Printing apparatus, control method, storage medium, and program

Abstract

To reduce variation in supply pressure of liquid.SOLUTION: A recording apparatus comprising: a forming unit configured to form a liquid chamber configured to contain a liquid and a pressure chamber adjacent to the liquid chamber; a wall configured to separate the liquid chamber and the pressure chamber from each other and to be displaced in accordance with a pressure in the pressure chamber to change a volume of the liquid chamber; a regulating unit configured to regulate displacement of the wall in accordance with the pressure in the pressure chamber; and a pressure adjusting unit configured to adjust the pressure in the pressure chamber, the wall is displaced to increase a volume of the liquid chamber when the pressure chamber is in a negative pressure state, the regulation unit regulates a displacement range of the wall when the pressure chamber is in the negative pressure state and releases the regulation of the displacement range when the negative pressure state of the pressure chamber is released, and the pressure adjustment unit performs a replenishment operation of adjusting the pressure chamber to be in the negative pressure state and introducing the liquid into the liquid chamber and a supply operation of adjusting the pressure chamber to be in a positive pressure state and supplying the liquid from the liquid chamber to the ejection unit.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The present invention relates to a recording device. [Background technology]

[0002] To achieve stable ink ejection performance, a recording device has been proposed that supplies pressurized ink to an ejection head. Patent Document 1 discloses a device that has a flow path unit that supplies pressurized ink between a container that stores ink and the liquid ejection head. The flow path unit increases or decreases the volume of a liquid feed chamber to introduce ink from the container to the liquid feed chamber and to feed ink from the liquid feed chamber to the liquid ejection head. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2010-023424 Summary of the Invention [Problem to be solved by the invention]

[0004] In a configuration in which the volume of the liquid chamber increases or decreases, as in Patent Document 1, if the volume of the liquid chamber increases more than expected when ink is introduced, the restoring force of the components of the liquid chamber may act when the ink is supplied to the ejection head, causing the ink supply pressure to become higher than expected.

[0005] The present invention provides a technique for reducing variations in supply pressure when supplying liquid. [Means for solving the problem]

[0006] According to the present invention, a liquid chamber for receiving liquid from a liquid container and for storing the liquid to be supplied to a discharge means for discharging the liquid onto a recording medium, and a forming means for forming a pressure chamber adjacent to the liquid chamber; a wall that separates the liquid chamber from the pressure chamber and that changes the volume of the liquid chamber by being displaced in response to the pressure of the pressure chamber; a restricting means provided in the pressure chamber for restricting displacement of the wall body in accordance with the pressure of the pressure chamber; a pressure adjusting means for adjusting the pressure in the pressure chamber; the wall body is displaced so as to increase the volume of the liquid chamber when the pressure chamber is in a negative pressure state; the restricting means restricts the displacement range of the wall body when the pressure chamber is in a negative pressure state, and releases the restriction on the displacement range when the negative pressure state of the pressure chamber is released, The pressure adjusting means is a replenishing operation of adjusting the pressure chamber to a negative pressure state and introducing liquid from the liquid container into the liquid chamber; a supply operation of adjusting the pressure chamber to a positive pressure state and supplying liquid from the liquid chamber to the discharge means; A recording device is provided. [Effects of the Invention]

[0007] According to the present invention, it is possible to provide a technique for reducing variations in supply pressure when supplying liquid. [Brief explanation of the drawings]

[0008] [Figure 1] 1A is an external view of a recording apparatus according to an embodiment of the present invention, and FIG. 1B is a view showing the state in which the access cover is open. [Figure 2] FIG. 2 is an explanatory diagram of the internal mechanism of the recording device of FIG. [Figure 3] FIG. 4 is an explanatory diagram of a liquid supply unit from a container to a discharge head. [Figure 4] FIG. 4 is an explanatory diagram showing the structure of an intermediate tank. [Figure 5] FIG. [Figure 6] FIG. [Figure 7] FIG. 10 is an explanatory diagram of the remaining amount detection operation in the intermediate tank. [Figure 8]FIG. 10 is an explanatory diagram of remaining amount determination for an intermediate tank. [Figure 9] FIG. 4 is an explanatory diagram showing the structure of each check valve on the upstream and downstream sides of the intermediate tank. [Figure 10] 5A and 5B are explanatory diagrams of the structure and operation of a negative pressure maintaining unit. [Figure 11] FIG. [Figure 12] FIG. 4 is a diagram showing the opening and closing patterns of each control valve of the pressure adjustment unit. [Figure 13] FIG. 4 is an explanatory diagram of the operation of each control valve of the pressure adjustment unit. [Figure 14] 3A and 3B are diagrams showing a specific structural example of a pressure adjustment unit. [Figure 15] FIG. 3 is an explanatory diagram of the structure of a valve unit. [Figure 16] FIG. [Figure 17] FIG. 4 is a block diagram of a control circuit of the supply unit of FIG. 3; [Figure 18] 10 is a flowchart showing an example of processing by a control circuit. [Figure 19] 10 is a flowchart showing an example of processing by a control circuit. [Figure 20] 10 is a flowchart showing an example of processing by a control circuit. [Figure 21] 10 is a flowchart showing an example of processing by a control circuit. [Figure 22] 10 is a flowchart showing an example of processing by a control circuit. [Figure 23] FIG. 10 is an explanatory diagram showing an example in which a plurality of intermediate tanks are integrated together. [Figure 24] 10A and 10B are diagrams showing another example of the configuration of the restriction unit. [Figure 25] FIG. 10 is a diagram showing another example of the configuration of the remaining amount detection sensor. [Figure 26] FIG. 10 is an explanatory diagram of remaining amount determination for an intermediate tank. [Figure 27] 10 is a flowchart showing an example of processing by a control circuit. [Figure 28] FIG. [Figure 29] FIG. 29 is a perspective view showing the internal structure of the intermediate tank unit of FIG. 28. [Figure 30] Cross section of line AA in Figure 28. [Figure 31] 29 is a bottom view showing the internal structure of the intermediate tank unit of FIG. 28. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. Note that the following embodiments do not limit the scope of the invention claimed. Although multiple features are described in the embodiments, not all of these multiple features are necessarily essential to the invention, and multiple features may be combined arbitrarily. Furthermore, in the accompanying drawings, the same reference numerals are used to designate the same or similar components, and redundant explanations will be omitted.

[0010] First Embodiment <Outline of the recording device> FIG. 1(A) is an external view of a recording apparatus 1 according to one embodiment of the present invention, as seen from the front. The recording apparatus 1 of this embodiment is an inkjet recording apparatus that ejects ink as a liquid to perform recording on a recording medium. In the figure, arrows X to Z indicate directions that intersect with each other, and in this embodiment in particular, arrows X and Y indicate horizontal directions that are perpendicular to each other, and arrow Z indicates the up-down direction (direction of gravity). The X direction is the width direction (left-right direction) of the recording apparatus 1. The Y direction is the depth direction of the recording apparatus 1.

[0011] "Recording" not only includes the formation of meaningful information such as characters and figures, but also includes the formation of images, patterns, designs, etc. on a recording medium, whether meaningful or insignificant, or the processing of the medium, regardless of whether it is manifested in a way that can be perceived visually by humans. In addition, although sheet-like paper is assumed as the "recording medium" in this embodiment, it may also be cloth, plastic film, etc.

[0012] The recording device 1 has an overall rectangular parallelepiped shape, with a foldable paper feed tray 2A provided at the rear of its top surface, and a paper feed cassette 2B and an outlet 3 provided at its front. The paper feed tray 2A and paper feed cassette 2B form a loading section where recording media are stacked before recording. The paper feed cassette 2B can be inserted into and removed from the device body in the Y direction. After recording, the recording media are discharged from the outlet 3. The outlet 3 is provided with an outlet tray on which the recording media are placed after recording.

[0013] An operation unit 14 that can be operated by the user is provided on the front of the recording device 1. The operation unit 14 is provided with a display unit that displays information and a plurality of operation buttons, and can receive instructions input by the user and present information to the user. The display unit may be a touch panel.

[0014] Storage units 15A and 15B are provided at the front of the recording device 1. The storage units 15A and 15B are spaced apart in the X direction, and a paper feed cassette 2B and an outlet 3 are provided between the storage units 15A and 15B. The storage units 15A and 15B are provided with access covers 16A and 16B that open and close the storage units 15A and 15B, respectively. When the access covers 16A and 16B are opened, the interiors of the storage units 15A and 15B are exposed.

[0015] FIG. 1(B) shows the state in which access cover 16A is open. Storage section 15A stores multiple containers 17, and containers 17 are exposed when access cover 16A is opened. Containers 17 are liquid containers that store ink as a liquid. Containers 17 may be in the form of a rigid resin box or a flexible bag (pack). When access cover 16A is closed, containers 17 are covered by access cover 16A.

[0016] Each container 17 constitutes a cartridge-type ink tank that can be inserted and removed in the Y direction. The user can replace a container 17 by opening the access cover 16A. In this embodiment, three containers 17 are stored in the storage section 15A. The three containers 17 contain different types of ink. For example, the three containers 17 contain yellow, magenta, and cyan inks.

[0017] Storage section 15B and access cover 16B are similar to storage section 15A and access cover 16B. However, in the present embodiment, storage section 15B stores one container 17 (not shown). The container 17 stored in storage section 15B stores, for example, black ink. In the present embodiment, a configuration in which storage sections are provided on the left and right sides has been shown, but a configuration in which four color containers 17 are provided on one side, for example, at the position of storage section 15A, may also be used.

[0018] 2 is an explanatory diagram showing the internal mechanism of the recording device 1. The recording medium P set in the paper feed tray 2A or paper feed cassette 2B is conveyed by the conveyance unit 4A or 4B and the conveyance units 5 to 8, guided by the guide member 9. During the conveyance process, an image is recorded by the ejection head 11, and the recording medium is discharged to the discharge port 3. The guide member 9 has a guide portion 9a that forms a path for turning the recording medium P over, and the recording device 1 is also capable of double-sided recording on the recording medium P.

[0019] Of the transport units 4A and 4B and the transport units 5 to 8, the transport units 4A and 4B are arranged on the most upstream side in the transport direction of the recording medium P. The transport unit 5 is arranged downstream of the transport unit 4B, and the transport unit 6 is arranged downstream of the transport units 4A and 5. The transport unit 7 is arranged downstream of the transport unit 6, and the transport unit 8 is arranged downstream of the transport unit 7.

[0020] The transport unit 7 transports the recording medium P in the Y direction (sub-scanning direction) relative to the ejection head 11. The image recording position in the Y direction relative to the recording medium P is controlled by driving control of the transport unit 7. The transport unit 7 includes a drive roller 7a and a driven roller 7b that is in pressure contact with the drive roller 7a, and these rollers sandwich and transport the recording medium P.

[0021] The transport units 4A and 4B and the transport units 5 and 6 can also be called feeding units in that they feed the recording medium P to the transport unit 7. The transport units 4A and 4B in this embodiment are equipped with pickup rollers that pick up the recording medium P from the corresponding paper feed tray 2A or paper feed cassette 2B and transport it to the transport unit 5 or 6.

[0022] The transport units 5 and 6 include drive rollers 5a and 6a and driven rollers 5b and 6b that are in pressure contact with the corresponding drive rollers 5a and 6a, and these rollers sandwich and transport the recording medium P. The transport units 5 and 6 can also be called intermediate units or intermediate rollers because they are located between the most upstream transport units 4A and 4B and the transport unit 7.

[0023] The transport unit 8 can also be called a discharge unit because it discharges the recorded recording medium P to the discharge port 3. The transport unit 8 includes a drive roller 8a and a driven roller 7b that is in pressure contact with the drive roller 8a, and these rollers sandwich and transport the recording medium P.

[0024] The ejection head 11 is a recording head that ejects ink to perform recording on a recording medium. The ejection head 11 is positioned between the transport unit 7 and the transport unit 8 in the transport direction of the recording medium P. The ejection head 11 is mounted on a carriage 12. The ejection port surface (bottom surface) of the ejection head 11 faces the platen 10, and ejects liquid from multiple nozzles formed on the ink ejection surface onto the recording medium P transported over the platen 10. A different ejection head 11 is provided for each type of liquid.

[0025] The carriage 12 is moved back and forth in a direction across the recording medium P (in this embodiment, the X direction, the main scanning direction) by a drive unit 13. The drive unit 13 is a belt transmission mechanism driven by a motor, and includes, for example, a drive pulley and a driven pulley spaced apart in the X direction, an endless belt wound around these pulleys, and a guide member that guides the movement of the carriage 12 in the X direction. The carriage 12 is connected to the endless belt. When the drive pulley is rotated by the motor, the endless belt runs and the carriage 12 moves. The ejection head 11 may be replaceably attached to the carriage 12.

[0026] As described above, the recording device 1 of this embodiment is a serial type recording device in which the ejection head 11 is mounted on the carriage 12. The recording operation on the recording medium P is performed by the transport unit 7 by alternately repeating a transport operation (intermittent transport operation) that transports the recording medium P a predetermined amount and a recording scan while transport of the transport unit 7 is stopped. The recording scan is an operation in which ink is ejected from the ejection head 11 while the carriage 12 carrying the ejection head 11 is moved. Note that the ejection head 11 may be a full-line recording head extending in the X direction.

[0027] <Liquid supply system> Next, a description will be given of a supply unit for supplying liquid from the container 17 to the ejection head 11. FIG.

