WO1998003339A1

WO1998003339A1 - Holder for refilling of an ink jet printhead and creating a depression therein

Info

Publication number: WO1998003339A1
Application number: PCT/IT1997/000155
Authority: WO
Inventors: Giorgio Solero
Original assignee: Olivetti Lexikon S.P.A.
Priority date: 1996-07-19
Filing date: 1997-06-30
Publication date: 1998-01-29
Also published as: IT1284684B1; ITTO960628A1

Abstract

A holder (10) for refilling an ink jet printhead (11) and provided with an ink tank, comprises a bottom part (12) suitable for accommodating the printhead (11), a cover (13) suitable for being overlaid on the bottom part (12), and positioning means (31, 32) supported by the cover (13) to enable positioning of a refill cartridge (33) with respect to the printhead (11) accommodated in the bottom part (12). The bottom part (12) bears two fulcrum-mounted handles (17, 18) provided with two respective cams (22, 23) which, when the handles are turned and closed with respect to the bottom part (12), press against resiliently yielding walls (57, 58) of the printhead (11) accommodated in the bottom part (12), deforming them and causing a corresponding reduction in volume of the ink tank. Accordingly, when the handles (17, 18) are opened again, on completion of refilling, and the associated cams (22, 23) are disengaged from the yielding walls, the ink tank automatically expands and enters a state of depression.

Description

HOLDER FOR REFILLING OF AN INK JET PRINTHEAD AND CREATING A

DEPRESSION THEREIN

FIELD OF THE INVENTION This invention relates to a holder for refilling of an ink jet pπnthead and

particularly a holder of the type comprising a bottom part suitable for accommodating the printhead, a cover suitable for being overlaid on the bottom part, and positioning means supported by the cover and suitable for positioning

a refill cartridge with respect to the pnnthead accommodated in the bottom part,

thereby permitting refilling of a tank of ink in the printhead BACKGROUND OF THE INVENTION

Various holders of the type described above have been developed,

generally with the object of facilitating the refilling operation.

One such device is described in the international patent application in the name of the Applicant and published on May 1 , 1997 with N° W097/15449 This device, though it has the advantage of making the printhead

refilling operation very convenient, does not tackle the problem of eliminating

possible dripping, after refilling is completed, of the ink from the nozzles in the head, and particularly the dripping caused by non-optimal pressure conditions

of the ink tank in the printhead.

It is in fact known that, for optimum performance, many of the currently marketed ink jet pπntheads such as, for example, the HP51640A head

produced by the Hewlett-Packard company, manufacturing details of which are

described in US patent application no. 5,280,300, require their ink tank to be maintained at a slight depression with respect to the surrounding environment, so as to avoid ink from being drawn from the nozzles and giving rise to drips. It

is clear that this condition of depression should be maintained, even after completion of refilling of printheads of this type with ink.

Unfortunately, however, working of the holder cited above completely

overlooks this requirement, simply refilling the printhead with ink without

attempting to control the depression that the tank of the printhead should be provided with.

SUMMARY OF THE INVENTION

The technical problem that this holder intends to solve is that of

providing a holder which, in addition to enabling convenient refilling of an ink jet printhead, is also suitable for ensuring that the associated ink tank remains in a given depression following refilling, as is required for optimum operation of

the printhead.

This problem is solved by the holder according to this invention, which is suitable for use with a printhead having resiliently yielding walls associated

with the ink tank of the printhead so that the volume of the tank varies in

relation to yielding of the walls, and is characterized by the fact that the bottom

part comprises mechanical deforming means for resiliently deforming the yielding walls of the printhead, and that the deforming means are suitable for

selectively assuming a working position wherein they engage with the walls to

reduce volume of the tank, and an idle position wherein they are disengaged

from the said walls. BRIEF DESCRIPTION OF THE DRAWINGS This and other characteristics of the present invention will be clear from the description that follows, provided by way of non-exhaustive example, with

reference to the accompanying drawings, where:

Fig. 1 is a lateral view of a holder for refilling of a ink jet printhead according to this invention;

Fig. 2 is a view from above of the holder of Fig. 1 , with an ink jet printhead

accommodated inside;

Fig. 3 is a lateral, partial section, along the line Ill-Ill of Fig. 2; and Fig. 4 is a front, partial section, along the line IV-IV of Fig. 3.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

With reference to Figs. 1 and 3, a holder 10 for refilling an ink jet

printhead 11 by means of a refill cartridge 33, comprises a bottom part 12 suitable for accommodating the head 11 , and a cover 13, suitable for being

overlaid on the bottom part 12 and fulcrum-mounted on the latter 12 by means

of a hinge 14.

