Patent Application
20230117107
The present application is based on, and claims priority from JP Application Serial Number 2021-169380, filed Oct. 15, 2021, the disclosure of which is hereby incorporated by reference herein in its entirety.
Embodiments of the present disclosure relate to a tank unit configured to contain liquid and a liquid ejecting apparatus equipped therewith.
JP-A-2020-082536 discloses an ink-jet printer as an example of a liquid ejecting apparatus that includes a liquid ejecting head configured to eject liquid such as ink. A liquid ejecting apparatus of this kind includes a tank unit configured to store liquid. A liquid container such as a cartridge is detachably attached to the tank unit. The tank unit is configured such that liquid supplied from the liquid container flows into it and the liquid flows out of it toward a liquid ejecting head configured to eject the liquid. The liquid ejecting head ejects the liquid supplied from the tank unit.
The tank unit disclosed in JP-A-2020-082536 has two reservoir chambers. One of them is a first chamber configured to store the liquid having flowed in from the liquid container. The other is a second chamber configured to store the liquid having flowed in from the first chamber. The liquid flows from the second chamber into the liquid ejecting head. The tank unit disclosed in JP-A-2020-082536 further includes a replenishment valve, a liquid surface sensor, and a circulation pump, which are controlled by a controller.
However, in the liquid ejecting apparatus disclosed in JP-A-2020-082536, in order to adjust the liquid surface of the two reservoir chambers into an appropriate level, complex supply control by means of the replenishment valve, the liquid surface sensor, and the circulation pump is required. Therefore, a tank unit and a liquid ejecting apparatus that make it possible to adjust the liquid surface of the two reservoir chambers into an appropriate level with a simple structure have been awaited.
A tank unit according to a certain aspect of the present disclosure is configured such that liquid supplied from a liquid container flows into it and the liquid flows out of it toward a liquid ejecting head configured to eject the liquid. The tank unit includes: a first inlet portion via which the liquid supplied from the liquid container flows in; a first chamber configured to store the liquid that flows in via the first inlet portion; a first opening-to-atmosphere portion configured to open an inside of the first chamber to atmosphere; an outlet flow passage to which one end is connected to the first chamber; a second chamber connected to the other end of the outlet flow passage and configured to store the liquid supplied from the first chamber; a second opening-to-atmosphere portion configured to open an inside of the second chamber to atmosphere; and an on-off valve configured to open and close the outlet flow passage, wherein the first inlet portion is connected to the first chamber via an opening portion at some midpoint in a vertical direction of the first chamber.
A liquid ejecting apparatus according to a certain aspect of the present disclosure includes a liquid ejecting head configured to eject liquid; the above tank unit; a supply flow passage that provides communication between the outlet portion and the liquid ejecting head; and a collection flow passage that provides communication between the liquid ejecting head and second inlet portion.
With reference to the accompanying drawings, a tank unit according to some exemplary embodiments of the present disclosure, and a liquid ejecting apparatus equipped therewith, will now be explained. The liquid ejecting apparatus disclosed herein is, for example, an ink-jet printer that performs printing by ejecting ink, which is an example of liquid, onto a medium such as paper.
In the drawings, it is assumed that a liquid ejecting apparatus 11 is installed on a horizontal plane, and, based on this assumption, the direction of gravity is indicated by a Z axis, and the directions along the horizontal plane are indicated by an X axis and a Y axis. The X, Y, and Z axes are orthogonal to one another. When the user stands in front of the liquid ejecting apparatus 11 in a facing manner, the Y axis represents the direction of the depth of the liquid ejecting apparatus 11, and the X axis represents the direction of the width of the liquid ejecting apparatus 11.
As illustrated in
The liquid ejecting apparatus 11 includes a control portion 19, which controls various kinds of operation performed in the liquid ejecting apparatus 11. The control portion 19 can be configured as circuitry that includes: (1) one or more processors configured to operate in accordance with computer programs (software), (2) one or more specific-purpose hardware circuits such as specific-purpose hardware (application specific integrated circuit (ASIC)) configured to perform at least a part of various kinds of processing, or (3) a combination of them. The processor includes a CPU and a memory such as a RAM and a ROM, etc. Program codes or commands configured to cause the CPU to perform processing are stored in the memory. The “memory”, namely, a computer-readable medium, encompasses every kind of available medium that is accessible by a general-purpose or specific-purpose computer.
The liquid ejecting apparatus 11 includes a tank unit 26. The tank unit 26 may include an attachment portion 28 to which one or more liquid containers 24 can be detachably attached. The attachment portion 28 may have a plurality of slots corresponding respectively to the plurality of liquid containers 24. The attachment portion 28 has an insertion opening 28o through which the liquid containers 24 are configured to be inserted. The insertion opening 28o is, for example, open at the front of the liquid ejecting apparatus 11. In this case, for example, the liquid containers 24 are configured to be inserted through the insertion opening 28o in the direction along the Y axis from the front of the liquid ejecting apparatus 11. The liquid ejecting apparatus 11 may include a non-illustrated cover configured to cover the insertion opening 28o. The cover may be movable between a position for covering the insertion opening 28o and a position for exposing the insertion opening 28o.
Plural different kinds of liquid, for example, plural kinds of ink different in color from one another, may be contained in the plurality of liquid containers 24 (24C, 24M, 24Y, and 24K) respectively. For example, cyan ink, magenta ink, yellow ink, and black ink are contained in the liquid containers 24C, 24M, 24Y, and 24K respectively. The amount of liquid contained in the plurality of liquid containers 24 may be different between any two or more of them. For example, the amount of liquid contained in the liquid container 24K, namely, black ink, may be larger than the amount of liquid contained in the liquid container 24C, 24M, 24Y. The width of the liquid container 24K, namely, its length along the X axis, may be greater than that of the liquid container 24C, 24M, 24Y. The direction in which the liquid containers 24 can be inserted into the tank unit 26 is not limited to the direction along the Y axis. It may be the direction along the X axis, the direction along the Z axis, an oblique direction intersecting with at least one of the X, Y, and Z axes at an acute angle, or the like.
Next, with reference to
As illustrated in
The supply unit 25 includes the tank unit 26, which includes two reservoir portions 33 and 35 for storing liquid. The supply unit 25 may include a drive mechanism 27 configured to drive the tank unit 26.
The tank unit 26 is configured such that liquid supplied from the liquid container 24 flows into it and the liquid flows out of it toward the liquid ejecting head 23 configured to eject the liquid. The tank unit 26 includes a first inlet portion 60, a first reservoir portion 33, a second reservoir portion 35, and an outlet flow passage 34. The first reservoir portion 33 is in communication with the second reservoir portion 35 through the outlet flow passage 34. An on-off valve 36 is provided somewhere between the ends of the outlet flow passage 34. The first reservoir portion 33 is located upstream of the second reservoir portion 35 in the direction in which the liquid flows when supplied from the liquid container 24 toward the liquid ejecting head 23. The first reservoir portion 33 serves as a sub tank for temporarily retaining the liquid having flowed into the first reservoir portion 33 from the liquid container 24. The second reservoir portion 35 serves as a reservoir tank for temporarily retaining the liquid having flowed into the second reservoir portion 35 from the first reservoir portion 33 until the liquid is supplied to the liquid ejecting head 23.
The liquid having flowed in from the liquid container 24 that is in an attached state is stored in the first reservoir portion 33. When the liquid stored in the second reservoir portion 35 is consumed as a result of the supply of this liquid out of the second reservoir portion 35 to the liquid ejecting head 23, the on-off valve 36 opens, and replenishment liquid for making up for the consumption is supplied from the first reservoir portion 33 to the second reservoir portion 35 through the outlet flow passage 34. The on-off valve 36 may be a one-way valve. The on-off valve 36, a one-way valve, tolerates flow of the liquid from a first chamber 62 toward a second chamber 68 and does not tolerate flow of the liquid from the second chamber 68 toward the first chamber 62.
The first reservoir portion 33 includes the first chamber 62 (sub tank chamber) configured to store the liquid supplied from the liquid container 24. The second reservoir portion 35 includes the second chamber 68 (reservoir tank chamber) configured to store the liquid supplied from the first chamber 62 through the outlet flow passage 34 when the on-off valve 36 is open. The first chamber 62 is in communication with the second chamber 68 through the outlet flow passage 34. Though the above-mentioned on-off valve 36 provided on the outlet flow passage 34 may be controlled by the control portion 19, in the present embodiment, it is a differential pressure regulating valve capable of being opened and closed by a hydraulic head difference. A detailed structure of the on-off valve 36 will be explained later.