[0028] The supply unit 18 is a supply mechanism that supplies liquid from the container 17 to the ejection head 11. A supply unit 18 is provided for each container 17. Therefore, the recording apparatus 1 of this embodiment has four supply units 18. One of the four supply units 18 is shown in Figure 3.

[0029] The supply unit 18 includes an intermediate tank 20, check valves 30 and 40, a negative pressure maintenance unit 50, and a pressure adjustment unit 60. The intermediate tank 20 is connected to the container 17 via a pipe 19a, the check valve 30, and a pipe 19b. The negative pressure maintenance unit 50 is connected to the intermediate tank 20 via a pipe 19c, the check valve 40, and a pipe 19d.

[0030] The pressure adjustment unit 60 is connected to the intermediate tank 20 via a pipe 19e. The pipe 19e forms a flow path for a fluid for pressure control. In this embodiment, the fluid is a gas, particularly air. The pipe 19f forms an atmosphere communication path that communicates with the atmosphere. The pipes 19a to 19f are made of, for example, flexible tubes. The pipes 19a to 19d may be made of a material with low gas permeability or water vapor permeability so that the liquid flowing through them does not deteriorate. The pipes 19a to 19f do not necessarily have to be flexible tubes, and may use metal pipes for at least a portion thereof, or may form a flow path by tightly sealing a groove formed in a plate-shaped part with another part.

[0031] The liquid in the container 17 is introduced into the intermediate tank 20 via piping 19a, check valve 30, and piping 19b. In the direction of introducing the liquid, the container 17 is located upstream, and the intermediate tank 20 is located downstream. The check valve 30 is located upstream of the intermediate tank 20, and is a one-way valve (check valve) that prevents the liquid from flowing back from the intermediate tank 20 side to the container 17 side.

[0032] The liquid in the intermediate tank 20 is supplied to the discharge head 11 via the pipe 19c, the backflow prevention valve 40, the pipe 19d, and the negative pressure maintenance unit 50. In terms of the liquid supply direction, the intermediate tank 20 is located upstream, and the discharge head 11 is located downstream. The backflow prevention valve 40 is a one-way valve (check valve) that is provided downstream of the intermediate tank 20 and prevents the liquid from flowing back from the negative pressure maintenance unit 50 side to the intermediate tank 20 side.

[0033] In this embodiment, the supply of liquid from the container 17 to the intermediate tank 20 utilizes the pressure generated by the pressure adjustment unit 60, so the liquid pressure in the container 17 only needs to be close to atmospheric pressure, and there are few layout restrictions. Furthermore, because the supply of liquid to the discharge head 11 is performed using a pressurized system, there are few restrictions on the installation location of each component, and the intermediate tank 20 and the discharge head 11 may be installed in a location where there is a head difference between them.

[0034] (Intermediate tank) The configuration of the intermediate tank 20 will be described with reference to Figs. 3 and 4. Fig. 4 is an explanatory diagram showing the structure of the intermediate tank 20. The intermediate tank 20 performs an introduction operation of introducing the liquid contained in the container 17 by suction, and a supply operation of sending the introduced liquid toward the ejection head 11. The introduction operation can also be called a liquid replenishment operation. In terms of these two operations, the intermediate tank 20 plays the role of a pump.

[0035] The intermediate tank 20 includes a forming unit 21 that forms the liquid chamber 20a and the pressure chamber 20b. The forming unit 21 is a hollow body that forms an outer wall that defines the liquid chamber 20a and the pressure chamber 20b. In this embodiment, the forming unit 21 includes a cup-shaped housing 21A and a lid member 21B that closes an opening in the top of the housing 21A.

[0036] The liquid chamber 20a contains the liquid L to be supplied to the ejection head 11. The liquid L is introduced into the liquid chamber 20a from the container 17. The cover member 21B has an inlet pipe 21a that forms an inlet communicating with the liquid chamber 20a, and an outlet pipe 21b that forms an outlet communicating with the liquid chamber 20a. The inlet pipe 21a is connected to the pipe 19b, and the outlet pipe 21b is connected to the pipe 19c.

[0037] The pressure chamber 20b is formed adjacent to the liquid chamber 20a via a wall 22. The wall 22 separates the liquid chamber 20a from the pressure chamber 20b. The wall 22 can also be said to be part of the peripheral wall that defines the liquid chamber 20a and the pressure chamber 20b. The wall 22 is a diaphragm that changes the volume of the liquid chamber 20a by displacing in response to the pressure in the pressure chamber 20b. The wall 22 in this embodiment is made of a flexible sheet that elastically deforms in response to the pressure difference between the liquid chamber 20a and the pressure chamber 20b, and has a ring-shaped convex portion formed on its periphery.

[0038] Wall body 22 is airtightly sandwiched between cover member 21B and frame body 23. Frame body 23 is an annular member having an opening 23a in its center. Frame body 23 is supported by a plurality of shaft members 28 that are erected on the bottom of housing 21A. Wall body 22 is fixed by being sandwiched at its periphery between cover member 21B and frame body 23, and the center of wall body 22 is displaceable below opening 23a.

[0039] The housing 21A has a communication pipe 21c that forms a communication passage that communicates with the pressure adjustment unit 60 and the pressure chamber 20b. A pipe 19e is connected to the communication pipe 21c. The pressure chamber 20b is provided with a restriction unit 25 that restricts displacement of the wall body 22 in accordance with the pressure of the pressure chamber 20b. The restriction unit 25 restricts the maximum displacement position of the wall body 22 in the direction in which the liquid chamber 20a increases.

[0040] The restriction unit 25 includes a stopper 27 and a flexible member 26. The flexible member 26 forms a partition wall for the air chamber 20c in the pressure chamber 20b. In other words, the pressure chamber 20b is partitioned by the flexible member 26 into a portion of the air chamber 20c on the bottom side and a portion on the liquid chamber 20a side. The flexible member 26 is a diaphragm that changes the volume of the air chamber 20c by displacing in response to the pressure in the pressure chamber 20b. In this embodiment, the wall 22 is made of a flexible film that elastically deforms in response to the pressure difference between the liquid chamber 20a and the pressure chamber 20b, and its peripheral edge is airtightly fixed to the bottom of the housing 21A.

[0041] The housing 21A has a communication pipe 21d that forms an atmosphere communication port at its bottom. The communication pipe 21d is always open, and the air chamber 20c is maintained at atmospheric pressure. The stopper 27 has a hole (not shown) through which the shaft member 28 is inserted. The stopper 27 is a lifting member that is provided so as to be able to move up and down in the direction D1 (depth direction of the housing 21A) using the shaft member 28 as a guide axis and is displaced by displacement of the flexible member 26. In this embodiment, the flexible member 26 is disposed between the stopper 27 and the bottom of the housing 21A. When the pressure chamber 20b becomes negative pressure, the flexible member 26 displaces upward to increase the volume of the air chamber 20c, thereby causing the stopper 27 to rise to a restriction position that restricts the maximum displacement position. The stopper 27 has a recess 27a into which the abutment member 24 enters.

[0042] An abutment member 24 is fixed to the underside of the center of the wall body 22. The abutment member 24 displaces along with the displacement of the wall body 22. The abutment member 24 has an engagement groove 24a that engages with the end 70a of the detection lever 70. In this embodiment, the abutment member 24 abuts against a stopper 27, thereby restricting the displacement range of the wall body 22. A configuration in which the wall body 22 and the flexible member 26 are directly abutted against each other to restrict the displacement range of the wall body 22 can also be adopted. However, by interposing the abutment member 24 and the stopper 27, deterioration of the wall body 22 and the flexible member 26 can be prevented and the displacement range can be more accurately restricted.

[0043] A plurality of elastic members 29 are provided between the abutment member 24 and the stopper 27. In this embodiment, the elastic members 29 are coil springs through which the shaft member 28 is inserted, and urge the abutment member 24 and the stopper 27 in a direction separating them. In the state shown in FIG. 4, the abutment member 24 and the stopper 27 are separated, and the displacement range of the wall body 22 is not restricted.

[0044] The detection lever 70 is a movable member for detecting the remaining amount of liquid in the liquid chamber 20a. The detection lever 70 has its middle portion 70b passing through the axial hole 21e and is rotatably supported in the axial hole 21e. The center of the wall 22 and the abutment member 24 are displaced in the direction D1 depending on the remaining amount of liquid in the liquid chamber 20a. The detection lever 70 rotates in the direction D2 due to the displacement of the abutment member 24. In other words, the detection lever 70 rotates in conjunction with the displacement of the center of the wall 22. The amount of rotation of the detection lever 70 can be considered the amount of displacement of the wall 22 and the abutment member 24. The amount of rotation of the detection lever 70, i.e., the amount of displacement of the wall 22 and the abutment member 24, is detected by remaining amount detection sensors 71 and 72 located inside the housing 21A. The remaining amount of liquid in the liquid chamber 20a can be estimated based on the detection results of the remaining amount detection sensors 71 and 72. The detection lever 70 is constantly biased counterclockwise in Fig. 4 by an elastic member (not shown). The detection lever 70 may have a configuration in which its middle portion 70b passes through a shaft hole 21e formed in the housing 21A and extends to the outside of the housing 21A. In that case, the detection lever 70 may be configured to be rotatably supported in the airtightly sealed shaft hole 21e.

[0045] The operation of the intermediate tank 20 will be described with reference to Figures 5 and 6 in addition to Figure 4. Figures 5 and 6 show the operation of each part of the intermediate tank 20 together with the internal pressure state.

[0046] State ST51 in Figure 5 shows a state in which the liquid L in the liquid chamber 20a has been almost depleted by the supply operation, and the volume of the liquid chamber 20a is at its minimum. The pressure chamber 20b is in a positive pressure state by the pressure adjustment unit 60. The air chamber 20c has almost no volume, and the stopper 27 is located at a position closest to the bottom of the housing 21A. Conversely, the abutment member 24 is located at a position closest to the liquid chamber 20a. From this point, the refilling operation is performed. Note that it is not necessary to wait until the remaining amount in the liquid chamber 20a has decreased to the state ST51 before performing the refilling operation; for example, the refilling operation may be performed when the remaining amount is about 50%.

[0047] State ST52 in Figure 5 shows the stage at which the refilling operation has started and the pressure adjustment unit 60 has placed the pressure chamber 20b in a negative pressure state. By placing the pressure chamber 20b in a negative pressure state, the wall 22 and the abutment member 24 are displaced toward the bottom of the housing 21A. The volume of the liquid chamber 20a increases, and liquid L is sucked into the liquid chamber 20a from the container 17. In state ST52, approximately 50% of the maximum capacity of the liquid chamber 20a has been introduced into the liquid chamber 20a.

[0048] In state ST52 of FIG. 5, the flexible member 26 and stopper 27 are displaced in the opposite direction to the wall 22 (toward the cover member 21B), and air is sucked into the air chamber 20c, increasing its volume. In this embodiment, when the pressure chamber 20b is placed in a negative pressure state, the flexible member 26 is configured to displace before the wall 22. A viscous liquid flows into the liquid chamber 20a. On the other hand, air, which has a lower flow resistance than the liquid, flows into the air chamber 20c. The inner diameter and length of the communicating tube 21d can also be designed to have almost no flow resistance. In this way, the flexible member 26 can be quickly deformed. This allows the flexible member 26 to displace before the wall 22, i.e., the displacement range of the wall 22 can be restricted.

[0049] The stopper 27 moves parallel to the liquid chamber 20a by being guided by the multiple shaft members 28. The stopper 27 moves against the biasing force of the elastic member 29. The stopper 27 moves until it abuts against a protrusion (not shown) formed on the shaft members 28. This position becomes a restricting position that restricts the displacement range of the wall body 22. Note that the stopper 27 does not have to be configured to stop its movement at a predetermined position on the shaft members 28.

[0050] 5 shows a stage where liquid L has further flowed into liquid chamber 20a. Negative pressure remains in pressure chamber 20b, and wall 22 is displaced in a direction that increases the volume of liquid chamber 20a, causing it to swell and deform. Contact member 24 contacts stopper 27, restricting the displacement of wall 22.

[0051] If the projected areas of the wall 22 and the flexible member 26 on a horizontal plane (a plane perpendicular to the direction D1 in FIG. 4) are S1 and S2, then: S1 < S2 The shape is designed so that, under the same negative pressure NP, |NP|×S1 < |NP|×S2 The force tending to expand the flexible member 26 is stronger than the force tending to expand the wall body 22. Therefore, the abutment of the abutting member 24 with the stopper 27 reliably restricts the displacement of the wall body 22.

[0052] State ST61 in FIG. 6 shows a state in which negative pressure has continued to act on wall 22 since state ST53 in FIG. 5. Because stopper 27 restricts contact member 24 from moving further toward stopper 27, further elastic deformation occurs in a portion of wall 22 (a thin portion such as portion A in the figure). Then, when the force due to the negative pressure in pressure chamber 20b and the elastic deformation force of portion A of wall 22 are balanced, the deformation stops. A slight excess of liquid L flows into liquid chamber 20a by the amount of deformation of portion A. In other words, the volume of liquid chamber 20a in state ST61 is the maximum volume during a refilling operation, and this maximum volume is limited by restriction unit 25.

