WO2011148161A1

WO2011148161A1 - Valve between a fluids - bearing container and a continuous inkjet printer

Info

Publication number: WO2011148161A1
Application number: PCT/GB2011/050959
Authority: WO
Inventors: James Edward Holmes; Steven Mark Hatch; James Robert Stirling Howarth; Andrew Richard Buchanan Halket; Anthony Raymond Charpentier
Original assignee: Domino Printing Sciences Plc
Priority date: 2010-05-22
Filing date: 2011-05-20
Publication date: 2011-12-01
Also published as: GB201222632D0; GB201008553D0; GB2494087A

Abstract

A non-drip valve is described, particularly useful for incorporation into a continuous inkjet (CIJ) printer. The valve includes an entry section and a receiving section together with a sealing section (15) which can simultaneously form a seal on both.

Description

VALVE BETWEEN A FLUIDS - BEARING CONTAINER AND A CONTINUOUS INKJET PRINTER

Field of the Invention

This invention relates to a continuous inkjet (CIJ) printer and, in particular, to a connection or valve between a fluids-bearing container, and the operating mechanism, of a CIJ printer.

Background to the Invention

Continuous inkjet printers have an ink delivery system to deliver fluids (ink and make-up fluid) to the print head(s) in a controlled manner. In some examples of CIJ printer, fluids are drawn from separate containers and, from time to time, these containers have to be replaced. This can be a messy operation as, inevitably, the removal of the used or near-used container leads to some spillage of the fluid contained therein, or from within the ink delivery system connection. This spillage is messy and wasteful and, given that some of the fluids can be corrosive, parts of the printer coming into contact with such fluids can be damaged if the spilt fluids are not cleaned up.

It is an object of this invention to provide a connection which goes at least some way to addressing the problems described above; or which will at least provide a novel and useful alternative.

Summary of the Invention

Accordingly, in one aspect, the invention provides: a valve comprising a receiving part and an entry part engageable within said receiving part such that, when said receiving and entry parts are engaged, fluid may pass through said valve, said receiving part including a body, a closure slidable within said body between open and closed positions, and a seal section sealing between said closure and said body; said entry part being receivable within said body and engageable with said seal section, the construction and arrangement being such that insertion of said entry part into said body displaces said closure from said closed to said open position, said valve being characterized in that: when said entry part is placed in contact with said closure, there is

substantially no free space between said entry part and said closure, and said seal section is configured to engage both said closure and said entry part before said closure reaches said open position.

Preferably said valve further includes biasing means operable to bias said closure towards said closed position.

Preferably said seal section includes two sealing edges, said edges being spaced in the direction of movement of said closure between said closed and open positions.

Preferably said seal section is defined by a pair of O-rings. Preferably said pair of O-rings are mounted so that a space is provided therebetween. Preferably said space is less than the thickness of one of said O-rings.

Alternatively said seal section is defined by a lip seal including a main sealing edge, a subsidiary wiping edge and a cavity there-between, said lip seal being positioned such that, upon insertion of said entry part into said receiving part, said entry part first contacts said wiping edge.

In a second aspect the invention provides a continuous inkjet printer in which a connection between operative parts of said printer, and a fluids container, includes the valve as set forth above.

Preferably said receiving part and said entry part are arranged about a common, substantially vertical, engagement axis.

Preferably said receiving part is attached to said operative parts whilst said entry part is attached to said fluids container.

Many variations in the way the present invention can be performed will present themselves to those skilled in the art. The description which follows is intended as an illustration only of one means of performing the invention and the lack of description of variants or equivalents should not be regarded as limiting. Wherever possible, a description of a specific element should be deemed to include any and all equivalents thereof whether in existence now or in the future.

Brief Description of the Drawings

The various aspects of the invention will now be described with reference to the accompanying drawings in which: Figure 1 : shows a cross-sectional view through a valve according to the invention, with the valve parts dis-engaged;

Figure 2: shows a similar view to Figure 1 , but with the valve parts

engaged; Figure 3 : shows an enlarged view of one form of seal section

incorporated in the valve shown in Figures 1 & 2; and

Figure 4: shows an enlarged view of an alternative form of seal section for use in the valve shown in Figures 1 & 2.

Detailed Description of Working Embodiment The present invention provides a valve 5 which has been devised, in particular, for incorporation into the ink delivery system of a continuous inkjet (CIJ) printer. To this end, a first or receiving part 6 is incorporated in the ink delivery system 7, forming part of the main electro-mechanical operative parts of the printer. A second, or entry part 8 is attached to a fluids-containing container 9 which, in use, is displaced upwardly into engagement with the ink delivery system 7. A suitable latching mechanism, which is not shown and which does not form part of the invention, is provided to maintain the container 9 in its installed position within the ink delivery system 7.

The valve 5 is such that, when the container 9 is removed from the ink delivery system 7, no fluids will pass, under gravity, from the system 7 though the receiving part 6. Further, the valve has been designed so that, in the course of attaching or detaching the container 9 from the ink delivery system 7, fluid from the ink delivery system will not escape to the surrounding environment. In the form shown, the receiving part 6 comprises a substantially cylindrical body 10 having a seating flange 11 extending around the outside thereof, and a threaded outer surface part 12 to allow screw engagement with the ink delivery system 7. Located within the body 10 is a closure or sliding plug 13, which plug is slidable between a closed position shown in Figure 1 , and an open position as shown in Figure 2. A compressed coil spring 14 biases the plug 13 towards the closed position and it will also be seen that a seal section 15 is located in the lower part of the body 10 so that, when the plug 13 is the closed position, it is sealingly located by the seal section 15 to prevent fluid in the ink delivery system from passing out through the valve part 6.

