WO2023057093A1

WO2023057093A1 - Cleaning assembly

Info

Publication number: WO2023057093A1
Application number: PCT/EP2022/050292
Authority: WO
Inventors: Fabrizio TOMASIN
Original assignee: New System S.R.L.
Priority date: 2021-10-07
Filing date: 2022-01-07
Publication date: 2023-04-13
Also published as: IT202100025556A1

Abstract

A cleaning assembly (100) for a printer (200), the cleaning assembly comprising a tank (103) for collecting waste fluid, the tank comprising at least one aperture (107) having an angled side wall (106) for receiving waste fluid into the interior of the tank from a print head (140) of the printer; wherein the angled side wall of the aperture is configured to direct the waste fluid into the interior of the tank; and wherein the tank further comprises at least one nozzle (109) which is configured to apply a vacuum force to the print head of the printer such as to clean the print head.

Description

CLEANING ASSEMBLY

FIELD OF THE INVENTION

This invention relates to a cleaning assembly for a printer, in particular an inkjet printer.

BACKGROUND TO THE INVENTION

Printers, particularly inkjet printers, operate by ejecting ink in a predetermined pattern upon a substrate from a print head assembly typically comprising a plurality of nozzles from which the ink is ejected. Over time, residue resulting from the expulsion of ink from these nozzles will dry and remain on the nozzles, resulting in dust and other particulates adhering to the nozzles which consequently disrupts the ejection path of the ink from the nozzle such that the ink droplets are ejected in an uncontrolled manner, or it disrupts the ejection path entirely such that no ink can be ejected from the nozzle at all. These problems consequently lead to significantly impaired image quality during printing.

It is known to provide a cleaning assembly for a printer for cleaning the print head assembly, in particular, the nozzles thereof. A prior art embodiment of such a cleaning assembly 1 is shown in Figure 1A. The cleaning assembly 1 is typically provided on a suitable support for mounting the cleaning assembly 1 within the printer. This cleaning assembly 1 comprises a tank 3 for receiving waste fluid, in particular, ink from the print head assembly. The interior of the tank 3 defines a waste fluid collector. The upper surface 5 of the tank 3 comprises a plurality of apertures 7 through which the waste fluid may be ejected from the printer head into the tank 3. The plurality of apertures 7 are spaced apart from one another across the upper surface of the tank 3, the apertures 7 being provided in a sequential fashion one after the other. The cleaning assembly 1 further comprises a plurality of vacuum nozzles 9 which are positioned upon the intervening portions 6 of the upper surface, the intervening portions 6 separating the respective apertures 7 from one another.

In-use, the print head assembly, typically comprising four print heads to correspond to the four apertures 7 shown in Figure 1A, is first configured to adopt a position substantially above the apertures 7. Once there, the printer heads are configured to purge the remaining fluid contained within each head by ejecting the remaining fluid through their nozzles. This waste ink will pass through the apertures 7 and into the interior of the tank 3. To this end, the tank 3 comprises an outlet 9 to provide a path by which the waste fluid may be drained from the tank 3. Once the printer heads have purged their remaining ink, they may adopt a position directly above the vacuum nozzles 9, following which, a vacuum source is configured to apply a suction force to remove any remaining ink on the nozzles 9 of the printer head. The cleaning assembly 1 comprises one or more vacuum inlets 11 located on the tank 3 to which a suitable vacuum source may be fluidly coupled.

There are a number of deficiencies with this prior art embodiment shown in Figure 1A. Firstly, the sequential arrangement of the apertures 7 upon the upper surface of the cleaning assembly results in the dimensions of the cleaning assembly being quite large, which takes up a significant portion of the limited space available within the printer within which the cleaning assembly is installed. Secondly, the upper surface of the tank 3 is substantially planar, which results in some of the waste ink not draining through the apertures 7, and instead accumulating and/or evaporating upon the upper surface of the tank 3. For example, the ink may dry as a residue and clog one or more of the vacuum nozzles 9, leading to impaired cleaning efficacy of the cleaning assembly 1 over time.

Accordingly, it is a desire of the present invention to overcome the deficiencies set out above.

SUMMARY OF THE INVENTION

Accordingly, a first aspect of the present invention provides a cleaning assembly comprising: a tank for collecting waste fluid, the tank comprising at least one aperture having an angled side wall for receiving waste fluid into the interior of the tank from a print head of the printer; wherein the angled side wall of the aperture is configured to direct the waste fluid into the interior of the tank; and wherein the tank further comprises at least one nozzle which is configured to apply a vacuum force to the print head of the printer such as to clean the print head.

