Printing devices, such as inkjet printers print on a print medium by spraying ink on the print medium. Ink is supplied to a printhead of the printer which performs a printing operation on the print medium. Print quality may depend on ink supplied to the printhead,
The following detailed description references the drawings, wherein:
A printing device, such as an inkjet printer includes a printhead for printing on a print media and ink cartridges or regulators for providing ink to the printhead. An ink regulator has a capacity for holding ink and has at least one outlet connected to the printhead for flowing ink to the printhead. The printhead and the ink regulator may be mounted on a carriage of the printer. The printhead and the ink regulator may move along with the carriage during printing.
In printers for home use, also called on-axis printers, which usually have a low print volume demand, the ink regulator is generally a single source of ink, Therefore, every time ink in the ink regulator is depleted, the ink regulator has to be replaced which interrupts the printing operations and increases downtime of the printer. Further, having an ink regulator of a larger size to enhance the ink holding capacity may result in increase in weight of the ink regulator and in turn increase in weight of the carriage. A heavier carriage may be unstable during its movement while printing. Although, a heavier carriage may be stabilized by use of carriage stabilizing means, use of such means may, however, result in higher loading or power consumption, and thereby may lead to heating up of motors and other electrical components inside the printer. Further, having an ink regulator of a larger size results in increase in size of the printer which affects the modularity of the on-axis printers and makes the printers cost intensive.
Printers for commercial use, also called off-axis printers, which usually have a high print volume demand, include an ink reservoir positioned inside the printer away from the carriage. The ink reservoir acts as a source of ink from where ink can be transferred to the ink regulator when ink in the ink regulator is depleted. One end of the ink regulator is connected to the printhead and other end is connected to the ink reservoir through a pipe or tube. When ink in the ink regulator is depleted, ink from the ink reservoir may be pumped through the pipe to the ink regulator. Thus, in off-axis printers there is a permanent connection between the ink regulator and the ink reservoir. During printing, when the ink regulator moves along with the carriage, the tube connecting the ink regulator with the ink reservoir is subjected to twist and bend forces because of the movement of the carriage. Twisting of the tube may lead to instability in movement of the carriage, may block flow of ink through the tube, and thereby adversely affect print quality. Also, due to the forces acting on the tube, there may be wear and tear of the tube which may reduce longevity of the tube and increase chances of faults due to damage of the tube. Further, the forces acting on the tube may also result in leaking of the tube and thereby lead to ink spillage and loss of ink.
In the present subject matter, approaches for an ink supply assembly for a printing device have been discussed. The ink supply assembly includes a fluidic interconnect, couplable to an ink reservoir, which can be moved to engage with an inlet port of an ink regulator to supply and fill ink from the ink reservoir into the ink regulator when the ink regulator is low on ink. An inlet port refers to an opening in the ink regulator which is configured to receive the fluidic interconnect for flowing ink into the ink regulator. When a prescribed volume of ink has been supplied and filled into the ink regulator, the fluidic interconnect can be moved to disengage from the inlet port. Thus, the ink supply assembly enables a dynamic make-break connection between the ink reservoir and the ink regulator.
The dynamic engagement and disengagement of the ink regulator with the ink reservoir through movement of the fluidic interconnect, in accordance with the present subject matter, avoids having a permanent connection between the ink regulator and the ink reservoir, as present in the off-axis printers. Thus, the use of tubes or pipes for forming the permanent connection is eliminated. Without tubes being used for the permanent connection, carriage instability associated with twisting of tubes may be reduced and issue of blocking of ink flow through the tubes is eliminated. Thus, print quality may be improved. Also, chances of leakage of the tubes and ink spillage are eliminated. Further, with the present subject matter, in contrast to the on-axis printers discussed earlier, the ink regulator need not be replaced every time ink in the ink regulator is depleted. Rather, when the ink regulator is low on ink, a fluidic interconnect coupled to the ink reservoir gets engaged with the inlet port of the ink regulator and thereby ink can be refilled in the ink regulator. Once the ink regulator is refilled, the fluidic interconnect may be disengaged from the inlet port.
