The present application claims priority from Japanese Patent Application No. 2019-105314, filed on Jun. 5, 2019, the disclosure of which is incorporated herein by reference in its entirety.
The present disclosure relates to a liquid discharging head provided with a plurality of common channels.
There is known an ink-jet printer provided with individual channels each of which includes a nozzle, a first pressure chamber, a second pressure chamber, and a connecting channel connecting the nozzle and the first and second pressure chambers to one another. A first actuator and a second actuator are provided on the first pressure chamber and the second pressure chamber, respectively. The first pressure chamber communicates with a first common channel, and the second pressure chamber communicates with a second common channel. In a case that ink is circulated, the ink flows from the first common channel to the first pressure chamber, to the connecting channel, to the second pressure chamber, and to the second common channel.
In the above-described ink-jet printer, the first pressure chamber communicates with the first common channel, and the second pressure chamber communicates with the second common channel. Therefore, in the case that the liquid is circulated, there arises any difference in the magnitude of negative pressure between the first and second pressure chambers; by being affected by the difference in the magnitude of the negative pressure, any difference might occur in the deformation amount between the first and second actuators. In such a case, even if a same waveform is applied to the first and second actuators, there is a difference in the initial deformation amount between the first and second actuators, and thus a same deformation amount is less likely to obtain for the first and second actuators, which in turn might cause any disturbance (unstableness) in the discharge of the liquid.
An object of the present disclosure is to provide a liquid discharging head capable of suppressing any difference in the deformation amount between the first and second actuators during the liquid circulation.
According to a first aspect of the present disclosure, there is provided a liquid discharging head including: individual channels aligned in a first direction; and a first common channel and a second common channel extending in the first direction, wherein each of the individual channels includes: a nozzle; a first pressure chamber and second pressure chamber arranged side by side in the first direction; and a connecting channel connecting the nozzle, the first pressure chamber and the second pressure chamber to one another, the first pressure chamber and the second pressure chamber being provided with a first actuator and a second actuator thereon, respectively, the first common channel communicates with the first and second pressure chambers, and the second common channel communicates with the connecting channel.
According to a second aspect of the present disclosure, there is provided a liquid discharging head including: individual channels aligned in a first direction; and a first common channel, a second common channel and a third common channel which extend in the first direction, wherein the first common channel, the second common channel and the third common channel are arranged side by side in a second direction which is a width direction of the first to third common channels, the second common channel being positioned between the first and third common channels in the second direction, each of the individual channels includes a nozzle, a first pressure chamber and second pressure chamber arranged side by side in the second direction, and a connecting channel connecting the nozzle, the first pressure chamber and the second pressure chamber to one another, the first pressure chamber and the second pressure chamber being provided with a first actuator and a second actuator thereon, respectively, the first common channel communicates with the first pressure chamber, the second common channel communicates with the connecting channel, and the third common channel communicates with the second pressure chamber.
Firstly, the overall configuration of a printer 100 provided with a head 1 according to a first embodiment of the present disclosure will be explained, with reference to
The printer 100 is provided with a head unit 1x including four heads 1, a platen 3, a conveying mechanism 4 and a controller 5.
A sheet 9 is placed on the upper surface of the platen 3.
The conveying mechanism 4 has two roller pairs 4a and 4b which are arranged with the platen 3 intervened therebetween in a conveyance direction. In a case that a conveying motor (of which illustration is omitted in the drawings) is driven by control of the controller 5, the roller pairs 4a and 4b rotate in a state that the sheet 9 is sandwiched or pinched therebetween, thereby conveying the sheet 9 in the conveying direction.
The head unit 1x is elongated in a sheet width direction (direction orthogonal to both of the conveyance direction and the vertical direction), and the head unit 1 is of a line system wherein an ink is discharged with respect to the sheet 9 from nozzles 21 (see
The controller 5 has a ROM (Read Only Memory), a RAM (Random Access Memory) and an ASIC (Application Specific Integrated Circuit). The ASIC performs a recording processing, etc., in accordance with a program stored in the ROM. In the recording processing, the controller 5 controls a driver IC and the conveyance motor (both of which are omitted in the illustration of the drawings) of each of the heads 1, based on a recording instruction or recording command (including image data) inputted from an external apparatus or external device such as a PC, and performs recording of an image, etc., on the sheet 9.