The nozzle can be located within the aperture.

The tank can comprise a plurality of nozzles which are located within the aperture.

The tank can further comprise an inlet which is in fluid communication with the nozzle for coupling of a vacuum source. The tank further can comprise an outlet for draining the waste fluid from the interior of the tank.

The outlet can be located lower on the tank than the inlet.

The angled side wall can comprise a baffle which is located within the aperture and is angled to direct fluid received into the aperture into the interior of the tank.

The baffle can comprise an elongate member which extends along the length of the aperture.

The baffle can extend along the centre of the aperture such that it divides the aperture into first and second sections.

The first section of the aperture can be unobstructed and the vacuum nozzles can be located within the second section of the aperture.

The plurality of vacuum nozzles can be arranged in a linear fashion one after the other within the second section of aperture such that the vacuum nozzles extend substantially along the length of the aperture.

The tank can comprise a plurality of apertures which are spaced apart across a top wall of the tank in a staggered formation.

The cleaning assembly can further comprise a wiper unit which is configured to wipe the print head of the printer.

The wiper unit can comprise a wiper blade which is movable between a retracted state and an extended state, wherein in the retracted state, the wiper blade lies substantially flush with the top wall of the tank, and in the extended state, the wiper blade extends above and away from the surface of the top wall for contacting the print head in-use.

A second aspect of the present invention provides a printer comprising: a substrate support device configured to support a substrate thereon; a print head assembly comprising at least one print head having a plurality of print head nozzles for ejecting ink droplets in a controlled manner upon the substrate in a predetermined pattern; and a cleaning assembly comprising: a tank for collecting waste fluid, the tank comprising at least one aperture having an angled side wall for receiving waste fluid into the interior of the tank from a print head of the printer; wherein the angled side wall of the aperture is configured to direct the waste fluid into the interior of the tank; and wherein the tank further comprises at least one nozzle which is configured to apply a vacuum force to the print head of the printer, such as to clean the print head.

The printer can further comprise a controller which is communicatively coupled to the substrate support device, print head assembly and/or cleaning assembly.

When the controller determines that the print head assembly requires cleaning, the print head assembly can be configured to adopt a first position relative to the cleaning assembly, for purging waste fluid from the print head.

When in the first position, the print head can be configured to adopt a position substantially above the aperture, wherein the print head is located offset to the centre of the aperture, such that the print head nozzles are positioned substantially above the first side of the aperture, for ejecting waste fluid from the print head onto the baffle.

When the controller determines that all of the waste fluid has been ejected from the print head, the print head assembly can be configured to adopt a second position relative to the cleaning assembly for cleaning the print head.

When in the second position, the print head can be configured to adopt a position substantially above the aperture, wherein the print head is located offset to the centre of the aperture such that the print head nozzles are positioned substantially above the second side of the aperture above the vacuum nozzle for cleaning by the vacuum nozzle.

When the controller determines that the printer head has been cleaned by the vacuum nozzle, the wiper blade of the wiper unit can be configured to adopt the extended state, wherein the printer head assembly is configured to displace the print head relative to the wiper blade, such that the wiper blade contacts the print head nozzles so the wiper blade removes any waste fluid and/or debris present on the print head nozzle. A third aspect of the present invention provides a method of cleaning a print head assembly, comprising at least one print head having a plurality of print head nozzles for ejecting ink droplets, using the cleaning assembly as recited in any previous statement of invention, the method comprising: purging waste fluid from within the print head into the tank through the aperture having the angled side wall; and vacuuming the print head using the at least one vacuum nozzle to clean the nozzles of the print head.

The method can further comprise, subsequent to vacuuming the print head, wiping the print head with a wiper blade such as to remove any waste fluid and/or debris present on the print head nozzle.

Purging the waste fluid from within the print head into the tank through the aperture, having the angled side wall, can further comprise the print head adopting a first position substantially above the aperture and ejecting waste fluid from the print head onto the angled side wall.

Vacuuming the print head using the at least one vacuum nozzle to clean the nozzles of the print head can further comprise the print head adopting a second position substantially above the aperture, applying the vacuum force from the vacuum nozzle to clean the print head nozzles.