As illustrated in
The first opening-to-atmosphere portion 64 may be configured to be switchable between an open-to-atmosphere state, in which the inside of the first chamber 62 is open to atmosphere, and a non-open-to-atmosphere state, in which the inside of the first chamber 62 is not open to atmosphere. The second opening-to-atmosphere portion 69 may be configured to be switchable between an open-to-atmosphere state, in which the inside of the second chamber 68 is open to atmosphere, and a pressurized state, in which the inside of the second chamber 68 is at a pressure higher than atmospheric pressure.
The liquid ejecting apparatus 11 includes the liquid ejecting head 23, which is capable of ejecting liquid, and the supply flow passage 37 via which the tank unit 26 having the above structure is in communication with the liquid ejecting head 23. The liquid stored in the tank unit 26 is supplied to the liquid ejecting head 23 through the supply flow passage 37. The liquid ejecting head 23 ejects the liquid supplied from the tank unit 26 through the supply flow passage 37. The liquid ejecting apparatus 11 may further include a collection flow passage 39, through which the liquid ejecting head 23 is in communication with the tank unit 26. That is, the liquid ejecting apparatus 11 may include the supply flow passage 37, through which the liquid stored in the tank unit 26 is supplied to the liquid ejecting head 23, and the collection flow passage 39, through which the liquid is collected from the liquid ejecting head 23 to the tank unit 26. As described here, the liquid ejecting apparatus 11 may be configured to circulate the liquid between the tank unit 26 and the liquid ejecting head 23 through the supply flow passage 37 and the collection flow passage 39.
For example, liquid heated using a non-illustrated heater may be circulated between the tank unit 26 and the liquid ejecting head 23 so that the liquid ejecting apparatus 11 will be able to eject the liquid having a predetermined temperature from the liquid ejecting head 23. As another example, when the liquid is pigment-based ink, by circulating the liquid between the tank unit 26 and the liquid ejecting head 23, the liquid ejecting apparatus 11 may be configured to eject the liquid containing pigments dispersed uniformly therein from the liquid ejecting head 23, while suppressing the precipitation of the pigments in the liquid by utilizing stirring effects produced by the circulation of the liquid. Of course, the liquid may be circulated between the tank unit 26 and the liquid ejecting head 23 for any other purpose.
The liquid ejecting apparatus 11 may include the liquid ejecting head 23, the tank unit 26, the supply flow passage 37, a second inlet portion 75, and the collection flow passage 39. The tank unit 26 may include an outlet portion 74, via which the liquid contained inside flows out toward the liquid ejecting head 23 through the supply flow passage 37, and the second inlet portion 75, via which the liquid collected from the liquid ejecting head 23 through the collection flow passage 39 flows in. The supply flow passage 37 provides communication between the outlet portion 74 and the liquid ejecting head 23. The collection flow passage 39 provides communication between the liquid ejecting head 23 and the second inlet portion 75.
As illustrated in
The liquid ejecting head 23 has one or more nozzles 22 and a nozzle surface 21, in which these nozzles 22 are formed. The tank unit 26 is configured to supply the liquid contained in the liquid container 24 to the liquid ejecting head 23 through the first reservoir portion 33, the outlet flow passage 34, the second reservoir portion 35, and the supply flow passage 37. The liquid ejecting head 23 is configured to eject the supplied liquid from the nozzles 22.
The liquid ejecting apparatus 11, if equipped with a plurality of supply units 25 corresponding to different colors, is able to perform color printing by ejecting ink of the plurality of colors. A single drive mechanism 27 may drive a plurality of tank units 26 together. The liquid ejecting apparatus 11 may include a plurality of drive mechanisms 27 configured to drive a plurality of tank units 26 individually.
The liquid ejecting head 23 may be detachably attached to the body of the liquid ejecting apparatus 11. The liquid ejecting head 23 may be in a tilted position such that its nozzle surface 21 is inclined with respect to a horizontal plane. The liquid ejecting head 23 may, in a tilted position, perform printing by ejecting liquid toward the medium 12. The liquid ejecting head 23 may be a line-type head oriented in the direction of the width of the medium 12. The liquid ejecting head 23 may be a serial-type head configured to perform printing while moving in the direction of the width of the medium 12.
The liquid container 24 may have a containing chamber 29 that contains liquid. The liquid contained in the containing chamber 29 flows out via a pouring outlet portion 30. The pouring outlet portion 30 may include an outlet valve 31. The containing chamber 29 is, for example, a hermetically-closed space that is not in communication with atmosphere. The liquid container 24 before being attached to the attachment portion 28 may contain a larger amount of liquid than an amount of liquid that can be stored in the tank unit 26.
The supply unit 25 may include a supply valve 38, which can close the supply flow passage 37, the collection flow passage 39, a circulation valve 40, which can open and close the collection flow passage 39, and a liquid chamber 41. The liquid chamber 41 is located somewhere between the ends of the collection flow passage 39. The collection flow passage 39 has, as the ends, an upstream end connected to the liquid ejecting head 23 and a downstream end connected to the first reservoir portion 33. The collection flow passage 39 is a flow passage through which the liquid present inside the liquid ejecting head 23 flows toward the tank unit 26. The term “connected” as used herein shall be construed to encompass not only “directly connected”, “directly in (fluid) communication with” but also “indirectly connected”, “indirectly in (fluid) communication with”.
The liquid chamber 41 is located on the collection flow passage 39, specifically, between the liquid ejecting head 23 and the circulation valve 40. A part of the liquid chamber 41 is formed by a flexible member 42. Elastic deformation of the flexible member 42 causes a change in the capacity of the liquid chamber 41.
The liquid ejecting head 23 may include a first connection portion 44, to which the collection flow passage 39 is connected, and a second connection portion 45, to which the supply flow passage 37 is connected. The collection flow passage 39 has the upstream end connected to the first connection portion 44 and the downstream end connected to the first reservoir portion 33. The supply flow passage 37 has an upstream end connected to the second reservoir portion 35 and a downstream end connected to the second connection portion 45. The first connection portion 44 may be located at a position above the second connection portion 45 when the liquid ejecting head 23 is in a tilted position.
As illustrated in
The pressurizing portion 47 is, for example, a tube pump that includes rollers and a tube. In this case, the tube pump sends air by causing its rollers to rotate while squeezing the tube by the rollers. The non-illustrated tube of the pressurizing portion 471 has a first end connected to the air flow passage 55 and a second end connected to the connection flow passage 52. The pressurizing portion 47, when driven in a forward direction, sends air taken in from the air flow passage 55 into the connection flow passage 52. The pressurizing portion 47, when driven in a reverse direction, sends air taken in from the connection flow passage 52 into the air flow passage 55.
The supply unit 25 may include a pressurizing mechanism 57 configured to apply pressure to the liquid present inside the supply flow passage 37. The pressurizing mechanism 57 includes the pressurizing portion 47, the air chamber 53, and the air flow passage 55. The supply unit 25 may include a fine pressurizing portion 58 located on the collection flow passage 39 between the liquid ejecting head 23 and the circulation valve 40. The fine pressurizing portion 58 includes the pressurizing mechanism 57 and the liquid chamber 41. The fine pressurizing portion 58 is configured to apply pressure to the liquid present inside the collection flow passage 39. More particularly, the pressurizing mechanism 57 pressurizes the flexible member 42 from the outside of the liquid chamber 41.
Next, the first reservoir portion 33 will now be explained.
The first reservoir portion 33 may include the first inlet portion 60, the first chamber 62, a liquid surface detecting portion 63, and the first opening-to-atmosphere portion 64 The first inlet portion 60 may include an inlet valve 61.
When the liquid container 24 is attached to the attachment portion 28 (see
Liquid supplied from the liquid container 24 flows in via the first inlet portion 60. The first inlet portion 60 may be located over or above the first reservoir portion 33. For example, the first inlet portion 60 may be provided through the ceiling 65 of the first chamber 62. The lower end of the first inlet portion 60 may be located inside the first chamber 62 and may be located under or below the ceiling 65. The upper end of the first inlet portion 60 may be located outside the first chamber 62 and may be located over or above the ceiling 65. An example of a detailed structure of the first inlet portion 60 and the first chamber 62 will be explained later.