Next, the configuration of each of the heads 1 will be explained with reference to
As depicted in
The channel substrate 11 is constructed of 12 (twelve) plates 11A to 11l which are stacked in the vertical direction and adhered to one another. Each of the plates 11a to 11l has a through hole formed therein and constructing a channel. The channel includes a plurality of individual channels 20, a supply channel 31 and a return channel 32.
As depicted in
Each of the supply channel 31 and the return channel 32 extends in the first direction. The supply channel 31 corresponds to a “first common channel” of the present disclosure. The return channel 32 corresponds to a “second common channel” of the present disclosure. In the present embodiment, the supply channel 31 and the return channel 32 are arranged side by side in the vertical direction (third direction: a direction which is the height direction of each of the supply channel 31 and the return channel 32, and which is a direction orthogonal to both of the first and second directions), and overlap with each other in the vertical direction. The supply channel 31 and the return channel 32 have lengths (lengths in the first direction), widths (lengths in the second direction) and heights (lengths in the third direction) which are substantially same to each other, respectively.
The supply channel 31 and the return channel 32 are linked (connected) to each other at one ends thereof, respectively, in the first direction (lower ends thereof in
The supply channel 31 and the return channel 32 communicate with a sub tank (omitted in the drawings) via a supply port 31x and a return port 32x provided on the other ends thereof, respectively, in the first direction (upper ends thereof in
The supply port 31x and the return port 32x are formed on a same side to each other in the first direction with respect to the plurality of individual channels 20, and are arranged side by side in the first direction. In the first direction, the supply port 31x is formed between the plurality of individual channels 20 and the return port 32x. Namely, the spacing distance in the first direction between the return port 32x and the plurality of individual channels 20 is greater than the spacing distance in the first direction between the supply port 31x and the plurality of individual channels 20.
The supply port 31x and the return port 32x are open in the upper surface of the channel substrate 11. Although a filter 31f is provided on the supply port 31x, any filter is not provided on the return port 32x.
The sub tank communicates with a main tank storing the ink, and stores the ink supplied from the main tank thereto. In a case that a pump (omitted in the drawings) is driven by control performed by the controller 5, the ink inside the sub tank is thereby caused to flow into the supply channel 31 from the supply port 31x. The ink inflowed into the supply channel 31 is supplied to each of the plurality of individual channels 20 while moving inside the supply channel 31 from the other end in the first direction (upper end in
As depicted in
As depicted in
As depicted in
As depicted in
The connecting channel 23 connects the nozzle 21 and the first and second pressure chambers 22a and 22b to one another. Specifically, as depicted in
Each of the first and second connecting parts 23a and 23b is a channel having a columnar shape and extending downward from one end in the second direction of one of the first and second pressure chambers 22a and 22b, and is constructed of through holes formed in the plates 11b to 11d, respectively, as depicted in
As depicted in
As depicted in
In the present embodiment, as depicted in
As depicted in
The connecting channel 23 and the nozzle 21 of each of the individual channels 20 belonging to the first individual channel group 20A are positioned on the one side in the second direction with respect to the supply channel 31 and the return channel 32. The connecting channel 23 and the nozzle 21 of each of the individual channels 20 belonging to the second individual channel group 20B are positioned on the other side in the second direction with respect to the supply channel 31 and the return channel 32.
The first inflow channel 24a has one end connected to the other end in the second direction (an end on a side opposite to an end to which the connecting channel 23 is connected) of the first pressure chamber 22a, and the other end connected to the supply channel 31. The second inflow channel 24b has one end connected to the other end in the second direction (an end on a side opposite to an end to which the connecting channel 23 is connected) of the second pressure chamber 22b, and the other end connected to the supply channel 31. The supply channel 31 communicates with the first pressure chamber 22a and the second pressure chamber 22b via the first inflow channel 24a and the second inflow channel 24b, respectively.
The first inflow channel 24a and the second inflow channel 24b are channels connecting the first pressure chamber 24 and the second pressure chamber 22b to the supply channel 31, respectively, and each correspond to a “joining channel” of the present disclosure. In the present embodiment, each of the first and second inflow channel 24a and 24b extends in an oblique direction crossing both of the first and second directions.
