Improvements in or relating to a digital printing system

Abstract

A digital printing system (100) for applying a dispensing fluid to a textile, the digital printing system comprising: a reservoir (110) for retaining the dispensing fluid; a dispenser (120) in fluid communication with the reservoir (110) and configured to apply the dispensing fluid to the textile; a processor (130) configured to control the dispenser (120) to optimise the application of dispensing fluid to the textile; and an integral cleaning device (150) configured to eject a cleaning fluid for cleaning a component of the digital printing system (100).

Description

[0001] IMPROVEMENTS IN OR RELATING TO A DIGITAL PRINTING SYSTEM

[0002] FIELD OF THE INVENTION

[0003] The present invention relates to improvements in or relating to a digital printing system and, more specifically, to a digital printing system having an integral cleaning device.

[0004] BACKGROUND TO THE INVENTION

[0005] Manufacturers of dyed and / or treated textiles frequently change the colour of a fluid (i.e., dyestuff) and / or the chemistry of an auxiliary / finishing fluid to be applied to a textile. As such, the fluid within a printing system may require changing. However, the textile industry has strict quality standards regarding defects and performance. In the case of the colour accuracy of a dyed textile, unless all traces of a previously dispensed fluid are removed from within the digital printing system, residual dispensing fluid may cause defects in the subsequently printed textile. Digital dyeing machines with smaller internal components are especially vulnerable to this issue. This is because the dispensed dye droplets are typically applied on a microscopic scale, so a single disperse dye particle, if dissimilar in colour to the rest of the dispensing fluid, can produce a visible dot on the finished textile.

[0006] Traditional methods for cleaning systems for applying a fluid to a textile are laborious and timeconsuming. Whilst this may be acceptable in traditional textile dyeing processes, such practices negate the benefits of newer digital printing processes. It is against this background that the present invention has arisen.

[0007] SUMMARY OF THE INVENTION

[0008] According to the present invention there is provided a digital printing system for applying a dispensing fluid to a textile, the digital printing system comprising: a reservoir for retaining the dispensing fluid; a dispenser in fluid communication with the reservoir and configured to apply the dispensing fluid to the textile; a processor configured to control the dispenser to optimise the application of dispensing fluid to the textile; and an integral cleaning device configured to eject a cleaning fluid for cleaning a component of the digital printing system.

[0009] More specifically, the cleaning device, or an attachment or mounting thereof, may be fixed (i.e., fastened securely) to and / or within the digital printing system. As such, the cleaning device remains a part of the printing system during the normal operation of the system, wherein the 'normal operation' comprises applying the dispensing fluid to the textile. The dispenser may be a flow channel dispenser. The flow channel dispenser may be in the form of a hollow needle suitable for directing a fluid flow. The dispenser may be a piezoactuated dispenser or, more specifically, a digitally controlled piezoactuated dispenser. The piezoactuated dispenser may be operated by a piezoelectric actuator that is controlled by the processor. This enables microdroplets of dispensing fluid to be applied directly onto the textile at a controlled velocity. However, other means of regulating the dispensing fluid being applied to the textile may be used.

[0010] The digital printing system may further comprise a printhead. The printhead may comprise the dispenser. The printhead may be a digital printhead. The printhead may comprise a plurality of dispensers. For example, the printhead may comprise a dispenser array. The dispenser array may extend substantially parallel to a longitudinal axis of the printhead. Each dispenser may be as previously described. Each dispenser may be in fluid communication with the reservoir. Alternatively, each dispenser may be in fluid communication with a separate reservoir. The plurality of reservoirs may each be in fluid communication with a dispensing fluid supply tank. Moreover, in some embodiments, the digital printing system may comprise a plurality of printheads. Each printhead may be as previously described.

[0011] The digital printing system may further comprise a textile transport system. The textile transport system may comprise a plurality of web rollers configured to convey the textile, in use. These rollers may be driven or undriven. The driven roller(s) may be powered via motor. The undriven web roller(s) may be an idler web roller.

[0012] The cleaning fluid may be ejected towards a, some, or all component(s) of the digital printing system. The components of the digital printing system include at least the reservoir, the dispenser, and the cleaning device. Other components may include the printhead and / or elements of a textile transport system, such as a web roller, for example. The cleaning fluid may be configured to displace substantially all dispensing fluid within the system. The velocity and / or flow rate of the ejected cleaning fluid may be variable. This may be controlled by the processor.