The following detailed description refers to the accompanying drawings. Wherever possible, the same reference numbers are used in the drawings and the following description to refer to the same or similar parts. While several examples are described in the description, modifications, adaptations, and other implementations are possible. Accordingly, the following detailed description does not limit the disclosed examples. Instead, the proper scope of the disclosed examples may be defined by the appended claims.
The ink supply assembly 100 includes a drive rack 102 and a fluidic interconnect 104 mounted on the drive rack 102. The drive rack is a mechanical arrangement for holding fluidic interconnects and for moving the fluidic interconnects within the printing device. In an example implementation, the fluidic interconnect 104 is a linearly extending rigid conduit for transporting ink. In an example implementation, the fluidic interconnect 104 may be a hollow metallic needle. The fluidic interconnect 104 is couplable to an ink reservoir 106 of the printing device. The ink reservoir 106 may include various chambers for holding inks of different colors. In an example implementation, the fluidic interconnect 104 may be connected to the chambers of the ink reservoir 106. Although in
When the ink regulator 108 has a volume of ink less that a predefined threshold, the drive rack 102 is operated to move the fluidic interconnect 104 in a first direction, as indicated by arrow A, to engage the fluidic interconnect 104 with the inlet port 110 of the ink regulator 108. This engagement between the fluidic interconnect 104 and the inlet port 110 enables ink from the ink reservoir 106 to be supplied and filled into the ink regulator 108.
In an example implementation, after supplying and filling the ink in the ink regulator 108, the drive rack 102 is operated to move the fluidic interconnect 104 in a second direction, as indicated by arrow B, to disengage the fluidic interconnect 104 from the inlet port 110, where the second direction is different from the first direction. In an example implementation, the second direction is opposite to the first direction as also depicted through arrows A and B. As explained above, the connection between the ink regulator 108 and the ink reservoir 106 is not a permanent connection rather it is a breakable connection which can be formed or disconnected depending on the level of ink in the ink regulator 108.
As shown in
In an example implementation, the drive rack 202 includes a plurality of guide pins 208 to align the fluidic interconnect 206 with an inlet port of an ink regulator, for example, the inlet port 110 of the ink regulator 108. In an example implementation, each of the guide pins 208 may be formed from metal and may be integral to the drive rack 202.
The ink supply assembly 200 further includes an ink circulation unit 210 coupled to an end of the fluidic interconnect 206. The ink circulation unit 210, as shown, includes a pump 212 and an ink reservoir 214. In an example implementation, an end of the fluidic interconnect 206 may be connected to the ink reservoir 214 through tubes. The ink reservoir 214 may have multiple chambers having different colors of ink and the fluidic interconnect 206 may be connected to one of such chambers.
In an example implementation, the pump 212 may be operated to flow ink from the ink reservoir 214 through the fluidic interconnect 206 and into an ink regulator, for example, the ink regulator 108. In an example implementation, the pump 212 may also be operated to draw out a mixture of air and ink from the ink regulator. Thus, the ink circulation unit 210 enables a continuous flow of ink through the ink supply assembly 200, to provide ink circulation as in continuous ink supply systems (CISS).
The ink supply assembly 200 further includes a drive controller 216 coupled to the drive rack 202. In an example implementation, the drive controller 216 may be implemented as hardware, such as a processor(s) or through logical instructions or a combination thereof. The processor(s) may be implemented as microprocessors, microcomputers, microcontrollers, digital signal processors, central processing units, state machines, logic circuitries, and/or any devices that manipulate signals based on operational instructions. The drive controller 216 may perform various functions for the purpose of triggering motion of the drive rack 202, in accordance with the present subject matter. In an example implementation, the drive controller 216 may be coupled to the CNC stages which may be mechanically coupled to the drive rack 202, through gear assemblies (not shown), to enable movement of the drive rack 202. The drive shafts 204 guide and control the movement of the drive rack 202.