As depicted in
As depicted in
The outflow channel 25 is a channel communicating the connecting channel 23 with the return channel 32, and corresponds to a “communicating channel” of the present disclosure. In the present embodiment, the outflow channel 25 extends in the second direction, as depicted in
Each of the first and second inflow channels 24a and 24b and the outflow channel 25 has a width (length in the first direction) which is smaller than a width (length in the first direction) of one of the first and second pressure chambers 22a and 22b, and functions as a throttle.
The ink supplied from the supply channel 31 to each of the plurality of individual channels 20 passes through the first inflow channel 24a and the second inflow channel 24b and inflows into the first pressure chamber 22a and the second pressure chamber 22b, respectively, moves substantially horizontally in the inside of the each of the first and second pressure chambers 22a and 22b, and then inflows into the connecting channel 23. The ink inflowed into the connecting channel 23 passes through the first connecting part 23a and the second connecting part 23b, arrives at the linking part 23c, passes through the extending part 23d and moves downward; a part or portion of the ink is discharged from the nozzle 21, and a remaining part of the ink passes through the outflow channel 25 and inflows into the return channel 32.
In such a manner, the ink is circulated between the sub tank and the channel substrate 11, thereby realizing discharge of air and prevention of increase in the viscosity of the ink in the supply channel 31 and the return channel 32, and further in each of the individual channels 20, which are formed in the channel substrate 11. Further, in such a case that the ink contains a sedimentary component (a component which might sediment or settle; a pigment, etc.), such a sediment component is agitated, which in turn prevents any sedimentation thereof from occurring.
As depicted in
The vibration plate 12a and the common electrode 12b are arranged on the upper surface of the channel substrate 11 (upper surface of the plate 11a), and covers all the first and second pressure chambers 22a and 22b formed in the plate 11a. On the other hand, each of the plurality of piezoelectric bodies 12c and each of the plurality of individual electrodes 12d are provided with respect to one of the first and second pressure chambers 22a and 22b, and are overlapped with one of the first and second pressure chambers 22a and 22b in the third direction.
The common electrode 12b and the plurality of individual electrodes 12d are electrically connected to a driver IC (omitted in the drawings). The driver IC maintains the potential of the common electrode 12b at the ground potential, whereas changes the potential of each of the plurality of individual electrodes 12d. Specifically, the driver IC generates a driving signal based on a control signal from the controller 5, and applies the driving signal to each of the plurality of individual electrodes 12d. By doing so, the potential of each of the plurality of individual electrodes 12d is changed between a5 predetermined driving potential and the ground potential. In this situation, parts or portions in the vibration plate 12a and one of the plurality of piezoelectric bodies 12c, respectively, which are sandwiched between each of the plurality of individual electrodes 12d and one of the first and second pressure chambers 22a and 22b corresponding thereto are deformed so as to project toward one of the first and second pressure chambers 22a and 22b. With this, the volume of one of the first and second pressure chambers 22a and 22b is changed, which in turn applies the pressure to the ink inside one of the first and second pressure chambers 22a and 22b, thereby causing the ink to be discharged from the nozzle 21. The actuator substrate 12 has a plurality of pieces of the actuator 12x corresponding to the first and second pressure chambers 22a and 22b, respectively.
As described above, according to the present embodiment, the supply channel 31 communicates with the first pressure chamber 22a and the second pressure chamber 22b, and the return channel 32 communicates with the connecting channel 23 (see
Further, in the conventional ink-jet printer as described above, the air entering from the nozzle into the individual channel needs to pass through a relatively long route reaching up to the second common channel via the connecting channel and the second pressure chamber. In contrast, in the present embodiment, the air entering from the nozzle 21 into the individual channel 20 does not need to pass through the second pressure chamber 22b until reaching up to the return channel 32, and thus the route via which the air passes is short, which results in the increase in the air discharging efficiency (air discharging performance). Furthermore, the present embodiment is capable of lowering the number of the common channel (the supply channel and the return channel), as compared with a second embodiment (
The length H1 in the third direction from each of the first and second pressure chambers 22a and 22b to the linking part 23c is less than the length H2 in the third direction from the linking part 23c to the nozzle 21 (see
The filter 31f is provided on the supply channel 31, and any filter is not provided on the return channel 32 (see
Next, a head 201 according to a second embodiment of the present disclosure will be explained, with reference to
In the first embodiment (
In the first embodiment (
A channel substrate 211 of the second embodiment is constructed of 9 (nine) plates 211a to 211i which are stacked on top of one another in the third direction and adhered to one another, as depicted in
Each of the two supply channels 231 and the return channel 232 is constructed of through holes formed in the plates 211e and 211f, respectively. Each of the damper chambers 233 corresponding to the two supply channels 231, respectively, is constructed of a recessed part formed in the plate 211g. The bottom part of the recessed part in the plate 211g functions as a damper film 231d of each of the two supply channels 231. The damper chamber 233 corresponding to the return channel 232 is constructed of a recessed part formed in the plate 211d. The bottom part of the recessed part in the plate 211d functions as a damper film 232d of the return channels 232.
