JP2008230010A - Liquid ejector and liquid supply method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid ejector arranged not ejecting the liquid in a channel when a liquid storage means is removed from the channel, and to provide a liquid supply method. <P>SOLUTION: The liquid ejector comprises an ejection head for ejecting liquid toward an ejection object, a liquid supply source in which a liquid storage means 51 for storing liquid internally is attached removably to an attachment section, a channel 522 communicating with the liquid storage means 51 and allowing liquid to flow toward the liquid ejection head, a volume changing means 524 provided in the way of the channel 522 and changing the internal volume depending on the pressure when the liquid flows in, and a pressurizing means 54b provided to apply the air pressure under pressurized state to the volume changing means 524 and to release the pressurized state for the volume changing means when the liquid storage means 51 is removed from the attachment section. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a liquid ejection apparatus and a liquid supply method.

  In an ink jet printer, ink ejected from a print head is stored in an ink cartridge, and is supplied from the ink cartridge to the print head via an ink flow path.

  Here, among the above-described ink jet printers, there is a type that pushes ink into an ink flow path by pressurizing the inside of an ink cartridge with a pressurizing pump or the like. In this type of printer, the pressure (internal pressure) in the ink cartridge, the ink flow path, and the print head is higher than the atmospheric pressure by pressurization. Therefore, when the ink cartridge is removed from the cartridge holder, there is a problem that the ink in the ink flow path is ejected from the connection port with the ink cartridge. When such ejection occurs, there is a problem that the cartridge holder, the printing object, etc. are stained with ink.

  In order to solve such a problem, Patent Document 1 provides an air release valve between the ink cartridge and the pressure pump, and opens the air release valve before removing the ink cartridge. The technical contents for reducing the pressure of are disclosed.

JP 2001-212971 A

  In the configuration disclosed in Patent Document 1, the inside of the ink flow path is maintained at a high pressure. Therefore, it is difficult to solve the problem that ink is ejected from the connection port with the ink cartridge when the ink cartridge is attached or detached. Further, in the configuration disclosed in Patent Document 1, it is necessary to open the air release valve prior to taking out the ink cartridge, and the work of taking out the ink cartridge becomes complicated. In some cases, it is necessary to provide a portion for receiving ink corresponding to the ejection of ink.

  The present invention has been made based on the above circumstances, and an object of the present invention is to provide a liquid ejecting apparatus and a liquid supply method having a configuration in which the liquid in the flow path is not ejected when the liquid storage means is removed from the flow path. The purpose is to do.

  In order to solve the above-described problems, the present invention provides a liquid supply source in which a discharge head that discharges liquid toward a discharge target and a liquid storage unit that stores the liquid therein are detachably attached to the mounting portion. And a flow path that communicates with the liquid storage means and circulates the liquid toward the liquid discharge head, and a volume that is provided in the middle of the flow path and in which the liquid flows in and the internal volume varies depending on the pressure An air pressure can be exerted on the fluctuation means and the volume fluctuation means in a pressurized state, and when the liquid storage means is removed from the mounting portion, the pressure on the volume fluctuation means is released. Pressure means.

  In the case of such a configuration, volume changing means is provided in the middle of the flow path, and the volume changing means is provided so that the internal volume can be changed by applying air pressure by the pressurizing means. . Further, when removing the liquid storage means from the mounting portion, the pressurizing means releases the pressurization state for the volume changing means. Therefore, the volume changing means can be easily changed in the direction of increasing the internal volume by releasing from the pressurized state. As a result, even if the flow path is in a pressurized state and the liquid is about to be ejected from the connection portion between the flow path and the liquid storage means, the ejection is caused by the volume fluctuation means changing in the direction of increasing the internal volume. Can be suppressed. Accordingly, it is possible to prevent the occurrence of a problem that the liquid is ejected and the discharge target is soiled when the liquid storage unit is removed. Further, since it is possible to suppress the ejection of liquid, it is not necessary to provide a portion for receiving the ejected liquid, and it is possible to suppress an increase in cost.

  Further, in addition to the above-described invention, in another invention, the volume variation means is provided in the middle portion of the flow path and bends in accordance with the liquid pressure with respect to the staying recess for retaining the liquid and the staying recess. A pressure buffer chamber is formed by covering in a closed state, and a bending member that is covered by the pressurizing means and bends in a direction to come in contact with and separate from the retention recess according to the air pressure exerted by the pressurizing means is provided. To do.

  When configured in this way, a pressure buffering chamber is configured by the staying recess and the deflecting member, and this pressure buffering chamber corresponds to the volume changing means. If it does in this way, a bending member will bend in the direction which contacts / separates to a retention recessed part according to air pressure. Therefore, when removing the liquid storage means from the mounting portion, if the pressurization state by the pressurization means is released, the bending member moves away from the retention recess due to the pressure (hydraulic pressure) inside the pressure buffer chamber. The internal volume of the pressure buffering chamber increases and the pressure of the liquid (hydraulic pressure) can be absorbed. Accordingly, it is possible to prevent the occurrence of a problem that the liquid is ejected and the discharge target is soiled when the liquid storage unit is removed.