The drive controller 216 is operable to trigger movement of the drive rack 202 in a first direction, as indicated by arrow A, when the ink regulator, for example the ink regulator 108, has a volume of ink less than a predefined threshold. In an example implementation, the predefined threshold is 5%-10% of the full capacity of the ink regulator. When the drive rack 202 is moved in the first direction, the plurality of guide pins 208 enable alignment of the fluidic interconnect 206 with an inlet port of an ink regulator, for example, the inlet port 110 of the ink regulator 108. The movement of the drive rack 202 in the first direction is to engage the fluidic interconnect 206 with the inlet port of the ink regulator.
When a prescribed volume of ink has been supplied to the ink regulator (not shown), the drive controller 216 is operable to trigger movement of the drive rack 202 in the second direction, as indicated by arrow B. In an example implementation, the prescribed volume is 90%-95% of the full capacity of the ink regulator. The movement of the drive rack 202 in the second direction is to dis-engage the fluidic interconnect 206 from the inlet port of the ink regulator.
The image forming unit 300 includes an ink regulator 304 mounted on the carriage 302. The ink regulator 304 may be coupled to the printhead and may provide ink to the printhead for printing. The ink regulator 304 has an inlet port 306. In an example implementation, the ink regulator 304 may also have an outlet port (not shown). The inlet port 306 and the outlet port may be configured to receive a fluidic interconnect, for example the fluidic interconnect 104 of
The image forming unit 300 further includes an ink level manager 308 coupled to the ink regulator 304. In an example implementation, the ink level manager 308 may be implemented as hardware, such as a processor(s) or through logical instructions or a combination thereof. The processor(s) may be implemented as microprocessors, microcomputers, microcontrollers, digital signal processors, central processing units, state machines, logic circuitries, and/or any devices that manipulate signals based on operational instructions. The ink level manager 308 may perform various functions for the purpose of determining a level of ink in the ink regulator 304 and accordingly generate control signals for operating different components/units of the printing device.
The ink level manager 308 is coupled to an ink supply assembly 310 of the printing device. The ink supply assembly 310 may include features of the ink supply assembly 200. In an example implementation, the ink level manager 308 may be coupled to a drive controller of the ink supply assembly, for example, the drive controller 216 of the ink supply assembly 200 of
In an example implementation, a level/volume of ink in the ink regulator 304 may be determined by the ink level manager 308. In an example implementation, sensors (not shown) may be coupled to the ink regulator 304 and the output of such sensors may be provided to the ink level manager 308. The ink level manager 308 may determine whether the ink regulator 304 has a volume of ink upto a predefined threshold, based on the output of the sensors. In an example implementation, the volume of ink in the ink regulator 304 may be determined by the ink level manager 308 by monitoring number of drops of ink being ejected from the ink regulator 304. Based on the number of drops of ink being ejected and an average volume of each drop of ink, the ink level manager 308 may determine the total volume of ink being ejected and estimate the volume of ink remaining in the ink regulator 304. In another example implementation, the ink level manager 308 may determine the volume of ink in the ink regulator 304 based on flowrate of a pump, for example the pump 212, which is used to transfer ink from an ink reservoir to the ink regulator 304.
