JP6904066B2 - Liquid tank - Google Patents

Description

The present invention relates to a liquid tank technique.

Conventionally, a technique is known in which an ink tank arranged on the side surface of an inkjet recording device, an ejection head to which ink is supplied from the ink tank, and an ink supply path for communicating the ink tank and the ejection head are provided. (Patent Document 1).

Japanese Unexamined Patent Publication No. 2016-155348

In the conventional technique, a filter unit for storing ink is arranged in the middle of the flow path from the ink supply path to the ejection head. The filter unit has a function of discharging air bubbles by sucking ink from the discharge head side. In the conventional technique, the filter portion may have a complicated structure and become large due to the function for discharging air bubbles. Therefore, when the filter unit is detachably mounted on the carriage, a technique capable of suppressing the increase in size of the filter unit is desired. Further, when the structure of the filter portion becomes complicated, there is a possibility that the ink cannot be efficiently supplied to the ejection head. Therefore, a technique capable of efficiently supplying ink to the ejection head is desired. Further, these demands are not limited to the filter unit arranged on the carriage, but are common to the liquid tank that is detachably mounted on the carriage provided with the liquid injection head and stores the liquid to be supplied to the liquid injection head. To do.

The present invention has been made to solve at least a part of the above-mentioned problems, and can be realized as the following forms or application examples.

(1) According to one embodiment of the present invention, there is provided a liquid tank that is detachably mounted on a carriage provided with a liquid injection head. This liquid tank has a liquid supply port for receiving the liquid introduction needle portion of the liquid injection head, and houses the liquid supply portion to which the liquid introduction needle portion is detachably connected and the liquid to be supplied to the liquid supply portion. A liquid communication flow path that connects a possible first liquid chamber, the first liquid chamber, and the liquid supply unit, and can supply the liquid in the first liquid chamber to the liquid supply unit, and is the liquid. In the mounted state in which the tank is mounted on the carriage, the liquid communication flow path that forms a convex flow path on the upper side is connected to the first liquid chamber and the liquid supply unit, and the first liquid chamber is connected to the first liquid chamber. An air communication flow path capable of flowing air between the liquid supply unit and the first liquid chamber at a position higher than the connection position between the liquid communication flow path and the first liquid chamber in the mounted state. The liquid communication flow path is provided with an air communication flow path connected to the above, and the liquid communication flow path is an upstream end connected to the first liquid chamber in the flow direction of the liquid from the liquid tank to the liquid injection head. An ascending flow path located on the downstream side of the upstream end and extending upward in the mounted state, a descending flow path located on the downstream side of the ascending flow path and extending downward in the mounted state, and the descending flow. It has a downstream end located on the downstream side of the road and connected to the liquid supply unit, and the liquid supply unit is located below the downstream end in the mounted state and is located at the liquid supply port. Extends downward.
According to this form, the liquid supply unit is located below the downstream end in the mounted state and extends downward toward the liquid supply port. As a result, it is possible to prevent the liquid tank from becoming large in the horizontal direction. Further, as a result, the liquid can be smoothly circulated from the liquid supply unit to the liquid injection head, so that the liquid can be efficiently supplied to the liquid injection head.

(2) In the above embodiment, the second liquid chamber capable of accommodating the liquid to be supplied to the first liquid chamber, the first liquid chamber and the second liquid chamber are connected to each other, and the second liquid chamber is connected. A connection flow path capable of supplying the liquid in the liquid chamber to the first liquid chamber, a liquid injection unit capable of injecting the liquid into the second liquid chamber, and an air communication unit for communicating the second liquid chamber with the atmosphere. And may have. According to this form, since the liquid tank has an air communication portion, when the liquid is injected into the second liquid chamber from the liquid injection portion, the air in the second liquid chamber can be discharged to the outside. As a result, the possibility of air (air bubbles) flowing from the second liquid chamber to the first liquid chamber can be reduced.

(3) In the above embodiment, the connection flow path forms one end and has an inlet opening connected to the first liquid chamber, and the liquid tank further opens and closes the inlet opening. It has a valve mechanism for controlling the inflow of the liquid from the second liquid chamber to the first liquid chamber, and the inlet opening is arranged at a position lower than the upstream end in the mounted state. Good. Here, the liquid may contain a component that agglomerates and becomes a foreign substance when it comes into contact with a gas and receives a pressure change due to opening and closing of a valve mechanism. According to this form, since the inlet opening is arranged at a position lower than the upstream end in the mounted state, it is possible to prevent the liquid water level from becoming lower than that of the inlet opening. Therefore, the presence of gas around the inlet opening can be suppressed, and the possibility of foreign matter being generated around the inlet opening can be reduced. This makes it possible to reduce the possibility of foreign matter flowing into the liquid injection head.

(4) In the above embodiment, the valve mechanism may be opened when at least the first liquid chamber becomes negative pressure. According to this form, the opening / closing operation of the valve mechanism can be stabilized.

(5) In the above embodiment, the volume of the first liquid chamber may be smaller than that of the second liquid chamber. According to this form, since the volume of the first liquid chamber is smaller than that of the second liquid chamber, the amount of air sucked can be reduced when the air in the first liquid chamber is sucked and discharged to the liquid injection head. As a result, the air suction time can be shortened.

(6) The tank body having the above-described embodiment and further having one side wall, and the first liquid chamber, the liquid communication flow path, and the air communication flow path are formed on one side of the one side wall. The second liquid chamber may be formed on the other side opposite to one side of the one side wall. According to this form, since the first liquid chamber and the second liquid chamber can be arranged by efficiently utilizing the space of the liquid tank, it is possible to suppress the increase in size of the liquid tank.

(7) In the above embodiment, when the liquid tank is viewed from one side of the one side wall, the liquid injection port and the liquid supply port may be arranged at diagonal positions. According to this form, it is possible to prevent the distance from the liquid injection part to the liquid supply port from becoming short, so that even if bubbles are generated when the liquid is injected from the liquid injection part into the second liquid chamber, the liquid supply port The possibility of bubbles reaching the surface can be reduced. As a result, it is possible to reduce the number of bubbles staying in the vicinity of the liquid supply port in the liquid supply unit, so that the possibility of bubbles flowing into the liquid injection head can be reduced. Further, since the flow path through which the liquid flows from the liquid injection portion to the liquid supply port can be efficiently arranged, it is possible to suppress the increase in size of the liquid tank.

(8) In the above embodiment, the connection flow path is connected to the second liquid chamber and has a filter chamber located below the second liquid chamber in the mounted state, and the filter chamber has a filter chamber. In the mounted state, the inflow opening connected to the second liquid chamber, the first portion of the filter chamber located on the upper side including the inflow opening, and the second portion located on the lower side of the first portion. It may have a filter member which is divided into portions and is located below the inflow opening. According to this form, since the bubbles adhering to the filter can be guided to the second liquid chamber, the possibility that the bubbles flow out to the first liquid chamber and the liquid supply unit can be reduced.

(9) In the above embodiment, the air communication flow path may be connected to the uppermost portion of the first liquid chamber in the mounted state. According to this form, the possibility of liquid flowing into the air communication flow path can be reduced. Further, the air on the liquid supply unit side can be smoothly flowed into the first liquid chamber through the air communication flow path.

The present invention can be realized in various forms other than the liquid tank. For example, it can be realized in the form of a method for manufacturing a liquid tank, a liquid injection device provided with a liquid tank, or the like.

FIG. 6 is an external view of a liquid injection device including a liquid tank as one embodiment of the present invention. The schematic diagram which shows the internal structure of the liquid injection device. A conceptual diagram mainly for explaining a flow path configuration of a liquid tank. Partially disassembled perspective view of the liquid tank. First perspective view of the tank body. A second perspective view of the tank body. A third perspective view of the tank body. The first figure which looked at the tank body from the -Y axis direction side. The second figure which looked at the tank body from the -Y axis direction side. The figure which looked at the tank body from the + Y axis direction side. Schematic diagram of the filter chamber. The first figure for demonstrating the initial filling of a liquid. The second figure for demonstrating the initial filling of a liquid. FIG. 3 for explaining the initial filling of the liquid. The first figure for demonstrating the liquid tank after the initial filling of a liquid. The second figure for demonstrating the liquid tank after the initial filling of a liquid. FIG. 3 for explaining the liquid tank after the initial filling of the liquid. FIG. 4 for explaining the liquid tank after the initial filling of the liquid. FIG. 5 for explaining the liquid tank after the initial filling of the liquid.

A. Embodiment:
A-1. Liquid injection device configuration:
FIG. 1 is an external view of a liquid injection device 1 including a liquid tank as one embodiment of the present invention. In FIG. 1, three spatial axes orthogonal to each other, the X-axis, the Y-axis, and the Z-axis, are drawn. The direction along the X-axis is the X-axis direction, the direction along the Y-axis is the Y-axis direction, and the direction along the Z-axis is the Z-axis direction (vertical direction). The liquid injection device 1 is installed on a plane (XY plane) parallel to the X-axis direction and the Y-axis direction. The + Z-axis direction is the vertical downward direction, and the −Z-axis direction is the vertical upward direction. In the other figures described below, the X-axis, the Y-axis, and the Z-axis are attached as necessary.