The first chamber 62 stores the liquid having flowed in via the first inlet portion 60. The lower end of the first inlet portion 60 is located below the nozzle surface 21. Therefore, the first liquid surface 66 of the liquid stored in the first chamber 62 changes in level within a range below the nozzle surface 21. Specifically, due to a hydraulic head difference from the liquid stored in the first reservoir portion 33, the liquid contained in the liquid container 24 flows via the pouring outlet portion 30 and the first inlet portion 60 into the first reservoir portion 33.
The first opening-to-atmosphere portion 64 is able to open the inside of the first chamber 62 to atmosphere. The first opening-to-atmosphere portion 64 is made of, for example, a vapor-liquid separator film. The term “vapor-liquid separator film” as used herein means a film member that has a function of not allowing liquid to pass through itself and allowing air to pass through itself The first opening-to-atmosphere portion 64 prevents the liquid stored in the first chamber 62 from leaking out and allows air to enter the first chamber 62 from the outside and to exit therefrom to the outside. Since the inside of the first chamber 62 is open to atmosphere as described above, the first liquid surface 66 changes in level due to a liquid inflow from the liquid container 24 via the first inlet portion 60 and due to a liquid outflow through the outlet flow passage 34.
One end of the outlet flow passage 34 is connected to the first chamber 62. The liquid stored in the first chamber 62 flows out through the outlet flow passage 34.
The on-off valve 36 is able to open and close the outlet flow passage 34. The on-off valve 36 may include a one-way valve that tolerates flow of the liquid from the first chamber 62 toward the second chamber 68 and does not tolerate flow of the liquid from the second chamber 68 toward the first chamber 62. A detailed structure of the on-off valve 36 will be explained later.
When the liquid contained in the liquid container 24 flows into the first reservoir portion 33 via the pouring outlet portion 30 and the first inlet portion 60, air flows from the first reservoir portion 33 into the liquid container 24 via the first inlet portion 60 and the pouring outlet portion 30, wherein an amount of the air corresponds to an amount of the liquid flowing into the first reservoir portion 33. In addition, the liquid-level position of the first liquid surface 66 rises by a level amount corresponding to the amount of the liquid flowing into the first reservoir portion 33. When the first liquid surface 66 rising in level reaches the lower end of the first inlet portion 60, the flow of the air from the first reservoir portion 33 into the liquid container 24 stops. Since the containing chamber 29 is hermetically closed, this stop of the flow of the air causes a decrease in the internal pressure of the containing chamber 29 corresponding to an amount of the liquid flowing in. Then, the flow of the liquid from the liquid container 24 into the first reservoir portion 33 stops when the negative pressure inside the containing chamber 29 becomes greater than the hydraulic head of the liquid contained in the containing chamber 29.
When liquid flows from the first reservoir portion 33 to the second reservoir portion 35, the liquid-level position of the first liquid surface 66 drops. When the first liquid surface 66 dropping in level falls below the lower end of the first inlet portion 60, air flows into the containing chamber 29 via the first inlet portion 60 and the pouring outlet portion 30, and the negative pressure inside the containing chamber 29 decreases. Then, the liquid contained in the liquid container 24 flows into the first reservoir portion 33 when the negative pressure inside the containing chamber 29 becomes less than the hydraulic head of the liquid contained in the containing chamber 29. As a result, the first liquid surface 66 is kept at a standard level position SH that is a position near the lower end of the first inlet portion 60 while the liquid is present inside the liquid container 24. The first liquid surface 66 is at a level below the standard level position SH when the liquid container 24 is running out of the liquid.
The tank unit 26 further includes the liquid surface detecting portion 63 configured to detect the surface level of the liquid stored in the first chamber 62. The liquid surface detecting portion 63 may detect that the first liquid surface 66 is at the standard level position SH. The liquid surface detecting portion 63 may detect that the first liquid surface 66 is at a level below the standard level position SH. The liquid surface detecting portion 63 may detect that the first liquid surface 66 is at a full level position. The full level position is above the standard level position SH. The maximum amount of liquid is stored in the first reservoir portion 33 when the first liquid surface 66 is at the full level position. The control portion 19 may determine the liquid container 24 as being empty when the liquid surface detecting portion 63 detects that the first liquid surface 66 is at a level below the standard level position SH, and then may prompt the user to replace this liquid container 24 with another one.
The standard level position SH is set to be, for example, a position above the downstream end of the collection flow passage 39 in the first chamber 62. If set so, when the first liquid surface 66 is at the standard level position SH, the liquid stored in the first reservoir portion 33 is able to flow into the liquid ejecting head 23 through the collection flow passage 39.
Next, the second reservoir portion 35 will now be explained.
The second chamber 68 is connected to the other end of the outlet flow passage 34. The second chamber 68 stores the liquid supplied from the first chamber 62. The second reservoir portion 35 may include the second chamber 68 and the second opening-to-atmosphere portion 69, by which the second chamber 68 is partitioned off from the pressurizing flow passage 51.
The second opening-to-atmosphere portion 69 is able to open the inside of the second chamber 68 to atmosphere. The second opening-to-atmosphere portion 69 is made of, for example, a vapor-liquid separator film. This vapor-liquid separator film is a film member that has a function of allowing air to pass through itself and not allowing liquid to pass through itself, similarly to the vapor-liquid separator film of the first opening-to-atmosphere portion 64.
The liquid stored in the first reservoir portion 33 flows into the second chamber 68 due to a hydraulic head difference from the liquid stored in the second reservoir portion 35. When the internal pressure of the first chamber 62 and the internal pressure of the second chamber 68 are atmospheric pressure, the second liquid surface 70 of the liquid stored in the second reservoir portion 35 is the same in level as the first liquid surface 66. In other words, the second liquid surface 70 is kept at the standard level position SH, which is almost the same as the level of the lower end of the first inlet portion 60, and changes in level within a range below the nozzle surface 21. The liquid present inside the liquid ejecting head 23 is kept to be in negative pressure due to a hydraulic head difference between the liquid stored in the first reservoir portion 33 and the liquid stored in the second reservoir portion 35. When the liquid ejecting head 23 consumes the liquid, the liquid stored in the second reservoir portion 35 is supplied to the liquid ejecting head 23.
When the on-off valve 36 includes a one-way valve, the one-way valve closes the outlet flow passage 34 when the internal pressure of the second reservoir portion 35 is higher than the internal pressure of the first reservoir portion 33. Therefore, the one-way valve closes the outlet flow passage 34 when the pressurizing portion 47 applies pressure to the inside of the second reservoir portion 35.
The control portion 19 (see
Next, the switching mechanism 48 will now be explained.
The switching mechanism 48 includes a thin tube portion 72, which is a part of the connection flow passage 52, and first to eleventh selection valves 73a to 73k. The thin tube portion 72 is a meandering tube that is thin enough to the extent that the flow of liquid is significantly restricted in relation to the flow of air.
The air flow passage 55 comes into communication with atmosphere when the first selection valve 73a opens. The air flow passage 55 comes into communication with the pressure sensor 49 when the second selection valve 73b opens. When the third selection valve 73c opens, the air flow passage 55 opens, and the pressurizing portion 47 comes into communication with the air chamber 53.
The connection flow passage 52 between the pressurizing portion 47 and the eighth selection valve 73h comes into communication with atmosphere when the fourth selection valve 73d opens. The connection flow passage 52 comes into communication with the pressure sensor 49 when the fifth selection valve 73e opens. The connection flow passage 52 comes into communication with atmosphere when the sixth selection valve 73f and the seventh selection valve 73g open. The connection flow passage 52 opens when the eighth selection valve 73h opens. The thin tube portion 72 comes into communication with atmosphere when the ninth selection valve 73i opens. When the tenth selection valve 73j opens, the opening-to-atmosphere path 50 opens, and the first reservoir portion 33 comes into communication with the connection flow passage 52. When the eleventh selection valve 73k opens, the pressurizing flow passage 51 opens, and the second reservoir portion 35 comes into communication with the connection flow passage 52.