BRIEF DESCRIPTION OF THE DRAWINGS

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

Figure 1A is a front perspective view of a prior art embodiment of a cleaning assembly for cleaning print heads of an inkjet printer;

Figure 1 is a side perspective view of a cleaning assembly embodying a first aspect of the present invention;

Figure 2 is a further side perspective view of the cleaning assembly;

Figure 3 is a rear perspective view of the cleaning assembly;

Figure 4 is a front perspective view of the cleaning assembly;

Figure 5 is a further front perspective view of the cleaning assembly showing the positioning of a plurality of print heads of a printer relative to the cleaning assembly; Figure 6 is a front perspective view of one of the print heads;

Figure 7 is a front plan view of the print head;

Figure 8 is a bottom plan view of the print head;

Figure 9 is a further bottom plan view of the print head of Figure 8, in particular showing the print head nozzles;

Figure 10 is a semi-sectional front view of the cleaning assembly showing the positioning of the plurality of print heads of the printer relative to the cleaning assembly, in particular showing the cleaning assembly during a purging process;

Figure 11 is a further semi-sectional front view of the cleaning assembly showing the positioning of the plurality of print heads of the printer relative to the cleaning assembly, in particular showing the cleaning assembly during a vacuuming process; Figure 12 is a sectional side view of the cleaning assembly during the vacuuming process;

Figure 13 is a further sectional side view of the cleaning assembly during the vacuuming process;

Figure 14 is a further sectional side view of the cleaning assembly during the vacuuming process;

Figure 15 is a front perspective view of a printer comprising the cleaning assembly which embodies a second aspect of the present invention; and

Figure 16 is an interior view of the printer, showing the location of the cleaning assembly therein.

DETAILED DESCRIPTION

Referring now to the drawings, in particular Figures 1 to 5, there is shown, generally indicated by the reference numeral 100, a cleaning assembly embodying a first aspect of the present invention. The cleaning assembly 100 is typically coupled, such as being mounted by a suitable mounting assembly 102, within a printer 200 which typically comprises an inkjet printer such as that shown in Figures 15 and 16. The printer 200 typically comprises at least a print head assembly 210 and a substrate support device 220. The print head assembly 210 typically includes at least one print head 140 having a plurality of nozzles 141 for ejecting ink droplets in a controlled manner upon a substrate positioned on the substrate support device 220. To this end, the print head assembly 140 further includes a suitable ink supply provided with a container 142 which is for supplying fluid thereto. The substrate support device 220 is configured to support a substrate during the printing process. To this end, the substrate support device 220 typically comprises a stage or chuck or any other suitable device suitable for retaining the substrate thereon. The substrate can comprise a Printed Circuit Board (PCB) substrate formed with a copper layer covering an upper surface thereof. The inkjet printer 200 being configured to print a predetermined pattern upon the PCB substrate in use for the production of PCBs as mentioned in further detail below.

The printer 200, typically comprising an inkjet printer, is configured to selectively print photosensitive patterns on the PCB substrate using an ink typically comprising an etchresistant ink which is solvent based. Once the patterns have been printed on the PCB substrate, the substrate can then be dried to cure the pattern upon the substrate. Subsequently the PCB substrate may then be etched, typically by wet etching, to remove the parts of the conductive layer to which the patterns have not been printed, such that only the patterned sections remain on the substrate. Finally, the etch-resistant ink is typically stripped from the surface of the patterns to expose the conductive traces remaining underneath on the substrate. The steps of etching and/or stripping of the printed PCB substrate may be performed using another apparatus separate to the printer 200.

The etch-resistant ink can comprise a solvent-based ink, in an embodiment the etchresistant ink may comprise: a photoresist constituting 33 - 64 wt. % of said photosensitive ink; a solvent constituting 19.99 - 59.99 wt. % of said photosensitive ink; a humectant constituting 1 - 10 wt. % of said photosensitive ink; a surfactant constituting 0.01 - 0.1 wt. % of said photosensitive ink; an adhesion promoter constituting 1 - 3 wt. % of said photosensitive ink, said adhesion promoter having a molecular weight between 1700 - 70000 Da; and a basic solution constituting 2 - 3 wt. % of said photosensitive ink, said adhesion promoter being dissolved in said basic solution.