The liquid injection device 1 is a so-called inkjet printer, and prints on a recording medium by injecting ink as a liquid onto a recording medium such as paper. The liquid injection device 1 of the present embodiment is a printer that performs black-and-white printing using black ink as a liquid.

The liquid injection device 1 includes an outer shell 100 that forms an outer surface. The outer shell 100 has a substantially rectangular parallelepiped shape, and has an upper surface (first surface, first wall) 101, a lower surface (second surface, second wall) 102, and a front surface (third surface, third wall) 103. It has a back surface (fourth surface, fourth wall) 104, a right side surface (fifth surface, fifth wall) 105, and a left side surface (sixth surface, sixth wall) 106. The upper surface 101 and the lower surface 102 face each other in the Z-axis direction. The front surface 103 and the back surface 104 face each other in the X-axis direction. The right side surface 105 and the left side surface 106 face each other in the Y-axis direction. The front surface 103, the back surface 104, the right side surface 105, and the left side surface 106 are surfaces that are substantially perpendicular to the installation surface of the liquid injection device 1, respectively. The upper surface 101 and the lower surface 102 are surfaces that are substantially horizontal to the installation surface of the liquid injection device 1, respectively. In the present embodiment, "substantially vertical" and "substantially horizontal" include not only the meaning of being completely "vertical" or "horizontal" but also the meaning of being generally "vertical" or "horizontal". That is, each of the surfaces 101 to 106 is not a perfect flat surface but allows unevenness and the like, and may be generally "vertical" or generally "horizontal" in appearance.

The liquid injection device 1 further includes a front cover 2, a discharge port 3, an operation unit 4, and a top cover 6. The front cover 2 forms a part of the front surface 103, is pivotally supported at the lower end portion, and can be opened and closed by rotating the upper end portion side. In FIG. 1, the front cover 2 is in an open state. By opening the front cover 2, the discharge port 3 is exposed.

The discharge port 3 is a portion where the recording medium is discharged. The recording medium may be arranged on a tray provided on the back surface 104 side (not shown). Printing on the recording medium is executed by ejecting the liquid onto the recording medium while the recording medium arranged on the tray is conveyed to the inside of the outer shell 100.

The operation unit 4 is a button that receives various operations from the user. Examples of various operations include an operation for starting printing of the liquid injection device 1 and an operation for executing a discharge operation for discharging the fluid in the liquid tank to the outside, which will be described later.

The top cover 6 constitutes the top 101. The upper surface cover 6 is pivotally supported at the end on the back surface 104 side, and can be opened and closed by rotating the front surface 103 side. By opening the top cover 6, it is possible to check the internal state of the liquid injection device 1, perform the attachment / detachment operation of the liquid tank described later, and inject the liquid into the liquid tank.

A device-side window 103a is formed in a region of the front surface 103 that overlaps with the home position of the carriage 19 in the Y-axis direction (reciprocating direction of the carriage 19 described later). In the present embodiment, the device side window portion 103a is located at a position different from that of the front cover 2 and is arranged on the −Y axis direction side of the front cover 2. The device-side window 103a is provided so that the user can visually recognize the front surface (visual surface) 404 of the liquid tank 30 mounted on the carriage 19 located at the home position from the outside. Further, a sign M1 is provided on the front surface 404. The device side window portion 103a may be, for example, a through hole penetrating the front surface 103, or may be a transparent member. The label M1 is an element for indicating a standard for the water level of the liquid contained in the liquid tank 30, and in the present embodiment, it indicates an upper limit standard. Details of the label M1 will be described later. If the front surface 404 of the liquid tank 30 in the home position can be visually recognized from the outside, the device side window portion 103a may not be provided on the front surface 103. For example, the device-side window portion 103a may be provided on the upper surface 101. In this case, the user can visually recognize the front surface 404 of the liquid tank 30 by visually recognizing the device side window portion 103a from the front upper side.

FIG. 2 is a schematic view showing the internal configuration of the liquid injection device 1. The liquid injection device 1 includes a control unit 17, a carriage 19 provided with a liquid injection head 12, and a liquid tank 30 detachably mounted on the carriage 19 inside the outer shell 100. The control unit 17 controls various operations (for example, printing operation) of the liquid injection device 1.

The carriage 19 has a mounting portion 11 arranged on the liquid injection head 12. The mounting portion 11 has, for example, a concave shape that opens in the + Z axis direction, and forms a mounting space in which the liquid tank 30 is mounted. The mounting portion 11 has a liquid introduction needle portion 122 that projects in the + Z axis direction from the lower surface that partitions the mounting space. The liquid introduction needle portion 122 is connected to the liquid tank 30. The liquid introduction needle portion 122 is hollow, and a communication hole that communicates with the inside is formed on the tip side. The liquid supplied from the liquid tank 30 flows through the communication hole of the liquid introduction needle portion 122 inside the liquid introduction needle portion 122. The liquid injection head 12 communicates with the liquid introduction needle portion 122 and injects the liquid (black ink in this embodiment) supplied from the liquid tank 30 onto the recording medium 20 (for example, printing paper).

Further, the mounting portion 11 has a mounting portion side window portion 11a for the user to visually recognize the front surface (visual recognition surface) 404 including the sign M1. The mounting portion side window portion 11a is provided at least at a position facing the sign M1 of the liquid tank 30. The mounting portion side window portion 11a may be, for example, a through hole penetrating the wall forming the mounting portion 11, or may be a transparent member. When the carriage 19 is located at the home position, the user can visually recognize the front surface (visual surface) 404 having the sign M1 via the device side window portion 103a (FIG. 1) and the mounting portion side window portion 11a.

The carriage 19 of the liquid injection head 12 is driven by a drive mechanism (not shown), and repeats reciprocating movement on the recording medium 20 while being guided by a guide rail 13 extending along the Y-axis direction. Further, the liquid injection device 1 has a transport mechanism for transporting the recording medium 20 toward the discharge port 3 (FIG. 1). An image or the like is printed on the recording medium 20 by ejecting the liquid from the liquid injection head 12 in accordance with the movement of the carriage 19 reciprocating and the movement of the recording medium 20 being conveyed.

The liquid tank 30 houses the liquid to be supplied to the liquid injection head 12. The liquid contained in the present embodiment is a black ink, which is an ink in which pigment particles are dissolved in a solvent. The liquid tank 30 is detachably connected to the liquid introduction needle portion 122. By connecting the liquid tank 30 to the liquid introduction needle portion 122, the liquid in the liquid tank 30 can be circulated to the liquid introduction needle portion 122.

The liquid injection device 1 further includes a discharge unit 18 that executes an operation (discharge operation) for periodically sucking a fluid (for example, liquid or air) from the liquid injection head 12.

The discharge unit 18 is arranged inside the outer shell 100. The discharge unit 18 includes a cap 14, a suction tube 15, and a suction pump 16. While the liquid injection device 1 is not performing the printing operation, the carriage 19 is arranged at the home position which is a position outside the moving area in the printing operation.

The cap 14 is a bottomed box-shaped member arranged below the home position. The cap 14 can be moved in the Z-axis direction (vertical direction) by an elevating mechanism (not shown). The cap 14 is pressed against the lower surface side of the liquid injection head 12 by ascending. As a result, the cap 14 forms a closed space so as to cover the nozzle hole formed on the lower surface of the liquid injection head 12 (closed space state). Due to this closed space, it is possible to prevent the ink in the nozzle 12 from drying.

The suction tube 15 communicates the cap 14 (specifically, a through hole formed in the bottom surface of the cap 14) with the suction pump 16. The suction pump 16 sucks the fluid (liquid or air) of the liquid injection head 12 or the liquid tank 30 through the suction tube 15 by driving in a closed space state. As a result, the liquid injection head 12 can be initially filled with the liquid, and the deteriorated liquid (dry and thickened liquid) in the liquid injection head 12 can be sucked out.

A-2. Outline of liquid tank:
FIG. 3 is a conceptual diagram mainly for explaining the flow path configuration of the liquid tank 30. Before explaining the detailed configuration of the liquid tank 30, a schematic description of the liquid tank 30 will be given below with reference to FIG. Further, the "upstream side" and "downstream side" used in the following description are based on the flow direction of the liquid from the liquid tank 30 to the liquid injection head 12. In FIG. 3, dots are attached to the region where the liquid exists.

The liquid tank 30 has a second liquid chamber 52, a connecting flow path 54, a first liquid chamber 51, a liquid communication flow path 80, and a liquid supply unit 50, in order from the upstream side, as a flow path through which the liquid flows. To be equipped with. Further, the liquid tank 30 includes an air communication flow path 70 as a flow path through which air flows.

Liquid can be injected into the second liquid chamber 52 from the outside through the liquid injection unit 42. Further, the second liquid chamber 52 communicates with the atmosphere by an atmospheric communication unit 300 including an atmospheric opening unit 44 at one end. The second liquid chamber 52 can accommodate the liquid to be supplied to the first liquid chamber 51.