When the ink level manager 308 determines that the ink regulator 304 has a volume of ink less than a predefined threshold, the ink level manager 308 sends a first signal to the ink supply assembly 310. In an example implementation, the predefined threshold is 5%-10% of the full capacity of the ink regulator 304 and value of the predefined threshold may be preset in the ink level manager 308. The first signal is indicative of triggering engagement of a fluidic interconnect of an ink supply assembly, for example the fluidic interconnect 206 of the ink supply assembly 310, with the inlet port 306 to supply ink to the ink regulator 304. In an example implementation, the ink level manager 308 may send the first signal to a drive controller of an ink supply assembly, for example the drive controller 216 of the ink supply assembly 200 of
When the ink level manager 308 determines that a prescribed volume of ink has been supplied to the ink regulator, the ink level manager 308 sends a second signal to the ink supply assembly 310. In an example implementation, the prescribed volume of ink is 90% to 95% of the full capacity of the ink regulator 304 and value of the prescribed volume of ink may be preset in the ink level manager 308. The second signal is indicative of triggering disengagement of the fluidic interconnect from the inlet port 306. In an example implementation, the ink level manager 308 may send the second signal to a drive controller of an ink supply assembly, for example the drive controller 216 of the ink supply assembly 200 of
In an example implementation, a sealing assembly, similar to the sealing assembly 404 may also be positioned inside the ink regulator 304 of
With reference to
The printing device 500 also includes a drive rack 508 similar to the drive rack 102 of
When at least one of the ink regulators, 504-1 to 504-4, has a volume of ink less than a predefined threshold, the drive rack 508 is operated to move the fluidic interconnect assembly 510 in a first direction, as indicated by arrow A, to engage each of the fluidic interconnects, 510-1 to 510-4, with the respective inlet ports 506-1 to 506-2 of the ink regulators 504-1 to 504-4, In an example implementation, the predefined threshold is about 5%-10% of the full capacity of the ink regulator. This engagement between of the fluidic interconnects and the inlet ports enables ink to be supplied from the ink reservoir 512 and to be filled into the at least one ink regulator which has the volume of ink less than the predefined threshold.
In an example implementation, after supplying the ink in the at least one ink regulator, the drive rack 508 is operated to move the fluidic interconnect assembly 510 in a second direction, as indicated by arrow B, to disengage the fluidic interconnects, 510-1 to 510-4, respective inlet ports 506-1 to 506-2 of the ink regulators 504-1 to 504-4. In an example implementation, the second direction is opposite to the first direction as also depicted through arrows A and B.
Each of the ink regulators 604-1, 604-2, 604-3, and 604-4 has corresponding inlet ports 606-1, 606-2, 606-3, and 606-4, respectively. Further, each of the ink regulators 604-1, 604-2, 604-3, and 604-4 has corresponding outlet ports 608-1, 608-2, 608-3, and 608-4, respectively. Ink is flowed into the ink regulators 604-1 to 604-4 through their respective inlet ports 606-1 to 606-4 and a mixture of air and ink may be drawn out from the ink regulators 604-1 to 604-4 through their respective outlet ports 608-1 to 608-4.
With reference to
The printing device 600 also includes an ink level manager 610 similar to the ink level manager 308 of
The printing device 600 also include the features of the ink supply assembly 200 illustrated through
As shown in
During operation of the printing device 600, the ink level manager 610 can determine whether at least one of the ink regulators, 604-1 to 604-4, is low on ink, i.e., it has a volume of ink less that a predefined threshold. In an example implementation, the predefined threshold may be 5%-10% of the full capacity of the ink regulator and may be preset in the ink level manager 610. The ink level manager 610 can determine the level/volume of ink in the ink regulators 604-1 to 604-4 through use of sensors or through other techniques, as previously mentioned in the description of
Upon determining that the ink regulator 604-1 is low on ink, the ink level manager 610 may generate a first signal. The first signal is indicative of triggering engagement of the first set of fluidic interconnects 614-1 to 614-4, with the inlet ports 606-1 to 606-4 of the ink regulators 604-1 to 604-4 and engagement of the second set of fluidic interconnects, 614-1 to 614-4, with the outlet ports, 608-1 to 608-4, of the ink regulators, 604-1 to 604-4.
In an example implementation, the first signal may be sent to the drive controller 216 coupled to the drive rack 612. The drive controller 216, on receiving the first signal, may trigger movement of the drive rack 612 in a first direction, indicated by arrow A. As the drive rack 612 moves in the first direction, the fluidic interconnect assembly 614 is also moved in the first direction to engage the fluidic interconnects 614-1 to 614-8 with the corresponding inlet/outlet ports of the ink regulators 604-1 to 604-4.
In an example implementation, the ink regulator assembly 604 comprises a housing (not shown) having a plurality of locator holes or openings adapted to receive the guide pins 616. When the fluidic interconnect assembly 614 is moved in the first direction each of the plurality of guide pins 616 pass through a locator hole (not shown), from the plurality of locator holes, to align the fluidic interconnects, 614-1 to 614-8, with inlet or outlet ports of corresponding ink regulators 604-1 to 604-4.