[0013] In some embodiments, the cleaning fluid is ejected in the form of a continuous stream. As such, the cleaning device may be configured to jet the cleaning fluid. In some embodiments, the cleaning fluid is ejected in the form of a droplet. As such, the cleaning device may be configured to dispense the cleaning fluid. In some embodiments, the cleaning fluid is ejected in the form of a plurality of droplets. As such, the cleaning device may be configured to spray the cleaning fluid. In each embodiment, the cleaning fluid may be ejected through an orifice within the cleaning device. In use, the cleaning device may eject the cleaning fluid in linear (1-Dimensional); planar (2- Dimensional); or multidimensional (3-Dimensional) ejection patterns. More specifically, a planar ejection pattern may be a wide-angled planar ejection pattern. The wide-angled planar ejection pattern may be a flat fan-shaped ejection pattern. The wide-angled planar ejection pattern may comprise an ejection angle of up to 160 degrees. However, any ejection angle may be used. For example, the ejection angle may be up to 45, 90, 135, or 180 degrees. In some embodiments, the ejection angle may greater than 180 degrees.

[0014] The dispensing fluid may comprise at least one of water, a colourant, an auxiliary chemistry, and a finishing chemistry. As such, the digital printing system may be configured to apply a variety of dispensing fluids, such as a dyestuff, fire retardant and / or a water repellent, to the textile. It is therefore very important to ensure the cleaning device operates efficiently and effectively, as any residue from a previous dispensing fluid (such as a water repellent) may alter the characteristics and / or properties of a subsequent dispensing fluid (such as a dyestuff).

[0015] The cleaning device may comprise a nozzle configured to eject the cleaning fluid. The nozzle, in its simplest form, may be an aperture or an outlet within the cleaning device. In some embodiments, the nozzle may comprise a plurality of apertures. The nozzle may be a spray nozzle. As such, the cleaning fluid may be sprayed from the cleaning device via the spray nozzle. Moreover, in some embodiments, the cleaning device is a spray nozzle.

[0016] The cleaning device may be moveably mounted within the digital printing system. For example, the cleaning device may be moveably mounted on a track or rail. Moreover, the digital printing system may comprise a motor configured to move the cleaning device along the track or rail. As such, the cleaning device may be moveable (in any direction) along an axis and / or across a plane. Consequently, in use, the cleaning device may generate a dynamic fluid ejection pattern resulting from the movement of the cleaning device relative to the region within which it is installed or mounted. This enables a single cleaning device to eject cleaning fluid over a large area of the digital printing system.

[0017] The cleaning device may be rotatably mounted within the digital printing system. As such, the cleaning device may rotate about an axis of rotation. Consequently, in use, the fluid ejection pattern may be a rotating fluid ejection pattern. A rotatable cleaning device (further) enables the cleaning device to eject the cleaning fluid over a large area within the digital printing system. The cleaning device may be rotated by a motor. The motor may be the aforementioned motor or a different motor. Each motor may be of the same or of a different type. The cleaning device may comprise an aperture configured to eject the cleaning fluid along an axis that does not intersect the axis of rotation of the cleaning device. This generates torque about the axis of rotation of the cleaning device. As such, in use, the cleaning device may be rotated by the force of the cleaning fluid being ejected from the aperture. The aperture may be off-centre and / or positioned eccentrically from the axis of rotation of the cleaning device. Alternatively, or in addition, the aperture may be configured to eject cleaning fluid in a non-radial direction with respect to the axis of rotation of the cleaning device. The aperture may be within the nozzle. Alternatively, the aperture may be the nozzle (as previously described). Either way, the aperture may generate a linear (1-Dimensional) ejection pattern; a planar (2-Dimensional) ejection pattern; or a multidimensional (3-Dimensional) ejection pattern. Similarly, in use, the ejection pattern may be dynamic due to the movement of the cleaning device.

[0018] The cleaning device may comprise an elongated spray bar comprising a plurality of apertures configured to eject the cleaning fluid. The elongated spray bar comprising a plurality of apertures may be a perforated conduit. The conduit may be a tube or pipe. The spray bar may comprise an axis of rotation substantially parallel to its longitudinal axis. Again, each aperture may be as previously described. In some embodiments, the cleaning device is an elongated spray bar.