The connection flow path 54 connects the first liquid chamber 51 and the second liquid chamber 52, and can supply the liquid in the second liquid chamber 52 to the first liquid chamber 51. The connection flow path 54 has a filter chamber 542, an intermediate flow path 544, and a valve arrangement chamber 546 in this order from the upstream side. The filter chamber 542 is connected to the second liquid chamber 52. Specifically, the filter chamber 542 has an inflow opening 548 that opens in the second liquid chamber 52. That is, the inflow opening 548 is connected to the second liquid chamber 52. The filter chamber 542 has a filter member 541 that divides the filter chamber 542 into an upstream side and a downstream side. The filter member 541 captures foreign matter in the liquid flowing from the upstream side to the downstream side and suppresses the foreign matter from flowing to the downstream side. As a result, the possibility of foreign matter flowing into the liquid injection head 12 can be reduced, so that clogging of the liquid injection head 12 and occurrence of liquid injection failure can be reduced. Further, since the filter chamber 542 is arranged on the upstream side of the valve arrangement chamber 546, the possibility that foreign matter flows into the valve arrangement chamber 546 is reduced. As a result, it is possible to reduce the possibility that a foreign matter causes a problem in the opening / closing operation of the valve mechanism, which will be described later. The filter member 541 is a filter formed of plate-shaped stainless steel, and has a plurality of pores capable of allowing a liquid to pass through and suppressing the passage of foreign matter. The filter member 541 may be formed of another member as long as the liquid can be passed and the passage of foreign matter can be suppressed.

The intermediate flow path 544 is a flow path that communicates the filter chamber 542 and the valve arrangement chamber 546. The valve arrangement chamber 546 has an inlet opening 547 connected to the first liquid chamber 51. That is, the inlet opening 547 forms one end (downstream end) of the connection flow path 54. The inlet opening 547 forms a through hole having a circular cross section of the flow path. In the valve arrangement chamber 546, a part of the valve mechanism 60 for opening and closing the inlet opening 547 to control the inflow of liquid from the second liquid chamber 52 to the first liquid chamber 51 is arranged. When the valve mechanism 60 is opened, the second liquid chamber 52 and the first liquid chamber 51 communicate with each other, and the liquid in the second liquid chamber 52 flows into the first liquid chamber 51. Further, when the valve mechanism 60 is closed, the second liquid chamber 52 and the first liquid chamber 51 are in a non-communication state.

The valve mechanism 60 includes a valve body 64, a rod 67, a pressure receiving plate 68, a first urging member 62, and a second urging member 65. The valve body 64 is a disk-shaped member and is arranged in the valve arrangement chamber 546. The valve body 64 faces the inlet opening 547 with the annular seal member 66 interposed therebetween. The seal member 66 is arranged on the peripheral edge of the inlet opening 547 so as to surround the inlet opening 547. When the valve body 64 comes into contact with the seal member 66, the valve arrangement chamber 546 and the first liquid chamber 51 are in a non-communication state. When the valve body 64 is separated from the seal member 66, the valve arrangement chamber 546 and the first liquid chamber 51 are in a communicating state. The rod 67 is a rod-shaped member having one end connected to the valve body 64 and the other end connected to the pressure receiving plate 68. The rod 67 is inserted through the inlet opening 547. The pressure receiving plate 68 is a disk-shaped member. The pressure receiving plate 68 comes into contact with the flexible first film 91 that partitions the first liquid chamber 51 by the urging force of the first urging member 62 and the second urging member 65.

The first urging member 62 is a compression coil spring arranged in the valve arrangement chamber 546. The first urging member 62 urges the valve body 64 toward the seal member 66 side. The second urging member 65 is a compression coil spring arranged in the first liquid chamber 51. The second urging member 65 urges the pressure receiving plate 68 toward the first film 91 side. The liquid in the first liquid chamber 51 is supplied and consumed by the liquid injection head 12, so that when the inside of the first liquid chamber 51 becomes negative pressure, the first urging member 62 and the second urging member 62 Against the urging force of 65, the pressure receiving plate 68, the rod 67, and the valve body 64 are urged by the first film 91 in a direction away from the seal member 66 and the inlet opening 547. As a result, when the valve body 64 is separated from the seal member 66, the valve mechanism 60 is opened, and the valve arrangement chamber 546 and the first liquid chamber 51 are in a communicating state. In the communicating state, when the liquid is supplied from the second liquid chamber 52 to the first liquid chamber 51 and the pressure in the first liquid chamber 51 rises to some extent (for example, when it becomes larger than the negative pressure), the first Due to the urging force of the urging member 62 and the second urging member 65, the valve body 64 moves toward the seal member 66 and comes into contact with the seal member 66. As a result, the valve mechanism 60 is closed, and the valve arrangement chamber 546 and the first liquid chamber 51 are in a non-communication state. As described above, since the valve mechanism 60 is opened when at least the inside of the first liquid chamber 51 becomes negative pressure, the pressure in the first liquid chamber 51 can be stabilized. That is, the height position of the nozzle hole of the liquid injection head 12 and the height position of the nozzle hole of the liquid injection head 12 are compared with the case where the valve mechanism that opens when the pressure difference between the upstream side and the downstream side of the valve body 64 becomes larger than a predetermined value is used. It is possible to suppress the fluctuation of the pressure in the first liquid chamber 51 according to the difference (water head difference) from the liquid level height position of the second liquid chamber 52. As a result, the liquid can be stably supplied from the second liquid chamber 52 to the first liquid chamber 51.

The first liquid chamber 51 can accommodate the liquid to be supplied to the liquid supply unit 50. The liquid communication flow path 80 connects the first liquid chamber 51 and the liquid supply unit 50, and can supply the liquid in the first liquid chamber 51 to the liquid supply unit 50. The air communication flow path 70 connects the first liquid chamber 51 and the liquid supply unit 50, and air can flow between the first liquid chamber 51 and the liquid supply unit 50.

The liquid supply unit 50 has a liquid supply port 505 at the downstream end. The liquid supply port 505 receives the liquid introduction needle portion 122. The liquid supply unit 50 is detachably connected to the liquid introduction needle unit 122 of the liquid injection head 12. Specifically, the liquid supply unit 50 is connected to the liquid introduction needle unit 122 by inserting the liquid introduction needle unit 122 into the liquid supply unit 50 via the liquid supply port 505 of the liquid supply unit 50. As a result, the liquid can be supplied from the liquid supply unit 50 to the liquid introduction needle unit 122.

Inside the liquid supply unit 50, a supply unit valve mechanism 200 for opening and closing the flow path of the liquid supply unit 50 is arranged. The supply unit valve mechanism 200 includes a valve seat 202, a valve body 203, and a spring 204 in this order from the downstream side.

The valve seat 202 is a substantially annular member. The valve seat 202 is made of, for example, an elastic body such as rubber or an elastomer. The valve seat 202 is press-fitted into the liquid supply unit 50. The valve body 203 is a substantially columnar member. The valve body 203 closes the hole (valve hole) formed in the valve seat 202 in the state before the liquid tank 30 is mounted on the carriage 19 (state before mounting). The spring 204 is a compression coil spring. The spring 204 urges the valve body 203 toward the valve seat 202 side. When the liquid tank 30 is mounted on the carriage 19 and the liquid supply unit 50 is connected to the liquid introduction needle portion 122, the liquid introduction needle portion 122 pushes the valve body 203 upstream. Then, the valve body 203 moves in the direction away from the valve seat 202. As a result, the supply unit valve mechanism 200 is opened, and the liquid can be supplied from the liquid supply unit 50 to the liquid introduction needle unit 122.

A-3. Detailed configuration of the liquid tank 30:
FIG. 4 is a partially exploded perspective view of the liquid tank 30. FIG. 5 is a first perspective view of the tank body 40. FIG. 6 is a second perspective view of the tank body 40. FIG. 7 is a third perspective view of the tank body 40. FIG. 8 is a first view of the tank body 40 as viewed from the −Y axis direction side. FIG. 9 is a second view of the tank body 40 as viewed from the −Y axis direction side. FIG. 10A is a view of the tank body 40 as viewed from the + Y axis direction side. FIG. 10B is a schematic view of the filter chamber 542. In FIGS. 5, 6, 7, and 8, the valve mechanism 60 arranged in the tank body 40 is also shown. In FIG. 9, the rod 67 of the valve mechanism 60 is also shown.

As shown in FIG. 4, the liquid tank 30 includes a tank body 40, a first film 91, a second film 92, and a third film 93. The liquid tank 30 has a substantially rectangular parallelepiped shape. In the liquid tank 30, the X-axis direction is the length direction, the Y-axis direction is the width direction, and the Z-axis direction is the height direction.