To change the internal pressure of the air chamber 53, the switching mechanism 48 opens the second to fourth selection valves 73b to 73d and closes the other selection valves. When the pressurizing portion 47 is driven in the forward direction in this state, air that is present inside the air chamber 53 exits through the air flow passage 55 and the connection flow passage 52 and, therefore, the internal pressure of the air chamber 53 decreases. When the pressurizing portion 47 is driven in the reverse direction in this state, air is taken into the air chamber 53 through the connection flow passage 52 and the air flow passage 55 and, therefore, the internal pressure of the air chamber 53 increases. The pressure sensor 49 may detect the internal pressure of the air flow passage 55 and the air chamber 53 at this time. The control portion 19 (see
To open the first reservoir portion 33 to atmosphere, the switching mechanism 48 opens the sixth selection valve 73f and the tenth selection valve 73j. The first chamber 62 comes into communication with atmosphere through the opening-to-atmosphere path 50 and the connection flow passage 52.
To open the second reservoir portion 35 to atmosphere, the switching mechanism 48 opens the seventh selection valve 73g and the eleventh selection valve 73k. The second chamber 68 comes into communication with atmosphere through the pressurizing flow passage 51 and the connection flow passage 52.
To apply pressure to the inside of the second reservoir portion 35, the switching mechanism 48 opens the first selection valve 73a, the fifth selection valve 73e, the eighth selection valve 73h, and the eleventh selection valve 73k, and closes the other selection valves. When the pressurizing portion 47 is driven in the forward direction in this state, air flows into the second chamber 68 through the air flow passage 55, the connection flow passage 52, and the pressurizing flow passage 51 and, therefore, the internal pressure of the second chamber 68 increases. The pressure sensor 49 may detect the internal pressure of the connection flow passage 52, the pressurizing flow passage 51, and the second chamber 68 at this time. The control portion 19 may control the driving of the pressurizing portion 47 based on the detection result of the pressure sensor 49.
Next, with reference to
As illustrated in
As illustrated in
The liquid container 24 may have a positioning hole 448 in the bottom wall 144. The positioning hole 448 may be a recess formed in the bottom wall 144. The liquid container 24 may have the pouring outlet portion 30 having its opening in the bottom wall 144. The liquid contained in the liquid container 24 flows out of the liquid container 24 via the pouring outlet portion 30. The liquid container 24 may have a release portion 241 protruding down from the bottom wall 144. The release portion 241, the positioning hole 448, the pouring outlet portion 30 may be arranged in this order as viewed from the second end wall 147 toward the first end wall 142.
As illustrated in
The liquid container 24 may have two guided portions 447 extending along the Y axis in the first sidewall 145 and the second sidewall 146 respectively. In each of the sidewalls 145 and 146, the guided portion 447 may include a first guided portion 447a and a second guided portion 447b formed at different positions in height. The first guided portion 447a may be a groove extending along the bottom wall 144. The second guided portion 447b is located above the first guided portion 447a. The second guided portion 447b is shorter than the first guided portion 447a in the direction along the Y axis. The second guided portion 447b may be located near the circuit board chip 150.
As illustrated in
As illustrated in
The supporting member 90 extends along a linear guiding path 82 (indicated by an open arrow in
The pivot 91 is disposed at the base-end region of the supporting member 90. The pivot 91 has its axial line intersecting with both of the vertical line (Z axis) and the guiding path 82 (Y axis). The axial line of the pivot 91 extends along the X axis. The supporting member 90 is configured to rotate on the pivot 91 between a guiding position, which is a position for guiding the liquid container 24 along the guiding path 82 (indicated by alternate long and short dash lines in
The first inlet portion 60 is disposed below the supporting member 90. The first inlet portion 60 becomes connected to the liquid container 24 when the supporting member 90 comes to the connection position. The first inlet portion 60 may be in a tilted position with respect to the guiding path 82 (which is horizontal). More specifically, the first inlet portion 60 may be tilted such that its head end (upper end) is located closer to the insertion opening 28o than its base end (lower end) is. For example, the axial line of the first inlet portion 60 may be inclined with respect to the vertical line (Z axis) within an angular range of 0° to 15°.
The liquid container 24 may include one or more guiding portions 247 configured to guide the movement of the liquid container 24. For example, the guiding portions 247 may be a pair of guide rails provided on the side ribs 90b making up a pair. Alternatively, a single guide rail may be provided on the bottom plate 90a.
The guiding portion 247 may include a first guiding portion 247a and a second guiding portion 247b disposed such that the first guided portion 447a and the second guided portion 447b are configured to come into engagement therewith respectively. The guiding portion 247a, 247b may be, for example, a protruding portion extending in the length direction of the supporting member 90. The second guiding portion 247b is located above the first guiding portion 247a. The second guiding portion 247b is shorter than the first guiding portion 247a in the length direction. The second guiding portion 247b may be located closer to the pivot 91 than the first guiding portion 247a is. The first guiding portion 247a may be disposed at a position corresponding to the first inlet portion 60 in the direction of the movement of the liquid container 24.
The attachment portion 28 may include a first urging member 83 configured to urge the supporting member 90 from the connection position toward the guiding position. The first urging member 83 is, for example, a coil spring. In an initial state in which there is no liquid container 24 in the attachment portion 28, the supporting member 90 is located at the guiding position by being urged by the first urging member 83.
As illustrated in
As illustrated in
The latching lever 84 is disposed in such a way as to latch onto the liquid container 24 supported by the supporting member 90 when the supporting member 90 is located at the connection position. The latching lever 84 may have a first sloped surface 86 extending obliquely downward from the head end and a second sloped surface 87 extending obliquely downward from the lower end of the first sloped surface 86. The first sloped surface 86 and the second sloped surface 87 form a protrusion protruding toward the supporting member 90.
The first sloped surface 86 engages with the liquid container 24 when the supporting member 90 rotates along a rotation path from the guiding position (position illustrated in
Next, with reference to
As illustrated in
As illustrated in
As illustrated in
Next, operation performed when the liquid container 24 is attached to the supply unit 25 will now be explained.
As illustrated in
When the liquid container 24 comes to a position near the termination end of the guiding path 82, the second guided portions 447b come into engagement with the second guiding portions 247b. An electric coupling portion (not illustrated) may be disposed between the first guiding portions 247a and the second guiding portions 247b in the vertical direction Z. In this case, the connection terminals 521 are positioned appropriately toward the electric coupling portion in the vertical direction Z. The liquid container 24 may be positioned in the width direction by an identification shape portion disposed near the electric coupling portion.
The connection terminals 521 are coupled to the electric coupling portion when the liquid container 24 arrives at the termination end of the guiding path 82. This makes it possible to perform data communication between the circuit board chip 150 and the control portion 19 (see
Next, the user pushes the rear end (the right end in
Due to expansion and contraction of an urging spring (not illustrated), a small change in position of the liquid container 24 along the Y axis is allowed while keeping the coupling of the connection terminals 521 to the electric coupling portion (not illustrated). The positioning protruding portion 248 is disposed near the first inlet portion 60, and the positioning protruding portion 248 is inclined at the same angle as that of the first inlet portion 60; therefore, the pouring outlet portion 30 is guided toward the first inlet portion 60 properly.
In the process of rotation of the supporting member 90 to the connection position, the liquid container 24 supported by the supporting member 90 comes into contact with the first sloped surface 86 of the latching lever 84. The upper end of the latching lever 84 pushed by the liquid container 24 changes its position outward (rightward in
As illustrated in
Next, operation performed when the liquid container 24 is detached from the supply unit 25 will now be explained.
To detach the liquid container 24 from the attachment portion 28, the user pulls the rear end (the right end in
In the process of rotation of the supporting member 90 from the connection position to the guiding position, the pouring outlet portion 30 becomes disconnected from the first inlet portion 60, and the positioning protruding portion 248 gets out of the positioning hole 448. In the process of disconnection of the pouring outlet portion 30 from the first inlet portion 60, both of the outlet valve 31 and the inlet valve 61 become closed. Upon the arrival of the supporting member 90 at the guiding position, the liquid container 24 is pushed toward the start end of the guiding path 82 due to the urging force applied by the fourth urging member (not illustrated). Since the liquid container 24 is guided by the first guiding portions 247a and the second guiding portions 247b, the connection terminals 521 are uncoupled from the electric coupling portion (not illustrated) of the attachment portion 28 quickly without being twisted. At the same time, the release portion 241 is released from a first arm (not illustrated), and the lock lever 92 returns to a lock position due to an urging force applied by the third urging member (not illustrated).