The cleaning assembly 100 typically comprises a tank 103, the interior of which defines a waste fluid collector. To this end, the tank 103 is typically substantially cuboidal in shape having four side walls 114, 115, 116, 117 which extend between the top wall 105 and the bottom wall 104. The bottom wall 104 of the cleaning assembly 100 being that which is closest to the ground surface upon which the printer 200, within which the cleaning assembly 101 is typically located, rests in-use. The cleaning assembly 100 comprises at least one aperture 107 for receiving waste fluid into the interior of the tank from the print head 140 of the printer 200. To this end, the top wall 105 of the tank 103 comprises the at least one aperture 107, such as a plurality of apertures 107, through which the waste fluid may be ejected from the printer heads 140 into interior of the tank 103 in-use. The aperture 107 has at least one angled side wall 106 for directing the waste fluid into the interior of the tank 103. For example, the aperture 107 may be angled around its periphery. In an embodiment such as that shown in Figures 1 to 5, the cleaning assembly 100 comprises four apertures 107 provided in its top wall 105. To this end, the apertures 107 are spaced across the top wall 105 of the tank 103 in a staggered formation. Each of the apertures 107 typically comprise elongate apertures which can extend more than 50% across the width of the top wall 105. Advantageously, the staggered formation of the apertures 107 means that the apertures 107 can be located adjacent to one another in a more compact manner than in prior art embodiments such as that shown in Figure 1 A. The top side 105 of the tank 3 is typically removable from the cleaning assembly 100. Advantageously, this allows for access into the cleaning assembly 100 for repair and maintenance in-use.

The cleaning assembly 100, in particular the tank 103, typically comprises one or more outlets 110 through which waste fluid contained within the interior of the tank 103 may be removed from the cleaning assembly. To this end, one of the side walls 114 of the cleaning assembly 100 typically comprises a stepped side wall, with the plurality of outlets being located on the lower of the stepped side wall portions towards the in-use bottom of the cleaning assembly 100.

The cleaning assembly 100 can comprise a baffle 108 which is configured to direct fluid received into the aperture 107 into the interior of the tank 103. To this end, each of the apertures 107 can comprise a baffle 108 which is located within the aperture 107, which is configured to direct fluid received into the aperture 107 into the interior of the tank 103. The baffle 108 typically comprises an elongate member which typically extends at least in part along the length of the aperture 107. In an instance, the baffle 108 extends the entire length of the aperture 108. The baffle 108 can be provided and can extend along the centre of the aperture 107. The baffle 108 typically comprises one or more angled surfaces which are angled towards the interior of the tank 103 such that any fluid received upon the baffle 108 will drain downwards under gravity into the interior of the tank 103. The angled surfaces are angled relative to a vertical axis which extends perpendicular to the ground surface upon which the printer 200, within which the cleaning assembly 100 is installed, rests in-use. Typically, the angle of the one or more angled surfaces is greater than 20°. In an embodiment, the angle of the one or more angled surfaces is equal to about 45°. The angled side wall of the aperture 107 may comprise the baffle 108. however, this may be in addition to or alternative to one or more other angled side walls 106 of the aperture 107.

The cleaning assembly 100 further comprises one or more vacuum nozzles 109 to which a vacuum source (not shown) may be fluidly coupled for cleaning the print heads 140, in particular the nozzles 141 of the print head 140. To this end, the cleaning assembly 100 further comprises one or more inlets 111 which are in fluid communication with the vacuum nozzles 109 for coupling a suitable vacuum source such as a pump or the like. The inlets 111 can be located above the one or more waste fluid outlets 110, typically upon the same side wall 114. In an embodiment, as mentioned previously, at least one side wall 114 of the cleaning assembly 100 comprises a stepped side wall 114; the inlets 111 can be located on the upper stepped side wall portion whilst the outlets 110 are located on the lower stepped side wall portion. The waste fluid outlets 110 are located lower than the inlets 111 such that the vacuum force, when applied at the inlet, does not suck out all of the waste fluid located within the interior of the tank 103.

The vacuum nozzles 109 are typically located upon the top wall 105 of the tank 103, such as within each of the apertures 107. In an embodiment, as shown in Figures 1 to 5, each aperture 107 comprises a plurality of vacuum nozzles 109 which are arranged in a linear fashion one after the other within the aperture 107, such that the vacuum nozzles 109 extend along the length of the aperture 107. The vacuum nozzles 109 are arranged such that the nozzle opening, through which the vacuum force is applied, is directed upwards i.e. away from the interior of the tank 103, such that when the print head 140 adopts a position substantially above the vacuum nozzles 109 (such as that shown in Figure 5) the vacuum force applied by the vacuum nozzles 109 is configured to clean the print head nozzles 141 by sucking away any remaining ink, residue and/or debris. To this end, the vacuum nozzle 109 is typically shaped and dimensioned such that the walls of the vacuum nozzle 109 direct any waste fluid received thereon towards the interior of the tank 103. To this end, the vacuum nozzle 109 can comprise one or more angled side walls for directing waste fluid received thereon towards the interior of the tank 103. For example, the nozzle body is narrowest at the nozzle outlet with the walls of the nozzle body extending from the nozzle outlet towards the interior of the tank 103, typically at an oblique angle, such that any fluid which comes into contact with the vacuum nozzle 109 surface will drain downwards into the tank 103. Advantageously, the angled surfaces of the vacuum nozzles 109 further prevent any fluid accumulating within the cleaning assembly 100, as any fluid received thereon will drain towards the interior of the tank 103 for removal.

