the present invention; Fig. 2 is an exploded view of a pressure regulator of the ink cartridge; Fig. 2A is a cross-sectional profile of the pressure regulator of the ink cartridge; Fig. 2B is a cross-sectional profile of a variant of the pressure regulator of the ink cartridge; Fig. 2C is a cross-sectional profile of a further variant of the pressure regulator of the ink cartridge; Fig. 2D is a cross-sectional profile of a further variant of the pressure regulator of the ink cartridge; Fig. 3 is an exploded view of the pressure regulator of another embodiment of the ink cartridge; Fig. 4 is an enlarged view of a bell-shaped plug of an ink supply assembly of the ink cartridge of Fig. 1; Fig. 5 is an enlarged view of a through-hole insert of the ink supply assembly of the ink cartridge of Fig. 1; Fig. 6 is an exploded view of another embodiment of the ink cartridge.

Referring to Fig. 1, an ink cartridge according to an embodiment of the present invention includes a hollow ink tank body 1, a cover member 2, a tube 3, a pressure regulator 4, a sealing film 5 enclosing the cover member 2, and an ink supply assembly 6. The hollow ink tank body 1 defines a cavity 10 therein for filling with ink and an outlet port 11 formed on a bottom thereof for delivering the ink outwards. The cover member 2 is connected to a top of the hollow ink tank body 1; and has an air vent 21 penetrating therethrough, and a first through-hole protrusion 22 adjacent to the air vent 21 and extending forwards the cavity 10 of the hollow ink tank body 1. The sealing film 5 seals the air vent 21 of the cover member 2 before use. The tube 3 is connected to the first through-hole protrusion 22 of the cover member 2 via an end thereof.

In addition, the tube 3 can be made of flexible or rigid materials, so that the tube 3 disposed in the cavity 10 of the hollow ink tank body 1 can be curved or straight.

The pressure regulator 4 is arranged inside the cavity 10 of the hollow ink tank body 1 and connected to an opposite end of the tube 3. Illustrated in Figs. 2 and 2A, the pressure regulator 4 includes a holder 41, a resilient member 42 arranged inside the holder 41, an elastic plate 43 connected to the resilient member 42 and abutting against the holder 41, a securing member 44 disposed over the elastic plate 43, and a thin film 45 covering the secure member 44.

The holder 41 includes a peripheral wall 410, a bottom wall 411 connected with the peripheral wall 410, a first through-hole projection 412 extending outwardly from the peripheral wall 410 thereof and communicating with an inside 413 thereof, and an annular partition wall 414 disposed on the bottom wall 411 and adjacent to but spaced apart from the peripheral wall 410 for engaging a circular flange 431 of the elastic plate 43 in the annular gap therebetween. The first through-hole projection 412 connects to the tube 3 so that the atmospheric air passes through the pressure regulator 4 via the tube 3 I 5 after the sealing film 5 is removed. The holder 41 further includes a plurality of apertures 415 in its outer wall communicating with the pressure regulator 4 and the cavity 10 of the hollow ink tank body 1.

Illustrated in Fig. 2A, the holder 41 can define a recess 416 formed on the bottom wall 411 and a hole 4160 penetrating the bottom wall 411. The hole 4160 corresponds to the recess 416 for communicating with the pressure regulator 4 and the cavity 10 of the hollow ink tank body 1. An end of the resilient member 42 can be located in the recess 416 for orientation and another end of that is fitted with a protrusion 432 of the elastic plate 43.

Illustrated in Fig. 2B, the holder 41 can define an annular recess 416' formed on the bottom wall 411 and a hole 4160' penetrating the bottom wall 411. The hole 4160' corresponds to the annular recess 416' for communicating with the pressure regulator 4 and the cavity 10 of the hollow ink tank body 1.

An end of the resilient member 42 can be located inside the annular recess 416' for orientation.

In another embodiment, the holder 41, illustrated in Fig. 2C includes a second through-hole protrusion 417 extending from the bottom wall 411 upwardly and a hole 4170 penetrating the bottom wall 411. The hole 4170 corresponds to the second through-hole protrusion 417 for communicating with the pressure regulator 4 and the cavity 10 of the hollow ink tank body 1. An end of the resilient member 42 can be sleeved on the second through-hole protrusion 417.