The user thereafter draws the liquid container 24 toward the outside of the frame 80. The liquid container 24 that is being drawn outward is guided by the first guiding portions 247a. Since the rotation of the supporting member 90 is restricted by the lock lever 92, the liquid container 24 moves horizontally along the Y axis without any contact with the first inlet portion 60.
Next, with reference to
As illustrated in
The first inlet portion 60 is configured to be connected to the liquid container 24 (see
As illustrated in
The first inlet portion 60 may have a regulating portion 602 for partitioning off the inlet passage 601 from the first chamber 62. The regulating portion 602 serves as a partition plate between the inlet passage 601 and the first chamber 62. The regulating portion 602 has a function of regulating, to the standard level position SH, the first liquid surface 66 indicating the level of the liquid stored in the first chamber 62.
As illustrated in
The second inlet portion 75 is in communication with the first chamber 62. The liquid collected from the liquid ejecting head 23 is configured to flow in via the second inlet portion 75. The second inlet portion 75 is in communication with one end of the collection flow passage 39, which is in communication with the liquid ejecting head 23.
As illustrated in
The first chamber 62 of the tank unit 26 is in communication with the opening-to-atmosphere path 50 (see
As illustrated in
The second air flow passage 79 is in communication with the second chamber 68 via the second opening-to-atmosphere portion 69. The second chamber 68 is in communication with the pressurizing flow passage 51 (see
When the time for cleaning has come, the control portion 19 drives the pressurizing portion 47 to supply pressurized air therefrom into the second chamber 68, thereby applying pressure to the liquid stored in the second chamber 68. As a result, the liquid is forced out through the nozzles 22 of the liquid ejecting head 23. The cleaning of the liquid ejecting head 23 is performed in this way. The cleaning prevents the nozzles 22 of the liquid ejecting head 23 from becoming clogged or unclogs the clogged nozzles, etc.
When the second opening-to-atmosphere portion 69 includes a vapor-liquid separator film, it is possible to supply pressurized air into the second chamber 68 while preventing the liquid stored in the second chamber 68 from leaking out. Pressurized air may be supplied from the pressurizing portion 47 into the first chamber 62 through the opening-to-atmosphere path 50.
As illustrated in
A lower end 604 of the regulating portion 602 regulates the liquid-level position of the first liquid surface 66 to the standard level position SH. That is, the position of the lower end 604 of the regulating portion 602 is set such that the first liquid surface 66 will be at the standard level position SH. The first liquid surface 66 rises in level when the liquid flows in from the liquid container 24. Then, the first liquid surface 66 rising in level reaches the lower end 604 of the regulating portion 602. Upon the reaching thereof, the supply of the liquid from the liquid container 24 via the first inlet portion 60 stops.
The inside of the first chamber 62 is divided into a first liquid-phase portion 62L, which is a liquid-phase portion where liquid is stored, and the first vapor-phase portion 62G, which is a vapor-phase portion where air is present, with the first liquid surface 66 being the boundary therebetween. That is, the first chamber 62 is divided into the first liquid-phase portion 62L, which is a region located below the first liquid surface 66, and the first vapor-phase portion 62G, which is a region located above the first liquid surface 66.
The inside of the second chamber 68 is divided into a second liquid-phase portion 68L, which is a liquid-phase portion where liquid is stored, and a second vapor-phase portion 68G, which is a vapor-phase portion where air is present, with the second liquid surface 70 being the boundary therebetween. That is, the second chamber 68 is divided into the second liquid-phase portion 68L, which is a region located below the second liquid surface 70, and the second vapor-phase portion 68G, which is a region located above the second liquid surface 70. The upper portion of a region including the inside of the inlet passage 601 is formed as an inlet vapor-phase portion 60G, which is a vapor-phase portion where air is present, with a liquid surface 67 being the boundary therebetween. The liquid-level position of the liquid surface 67 is almost the same as that of the first liquid surface 66.
As illustrated in
The second detecting portion 63b illustrated in
The third detecting portion 63c illustrated in
As illustrated in
The first chamber 62 is the detection-target reservoir chamber configured such that the amount of liquid left in the tank unit 26 is detected by the liquid surface detecting portion 63. For the purpose of reducing variation in END detection precision when the amount of the liquid left in the first chamber 62 has reached “END”, it is preferable if the percentage of change in liquid level per unit amount of liquid is large when the amount of the liquid left in the first chamber 62 has become small. Therefore, it is preferable if the first chamber 62 has a shape the capacity of the lower portion of which is smaller than the capacity of the upper portion thereof. On the other hand, for the purpose of enabling the first chamber 62 to accommodate liquid forced out by thermal expansion at the vapor-phase portion inside the liquid container 24 due to a change in temperature, it is preferable if the first chamber 62 has a large capacity. For these reasons, preferably, the first chamber 62 should have a shape that has a large capacity at its upper portion though the capacity of its lower portion is small, as illustrated in
Since there is no need to detect the second liquid surface 70, the second chamber 68 can be configured to have a shape that has a larger capacity at its lower portion than its upper portion as illustrated in
As illustrated in
As illustrated in
As illustrated in
As illustrated in
As illustrated in
As illustrated in
As illustrated in
As illustrated in
As illustrated in
Based on the detection signal supplied from the tilt detecting portion 98, the control portion 19 determines whether the angle of the tilt of the tank unit 26 exceeds an angular threshold or not. When the angle of the tilt of the tank unit 26 exceeds the angular threshold, the control portion 19 prohibits the liquid ejecting apparatus 11 from performing print operation (liquid ejecting operation). In addition, the control portion 19 causes the display portion 15a to display a message, etc. that prompts the user to adjust the tilt of the liquid ejecting apparatus 11. One of the causes of excessive inflow of the liquid from the liquid container 24 into the first reservoir portion 33 is a tilt exceeding the tolerance of the tank unit 26. Therefore, the control portion 19 may cause the display portion 15a to display a message, etc. that prompts the user to adjust the tilt of the liquid ejecting apparatus 11 when the angle of the tilt of the tank unit 26 detected by the tilt detecting portion 98 exceeds a predetermined angular threshold. When the angle of the tilt of the tank unit 26 detected by the tilt detecting portion 98 exceeds a predetermined angular threshold, the control portion 19 may put the liquid ejecting apparatus 11 into a state in which printing cannot be started until the excessive tilt is corrected. In this case, print operation of the liquid ejecting apparatus 11 based on a print instruction given by the user is started when the angle of the tilt detected by the tilt detecting portion 98 becomes less than the angular threshold as a result of the corrective adjustment of the tilt of the liquid ejecting apparatus 11 by the user.
As illustrated in
The tank unit 26 includes absorption members 93 and 94 disposed under the first reservoir portion 33. The absorption member 93, 94 has a function of absorbing the liquid such as ink that leaks during the attachment and detachment of the liquid container 24. The absorption members 93 and 94 are disposed throughout an area where they are able to absorb the liquid having spattered from or having trickled down the first inlet portion 60. The liquid spattering from the first inlet portion 60 or the liquid running down along the side surface of the first inlet portion 60 are guided to the first absorption member 93.
The first absorption member 93 is supported on the frame 89 in upright position along the vertical direction Z near a position that is right under the first inlet portion 60. The second absorption member 94 is provided horizontally on the frame 89 in a state in which a part of the second absorption member 94 is in contact with the base end portion of the first absorption member 93. As illustrated in
Next, with reference to
As illustrated in
First, with reference to
The first inlet portion 60 has the liquid spattering prevention wall 605, which is mounted on the head end portion on the inlet (60a) side to cover its periphery, with the inlet 60a only being opened. The liquid spattering prevention wall 605 has an annular wall portion covering the periphery of the inlet 60a.
As illustrated in
For this reason, the tank unit 26 has a liquid collection structure for collecting the liquid that has spattered from the inlet 60a. The liquid collection structure includes the annular guiding groove 606 illustrated in
The liquid collection structure includes the guiding groove 606 at an area where it can catch the liquid having spattered from the inlet 60a and having dropped around the inlet 60a. The first inlet portion 60 has a columnar protruding portion 607 having the inlet 60a at its mouse. The guiding groove 606 is formed as an annular grooved path in the upper surface of a truncated-cone portion disposed at the base of the protruding portion 607.