The baffle 108 can divide each aperture 107 into two sections, typically comprising two sides 122, 123 of the aperture 107, with the aperture 107 being substantially open and unobstructed on a first side 122 of the baffle 108 and the vacuum nozzles 109 being located on the second side 123 of the baffle 108 within the aperture 107. The vacuum nozzles 109 may be arranged within the aperture 107 such that there are no openings into the interior of the tank 103 provided between the respective nozzles 109. However, gaps can be provided between and/or surrounding the respective vacuum nozzles 109 such that any fluid, such as that ejected from the print heads 140, may drain into the tank 103 in the event of any spillage into the second side of the aperture 107 and/or run off from the cleaning of the print head 140 using the vacuum nozzles 109.

The cleaning assembly 100 may further comprise one or more secondary apertures 119, typically provided in the top wall 105, which provide a further entry path into the interior of the tank 103. The secondary apertures 119 may be located adjacent to one or more of the apertures 107, typically along the same longitudinal axis.

The cleaning assembly 100 further comprises a wiper unit 120. The wiper unit 120 is configured to wipe the print head 140, typically subsequent to cleaning using the vacuum nozzles 109, in particular the print head nozzles 141. Advantageously, the wiper unit 120 removes any remaining ink, residue and/or debris remaining after the purging and vacuuming steps. The wiper unit typically comprises a wiper blade 121 which the print head 140 is configured to displace relative thereto to clean the print head nozzles 141. In an alternative embodiment, the wiper blade 141 may be configured to displace relative to the print head 140. The wiper blade 141 is typically made from nylon and/or polyester, however, it may alternatively be made from any other suitable material. The cleaning assembly 100 can comprise a plurality of wiper units 120; in particular, the cleaning assembly can comprise a wiper unit 120 for each aperture 107.

For example, in the embodiment shown in Figures 1 to 5, the cleaning assembly 100 comprises four apertures 107 and consequently the cleaning assembly 100 also comprises four wiper units 120. The wiper unit 120 can be located upon the top wall 105. Typically the wiper unit 120 is located at an end of the aperture 107, the wiper unit 120 being provided such that it extends substantially perpendicular relative to the elongate apertures 107. The wiper unit 120 is movable between a retracted state and an extended state. In the retracted state, the wiper blade 121 lies substantially flush with the surface of the top wall 105. In the extended state the wiper blade 121 extends above and away from the surface of the top wall 105 such that the wiper blade 121 is operable to contact the print head 140 as it displaces relative thereto, the wiper blade 121 contacting the nozzles of the print head 141 as it displaces over the wiper blade 121 , such that the wiper blade 121 removes any ink, residue and/or debris on the print head nozzles 141 . Figures 6 to 9 illustrate an embodiment of the print head 140. The print head 140 typically comprises a container 142 for ink supply, which is typically substantially cuboidal in shape which substantially defines the print head body. The container 142 is configured for coupling to the print head assembly at one end and to a nozzle plate 143 at the opposing end. The nozzle plate 143 being removably coupled to the container 142. The nozzle plate 143 comprises the plurality of print head nozzles 141 (e.g., six rows of print head nozzles 141 ) through which ink may be ejected in-use.

In-use, the cleaning assembly 100 is typically mounted within a printer 200 such as that shown in Figures 15 and 16. The cleaning assembly 100 is typically located adjacent or in close proximity to the print head assembly 210. Subsequent to the printer 200 completing printing on the substrate, typically the PCB substrate, the printer heads 140 will require cleaning, as over time ink will dry and accumulate within the nozzles 141 which would lead to impaired print quality. Accordingly, the printer 200 comprises a controller (not shown) which is configured to cause the print head assembly to undergo a cleaning process using the cleaning assembly 100. Typically, the controller will be pre-programmed with the dimensions of the various components within the printer 200 and accordingly be configured to adopt suitable positions in relation thereto during the various printing, cleaning and other operations occurring within the printer 200. Further, the controller will be configured to cause the print head assembly 210 to undergo cleaning after a predetermined number of printing actions have occurred and/or a predetermined period of time has elapsed since the print head assembly 210 last underwent cleaning.