In a further embodiment, the holder 41, illustrated in Fig. 2D according to the present invention, has a solid pillar 417' extending from the bottom wall 411 upwardly so that the resilient member 41 is sleeved on the pillar 417'. The resilient member 42 can be a compression spring that has two ends connected to the holder 41 and the elastic plate 43 respectively. In other embodiments of the resilient member 42 need not be so restricted. The elastic plate 43 of the pressure regulator 4 includes a plate body 430, the flange 431 disposed circumferentially on the plate body 430 and engaged with the partition wall 414 and the peripheral wall 410 of the holder 41, the protrusion 432 aligned and sleeved with the resilient member 42, and a circular concave portion 433 arranged between the protrusion 432 thereof and the partition wall 414 of the holder 41. The securing member 44 includes a securing body 440, a plurality of apertures 441 in the securing body 440, a plurality of projections 442 extending radially outwardly from the periphery of the securing body 440 in order to retain it against the peripheral wall 410 of the holder 41, and a supporting wall 443 extending from the secure body 440 downwardly to abut against the elastic plate 43. Particularly, the supporting wall 443 abuts against the plate body 430 and locates between the circular concave portion 433 and the flange 431. The securing member 44 further includes a land 444 disposed centrally on a lower surface of the securing body 440 and aligned with the resilient member 42 but spaced a predetermined distance "d" from the elastic plate 43. The land 444 is used for stopping the elastic plate 43 from rising upwards too far due to the resilient member 42, and the predetermined distance "d" provides a space for stretching the resilient member 42. The thin film 45 is used to bond the secure member 44 and the holder 41 together, and to cover on the secure body 440 of the secure member 44.

Another embodiment with differences in both the holder 41 and the securing member 44 is illustrated in Fig. 3. The holder 41 includes the peripheral wall 410, the bottom wall 411 connected with the peripheral wall 410, a channel-shaped opening 418 formed on the peripheral wall 410, the cavity enclosed by the peripheral wall 410 and the bottom wall 411, and the partition wall 414 disposed annularly on the bottom wall 411 and adjacent to the peripheral wall 410. The securing member 44 includes the securing body 440, the apertures 441 in the securing body 440, the projections 442 extending radially outwardly from the periphery of the securing body 440 in order to retain it against the peripheral wall 410 of the holder 41, the supporting wall 443 extending from the securing body 440 downwardly to abut against the elastic plate 43, and a second through-hole projection 445 extending outwardly from the securing body 440 thereof. The land (not shown) is still disposed on the lower surface of the securing body 440. The second through-hole projection 445 corresponds to the channel-shaped opening 418 of the holder 41 and projects from the holder 41 and rests in the channel- shaped opening 418.

With reference to Figs. 1, 4 and 5, the ink supply assembly 6 is disposed on the outlet port 11 of the hollow ink tank body 10. The ink supply assembly 6 includes an outlet resilient member 61, a bell-shaped plug 62 sleeved with the outlet resilient member 61, a through-hole insert 63 disposed under the plug 61, and an outlet sealing film 64 covering the through-hole insert 63. The bell- shaped plug 62 has a plug plate 620, two upright walls 621 disposed on the plug plate 620 and opposite to each other, a slot 622 formed between the two upright walls 621 and a vent 623 formed on the plug plate 620 for communicating with the through-hole insert 63. Each of the two upright walls 621 has a bell-shaped projection 6210 disposed thereto to retain against the outlet resilient member 61 for resiliently securing the ink supply assembly 6.

The vent 623 formed on the plug plate 620 is one part of the ink delivery path.

The sealing film 64 can close the through-hole insert 63, and the throughhole insert 63 includes a flange 631 for engaging with the outlet port 11 of the hollow ink tank body 1. Therefore, the ink leakage of the ink supply assembly 6 can be prevented easily.

Referring to Fig. 1, the pressure regulator 4 is disposed in the cavity 10 of the hollow ink tank body 1 in a vertical manner and can be attached on a side inner wall of the hollow ink tank body 1. Alternatively, the pressure regulator 4 is disposed in the cavity 10 of the hollow ink tank body 1 in a horizontal maimer as illustrated in Fig. 6 and can be attached to the bottom surface of the cover member 2.

In preferred embodiments of the present invention, the advantages of the ink cartridge are as follows: 1. An ink cartridge adapted for an ink jet printer is provided for preventing io ink leakage problems at both the inlet and outlet of the ink cartridge.

2. The ink cartridge is provided with a pressure regulator arranged inside the ink cartridge and communicating with the atmospheric air via an upper air vent formed on a cover and a hollow tube connecting the air vent, so that the atmospheric air communicates with internal cartridge effectively while printing.

3. The ink cartridge is provided with an ink supply assembly that has a small bell-shaped plug with a center slot and a resilient member locked to the plug, so that the ink supply assembly is secured resiliently and prevents the ink from leaking out of the ink supply assembly easily.

4. The ink cartridge provides an alternative air ventilation method to ameliorate the ink leakage problem during delivery, storage or printing operation. During printing, the ink flows out of a supply port and the air will then flow into the hollow ink tank body from the regulator to compensate the negative pressure inside the ink cartridge.

It should be apparent to those skilled in the art that the above description is only illustrative of specific embodiments and examples of the invention.

The invention is applicable to multi-colour ink cartridges as well as simple colour (black) ink cartridges.