  Furthermore, in addition to the above-described invention, in another aspect of the invention, the pressurizing unit further covers the case member forming the pressurizing chamber and the air provided in the liquid storage unit by covering the flexible member in a state of being closed from the outside. Air is supplied to the chamber, and the communication chamber is provided with a communication hole that is inserted into the pressurizing chamber and communicates with the pressurizing chamber. When removing the liquid storage means, an air tube that is opened to the atmosphere and an air tube are used. And a pressurizing pump for pumping air into the pressure chamber and the air chamber.

  When comprised in this way, the pressurization chamber closed from the outside is formed in the inside of a case body. In addition, an air tube is inserted into the pressurizing chamber, and the pressurizing chamber communicates with the air tube via a communication hole. Therefore, the air pumped from the pressurizing pump is also supplied to the pressurizing chamber. Thereby, the inside of the pressurizing chamber can be brought into a pressurized state, and in a liquid supply state, the bending member can be maintained in a state of being pushed in from the pressurizing chamber side. Further, when removing the liquid storage means, the air tube is opened to the atmosphere, so that the pressure in the pressurizing chamber becomes equal to the atmospheric pressure, and the pressure inside the pressure buffer chamber becomes higher. Therefore, the pushing state of the bending member cannot be maintained, and the bending member bends in a direction protruding into the pressurizing chamber. As a result, the internal volume of the pressure buffer chamber increases, and the pressure of the liquid can be absorbed. Accordingly, it is possible to prevent the occurrence of a problem that the liquid is ejected and the discharge target is soiled when the liquid storage unit is removed.

  In addition to the above-mentioned inventions, in another invention, the staying recess is provided in a hard resin member, and the bending member is a thin film member.

  In this case, the bending member can be easily bent according to the pressure of the liquid and the pressure of the pressurizing chamber.

  Further, according to another invention, in addition to each of the above-described inventions, the flow path has flexibility that is flexible in accordance with the movement of the liquid discharge head, and also has flexibility that includes a tube line that allows the liquid to flow therethrough. And a plate-like tube connected to the flexible tube and provided on the upstream side of the liquid supply with respect to the flexible tube, and the retention recess is provided in the plate-like tube. Is.

  In such a configuration, the staying recess is provided in the plate-like tube on the upstream side of the flexible tube. Here, since the flexible tube has flexibility, the flexible tube is flexible in the expanding direction by pressurization by the pressurizing means. Therefore, when removing the liquid storage means, the flexible tube tends to contract due to the release of the pressurized state, and the liquid flows upstream as the contraction occurs. However, since the staying recess is present on the upstream side of the flexible tube, the liquid pressure (hydraulic pressure) can be absorbed. Accordingly, it is possible to prevent the occurrence of a problem that the liquid is ejected and the discharge target is soiled when the liquid storage unit is removed.

  In another invention, in addition to the above-described invention, the pressurizing chamber and the pressure buffering chamber have substantially the same pressure when the pressurizing pump is operated.

  In such a configuration, when the pressurizing pump is operated, the pressure in the pressurizing chamber and the pressure buffering chamber are approximately equal, so that the bending member does not bend toward the pressurizing chamber and can maintain an equilibrium state. .

  Further, another invention is a liquid supply method for supplying a liquid via a flow path from a liquid storage means provided detachably to a liquid supply source to the liquid discharge head, and in the middle of the flow path, When the liquid flows in and the volume changing means for changing the internal volume according to the pressure is provided, and when the liquid is supplied from the liquid storage means to the liquid discharge head, the air pressure is applied to the volume changing means. When exerting in a pressurized state and removing the liquid storage means from the liquid supply source, the volume changing means is brought into a non-pressurized state.

  In such a configuration, when supplying the liquid from the liquid storage means toward the liquid head, the air pressure is applied to the volume variation means in a pressurized state, and when the liquid storage means is removed from the liquid supply source. Since the volume changing means is in a non-pressurized state, in the non-pressurized state, it can be easily changed in the direction of increasing the volume inside the volume changing means. As a result, even if the flow path is in a pressurized state and the liquid is about to be ejected from the connection portion between the flow path and the liquid storage means, the ejection is caused by the volume fluctuation means changing in the direction of increasing the internal volume. Can be suppressed. Accordingly, it is possible to prevent the occurrence of a problem that the liquid is ejected and the discharge target is soiled when the liquid storage unit is removed. Further, since it is possible to suppress the ejection of liquid, it is not necessary to provide a portion for receiving the ejected liquid, and it is possible to suppress an increase in cost.

  Hereinafter, a printer 10 as a liquid ejection apparatus according to an embodiment of the present invention will be described with reference to FIGS. In the following description, the lower side refers to the side where the printer 10 is installed, and the upper side refers to the side away from the installed side. The direction in which the carriage 31 moves is the main scanning direction, and the direction perpendicular to the main scanning direction and the direction in which the print target P is conveyed is the sub-scanning direction. Further, the side on which the print target P is supplied will be described as a paper feed side, and the side on which the print target P is discharged will be described as a paper discharge side.

<Schematic configuration of printer>
First, an outline of the configuration of the printer 10 will be described. FIG. 1 is a perspective view showing a schematic configuration of a printer 10 according to an embodiment of the present invention, in which an upstream side of paper feeding is arranged on the front side, and a downstream side (paper discharging side) of paper feeding is arranged on the back side. FIG. FIG. 2 is a schematic diagram showing the configuration of the printer 10. The printer 10 according to the present embodiment includes a chassis 21, a housing 22, a carriage mechanism 30, a paper feed mechanism 40, an ink supply mechanism 50, a cleaning mechanism 60, and a control unit 70.