In a side view from the direction along the X axis in
As illustrated in
As illustrated in
Next, with reference to
For example, an umbrella valve, which is an umbrella-type valve body, has been sometimes used in related art as the valve body of this kind of differential pressure regulating valve configured to be opened and closed by a hydraulic head difference. However, if an umbrella valve is used, there is a possibility that minute leakage of liquid might occur because it is difficult to ensure required close contact pressure with a valve seat. Minute leakage of this kind could cause variation in the level of the second liquid surface 70. This means variation in a hydraulic head difference, and has an influence on the size of a liquid droplet ejected from the liquid ejecting head 23, resulting in affecting print quality. Therefore, it is demanded that an amount of minute leakage of this kind should be as small as possible, or, ideally, zero. In view of this, in the present embodiment, the valve body 101 that has a shape illustrated in
As illustrated in
The valve portion 103 includes a valve plate portion 103a, which has a shape like a disc with enhanced rigidity achieved by securing a predetermined thickness, a rip portion 105, which is an annular continuous seal protruding from the shaft-portion-side (102) surface of the valve plate portion 103a, and an annular flange portion 106, which extends outward in the radial direction from the periphery of the valve plate portion 103a. The flange portion 106 is thinner than, and is more flexible than, the valve plate portion 103a. The thickness of the flange portion 106 may decrease as it goes toward the outer rim.
As illustrated in
The valve portion of an umbrella valve according to related art has such a shape that, for example, the thickness of the entire valve body decreases gradually as it goes toward the outer rim in the radial direction. Therefore, the valve portion of an umbrella valve according to related art has a comparatively wide flexible potion. For this reason, the valve portion of an umbrella valve according to related art deforms easily due to its high flexibility and, therefore, a pressurizing force applied when the valve portion is in contact with the valve seat is relatively weak. Because of its relatively weak pressuring force, an umbrella valve according to related art has a structure that is prone to minute leakage at a valve-closing position.
By contrast, the valve body 101 according to the present embodiment has a shape like a disc with an almost constant thickness and a comparatively high rigidity. Moreover, the valve body 101 according to the present embodiment has the rip portion 105, which is a continuous seal protruding in an annular shape on the surface, of the valve plate portion 103a, facing the valve seat 333. The valve portion 103 has the annular flange portion 106, which extends outward in the radial direction from the periphery of the valve plate portion 103a. As described here, the valve body 101 includes the annular rip portion 105 and the annular flange portion 106 located on the outer-rim side to surround the rip portion 105. When the on-off valve 36 is closed, continuous sealing is provided by the press contact of the rip portion 105 with the valve seat 333, and the flange portion 106 is pressed in a slightly deformed state against the surface of the valve seat 333 outside the continuous seal. Therefore, a necessary pressurizing force can be obtained when the valve body 101 is in contact with the valve seat 333 due to the closing of the on-off valve 36.
Moreover, since the on-off valve 36 has the plurality of valve holes 332 whose cross-sectional flow-passage area size is comparatively small as illustrated in FIG. 17, pressure loss is great due to comparatively large flow resistance at the time of opening. Therefore, in order to reduce pressure loss, two on-off valves 36 may be provided side by side as in the example illustrated in
The on-off valve 36 is a differential pressure regulating valve that includes a float-type valve body 101 that opens and closes by a hydraulic head difference in the level of the liquid surface between the first chamber 62 and the second chamber 68. The term “float-type valve body” as used herein means a differential pressure regulating valve body that opens and closes by movement of the valve body 101 that is in a state of floating in the liquid because of a difference in liquid pressure due to a hydraulic head difference between the first chamber 62 and the second chamber 68, without using any urging member such as a spring that urges the valve body 101 in a valve-closing direction. Since the on-off valve 36 is a float-type valve that can be opened by a small hydraulic head difference, it opens immediately when there is even a slight difference in liquid level between the first liquid surface 66 and the second liquid surface 70. Therefore, it is possible to adjust the second liquid surface 70 into the same level as the first liquid surface 66, and a difference in liquid level between the first liquid surface 66 and the second liquid surface 70 does not occur easily.
Next, with reference to
As illustrated in
Next, with reference to
As illustrated in
However, despite this design, it could happen that the user attempts to push the liquid container 24 inward by force. In this case, if the user attempts to push the liquid container 24 inward while tilting the liquid container 24, as illustrated in
To avoid such a deadlock state, as illustrated in
Next, operation of the present embodiment will now be explained.
The user attaches the liquid container 24 to the attachment portion 28 of the tank unit 26. Due to this attachment, the pouring outlet portion 30 of the liquid container 24 becomes connected to the first inlet portion 60 of the tank unit 26. Such attachment of the liquid container 24 is performed when, for example, the liquid container 24 having run out of the liquid is replaced with another one 24, for example, when the liquid in the tank unit 26 is detected as END, or when a state in which the first liquid surface 66 in the first chamber 62 is below the standard level position SH continues for longer than a predetermined period. In this case, the control portion 19 causes the display portion 15a to display a message, etc. that prompts the user to replace the liquid container 24 with another one. Prompted by the message, the user replaces this liquid container 24 with another one.
The first inlet portion 60 is in communication with the first chamber 62 via the opening portion 603, which is located at some midpoint in the vertical direction Z of the first chamber 62. Liquid is supplied from the liquid container 24 into the first chamber 62 while the first vapor-phase portion 62G and the inlet vapor-phase portion 60G are in communication with each other via the opening portion 603. Then, the first vapor-phase portion 62G and the inlet vapor-phase portion 60G become not in communication with each other when the first liquid surface 66 in the first chamber 62 reaches the standard level position SH (see
When the liquid is supplied from the second chamber 68 to the liquid ejecting head 23, and the second liquid surface 70 therefore becomes lower in level than the first liquid surface 66, the on-off valve 36 opens due to a hydraulic head difference between the first chamber 62 and the second chamber 68. As a result, the liquid flows from the first chamber 62 to the second chamber 68 through the outlet flow passage 34. When the liquid-level position of the first liquid surface 66 drops below the standard level position SH due to this flow, the first vapor-phase portion 62G and the inlet vapor-phase portion 60G come back into communication with each other to form an air flow passage again, and the supply of the liquid from the liquid container 24 to the first chamber 62 starts.
The first liquid surface 66 rises in level due to the supply of the liquid from the liquid container 24 to the first chamber 62, and the first liquid surface 66 becomes higher in level than the second liquid surface 70. When the liquid stored in the second chamber 68 is supplied to the liquid ejecting head 23 for liquid circulation, printing (liquid ejecting processing), and cleaning, the second liquid surface 70 drops in level, and the second liquid surface 70 becomes lower in level than the first liquid surface 66.
In these cases, the level of the first liquid surface 66 and the level of the second liquid surface 70 are adjusted to become equal to each other by the opening of the on-off valve 36. The on-off valve 36 closes when there is no longer a hydraulic head difference because the level of the first liquid surface 66 and the level of the second liquid surface 70 have become almost equal to each other. As described here, the liquid-level position of the first liquid surface 66 and the liquid-level position of the second liquid surface 70 are adjusted to the standard level position SH, meaning almost the same level (see
In this way, the first liquid surface 66 in the first chamber 62 is autonomously adjusted to the standard level position SH, which is a position where the first inlet portion 60 is connected to the first chamber 62 via the opening portion 603 at the lower end of the inlet passage 601, and which is at some midpoint in the vertical direction Z of the first chamber 62. That is, the first liquid surface 66 is autonomously adjusted to the standard level position SH, which is at the level of the lower end 604 of the regulating portion 602 serving as a partition between the inlet passage 601 and the first chamber 62.
As illustrated in
For example, when the first liquid surface 66 rises in level beyond the full level position due to inclination of the liquid ejecting apparatus 11 or for any other reason, there is a risk that the leakage of the liquid through the nozzles 22 of the liquid ejecting head 23 might occur due to a hydraulic head difference. However, in the present embodiment, when it is detected by the liquid surface detecting portion 63 that the liquid surface is at the full level position, or when the tilt of the tank unit 26 exceeding the angular threshold is detected by the tilt detecting portion 98, the control portion 19 prohibits the liquid ejecting apparatus 11 from starting printing. Then, the control portion 19 causes the display portion 15a to display a message that prompts the user to eliminate the tilt of the liquid ejecting apparatus 11. Prompted by the message, the user eliminates the tilt of the liquid ejecting apparatus 11. When the detection result of the tilt detecting portion 98 becomes less than the angular threshold as a result of the tilt elimination, the control portion 19 causes printing to be started.