The liquid tank 30 has an upper surface (first surface, first wall) 401, a lower surface (second surface, second wall) 402, a back surface (third surface, third wall) 403, and a front surface (fourth surface, fourth wall). It has a fourth wall) 404, a left side surface (fifth surface, fifth wall) 405, and a right side surface (sixth surface, fifth wall) 406. In the mounted state in which the liquid tank 30 is mounted on the carriage 19, the upper surface 401 and the lower surface 402 face each other in the Z-axis direction. In the mounted state, the back surface 403 and the front surface 404 face each other in the X-axis direction. In the mounted state, the left side surface 405 and the right side surface 406 face each other in the Y-axis direction. The left side surface 405 is formed by the third film 93. The right side surface 406 is formed by the first film 91. The upper surface 401, the lower surface 402, the back surface 403, and the front surface 404 are formed by the tank body 40. The back surface 403, the front surface 404, the left side surface 405, and the right side surface 406 are surfaces that are substantially perpendicular to the installation surface of the liquid injection device 1, respectively. The upper surface 401 and the lower surface 402 are surfaces that are substantially horizontal to the installation surface of the liquid injection device 1, respectively. Each surface 401 to 406 is not a perfect flat surface, but allows unevenness and the like, and may be generally "vertical" or generally "horizontal" in appearance. Further, the front surface 404 constitutes a visible surface on which the water level of the liquid in the liquid tank 30 (specifically, the second liquid chamber 52) can be visually recognized from the outside. For example, the front surface 404 is formed of a transparent or translucent member. The front surface 404 may be provided with a sign (for example, a scale or a mark) corresponding to a reference (for example, an upper limit or a lower limit) of the water level (liquid level) of the liquid. In the present embodiment, as shown in FIG. 5, a sign M1 corresponding to the upper limit is provided on the front surface 404. For example, when injecting a liquid from the liquid injection unit 42, when the liquid level reaches the label M1 corresponding to the upper limit, the user stops the injection of the liquid. Further, for example, when a sign corresponding to the lower limit (lower limit mark) is provided, when the liquid level of the liquid tank 30 (specifically, the second liquid chamber 52) reaches the lower limit mark, the user injects liquid. The liquid is injected into the second liquid chamber 52 from the part 42.

A lever 59 for attaching / detaching the liquid tank 30 to / from the mounting portion 11 (FIG. 2) of the carriage 19 is provided on the back surface 403. The lever 59 prevents the liquid tank 30 from coming off from the mounting portion 11 by engaging with the mounting portion 11 in the mounted state. The mounting portion 11 is elastically deformable. By pressing the lever 59 toward the back surface 403, the user elastically deforms the lever 59 toward the back surface 403 to release the engagement with the mounting portion 11. By disengaging this engagement, the liquid tank 30 can be removed from the mounting portion 11.

The tank body 40 has a substantially rectangular parallelepiped shape, and is formed of, for example, a synthetic resin such as polypropylene or polystyrene. The first film 91, the second film 92, and the third film 93 are each airtightly attached to different parts of the tank body 40, so that the flow path through which liquid or air flows in the liquid tank 30 can be passed through the tank body. A compartment is formed together with 40.

The tank body 40 (FIG. 6) has a concave shape with an opening on the + Y axis direction side. The tank body 40 has a side wall 408 that forms the bottom of the concave tank body 40. The one side wall 408 is a wall that separates the first liquid chamber 51 and the second liquid chamber 52.

The one side wall 408 is substantially parallel to the X-axis direction and the Z-axis direction. As shown in FIG. 5, a first liquid chamber 51, a liquid communication flow path 80, and an air communication flow path 70 are formed on one side (-Y-axis direction side) of one side wall 408. Further, as shown in FIG. 6, a second liquid chamber 52 is formed on the other side (+ Y-axis direction side) opposite to one side of the one side wall 408. As a result, the space of the liquid tank 30 can be efficiently used to arrange the first liquid chamber 51, the liquid communication flow path 80, the air communication flow path 70, and the second liquid chamber 52, so that the size of the liquid tank 30 can be increased. Can be suppressed.

As shown in FIGS. 4 and 8, the one side wall 408 is formed with a groove for partitioning the air communication flow path 70 and the liquid communication flow path 80, and a recess for forming the first liquid chamber 51. By airtightly attaching the first film 91 to the end surface of the one side wall 408 on the −Y axis direction side, the first liquid chamber 51, the air communication flow path 70, and the liquid communication flow path 80 are partitioned. Further, as shown in FIGS. 4 and 6, the second liquid chamber 52 is formed into a section by airtightly attaching the third film 93 to the + Y-axis side end surface of the tank body 40 facing the one side wall 408. Will be done.

The tank body 40 (FIG. 4) further has a liquid injection section 42. The liquid injection portion 42 extends in the + Z axis direction from the bottom surface 49 of the corner portion 48 where the upper surface 401, the back surface 404, and the left side surface 406 intersect. The liquid injection unit 42 is a tubular member and forms a first flow path and a second flow path. A partition wall 45 is arranged inside the liquid injection portion 42. The partition wall 45 divides the first flow path and the second flow path. At the time of liquid injection, the first flow path functions as a liquid injection path for flowing the liquid into the second liquid chamber 52, and the second flow path functions as an air discharge path for discharging air from the second liquid chamber 52. The liquid injection unit 42 is fitted with a cap (not shown) when the liquid in the liquid tank 30 is used. Further, an atmospheric opening portion 44, which is one end of the atmospheric communication portion 300, is formed on the upper portion of the tank body 40. The air communication unit 300 has a narrow groove-shaped flow path and a buffer chamber that can accommodate ink when it flows back. The other end of the air communication portion 300 is connected to the second liquid chamber 52. As a result, when the liquid tank 30 is used, the second liquid chamber 52 communicates with the atmosphere. Details of the atmospheric communication unit 300 will be described later.

As shown in FIG. 6, the second liquid chamber 52 has a second liquid chamber bottom surface 404fa that forms a bottom surface in the mounted state. The bottom surface 404fa of the second liquid chamber is the inner surface of the bottom surface 402. The bottom surface 404fa of the second liquid chamber is formed with an inflow opening 548 that penetrates along the vertical downward direction (−Z axis direction) in the mounted state. The inflow opening 548 is an upstream end of the filter chamber 542 formed on the lower surface 402.

The filter chamber 542 (FIG. 7) is partitioned by a frame-shaped member 549 protruding from the lower surface 402 and a second film 92 (FIG. 4) airtightly attached to the lower end surface of the frame-shaped member 549. The filter chamber 542 is located below the second liquid chamber 52 (in the −Z axis direction) in the mounted state. A filter member 541 is arranged inside the frame-shaped member 549. In the present embodiment, for example, it is arranged in the frame-shaped arrangement portion 543 (FIG. 10B) formed inside the frame-like member 549. The filter member 541 has a plate shape and is orthogonal to the vertically downward direction (−Z axis direction) in the mounted state. Further, a communication opening 545 communicating with the intermediate flow path 544 is formed at the peripheral edge of the filter member 541 (FIGS. 7 and 10B). The liquid in the second liquid chamber 52 flows along the −Z axis direction as shown by the arrow Y1, passes through the inflow opening 548 and the filter member 541, and the liquid passing through the filter member 541 flows along the + Z axis direction. It passes through the communication opening 545. The liquid that has passed through the communication opening 545 flows into the intermediate flow path 544. As described above, in the mounted state, the filter member 541 (FIG. 10B) has a first portion 542A located above the filter chamber 542 including the inflow opening 548 and a second portion 542A located below the first portion 542A. It is divided into a portion 542B. Further, the filter member 541 is located below the inflow opening 548 in the mounted state. As a result, even if air bubbles adhere to the filter member 541, the adhered air bubbles can be guided to the second liquid chamber 52 through the inflow opening 548, so that the air bubbles flow out to the first liquid chamber 51 and the liquid supply unit 50. The possibility of doing so can be reduced.

The intermediate flow path 544 and the valve arrangement chamber 546 (FIG. 6) are formed in the second liquid chamber 52. The intermediate flow path 544 and the valve arrangement chamber 546 include a one side wall 408, a flow path wall 46 rising from the one side wall 408 toward the opening side (+ Y-axis direction side) of the concave tank body 40, and the flow path wall 46. The partition is formed by a film (not shown) airtightly attached to the end surface 466 on the + Y axis direction side. Single hatching is attached to the end face 466 to which the film is attached.

The intermediate flow path 544 extends in a direction having a horizontal component and a vertically upward component in the mounted state. In another embodiment, the intermediate flow path 544 may be formed so as to extend vertically upward. The valve arrangement chamber 546 has a substantially circular shape when the tank body 40 is viewed from the + Y axis direction side. An inlet opening 547 is formed in the valve arrangement chamber 546. Specifically, the inlet opening 547 is a through hole penetrating the one side wall 408.