In particular, the cleaning process includes a purging process where the printer heads 140 adopt a first position above the cleaning assembly 100, such as that shown in Figure 10. In the first position or purging position, the printer heads 140 are located substantially above the apertures 107. In particular, the printer heads 140 are typically located offset to the centre of the aperture 107 such that the print head nozzles 141 are positioned substantially above the first side 122 of the aperture 107, the first side 122 being the side of the aperture 107 comprising a substantially unobstructed opening into the interior of the tank 103. In this position, the printer heads 140 are configured to eject any ink remaining within the container 142 from the print head nozzles 141 onto the baffle 108 into the interior of the tank 103. The baffle 108, in particular the angled surfaces thereof, ensures that all of the ink ejected from the print head nozzles 141 drains into the interior of the tank 103 through the aperture 107 and does not accumulate on any planar surface. The nozzles 141 will typically eject the ink over a time period approximately equal to two seconds. However, this purging may take more or less time depending upon the volume of ink to be ejected from the print head container 142. The ink purged from the print heads

140 will drain into the interior of the tank 103, from where it will typically drain into an external tank (not shown) via the outlets 110 or otherwise and be evacuated from the cleaning assembly 100. The distance between the printer head 140, in particular the print head nozzles 141 and the baffle 108, is typically about 4mm when the printer heads 140 adopt the first position.

Once the ink has been ejected from the print head 140, the purging process is complete. The cleaning process further comprises a vacuum process. Subsequent to the purging process, the printer heads 140 are configured to adopt a second position above the cleaning assembly 100, such as that shown in Figures 11 to 14. In the second position or vacuuming position, the printer heads 140 are located substantially above the apertures 107. In particular, the printer heads 140 are typically located offset to the centre of the aperture 107, in the opposing direction to the position which the print heads 140 adopt in the first position, such that the print head nozzles 141 are positioned substantially above the second side 123 of the aperture 107, the second side being the side of the aperture 107 comprising the vacuum nozzles 109. In this second position the vacuum nozzles 109 are configured to apply a vacuum force to the print head 140, in particular, the print head nozzles 141 , to remove any residual ink on the print head nozzles 141 , by applying the suctional vacuum force.

Whilst the vacuum nozzles are applying the vacuum force to the print head nozzles 141 , the print head 140 is configured to move along a linear axis which extends parallel to the aperture 107, in a backward and/or forward direction, such that all of the print head nozzles

141 receive the vacuum force applied by the vacuum nozzles 141 in-use. The distance between the printer head 140, in particular the print head nozzles 141 and the vacuum nozzles 109 is typically about 0.2 mm when the printer heads 140 adopt the second position. The distance between the printer head 140 when in the first position and the printer head 140 when in the second position is about 9mm.

The cleaning process further comprises wiping the print heads 140, in particular the print head nozzles 141. Subsequent to the vacuum process as described above, the cleaning assembly 100, in particular the wiper unit 120, is configured to clean the print head nozzles 141. After the vacuum process ends, the wiper blade 121 is configured to adopt the extended state wherein the print heads 140 are configured to displace relative to wiper blade 121 , such that the wiper blade 121 contacts the print head nozzles 141 as the print heads 140 displace relative to the wiper blade 121 such that the wiper blade 121 removes any remaining ink and/or debris present on the print head nozzle 141 .

Accordingly, a further aspect of the invention provides a method of cleaning a printer 200, in particular, a print head 140 of a printer 200 typically using the cleaning assembly 100 embodying the first aspect of the present invention. The method comprising: purging ink from within the print head 140; and vacuuming the print head 140. The method may further comprise wiping the print head 140.

It will be understood that, while exemplary features of a method of cleaning a print head assembly have been described, such an arrangement is not to be construed as limiting the invention to such features. The method may be implemented in software, firmware, hardware, or a combination thereof. In one mode, the method is implemented in software, as an executable program, and is executed by one or more special or general purpose digital computer(s), such as a personal computer (PC; IBM-compatible, Apple-compatible, or otherwise), personal digital assistant, workstation, minicomputer, or mainframe computer. The steps of the method may be implemented by a server or computer in which the software modules reside or partially reside.