Claims

CLAIMS: 1. An ink cartridge comprising: a hollow ink tank body defining a

cavity therein, and an outlet port formed on a bottom thereof; a cover member connected to a top of the hollow ink tank body; wherein the cover has an air vent penetrating therethrough, and a first through-hole protrusion adjacent to the air vent and communicating with the cavity of the hollow ink tank body; a tube connected to the first through-hole protrusion of the cover; and a pressure regulator arranged inside the cavity of the hollow ink tank body and connected to the hollow tube; wherein the pressure regulator includes a holder, a resilient member arranged inside the holder, an elastic plate connected to the resilient member and abutting against the holder, a securing member disposed over the elastic plate, and a thin film covering the securing member; wherein the pressure regulator further includes a through-hole projection extending outwardly from the holder and securing member assembly for communicating with the interior of the holder and connecting with the tube, so that in use, atmospheric air passes through the pressure regulator via the hollow tube after an external sealing film is removed.
2. The ink cartridge as claimed in claim 1, wherein the holder of the pressure regulator includes a peripheral wall, a bottom wall connected with the peripheral wall, and a partition wall disposed annularly on the bottom wall and adjacent to the peripheral wall for engaging a circular flange of the elastic plate therebetween.
3. The ink cartridge as claimed in claim 2, wherein the holder of the pressure regulator has a plurality of apertures therein for communicating with the pressure regulator and the cavity of the hollow ink tank body.
4. The ink cartridge as claimed in claim 2 or claim 3, wherein the holder of the pressure regulator has a recess, optionally an annular recess formed therein for receiving the resilient member.
5. The ink cartridge as claimed in any of claims 2 to 4, wherein the through- hole projection extends outwardly from the peripheral wall of the holder.
6. The ink cartridge as claimed in any of claims 2 to 5, wherein the holder of the pressure regulator has a second through-hole protrusion extending from the bottom wall upwardly, the resilient member is sleeved on the second through- hole protrusion and capable of communicating with the cavity of the hollow ink tank body; alternatively, the holder of the pressure regulator has a solid pillar is extending from the bottom wall upwardly, and the resilient member is sleeved on the solid pillar.
7. The ink cartridge as claimed in any of claims 2 to 6, wherein the elastic plate of the pressure regulator includes a protrusion aligned with and sleeved with the resilient member.
8. The ink cartridge as claimed in claim 7, wherein the elastic plate of the pressure regulator includes a circular concave portion arranged between the protrusion thereof and the partition wall of the holder.
9. The ink cartridge as claimed in any of claims 2 to 8, wherein the securing member includes a plurality of apertures therein and a plurality of projections extending radially outwardly from the periphery thereof in order to retain it against the peripheral wall of the holder.
10. The ink cartridge as claimed in any of claims 2 to 9, wherein the securing member includes a supporting wall extending therefrom downwardly to abut against the elastic plate.
11. The ink cartridge as claimed in any of claims 2 to 10, wherein the securing member includes a land disposed on a lower surface thereof and aligned with the resilient member.
12. The ink cartridge as claimed in any of claims 2 to 11, wherein the peripheral wall of the holder has a concave opening, the through-hole projection extends outwardly from the securing member and is aligned with the concave opening, and the through-hole projection protrudes from the peripheral wall of the holder to the concave opening.
13. The ink cartridge as claimed in any preceding claim, further including an ink supply assembly at the outlet port of the hollow ink tank body, wherein the ink supply assembly includes an outlet resilient member, a plug having an expanded end sleeved with the outlet resilient member, a through-hole insert member disposed under the plug, and an outlet sealing film covered the through-hole insert member.
14. The ink cartridge as claimed in claim 13, wherein the bell-shaped plug has a plug plate, two upright walls disposed on the plug plate and opposite to each other, a slot formed between the two upright walls, and a vent formed on the plug plate for communicating with the through-hole insert member.
15. The ink cartridge as claimed in claim 14, wherein each of the two upright walls has an expanded end region engaging the outlet resilient member for resiliently securing the ink supply assembly.
16. The ink cartridge as claimed in any preceding claim, wherein the tube is flexible.
17. The ink cartridge as claimed in any preceding claim, wherein the tube is rigid.
18. The ink cartridge as claimed in any preceding claim, wherein the pressure regulator is disposed vertically in the cavity of the hollow ink tank body.
19. The ink cartridge as claimed in any preceding claim, wherein the pressure regulator is disposed horizontally in the cavity of the hollow ink tank body.
20.An ink cartridge substantially as described hereinabove with reference to: Figs. 1, 2, 2A, 4 and 5 optionally as modified in accordance with any of Figs. 2B, 2C, 2D, 3 or 6 of the accompanying drawings. (((C (C C &

20. An ink cartridge for an ink jet printer, the ink cartridge having a pressure regulator disposed in the ink reservoir thereof, said pressure regulator having an inlet port communicating with an air vent and an outlet communicating with the ink reservoir.