[0053] State ST62 in Figure 6 shows the state where the refilling operation has ended and the supply operation has begun. The pressure adjustment unit 60 releases the negative pressure in the pressure chamber 20b, and the pressure is changed to a positive pressure state via atmospheric pressure. Air is exhausted from the air chamber 20c through the communicating tube 21, and the flexible member 26 is displaced toward the communicating tube 21d in a collapsed manner. As the flexible member 26 is displaced, the stopper 27 is also displaced toward the communicating tube 21d by the bias of the elastic member 29, and the restriction on the displacement range of the wall body 22 is released.

[0054] When the restriction on the displacement range of wall body 22 is released, the constraint on portion A of wall body 22 shown in state ST61 is released, and wall body 22 attempts to restore its original shape. Because a small amount of excess liquid L corresponding to the deformation of portion A has already flowed into liquid chamber 20a, contact member 24 is displaced by that amount toward stopper 27. As a result, the pressure within liquid chamber 20a becomes approximately equal to the pressure within pressure chamber 20b, and when liquid L from liquid chamber 20a is pressurized and supplied toward ejection head 11, no elastic deformation force corresponding to the deformation of portion A of wall body 22 acts.

[0055] This point will be explained in more detail. Let us assume that, without the provision of the restriction unit 25, the wall 22 comes into contact with a portion (such as the inner wall of the pressure chamber 20b) where the displacement restriction cannot be released during the supply operation, causing a portion of the wall 22 to further elastically deform, as shown at portion A. In this state, if the pressure chamber 20b is changed from a negative pressure state to a positive pressure state, the pressure of the liquid L in the liquid chamber 20a will increase due to the restoring force of the portion of the wall 22, such as portion A, that has elastically deformed. As a result, the liquid L will be supplied with a force stronger than the pressure assumed by the control of the pressure adjustment unit 60, which may cause the flow of the liquid L on the ejection head 11 side to become unstable.

[0056] In contrast to this, in this embodiment, when pressure chamber 20b is in a negative pressure state, restriction unit 25 restricts displacement of wall 22, and when the negative pressure state is released, restriction on displacement of wall 22 is also released, and partial elastic deformation of wall 22 is eliminated. Therefore, it is possible to prevent the pressure of liquid L in liquid chamber 20a from increasing due to partial elastic deformation of wall 22. As a result, the supply pressure of liquid L supplied from liquid chamber 20a to the ejection head can be more accurately controlled by pressure adjustment unit 60, and variation in supply pressure can be reduced.

[0057] Incidentally, if this excessive elastic deformation of a portion of the wall 22 is detected and the negative pressure in the pressure chamber 20b is released before this occurs, excess liquid L can be prevented from flowing into the liquid chamber 20a. However, it is not easy to detect the stage immediately before excessive elastic deformation of a portion of the wall 22, and an additional sensor or the like is required. In contrast, this embodiment is advantageous in terms of cost and device layout.

[0058] At state ST62, the pressure state of pressure chamber 20b becomes positive, and the pressure of liquid L in liquid chamber 20a becomes substantially equal to the air pressure in pressure chamber 20b. State ST63 in Figure 6 shows a state in which the volume of liquid chamber 20a has contracted, and liquid L is being supplied from liquid chamber 20a to the ejection head 11 side. State ST63 shows a state in which approximately 50% of the maximum capacity of liquid chamber 20a has been supplied to the ejection head 11 side. Whether liquid is actually transported depends on the state of negative pressure maintenance unit 50, which will be discussed later. As the supply of liquid L progresses, the state reaches state ST51 in Figure 5, and the same operation is repeated.

[0059] (Detection of remaining amount) Detection of the remaining amount of liquid L in the liquid chamber 20a will be described with reference to Figure 7. Figure 7 is an explanatory diagram of the remaining amount detection operation in the intermediate tank 20. As described above, rotation of the detection lever 70 is detected by remaining amount detection sensors 71 and 72 arranged inside the housing 21A. To make the detection operation easier to understand, Figure 7 is a diagram in which the remaining amount detection sensors 71 and 72 and the detection lever 70 have been added to the diagrams of the internal configuration and operation of the intermediate tank 20 shown in Figures 5 and 6.

[0060] The detection lever 70 includes a detection piece 70c. The detection piece 70c is located inside the housing 21A. In this embodiment, the remaining amount detection sensors 71 and 72 are optical sensors, such as photointerrupters. The remaining amount detection sensors 71 and 72 are positioned at different positions on the rotation path of the detection piece 70c, and the detection piece 70c functions as a shielding plate that blocks the optical axes of the remaining amount detection sensors 71 and 72. The detection piece 70c may be located outside the housing 21A. In this case, a configuration can be adopted in which a portion of the detection lever 70 is laid out outside the housing 21A, and the remaining amount detection sensors 71 and 72 can also be located outside the housing 21A. When the remaining amount detection sensors 71 and 72 are located inside the housing 21A, their wiring harnesses can be extended outside the housing 21A via a sealing structure, such as a hermetic seal.

[0061] 7 shows a state ST71 in which the liquid chamber 20a is filled with 100% of the maximum volume of the liquid L. In this state, the detection piece 70c is positioned away from both the remaining amount detection sensors 71 and 72 and is not detected.

[0062] 7 shows a state ST72 in which the liquid L has flowed out of the liquid chamber 20a and the remaining amount is 60% of the maximum volume. In this state, the detection piece 70c is detected by the remaining amount detection sensor 71, but is not detected by the remaining amount detection sensor 72.

[0063] 7 shows a state ST73 in which the liquid L further flows out of the liquid chamber 20a and the remaining amount is 40% of the maximum volume. In this state, the detection piece 70c is detected by both the remaining amount detection sensors 71 and 72.

[0064] 7 shows a state ST74 in which the liquid L further flows out of the liquid chamber 20a and the remaining amount is 10% or less of the maximum volume. In this state, the detection piece 70c is not detected by the remaining amount detection sensor 71 but is detected by the remaining amount detection sensor 72.

[0065] 8 is an explanatory diagram for determining the remaining amount of liquid L in the liquid chamber 20a. In this embodiment, the estimated remaining amount of liquid L is divided into regions I to IV. Region I is a region corresponding to a remaining amount of 60% to 100%, region II is a region corresponding to a remaining amount of 40% to 60%, region III is a region corresponding to a remaining amount of 10% to 40%, and region IV is a region corresponding to a remaining amount of 10% or less.

[0066] Each region is defined by a threshold value corresponding to the rotation position of the detection lever 70. Region I and Region II are distinguished by a threshold value Low. The threshold value Low corresponds to the rotation position of the detection lever 70 when the detection result of the remaining amount detection sensor 71 is detection and the detection result of the remaining amount detection sensor 72 is non-detection. Region II and Region III are distinguished by a threshold value Out. The threshold value Out corresponds to the rotation position of the detection lever 70 when the detection result of the remaining amount detection sensors 71 and 72 are both detection. Region III and Region IV are distinguished by a threshold value Empty. The threshold value Empty corresponds to the rotation position of the detection lever 70 when the detection result of the remaining amount detection sensor 71 is non-detection and the detection result of the remaining amount detection sensor 72 is detection.

[0067] Regions I to IV can be identified from the detection results of the remaining amount detection sensors 71 and 72, and switching can be performed between the replenishing operation and the supplying operation. The remaining amount of liquid L can also be estimated by also using the ejection amount of liquid L ejected from the ejection head 11. In this case, the number of dots of liquid L ejected from the ejection head 11 can be counted and accumulated, and then multiplied by the average ejection amount per dot to calculate an approximate value of the amount of liquid consumed (so-called dot count). By also using dot count, the remaining amount can be estimated more precisely than the distinction between the four regions I to IV.

[0068] (Backflow prevention valve) The structure of the check valves 30 and 40 will be described with reference to Fig. 9. Fig. 9 is an explanatory diagram of the structure of the check valves 30 and 40.

[0069] The check valve 30 includes an upper housing member 31, a lower housing member 32, and a diaphragm 33 sandwiched between them. The diaphragm 33 is a flexible membrane molded from rubber or elastomer resin. The housing member 32 has an inlet pipe 32a forming an inlet for the liquid L and an outlet pipe 32b forming an outlet. The inlet pipe 32a is connected to the piping 19a, and the outlet pipe 32b is connected to the piping 19b. A communication passage 30a for the liquid L, which communicates with the outlet, is formed between the housing members 31 and 32. The diaphragm 33 has a through-hole 33a through which the liquid L passes. The diaphragm 33 is disposed between the communication passage 30a and the inlet pipe 32a and is pressed against the housing member 32 by a coil spring 34, blocking communication between the communication passage 30a and the inlet pipe 32a.

[0070] The check valve 30 operates as a so-called differential pressure valve. When the pressure in the inlet pipe 32a and the pressure in the outlet pipe 32b are equal, the coil spring 34 presses the diaphragm 33 against the housing member 32, blocking communication between the communication passage 30a and the inlet pipe 32a, as shown in Figure 9. In other words, the flow path of the fluid L is blocked. Similarly, when the pressure in the inlet pipe 32a is lower than the pressure in the outlet pipe 32b, the flow path of the fluid L is blocked.

[0071] On the other hand, when the pressure in the inlet pipe 32a is higher than the pressure in the outlet pipe 32b, the diaphragm 33 is lifted from the housing member 32 near the through-hole 33a, and the inlet pipe 32a and the outlet pipe 32b communicate with each other via the through-hole 33a and the communication passage 30a. In other words, the flow path of the fluid L is opened.

[0072] Due to the above-mentioned action, when the liquid chamber 20a of the intermediate tank 20 becomes negative pressure, the check valve 30 opens and the liquid L is sucked into the liquid chamber 20a from the container 17. Conversely, when the liquid chamber 20a of the intermediate tank 20 becomes positive pressure, the check valve 30 closes and prevents the liquid L from flowing back from the liquid chamber 20a to the container 17.

[0073] The check valve 40 includes an upper housing member 41, a lower housing member 42, and a diaphragm 43 sandwiched between them. The diaphragm 43 is a flexible membrane molded from rubber or elastomer resin. The housing member 42 has an inlet pipe 42a forming an inlet for the liquid L and an outlet pipe 42b forming an outlet. Pipe 19c is connected to the inlet pipe 42a, and pipe 19d is connected to the outlet pipe 42b. A communication passage 40a for the liquid L, which communicates with the outlet, is formed between the housing members 41 and 42. The diaphragm 43 has a portion that blocks the outlet pipe 42b, and this portion is pressed toward the housing member 42 by a coil spring 44 via a pressure plate 45, blocking the communication between the communication passage 40a and the outlet pipe 42b.

[0074] The check valve 40 also functions as a so-called differential pressure valve. When the pressure in the inlet pipe 42a and the pressure in the outlet pipe 42b are equal, the coil spring 34 presses the diaphragm 43 toward the housing member 42, as shown in Figure 9, blocking the communication between the communication passage 40a and the outlet pipe 42b. In other words, the flow path of the fluid L is blocked. Similarly, when the pressure in the inlet pipe 42a is lower than the pressure in the outlet pipe 42b, the flow path of the fluid L is blocked.

[0075] On the other hand, when the pressure in the inlet pipe 42a is higher than the pressure in the outlet pipe 42b, the diaphragm 43 is lifted, and the inlet pipe 42a and the outlet pipe 42b communicate with each other via the communication passage 40a. In other words, the flow path of the fluid L is opened.

[0076] Due to the above action, when the liquid chamber 20a of the intermediate tank 20 becomes positive pressure, the check valve 40 opens and the liquid L is supplied from the liquid chamber 20a to the ejection head 11 side. Conversely, when the liquid chamber 20a of the intermediate tank 20 becomes negative pressure, the check valve 40 closes and the liquid L is prevented from flowing back from the ejection head 11 side to the liquid chamber 20a.

[0077] It is also possible to carry out a process called a suction operation, in which a negative pressure is applied to the nozzle portion of the discharge head 11 using a negative pressure pump (not shown). In this case, the pressure chamber 20b is set to atmospheric pressure, and the liquid chamber 20a is set to atmospheric pressure. That is, this process is carried out with the pressure inside the inlet pipe 42a at approximately atmospheric pressure. By putting a positive pressure into the pressure chamber 20b, the backflow prevention valve 40 is opened, and the liquid L can be sent at a high flow rate from the liquid chamber 20a to the discharge head 11 in one go.

[0078] (Negative pressure maintenance unit) The structure and operation of the negative pressure maintaining unit 50 will be described with reference to Fig. 10. Fig. 10 is an explanatory diagram of the structure and operation of the negative pressure maintaining unit 50. State ST101 shows a state in which the amount of stored liquid L is large, and state ST102 shows a state in which the amount of stored liquid L is small.

[0079] The negative pressure maintaining unit 50 includes a housing 51 in which the discharge head 11 is provided, and constitutes a discharge head module. The housing 51 has an inlet pipe 51a that forms an inlet through which the liquid L supplied from the intermediate tank 20 flows in, and a flow path 51b that communicates with the inlet pipe 51a. The inlet pipe 51a is connected to the piping 19d. A filter 53 is provided in the flow path 51b, and unnecessary impurities are removed from the liquid L that has flowed into the flow path 51b as it passes through the filter 53.