[0019] The cleaning device may be disposed within the reservoir. More specifically, the cleaning device may be mounted to an internal surface of a lid of the reservoir. However, the cleaning device may be disposed within any reservoir or fluid channel used to store or transfer dispensing fluid. Alternatively, or in addition, the cleaning device may be mounted on and / or within any housing or structural element of the digital printing system. For example, the cleaning device may comprise an independent support structure.

[0020] The cleaning device may comprise a plurality of bristles configured to contact at least one surface of the digital printing system. In this context, 'bristle' means any form of non-rigid protrusion, such as a whisker or hair. In some embodiments, the bristles may contact an internal surface of the reservoir. Alternatively, or in addition, the bristles may be configured to contact the dispenser. More specifically, the bristles may contact an inlet and / or outlet of the dispenser. Alternatively, in some embodiments, the bristles may be configured to contact a component of the textile transport system, such as a web roller. In some embodiments, the cleaning device may comprise a sponge and / or wipe configured to contact at least one surface of the digital printing system. The sponge and / or wipe may perform the same function as the bristles. As such, these components may be interchangeable. The digital printing system may comprise a moveable brush configured to scrub at least one surface of the digital printing system. In some embodiments, the brush is integrated within the cleaning device. As such, the bristles may form at least part of the brush. Alternatively, or in addition, the brush may be distinct from the cleaning device. Again, the brush may be replaced with a sponge and / or wipe configured to perform the same function.

[0021] The digital printing system may comprise a motor. The motor may be configured to move the brush. The same motor, or a different motor, may be used to move the cleaning device. The brush may be mounted on a track or rail. The track or rail may be mounted within the digital printing system. For example, the track or rail may be mount on, or adjacent to, a printhead. The track or rail may extend substantially parallel to a longitudinal axis of the printhead. The motor may be configured to move the brush along the track or rail. Alternatively, or in addition, the motor may be configured to rotate the brush, in use.

[0022] The brush may be configured to scrub the dispenser(s). In particular, the brush may be configured to scrub the outlet (i.e., tip) of the dispenser(s). Alternatively, the brush may be configured to scrub an element of the textile transport system, such as a web roller. Multiple brushes may be present. As such, multiple elements, such as dispensers of a printhead and / or web rollers of a textile transport system, may be scrubbed, either simultaneously or sequentially, by different brushes and / or the same brush.

[0023] The cleaning device may be configured to eject a cleaning liquid and a cleaning gas. In other words, the cleaning fluid may comprise a cleaning liquid and a cleaning gas. However, a single cleaning fluid and / or type (i.e., liquid or gas) of fluid may be used. The cleaning liquid may comprise water and / or detergent. The cleaning gas may comprise air. These cleaning fluids may be ejected by the cleaning device simultaneously. The cleaning liquid and cleaning gas may be stored in separate containers. Each cleaning fluid may be supplied to the cleaning device via a non-return valve. This prevents gas from entering the liquid storage container and it prevents liquid from entering the gas storage container. The use of a gas within the cleaning fluid may increase the fluid flow rate, thus pressure, of the fluid being ejected. This may aid movement, and in particular rotation, of the cleaning device.

[0024] The digital printing system may comprise a heating element configured to heat the cleaning fluid prior to it being ejected from the cleaning device. The use of a heated cleaning fluid can improve the cleaning process. For example, the cleaning device may first eject a hot detergent, followed by hot water, and then cold water, before finally ejecting air to help dry the digital printing system. The heating element may be controlled by the processor. The cleaning device may be configured to eject a cleaning liquid and a cleaning gas sequentially. For example, the cleaning device may comprise a first and second fluid supply system. The first fluid supply system may be a liquid fluid supply system. The second fluid supply system may be a gas fluid supply system. Each fluid supply system may comprise a corresponding fluid supply chamber. Each fluid supply system may comprise a non-return valve configured to prevent fluid from returning to the fluid supply chamber. The first and second fluid supply systems may merge into a single cleaning device supply system configured to supply the cleaning device with the cleaning fluid. The two systems may merge upstream of the non-return valve(s). The cleaning liquid may displace (or dilute) the dispensing fluid within the digital printing system and, subsequently, the cleaning gas may displace (or dry) the cleaning liquid within the digital printing system.