  Among these, the chassis 21 is a part where the lower surface side is in contact with the installation surface and a part on which various units are mounted. Further, a housing 22 indicated by a two-dot chain line in FIG. 1 is attached to the chassis 21. The housing 22 has a planar shape similar to that of the chassis 21 described above.

  As shown in FIGS. 1 and 2, the carriage mechanism 30 includes a carriage 31, a carriage shaft 32 on which the carriage 31 slides, and a print head 33. The carriage mechanism 30 includes a carriage motor (CR motor) 34, a gear pulley 35 attached to the CR motor 34, an endless belt 36, and the endless belt 36 between the gear pulley 35. And a driven pulley 37 to be provided. Among these, from the print head 33 (corresponding to the ejection head), ink (corresponding to the liquid) supplied via an ink supply mechanism 50 described later is ejected to the printing object P.

  As shown in FIG. 2, the paper feed mechanism 40 includes a paper feed motor (PF motor) 41 and a paper feed roller 42 to which the driving force from the paper feed motor 41 is transmitted.

  The printer 10 according to the present embodiment is a so-called off-carriage type in which an ink cartridge 51 (corresponding to a part of the liquid supply source and corresponding to the liquid storage means) is mounted on the chassis 21 side. Therefore, as shown in FIG. 1, the ink supply mechanism 50 of the printer 10 includes a cartridge holder 52, a pressurizing pump 53, an air tube 54, a flexible tube 55, and a sub tank 56. . In addition to these, the ink supply mechanism 50 also has a plate-like tube 500.

  Among these, the cartridge holder 52 shown in FIG. 3 (corresponding to a part of the liquid supply source and corresponding to the mounting portion) is a portion on which the ink cartridge 51 shown in FIG. It is attached. The cartridge holder 52 is provided with an insertion port 52 a for inserting the ink cartridge 51. In the present embodiment, one (two in total) cartridge holders 52 are provided inside the printer 10 and on the end side in the main scanning direction. Further, the mounting position of the cartridge holder 52 with respect to the chassis 21 is provided at a portion that is out of the moving space area of the carriage 31. Specifically, the cartridge holder 52 is provided on the outer side in the longitudinal direction from the region in which the carriage 31 reciprocates in the longitudinal direction, and is attached to, for example, the discharge side of the print object P from the region in which the carriage 31 reciprocates. It has been.

  In addition, a plurality (three in this embodiment) of ink cartridges 51 are detachably attached to the pair of cartridge holders 52 via the insertion ports 52a. As shown in FIG. 4 and the like, the ink cartridge 51 includes an air chamber 51b inside a casing 51a, and further an ink pack 51c that fills the inside of the air chamber 51b is accommodated. The ink pack 51c is a highly airtight bag-like member such as an aluminum pack, for example, and ink is accommodated inside the ink pack 51c.

  Further, as shown in FIG. 7, the ink cartridge 51 has an ink supply port 51d communicating with the inside of the ink pack 51c, and the ink supply needle 52b existing in the cartridge holder 52 is provided in the ink supply port 51d. Is inserted. A film (not shown) is attached to the ink cartridge 51 so as to cover the ink supply port 51d. When the ink cartridge 51 is attached to the cartridge holder 52, the ink supply needle 52b breaks through the film, and the ink supply needle 52b and the ink supply port 51d are connected in a state that allows ink to flow. Thereby, the ink in the ink pack 51c can be supplied to the pressure buffer chamber 523 side described later via the ink supply port 51d.

  Further, as shown in FIG. 7, the ink cartridge 51 is provided with a tube engaging portion 51e. The tube engaging portion 51e is a portion that communicates with the air chamber 51b and engages with a connection plug 54b provided at the end of the air tube 54. That is, when the ink cartridge 51 is attached to the cartridge holder 52, the tube engaging portion 51e and the connection plug 54b are engaged. Then, the air fed from the air tube 54 can be introduced into the air chamber 51b. When the ink cartridge 51 is removed, the tube engagement portion 51e and the connection plug 54b are disengaged. In that case, the inside of the air tube 54 is in a state of being opened to the atmosphere via the connection plug 54b.

  As shown in FIG. 1, a pressure pump 53 is connected to the cartridge holder 52. The pressurizing pump 53 corresponds to a part of the pressurizing unit, and sends air into the air chamber 51 b in the ink cartridge 51 through the air tube 54. Then, by increasing the pressure of the air chamber 51b, the ink pack 51c is deformed so as to be crushed. As a result of this deformation, the ink present in the ink pack 51c is pushed out into the plate-like tube 500, and the ink is passed through the pressure buffer chamber 523, the first ink flow path 532, etc. existing in the plate-like tube 500. Flows. The details of the configuration of the plate tube 500 will be described later.

  The air tube 54 has one end connected to the pressurizing pump 53 and the other end connected to a connection plug 54b. The material is made of a flexible material such as an elastomer resin. Is formed. The air tube 54 corresponds to a part of the pressurizing means. Further, the connection plug 54b of the air tube 54 engages with the tube engaging portion 51e. In this engaged state, when the pressurizing pump 53 is operated, air can be pumped into the air chamber 51b.