Generally, in terms of hardware architecture, such a computer will include, as will be well understood by the person skilled in the art, a processor, memory, and one or more input and/or output (I/O) devices (or peripherals) that are communicatively coupled via a local interface. The local interface can be, for example, but not limited to, one or more buses or other wired or wireless connections, as is known in the art. The local interface may have additional elements, such as controllers, buffers (caches), drivers, repeaters, and receivers, to enable communications. Further, the local interface may include address, control, and/or data connections to enable appropriate communications among the other computer components.

The processor(s), i.e. of the control system, may be programmed to perform the functions of the method of cleaning a print head assembly. The processor(s) is a hardware device for executing software, particularly software stored in memory. Processor(s) can be any custom made or commercially available processor, a primary processing unit (CPU), an auxiliary processor among several processors associated with a computer, a semiconductor-based microprocessor (in the form of a microchip or chip set), a macroprocessor, or generally any device for executing software instructions. Memory is associated with processor(s) and can include any one or a combination of volatile memory elements (e.g., random access memory (RAM, such as DRAM, SRAM, SDRAM, etc.)) and non-volatile memory elements (e.g., ROM, hard drive, tape, CDROM, etc.). Moreover, memory may incorporate electronic, magnetic, optical, and/or other types of storage media. Memory can have a distributed architecture where various components are situated remote from one another, but are still accessed by processor(s).

The software in memory may include one or more separate programs. The separate programs comprise ordered listings of executable instructions for implementing logical functions in order to implement the functions of the modules. In the example of heretofore described, the software in memory includes the one or more components of the method and is executable on a suitable operating system (O/S).

The present disclosure may include components provided as a source program executable program (object code), script, or any other entity comprising a set of instructions to be performed. When a source program, the program needs to be translated via a compiler, assembler, interpreter, or the like, which may or may not be included within the memory, so as to operate properly in connection with the O/S. Furthermore, a methodology implemented according to the teaching may be expressed as (a) an object-oriented programming language, which has classes of data and methods, or (b) a procedural programming language, which has routines, subroutines, and/or functions, for example but not limited to, C, C++, Pascal, Basic, Fortran, Cobol, Ped, Java, and Ada.

When the method is implemented in software, it should be noted that such software can be stored on any computer-readable medium for use by or in connection with any computer related system or method. In the context of this teaching, a computer-readable medium is an electronic, magnetic, optical, or other physical device or assembly that can contain or store a computer program for use by or in connection with a computer related system or method. Such an arrangement can be embodied in any computer-readable medium for use by or in connection with an instruction execution system, apparatus, or device, such as a computer-based system, processor-containing system, or other system that can fetch the instructions from the instruction execution system, apparatus, or device and execute the instructions. In the context of this disclosure, a "computer-readable medium" can be any assembly that can store, communicate, propagate, or transport the program for use by or in connection with the instruction execution system, apparatus, or device. The computer readable medium can be for example, but not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, device, or propagation medium. Any process descriptions or blocks in the Figures should be understood as representing modules, segments, or portions of code which include one or more executable instructions for implementing specific logical functions or steps in the process, as would be understood by those having ordinary skill in the art.

The above detailed description of embodiments of the disclosure is not intended to be exhaustive nor to limit the disclosure to the exact form disclosed. While specific examples for the disclosure are described above for illustrative purposes, those skilled in the relevant art will recognize various modifications are possible within the scope of the disclosure. For example, while processes and blocks have been demonstrated in a particular order, different implementations may perform routines or employ systems having blocks, in an alternate order, and some processes or blocks may be deleted, supplemented, added, moved, separated, combined, and/or modified to provide different combinations or subcombinations. Each of these processes or blocks may be implemented in a variety of alternate ways. Also, while processes or blocks are at times shown as being performed in sequence, these processes or blocks may instead be performed or implemented in parallel or may be performed at different times. The results of processes or blocks may be also held in a non-persistent store as a method of increasing throughput and reducing processing requirements.

The invention is not limited to the embodiment(s) described herein but can be amended or modified without departing from the scope of the present invention.

Claims

1 . A cleaning assembly for a printer, the cleaning assembly comprising: a tank for collecting waste fluid, the tank comprising at least one aperture having an angled side wall for receiving waste fluid into an interior of the tank from a print head of the printer; wherein the angled side wall of the aperture is configured to direct the waste fluid into the interior of the tank; and wherein the tank further comprises at least one nozzle which is configured to apply a vacuum force to the print head of the printer to clean the print head.

2. The cleaning assembly of claim 1 , wherein the nozzle is located within the aperture.

3. The cleaning assembly of claim 1 , wherein the tank comprises a plurality of the nozzles which are located within the aperture.