The liquid ejecting apparatus 11 causes the liquid to circulate when in a standby state, in which printing is not performed. The liquid circulates by flowing through the second chamber 68 of the tank unit 26, the supply flow passage 37, the liquid ejecting head 23, and the collection flow passage 39 and then returning to the first chamber 62 of the tank unit 26. The supply valve 38 and the circulation valve 40 are open at this time. The second chamber 68 is pressurized in a state in which the first chamber 62 is opened to atmosphere via the first opening-to-atmosphere portion 64.
As illustrated in
When this liquid circulation is performed, the liquid returning from the liquid ejecting head 23 to the first chamber 62 of the tank unit 26 flows into the first chamber 62 via the communication opening 75a. It could happen that the liquid gushes out into the first chamber 62 from the communication opening 75a at this time. However, in the present embodiment, the eave-like cover portion 88 is provided at a position where it faces the communication opening 75a inside the first chamber 62. Therefore, the liquid gushing out with great energy from the communication opening 75a hits against the cover portion 88, and its energy is therefore abated. Consequently, it is possible to reduce the possibility that the liquid gushing out from the communication opening 75a reaches an area where the liquid is not supposed to flow in, for example, the opening-to-atmosphere port 33a.
The liquid that circulates flows through the filter 100 in the process of being supplied from the second chamber 68 toward the liquid ejecting head 23. The filter 100 traps foreign objects such as air bubbles or fine dust particles contained in the liquid that circulates. Therefore, when the liquid ejecting apparatus 11 performs printing, the liquid after the removal of the foreign objects such as air bubbles are supplied to the liquid ejecting head 23.
At least one of the supply valve 38 or the circulation valve 40 is opened during printing. The number of valves that are opened, of the supply valve 38 and the circulation valve 40, may be determined depending on an amount of liquid ejected from the nozzles 22 of the liquid ejecting head 23. For example, based on print data, when an ejection amount is not greater than a predetermined value, the control portion 19 may cause the supply valve 38 only to be opened. For example, based on print data, when an ejection amount is greater than a predetermined value, the control portion 19 may cause both the supply valve 38 and the circulation valve 40 to be opened.
When printing is performed, the switching mechanism 48 opens the sixth selection valve 73f and the tenth selection valve 73j to communicate the inside of the first chamber 62 with atmosphere through the opening-to-atmosphere path 50 and the connection flow passage 52. In addition, the switching mechanism 48 opens the seventh selection valve 73g and the eleventh selection valve 73k to communicate the inside of the second chamber 68 with atmosphere through the pressurizing flow passage 51 and the connection flow passage 52.
When printing is performed, based on a hydraulic head difference between the second liquid surface 70 inside the second chamber 68 and the nozzles 22, and based on a hydraulic head difference between the first liquid surface 66 inside the first chamber 62 and the nozzles 22, negative pressure acts on the liquid present inside the liquid ejecting head 23. When printing is performed, the liquid stored in the second chamber 68 is supplied to the liquid ejecting head 23 through the supply flow passage 37, and the liquid stored in the first chamber 62 is supplied to the liquid ejecting head 23 through the collection flow passage 39 in an OUT direction indicated by the broken-line arrow in
The liquid ejecting apparatus 11 performs pressurization cleaning of the liquid ejecting head 23 periodically or non-periodically. In pressurization cleaning, pressure is applied to the liquid stored in the second chamber 68 to pressurize the liquid present inside the liquid ejecting head 23, thereby forcibly ejecting the liquid from the nozzles 22. In this process, the second chamber 68 is pressurized in a state in which the supply valve 38 is open and the circulation valve 40 is closed. By the driving of the pressurizing portion 47 in the forward direction, air having flowed through the connection flow passage 52 and the pressurizing flow passage 51 enters the second chamber 68 via the opening-to-atmosphere portion 69. As a result, the inside of the second chamber 68 is pressurized.
The liquid present inside the liquid ejecting head 23 is pressurized due to the pressurization of the liquid stored in the second chamber 68 in a state in which the circulation valve 40 is open. Pressurization cleaning for forcibly ejecting the liquid from the nozzles 22 of the liquid ejecting head 23 is performed in this way. The on-off valve 36 is closed due to the pressurization force of the second chamber 68 at this time. The liquid is ejected from the nozzles 22 by this pressurization cleaning into a non-illustrated cap or a non-illustrated flushing box. The liquid is collected from the cap or the flushing box to a non-illustrated waste liquid collection portion.
Effects of the present embodiment will now be explained.
(1) The tank unit 26 is configured such that liquid supplied from the liquid container 24 flows into it and the liquid flows out of it toward the liquid ejecting head 23 configured to eject the liquid. The tank unit 26 includes the first inlet portion 60 via which the liquid supplied from the liquid container 24 flows in; the first chamber 62 configured to store the liquid that flows in via the first inlet portion 60; and the first opening-to-atmosphere portion 64 configured to open an inside of the first chamber 62 to atmosphere. The tank unit 26 further includes the outlet flow passage 34 to which one end is connected to the first chamber 62 and through which the liquid stored in the first chamber 62 flows out; the second chamber 68 connected to the other end of the outlet flow passage 34 and configured to store the liquid supplied from the first chamber 62; and the second opening-to-atmosphere portion 69 configured to open an inside of the second chamber 68 to atmosphere. The tank unit 26 further includes the on-off valve 36 configured to open and close the outlet flow passage 34. The first inlet portion 60 is connected to the first chamber 62 via the opening portion 603 at some midpoint in the vertical direction Z of the first chamber 62. With this structure, it is possible to adjust the liquid surface of the two reservoir chambers 62 and 68 into an appropriate level without any need for performing supply control, etc.
(2) In the tank unit 26, the opening portion 603 is located below the center inside the first chamber 62 in the vertical direction Z. With this structure, when there is liquid movement between the first chamber 62, the second chamber 68, and the liquid container 24 due to an ambient change, etc., it is possible to prevent an overflow of the liquid from the reservoir chamber, etc.
(3) The tank unit 26 further includes the liquid surface detecting portion 63 configured to detect the surface level of the liquid stored in the first chamber 62. With this structure, it is possible to detect that the liquid left in the liquid container 24 has become small, and it is possible to prevent the overflow of the liquid stored in the first chamber 62.
(4) In the tank unit 26, the on-off valve 36 includes a one-way valve that tolerates flow of the liquid from the first chamber 62 toward the second chamber 68 and does not tolerate flow of the liquid from the second chamber 68 toward the first chamber 62. This structure makes a valve driver unnecessary.
(5) In the tank unit 26, when viewed in the vertical direction Z, the first chamber 62 and the second chamber 68 overlap at least partially. This structure realizes an efficient layout of the first chamber 62 and the second chamber 68.
(6) The tank unit 26 further includes the outlet portion 74 that is in communication with the second chamber 68, the liquid stored in the second chamber 68 being configured to flow out via the outlet portion 74 toward the liquid ejecting head 23; and the second inlet portion 75 that is in communication with the first chamber 62, the liquid collected from the liquid ejecting head 23 being configured to flow in via the second inlet portion 75. This structure makes it possible to keep the liquid surface of the first chamber 62 and the liquid surface of the second chamber 68 at the same surface level.
(7) The tank unit 26 further includes the filter 100 provided between the second chamber 68 and the outlet portion 74 and configured to trap foreign objects contained in the liquid. This structure makes it possible to trap foreign objects mixed in the process of replacement of the liquid container 24, foreign objects mixed in the process of circulation, and the like.
(8) In the tank unit 26, the first chamber 62 has the cover portion 88 inside; and the cover portion 88 is provided over the second inlet portion 75 formed in a lower surface inside the first chamber 62. This structure makes it possible to prevent ink collected into the first chamber 62 from being scattered in the first chamber 62 all around.
(9) The liquid ejecting apparatus includes the liquid ejecting head 23 configured to eject liquid; the tank unit 26; the supply flow passage 37 that provides communication between the outlet portion 74 and the liquid ejecting head 23; and the collection flow passage 39 that provides communication between the liquid ejecting head 23 and second inlet portion 75. The same effects as those of the tank unit 26 can be obtained from the liquid ejecting apparatus 11 having this structure.