[0025] The cleaning device may be digitally controlled. For example, the cleaning device may be controlled by the processor. Alternatively, or in addition, the cleaning device may be controlled by a subsequent processor. As such, the digital printing system may comprise a first processor configured to control the dispenser(s) and a second processor configured to control the cleaning device. The first and second processor may be controlled by a central processing unit (CPU). However, any number of processors may be used. As such, from herein, 'the processor' means any processor, including the first processor, the second processor, and / or the CPU.

[0026] The processor may control the activation, movement, fluid pressure, fluid velocity and / or fluid flow rate of the cleaning device. Alternatively, a plurality of different processors may be used within the system. A single processor may control one or more of the aforementioned variables. The processor may utilise pulse-width-modulation to achieve intermittent "burst" ejections of cleaning fluid, thus enabling high peak fluid flow rates but low time-averaged fluid flow rates. Furthermore, the processor may comprise pre-programmed cleaning cycles tailored to specific component parts or areas of the digital printing system. For example, the processor may activate a first cleaning device in a first larger reservoir for a longer time period than an equivalent second cleaning device in a second smaller reservoir. The processor may also have authority over other components or systems within the digital printing system that may assist operation of the cleaning device. For example, the processor may control a motor configured to move the cleaning device and / or brush.

[0027] The digital printing system may comprise a sensor configured to detect cleaning fluid and / or dispensing fluid within the digital printing system. The data from the sensor may be used to determine the cleanliness of the digital printing system. For example, the sensor may be an ultraviolet (UV) sensor or, more specifically, a UV visible spectrometer. The UV visible sensor may be configured to determine the clarity of the cleaning fluid and / or dispensing fluid within and / or leaving digital printing system. Alternatively, the sensor may be a conductivity sensor. The conductivity sensor may be configured to measure the conductivity of the cleaning fluid and / or dispensing fluid within and / or leaving the printing system. The clarity and / or conductivity of the fluid may be monitored over time.

[0028] In some embodiments, the sensor may be an optical sensor. The optical sensor may be configured to determine the amount of cleaning fluid and / or dispensing fluid within and / or leaving the digital printing system based on the colour of the fluid. During a cleaning process, the fluid within and / or leaving the system may be a mixture of cleaning fluid and / or dispensing fluid. Alternatively, or in addition, the optical sensor may be configured to detect contamination-related defects on a printed / dyed textile as it runs through the digital printing system. Any individual and / or combination of the aforementioned sensors may be used to determine the amount and / or concentration of a dispensing fluid, such as dyestuff, within and / or leaving the printing system.

[0029] The processor may be configured to use data generated by the sensor to optimise the operation of the cleaning device. This optimisation may occur automatically. As such, the processor may utilise data from the sensor to enable closed-loop operation of the cleaning device. The data may be feedback data. The data may be obtained using one or more sensor. The processor may store some or all data from the closed-loop operation of the cleaning device. The stored data may be used to automatically optimise a subsequent operation of the cleaning device. Alternatively, or in addition, the stored data may be used to provide information to a user of the digital printing system.

[0030] The digital printing system may comprise a plurality of sensors. Each sensor may be one of the previously described sensors. The plurality of sensors may comprise sensors of the same and / or different types. Moreover, in some embodiments, a separate sensor may be used to detect each of the dispensing fluid and the cleaning fluid.

[0031] The digital printing system may comprise a plurality of integral cleaning devices configured to eject a cleaning fluid for cleaning a component of the digital printing system. Each cleaning device may be as previously described. Each cleaning device may be configured to clean a different component of the digital printing system. Alternatively, or in addition, a plurality of cleaning devices may be used to clean the same component of the digital printing system. At least one cleaning device may be configured to eject a cleaning liquid and at least one cleaning device may be configured to eject a cleaning gas. Moreover, in some embodiments, at least one cleaning device may be configured to eject a cleaning liquid and a cleaning gas, either simultaneously or sequentially.

[0032] The invention will now be further and more particularly described, by way of example only, with reference to the accompanying drawings. FIGURES

[0033] Figure 1 shows a digital printing system according to the present invention;

[0034] Figure 2 shows a section through the digital printing system shown in figure 1;

[0035] Figure 3 shows a cleaning device comprising a nozzle;

[0036] Figure 4 shows a cleaning device comprising bristles; and

[0037] Figure 5 shows a digital printing system comprising a plurality of an integral cleaning devices.