4. The cleaning assembly of claim 1 , wherein the tank further comprises an inlet which is in fluid communication with the nozzle for coupling a vacuum source.

5. The cleaning assembly of claim 4, wherein the tank further comprises an outlet for draining the waste fluid from the interior of the tank.

6. The cleaning assembly of claim 5, wherein the outlet is located lower on the tank than the inlet.

7. The cleaning assembly of claim 1 , wherein the angled side wall comprises a baffle which is located within the aperture and is angled to direct fluid received into the aperture into the interior of the tank.

8. The cleaning assembly of claim 7, wherein the baffle comprises an elongate member which extends along a length of the aperture.

9. The cleaning assembly of claim 7, wherein the baffle extends along a centre of the aperture such that it divides the aperture into first and second sections.

10. The cleaning assembly of claim 9, wherein the first section of the aperture is unobstructed and the nozzles are located within the second section of the aperture.

11. The cleaning assembly of claim 10, wherein the tank comprises a plurality of the nozzles, wherein the plurality of the nozzles are arranged in a linear fashion one after the other within the second section of aperture, such that the plurality of the nozzles extend substantially along a length of the aperture.

12. The cleaning assembly of claim 1 , wherein the tank comprises a plurality of the apertures which are spaced apart across a top wall of the tank in a staggered formation.

13. The cleaning assembly of claim 1 , further comprising a wiper unit which is configured to wipe the print head of the printer.

14. The cleaning assembly of claim 13, wherein the wiper unit comprises a wiper blade which is movable between a retracted state and an extended state, wherein in the retracted state the wiper blade lies substantially flush with a top wall of the tank and in the extended state the wiper blade extends above and away from a surface of the top wall for contacting the print head in-use.

15. A printer comprising: a substrate support device configured to support a substrate thereon; a print head assembly comprising at least one print head having a plurality of print head nozzles for ejecting ink droplets in a controlled manner upon the substrate in a predetermined pattern; and the cleaning assembly as recited in claim 1 .

16. The printer of claim 15, further comprising a controller which is communicatively coupled to the substrate support device, print head assembly and/or cleaning assembly.

17. The printer of claim 16, wherein, when the controller determines that the print head assembly requires cleaning, the print head assembly is configured to adopt a first position relative to the cleaning assembly for purging waste fluid from the print head.

18. The printer claim 17, wherein in the first position the print head is configured to adopt a position substantially above the aperture, wherein the print head is located offset to a centre of the aperture such that the print head nozzles are positioned substantially above the first side of the aperture for ejecting waste fluid from the print head onto a baffle located within the aperture.

19. The printer of claim 18, wherein when the controller determines that all of the waste fluid has been ejected from the print head, the print head assembly is configured to adopt a second position relative to the cleaning assembly for cleaning the print head.

20. The printer of claim 19, wherein in the second position the print head is configured to adopt a position substantially above the aperture, wherein the print head is located offset to a centre of the aperture such that the print head nozzles are positioned substantially above a second side of the aperture above the nozzle for cleaning by the nozzle.

21. The printer of claim 20, wherein when the controller determines that the printer head has been cleaned by the nozzle, a wiper blade of a wiper unit is configured to adopt an extended state in which the wiper blade extends above and away from a surface of a top wall of the tank for contacting the print head in-use, wherein the printer head assembly is configured to displace the print head relative to the wiper blade, such that the wiper blade contacts the print head nozzles so the wiper blade removes any waste fluid and/or debris present on the print head nozzles.

22. A method of cleaning a print head assembly comprising at least one print head having a plurality of print head nozzles for ejecting ink droplets, using the cleaning assembly as recited in claim 1 , the method comprising: purging waste fluid from within the print head into the tank through the aperture having the angled side wall; and vacuuming the print head using the at least one nozzle to clean the print head nozzles.

23. The method of claim 22, further comprising, subsequent to vacuuming the print head, wiping the print head with a wiper blade such as to remove any waste fluid and/or debris present on the print head nozzles.

24. The method of claim 22, wherein purging the waste fluid from within the print head into the tank through the aperture having the angled side wall further comprises the print head adopting a first position substantially above the aperture and ejecting waste fluid from the print head onto the angled side wall.

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25. The method of claim 22, wherein vacuuming the print head using the at least one nozzle to clean the print head nozzles further comprises the print head adopting a second position substantially above the aperture, applying the vacuum force from the nozzle to clean the print head nozzles.

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