In an example implementation, the guide pins 616 may align the first set of fluidic interconnects, 614-1 to 614-4, with the corresponding inlet ports, 606-1 to 606-4, of the ink regulators, 604-1 to 604-4. The guide pins 616 also align the second set of fluidic interconnects, 614-5 to 614-8, with the corresponding outlet ports, 608-1 to 608-4, of the ink regulators, 604-1 to 604-4.
Once the fluidic interconnects 614-1 to 614-8 are aligned with corresponding inlet/outlet ports of the, movement of the drive rack 612 further in the first direction, causes the first set of fluidic interconnects, 614-1 to 614-4, to pass through the inlet ports 606-1 to 606-4 and the second set of fluidic interconnects, 614-5 to 614-8, to pass through the outlet ports 608-1 to 608-4.
The technique in which the fluidic interconnects engage/disengage with the ports is described with reference to the fluidic interconnect 614-1 which passes through the inlet port 606-1 of the ink regulator 604-1. The other fluidic interconnects 614-2 to 614-8 may engage with the ports of the ink regulator in a similar fashion. During engagement of the fluidic interconnect 614-1 with the inlet port 606-1, as the fluidic interconnect 614-1 passes through the inlet port 606-1, the stopper element 410 interfaces with the fluidic interconnect 614-1. The stopper element 410 is moved by the fluidic interconnect 614-1, such that the stopper element 410 biases or compresses the resilient element 406, as shown in
After engagement of the fluidic interconnects with the ports of the ink regulators, the ink level manager 610 may operate the pump 212 of the ink circulation unit 210 to supply a prescribed volume of ink to the ink regulator 604-1. In an example implementation, the prescribed volume may be 90%-95% of the full capacity of the ink regulator 604-1 and may be preset in the ink level manager 610 at the time of assembly of the printing device 600. In an example implementation, when the pump 212 is operated, the pump 212 may drive ink, as indicated by link C, from the ink reservoir 214 through the fluidic interconnect 614-1 into the ink regulator 604-1 and may draw out a mixture of air and ink, as indicated by link D, from the ink regulator 604-1, through the fluidic interconnect 614-5, into the ink circulation unit 210.
When the ink level manager 610 determines that the prescribed volume of ink has been supplied to the ink regulator 604-1, the ink level manager 610 may generate a second signal. The second signal is indicative of triggering disengagement of the first set of fluidic interconnects 614-1 to 614-4, from the inlet ports 606-1 to 606-4 of ink regulators 604-1 to 604-4 and disengagement of the second set of fluidic interconnects, 614-5 to 614-8, from the outlet ports, 608-1 to 608-4, of the ink regulators, 604-1 to 604-4.
In an example implementation, the second signal may be sent to the drive controller 216 coupled to the drive rack 612. The drive controller 216, on receiving the second signal, may trigger movement of the drive rack 612 in a second direction, indicated by arrow B. As the drive rack moves in the second direction, the fluidic interconnect assembly 614 is also moved in the second direction to disengage the fluidic interconnects, 614-1 to 614-8, from inlet/outlet ports of the corresponding ink regulators.
During disengagement of the fluidic interconnect 614-1 from the inlet port 606-1, as the fluidic interconnect 614-1 moves in the second direction, the resilient element 406 gets unbiased or relaxed thereby moving the stopper element 410 towards the inlet port 606-1 to seal the inlet port 606-1.
Although implementations of ink supply assembly for a printing device, image forming unit of a printing device, and printing device having such ink supply assembly and image forming unit have been described in language specific to structural features and/or methods, it is to be understood that the present subject matter is not limited to the specific features or methods described. Rather, the specific features and methods are disclosed and explained as example implementations for ink supply assembly for a printing device, image forming unit of a printing device, and printing device having such ink supply assembly and image forming unit.
Filing Document | Filing Date | Country | Kind |
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PCT/US2017/029773 | 4/27/2017 | WO | 00 |