The head 11 is ink jet type and comprises internally an ink tank, not

shown in the drawings, a plurality of nozzles 52 arranged on an external face of

the head 11 , and a refill hole 53, normally closed by a sealing element 54 in the

shape of a ball. The refill hole 53 is provided to enable feeding of the tank with

ink. The tank is of variable volume and is associated with resiliently yielding, lateral walls 57, 58 of the pπnthead 11 , in such a way that a depression of the

latter correspondingly produces a depression of the tank and a notable

reduction of inner volume of the latter-named. The printhead 11 is intended to be coupled with a protective cap 56 suitable for fitting on the portion of the

head 11 bearing the nozzles 52, in order to hermetically seal the latter,

particularly when the printhead 11 is accommodated in the bottom part 12 for refilling with ink, as described later. Generally speaking, the purpose of the protective cap 56 is to protect and seal the nozzles 52 of the printhead 11 ,

whenever the latter is not fitted in a printer for use therewith and, in keeping

with this purpose, the cap 56 may also be used to protect the nozzles 52 when the head is not inserted in the holder 10. Further details of internal make-up of the printhead 11 may be had from previously cited US patent application no.

5,280,300.

The bottom part 12 has a substantially parallelepiped shape and

internally defines a space 16 suitable for receiving and positioning the printhead 11. According to one characteristic of the invention, on the bottom

part 12, in correspondence with two lateral sides 21 , two handles 17 and 18 are fulcrum-mounted and, if rotated with respect to the bottom part 12, are suitable for creating pressure on the yielding walls 57 and 58 respectively of the

printhead 11 , when the latter is accommodated in the said bottom part 12.

The handles 17, 18 each have a manually actuatable end protruding from a corresponding aperture 19, made in each lateral side 21 of the bottom part 12.

Furthermore each handle 17, 18 is made integral with a cam 22 and 23

respectively, which are housed inside secondary spaces 24 in the bottom part

12 adjacent to the space 16. The cams 22 and 23 have a substantially cylindrical surface, arranged slightly eccentrically with respect to the pivoting

axis of the respective handles 17 and 18. The latter-named are suitable for rotation downwards, starting from a working position (indicated with an unbroken line in Fig. 4) wherein the cams 22 and 23 are disengaged from the walls 57 and 58, to reach a working position (indicated with a dash-and-dot

line) wherein the cams 22 and 23 exit from their respective spaces 24 and

extend partly into the space 16.

The cover 13 is provided with a tab 34 for manual actuation thereof and

slidingly supports a sliding element 31 , fastened to which is a short pipe 32

having two opposite ends, of which a first end 59 is suitable for cooperation

with a sealing element 54, when the printhead is accommodated in the bottom part 12 and the cover 13 is overlaid on the latter, and a second end 60 is

suitable for perforating the tip of the refill cartridge 33.

The sliding element 31 and its method of operation have been described

in the international patent application N° W097/15449 above cited, to which reference should be made for any construction details not described herein.

At one extremity of its sliding stroke with respect to the cover 13, the

sliding element 31 assumes a corresponding end-of-stroke position, in which the sliding element 31 rests against the cover 13 and becomes integral

therewith. Further, when the sliding element 31 is in this end-of-stroke position

and the cover 13 is overlaid on the bottom part 12, the first end 59 of the tube

32 is arranged above the hole 53, at a predetermined distance from the latter corresponding to the diameter of the ball sealing element 54, or rather to the axial dimensions of the latter along the axis of the hole 53, and is therefore

arranged exactly alongside the sealing element 54 correctly fitted in the hole

53. ln this way the end 59 may be used to insert the sealing element 54 in

the refill hole 53 by overlaying of the cover 13 on the bottom part 12, engaging

the sealing element 54 in such a way as to impel it towards the position in which it is correctly fitted in the hole 53, as described later.