(10) The liquid ejecting apparatus 11 further includes the tilt detecting portion 98 that detects a tilt of the tank unit 26. This structure makes it possible to reduce an amount of change in the liquid surface due to a tilt. Therefore, it is possible to reduce variation in liquid surface detection.
(11) The liquid ejecting apparatus 11 further includes the pressurizing portion 47 that is in communication with the second opening-to-atmosphere portion 69 and is configured to apply pressure to the inside of the second chamber 68. This structure makes it possible to perform pressurization cleaning.
The present embodiment may be modified as described below. The present embodiment and the following modification examples may be combined with one another as long as they are not technically contradictory to one another.
The first inlet portion 60 may have a conduit such as a pipe, a hose, a tube, etc. extending in such a way as to have a directional component in the vertical direction Z inside the first chamber 62.
The opening plane of the opening portion 603 may be a horizontal plane. The opening plane of the opening portion 603 may be inclined in a direction that is the opposite of the direction illustrated in
The first inlet portion 60 may extend in the vertical direction Z without any inclination.
The inlet passage 601 of the first inlet portion 60 may be a curved flow passage. It is sufficient as long as the first inlet portion 60 is connected via the opening portion 603 at some midpoint in the vertical direction Z of the first chamber 62. As long as this is met, the flow-passage shape of the inlet passage 601 from the inlet 60a of the first inlet portion 60 to the opening portion 603 may be any shape. That is, it is sufficient as long as the lower end of the regulating portion 602 serving as a partition between the first chamber 62 and the inlet passage 601 is at some midpoint in the vertical direction Z of the first chamber 62. The opening plane of the opening portion 603 as viewed in the direction along the Y axis may be inclined with respect to the horizontal plane. In this case, the level of the first liquid surface 66 is defined by the highest part of the opening plane of the opening portion 603 as viewed in the direction along the Y axis.
The on-off valve 36 may be controlled by the control portion 19. The on-off valve 36 may be, for example, an electromagnetic valve. The on-off valve 36 may be a flow regulating valve whose flow at the time of opening can be regulated.
The pressurizing portion 47 is not limited to a tube pump. It may be any other kind of pump. For example, it may be a diaphragm pump, a gear pump, or the like.
The tank unit 26 is not limited to an internal tank unit disposed inside the body of the liquid ejecting apparatus 11. The tank unit 26 may be an external tank unit connected to the body through a tube or the like.
The liquid container 24 is not limited to a cartridge such as an ink cartridge. The liquid container 24 may be a tank configured to be detachably attached to the attachment portion 28.
The first reservoir portion 33 or the second reservoir portion 35 may have a window portion through which the user is able to visually confirm the amount of liquid.
In the embodiment, the on-off valve 36 may be omitted. For example, both of the first chamber 62 and the second chamber 68 may be pressurized when cleaning is performed. Such a technical concept is also encompassed within the scope of the embodiment. Even when modified as in such a technical concept, it is possible to provide the tank unit 26 and the liquid ejecting apparatus 11 capable of adjusting the liquid surface of the two reservoir chambers 62 and 68 into an appropriate level with a simple structure.
The second inlet portion 75 may be provided on the second reservoir portion 35, and the liquid coming from the liquid ejecting head 23 may return to the second chamber 68 through the collection flow passage 39 when the liquid is circulated.
The liquid ejecting apparatus may be an ink-jet textile printing apparatus. The textile printing apparatus may include the tank unit 26.
The cleaning may be suction cleaning, instead of pressurization cleaning. In the suction cleaning, a cap is brought in contact with the periphery of the nozzle surface 21 of the liquid ejecting head 23 in such a way as to enclose all of the nozzles 22. Liquid is forcibly discharged through the nozzles by making the pressure of the closed space enclosed by the cap and the nozzle surface 21 negative by driving a suction pump.
The liquid ejecting apparatus 11 may be configured to eject any other kind of liquid, instead of ink. The state of liquid ejected in the form of a micro droplet from the liquid ejecting apparatus encompasses a particulate droplet, a tear-shaped droplet, and a droplet that forms a thready tail. “Liquid” mentioned herein may be made of any material that can be ejected from the liquid ejecting apparatus. For example, “liquid” may be any matter that is in a liquid phase, including but not limited to: a matter that is in a state of liquid having high viscosity or low viscosity, fluid such as sol or gel water, other inorganic solvent or organic solvent, solution, liquid resin, liquid metal, metal melt, etc. “Liquid” encompasses not only liquid as a state of matter but also liquid made as a result of dissolution, dispersion, or mixture of particles of a functional material made of a solid such as pigment or metal particles, etc. into/with a solvent. Ink described in the foregoing embodiment, pretreatment liquid, and post-treatment liquid, etc. are typical examples of “liquid”.
Technical concepts derivable from the foregoing embodiment and from its modification examples, and the operational effects thereof, will be described below.
(A) A tank unit is configured such that liquid supplied from a liquid container flows into it and the liquid flows out of it toward a liquid ejecting head configured to eject the liquid. The tank unit includes: a first inlet portion via which the liquid supplied from the liquid container flows in; a first chamber configured to store the liquid that flows in via the first inlet portion; a first opening-to-atmosphere portion configured to open an inside of the first chamber to atmosphere; an outlet flow passage to which one end is connected to the first chamber; a second chamber connected to the other end of the outlet flow passage and configured to store the liquid supplied from the first chamber; a second opening-to-atmosphere portion configured to open an inside of the second chamber to atmosphere; and an on-off valve configured to open and close the outlet flow passage, wherein the first inlet portion is connected to the first chamber via an opening portion at some midpoint in a vertical direction of the first chamber.
With this structure, it is possible to adjust the liquid surface of the two reservoir chambers into an appropriate level without any need for performing supply control, etc.
(B) In the above tank unit, the opening portion may be located below the center inside the first chamber in the vertical direction.
With this structure, when there is liquid movement between the first chamber, the second chamber, and the liquid container due to an ambient change, etc., it is possible to prevent an overflow of the liquid from the reservoir chamber, etc.
(C) The above tank unit may further include a liquid surface detecting portion configured to detect a surface level of the liquid stored in the first chamber.
With this structure, it is possible to detect that the liquid left in the liquid container has become small, and it is possible to prevent the overflow of the liquid stored in the first chamber.
(D) In the above tank unit, the on-off valve includes a one-way valve that tolerates flow of the liquid from the first chamber toward the second chamber and does not tolerate flow of the liquid from the second chamber toward the first chamber.
This structure makes a valve driver unnecessary.
(E) In the above tank unit, when viewed in the vertical direction, the first chamber and the second chamber may overlap at least partially.
This structure realizes an efficient layout of the first chamber and the second chamber.
(F) The above tank unit may further include: an outlet portion that is in communication with the second chamber, the liquid stored in the second chamber being configured to flow out via the outlet portion toward the liquid ejecting head; and a second inlet portion that is in communication with the first chamber, the liquid collected from the liquid ejecting head being configured to flow in via the second inlet portion.
This structure makes it possible to keep the liquid surface of the first chamber and the liquid surface of the second chamber at the same surface level.
(G) The above tank unit may further include: a filter provided between the second chamber and the outlet portion and configured to trap foreign objects contained in the liquid.
This structure makes it possible to trap foreign objects mixed in the process of replacement of the liquid container, foreign objects mixed in the process of circulation, and the like.
(H) In the above tank unit, the first chamber may have a cover portion inside; and the cover portion may be provided over the second inlet portion formed in a lower surface inside the first chamber.
This structure makes it possible to prevent ink collected into the first chamber from being scattered in the first chamber all around.
(I) A liquid ejecting apparatus includes: a liquid ejecting head configured to eject liquid; the above tank unit; a supply flow passage that provides communication between the outlet portion and the liquid ejecting head; and a collection flow passage that provides communication between the liquid ejecting head and second inlet portion.
The same effects as those of the above tank unit can be obtained from the liquid ejecting apparatus having this structure.
(J) The above liquid ejecting apparatus may further include: a tilt detecting portion that detects a tilt of the tank unit.
This structure makes it possible to reduce an amount of change in the liquid surface due to a tilt. Therefore, it is possible to reduce variation in liquid surface detection.
(K) The above liquid ejecting apparatus may further include: a pressurizing portion that is in communication with the second opening-to-atmosphere portion and is configured to apply pressure to an inside of the second chamber.
This structure makes it possible to perform pressurization cleaning.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2021-169380 | Oct 2021 | JP | national |