The first liquid chamber 51 (FIG. 8) is formed on one side wall 408 and is airtightly attached to a recess that opens in the horizontal direction (in the present embodiment, the −Y axis direction) and an end surface of the recess on the −Y axis direction side. It is formed by the first film 91 (FIG. 4) formed. The volume (maximum volume) of the first liquid chamber 51 is smaller than that of the second liquid chamber 52 (maximum volume). The first liquid chamber 51 has a side wall 515 facing the first film 91, a bottom wall 517 located vertically downward in the mounted state, and an arc shape extending vertically upward from the bottom wall 517 in the mounted state. It has a peripheral wall 518 and. An entrance opening 547 is formed in the side wall 515. The peripheral wall 518 has a portion facing the bottom wall 517. The peripheral wall 518 has an uppermost portion 519 arranged at the highest position among the first liquid chambers 51 in the mounted state.

The liquid communication flow path 80 (FIG. 8) forms a convex flow path on the upper side in the mounted state. In the present embodiment, the liquid communication flow path 80 forms an inverted U-shaped flow path in the mounted state. The liquid communication flow path 80 has an upstream end 82, an ascending flow path 83, a liquid intermediate flow path 86, a descending flow path 84, and a downstream end 85 in order from the upstream side in the liquid flow direction.

The upstream end 82 is an opening formed in the peripheral wall 518 of the first liquid chamber 51 and is connected to the first liquid chamber 51. The ascending flow path 83 is located on the downstream side of the upstream end 82, and extends upward in the mounted state and the flow direction. In the present embodiment, the ascending flow path 83 extends vertically upward from the upstream end 82. In another embodiment, the ascending flow path 83 may extend diagonally as long as it has an upper component. Here, in the mounted state, the inlet opening 547 is arranged at a position lower than the upstream end 82. That is, the entrance opening 547 is arranged at a position closer to the bottom wall 517 than the upstream end 82.

Here, since the liquid contains pigment particles, the pigment particles may aggregate and become foreign matter when the liquid comes into contact with the gas and receives a pressure change due to the opening and closing of the valve mechanism 60. As described above, since the inlet opening 547 is arranged at a position lower than the upstream end 82 in the mounted state, it is possible to prevent the liquid water level from becoming lower than that of the inlet opening 547. Therefore, since the presence of gas around the inlet opening 547 can be suppressed, the possibility that foreign matter is generated around the inlet opening 547 can be reduced. This makes it possible to reduce the possibility of foreign matter flowing into the liquid injection head 12.

The liquid intermediate flow path 86 connects the ascending flow path 83 and the descending flow path 84. The liquid intermediate flow path 86 is located at the highest portion of the liquid communication flow path 80 in the mounted state. That is, the liquid communication flow path 80 is a portion higher than the upstream end 82 and the downstream end 85 forming both ends of the liquid communication flow path 80 in the mounted state. The liquid intermediate flow path 86 is a flow path that changes the flow of the liquid from upward to downward, and is a flow path that is bent 180 degrees. Further, the liquid intermediate flow path 86 is arranged at a position lower than the highest portion (air second flow path 73) of the air communication flow path 70, which will be described later, in the mounted state.

The descending flow path 84 is located downstream of the ascending flow path 83 and the liquid intermediate flow path 86 in the flow direction, and extends downward in the mounted state. In the present embodiment, the descending flow path 84 extends vertically downward from the liquid intermediate flow path 86. In another embodiment, the descending flow path 84 may extend diagonally as long as it has a lower component.

The downstream end 85 is located downstream of the descending flow path 84 in the flow direction and is connected to the liquid supply unit 50. The downstream end 85 is formed as a connection chamber that connects the descending flow path 84 and the liquid inlet 809 as the upstream end of the liquid supply unit 50, which will be described later. This connection chamber also serves as a second connection end 75 of the air communication flow path 70, which will be described later.

The air communication flow path 70 (FIG. 8) forms a first connection end 72 forming one end, an air first flow path 76, an air second flow path 73, an air third flow path 74, and the other end. It has a second connection end 75 and the like. In the mounted state, the air communication flow path 70 is connected to the first liquid chamber 51 at a position higher than the upstream end 82, which is the connection position between the liquid communication flow path 80 and the first liquid chamber 51. Further, since the upper end of the liquid intermediate flow path 86 is arranged at a position higher than the uppermost portion 519 of the first liquid chamber 51, the liquid tank 30 accommodates the liquid up to the vicinity of the uppermost portion 519 of the first liquid chamber 51. can do.

The first connection end 72 is an opening formed in the uppermost portion 519 of the peripheral wall 518. That is, the air communication flow path 70 is connected to the uppermost portion 519 of the first liquid chamber 51 in the mounted state. The air first flow path 76 extends upward from the first connection end 72 in the mounted state. The air second flow path 73 connects the air first flow path 76 and the air third flow path 74, and extends in the horizontal direction (in the present embodiment, the X-axis direction) in the mounted state. The air third flow path 74 extends downward from the air second flow path 73 in the mounted state. In the air third flow path 74, the second connection end 75 is connected to the liquid supply unit 50. The second connection end 75 is formed as a connection chamber that connects the third air flow path 74 and the liquid inlet 809.

The liquid supply unit 50 (FIG. 7) is located below the downstream end 85 in the mounted state. Further, the liquid supply unit 50 extends downward toward the liquid supply port 505 in the mounted state. In the present embodiment, the liquid supply unit 50 extends vertically downward toward the liquid supply port 505 in the mounted state, but in other embodiments, the liquid supply unit 50 is oblique if it has a downward component. It may be extended.

The liquid supply unit 50 (FIG. 8) has a liquid inlet 809, a first supply unit 501, and a second supply unit 502. The liquid inlet 809 forms the upstream end of the liquid supply section 50 in the liquid flow direction. The liquid inlet 809 is open vertically upward in the mounted state. The first supply unit 501 forms a flow path connected to the liquid inlet 809 inside. The first supply unit 501 is formed in the tank body 40. The second supply unit 502 is connected to the first supply unit 501. The second supply unit 502 is formed by a member that projects vertically downward from the lower surface 402 in the mounted state. The second supply unit 502 has a liquid supply port 505. The liquid supply port 505 opens vertically downward in the mounted state.

As shown in FIG. 8, when the liquid tank 30 is viewed from one side (-Y-axis direction side) of the one side wall 408, the liquid injection portion 42 and the liquid supply port 505 are arranged at diagonal positions. There is. For example, when the liquid tank 30 is viewed from one side (-Y-axis direction side) of the one side wall 408, the liquid injection portion 42 is vertically above the first liquid chamber 51 and is the first in the mounted state. The liquid supply port 505 is located on one side (+ X-axis direction side) in the horizontal direction (for example, the X-axis direction) with respect to the liquid chamber 51, and the liquid supply port 505 is vertically downward with respect to the first liquid chamber 51 in the mounted state and is the first. 1 It is located on the other side (−X-axis direction side) in the horizontal direction (for example, the X-axis direction) from the liquid chamber 51. As a result, it is possible to prevent the distance from the liquid injection unit 42 to the liquid supply port 505 from becoming short, so that even if bubbles are generated when the liquid is injected from the liquid injection unit 42 into the second liquid chamber 52, the liquid is supplied. The possibility of air bubbles reaching the mouth 505 can be reduced. As a result, it is possible to reduce the number of air bubbles staying in the vicinity of the liquid supply port 505 in the liquid supply unit 50, so that the possibility of air bubbles flowing into the liquid injection head 12 can be reduced. Further, since the flow path through which the liquid flows from the liquid injection unit 42 to the liquid supply port 505 can be efficiently arranged, it is possible to suppress the increase in size of the liquid tank 30.

Next, the atmospheric communication unit 300 will be described with reference to FIGS. 9 and 10A. The "upstream side" and "downstream side" used in the description of the atmospheric communication unit 300 are based on the flow direction of the fluid (air) from the outside toward the second liquid chamber 52.

The atmospheric communication section 300 includes an atmospheric opening section 44 as an upstream end, a first atmospheric flow path 302 (FIG. 9), a second atmospheric flow path 304 (FIG. 9), and a meandering flow path 306 (FIG. 9) in order from the upstream side. 9), a gas-liquid separation chamber 308 (FIG. 9), a buffer chamber 310 (FIG. 10A), an atmospheric intermediate flow path 372 (FIG. 9), and an atmospheric introduction section 340 as a downstream end. Here, in the atmospheric communication portion 300, various flow paths formed on one side (-Y-axis direction side) of the one side wall 408 are partitioned by the tank body 40 and the first film 91 (FIG. 4). The various flow paths formed on the other side (+ Y-axis direction side) of the one side wall 408 are partitioned by the tank body 40 and the third film 93 (FIG. 4). The buffer chamber 310 includes a first buffer chamber 312, a second buffer chamber 314, a third buffer chamber 316, a fourth buffer chamber 318, and a fifth buffer chamber 319 in this order from the upstream side.