Operation of the device is as follows.

First and foremost, the head 11 is inserted in the bottom part 12 and the

handles 17 and 18 are then rotated downwards so as to press the respective cams 22 and 23 against the yielding walls 57 and 58 of the printhead 11

accommodated in the bottom part 12 and, accordingly, to produce an inward

depression thereof and a simultaneous reduction of the inner volume of the tank in the printhead 11.

The nozzles 52 of the head 11 are then sealed by means of the cap 56.

The cover 13 is closed over the bottom part 12 so as to bring the end of the

tube 31 to rest against the sealing element 54. The cartridge 33 is then inserted in the sliding element 31 , pushing it

downwards to produce perforation of the cartridge 33, and penetration of the

tube 32 into the refill hole 53 and simultaneous removal from the latter of the

sealing element 54. Next the tank 53 is filled with ink from the cartridge 33 and, when filling has been completed, the sealing element 54, either a new one or

the one removed earlier, is returned to position, in the hole 53, in order to seal

the tank again.

This is accomplished, after lifting the cover 13 off the bottom part 12, by placing the sealing element 54 adjacent to the hole 53 and closing the cover 13

down again so that the tube 31 pushes, by means of the end 59, the sealing element 54 into the hole 53 thereby sealing the tank.

It is obvious that the operation of sealing the tank described above by means of a new sealing element 54, may also be effected without using the cover 13, in a fully manual way.

At this point, with the tank sealed, the handles 17 and 18 are opened, by

turning them upwards, to disengage the cams 22 and 23 from the walls 57 and 58 of the head 11. Accordingly, as the walls 57 and 58 return to their prior conformation, the tank expands correspondingly, reintegrating the reduction in

volume that it initially suffered due to deformation of the walls 57 and 58, and

consequently producing a lowering of the pressure inside the tank itself. At this point the head 10 is ready for use.

It is evident that various changes and/or improvements may be made to

the holder for refilling the ink jet printhead corresponding to the preferred

embodiment described in the foregoing without departing from the scope of the present utility model.

For example, instead of two handles and two corresponding cams, one

handle and a single cam could be provided. In this way, in place of handles

fulcrum-mounted on the bottom part of the holder, elements may be provided suitable for sliding with respect to the bottom part and moving away from a position wherein they do not engage the yielding walls of the head to a position

wherein they do engage them and cause them to yield.

Claims

1 - A holder (10) for refilling of an ink jet printhead (11 ), said printhead (11 )

having resiliently yielding walls (57,58) and containing a tank of said ink

associated with said walls, said tank having a volume variable in relation to the yielding of said walls (57,58), said holder (10) including a bottom part (12) suitable for accommodating said printhead (11 ), characterized by the fact that

said holder (10) comprises mechanical deforming means (17,18,22,23),

supported by said bottom part (12), for resiliently deforming said yielding walls (57,58) of said printhead (11 ), and suitable for selectively assuming a working position wherein they engage with said walls (57,58) to reduce said variable

volume, and an idle position wherein they are disengaged from said walls

(57,58).

2 - A holder (10) according to claim 1 , characterized by the fact that it further comprises a cover (13) selectively overlayable on said bottom part (12), and

positioning means (31 ) supported by said cover (13) and suitable for positioning a refill cartridge (33) containing a refill ink with respect to said

printhead (11 ) accommodated in said bottom part (12), so as to facilitate

hydraulic connection between said refill cartridge (33) and said printhead (11)

for transferring said refill ink from said cartridge (33) to said printhead (11 ).