As depicted in
Each of the respective individual channels 220 belonging to the first individual channel group 220A communicates with one of the two supply channels 231 (a supply channel 231 on the left side in
Each of the pressure chambers 22a and 22b belonging to the first individual channel group 220A has a part which overlaps, in the third direction, with one of the two supply channels 231 (the supply channel 231 on the left side in
The connecting channel 23 and the nozzle 21 of each of the individual channels 20 belonging to the first individual channel group 220A are positioned, in the second direction, between the one of the two supply channels 231 and the return channel 232. The connecting channel 23 and the nozzle 21 of each of the individual channels 20 belonging to the second individual channel group 220B are positioned, in the second direction, between the other of the two supply channels 231 and the return channel 232.
As described above, according to the second embodiment, although the second embodiment has the configuration of the channel different from that of the first embodiment, the second embodiment satisfies the requirement (the same common channel (supply channel 231) communicates with the first pressure chamber 22a and the second pressure chamber 22b of each of the individual channels 220) similar to that in the first embodiment. With this, the effects similar to those in the first embodiment can be achieved.
Further, in the second embodiment, the damper film 232d (second damper) of the return channel 232 is constructed of the plate 211d constructing each of the first and second inflow channels 24a and 24b (see
Next, a head 301 according to a third embodiment of the present disclosure will be explained, with reference to
In the first embodiment (
One of the two supply channels 331 (a supply channel 331 on the left side in
In the first embodiment (
A channel substrate 311 of the third embodiment is constructed of 8 (eight) plates 311a to 311h which are stacked on top of one another in the third direction and adhered to one another, as depicted in
Each of the two supply channels 331 is constructed of through holes formed in the plates 311e and 311f, respectively. The return channel 332 is formed of a through hole formed in the plate 311e. Each of the damper chambers 333 corresponding to the two supply channels 331, respectively, is constructed of a recessed part formed in the plate 311g. The bottom part of the recessed part in the plate 311g functions as a damper film 331d of each of the two supply channels 331. The damper chamber 333 corresponding to the return channel 332 is constructed of a recessed part formed in the plate 311d. The bottom part of the recessed part in the plate 311d functions as a damper film 332d of the return channels 332.
As depicted in
In the first embodiment (
In the third embodiment, each of the first pressure chamber 22a has a part which overlaps, in the third direction, with one of the two supply channels 331 (the supply channel 331 on the left side in
The first pressure chamber 22a communicates with one of the two supply channels 331 (the supply channel 331 on the left side in
In each of the individual channels 320, the first inflow channel 324a, the second inflow channel 324b, the connecting channel 23, the first pressure chamber 22a and the second pressure chamber 22b are arranged side by side so as to form a row (array) in the second direction, as depicted in
The connecting channel 23 is positioned between the two supply channels 331 in the second direction. The nozzle 21 is positioned between the two supply channels 331 in the second direction, and overlaps with the return channel 332 in the third direction.
First and second connecting parts 23a and 23b of the connecting channel 23 are longer in the third direction than the first and second connecting parts 23a and 23b of the first embodiment (
In the first embodiment (
In the first embodiment (
In the third embodiment, as depicted in
As depicted in
The ink supplied from each of the two supply channels 331 to each one of the plurality of individual channels 320 passes through the first inflow channel 324a or the second inflow channel 324b, inflows into the first pressure chamber 22a or the second pressure chamber 22b, moves substantially horizontally in the inside of the first pressure chamber 22a or the second pressure chamber 22b, and then inflows in to the connecting channel 23. The ink inflowed into the connecting channel 23 passes through the first connecting part 23a and the second connecting part 23b, arrives at one end and the other end in the second direction of the linking part 23c, respectively. Then, the ink moves from the both ends (one end and the other end) toward the center in the second direction of the linking part 23c, and a part or portion of the ink is discharged from the nozzle 21, and a remaining part of the ink passes through the outflow channel 325 and inflows into the return channel 332.