The atmosphere opening portion 44 (FIG. 9) is a tubular member extending in the + Z axis direction from the portion of the upper surface 401 on the back surface 403 side. The first air flow path 302 (FIG. 9) is a flow path connecting the air opening 44 and the second atmospheric flow path 304. The second air flow path 304 is an elongated flow path extending along the X-axis direction. The meandering flow path 306 is a flow path connecting the second atmospheric flow path 304 and the gas-liquid separation chamber 308. The meandering flow path 306 is an elongated meandering flow path in order to lengthen the flow path length of the atmospheric communication portion 300. As a result, it is possible to prevent the water in the liquid in the second liquid chamber 52 from evaporating. A gas-liquid separation membrane (not shown) is arranged on the inner peripheral wall 307 of the gas-liquid separation chamber 308. The gas-liquid separation membrane is made of a material that allows gas permeation and does not allow liquid permeation. The downstream end of the gas-liquid separation chamber 308 is a through hole 331 penetrating the one side wall 408. The gas-liquid separation chamber 308 and the first buffer chamber 312 (FIG. 10A) are connected by the through hole 331. The first buffer chamber 312 communicates with the second buffer chamber 314 via a gap 311 between the third film 93 and the + Y-axis direction end surface of the tank body 40.

The second buffer chamber 314 and the first intermediate connection flow path 341 (FIG. 8) communicate with each other by a through hole 332 penetrating the one side wall 408. The downstream end of the first intermediate connection flow path 341 is a through hole 333 penetrating the one side wall 408. The through hole 333 communicates the first intermediate connection flow path 341 with the third buffer chamber 316 (FIG. 10A). The third buffer chamber 316 and the second intermediate connection flow path 344 are communicated with each other by a through hole 334 penetrating the one side wall 408. The second intermediate connection flow path 344 and the fourth buffer chamber 318 communicate with each other by a through hole 335 penetrating the one side wall 408. The fourth buffer chamber 318 and the third intermediate connection flow path 371 are communicated with each other by a through hole 336 penetrating the one side wall 408. The third intermediate connection flow path 371 and the fifth buffer chamber 319 communicate with each other by a through hole 337 penetrating the one side wall 408 and a notch 338 formed around the through hole 337. The bottom surface 319a of the fifth buffer chamber 319 is inclined so as to be located downward from the notch 338 on the upstream side toward the through hole 339 on the downstream side. As a result, even if the liquid enters the fifth buffer chamber 319 through the through hole 339, the possibility that the liquid reaches the notch 338 can be reduced.

The fifth buffer chamber 319 and the atmospheric intermediate flow path 372 are communicated with each other by a through hole 339 penetrating the one side wall 408. The atmospheric intermediate flow path 372 and the second liquid chamber 52 communicate with each other by the atmospheric introduction portion 340 penetrating the one side wall 408. The atmosphere introduction unit 340 is arranged near the upper surface of the second liquid chamber 52 in the mounted state.

A-4. Initial filling of liquid tank 30:
The initial filling of the liquid into the liquid tank 30 will be described with reference to FIGS. 11 to 13. FIG. 11 is a first diagram for explaining the initial filling of the liquid. FIG. 12 is a second diagram for explaining the initial filling of the liquid. FIG. 13 is a third diagram for explaining the initial filling of the liquid. In FIGS. 11 to 13, dots are attached to the region where the liquid exists.

In the initial filling of the liquid, first, the liquid is injected into the second liquid chamber 52 (FIG. 6) from the liquid injection unit 42 (FIG. 5). Next, as shown by the arrow in FIG. 11, suction (discharge operation) of the fluid (for example, air or liquid) in the liquid tank 30 is started from the liquid injection head 12 via the liquid supply unit 50. This suction is performed by driving the suction pump 16 of the discharge unit 18 (FIG. 2). Due to this suction, the inside of the first liquid chamber 51 becomes negative pressure, so that the valve mechanism 60 is opened, and the liquid in the second liquid chamber 52 flows into the first liquid chamber 51 through the inlet opening 547. Here, since the flow of the liquid to the liquid supply unit 50 is blocked by the ascending flow path 83 of the liquid communication flow path 80, it is possible to prevent the liquid from flowing from the first liquid chamber 51 into the liquid supply unit 50. On the other hand, as the liquid flows into the first liquid chamber 51, the air in the first liquid chamber 51 is discharged to the liquid injection head 12 side through the air communication flow path 70 and the liquid supply unit 50. As a result, the water level of the first liquid chamber 51 rises.

As shown in FIG. 12, when the water level of the first liquid chamber 51 rises and reaches the same height as the uppermost part of the liquid communication flow path 80, the inflow of the liquid into the liquid communication flow path 80 is started. As shown by the arrow YT, the liquid flows from the liquid communication flow path 80 to the liquid supply unit 50 side. The inflow of the liquid from the liquid communication flow path 80 to the liquid supply unit 50 side is rapidly performed by the siphon phenomenon in addition to the suction from the suction pump 16.

As shown in FIG. 13, when the suction is further continued, the liquid flowing into the liquid communication flow path 80 flows into the air communication flow path 70 through the second connection end 75. Further, the liquid that has flowed into the liquid communication flow path 80 flows into the liquid supply unit 50 and the liquid injection head 12. When the liquid flows into the air communication flow path 70, the air existing in the air communication flow path 70 flows into the first liquid chamber 51. When the air existing in the air communication flow path 70 flows into the first liquid chamber 51, the water level in the first liquid chamber 51 is lowered. However, since the volume of the first liquid chamber 51 is sufficiently larger than the volume of the air communication flow path 70, it is possible to prevent the water level of the first liquid chamber 51 from dropping to the extent that the air reaches the upstream end 82. In other words, the upstream end 82 is one of the first liquid chambers 51 when the volume of the air communication flow path 70 flows into the first liquid chamber 51 from the state where the first liquid chamber 51 is filled with the liquid. It is connected to a position below the area where the inflowing air is located in the mounted state. In this way, after the liquid communication flow path 80 is filled with the liquid, it is possible to prevent the air in the first liquid chamber 51 from flowing into the liquid communication flow path 80 from the upstream end 82, so that the bubbles are liquid at the time of initial filling. The possibility of flowing into the injection head 12 can be reduced.

As described above, the initial filling of the liquid into the first liquid chamber 51, the liquid communication flow path 80, the liquid supply unit 50, and the liquid injection head 12 is completed. After the initial filling is completed, the suction by the suction pump 16 is stopped. The liquid in the first liquid chamber 51 when the initial filling is completed does not exist in the entire first liquid chamber 51, but air having a volume of about the air communication flow path 70 exists.

A-5. About the liquid tank 30 after the initial filling of the liquid:
The liquid tank 30 after the initial filling of the liquid will be described with reference to FIGS. 14 to 18. FIG. 14 is a first diagram for explaining the liquid tank 30 after the initial filling of the liquid. FIG. 15 is a second diagram for explaining the liquid tank 30 after the initial filling of the liquid. FIG. 16 is a third diagram for explaining the liquid tank 30 after the initial filling of the liquid. FIG. 17 is a fourth diagram for explaining the liquid tank 30 after the initial filling of the liquid. FIG. 18 is a fifth diagram for explaining the liquid tank 30 after the initial filling of the liquid. In FIGS. 14 to 18, dots are attached to the regions where the liquid exists.

As shown in FIG. 14, in the liquid tank 30 after the initial filling of the liquid, as time elapses, air passes through the tank body 40 and the first film 91 (FIG. 4) and air enters the first liquid chamber 51 from the outside. Gradually invade. As a result, the bubbles in the first liquid chamber 51 grow and become larger, and the water level in the first liquid chamber 51 drops. However, when not much time has passed since the initial filling, the amount of air flowing into the first liquid chamber 51 from the outside is small, so that the water level of the first liquid chamber 51 is located above the upstream end 82. Is maintained. In this state, the inflow of air bubbles into the liquid injection head 12 through the ascending flow path 83 can be suppressed, so that the occurrence of nozzle omission, which is a phenomenon in which the liquid is not injected from the liquid injection head 12, can be suppressed.

As shown in FIG. 15, when more time elapses, more air invades the first liquid chamber 51 from the outside, and bubbles in the first liquid chamber 51 grow, the water level in the first liquid chamber 51 rises upstream. Below the top edge of the end 82. In this case, since the upstream end 82 is in contact with the air existing in the first liquid chamber 51, the air in the first liquid chamber 51 can flow into the liquid communication flow path 80. When the air in the first liquid chamber 51 flows into the liquid communication flow path 80, the liquid in the liquid communication flow path 80 (first liquid) and the liquid in the second liquid chamber 51 (second liquid) are continuous. The first liquid and the second liquid are separated by air without being connected to.

When the liquid is injected from the liquid injection head 12 and the recording operation (printing operation) is executed in the state of FIG. 15, the phenomenon described below occurs. That is, as shown in FIG. 16, the liquid in the liquid communication flow path 80 is consumed, and as shown by the arrow YP, the air in the first liquid chamber 51 moves to the liquid supply unit 50 side via the air communication flow path 70. Inflow. Further, when the recording operation is executed, as shown in FIG. 17, the liquid in the liquid supply unit 50 is consumed and air flows into the liquid injection head 12 side, which may cause missing dots.