As shown, the plug 13 is T-shaped in cross-section, the spring 14 acting against the wider flat top plate 16. Ports or cut-outs 17 are provided in the plate 16 so that, when the valve parts 6 and 8 are engaged as shown in Figure 2, fluid from the service module may flow past the plug 13 and into the ink delivery system 7 as shown by the arrows in Figure 2.

The second or entry part 8 of the valve is, in the form shown, a simple tubular spigot 18 whose outer diameter is substantially the same as the outer diameter of the plug 13. Thus, as the spigot 18 is engaged into the valve part 6, the seal section 15 acts against the surface of the spigot 18.

It will be appreciated that the act of displacing the container 9 up into contact with the ink delivery system 7 displaces the plug 13 from the closed position shown in Figure 1 , to the open position shown in Figure 2. It is not until the spigot 18 has passed entirely through the seal section 15, and the plug 13 is fully retracted, that ports 19 in the spigot are exposed to allow the exchange of fluids between the container 9 and the ink delivery system 7. It will be seen that the upper end of the spigot is formed into a socket 20 whilst the lower end of the plug is formed with a corresponding projection 21. The co-operating parts 20 & 21 not only locate the valve parts 6 & 8 for correct engagement and alignment, but also ensure that there is no free space between the parts. The latter feature ensures that either the spool 13 or the spigot 18 is in engagement with the seal section 15 at all times, thus preventing fluid from leaking from the ink delivery system 7.

As illustrated in Figures 1 & 2 a displaceable closure 30 may be provided about the spigot 18 to prevent leakage from the container 9 before the same is fully engaged with the ink delivery system 7. In the form shown the closure 30 has a further seal section 31 which, when the container 9 is separate from the printer, overlies ports 19 in the spigot 18. A locking ring 32 retains one or more sealing members within the closure 30 and a compression spring 33 biases the closure into the position, limited by the locking ring 32, in which the seal section 31 overlies the ports 19.

As the container is displaced up into the printer, the closure 30 of the container is engaged and displaced by the fixed cylindrical body 10 of the receiving part 6. Further displacement of the container thus causes the closure 30 to be displaced down the spigot 18, against the bias of spring 33.

Turning now to Figures 3 & 4, an important feature of the seal section is that it simultaneously provides a wiping action against both valve parts whilst not allowing fluid to accumulate between the parts. As can be seen, both forms of seal section 15 include two axially spaced sealing edges, each of which can operate independently of the other. This means that a seal can be formed with the spigot 18, even when the spigot is not exactly aligned with the spool 13, before the seal between the spool and the seal section 15 has been broken. Further, because the outer surfaces of both spool and spigot are continuously wiped as the container is attached or removed, and because there is substantially no gap between the spigot and the spool, there is no opportunity for a bubble of fluid to accumulate and drip from the ink-delivery system 7.

In the form shown in Figure 3 the seal section is provided by a single component 22 having a main or upper sealing edge 23 and a lower or auxiliary wiping edge 24, the edges 23 and 24 being separated by a cavity 25. It will be appreciate that the cavity 25 allows one of the edges 23 or 24 to be displaced without causing displacement of the other.

In the form shown in Figure 4, the seal section is provided by two O-ring seals 26, preferably having a space 27 there-between. The space 27 ensures that the seals 26 do not bind together and allows each to function independently of the other.

It will thus be appreciated that the present invention provides a simple yet effective connection or valve arrangement, particularly useful for effecting a seal between operative components of a CIJ printer.

Claims

1. A valve comprising a receiving part and an entry part engageable within said receiving part such that, when said receiving and entry parts are engaged, fluid may pass through said valve, said receiving part including a body, a closure slidable within said body between open and closed positions, and a seal section sealing between said closure and said body; said entry part being receivable within said body and engageable with said seal section, the construction and arrangement being such that insertion of said entry part into said body displaces said closure from said closed to said open position, said valve being characterized in that: when said entry part is placed in contact with said closure, there is substantially no free space between said entry part and said closure, and said seal section is configured to engage both said closure and said entry part before said closure reaches said open position.

2. A valve as claimed in claim 1 further including biasing means operable to bias said closure towards said closed position.

3. A valve as claimed in claim 1 or claim 2 wherein said seal section includes two sealing edges, said edges being spaced in the direction of movement of said closure between said closed and open positions.

A valve as claimed in any one of claims 1 to 3 wherein said seal section is defined by a pair of O-rings.

A valve as claimed in claim 4 wherein said pair of O-rings are mounted so that a space remains there-between.

A valve as claimed in claim 5 wherein said space is less than the thickness of one of said o-rings.

A valve as claimed in any one of claims 1 to 3 wherein said seal section is defined by a lip seal including a main sealing edge, a subsidiary wiping edge and a cavity there-between, said lip seal being positioned such that, upon insertion of said entry part into said receiving part, said entry part first contacts said wiping edge.

A continuous inkjet printer in which a connection between operative parts of said printer, and a fluids container, includes the valve as claimed in any one of claims 1 to 7.

9. A printer as claimed in claim 8 wherein said receiving part and said entry part are arranged about a common, substantially vertical, engagement axis.

10. A printer as claimed in claim 8 or claim 9 wherein said receiving part is attached to said operative parts whilst said entry part is attached to said fluids container.