As described above, according to the third embodiment, the first pressure chamber 22a communicates with one of the two supply channels 331, the second pressure chamber 22b communicates with the other of the two supply channels 331, and the connecting channel 23 communicates with the return channel 332 (see
Further, in the conventional ink-jet printer as described above, the air entering from the nozzle into the individual channel needs to pass through a relatively long route until reaching up to the second common channel via the connecting channel and the second pressure chamber. In contrast, in the third embodiment, the air entering from the nozzle 21 into the individual channel 320 does not need to pass through the second pressure chamber 22b until reaching up to the return channel 332, and thus the route via which the air passes is short, which results in the increase in the air discharging efficiency (air discharging performance).
In the individual channel 320, the one end 320a communicating with the one of the two supply channels 331 and the other end 320b communicating with the other of the two supply channels 331 are arranged at the positions which are same to each other in the first direction (see
The outflow channel 325 extends upward from the linking part 23c and reaches the return channel 332 (see
The nozzle 21 is positioned at the location immediately below the linking part 23c (see
The nozzle 21 overlaps, in the vertical direction (third direction), with the outflow channel 325 (see
A filter 31f is provided on the supply channel 331, and any filter is not provided on the return channel 332 (see
The damper film 331d (first damper) is provided on each of the two supply channels 331 (see
The damper film 332d (second damper) of the return channel 332 is constructed of the plate 311d constructing the inflow channels 324a and 324b (see
Next, a head 401 according to a fourth embodiment of the present disclosure will be explained, with reference to
The head 1 of the first embodiment (
Each of the individual channel groups 420A to 420D is constructed of individual channels 420 included in a plurality of individual channels 420 and arranged side by side in the first direction. The four individual channel groups 420A to 420D are arranged side by side in the second direction. In the second direction, the individual channel groups 420B and 420C are positioned between the individual channel groups 420A and 420D.
Individual channels 420 belonging to the individual channel groups 420A and 420B and individual channels 420 belonging to the individual channel groups 420C and 420D communicate with mutually different supply channels 31, respectively, and communicate with mutually different return channels 32, respectively.
A linking part 23c of each of the individual channels 420 is curved in a plane orthogonal to the third direction. Specifically, the linking part 23c of each of the individual channels 420 belonging to the individual channel group 420A has a concave shape receding toward one side in the second direction; the linking part 23c of each of the individual channels 420 belonging to the individual channel group 420B has a concave shape receding toward the other side in the second direction; the linking part 23c of each of the individual channels 420 belonging to the individual channel group 420C has a concave shape receding toward the one side in the second direction; and the linking part 23c of each of the individual channels 420 belonging to the individual channel group 420D has a concave shape receding toward the other side in the second direction.
In the individual channel groups 420B and 420C, the linking parts 23c recede in a direction away from each other. Namely, the linking part 23c of each of the individual channels 420 belonging to the individual channel group 420B has a concave shape receding in a direction away from the individual channel group 420C in the second direction; and the linking part 23c of each of the individual channels 420 belonging to the individual channel group 420C has a concave shape receding in a direction away from the individual channel group 420B in the second direction. The individual channel group 420B corresponds to a “first individual channel group” of the present disclosure, and the individual channel group 420C corresponds to a “second individual channel group” of the present disclosure.
As described above, according to the fourth embodiment, although the fourth embodiment has the configuration of the channel different from that of the first embodiment, the fourth embodiment satisfies the requirement similar to that in the first embodiment. With this, the effects similar to those in the first embodiment can be achieved.