3 - A holder (10) according to claim 2, wherein said printhead (11 ) is provided with a hole (53) for refilling of said tank, said hole (53) being closed by means

of a removable sealing element (54), characterized by the fact that said

positioning means (31 ) comprise a sliding element (31 ) with respect to said cover (13) and a tube (32) attached to said sliding element (31 ), wherein said sliding element (31) is suitable for positioning said cartridge (33), and wherein said tube (32) has a first end (59) suitable for penetrating said hole (53) of said printhead to remove said sealing element (54) therefrom, and a second end (60) suitable for coupling with said refill cartridge (33), said tube (32) also being

suitable for hydraulically connecting said refill cartridge (33) with said tank of said printhead (11 ) to permit a flow of ink from said refill cartridge (33) to said tank.

4 - A holder (10) according to claim 3, wherein said sliding element (31 )

possesses a work stroke with respect to said cover (13), and is suitable for assuming, in correspondence with one extremity of said stroke, an end-of- stroke position in which said sliding element (31 ) becomes integral with said

cover (13), characterized by the fact that, when said sliding element (31 ) is in

said end-of-stroke position and said cover (13) is overlaid on said bottom part (12), the first end (59) of said tube (32) is arranged at a predetermined distance above and with respect to said hole (53), said predetermined distance

corresponding to a dimension of said sealing element (54), whereby said first end (59) is suitable for inserting in said refill hole (53) said sealing element

(54), when positioned adjacently to the latter, as a result of the overlaying of

said cover (13) on said bottom part (12).

5 - A holder (10) according to claim 1 , characterized by the fact that said

mechanical deforming means (17,18,22,23) are fulcrum-mounted on said bottom part (12) and comprise a handle (17,18) and a cam integral (22,23) with

said handle and suitable for engaging with said yielding walls (57,58).

6 - A holder according to claim 5, characterized by the fact that said cam (22,23) has a substantially cylindrical surface, arranged eccentrically with respect to the pivoting axis of said mechanical deforming means.

7 - A method for refilling an ink jet printhead (11 ) by means of a holder (10), said printhead (11 ) having resiliently yielding walls (57,58) and

containing a tank of said ink associated with said walls, said tank having a

volume variable in relation to the yielding of said walls (57,58), said printhead

also having a hole (53) for refilling of said tank and said hole (53) being closed by means of a removable sealing element (54), and said holder (10) comprising a bottom part (12) suitable for

accommodating said pπnthead (11 ), and mechanical deforming means (17,18,22,23), supported by said bottom part (12), for resiliently deforming said yielding walls (57,58) of said printhead (11 ), and suitable for selectively

assuming a working position wherein they engage with said walls (57,58) to

reduce said variable volume, and an idle position wherein they are disengaged from said walls (57,58). said method comprising the following steps:

accommodation of said printhead (11 ) in said bottom part (12),

actuation of said deforming means (17,18,22,23) to move them away from said idle position to said working position, sealing of the nozzles of the printhead (11 ),

removal of said sealing element (54) from said hole (53) of the printhead

accommodated in the bottom part (12), positioning of said refill cartridge (33) with respect to said printhead (11 )

accommodated in the bottom part (12) and feeding of said tank with ink, through said refill hole (543) by means of said refill cartridge (33), insertion of said sealing element (54) inside said hole (53) for sealing said tank, and

actuation of said deforming means (17,18,22,23) to move them from said

working position to said idle position to produce expansion of said tank and a corresponding depression in the latter.

8 - A method according to claim 7, wherein said holder (10) comprises a cover

(13) overlayable on said bottom part (12) and positioning means (31 ) supported by said cover (13) and suitable for positioning said refill cartridge (33) with respect to the printhead (11 ) accommodated in said bottom part (12),

wherein the step of positioning said cartridge (33) comprises the

following sub-steps: overlaying of said cover (13) on said bottom part (12), and coupling of said refill cartridge (33) with said positioning means (31 ) to

position it with respect to the printhead (11 ) accommodated in the bottom part

(12).

9 - A method according to claim 8, wherein said cover is provided with inserting means (32) suitable for inserting said sealing element (54) in said hole (53) by

the overlaying of said cover (13) on said bottom part (12), and wherein the step

of inserting said sealing element (54) comprises the following sub-steps:

raising of the cover (13), positioning of said sealing element (54) adjacent to said hole (53), and

overlaying of said cover (13) on said bottom part (12) again.