  As shown in FIG. 1, one end of the flexible tube 55 is connected to the downstream end of the ink flow in the plate-like tube 500. The flexible tube 55 is made of a flexible material such as an elastomer resin. Thereby, the flexible tube 55 is flexibly soft and does not hinder the reciprocation of the carriage 31 in the main scanning direction. Further, the flexible tube 55 has a hollow tube line (not shown) penetrating in the longitudinal direction. The ink flow paths 532 and 535 and the tube pipe line communicate with each other so that ink can be circulated satisfactorily.

  A sub tank 56 is connected to the other end of the flexible tube 55. In principle, the same number of sub-tanks 56 as the ink cartridges 51 are provided above the carriage 31. In the sub tank 56, the ink flowing through the ink flow paths 532 and 535 and the tube pipe is temporarily stored. The ink stored in the sub tank 56 is ejected from the print head 33 to the lower surface side of the carriage 31.

  The chassis 21 is provided with a cleaning mechanism 60 as shown in FIG. The cleaning mechanism 60 includes a cap 61, a suction pump 62, and an ink discharge tube 63. Among these, the cap 61 is a portion that seals a nozzle forming surface (not shown) of the print head 33. When the suction pump 62 operates in this sealed state, the ink is discharged to a waste liquid tank (not shown) through the ink discharge tube 63. By this ink suction operation, a so-called cleaning operation for forcibly discharging bubbles mixed in the plate tube 500, the flexible tube 55, the print head 33, or the like can be executed.

  As shown in FIG. 2, the printer 10 is provided with a control unit 70. The control unit 70 includes an interface 71, a CPU (not shown), a memory, an ASIC (Application Specific Integrated Circuit), a bus, a timer, and the like. In addition, signals from various sensors are input to the control unit 70, and based on the signals from the sensors, a CR motor 34, a PF motor 41, a pump motor (not shown) of the pressure pump 53, suction It controls the pump motor (not shown) of the pump 62 and the drive of the print head 33 and the like.

  The printer 10 includes an interface 71. The printer 10 is connected to the computer 80 via the interface 71 (see FIG. 2). The computer 80 includes a CPU, RAM, ROM, HDD (Hard Disk Drive), interface, and the like (not shown). Among these, the HDD stores an application program for processing an image, a printer driver program, a video driver program, and the like.

<Details of plate tube configuration>
Then, the structure of the plate-shaped tube 500 which has the mechanism for pressure buffering is demonstrated based on FIG. 1, FIG. As shown in FIG. 1, in the present embodiment, two plate-like tubes 500, 500 are provided along the main scanning direction. Although these two plate-like tubes 500 and 500 have differences such as different lengths in the main scanning direction, their constituent elements are substantially the same. In the following description, they are collectively described as the plate-like tube 500. To do.

  These plate-like tubes 500 have a tube plate 510 and a film 560 as main components. Among these, the tube plate 510 is formed of a high-hardness (hard) resin material such as acrylic, for example. The film 560 is made of a thermoplastic resin such as polyethylene terephthalate or nylon. The film 560 is attached to the tube plate 510 by thermocompression bonding or the like. The film 560 may adopt a configuration in which a plurality of layers are stacked. In the case of adopting such a configuration, it is possible to employ a configuration in which a plurality of thermoplastic resin layers such as polypropylene or polyethylene are stacked on the above-described material so that water vapor does not pass through.

  Here, as shown in FIG. 5, the tube plate 510 has a holder mounting portion 520, a flow path forming portion 530, and a tube connecting portion 550. Among these, the holder attaching portion 520 is a portion that is attached and fixed to the cartridge holder 52, and in the present embodiment, the outer appearance is provided so as to form a substantially square shape in plan view. Through holes 521 are provided on the lower side of the holder mounting portion 520 by the number of ink cartridges 51 (three in this embodiment). An air tube 54 that pumps air from the pressurizing pump 53 is inserted into the through hole 521. Note that the air tube 54 communicates with the air chamber 51b of the ink cartridge 51, and can pump the air into the air chamber 51b to crush the ink pack 51c.

  In addition, an ink outflow hole 522 is provided above the through hole 521. The ink outflow hole 522 communicates with an ink supply needle 52 b provided in the cartridge holder 52. Here, when the ink cartridge 51 is mounted on the cartridge holder 52, the ink supply port 51d (see FIGS. 4 and 7) of the ink cartridge 51 and the ink supply needle 52b are connected, and the ink in the ink pack 51c is removed. The ink can flow out from the ink outflow hole 522. The ink outflow hole 522 serves as an inlet for allowing ink to flow into the pressure buffer chamber 523.

  The ink outflow hole 522 communicates with a staying recess 523 a that constitutes the pressure buffer chamber 523. As shown in FIGS. 7 and 8, the staying recess 523 a is a portion provided so as to be recessed from the other portions of the tube plate 510. Further, the staying recess 523a exists on the surface of the tube plate 510 opposite to the side on which the cartridge holder 52 is attached. In the following description, the surface of the tube plate 510 on which the cartridge holder 52 is attached is referred to as a back surface 510b (the surface on the side shown in FIG. 6) and the opposite surface (in FIG. 5). The surface on the side shown is a surface 510a.