As shown in FIG. 17, when air flows into the liquid injection head 12 side and missing dots occur, the user operates the operation unit 4 (FIG. 1) to cause the discharge unit 18 to execute the discharge operation. As a result, the liquid is filled in the liquid communication flow path 80, the liquid supply unit 50, and the liquid injection head 12 as shown in FIG. 18 through the same process as the initial filling of the liquid (FIGS. 12 to 13). When the amount of liquid in the second liquid chamber 52 becomes small, the user injects the liquid from the liquid injection unit 42 (FIG. 4) into the second liquid chamber 52. Here, when a liquid flows in the liquid communication flow path 80 due to the recording operation (printing operation) of the liquid injection head 12 or the discharge operation by the discharge unit 18, the liquid communication is performed by the pressure loss of the liquid communication flow path 80. The pressure on the downstream side of the flow path 80 decreases. However, since the degree of pressure decrease is very small, the water level on the second connection end 75 side of the air communication flow path 70 hardly decreases. Therefore, the possibility that air bubbles flow into the liquid supply unit 50 from the air communication flow path 70 is reduced.

The liquid injection head 12 is newly provided with a sensor for detecting that air has flowed into the liquid injection head 12 from the liquid tank 30, and when the sensor detects the inflow of air, the liquid injection device 1 discharges the liquid. You may notify the user to prompt the execution of. This notification may be performed, for example, by providing a new display unit on the front surface 103 (FIG. 1) and displaying a message prompting the execution of the discharge operation on the display unit.

According to the above embodiment, the liquid supply unit 50 is located below the downstream end 85 in the mounted state and extends downward toward the liquid supply port 505 (FIG. 8). As a result, it is possible to prevent the liquid tank 30 from becoming large in the horizontal direction. Further, as a result, the liquid can be smoothly circulated from the liquid supply unit 50 to the liquid injection head 12, so that the liquid can be efficiently supplied to the liquid injection head 12.

Further, according to the above embodiment, when the liquid injection head 12 or the like is filled with the liquid by sucking the inside of the liquid tank 30 from the liquid injection head 12 side, the liquid is pushed out by the liquid flowing into the air communication flow path 70. The air can be released to the first liquid chamber 51 via the air communication flow path 70. Therefore, it is possible to reduce the possibility that air bubbles flow into the liquid injection head when the liquid injection head 12 is filled with the liquid. Further, according to the above embodiment, the valve mechanism 60 is opened when the liquid in the first liquid chamber 51 is sucked from the liquid injection head 12 and becomes a negative pressure, so that suction from the liquid injection head 12 is performed. The valve mechanism 60 is closed when the liquid is injected from the unfilled liquid injection section 42 into the second liquid chamber 52. Therefore, it is possible to prevent air bubbles in the second liquid chamber 52 generated when the liquid is injected from the liquid injection unit 42 into the second liquid chamber 52 from flowing into the first liquid chamber 51.

Further, according to the above embodiment, since the volume of the first liquid chamber 51 is smaller than that of the second liquid chamber 52, when the air of the first liquid chamber 51 is sucked and discharged to the liquid injection head 12, the air is sucked. The amount can be reduced. As a result, the air suction time can be shortened. Further, according to the above embodiment, the air communication flow path 70 is connected to the uppermost portion 519 of the first liquid chamber 51 in the mounted state (FIG. 8). This makes it possible to reduce the possibility of liquid flowing into the air communication flow path 70. Further, at the time of initial filling or during the discharge operation using the discharge unit 18 after the initial filling, the air on the liquid supply unit 50 side is smoothly flowed into the first liquid chamber 51 through the air communication flow path 70. Can be done.

B. Modification example:
The present invention is not limited to the above-mentioned examples and embodiments, and can be carried out in various embodiments without departing from the gist thereof. For example, the following modifications can be made.

B-1. First modification example:
The present invention is not limited to an inkjet printer and a liquid tank for supplying ink to an inkjet printer, but also to an arbitrary liquid injection device for injecting a liquid other than ink and a liquid tank for accommodating the liquid. Can be applied. For example, it can be applied to the following various liquid injection devices and their liquid tanks.
(1) Image recording device such as facsimile device (2) Color material injection device used for manufacturing color filter for image display device such as liquid crystal display (3) Organic EL (Electro Luminescence) display and surface emission display (Field) Electrode material injection device used for electrode formation such as Emission Display, FED) (4) Liquid injection device for injecting liquid containing bioorganic substances used for biochip production (5) Sample injection device as a precision pipette (6) Lubrication Oil injection device (7) Resin liquid injection device (8) Liquid injection device that injects lubricating oil pinpointly into precision machinery such as watches and cameras (9) Micro hemispherical lenses (optical lenses) used for optical communication elements, etc. ) Etc., a liquid injection device that injects a transparent resin liquid such as an ultraviolet curable resin liquid onto a substrate (10) A liquid injection device that injects an acidic or alkaline etching solution to etch a substrate or the like (11) A liquid injection device including a liquid injection head that ejects any other minute amount of droplets.

The term "droplet" refers to the state of the liquid discharged from the liquid injection device, and includes those having a granular, tear-like, or thread-like tail. Further, the term "liquid" as used herein may be any material that can be injected by the liquid injection device. For example, the "liquid" may be a material in a liquid state when the substance is in a liquid phase, a material in a liquid state having high or low viscosity, and a sol, gel water, other inorganic solvent, organic solvent, solution, etc. Liquid materials such as liquid resins and liquid metals (metal melts) are also included in "liquid". Further, not only a liquid as a state of a substance, but also a liquid in which particles of a functional material made of a solid substance such as a pigment or a metal particle are dissolved, dispersed or mixed in a solvent is included in the "liquid". Further, as a typical example of the liquid, ink, liquid crystal and the like as described in the above-described embodiment can be mentioned. Here, the ink includes general water-based inks, oil-based inks, and various liquid compositions such as gel inks and hot melt inks.

The present invention is not limited to the above-described embodiments, examples, and modifications, and can be realized with various configurations within a range not deviating from the gist thereof. For example, the technical features in the embodiments, examples, and modifications corresponding to the technical features in each embodiment described in the column of the outline of the invention may be used to solve some or all of the above-mentioned problems. , It is possible to replace or combine as appropriate in order to achieve a part or all of the above-mentioned effects. Further, if the technical feature is not described as essential in the present specification, it can be deleted as appropriate.

1 ... Liquid injection device, 2 ... Front cover, 3 ... Discharge port, 4 ... Operation unit, 6 ... Top cover, 11 ... Mounting part, 11a ... Mounting part side window, 12 ... Liquid injection head, 13 ... Guide rail, 14 ... Cap, 15 ... Suction tube, 16 ... Suction pump, 17 ... Control unit, 18 ... Discharge unit, 19 ... Carriage, 20 ... Recording medium, 30 ... Liquid tank, 40 ... Tank body, 42 ... Liquid injection unit, 44 ... air opening part, 45 ... partition wall, 46 ... flow path wall, 48 ... corner part, 49 ... bottom surface, 50 ... liquid supply part, 51 ... first liquid chamber, 52 ... second liquid chamber, 54 ... connection flow path , 59 ... lever, 60 ... valve mechanism, 62 ... first urging member, 64 ... valve body, 65 ... second urging member, 66 ... seal member, 67 ... rod, 68 ... pressure receiving plate, 70 ... air communication Road, 72 ... 1st connection end, 73 ... Air 2nd flow path, 74 ... Air 3rd flow path, 75 ... 2nd connection end, 76 ... Air 1st flow path, 80 ... Liquid communication flow path, 82 ... Upstream Edge, 83 ... ascending flow path, 84 ... descending flow path, 85 ... downstream end, 86 ... liquid intermediate flow path, 91 ... first film, 92 ... second film, 93 ... third film, 100 ... outer shell, 101 ... top surface, 102 ... bottom surface, 103 ... front surface, 103a ... device side window, 104 ... back surface, 105 ... right side surface, 106 ... left side surface, 122 ... liquid introduction needle part, 200 ... supply unit valve mechanism, 202 ... valve seat , 203 ... Valve body, 204 ... Spring, 300 ... Atmospheric communication part, 302 ... First atmospheric flow path, 304 ... Second atmospheric flow path, 306 ... Serpentine flow path, 307 ... Inner peripheral wall, 308 ... Gas-liquid separation chamber, 310 ... Buffer room, 311 ... Gap, 312 ... 1st buffer room, 314 ... 2nd buffer room, 316 ... 3rd buffer room, 318 ... 4th buffer room, 319 ... 5th buffer room, 319a ... Bottom surface, 331 ... Through hole, 332 ... Through hole, 333 ... Through hole, 334 ... Through hole, 335 ... Through hole, 336 ... Through hole, 337 ... Through hole, 338 ... Notch, 339 ... Through hole, 340 ... Atmospheric introduction part, 341 ... 1st intermediate connection flow path, 344 ... 2nd intermediate connection flow path, 371 ... 3rd intermediate connection flow path, 372 ... Atmospheric intermediate flow path, 401 ... Top surface, 402 ... Bottom surface, 403 ... Back surface, 404 ... Front surface, 404fa ... second liquid chamber bottom surface, 405 ... left side surface, 406 ... right side surface, 408 ... one side wall, 466 ... end surface, 501 ... first supply unit, 502 ... second supply unit, 505 ... liquid supply port, 515 ... side wall, 517 ... Bottom wall, 518 ... Peripheral wall, 519 ... Top, 541 ... Filter member, 542 ... Filter chamber, 542A ... First part, 542B ... Second part, 543 ... Arrangement part, 544 ... Intermediate flow path, 545 ... Communication opening, 546 ... Valve arrangement chamber, 547 ... Inlet opening, 548 ... Inflow opening, 549 ... Frame-shaped member, 809 ... Liquid inlet