Further, in the fourth embodiment, the linking part 23c of each of the individual channels 420 belonging to the individual channel group 420B has the concave shape receding in the direction away from the individual channel group 420C in the second direction; and the linking part 23c of each of the individual channels 420 belonging to the individual channel group 420C has the concave shape receding in the direction away from the individual channel group 420B in the second direction. In this case, it is possible to arrange the individual channels 420 so that the distance in the second direction between the individual channel group 420B and the individual channel group 420C becomes to be 0 (zero), or that the individual channel group 420B and the individual channel group 420C partially overlap with each other in the first direction (for example, it is possible to insert one end of the linking part 23c of each of the individual channels 420 belonging to the individual channel group 420C into the concave part of the linking part 23c of each of the individual channels 420 belonging to the individual channel group 420B). Consequently, it is possible to realize the densification of the nozzles 21.
Next, a head 501 according to a fifth embodiment of the present disclosure will be explained, with reference to
In the fifth embodiment, connecting parts 23a and 23b of each of individual channels 520 are longer, in the third direction, than the connecting parts 23a and 23b (
In the first embodiment (
In the first embodiment (
In contrast, in the fifth embodiment (
Next, a head 601 according to a sixth embodiment of the present disclosure will be explained, with reference to
In the first embodiment (
Next, a head 701 according to a seventh embodiment of the present disclosure will be explained, with reference to
In the first embodiment (
According to the seventh embodiment, although the seventh embodiment has the configuration of the connecting channel 23 different from that of the first embodiment, the seventh embodiment satisfies the requirement (the same common channel (supply channel 31) communicates with the first pressure chamber 22a and the second pressure chamber 22b of each of the individual channels 720, etc.) similar to that in the first embodiment. With this, the effects similar to those in the first embodiment can be achieved.
[Modifications]
In the foregoing, the embodiments of the present disclosure have been explained. The present disclosure, however, is not limited to or restricted by the above-described embodiments; it is allowable to make a various kind of design changes to the present disclosure, within the scope described in the claims.
In the above-described embodiments, the first common channel is the supply channel, and the second common channel is the return channel. The present disclosure, however, is not limited to or restricted by this configuration. For example, it is allowable that the first common channel is the return channel, and the second common channel is the supply channel. Alternatively, it is allowable that both the first common channel and the second common channel are supply channels. Namely, in the present disclosure, the direction of flow of the liquid in the first and second common channels is not particularly limited. It is similarly applicable also to the third common channel in the third embodiment, and the third common channel may be either one of the supply channel and the return channel.
It is allowable that a filter is provided on the second common channel. It is allowable that any filter is not provided on the first channel.
The third embodiment (
It is allowable that any damper is not provided on the first to third common channels.
The nozzle is not limited to being positioned at the center in the longitudinal direction of the linking part; it is allowable that the nozzle is positioned at any position in the longitudinal direction of the linking part (for example, at one end or the other end in the longitudinal direction of the linking part).
Although the number of the nozzle belonging to each of the individual channels is 1 (one) in the above-described embodiments, it is allowable that the number of nozzle belonging to each of the individual channels may be not less than 2 (two).
The liquid discharging head is not limited to being the head of the line system; it is allowable that the liquid discharging head is a head of a serial system (a system in which the head discharges a liquid from a nozzle toward an object or target of discharge, while the head moves in a scanning direction parallel to the sheet width direction).
The object of discharge is not limited to being a sheet; the object of discharge may be, for example, cloth (fabric), substrate, etc.
The liquid discharged (dischargeable) from the nozzle is not limited to being the ink; it is allowable that the liquid is any liquid (for example, a treating liquid causing a component in the ink to aggregate or deposit; etc.).
The present disclosure is not limited to being applicable to the printer; the present disclosure is applicable also to a facsimile machine, copying machine, a multifunction peripheral, etc. Further, the present disclosure is also applicable to a liquid discharging apparatus usable for a usage different from recording of an image (for example, a liquid discharging apparatus configured to discharge a conductive liquid onto a substrate so as to form a conductive pattern), etc.
Number | Date | Country | Kind |
---|---|---|---|
JP2019-105314 | Jun 2019 | JP | national |
Number | Name | Date | Kind |
---|---|---|---|
10864726 | Miyazawa | Dec 2020 | B2 |
20140078224 | Park | Mar 2014 | A1 |
Number | Date | Country |
---|---|---|
2011-245795 | Dec 2011 | JP |
2014-061695 | Apr 2014 | JP |
Entry |
---|
IP.com search (Year: 2022). |
Number | Date | Country | |
---|---|---|---|
20200384769 A1 | Dec 2020 | US |