  Further, as shown in FIGS. 5, 7, and 8, a flexible film 523b is attached so as to cover the staying recess 523a. The flexible film 523b and the staying recess 523a constitute a pressure buffer chamber 523. The flexible film 523b is attached to the surface 510a side of the tube plate 510. Further, the flexible film 523b bends in a direction away from the bottom of the staying recess 523a or bends toward the bottom of the staying recess 523a according to an internal pressure in a pressurizing chamber 524 described later.

  In addition, the retention recessed part 523a and the bending film 523b which comprise this pressure buffer chamber 523 respond | correspond to a volume fluctuation | variation means. The flexible film 523b corresponds to a flexible member and a film member.

  Moreover, as shown in FIG. 7 etc., the case body 524a is attached so that the above-mentioned pressure buffer chamber 523 may be covered. The case body 524a corresponds to a part of the pressurizing unit. The case body 524a has a box-like appearance with one side open. The case body 524a is attached and fixed in a state where the open side faces the surface 510a. This mounting and fixing is fixed to the surface 510a in a state where air flowing into the case body 524a does not leak to the outside. Thereby, the pressurization chamber 524 which covers the pressure buffer chamber 523 in a sealed state is configured. In addition, a tube insertion hole 524b is provided in a portion of the case body 524a that does not face the pressure buffering chamber 523 when viewed from the front (the lower side in FIG. 5). The tube insertion hole 524b is a hole through which the air tube 54 is inserted. The air tube 54 is inserted through the through hole 521 after inserting the tube insertion hole 524b.

  Further, the air tube 54 is provided with a communication hole 54 a that communicates with a pipe line of the air tube 54. The communication hole 54 a communicates with the pressurizing chamber 524. Therefore, when the pressurization pump 53 is operated to pump air, the pumped air is sent to the air chamber 51b side through the air tube 54 and also to the pressurization chamber 524. For this reason, the air chamber 51b and the pressurizing chamber 524 are maintained at substantially the same pressure (substantially equal pressure).

  Here, in a state where the ink cartridge 51 is mounted and ink is supplied toward the sub tank 56, the pressurizing pump 53 is operated and air is sent to the air chamber 51 b through the air tube 54. As a result, the ink pack 51c is crushed, and the ink flows out toward the plate-like tube 500 and flows into the pressure buffer chamber 523. Therefore, the internal pressure (hydraulic pressure) of the pressure buffer chamber 523 increases. However, in the operating state of the pressurizing pump 53, air is also supplied to the pressurizing chamber 524 via the air tube 54. For this reason, the internal pressure (air pressure) of the pressurizing chamber also increases. Therefore, the bending film 523b does not bend in the direction away from the bottom of the staying recess 523a but is substantially parallel to the surface 510a.

  Further, when the ink cartridge 51 is removed, the air tube 54 is opened to the atmosphere via the connection plug 54b, so that the pressurizing chamber 524 is opened to the atmosphere, and the internal pressure is reduced to the same state as the atmospheric pressure. On the other hand, on the flow channel side (flexible tube 55, plate-like tube 500, etc.) through which ink flows, the internal pressure is high before the ink cartridge 51 is removed, so the moment the ink cartridge 51 is removed. Due to the differential pressure between the internal pressure of the flow path and the pressurizing chamber 524 opened to the atmosphere, the flexible film 523b bends to the side away from the bottom of the retention recess 523a. Thereby, it is possible to prevent ink from being ejected from the ink supply needle 52b.

  Further, one end side of the through hole 525 is provided in the staying recess 523a. The through-hole 525 communicates with the staying recess 523a on the front surface 510a side, and communicates with the first groove portion 532a on the back surface 510b side (see FIG. 6). The first groove 532a constitutes the first ink flow path 532 by attaching the film 560 to the back surface 510b. Moreover, the 1st groove part 532a is extended toward the flow-path formation part 530 from the holder attaching part 520, as shown in FIG. The first groove 532a is formed in the vertical part 530a and the parallel part 530b of the flow path forming part 530.

  Here, in the parallel portion 530 b, each first groove portion 532 a is extended so as to be connected to each choke valve chamber 541. The first groove portion 532a is present on the back surface 510b, so that interference with the choke valve chamber 541 is avoided.

  An inflow hole 533 is provided at the downstream end of the first groove 532a. The inflow hole 533 passes through the parallel portion 530b, so that ink can be introduced into the ink introduction path 534 described below. In addition, this inflow hole 533 is located in the one end side (downward side) among the width directions of the parallel part 530b.

  Further, a total of three choke valve chambers 541 (refer to FIG. 5; corresponding to the liquid inflow chamber) and a portion for guiding ink to each choke valve chamber 541 through the inlet 542 are provided on the surface 510a side of the parallel portion 530b. And an ink introduction path 534. Of these, ink flows into the ink introduction path 534 from the inflow hole 533, and the other end side of the ink introduction path 534 is connected to the choke valve chamber 541 at the inflow port 542. The other end side of the ink introduction path 534 is located on the other end side (upper side) in the width direction of the parallel portion 530b.

  In addition, a discharge hole 543 is provided in a substantially central portion of the choke valve chamber 541. The discharge hole 543 extends from the bottom portion 541b of the choke valve chamber 541 toward the back surface 510b and penetrates the parallel portion 530b. The discharge hole 543 communicates with the second groove portion 535a on the back surface 510b side. Thus, the ink that has flowed into the choke valve chamber 541 can flow out toward the second groove portion 535a through the discharge hole 543. Further, a convex portion (not shown) is provided around the discharge hole 543 at the bottom of the choke valve chamber 541. This convex portion is a portion protruding from the bottom of the choke valve chamber 541 toward the surface side and projecting in a ring shape. The film 560 can be brought into and out of contact with the top side of the convex portion.