[0080] The housing 51 also has flow paths 51c and 51e and a reservoir 50a. A portion of the peripheral wall of the reservoir 50a is formed by a diaphragm 52. The reservoir 50a is provided between the liquid chamber 20a of the intermediate tank 20 and the ejection head, and is in communication with the ejection head 11 via the flow path 51e. The reservoir 50a is a liquid chamber that temporarily stores the liquid L supplied from the liquid chamber 20a at a predetermined negative pressure just before the ejection head 11, and prevents the liquid L from leaking out of the ejection head 11.

[0081] Diaphragm 52 is a deformable sheet member made of a flexible material that defines storage section 50a. Moving plate 56 is in close contact with diaphragm 52. Diaphragm 52 and moving plate 56 are constantly biased by elastic member 57 in a direction that increases the volume of storage section 50a. Elastic member 57 is a coil spring installed between housing 51 and moving plate 56, and the biasing force of elastic member 57 maintains storage section 50a in a negative pressure state.

[0082] The flow path 51c is provided with a restriction valve 54 that restricts the supply of liquid L from the flow path 51c to the reservoir 50a. The restriction valve 54 opens and closes a communication path 51d between the flow path 51c and the reservoir 50a. The restriction valve 54 includes a valve body 54a and an elastic member 54b, and the valve body 54a is constantly biased in the closing direction by the elastic member 54b. The valve body 54a has a shaft that passes through the communication path 51d and advances into the reservoir 50a.

[0083] The operation of the negative pressure maintenance unit 50 will now be described. In state ST101, the restriction valve 54 is closed; in other words, the reservoir 50a is filled with a sufficient amount of liquid L. The valve element 54a is in close contact with the wall surrounding the communication passage 51d, restricting the inflow of liquid L from the flow path 51c into the reservoir 50a. In this state, a force is applied to the diaphragm 52 from the elastic member 57 via the moving plate 56 in a direction that expands the reservoir 50a. Furthermore, because the restriction valve 54 is closed, the liquid inside the reservoir 50a is under negative pressure. This allows the meniscus formed at the nozzle to be in a desirable state (a moderately concave state) when the liquid L is ejected from the nozzle of the ejection head. Note that in state ST101 in FIG. 10, the bulge of the diaphragm 52 is depicted somewhat exaggerated.

[0084] State ST102 shows a state in which the restriction valve 54 is open. In other words, when the amount of liquid remaining in the storage section 50a is insufficient, the system is waiting for a liquid supply from the intermediate tank 20. When the amount of liquid L in the storage section 50a decreases due to the discharge of the liquid L from the discharge head, the diaphragm 52 is displaced toward the restriction valve 54 against the elastic member 57. The moving plate 56 presses the valve body 54a of the restriction valve 54, and the valve body 54a moves away from the wall portion surrounding the communicating passage 51d, allowing the liquid L to flow from the flow path 51c into the storage section 50a via the communicating passage 51d. The liquid L entering from the inflow pipe 51a is pressurized, so it passes through the filter 53 and flows into the storage section 50a through the communicating passage 51d.

[0085] As the amount of liquid in reservoir 50a increases, diaphragm 52 gradually expands, and at the same time, moving plate 56 also moves in a direction away from valve body 54a, resulting in restriction valve 54 becoming closed as in state ST101.

[0086] In this way, while maintaining a negative pressure in the storage section 50a, the liquid L is supplied under pressure from the intermediate tank 20 to the storage section 50a. Although the displacement of the diaphragm 52 is exaggerated in Figure 10, in reality, the storage section 50a can be repeatedly closed and opened with a small amount of movement, maintaining a substantially constant negative pressure inside the storage section 50a.

[0087] (Pressure adjustment unit) The configuration of the pressure adjustment unit 60 will now be described. Fig. 11 is an explanatory diagram of the pressure adjustment unit 60. The pressure adjustment unit 60 includes an air pump 61 and a plurality of control valves 62A to 62D. The air pump 61 is an electric pump equipped with a diaphragm and a check valve therein, and is driven by a motor. The plurality of control valves 62A to 62D are electric valves that switch the communication state between the air pump 61 and the pressure chamber 20b or the pipe 19f that forms the atmosphere communication path.

[0088] In this embodiment, a pressure sensor 73 and a constant pressure valve 63 are provided in the pipe 19e. The pressure sensor 73 detects the pressure of the gas in the pipe 19e, i.e., the pressure of the pressure chamber 20b. The constant pressure valve 63 is a valve that maintains the pressure chamber 20b at or below an upper limit pressure when the pressure in the pressure chamber 20b is pressurized. When the pressure in the pipe 19e reaches the upper limit pressure, the constant pressure valve 63 opens, connecting the pipe 19e to the atmosphere. This maintains the pressure chamber 20b at or below the upper limit pressure.

[0089] Fig. 12 is a timing chart showing the opening and closing patterns of the control valves 62A to 62D. In the figure, valves A to D refer to the control valves 62A to 62D. The horizontal axis indicates pressurization, sealing, atmosphere release A, depressurization, atmosphere release B, and pressurization, indicating the operation of the pressure adjustment unit 60 with respect to the pressure chamber 20b. Fig. 13 is an explanatory diagram of the operation when the control valves 62A to 62D are opened and closed in the order of pressurization, sealing, atmosphere release A, depressurization, and atmosphere release B shown on the horizontal axis of Fig. 12.

[0090] State ST131 in Figure 13 is the valve state for pressurizing the pressure chamber 20b to a positive pressure state. Control valve 62A is open, control valve 62B is closed, control valve 62C is open, and control valve 62D is closed. By driving the air pump 61 in each of these valve states, air is sucked in from the pipe 19f side and pressurized air is sent to pipe 19e. When pressure is adjusted by this pressurizing operation, the pressure chamber 20b gradually changes from atmospheric pressure to a positive pressure. When the pressure in pipe 19f exceeds the upper limit pressure after a predetermined time, the constant pressure valve 63 operates and the pressure in pressure chamber 20b becomes constant.

[0091] State ST132 is a valve state for sealing operation to maintain the pressure in pressure chamber 20b pressurized by the pressurizing operation. Control valve 62A is closed, control valve 62B is open, control valve 62C is open, and control valve 62D is closed. In each of these valve states, the pipe 19e side (pressure chamber 20b) is isolated from the air pump 61 and sealed. Furthermore, when the air pump 61 is driven, air circulates between control valves 62B and 62C and the air pump 61. Therefore, no air flows through the pipe 19f side, whether the air pump 61 is operating or stopped.

[0092] State ST133 is an atmosphere release A operation that is passed through on the way to the next depressurization operation. This operation is an operation for quickly changing the pressure chamber 20b, which is in a positive pressure state, to a negative pressure state by connecting the pressure chamber 20b to the atmosphere and returning the positive pressure state to near atmospheric pressure. In the atmosphere release A operation, the control valve 62A is closed, the control valve 62B is open, the control valve 62C is open, and the control valve 62D is open. In this case, air enters from the side of the pipe 19e, passes through the control valve 62D and the control valve 62C, and then exits to the pipe 19f without passing through the air pump 61.

[0093] State ST134 is the valve state for decompression operation to place pressure chamber 20b in a negative pressure state. Control valve 62A is closed, control valve 62B is open, control valve 62C is closed, and control valve 62D is open. By operating the air pump 61 in each of these valve states, air is sucked in from the pipe 19e side and exhausted to the pipe 19f side. When pressure chamber 20b is at atmospheric pressure and pressure is adjusted by this decompression operation, pressure chamber 20b gradually becomes negative. After a predetermined time, the pressure in pressure chamber 20b becomes constant at a predetermined negative pressure according to the capacity of air pump 61. Note that in this embodiment, no negative pressure constant valve is provided, but if it is desired to limit the pressure at a predetermined negative pressure, a negative pressure constant valve may be provided in parallel with constant pressure valve 63.

[0094] State ST135 is an atmosphere release B operation that is passed on the way to the next pressurization operation (state ST131). This operation is an operation for connecting pressure chamber 20b to the atmosphere to quickly change the interior of pressure chamber 20b, which is in a negative pressure state, to a positive pressure state, thereby returning the pressure chamber 20b from negative pressure to near atmospheric pressure. In atmosphere release B operation, control valve 62A is open, control valve 62B is open, control valve 62C is open, and control valve 62D is open. In this case, air enters from the side of pipe 19f, passes through control valve 62B and control valve 62A, and then enters pipe 19e without passing through air pump 61.

[0095] 14 is a diagram showing a specific structural example of the pressure adjustment unit 60. In this structural example, an air pump 61, control valves 62A to 62D, a constant pressure valve 63, a motor as a drive source, a position detection sensor, etc. are all unitized.

[0096] The motor 61a drives the air pump 61 and the control valves 62A to 62D. The cam sensor 65 detects the initial position of the cam member 64. The drive gear train 660 selectively transmits the drive force of the motor 61a to the air pump 61 and the cam member 64. The drive gear train 660 also includes a clutch mechanism. Normally, when the motor 61a is rotated in the forward direction, the cam member 64 does not move and only the air pump 61 operates. However, the clutch mechanism can also be used to rotate the motor 61a in the forward direction and rotate the cam member 64 in the reverse direction. The cam member 64 includes a camshaft and multiple plate cams that provide the timing and force to switch the control valves 62A to 62D.

[0097] FIG. 15 is a schematic cross-sectional view showing the configuration of a representative control valve 62A. The cam lever 66 functions as a cam follower for the cam member 64 and displaces the valve rubber 622. The cam lever spring 67 biases the cam lever 66 in the direction of closing the valve. The valve rubber 622 forms an airtight space and presses a portion against an opposing portion to perform the valve function itself. The seal portion 622A is a part of the valve rubber 622 and is a valve element that deforms when pressed against an opposing portion to form a seal. The flow path 620 is the flow path upstream of the control valve 62A, and the flow path 621 is the flow path downstream of the control valve 62A. The cam lever 66 rotates as the cam member 64 rotates, displacing the seal portion 622A. This allows communication between the flow paths 620 and 621 to be switched between open and closed.

[0098] The positions of the cam member 64 corresponding to the pressurizing operation, sealing operation, atmosphere release A operation, depressurizing operation, and atmosphere release B operation illustrated in Figures 12 and 13 may be referred to as the pressurizing position, sealing position, atmosphere release A position, depressurizing position, and atmosphere release B position, respectively.

[0099] In this embodiment, the valve rubber 622 is integrated as a common component of the control valves 62A to 62D and the constant pressure valve 63. Fig. 16 is a perspective view of the valve rubber 622. In addition to the above-mentioned seal portion 622A, the valve rubber 622 has seal portions 622B to 622D that form the control valves 62B to 62D and a seal portion 63a that forms the constant pressure valve 63. These seal portions 622A to 622D and 63a have their own diaphragms for the control valves 62A to 62D and the constant pressure valve 63, and can operate independently, but are integrally molded as a component of the valve rubber 622.

[0100] The pressure state of the pressure chamber 20b can be adjusted by the pressure adjustment unit 60 configured as described above. The operation of the pressure adjustment unit 60 is roughly divided into the operation of the air pump 61 and the switching operation of the control valves 62A to 62D.

[0101] When the air pump 61 operates, the drive gear train 660 is configured so that the drive force from the motor 61a is transmitted only to the air pump 61. Specifically, the air pump 61 is continuously driven while the motor 61a is rotating in the forward direction. When the control valves 62A to 62D are switched, the motor 61a is rotated in the reverse direction. In this case, the drive gear train 660 is configured so that the drive force of the motor 61a is transmitted to both the air pump 61 and the cam member 64. When the motor 61a is rotated in the reverse direction, the air pump 61 is driven in the opposite direction to when the motor 61a is rotating in the forward direction, but the air pump 61 is configured to perform the same pumping action regardless of the direction in which it is driven.

[0102] The driving force transmitted to the cam member 64 causes the cam member 64 to rotate, and each of the control valves 62A to 62D opens and closes with the same mechanism and operation as the control valve 62A shown as a representative example in Fig. 15. That is, in the valve closed state shown in Fig. 15, the valve rubber 622 is pressed downward in the figure via the cam lever 66 by the action of the cam lever spring 67. The seal portion 622A is pressed against the opposing portion and deforms, thereby coming into close contact with the opposing portion, thereby blocking the flow paths 620 and 621.

[0103] When the cam member 64 rotates and the convex portion of the cam surface abuts against the cam lever 66, the cam lever 66 rotates clockwise in the figure against the cam lever spring 67. The valve rubber 622 is pulled upward in the figure, and the seal portion 622A separates from the opposing member, connecting the flow path 620 and the flow path 621. The cam surface of the cam member 64 is configured so that the control valves 62A to 62D open and close at appropriate timing according to the timing chart in Figure 12. It is possible to transition to the desired operating state simply by rotating the cam member 64 as needed.

[0104] In this embodiment, air is used as the fluid for adjusting the pressure of the pressure chamber 20b, but a liquid working fluid such as hydraulic pressure may also be used. In that case, instead of opening to the atmosphere, a buffer tank for the liquid working fluid may be provided, into which the liquid working fluid is released, and the buffer tank may be kept at atmospheric pressure.

[0105] <Control circuit> The control circuit of the supply unit 18 will now be described. FIG. 17 is a block diagram showing the control circuit 100 of the supply unit 18. The control circuit 100 comprises at least one processor and at least one storage device, and the processor executes a program stored in the storage device. Specifically, the control circuit 100 comprises a CPU 101, a RAM 102, and a ROM 103. The ROM 103 stores programs, various settings, etc. The RAM 102 is responsible for temporarily storing programs and control information, etc. The CPU 101 executes the program stored in the ROM 103.