[0038] DETAILED DESCRIPTION

[0039] Figure 1 shows a digital printing system 100 according to the present invention. More specifically, figure 1 shows a digital printhead 102 located within a digital printing system 100. The digital printing system 100 may further comprise other components, such as a textile transport system (not shown in the accompanying drawings), wherein the textile transport system may comprise a plurality of web rollers configured to convey the textile, in use. The digital printing system 100, and in particular the printhead 102, is configured to apply a dispensing fluid to a textile.

[0040] The digital printing system 100 comprises a reservoir 110 for retaining the dispensing fluid. In the embodiment shown in figure 1, the reservoir 110 is located within the digital printhead 102. However, in other embodiments not shown in the accompanying drawings, the reservoir 110 is located remote from the printhead 102. In fact, in some embodiments, a printhead is not required at all.

[0041] The digital printing system 100 further comprises at least one dispenser 120 in fluid communication with the reservoir 110. The fluid communication between the reservoir 110 and each dispenser 120 may be provide by a fluid channel or conduit. The dispenser 120 is configured to apply the dispensing fluid to the textile. In the embodiment shown in figure 1, the dispenser 120 is a digitally controlled piezoactuated flow channel dispenser in the form of a hollow needle suitable for directing a fluid flow.

[0042] In the embodiment shown in figure 1, the digital printing system 100 comprises a plurality of dispensers 120i.ndisposed within a digital printhead 102. The plurality of dispensers 120i.nform a dispenser array that extends substantially parallel to a longitudinal axis, X, of the printhead 102. Each dispenser 120i.nis as previously described and is in fluid communication with the reservoir 110.

[0043] The digital printing system 100 also comprises a processor 130 configured to control the dispenser(s) 120i.n to optimise the application of dispensing fluid to the textile. For example, the pressure, velocity and / or flow rate of the ejected dispensing fluid may be controlled by the processor 130. The processor 130 also controls the piezoelectric actuation of each dispenser 120i_n.

[0044] In some embodiments, the printhead 102 may comprise a large array of piezoactuated flow channel dispensers 120i.nenclosed within an elongated chamber. For example, there may be up to 720 piezoactuated flow channel dispensers 120i.nenclosed in the chamber. Although, smaller more compact printheads may also be used. The printhead 102 may further comprise a multi-orifice dispensing plate through which the tips of the piezoactuated flow channel dispensers 120i.nare configured to protrude. The chamber may be filled with a fluid of known composition and flow profile such that there is a controlled pressure in the chamber.

[0045] The printhead 102 may further comprise a sealing layer configured to resist fluid flow through the orifices of the multi-orifice dispensing plate. The sealing layer may be configured with a number of openings, each of which is configured to align with the orifices of the multi-orifice dispensing plate through which the tips of the array of flow channel dispensers protrude. The diameter of each opening of the sealing layer through which the flow channel dispensers may be configured to protrude may be smaller than the diameter of the tips of the flow channel dispensers, such that the protruding tips are placed in intimate contact with the edges of the openings of the sealing layer, effectively sealing the chamber of the printhead 102.

[0046] In some embodiments, the printhead 102 may comprise an air dispensing element having a source of compressed air and an air flow controller configured for directing a flow of air in use. As such a flow of air from the air dispensing element may be applied to the tip of one or more flow channel dispenser. In some embodiments, the flow of air is substantially parallel to the direction of travel of the dispensing fluid.

[0047] Furthermore, the digital printing system 100 comprises an integral cleaning device 150 configured to eject a cleaning fluid for cleaning a component of the digital printing system 100. The cleaning device 150 may receive cleaning fluid via an inlet 156 configured to provide fluid communication between the cleaning device 150 and a cleaning fluid supply system (not shown in the accompanying drawings).