  The film 560 can be easily bent according to the pressure difference between the pressure in the choke valve chamber 541 and the pressure (on the outer side) opposite to the choke valve chamber 541 across the film 560. Here, when the choke valve chamber 541 becomes higher than the outside pressure, the film 560 bends toward the side away from the bottom of the choke valve chamber 541. In this case, a predetermined gap exists between the top of the convex portion and the film 560. Then, the ink can flow through the gap, and the ink can flow toward the discharge hole 543 (second groove portion 535a). Conversely, when the pressure on the outside becomes higher than the pressure in the choke valve chamber 541, the film 560 bends toward the side close to the bottom of the choke valve chamber 541. In this case, the film 560 contacts the entire circumference of the top of the convex portion without interruption. Accordingly, the ink does not flow out through the discharge hole 543 and the flow is blocked. In this way, the choke valve 540 can open and close the outflow of ink.

  The parallel portion 530b is provided with a second groove portion 535a. One end of the second groove portion 535a communicates with the discharge hole 543, and the other end portion communicates with the tube connection portion 550. The second groove portion 535a constitutes the second ink flow path 535 by attaching the film 560. The second groove portion 535a is provided on the back surface 510b side.

  Further, the tube connecting portion 550 is connected to the flexible tube 55. Here, the tube connection part 550 is provided with a pipe-like connection pipe 551, and the connection pipe 551 is inserted into the tube line of the flexible tube 55. And communicate.

<Operation related to ink supply of printer>
Hereinafter, an operation related to ink supply of the printer 10 will be described. Prior to ink supply, the user correctly attaches the ink cartridge 51 to the cartridge holder 52 and is ready to supply ink. And if the pressurization pump 53 act | operates by the instruction | command from the control part 70, air will be pumped through the air tube 54 and will be supplied to the air chamber 51b. In addition, since the communication hole 54a exists in the air tube 54, a part of the pressure-fed air is also supplied to the pressurizing chamber 524 through the communication hole 54a.

  Further, as described above, since the air is pumped to the air chamber 51b, the ink pack 51c is crushed by the pumping of the air. Then, the ink flows into the ink outflow hole 522 through the ink supply port 51d and the ink supply needle 52b. Thereafter, the ink is supplied to the sub tank 56 via the pressure buffer chamber 523, the first ink flow path 532, the choke valve chamber 541, the second ink flow path 535, the tube connection portion 550, and the flexible tube 55. .

  Further, as described above, when the supply of ink to the flow path existing up to the sub tank 56 is started, the internal pressure (hydraulic pressure) in the flow path rises above the atmospheric pressure. Therefore, the flexible film 523b constituting the pressure buffering chamber 523 also tries to bend in a direction away from the bottom of the retention recess 523a. However, the internal pressure (air pressure) of the pressurizing chamber 524 and the internal pressure (liquid) Pressure) varies depending on the operation of the same pressurizing pump 53, and these internal pressures are in a mutually corresponding relationship (in the present embodiment, substantially equal). Therefore, in the operating state of the pressurizing pump 53, the flexible film 523b is substantially parallel to the surface 510a as shown in FIG.

  By the way, for example, when the ink out is announced on the screen display of the computer 80 or the like, the user tries to replace the ink cartridge 51 that is out of ink. Then, the ink cartridge 51 is removed by the user. At this time, the connection state between the ink supply port 51d and the ink supply needle 52b is released, and the engagement (connection) between the tube engagement portion 51e and the connection plug 54b is also released.

  Here, on the flow channel side (flexible tube 55, plate-like tube 500, etc.) through which ink flows, the internal pressure in the flow channel is increased by the operation of the pressure pump 53 before the ink cartridge 51 is removed. It is in a state higher than atmospheric pressure. Therefore, at the moment when the ink cartridge 51 is removed, the elastic force such as expansion due to the internal pressure of the flexible tube 55 or the like formed of an elastic member or the like is released, and the flexible tube 55 is contracted by the elastic force or the like. Thus, the ink is about to be ejected from the ink supply needle 52b.

  However, when the ink cartridge 51 is removed, the air tube 54 is open to the atmosphere via the connection plug 54b. Therefore, the pressurizing chamber 524 is also opened to the atmosphere, and the internal pressure becomes the same as the atmospheric pressure. Therefore, as shown in FIG. 8, the ink which is going to the ink supply needle 52 b side causes the flexible film 523 b of the pressure buffer chamber 523 to be formed by the differential pressure between the internal pressure of the pressure chamber 524 and the internal pressure of the pressure buffer chamber 523. It is bent toward the direction away from the bottom of the retention recess 523a. At this time, the bending film 523b can be bent by an amount corresponding to the internal pressure (fluid pressure) in the flow path. Thereby, the volume (volume) inside the pressure buffer chamber 523 is increased, and the ink is absorbed by the increase in volume (volume) without being ejected from the ink supply needle 52b with a predetermined momentum.