[0106] The CPU 101 can communicate with a main control circuit 200 of the recording device 1 via an interface 104. The main control circuit 200 controls the recording operation, etc. The control performed by the control circuit 100 may be configured to be performed by the main control circuit 200.

[0107] A timer 105 measures time. A motor driver 106 drives the motor 61a in accordance with commands from the CPU 101. A motor encoder 61b detects the rotation direction and angle of the motor 61a. The CPU 101 can control the motor 61a based on the detection results of the motor encoder 61b, the cam sensor 65, the remaining amount detection sensors 71 and 72, and the pressure sensor 73.

[0108] <Control example> An example of control of the supply unit 18 executed by the CPU 101 of the control circuit 100 will be described.

[0109] (Replenishment operation) 18 and 19 are flowcharts showing an example of the refilling operation. This operation is performed when the remaining amount of liquid L in the liquid chamber 20a has decreased, to return the liquid to the full capacity of 100%, as shown in state ST62 in Fig. 6. This operation is basically performed when the remaining amount of liquid L in the liquid chamber 20a has decreased to region II or below.

[0110] In S101, it is confirmed that the cam member 64 is in the sealed position. In this embodiment, it is assumed that when the recording device 1 is in a standby state, the cam member 64 is in the sealed position and the pressure chamber 20b is maintained in a positive pressure state. If the recording device 1 is in a standby state, there is no need to re-pressurize the pressure chamber 20b when transitioning from the standby state to the next recording operation, thereby shortening the recording time. In addition, since the liquid flow path is pressurized, it is difficult for air to enter the flow path from the outside. In S101, if it is determined that the cam member 64 is in a different position, the motor 61a is driven based on the detection results of the cam sensor 6 and motor encoder 61b, and the cam member 64 is moved to the sealed position.

[0111] Next, in S102, the motor 61a is rotated in the reverse direction. This causes the cam member 64 to rotate in the forward direction, moving from the sealed position through the atmosphere release A position toward the reduced pressure position. When passing through the atmosphere release A position, the pressure chamber 20b communicates with the atmosphere via the pressure adjustment unit 60, so the positively pressurized air in the pressure chamber 20b is suddenly released, and the pressure in the pressure chamber 20b approaches atmospheric pressure.

[0112] In this embodiment, the cam member 64 simply passes through the atmosphere release position A without stopping, but if, for example, the flow path is narrow and it is difficult to exhaust air, the cam member 64 may be temporarily stopped at the atmosphere release position A.

[0113] Next, in S103, it is determined whether the cam member 64 has transitioned to the depressurized position. The motor 61a continues to be driven until the transition is complete. Once the transition is complete, the rotation direction of the motor 61a is reversed to the forward direction in S104. As a result, the rotation of the cam member 64 stops at the depressurized position and the air pump 61 begins to operate. The air in the pressure chamber 20b is exhausted by the pressure adjustment unit 60, and the pressure in the pressure chamber 20b is reduced. As the air pump 61 continues to be driven, the pressure in the pressure chamber 20b is reduced to a negative pressure value determined by the capacity of the air pump 61. In this case, the restriction unit 25 quickly operates to the state shown in state ST52 in FIG. 5.

[0114] Next, in S105, the amount of liquid L supplied from the container 17 to the liquid chamber 20a is monitored based on the detection results of the remaining amount detection sensors 71 and 72. Once it is confirmed that the remaining amount of liquid L has entered area I, the system waits for t1 seconds to maintain this state. This is because, due to flow rate restrictions, it takes some time for the remaining amount in the liquid chamber 20a to reach 100% of its full capacity. The time t1 is set in advance taking into account the viscosity of the liquid L, the cross-sectional area and length of the flow path from the container 17 to the liquid chamber 20a, and the like. After t1 seconds have elapsed, the remaining amount in the liquid chamber 20a is considered to have reached 100% of its full capacity.

[0115] If the remaining amount in the container 17 is insufficient, the container 17 may become empty after the remaining amount exceeds the threshold Low in Fig. 8, and the total capacity may not reach 100%. In this case, too, it is assumed that the container 17 has been replenished to 100% of its total capacity, and the remaining amount information is corrected based on the detection results of the remaining amount detection sensors 71 and 72 while the liquid in the liquid chamber 20a is consumed in a subsequent supply operation.

[0116] If it cannot be detected in S105 that the remaining amount has entered remaining amount region I, the process waits for t2 seconds in S106. If, after waiting for t2 seconds, it cannot be confirmed that the remaining amount does not exceed the threshold Low in FIG. 8 and is in region I, it is determined that the container 17 has become empty and the body replenishment operation cannot be completed. In this case, it is better to notify the user that the container 17 is empty, so the no liquid amount flag information is turned on in S107. This flag information being on is notified to the main control circuit 200, and the main control circuit 200 executes the corresponding process (notifying the user, etc.).

[0117] On the other hand, if the remaining amount in the liquid chamber 20a is not in region IV, the printing operation can be continued, and the process proceeds to the next step in this state.

[0118] With this, the replenishing operation itself is completed, so in order to move on to the next operation of supplying liquid L to the ejection head 11, in S109 the motor 61a is switched to rotate in the reverse direction. This causes the cam member 64 to start rotating in the forward direction again. The cam member 64 moves from the depressurized position through the atmosphere release B position toward the pressurized position. When passing through the atmosphere release B position, the pressure chamber 20b communicates with the atmosphere via the pressure adjustment unit 60, so air flows in from the outside into the pressure chamber 20b, which is at negative pressure, and the pressure of the pressure chamber 20b approaches atmospheric pressure.

[0119] In this embodiment, the cam member 64 simply passes through the atmosphere release B position without stopping, but if, for example, the flow path is narrow and it is difficult for air to flow in, the cam member 64 may be temporarily stopped at the atmosphere release B position.

[0120] Next, in S110, it is determined whether the cam member 64 has transitioned to the pressurized position. The motor 61a continues to be driven until the transition is complete. Once the transition is complete, in S111, the rotation direction of the motor 61a is reversed to the forward direction. This stops the rotation of the cam member 64 at the pressurized position, and the air pump 61 is in operation. The pressure chamber 20b is pressurized by air flowing in from the outside via the pressure adjustment unit 60. The maximum pressure of the pressure chamber 20b rises to the positive pressure value set by the constant pressure valve 63. Because this positive pressure value determines the supply pressure of the liquid supplied to the ejection head 11, it is desirable to set this value as accurately as possible. In this embodiment, the constant pressure valve 63 has an internal spring that releases air to the outside when the pressure exceeds the spring force. Therefore, this spring force must be highly accurate, or, if necessary, adjusted.

[0121] Next, in S112, it is determined whether the pressure in the pressure chamber 20b has exceeded a predetermined pressure (positive pressure) P1 based on the detection result of the pressure sensor 73. Here, P1 is a pressure slightly lower than the opening pressure of the constant pressure valve 63. If the pressure in the pressure chamber 20b has exceeded P1, the process proceeds to the next step. Note that although the pressure sensor 73 is provided in this embodiment, providing a pressure sensor increases costs, so if this is undesirable, a configuration without the pressure sensor 73 is possible. In this case, the time required for the pressure to sufficiently exceed the opening pressure of the constant pressure valve 63 is set, taking into account the capacity of the air pump 61, the volume of the pressure chamber 20b, etc. In other words, it may be determined that the target positive pressure value has been reached when the motor 61a has been driven for a set time since it started rotating in the forward direction in S111.

[0122] Next, in S113, the driving of the motor 61a is stopped temporarily. At this point, the pressure chamber 20b has already been pressurized to a predetermined positive pressure. That is, the stopper 27 of the restriction unit 25 is retracted, the local deformation of the wall 22 (elastic deformation of part A in state ST61 in FIG. 6) is eliminated, and the wall 22 is under positive pressure, resulting in a supply state of the liquid L. That is, the liquid in the liquid chamber 20a has begun to be transported toward the ejection head 11. Although this depends on the state from the intermediate tank 20 to the negative pressure maintenance unit 50, when a corresponding amount of liquid L flows into the storage section 50a, the volume of the liquid chamber 20a decreases, and the volume of the pressure chamber 20b increases accordingly. As a result, the pressure in the pressure chamber 20b decreases. Since it is necessary to keep the pressure in the pressure chamber 20b as constant as possible, the pressure state is checked in the next step.

[0123] Next, in S114, the detection result of the pressure sensor 73 is checked to see if the pressure in the pressure chamber 20b falls below pressure P1 even after a preset time t3 seconds has elapsed. If pressure P1 is maintained after t3 seconds have elapsed, it is determined that the amount of liquid transferred from the liquid chamber 20a to the ejection head 11 side is small, and the process proceeds to the next step. If the pressure in the pressure chamber 20b falls below pressure P1 within t3 seconds, re-pressurization is required. In S115, the motor 61a is rotated in the forward direction to re-pressurize the pressure chamber 20b. In this case, if the remaining amount of liquid in the liquid chamber 20a has decreased to region IV, liquid cannot be supplied to the ejection head 11 side no matter how much positive pressure is applied. Therefore, in S116, the remaining amount of liquid in the liquid chamber 20a is checked. If it has not decreased to region IV, the process returns to S114. If the remaining amount of liquid in the liquid chamber 20a has decreased to region IV, the process returns to S102 because the liquid chamber 20a needs to be refilled again.

[0124] Next, in S117, the remaining amount of liquid L in the liquid chamber 20a after the pressure in the pressure chamber 20b has stabilized (i.e., after the liquid supply operation to the ejection head 11 side has stopped) is checked. If the remaining amount is in region I, proceed to the next step. If the remaining amount is not within region I, another replenishment operation is required, so the process returns to S102.

[0125] Next, in S118, the motor 61a is rotated in the reverse direction to start moving the cam member 64 to the sealing position. When it is determined in S119 that the cam member 64 has completed moving to the sealing position, the rotation of the motor 61a is stopped in S120, and the processing ends.

[0126] (Supply operation) 20 is a flowchart showing an example of a supply operation process during a recording operation, that is, a process related to control of pressure management of the pressure chamber 20b during a recording operation.

[0127] At the start of a recording operation, in S201 it is confirmed that the cam member 64 is in the sealed position. This is the same process as S101 in Figure 18. Next, in S202, the motor 61a is rotated in the forward direction. Here, due to the action of the clutch mechanism in the drive gear train 660, the motor 61a rotates in the forward direction to rotate the cam member 64 in the reverse direction during the section from the sealed position back to the pressurizing position.

[0128] Next, in S203, it is determined whether the cam member 64 has transitioned to the pressurized position. Driving of the motor 61a continues until the transition is complete, and once the transition is complete, the motor 61a is stopped in S204. If the cam member 64 is in the pressurized position, rotating the motor 61a in the forward direction makes it possible to pressurize the pressure chamber 20b.

[0129] Next, in S205, the detection result of the pressure sensor 73 during the recording operation is monitored. If the pressure in the pressure chamber 20b is greater than pressure P1, the motor 61a remains stopped in S207. If the pressure in the pressure chamber 20b falls below pressure P1, the motor 61a is rotated in the forward direction in S206 to start pressurizing the pressure chamber 20b.

[0130] One reason for the pressure in the pressure chamber 20b decreasing is that the remaining amount of liquid in the liquid chamber 20a decreases due to the ejection of liquid L from the nozzles of the ejection head 11. Also, if there is a long waiting period during which no recording operation is performed, a small amount of air may leak from one of the parts sealing the pressure chamber 20b, causing the pressure to decrease. In such a case, the pressure chamber 20b is re-pressurized to the pressure required for the supply operation. Returning to S205, if the pressure in the pressure chamber 20b is greater than pressure P1, the motor 61a is stopped in S207 and the re-pressurization ends.

[0131] Next, in S208, it is determined whether the recording operation is continuing through communication with the main control circuit 200. If the recording operation is continuing, the process returns to S205 to continue monitoring the pressure in the pressure chamber 20b. If the recording operation has ended, the process proceeds to S209, where the motor 61a is rotated in the reverse direction to move the cam member 64 to the sealing position.

[0132] Next, in S210, it is determined whether the cam member 64 has transitioned to the sealed position. The motor 61a continues to be driven until the transition is complete, and once the transition is complete, the motor 61a is stopped in S211. This completes the control of the supply operation during the recording operation.

[0133] (Remaining amount detection) Fig. 21 is a flowchart showing an example of a process for detecting the remaining amount of ink in the ink chamber 20a during a recording operation. The process in Fig. 21 is executed appropriately together with the process shown in Fig. 20, and monitors the remaining amount of ink in the ink chamber 20a while monitoring the detection results of the remaining amount detection sensors 71 and 72 when the recording operation starts.

[0134] In S301, if the remaining amount is in region I (FIG. 8), the remaining amount continues to be monitored. If the remaining amount falls below the threshold Low (FIG. 8), the process proceeds to the next step. In S302, a replenishment operation is performed. The process related to the replenishment operation is as described with reference to FIGS. 18 and 19. Note that the replenishment operation during a recording operation is performed at a timing set so as not to stop the recording operation or reduce throughput.

[0135] Next, in S303, the remaining amount in the liquid chamber 20a after the replenishment operation is confirmed. If the remaining amount exceeds the threshold Low (FIG. 8) and falls within region I (FIG. 8), the process returns to S301 to continue monitoring the remaining amount. If the remaining amount falls below the threshold Low (FIG. 8), the process proceeds to the next step to confirm which region the remaining amount falls within and take appropriate action.