[0048] In the embodiment shown in figure 1, the cleaning device 150 is attached to the digital printhead 102 of the digital printing system 100 via a coupling 152. As such, the cleaning device 150 remains a part of the printing system 100 during the normal operation of the system. More specifically, the cleaning device 150, or at least a part thereof, is disposed within the reservoir 110. In particular, and as shown in the embodiment shown in figure 1, the cleaning device 150 may be mounted to the lid 112 of the reservoir 110. In use, the cleaning device 150 may eject cleaning fluid within the reservoir. Figure 2 shows a section through the digital printing system shown in figure 1. As such, the previously described features of figure 1 have been assigned corresponding reference numerals in figure 2 (and throughout the remaining figures). As more clearly shown in figure 2, at least a part of the cleaning device 150 is disposed within the reservoir 110 such that, in use, cleaning fluid may be ejected within the reservoir 110. The cleaning fluid (and / or the dispensing fluid) may be removed from the reservoir via the dispenser(s) 120 and / or via a drain (not shown in the accompanying drawings). The drain may be positioned at the lowest point in the reservoir 110. This enables substantially all the fluid within the reservoir 110 to exit via the drain.

[0049] Figure 3 shows a cleaning device 150 comprising a nozzle 151. The nozzle 151 may be configured to eject the cleaning fluid in the form of a droplet, jet or spray. In its simplest form, the nozzle 151, may be an aperture (or outlet) 153, 154 within the cleaning device 150. However, in some embodiments, as shown in figure 3, the cleaning device 150 comprises a nozzle 151 having a plurality of apertures 153, 154. In particular, the nozzle 151 shown in figure 3 is a spray nozzle. As such, in use, the cleaning fluid may be sprayed from the cleaning device 150 via the spray nozzle 151. Moreover, and as shown in figure 3, the cleaning device 150, in particular the nozzle 151 portion thereof, may be moveably mounted within the digital printing system 100 via rotatable attachment mechanism 155. As such, the cleaning device 150, or more specifically the nozzle 151, may rotate about an axis of rotation, R. Consequently, in use, the fluid ejection pattern may be a rotating fluid ejection pattern.

[0050] In use, the aperture 153, 154 may eject the cleaning fluid along an axis that does not intersect the axis of rotation, R, of the cleaning device 150 and / or nozzle 151. This generates torque about the axis of rotation, R, such that, in use, the nozzle 151 may be rotated by the force of the cleaning fluid being ejected from the aperture. For example, as shown in figure 3, the aperture 153, 154, or at least a part thereof, may be off-centre and / or positioned eccentrically from the axis of rotation, R, of the cleaning device.

[0051] Figure 4 shows a cleaning device 150 comprising a plurality of bristles 158. The bristles 158 are configured to contact at least one surface of the digital printing system 100. In the embodiment shown in figure 4, the bristles 158 are configured to contact the dispenser(s) 120i.n. More specifically, the bristles 158 are configured to contact an outlet (or tip) of each dispenser 120i_n. The cleaning device 150 having bristles 158 may further eject a cleaning fluid for cleaning a component, in this case the dispenser(s) 120i.n, of the digital printing system 100. However, in some embodiments, the digital printing system 100 comprises a plurality of cleaning devices 150, wherein at least one cleaning device 150 is configured to eject a cleaning fluid and at least one cleaning device 157 comprises a plurality of bristles 158 configured to contact at least one surface of the digital printing system 100. The cleaning device 157 comprising bristles 158 may be a brush. In some embodiments, the brush 157 may not eject a cleaning fluid.

[0052] As shown in figure 4, the cleaning device 150, 157 may be moveably mounted on a track or rail 159. In some embodiments, as shown in figure 4, the track or rail 159 is mount on the printhead 102 and extends substantially parallel to the longitudinal axis, X, thereof. The digital printing system 100 may further comprise a motor (not shown in the accompanying drawings) configured to move the cleaning device 150, 157 along the track or rail 159. As such, the bristles 158 may be configured to scrub at least one surface, in this case the dispenser(s) 120i.n, of the digital printing system.

[0053] In some embodiments, the processor 130 controls the motor, thus the movement of the cleaning device 150, 157. Alternatively, a separate processor may be used. Moreover, the cleaning device 150, 157 may be digitally controlled. In particular, the cleaning device 150, 157 may be controlled by the processor 130. For example, the pressure, velocity and / or flow rate of the ejected cleaning fluid may be controlled by the processor 130. Alternatively, or in addition, the cleaning device 150, 157 may be controlled by a subsequent processor (not shown in the accompanying drawings). As such, the digital printing system 100 may comprise a first and second processor, although any number of processors may be used.