<Effect when the present invention is applied>
According to the printer 10 described above, the pressure buffer chamber 523 is provided in the middle portion of the flow path through which the ink flows. In the ink supply state, the pressure chamber 524 is in a pressurized state, but when the ink cartridge 51 is removed, the pressure chamber 524 is opened to the atmosphere. Therefore, the internal volume (volume) of the pressure buffer chamber 523 increases due to the release from the pressurized state when the ink cartridge 51 is removed. As a result, even if the flow path is in a pressurized state and ink is about to be ejected from the ink supply needle 52b, the ejection can be suppressed by the increase in the internal volume (volume) described above. Thereby, when the ink cartridge 51 is removed, it is possible to prevent a problem that ink is ejected and the cartridge holder 52 and the print target P are soiled. Further, since it is possible to suppress the ejection of ink, it is not necessary to separately provide a portion for receiving the ejected ink, and an increase in cost can be suppressed.

  Moreover, in this Embodiment, the bending film 523b bends in the direction contacted / separated from the bottom part of the retention recessed part 523a according to an air pressure. Therefore, when the ink cartridge 51 is removed from the cartridge holder 52, the internal volume of the pressure buffer chamber 523 is easily increased by the bending of the flexible film 523b, and the ink pressure (hydraulic pressure) can be absorbed.

  Further, in the present embodiment, a pressurizing chamber 524 is formed by the case body 524a, and air pressurized from the pressurizing pump 53 is introduced into the pressurizing chamber 524 through the communication hole 54a. As a result, the inside of the pressurizing chamber 524 can be brought into a pressurized state, and in the ink supply state, the flexible film 523b can be maintained in a state of being pushed in from the pressurizing chamber 524 side. In other words, when the ink cartridge 51 is removed, the pressurizing state of the pressurizing chamber 524 is released, the pressing state of the deflecting film 523b due to pressurization cannot be maintained, and the direction in which the deflecting film 523b protrudes into the pressurizing chamber 524 Bend. As a result, the internal volume of the pressure buffer chamber 523 increases, and ink ejection can be prevented.

  The stay recess 523a is provided on the hard tube plate 510, and the flexure film 523b is a thin film member. For this reason, the bending film 523b can be easily bent according to the pressure (hydraulic pressure) of ink and the pressure (air pressure) of the pressurizing chamber 524. In addition, when the flexible film 523b is used, the flexible film 523b is easily bent. Therefore, no reaction force is exerted on the pressure buffer chamber 523 side due to the bending of the flexible film 523b. Therefore, when the flexible film 523b is bent toward the pressurizing chamber 524, it is possible to suppress an increase in pressure on the pressure buffer chamber 523 side.

  Further, the staying recess 523 a is provided in the plate-like tube 500 on the upstream side of the flexible tube 55. Here, since the flexible tube 55 has flexibility, the flexible tube 55 is flexible in the expanding direction by pressurization by the pressurization pump 53 or the like. Therefore, when the ink cartridge 51 is removed, the flexible tube 55 tends to contract due to the release of the pressurized state, and the ink flows upstream as the contraction occurs. However, since the retention recess 523a (pressure buffer chamber 523) is present on the upstream side of the flexible tube 55, the ink pressure (hydraulic pressure) can be absorbed. Thereby, when the ink cartridge 51 is removed, it is possible to prevent a problem that ink is ejected and the cartridge holder 52 and the print target P are soiled.

  Further, the pressure chamber 524 and the pressure buffer chamber 523 have substantially equal pressures when the pressure pump 53 is operated. For this reason, the bending film 523b can maintain an equilibrium state without being bent toward the pressurizing chamber 524.

<Modification of the present invention>
Although one embodiment of the present invention has been described above, the present invention can be variously modified in addition to this. This will be described below.

  In the above-described embodiment, the pressure buffer chamber 523 corresponding to the volume changing unit employs a configuration provided in the plate tube 500. However, the pressure buffer chamber 523 need not be provided in the plate-like tube 500. For example, the pressure buffer chamber 523 and the ink supply needle 52b are formed as one unit and can be attached to and detached from the ink outflow hole 522 of the plate-like tube 500. It may be configured. At this time, a bag-shaped member such as vinyl may be used as the pressure buffer chamber 523, and in this case, the flexible member corresponds to the bag-shaped member such as vinyl. At this time, the bag-like member corresponds to volume changing means.

  In the above-described embodiment, the case body 524a, the air tube 54, and the pressurizing pump 53 are used as the pressurizing means. However, the pressurizing means is not limited to these. For example, instead of the case body 524a, a bag-shaped member formed of vinyl or the like and communicated with the air tube 54 may be used so that the pressure buffer chamber 523 is covered with the bag-shaped member. A configuration in which the inside of the pressurizing chamber 524 is pressurized by using a pump separate from the pressurizing pump 53 may be used.

  In the above-described embodiment, the air tube 54 employs a configuration in which a part of the air flowing through the air tube 54 flows into the pressurizing chamber 524 through the communication hole 54a. However, a configuration in which all of the air pressure-fed from the air tube 54 is introduced into the pressurizing chamber 524 may be employed. In this case, for example, two air tubes may be used. When two air tubes are used, for example, one end side of the first air tube is connected to the pressurizing pump 53 and the other end side of the first air tube is connected to the pressurizing chamber 524. Further, one end side of the second air tube is connected to the pressurizing chamber 524, and a connection plug 54b that is engaged (connected) with the tube engaging portion 51e is provided on the other end side of the second air tube. To.