[0136] In S304, it is determined whether the remaining amount in the liquid chamber 20a is in Region II (FIG. 8). If the remaining amount is not in Region II, processing proceeds to S308. If the remaining amount is in Region II, processing proceeds to S305. Here, if the remaining amount does not exceed the threshold Low (FIG. 8) even after the replenishment operation in S302, it is determined that the container 17 is empty, and a flag is turned on in S107 of FIG. 18. However, since recording operation can still be continued in this state, if recording operation is in progress, the recording operation is not interrupted for the replenishment operation. Therefore, if it is determined in S304 that the remaining amount is in Region II, a warning that the liquid level is low is notified to the main control circuit 200 in S305. The main control circuit 200 can notify the user by displaying a warning, for example, using the operation unit 14.

[0137] In S306, the process branches depending on the user's response to the warning. The user can select the response via, for example, the operation unit 14. If the user selects to replace the container 17, the process proceeds to S307, where the user replaces the container 17, followed by the processing of the replenishment operation shown in Figures 18 and 19. The replenishment operation restores the remaining amount to region I (Figure 8), and the process then returns to S301. On the other hand, if the user determines that replacement of the container 17 is not necessary at that time and selects to continue the recording operation, the process proceeds to S315, where it is determined whether the remaining amount is in region II. The process of S315 is repeated until the remaining amount is no longer in region II, and when it is determined that the remaining amount is no longer in region II, the process proceeds to S308.

[0138] Next, in S308, it is determined whether the remaining amount in the liquid chamber 20a is in region III (FIG. 8). If the remaining amount is not in region III (FIG. 8), it can be determined that the remaining amount is already in region IV (FIG. 8), in which case the process proceeds to S313, which will be described later. If the remaining amount is in region III (FIG. 8), a warning that the liquid is running out is sent to the main control circuit 200 in S309. In S310, the main control circuit 200 can stop the recording operation at a good time and notify the user by displaying a warning urging the user to replace the container 17.

[0139] Next, in S311, the process branches depending on the user's response to the warning. The user can select the response via, for example, the operation unit 14. The user can choose to replace the container 17 on the spot, or to continue the recording operation despite the fact that there is almost no remaining amount. If the user selects to replace the container 17, the process proceeds to S307, where the user replaces the container 17 and then the replenishment operation shown in Figures 18 and 19 is performed. If the user selects to continue the recording operation, the process proceeds to the next step, S312.

[0140] In S312, it is determined whether the remaining amount in the liquid chamber 20a is in region IV (FIG. 8). If the remaining amount is not in region IV (FIG. 8), the recording operation is still possible, so the recording operation continues as is. If the remaining amount is in region IV (FIG. 8), the recording operation cannot be continued, so the process proceeds to S313.

[0141] In S313, a warning that the liquid level in the liquid chamber 20a has run out is sent to the main control circuit 200. The main control circuit 200 can notify the user by displaying a warning that the recording operation cannot continue, for example, using the operation unit 14. Then, in S314, the recording operation is stopped and the system waits until the user replaces the container 17.

[0142] Next, we will explain the remaining amount detection control at the end of standby time, which is used to check the remaining amount in the liquid chamber 20a when the recording apparatus 1 is turned on or after a long standby period. Figure 22 is a flowchart of this control. As a prerequisite for this control, when the recording apparatus 1 is turned off or before entering a long standby period, area information indicating in which area (Figure 8) the remaining amount in the liquid chamber 20a was is stored in RAM 102 as remaining amount information.

[0143] In S401, the area information Roff is read from RAM 102. Next, in S402, the current area information Ron is determined based on the detection results of the remaining amount detection sensors 71 and 72. Next, in S403, it is confirmed whether the area information Roff and the areas indicated by the area Ron match, and if they match, the normal startup operation is performed. Thereafter, if the recording device 1 is turned off or enters a long-term standby state, the area information Roff at that time is stored in RAM 102 in S404.

[0144] If the region information Roff and region information Ron do not match in S403, this means that the remaining amount of liquid in the liquid chamber 20a has changed during standby. In particular, if the region indicated by the region information Ron is a region with a smaller remaining amount of liquid Lno than the region information Roff, it is assumed that an unintended leak of liquid has occurred. Since a malfunction may have occurred in some part of the supply unit 18, error processing is performed in S405. Here, for example, a liquid leakage error is notified to the main control circuit 200. The main control circuit 200 then takes measures to prevent further recording operations from continuing, and can notify the user of the malfunction using the operation unit 14.

[0145] <Summary> The configuration and control described above have the effect of reducing variations in the supply pressure of the liquid L from the intermediate tank 20 to the discharge head 11, even immediately after the supply operation from the container 17 to the intermediate tank 20 has been performed. As a result, the discharge operation from the discharge nozzle of the discharge head 11 becomes stable.

[0146] Furthermore, by making the wall body 22 and the flexible member 26 into a diaphragm shape made of a flexible material, it is possible to create a mechanism with a simple configuration that allows the volume to be varied, which has the effect of reducing the size of the device and the cost of the device.

[0147] Furthermore, by independently driving the four control valves 62A to 62D in the pressure adjustment unit 60 and providing a closed position and an open-to-atmosphere position as cam positions, it becomes possible to maintain the pressure chamber 20b in a pressurized state during standby. This also has the effect of shortening the time required to change the pressure chamber 20b from positive pressure to negative pressure or from negative pressure to positive pressure.

[0148] In addition, in the pressure adjustment unit 60, the valve rubber 622 is integrally molded as a part shared by the control valves 62A to 62D, which has the effect of reducing the size and cost of the device. Furthermore, by integrating the function of the constant pressure valve 63 into the valve rubber 622, further reductions in size and cost of the device can be expected.

[0149] Furthermore, by constantly abutting the detection lever 70 against the abutment member 24 that moves integrally with the wall body 22 and detecting the swinging state of the detection piece 70c with the remaining amount detection sensors 71 and 72, it is possible to detect the remaining amount in the liquid chamber 20a. Furthermore, by using dot counting in combination, it is possible to detect the remaining amount more precisely. Furthermore, by detecting the remaining amount in the liquid chamber 20a, it is possible to detect that the remaining amount of liquid in the container 17 has run out without providing a sensor to detect the remaining amount in the container 17.

[0150] In addition, by configuring the device to detect whether there is a significant change in the remaining amount of liquid in the liquid chamber 20a before and after a long standby period in which no recording operation is performed, it becomes possible to detect unintended liquid leakage, which has the effect of improving reliability.

[0151] Second Embodiment In the first embodiment, an example of a configuration in which an independent supply unit 18 is provided for each container 17 has been described, but a configuration in which part of the configuration of the supply unit 18 is shared by a plurality of containers 17 may also be used.

[0152] Figure 23 is an explanatory diagram showing an example in which multiple intermediate tanks 20 are integrated. In the example of Figure 23, the formation units 21 of four intermediate tanks 20 are integrated, and the pressure chambers 20b are connected to each other. The four intermediate tanks 20 correspond to four colors of ink: yellow, magenta, cyan, and black, for example.

[0153] In this embodiment, only one communication pipe 21c is provided for the four intermediate tanks 20, and they share the pressure adjustment unit 60. The four pressure chambers 20b are controlled to the same pressure state.

[0154] In this embodiment, by sharing one pressure adjustment unit 60 among multiple intermediate tanks 20, it is possible to significantly reduce the number of parts, which has the effect of making the device more compact and reducing device costs. One constant pressure valve 63 is also sufficient. Because one constant pressure valve 63 is sufficient, even if relatively expensive high-precision valves are used, the supply of four types of liquid can be stabilized with high precision at low overall cost.

[0155] In this embodiment, a configuration is adopted in which four pressure chambers 20b are connected to each other, but as in the first embodiment, each pressure chamber 20b may be formed as a structurally independent pressure chamber 20b, and one pressure adjustment unit 60 may be connected in parallel to each pressure chamber 20b.

[0156] Furthermore, in this embodiment, the formation units 21 of the four intermediate tanks 20 are integrated, but the number can be selected as appropriate. For example, of the total four intermediate tanks 20, two intermediate tanks 20 may be integrated, and the remaining two intermediate tanks 20 may also be integrated. In this case, a total of two pressure adjustment units 60 are sufficient. As another example, of the total four intermediate tanks 20, three intermediate tanks 20 may be integrated, and the remaining one intermediate tank 20 may be an independent intermediate tank. In this case, a total of two pressure adjustment units 60 are sufficient. As another example, of the total four intermediate tanks 20, two intermediate tanks 20 may be integrated, and the remaining two intermediate tanks 20 may each be an independent intermediate tank. In this case, a total of three pressure adjustment units 60 are sufficient.

[0157] Third Embodiment In the first embodiment, the restriction unit 25 is configured to displace the flexible member 26 by utilizing the pressure difference between the pressure in the pressure chamber 20b and atmospheric pressure, but the configuration of the restriction unit 25 is not limited to this.

[0158] Figure 24(A) is an explanatory diagram showing the structure of another example of a regulating unit. The regulating unit 25A in this figure has a piston-type structure. Specifically, the regulating unit 25A has a piston 251 and a cylinder 252, and the piston 251 forms a partition wall of the air chamber 20c in the pressure chamber 20b. The sliding portion between the piston 251 and the cylinder 252 contains a lubricant that does not easily leak out. This lubricant has the effect of smoothing the movement of the piston 251 and a sealing effect that prevents air from passing through due to a pressure difference.

[0159] This configuration allows the piston 251 to move smoothly in the direction D1 while maintaining its sealing function. Therefore, the piston 251 retreats to the position shown by the solid line when the pressure chamber 20b is in a positive pressure state. When the pressure chamber 20b is in a negative pressure state, the piston 251 moves to the position shown by the dashed line, and by abutting against the abutment member 24, the displacement range of the wall 22 in the direction in which the liquid chamber 20a increases can be restricted.

[0160] FIG. 24(B) shows another example of a restriction unit 25B. This restriction unit 25B has a structure that restricts the displacement range of the wall body 22 by controlling an actuator. The restriction unit 25B includes a plate-shaped lifter 253, a pantograph-type link 254, and a solenoid 255 that serves as an actuator. The solenoid 255 displaces the plunger using an electric signal, and applies a driving force to the link 254. In a configuration that includes the restriction unit 25B, the air chamber 20c and the communicating pipe 21d are not required.

[0161] When the solenoid 255 is energized, it attracts the plunger. Since the tip of the plunger is connected to the link 254, a part of the link 254 is attracted. This displaces the link 254, moving the lifter 253 in the direction D1 to the position shown by the broken line.

[0162] By energizing the solenoid 255 in synchronization with the pressure reduction operation of the pressure adjustment unit 60, the lifter 253 is displaced, and when the pressure chamber 20b is in a negative pressure state, the displacement range of the wall body 22 in the direction in which the liquid chamber 20a increases due to contact with the abutment member 24 can be restricted. When the negative pressure state of the pressure chamber 20b is released, the restriction on the displacement range can be released by stopping the energization of the solenoid 255.

[0163] <Fourth embodiment> In the first embodiment, the remaining amount of liquid in the liquid chamber 20a is detected using two sensors, the remaining amount detection sensor 71 and the remaining amount detection sensor 72, but a single sensor may be used. In this case, an estimated value based on the number of dots of liquid L ejected from the ejection head 11 may be used.

[0164] FIG. 25 shows an example of the configuration of the remaining amount detection sensor in this embodiment, and is a configuration including only the remaining amount detection sensor 72 of the first embodiment (without the remaining amount detection sensor 71). FIG. 26 is an explanatory diagram of determining the remaining amount of liquid L in the liquid chamber 20a, and corresponds to a modified example of FIG. 8. In this embodiment, the estimated remaining amount of liquid L is divided into three regions: Regions I, III, and IV. Region I corresponds to a remaining amount of, for example, 40% to 100%, Region III corresponds to a remaining amount of, for example, 10% to 40%, and Region IV corresponds to a remaining amount of, for example, 10% or less. Regions I and III are distinguished by a threshold value Out. The threshold value Out corresponds to the position of the detection piece 70c when the detection result of the remaining amount detection sensor 72 switches from non-detection to detection. The threshold value Empty corresponds to the dot count.

[0165] The state shown in Figure 25 shows that the liquid in the liquid chamber 20a has flowed out to 40% of its total capacity. In this state, the remaining amount detection sensor 72 is in a state in which it has detected the detection piece 70c. The threshold value Empty is a threshold determined by so-called dot count detection, in which the number of dots of liquid ejected from the ejection head 11 is counted and accumulated, and then multiplied by the average remaining amount per dot to calculate an approximate value of the remaining amount consumed. Therefore, after the remaining amount detection sensor 72 detects the threshold Out, it uses dot count detection to predict where in region III the remaining amount in the liquid chamber 20a is. If this predicted value exceeds the threshold Empty, it is determined that it has entered region IV.

[0166] FIG. 27 is a flowchart relating to detection of the remaining amount of ink in the liquid chamber 20a in this embodiment, and is a flowchart that replaces the processing example of FIG.

[0167] The processing from S501 to S502 is the same as the processing from S301 to S302 in Fig. 21, and therefore description thereof will be omitted. If it is determined in S503 that the remaining amount has fallen below region I (Fig. 26), the processing proceeds to S504.