21. An ink cartridge substantially as described hereinabove with reference to Figs. 1, 2, 2A, 4 and 5 optionally as modified in accordance with any of Figs. 2B, 2C, 2D, 3 or 6 of the accompanying drawings.

Amendments to the claims have been filed as follows CLAIMS: 1. An ink cartridge comprising: a hollow ink tank body defining a cavity therein, and an outlet port formed on a bottom thereof; a cover member connected to a top of the hollow ink tank body; wherein the cover has an air vent penetrating therethrough, and a first through-hole protrusion adjacent to the air vent and communicating with the cavity of the hollow ink tank body; a tube connected to the first through-hole protrusion of the cover; and a pressure regulator arranged inside the cavity of the hollow ink tank body and connected to the tube; wherein the pressure regulator includes a holder, a resilient member arranged inside the holder, an elastic plate connected to the resilient member and abutting against the holder, a securing member disposed over the elastic plate, and a thin film covering the securing member; wherein the pressure regulator further includes a through-hole projection extending outwardly from the holder and securing member assembly for communicating with the interior of the holder and connecting with the tube, so that in use, atmospheric air passes through the pressure regulator via the tube after an external sealing film is removed.

2. The ink cartridge as claimed in claim 1, wherein the holder of the pressure regulator includes a peripheral wall, a bottom wall connected with the peripheral wall, and a partition wall disposed annularly on the bottom wall and adjacent to the peripheral wall for engaging a circular flange of the elastic plate therebetween.

3. The ink cartridge as claimed in claim 2, wherein the holder of the pressure regulator has a plurality of apertures therein for communicating with the pressure regulator and the cavity of the hollow ink tank body.

4. The ink cartridge as claimed in claim 2 or claim 3, wherein the holder of the pressure regulator has a recess, optionally an annular recess formed therein for receiving the resilient member.

5. The ink cartridge as claimed in any of claims 2 to 4, wherein the through- hole projection extends outwardly from the peripheral wall of the holder.

6. The ink cartridge as claimed in any of claims 2 to 5, wherein the holder of the pressure regulator has a solid pillar or a second throughhole protrusion extending upwardly from the bottom wall, the resilient member is sleeved on the solid pillar or second through-hole protrusion and, if sleeved on the second through-hole protrusion, is capable of communicating with the cavity of the hollow ink tank body.

7. The ink cartridge as claimed in any of claims 2 to 6, wherein the elastic plate of the pressure regulator includes a protrusion aligned with and sleeved with the resilient member.

8.The ink cartridge as claimed in claim 7, wherein the elastic plate of the pressure regulator includes a circular concave portion arranged between the protrusion thereof and the partition wall of the holder.

9.The ink cartridge as claimed in any of claims 2 to 8, wherein the securing member includes a plurality of apertures therein and a plurality of projections extending radially outwardly from the periphery thereof in order to retain it against the peripheral wall of the holder.

10.The ink cartridge as claimed in any of claims 2 to 9, wherein the securing member includes a supporting wall extending therefrom downwardly to abut against the elastic plate.

11.The ink cartridge as claimed in any of claims 2 to 10, wherein the securing member includes a land disposed on a lower surface thereof and aligned with the resilient member.

1 2.The ink cartridge as claimed in any of claims 2 to 11, wherein the peripheral wall of the holder has a channel-shaped opening, the throughhole projection extends outwardly from the securing member and is aligned with the channel- shaped opening, and the through-hole projection protrudes from the peripheral wall of the holder through the channel-shaped opening. C 13.The ink cartridge as claimed in any preceding claim, further including an ink supply assembly at the outlet port of the hollow ink tank body, wherein the : ink supply assembly includes an outlet resilient member, a plug having an expanded end sleeved with the outlet resilient member, a through-hole insert member disposed under the plug, and an outlet sealing film covered the through-hole insert member.

14.The ink cartridge as claimed in claim 13, wherein the plug has a plug plate, two upright walls disposed on the plug plate and opposite to each other, a slot formed between the two upright walls, and a vent formed on the plug plate for communicating with the through-hole insert member.

15.The ink cartridge as claimed in claim 14, wherein each of the two upright walls has an expanded end region engaging the outlet resilient member for 1? resiliently securing the ink supply assembly.

1 6.The ink cartridge as claimed in any preceding claim, wherein the tube is flexible.

17.The ink cartridge as claimed in any preceding claim, wherein the tube is rigid.

I 8.The ink cartridge as claimed in any preceding claim, wherein the pressure regulator is disposed vertically in the cavity of the hollow ink tank body.

I 9.The ink cartridge as claimed in any preceding claim, wherein the pressure regulator is disposed horizontally in the cavity of the hollow ink tank body.