  In this way, the pressure from the pressurizing pump 53 is quickly applied to the pressurizing chamber 524, and when the air is released to the atmosphere, the air inside the pressurizing chamber 524 is more quickly supplied to the second air tube. It will be in the state which escapes from the other end side of this, and it becomes possible to open | release the pressurization chamber 524 to air | atmosphere earlier.

  Further, the printer 10 in the above-described embodiment may be a part of a complex device such as a configuration having functions (scanner function, copy function, etc.) other than the printer function. Further, the liquid ejection device is not limited to the printer 10. Examples of the liquid ejecting apparatus other than the printer 10 include a liquid ejecting apparatus used for manufacturing a liquid crystal display, an EL display, and the like. In addition, the liquid may be a liquid other than ink. For example, in a device for ejecting a liquid used for a liquid crystal display or an EL display, the color material and the electrode material are liquid.

1 is a perspective view illustrating a schematic configuration of a printer according to an embodiment of the present invention. It is a figure which shows schematic structure of the printer of FIG. FIG. 2 is a perspective view illustrating a configuration of a cartridge holder in the printer of FIG. 1. FIG. 2 is a perspective view illustrating a configuration of an ink cartridge in the printer of FIG. 1. It is a front view which shows the structure of the plate-shaped tube in the printer of FIG. It is a back view which shows the structure of the plate-shaped tube in the printer of FIG. It is sectional drawing which shows the structure of a pressure buffer chamber vicinity. It is sectional drawing which shows the state which the bending film has bent to the pressurization chamber side.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Printer, 30 ... Carriage mechanism, 31 ... Carriage, 33 ... Print head (corresponding to ejection head), 50 ... Ink supply mechanism, 51 ... Ink cartridge (corresponding to a part of liquid supply source and liquid storage means), 52 ... cartridge holder (corresponding to a part of the liquid supply source and mounting portion), 53 ... pressurizing pump (corresponding to a part of pressurizing means), 54 ... air tube (corresponding to a part of pressurizing means), 55 ... Flexible tube, 70 ... control unit, 80 ... computer, 500 ... plate tube, 510 ... tube plate, 510a ... front surface, 510b ... back surface, 520 ... holder mounting portion, 523 ... pressure buffer chamber (corresponding to volume variation means) ) 523a: staying recess (corresponding to a part of the volume changing means), 523b ... flexing film (corresponding to a part of the volume changing means, a deflecting member, a film member), 524 Pressurizing chamber (corresponding to pressurizing means), 524a ... Case body (corresponding to a part of the pressurizing means), 532 ... first ink channel, 535 ... second ink channel, 541 ... choke valve chamber, 550 ... Tube connection part, 560 ... film

Claims (7)

A discharge head for discharging liquid toward a discharge target;
A liquid supply source in which liquid storage means for storing the liquid therein is detachably attached to the mounting portion;
A flow path that communicates with the liquid storage means and distributes the liquid toward the liquid discharge head;
A volume changing means provided in the middle of the flow path, in which the liquid flows in and the internal volume changes according to the pressure;
An air pressure can be exerted on the volume variation means in a pressurized state, and when the liquid storage means is removed from the mounting portion, the pressure variation state on the volume variation means is released. Pressure means;
A liquid ejection apparatus comprising: The volume variation means is
A retention recess that is provided in the middle of the flow path and retains the liquid;
A pressure buffering chamber is formed by covering the staying recess in a state of being bent according to the pressure of the liquid, and is covered by the pressurizing means, and the staying according to the air pressure exerted by the pressurizing means A deflecting member that bends in a direction approaching or separating from the recess;
The liquid ejecting apparatus according to claim 1, further comprising: The pressurizing means is
A case body that forms a pressurizing chamber by covering the bending member in a state of closing from the outside,
Air is supplied to an air chamber provided in the liquid storage means, the communication chamber is provided with a communication hole that is inserted through the pressure chamber and communicates with the pressure chamber, and is opened to the atmosphere when the liquid storage means is removed. An air tube,
A pressurizing pump for pumping air to the pressurizing chamber and the air chamber via the air tube;
The liquid ejection apparatus according to claim 2, further comprising: The retention recess is provided in a hard resin member,
The liquid ejecting apparatus according to claim 2, wherein the flexible member is a thin film member. The flow path is
A flexible tube having a flexibility to be flexible according to the movement of the liquid ejection head, and a tube line for circulating the liquid;
A plate-like tube connected to the flexible tube and provided on the upstream side of the liquid supply from the flexible tube;
And having
The stay recess is provided in the plate tube,
The liquid discharge apparatus according to claim 2, wherein the liquid discharge apparatus is a liquid discharge apparatus.   The liquid ejecting apparatus according to claim 3, wherein the pressure chamber and the pressure buffer chamber have substantially equal pressures when the pressure pump is operated. A liquid supply method for supplying a liquid via a flow path from a liquid storage means detachably provided to a liquid supply source toward a liquid discharge head,
In the middle part of the flow path, the liquid flows in, and a volume changing means for changing the internal volume according to the pressure is provided,
When supplying the liquid from the liquid storage means toward the liquid ejection head, when applying air pressure to the volume variation means in a pressurized state and removing the liquid storage means from the liquid supply source Is the non-pressurized state of the volume variation means,
A liquid supply method.

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