[0168] The processing from S504 to S506 is the same as the range from S309 to S311 in Fig. 21, so the description will be omitted. If replacement of the container 17 is selected in S506, the processing proceeds to S507, and after the replacement and replenishment operations of the container 17, the processing returns to S501. If continuation of the recording operation is selected, the processing proceeds to the next S508.

[0169] In S508, estimation of liquid consumption amount is started by the above-mentioned dot count detection. Next, in S509, it is determined whether the remaining amount in the liquid chamber 20a is in region IV (Fig. 26). If the remaining amount is not in region IV (Fig. 26), printing operation is still possible, so printing operation continues as is. If the remaining amount is in region IV (Fig. 26), printing operation cannot be continued, so the process proceeds to the next step.

[0170] In S510, a warning that the liquid level in the liquid chamber 20a has run out is sent to the main control circuit 200. The main control circuit 200 can notify the user by displaying a warning that the recording operation cannot continue, for example, using the operation unit 14. Then, in S511, the recording operation is stopped and the system waits until the user replaces the container 17.

[0171] With the above-described configuration and control, even with one remaining amount detection sensor, it is possible to determine the remaining amount in the liquid chamber 20a with almost the same accuracy as when two remaining amount detection sensors are used.

[0172] Fifth Embodiment As an example of integrating the multiple intermediate tanks 20 described in the second embodiment, an example of a unit integrating two sets of intermediate tanks will be described with reference to Figures 28 to 31. In each figure, components having the same functions as those already described will be assigned the same reference numerals and their description will be omitted. The restriction unit 25 is not shown.

[0173] 28 is a perspective view of the intermediate tank unit 20A of this embodiment. The intermediate tank unit 20A is a unit including two sets of intermediate tanks 20 arranged in the X direction, and the formation unit 21 forms two liquid chambers 20a and two pressure chambers 20b. The two pressure chambers 20b are connected to each other.

[0174] Figure 29 is a perspective view showing the internal structure of the intermediate tank unit 20A, with the housing 21A and some internal components removed. Figure 30 is a cross-sectional view taken along line AA in Figure 28. Figure 31 is a bottom view showing the internal structure of the intermediate tank unit 20A, with the housing 21A removed.

[0175] In the intermediate tank unit 20A of this embodiment, the two sets of intermediate tanks 20 are provided with a common housing 21A, and the detection levers 70 of the two sets of intermediate tanks 20 are disposed inside the housing 21A.

[0176] Meanwhile, the remaining amount detection sensor 72 that detects the rotation of the detection lever 70 is disposed outside the housing 21A. The housing 21A is made of a light-transmitting material such as a transparent or semi-transparent material, and has an uneven portion 21f that is undulating in the Y direction for each intermediate tank 20. In this embodiment, the two uneven portions 21f are formed at a position between the two liquid chambers 20a in the X direction and spaced apart in the Y direction.

[0177] Each remaining amount detection sensor 72 is a U-shaped optical sensor (photointerrupter) having a light-emitting element 72a and a light-receiving element 72b. The detection piece 70c of the U-shaped detection lever 70 is inserted into the convex portion of the concave-convex portion 21f, and the light-emitting element 72a and the light-receiving element 72b are inserted into the concave portions on both sides of the convex portion. Because the convex portion of the concave-convex portion 21f is optically transparent, light passes from the light-emitting element 72a to the light-receiving element 72b. Therefore, it is possible to detect whether the detection piece 70c is present between the light-emitting element 72a and the light-receiving element 72b. By disposing the remaining amount detection sensor 72 outside the housing 21A in this way, a signal transmission harness does not need to pass through the wall of the housing 21A, eliminating the need for sealing measures such as a hermetic seal. Furthermore, the remaining amount detection sensor 72 is easily replaced.

[0178] In this embodiment, one remaining amount detection sensor 72 is provided for one detection lever 70, as in the fourth embodiment, but two remaining amount detection sensors 71 and 72 may be provided for one detection lever 70, as in the first embodiment. Also, although an optical photointerrupter is used as the remaining amount detection sensor 72, other types of sensors may be used as long as they can detect the detection piece 70c through the housing 21A in a non-contact manner. For example, a sensor that detects magnetic changes or changes in capacitance may be used.

[0179] Furthermore, in the intermediate tank unit 20A of this embodiment, the components of the two intermediate tanks 20 are rotated 180 degrees around the Z axis. Therefore, the detection pieces 70c of the detection levers 70 are arranged facing each other in the region between the two liquid chambers 20a in the X direction. Furthermore, as shown in FIG. 31 , an X-direction region R1 occupied by one pair of detection lever 70 and remaining amount detection sensor 72 partially overlaps with an X-direction region R2 occupied by the other pair of detection lever 70 and remaining amount detection sensor 72. This arrangement allows the X-direction dimension of the intermediate tank unit 20A to be reduced, contributing to a more compact device.

[0180] Furthermore, the detection lever 70, excluding the arm portion including the end portion 70a (the portion extending in the Y direction above the liquid chamber 20a), is disposed outside the area where the wall body 22, the frame body 23, and the abutment member 24 are present in the XY plane. Furthermore, the middle portion 70b that forms the rotation center of the detection lever 70 is disposed within the displacement range of the wall body 22 in the Z direction, which is the displacement direction of the wall body 22. In other words, when viewed from the -Y direction, the middle portion 70b is positioned so as to overlap with the displacement range of the wall body 22. Therefore, even when the rotation range of the detection lever 70 is included, it is possible to dispose the detection lever 70 without increasing the space of the intermediate tank unit 20A in the Z direction for the detection lever 70.

[0181] Furthermore, the end 70a of the detection lever 70 abuts against the center of the disk-shaped abutment member 24. As a result, even if the wall body 22 undergoes uneven deformation and the abutment member 24 is displaced in the Z direction while tilting, the end 70a abuts against the vicinity of the center of the abutment member 24, making it possible to reduce remaining amount detection errors.

[0182] Furthermore, the distance from the intermediate portion 70b to the detection piece 70c is nearly twice as long as the distance from the intermediate portion 70b, which forms the rotation center of the detection lever 70, to the end portion 70a of the detection lever 70. The displacement of the detection piece 70c in the remaining amount detection sensor 72 is greater than the displacement of the abutting member 24, contributing to improved detection accuracy. While extending the distance from the intermediate portion 70b to the detection piece 70c contributes to improved detection accuracy, extending the distance too much has an impact on the device size. Therefore, the distance from the intermediate portion 70b to the detection piece 70c is preferably 4.0 times or less, and more preferably 3.0 times or less, of the distance from the intermediate portion 70b, which forms the rotation center of the detection lever 70, to the end portion 70a of the detection lever 70.

[0183] <Other embodiments> The present invention can also be realized by supplying a program that realizes one or more functions of the above-described embodiments to a system or device via a network or a storage medium, and having one or more processors in the computer of the system or device read and execute the program.The present invention can also be realized by a circuit (e.g., ASIC) that realizes one or more functions.

[0184] <Summary of the embodiment> The above-described embodiment discloses at least the following recording device, control method, storage medium, and program.

[0185] Item 1. a liquid chamber (20a) that receives liquid from a liquid container (17) and stores the liquid to be supplied to a discharge means (11) that discharges the liquid onto a recording medium, and a forming means (21) that forms a pressure chamber (20b) adjacent to the liquid chamber (20a); a wall (22) that separates the liquid chamber (20a) from the pressure chamber (20b) and that changes the volume of the liquid chamber (20a) by being displaced in accordance with the pressure of the pressure chamber (20b); a restricting means (25) provided in the pressure chamber (20b) for restricting displacement of the wall body (22) in accordance with the pressure of the pressure chamber (20b); a pressure adjusting means (60) for adjusting the pressure of the pressure chamber (20b), When the pressure chamber (20b) is in a negative pressure state, the wall (22) is displaced to increase the volume of the liquid chamber (20a), the restricting means (25) restricts the displacement range of the wall body (22) when the pressure chamber (20b) is in a negative pressure state, and releases the restriction on the displacement range when the negative pressure state of the pressure chamber (20b) is released; The pressure adjusting means (60) a replenishing operation of introducing liquid from the liquid container (17) into the liquid chamber (20a) by adjusting the pressure chamber (20b) to a negative pressure state; a supply operation of adjusting the pressure chamber (20b) to a positive pressure state and supplying liquid from the liquid chamber (20a) to the discharge means (11); A recording device (1).

[0186] Item 2. The recording device (1) according to item 1, a first check valve (30) provided in the flow path upstream of the liquid chamber (20a) in the liquid introduction direction, for preventing backflow of liquid from the liquid chamber; a second backflow prevention valve (40) provided in the flow path downstream of the liquid chamber (20a) in the liquid supply direction, for preventing backflow of liquid into the liquid chamber; A recording device (1).

[0187] Item 3. The recording device (1) according to item 1 or 2, The restricting means (25) is The pressure chamber (20b) is provided with a flexible member (26) that forms a partition wall of an air chamber (20c) that communicates with the atmosphere, When the pressure chamber (20b) is in a negative pressure state, the flexible member (26) is displaced so as to increase the volume of the air chamber (20c). A recording device characterized by:

[0188] Item 4. The recording device (1) according to item 3, The restricting means (25) includes a stopper (27) that is displaced by the displacement of the flexible member (26), When the pressure chamber (20b) is in a negative pressure state, the regulating means (25) positions the stopper (27) at a regulating position, thereby regulating the displacement range of the wall body (22). A recording device characterized by:

[0189] Item 5. The recording device (1) according to item 4, An abutment member (24) is fixed to the wall body (22), When the pressure chamber (20b) is in a negative pressure state, the stopper (27) at the regulating position comes into contact with the abutting member (24), thereby regulating the displacement range of the wall body (22). A recording device characterized by:

[0190] Item 6. The recording device (1) according to any one of items 1 to 5, a reservoir (50a) provided between the liquid chamber (20a) and the discharge means (11), communicating with the discharge means (11), and configured to store the liquid supplied from the liquid chamber (20a); a limiting valve (54) that limits the supply of liquid from the liquid chamber (20a) to the storage section (50a); A recording device characterized by:

[0191] Item 7. Item 6. The recording device (1) according to item 6, a diaphragm (52) that defines the storage section (50a); and biasing means (57) for biasing the diaphragm (52) in a direction to increase the volume of the storage portion (50a), the limiting valve (54) limits the supply of liquid in response to an increase in the volume of the storage section (50a) and releases the limit on the supply of liquid in response to a decrease in the volume of the storage section (50a); A recording device characterized by:

[0192] Item 8. The recording device (1) according to any one of items 1 to 7, a remaining amount detection means (71, 72) for detecting the remaining amount of liquid in the liquid chamber (20a), The pressure adjusting means (60) operates based on the detection result of the remaining amount detecting means (71, 72). A recording device characterized by:

[0193] Item 9. The recording device (1) according to any one of items 1 to 8, pressure detection means (73) for detecting the pressure in the pressure chamber (20b); The pressure adjusting means (60) operates based on the detection result of the pressure detecting means (73). A recording device characterized by:

[0194] Item 10. The recording device (1) according to item 5, When the pressure chamber (20b) is in a negative pressure state, the stopper (27) is positioned at the regulating position before the abutting member (24) abuts against the stopper (27). A recording device characterized by:

[0195] Item 11. The recording device (1) according to item 1, a second forming means (21) that forms a second liquid chamber (20a) that receives liquid from a second liquid container (17) and stores the liquid to be supplied to a second ejection means (11) that ejects the liquid onto a recording medium, and a second pressure chamber (20b) adjacent to the second liquid chamber (20a); a second wall (22) that separates the second liquid chamber (20a) from the second pressure chamber (20b) and that changes the volume of the second liquid chamber (20a) by being displaced in accordance with the pressure of the second pressure chamber (20b); a second regulating means (25) provided in the second pressure chamber (20b) and regulating the displacement of the second wall body (22) in accordance with the pressure of the second pressure chamber (20b); The pressure chamber (20b) and the second pressure chamber (20b) are in communication with each other. A recording device characterized by:

[0196] Item 12. The recording device (1) according to any one of items 1 to 11, The pressure adjusting means (60) a pump (61); a plurality of control valves (62A-62D) provided between the pump (61) and the pressure chamber (20b); By combining opening and closing of the plurality of control valves (62A-62D), the pump (61) performs the following operations: pressurizing the pressure chamber (20b), depressurizing the pressure chamber (20b), sealing the pressure chamber (20b), and opening the pressure chamber (20b) to the atmosphere. A recording device characterized by:

[0197] Item 13. Item 13. The recording device (1) according to item 12, The pressure adjusting means (60) includes a constant pressure valve (63) that maintains the pressure in the pressure chamber (20b) at or below an upper limit pressure when pressurizing the pressure chamber (20b). A recording device characterized by:

[0198] Item 14. The recording device (1) according to item 8, and a notification means (14) that prompts a user to replace the liquid container (17) when the detection result of the remaining amount detection means (71, 72) does not indicate an increase in the remaining amount even when the pressure adjustment means (60) performs the supply operation. A recording device characterized by:

[0199] Item 15. The recording device (1) according to item 8, and a control means (100) for stopping the recording operation based on the detection result of the remaining amount detection means (71, 72). A recording device characterized by:

[0200] Item 16. Item 16. The recording device according to item 15, the control means (100) performs the stop process based on the detection result of the remaining amount detection means (72) and the estimation result of the amount of liquid discharged by the discharge means (11). A recording device characterized by:

[0201] Item 17. Item 8. The recording device according to item 8, and a control means (100) for performing error processing based on the detection result of the remaining amount detection means (71, 72) and the estimation result of the amount of liquid discharged by the discharge means (11). A recording device characterized by:

[0202] Item 18. Item 8. The recording device according to item 8, The remaining amount detection means (71, 72) detects the displacement of the wall body (22). A recording device characterized by:

[0203] Item 19. Item 8. The recording device according to item 8, a lever member (70) that rotates in conjunction with the displacement of the wall body (22), The remaining amount detection means (71, 72) detects the rotation of the lever member (70). A recording device characterized by:

[0204] Item 20. Item 19. The recording device according to item 19, The wall (22) has a fixed periphery, The lever member (70) rotates in conjunction with the displacement of the central portion of the wall body (22). A recording device characterized by:

[0205] Item 21. Item 19. The recording device according to item 19, A pivot center portion (70b) of the lever member (70) is disposed within the displacement range of the wall body (22) in the displacement direction of the wall body (22). A recording device characterized by:

[0206] Item 22. Item 19. The recording device according to item 19, The forming means (21) is a hollow body that forms an outer wall that defines the liquid chamber (20a) and the pressure chamber (20b), The lever member (70) and the remaining amount detection means (71, 72) are disposed inside the hollow body. A recording device characterized by:

[0207] Item 23. Item 19. The recording device according to item 19, The forming means (21) is a hollow body that forms an outer wall that defines the liquid chamber (20a) and the pressure chamber (20b), The lever member (70) is disposed inside the hollow body, The remaining amount detection means (72) is disposed outside the hollow body. A recording device characterized by:

[0208] Item 24. Item 23. The recording device according to item 23, the outer wall of the hollow body is made of a light-transmitting material, The remaining amount detection means (72) is a sensor that optically detects the lever member (70). A recording device characterized by:

[0209] Item 25. The recording device according to item 1, a lever member (70) that rotates in conjunction with the displacement of the wall body (22); a remaining amount detection means (72) for detecting the rotation of the lever member (70) to detect the remaining amount of liquid in the liquid chamber (20a), a first set of the liquid chamber (20a), the pressure chamber (20b), the wall body (22), the lever member (70), and the remaining amount detection means (72); a second set of the liquid chamber (20a), the pressure chamber (20b), the wall body (22), the lever member (70), and the remaining amount detection means (72), The liquid chambers (20a) of the first set and the liquid chambers (20a) of the second set are arranged in a first direction (X), an arrangement area (R1) of the lever members (70) and the remaining amount detection means (72) of the first set and an arrangement area (R2) of the lever members (70) and the remaining amount detection means (72) of the second set are arranged so as to overlap in the first direction (X); A recording device characterized by:

[0210] Item 26. a liquid chamber (20a) that receives liquid from a liquid container (17) and stores the liquid to be supplied to a discharge means (11) that discharges the liquid onto a recording medium, and a forming means (21) that forms a pressure chamber (20b) adjacent to the liquid chamber (20a); a wall (22) that separates the liquid chamber (20a) from the pressure chamber (20b) and that changes the volume of the liquid chamber (20a) by being displaced in accordance with the pressure of the pressure chamber (20a); a restricting means (25) provided in the pressure chamber (20a) for restricting displacement of the wall body (22) in accordance with the pressure of the pressure chamber (20a); a pressure adjusting means (60) for adjusting the pressure of the pressure chamber (20b), When the pressure chamber (20b) is in a negative pressure state, the wall (22) is displaced to increase the volume of the liquid chamber (20a), a control method for a recording device (1), wherein the regulating means (25) regulates a displacement range of the wall body (22) when the pressure chamber (20b) is in a negative pressure state, and releases the regulation of the displacement range when the negative pressure state of the pressure chamber (22) is released, an introducing step of adjusting the pressure chamber (20b) to a negative pressure state by the pressure adjusting means (60) and introducing liquid from the liquid container (17) into the liquid chamber (20a); a supply step of adjusting the pressure chamber (20b) to a positive pressure state by the pressure adjusting means (60) and supplying liquid from the liquid chamber (20a) to the discharge means (11), A control method comprising:

[0211] Item 27. A storage medium storing a program that causes a computer to execute the control method described in item 26.

[0212] Item 28. Item 27. A program that causes a computer to execute the control method described in Item 26.

[0213] The invention is not limited to the above-described embodiments, and various changes and modifications can be made without departing from the spirit and scope of the invention. Accordingly, the following claims are appended to apprise the public of the scope of the invention. [Explanation of symbols]

[0214] 1 recording device, 11 ejection head, 17 liquid container, 21 formation unit, 25 regulation unit, 60 pressure adjustment unit

Claims

1. a liquid chamber for receiving liquid from a liquid container and for storing the liquid to be supplied to a discharge means for discharging the liquid onto a recording medium, and a forming means for forming a pressure chamber adjacent to the liquid chamber; a wall that separates the liquid chamber from the pressure chamber and that changes the volume of the liquid chamber by being displaced in response to the pressure of the pressure chamber; a restricting means provided in the pressure chamber for restricting displacement of the wall body in accordance with the pressure of the pressure chamber; a pressure adjusting means for adjusting the pressure in the pressure chamber; the wall body is displaced so as to increase the volume of the liquid chamber when the pressure chamber is in a negative pressure state; the restricting means restricts the displacement range of the wall body when the pressure chamber is in a negative pressure state, and releases the restriction on the displacement range when the negative pressure state of the pressure chamber is released, The pressure adjusting means is a replenishing operation of adjusting the pressure chamber to a negative pressure state and introducing liquid from the liquid container into the liquid chamber; a supply operation of adjusting the pressure chamber to a positive pressure state and supplying liquid from the liquid chamber to the discharge means; A recording device characterized by:

2. 2. The recording device according to claim 1, a first check valve provided in the flow path upstream of the liquid chamber in the liquid introduction direction, the first check valve preventing backflow of liquid from the liquid chamber; a second backflow prevention valve provided in the flow path downstream of the liquid chamber in the liquid supply direction, the second backflow prevention valve preventing backflow of liquid into the liquid chamber; A recording device characterized by:

3. 2. The recording device according to claim 1, The restriction means is The pressure chamber includes a flexible member that forms a partition wall of an air chamber that communicates with the atmosphere, the flexible member is displaced so as to increase the volume of the air chamber when the pressure chamber is in a negative pressure state. A recording device characterized by:

4. 4. The recording device according to claim 3, the restricting means includes a stopper that is displaced by displacement of the flexible member, the restricting means restricts the displacement range of the wall body by positioning the stopper at a restricting position when the pressure chamber is in a negative pressure state. A recording device characterized by:

5. 5. The recording device according to claim 4, An abutment member is fixed to the wall body, When the pressure chamber is in a negative pressure state, the stopper at the regulating position comes into contact with the abutting member, thereby regulating the displacement range of the wall body. A recording device characterized by:

6. 2. The recording device according to claim 1, a reservoir portion provided between the liquid chamber and the discharge means, communicating with the discharge means, and configured to store the liquid supplied from the liquid chamber; a limiting valve that limits the supply of liquid from the liquid chamber to the storage portion, A recording device characterized by:

7. 7. The recording device according to claim 6, a diaphragm that defines the storage section; and biasing means for biasing the diaphragm in a direction to increase the volume of the storage portion, the restriction valve restricts the supply of liquid in response to an increase in the volume of the storage portion, and releases the restriction on the supply of liquid in response to a decrease in the volume of the storage portion; A recording device characterized by:

8. 2. The recording device according to claim 1, a remaining amount detection means for detecting the remaining amount of liquid in the liquid chamber; The pressure adjusting means operates based on the detection result of the remaining amount detecting means. A recording device characterized by:

9. 2. The recording device according to claim 1, a pressure detection means for detecting the pressure in the pressure chamber; The pressure adjusting means operates based on the detection result of the pressure detecting means. A recording device characterized by:

10. 6. The recording device according to claim 5, When the pressure chamber is brought into a negative pressure state, the stopper is positioned at the regulating position before the abutting member abuts against the stopper. A recording device characterized by:

11. 2. The recording device according to claim 1, a second liquid chamber that receives liquid from a second liquid container and stores the liquid to be supplied to a second ejection means that ejects the liquid onto a recording medium, and a second forming means that forms a second pressure chamber adjacent to the second liquid chamber; a second wall that separates the second liquid chamber from the second pressure chamber and that changes the volume of the second liquid chamber by being displaced in accordance with the pressure of the second pressure chamber; a second regulating means provided in the second pressure chamber and regulating displacement of the second wall body in accordance with the pressure in the second pressure chamber; The pressure chamber and the second pressure chamber are in communication with each other. A recording device characterized by:

12. 2. The recording device according to claim 1, The pressure adjusting means is A pump and a plurality of control valves provided between the pump and the pressure chamber; By combining opening and closing of the plurality of control valves, the pump performs an operation of pressurizing the pressure chamber, an operation of depressurizing the pressure chamber, an operation of sealing the pressure chamber, and an operation of opening the pressure chamber to the atmosphere. A recording device characterized by:

13. 13. The recording device according to claim 12, the pressure adjusting means includes a constant pressure valve that maintains the pressure in the pressure chamber at or below an upper limit pressure when pressurizing the pressure chamber; A recording device characterized by:

14. 9. The recording device according to claim 8, a notification unit that prompts a user to replace the liquid container when the detection result of the remaining amount detection unit does not indicate an increase in the remaining amount even after the pressure adjustment unit has performed the supply operation; A recording device characterized by:

15. 9. The recording device according to claim 8, a control unit that performs a process of stopping the recording operation based on the detection result of the remaining amount detection unit; A recording device characterized by:

16. 16. The recording device according to claim 15, the control means performs the stop process based on the detection result of the remaining amount detection means and the estimation result of the amount of liquid discharged by the discharge means. A recording device characterized by:

17. 9. The recording device according to claim 8, a control unit that performs error processing based on the detection result of the remaining amount detection unit and the estimation result of the amount of liquid discharged by the discharge unit; A recording device characterized by:

18. 9. The recording device according to claim 8, The remaining amount detection means detects the displacement of the wall body. A recording device characterized by:

19. 9. The recording device according to claim 8, a lever member that rotates in conjunction with the displacement of the wall body, The remaining amount detection means detects the rotation of the lever member. A recording device characterized by:

20. 20. The recording device according to claim 19, The wall has a fixed periphery, The lever member rotates in conjunction with the displacement of the central portion of the wall body. A recording device characterized by:

21. 20. The recording device according to claim 19, The pivot center portion of the lever member is disposed within the displacement range of the wall body in the displacement direction of the wall body. A recording device characterized by:

22. 20. The recording device according to claim 19, the forming means is a hollow body that forms an outer wall that defines the liquid chamber and the pressure chamber, The lever member and the remaining amount detection means are disposed inside the hollow body. A recording device characterized by:

23. 20. The recording device according to claim 19, the forming means is a hollow body that forms an outer wall that defines the liquid chamber and the pressure chamber, the lever member is disposed inside the hollow body, The remaining amount detection means is disposed outside the hollow body. A recording device characterized by:

24. 24. The recording device according to claim 23, the outer wall of the hollow body is made of a light-transmitting material, The remaining amount detection means is a sensor that optically detects the lever member. A recording device characterized by:

25. 2. The recording device according to claim 1, a lever member that rotates in conjunction with the displacement of the wall body; a remaining amount detection means for detecting the remaining amount of liquid in the liquid chamber by detecting the rotation of the lever member, a first set of the liquid chamber, the pressure chamber, the wall body, the lever member, and the remaining amount detection means; a second set of the liquid chamber, the pressure chamber, the wall body, the lever member, and the remaining amount detection means, the liquid chambers of the first set and the liquid chambers of the second set are arranged in a first direction; an arrangement area of ​​the lever member and the remaining amount detecting means of the first set and an arrangement area of ​​the lever member and the remaining amount detecting means of the second set are arranged so as to overlap in the first direction; A recording device characterized by:

26. a liquid chamber for receiving liquid from a liquid container and for storing the liquid to be supplied to a discharge means for discharging the liquid onto a recording medium, and a forming means for forming a pressure chamber adjacent to the liquid chamber; a wall that separates the liquid chamber from the pressure chamber and that changes the volume of the liquid chamber by being displaced in response to the pressure of the pressure chamber; a restricting means provided in the pressure chamber for restricting displacement of the wall body in accordance with the pressure of the pressure chamber; a pressure adjusting means for adjusting the pressure in the pressure chamber; the wall body is displaced so as to increase the volume of the liquid chamber when the pressure chamber is in a negative pressure state; a control method for a recording device, wherein the regulating means regulates the displacement range of the wall body when the pressure chamber is in a negative pressure state, and releases the regulation of the displacement range when the negative pressure state of the pressure chamber is released, an introducing step of adjusting the pressure chamber to a negative pressure state by the pressure adjusting means and introducing liquid from the liquid container into the liquid chamber; a supply step of adjusting the pressure chamber to a positive pressure state by the pressure adjusting means and supplying liquid from the liquid chamber to the discharge means, A control method comprising:

27. A storage medium storing a program for causing a computer to execute the control method according to claim 26.

28. A program that causes a computer to execute the control method according to claim 26.

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