[0054] Figure 5 shows a digital printing system 100 comprising a plurality of an integral cleaning devices 150. More specifically, figure 5 shows a digital printhead 102 located within a digital printing system 100, wherein the digital printhead 102 comprises a plurality of an integral cleaning devices 150. Each integral cleaning device 150 may be configured to eject a cleaning fluid for cleaning a component of the digital printing system, such as the reservoir 110. Each cleaning device 150 may be as previously described.

[0055] In some embodiments, not shown in the accompanying drawings, the digital printing system 100 comprises a sensor configured to detect cleaning fluid and / or dispensing fluid within and / or leaving the digital printing system. The data from the sensor may be used to determine the cleanliness of the digital printing system. The sensor may be an ultraviolet (UV) sensor; a UV visible spectrometer; a conductivity sensor; or an optical sensor.

[0056] The processor 130, or an alternative processor, may utilise data generate by the sensor to enable closed-loop operation of the cleaning device 150. The processor may store some or all data from the closed-loop operation of the cleaning device. The stored data may be used to automatically optimize a subsequent operation of the cleaning device. Alternatively, or in addition, the stored data may be used to provide information to a user of the digital printing system. Various further aspects and embodiments of the present invention will be apparent to those skilled in the art in view of the present disclosure, "and / or" where used herein is to be taken as specific disclosure of each of the two specified features or components with or without the other. For example, "A and / or B" is to be taken as specific disclosure of each of (i) A, (ii) B and (iii) A and B, just as if each is set out individually herein.

[0057] Unless context dictates otherwise, the descriptions and definitions of the features set out above are not limited to any particular aspect or embodiment of the invention and apply equally to all aspects and embodiments that are described. It will further be appreciated by those skilled in the art that although the invention has been described by way of example with reference to several embodiments, it is not limited to the disclosed embodiments and that alternative embodiments could be constructed without departing from the scope of the invention as defined in the appended claims.

Claims

CLAIMS1. A digital printing system for applying a dispensing fluid to a textile, the digital printing system comprising: a reservoir for retaining the dispensing fluid; a dispenser in fluid communication with the reservoir and configured to apply the dispensing fluid to the textile; a processor configured to control the dispenser to optimise the application of dispensing fluid to the textile; and an integral cleaning device configured to eject a cleaning fluid for cleaning a component of the digital printing system.

2. The digital printing system according to any preceding claim, wherein the cleaning device comprises a nozzle configured to eject the cleaning fluid.

3. The digital printing system according to any preceding claim, wherein the cleaning device is moveably mounted within the digital printing system.

4. The digital printing system according to any preceding claim, wherein the cleaning device is rotatably mounted within the digital printing system.

5. The digital printing system according to claim 4, wherein the cleaning device comprises an aperture configured to eject the cleaning fluid along an axis that does not intersect the axis of rotation of the cleaning device.

6. The digital printing system according to any preceding claim, wherein the cleaning device comprises an elongated spray bar comprising a plurality of apertures configured to eject the cleaning fluid.

7. The digital printing system according to any preceding claim, wherein the cleaning device is disposed within the reservoir.

8. The digital printing system according to any preceding claim, wherein the cleaning device comprises a plurality of bristles configured to contact at least one surface of the digital printing system.

9. The digital printing system according to any preceding claim, further comprising a moveable brush configured to scrub at least one surface of the digital printing system.

10. The digital printing system according to any preceding claim, wherein the cleaning device is configured to eject a cleaning liquid and a cleaning gas.

11. The digital printing system according to any preceding claim, further comprising a heating element configured to heat the cleaning fluid prior to it being ejected from the cleaning device.

12. The digital printing system according to any preceding claim, wherein the cleaning device is configured to eject a cleaning liquid and a cleaning gas sequentially.

13. The digital printing system according to any preceding claim, wherein the cleaning device is digitally controlled.

14. The digital printing system according to any preceding claim, further comprising a sensor configured to detect cleaning fluid and / or dispensing fluid within the digital printing system.

15. The digital printing system according to claim 14, wherein the processor is configured to use data generated by the sensor to optimise the operation of the cleaning device.

16. The digital printing system according to any preceding claim, comprising a plurality of integral cleaning devices configured to eject a cleaning fluid for cleaning a component of the digital printing system.

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