Claims (7)

A liquid tank that is detachably mounted on a carriage equipped with a liquid injection head.
A liquid supply unit having a liquid supply port for receiving the liquid introduction needle portion of the liquid injection head and to which the liquid introduction needle portion is detachably connected.
A first liquid chamber capable of accommodating the liquid to be supplied to the liquid supply unit, and
A liquid communication flow path that connects the first liquid chamber and the liquid supply unit and can supply the liquid in the first liquid chamber to the liquid supply unit, and the liquid tank is mounted on the carriage. A liquid communication flow path that forms a convex flow path on the upper side in the mounted state,
An air communication flow path that connects the first liquid chamber and the liquid supply unit and allows air to flow between the first liquid chamber and the liquid supply unit, and is a liquid communication flow path in the mounted state. An air communication flow path connected to the first liquid chamber at a position higher than the connection position between the path and the first liquid chamber is provided.
The liquid communication flow path is in the flow direction of the liquid from the liquid tank to the liquid injection head.
The upstream end connected to the first liquid chamber and
An ascending flow path located on the downstream side of the upstream end and extending upward in the mounted state,
A descending flow path located downstream of the ascending flow path and extending downward in the mounted state,
It has a downstream end located on the downstream side of the descending flow path and connected to the liquid supply unit.
In the mounted state, the liquid supply unit is located below the downstream end and extends downward toward the liquid supply port .
The liquid tank further
A second liquid chamber capable of accommodating the liquid to be supplied to the first liquid chamber, and
A connection flow path that connects the first liquid chamber and the second liquid chamber and can supply the liquid in the second liquid chamber to the first liquid chamber.
A liquid injection unit capable of injecting the liquid into the second liquid chamber,
It has an atmospheric communication unit that communicates the second liquid chamber with the atmosphere.
The connecting flow path has an inlet opening that forms one end and is connected to the first liquid chamber.
The liquid tank further has a valve mechanism that opens and closes the inlet opening to control the inflow of the liquid from the second liquid chamber to the first liquid chamber.
The inlet opening is a liquid tank that is arranged at a position lower than the upstream end in the mounted state. The liquid tank according to claim 1.
The valve mechanism is a liquid tank that opens when at least the first liquid chamber becomes negative pressure. A liquid tank that is detachably mounted on a carriage equipped with a liquid injection head.
A liquid supply unit having a liquid supply port for receiving the liquid introduction needle portion of the liquid injection head and to which the liquid introduction needle portion is detachably connected.
A first liquid chamber capable of accommodating the liquid to be supplied to the liquid supply unit, and
A liquid communication flow path that connects the first liquid chamber and the liquid supply unit and can supply the liquid in the first liquid chamber to the liquid supply unit, and the liquid tank is mounted on the carriage. A liquid communication flow path that forms a convex flow path on the upper side in the mounted state,
An air communication flow path that connects the first liquid chamber and the liquid supply unit and allows air to flow between the first liquid chamber and the liquid supply unit, and is a liquid communication flow path in the mounted state. An air communication flow path connected to the first liquid chamber at a position higher than the connection position between the path and the first liquid chamber is provided.
The liquid communication flow path is in the flow direction of the liquid from the liquid tank to the liquid injection head.
The upstream end connected to the first liquid chamber and
An ascending flow path located on the downstream side of the upstream end and extending upward in the mounted state,
A descending flow path located downstream of the ascending flow path and extending downward in the mounted state,
It has a downstream end located on the downstream side of the descending flow path and connected to the liquid supply unit.
In the mounted state, the liquid supply unit is located below the downstream end and extends downward toward the liquid supply port.
The liquid tank further
A second liquid chamber capable of accommodating the liquid to be supplied to the first liquid chamber, and
A connecting flow path that connects the first liquid chamber and the second liquid chamber and can supply the liquid in the second liquid chamber to the first liquid chamber.
A liquid injection unit capable of injecting the liquid into the second liquid chamber,
It has an atmospheric communication unit that communicates the second liquid chamber with the atmosphere.
The first liquid chamber is a liquid tank having a smaller volume than the second liquid chamber. A liquid tank that is detachably mounted on a carriage equipped with a liquid injection head.
A liquid supply unit having a liquid supply port for receiving the liquid introduction needle portion of the liquid injection head and to which the liquid introduction needle portion is detachably connected.
A first liquid chamber capable of accommodating the liquid to be supplied to the liquid supply unit, and
A liquid communication flow path that connects the first liquid chamber and the liquid supply unit and can supply the liquid in the first liquid chamber to the liquid supply unit, and the liquid tank is mounted on the carriage. A liquid communication flow path that forms a convex flow path on the upper side in the mounted state,
An air communication flow path that connects the first liquid chamber and the liquid supply unit and allows air to flow between the first liquid chamber and the liquid supply unit, and is a liquid communication flow path in the mounted state. An air communication flow path connected to the first liquid chamber at a position higher than the connection position between the path and the first liquid chamber is provided.
The liquid communication flow path is in the flow direction of the liquid from the liquid tank to the liquid injection head.
The upstream end connected to the first liquid chamber and
An ascending flow path located on the downstream side of the upstream end and extending upward in the mounted state,
A descending flow path located downstream of the ascending flow path and extending downward in the mounted state,
It has a downstream end located on the downstream side of the descending flow path and connected to the liquid supply unit.
In the mounted state, the liquid supply unit is located below the downstream end and extends downward toward the liquid supply port.
The liquid tank further
A second liquid chamber capable of accommodating the liquid to be supplied to the first liquid chamber, and
A connecting flow path that connects the first liquid chamber and the second liquid chamber and can supply the liquid in the second liquid chamber to the first liquid chamber.
A liquid injection unit capable of injecting the liquid into the second liquid chamber,
It has an atmospheric communication unit that communicates the second liquid chamber with the atmosphere.
The liquid tank further
Has a tank body with one side wall,
The first liquid chamber, the liquid communication flow path, and the air communication flow path are formed on one side of the one side wall.
The second liquid chamber is a liquid tank formed on the other side opposite to one side of the one side wall. The liquid tank according to claim 4.
A liquid tank in which the liquid injection portion and the liquid supply port are arranged at diagonal positions when the liquid tank is viewed from one side of the one side wall. A liquid tank that is detachably mounted on a carriage equipped with a liquid injection head.
A liquid supply unit having a liquid supply port for receiving the liquid introduction needle portion of the liquid injection head and to which the liquid introduction needle portion is detachably connected.
A first liquid chamber capable of accommodating the liquid to be supplied to the liquid supply unit, and
A liquid communication flow path that connects the first liquid chamber and the liquid supply unit and can supply the liquid in the first liquid chamber to the liquid supply unit, and the liquid tank is mounted on the carriage. A liquid communication flow path that forms a convex flow path on the upper side in the mounted state,
An air communication flow path that connects the first liquid chamber and the liquid supply unit and allows air to flow between the first liquid chamber and the liquid supply unit, and is a liquid communication flow path in the mounted state. An air communication flow path connected to the first liquid chamber at a position higher than the connection position between the path and the first liquid chamber is provided.
The liquid communication flow path is in the flow direction of the liquid from the liquid tank to the liquid injection head.
The upstream end connected to the first liquid chamber and
An ascending flow path located on the downstream side of the upstream end and extending upward in the mounted state,
A descending flow path located downstream of the ascending flow path and extending downward in the mounted state,
It has a downstream end located on the downstream side of the descending flow path and connected to the liquid supply unit.
In the mounted state, the liquid supply unit is located below the downstream end and extends downward toward the liquid supply port.
The liquid tank further
A second liquid chamber capable of accommodating the liquid to be supplied to the first liquid chamber, and
A connecting flow path that connects the first liquid chamber and the second liquid chamber and can supply the liquid in the second liquid chamber to the first liquid chamber.
A liquid injection unit capable of injecting the liquid into the second liquid chamber,
It has an atmospheric communication unit that communicates the second liquid chamber with the atmosphere.
The connection flow path is connected to the second liquid chamber and has a filter chamber located below the second liquid chamber in the mounted state.
The filter chamber is in the mounted state.
The inflow opening connected to the second liquid chamber and
A filter member that divides the filter chamber into a first portion located on the upper side including the inflow opening and a second portion located on the lower side of the first portion, and is located below the inflow opening. A liquid tank having a filter member and a filter member. The liquid tank according to any one of claims 1 to 6.
The air communication flow path is a liquid tank connected to the uppermost portion of the first liquid chamber in the mounted state.

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