JP2011245749A - Tube pump, and liquid ejection apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a tube pump and a liquid ejection apparatus, capable of strongly discharging a liquid from an opening having sucked the liquid.SOLUTION: The tube pump includes: a tube 65 having a base end opening 65a and a front end opening 65b, and also having at least an elastic intermediate part 62c in the length direction; a pump frame 63 having a supporting surface 63d for supporting the intermediate part 62c along its length direction; a pressing roller 77 rotatable about a drive axis 75; and an on-off valve 69 opening and closing the base end opening 65a. The pressing roller 77 rotates in the direction to approach to the front end opening 65b in the length direction of the tube 65 while crushing the intermediate part 62c in the tube 65 in the state of the on-off valve 69 being opened, and then also rotate in the direction to approach to the base end opening 65a in the length direction of the tube 65 while crushing the intermediate part 62c in the tube 65, by closing the on-off valve 69. Afterward, the on-off valve 69 is opened.

Description

  The present invention relates to a tube pump and a liquid ejecting apparatus capable of sucking and discharging a liquid.

  Conventionally, inkjet printers are widely known as one of liquid ejecting apparatuses. In this printer, printing is performed by ejecting ink (liquid) supplied from an ink cartridge (liquid supply source) from a nozzle formed in a recording head (liquid ejecting head) onto a recording medium as a target. Yes.

  In such a printer, recently, as described in Patent Document 1, for example, a contact member (pressing member) crushes a flexible tube arranged along a support surface having an arcuate cross section. However, a tube pump that sucks and discharges ink by circular motion is known.

  That is, in the case of the tube pump of Patent Document 1, the abutting member circularly moves in one direction so that ink is sucked from one end of the tube and ink is ejected from the other end of the tube.

JP 2004-137940 A

  By the way, in the case of the tube pump described in Patent Document 1, this liquid is in a state where the ink is filled up to a position where it is crushed by the contact member in the tube forming the ink flow path (liquid supply flow path). The ink is supplied to the downstream side of the ink flow path by being pressed under pressure. However, the liquid has a smaller volume change with respect to the pressure than the gas, and it is difficult to compress the ink in the tube. Therefore, it has been difficult to eject ink vigorously using the tube pump described in Patent Document 1. In a tube pump, there are cases where it is desired to perform both suction and discharge of ink from one end of the tube.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a tube pump and a liquid ejecting apparatus capable of ejecting liquid vigorously from an opening through which liquid has been sucked.

  In order to achieve the above object, the tube pump of the present invention is provided with an opening on one end side that enables suction and discharge of liquid on one end side in the length direction and air on the other end side in the length direction. A tube having an opening at the other end that is open with respect to the tube and having at least an intermediate portion in the length direction having elasticity, and an arc-shaped support that can support the intermediate portion of the tube along the length direction A pressing member that is capable of circular movement about an axis that is a center of an arc of the support surface so as to close the internal space of the tube between the pump frame having a surface and the support surface; and the one end side opening. An opening / closing valve that can be closed, and the pressing member approaches the other end side opening in the length direction of the tube while crushing the intermediate portion of the tube with the opening / closing valve opened. After the circular movement in the direction, the open / close valve is closed and the intermediate portion of the tube is crushed while the tube is circularly moved in the direction approaching the one end side opening in the length direction of the tube. Is opened.

  According to this configuration, the liquid can be sucked from the one end side opening, and the sucked liquid can be ejected vigorously from the one end side opening. That is, when the pressing member moves circularly in the direction of approaching the other end side opening in the length direction of the tube with the on-off valve opened, the inner space on the one end opening side of the tube is crushed. Since the volume increases to a negative pressure, the liquid is sucked from the one end opening. Also. When the pressing member moves circularly in a direction approaching the one end side opening with the on-off valve closed, the volume decreases in the internal space on the one end opening side of the crushed position in the tube. The gas in the space is compressed. Therefore, when the on-off valve is opened, the liquid is vigorously discharged from the one end side opening based on the pressure of the compressed gas. Accordingly, the liquid can be ejected vigorously from the opening on the one end side that has sucked the liquid.

  In the tube pump according to the aspect of the invention, the pump frame includes a cutout portion in which a part of the support surface is cut out in a circumferential direction centering on the axis, and the pressing member is formed with respect to the support surface. A closed section in which the inner space of the tube is closed by pressing the tube and a non-closed section in which the pressing member is not in the notch are positioned on the circular motion locus of the pressing member.

  According to this configuration, since the closed section and the non-closed section are positioned on the circular motion trajectory of the pressing member, the pressing member can be positioned in the closed section and the non-closed section with the circular motion. . Further, when the pressing member is located in the non-blocking section, the blocking of the tube is released and the internal space is opened to the atmosphere. Therefore, the pressure in the internal space of the tube can be easily adjusted by the amount of movement of the pressing member from the non-occluding section.

The tube pump of the present invention further includes control means for controlling movement of the on-off valve and the pressing member.
According to this configuration, the on-off valve is opened and closed according to the control of the control means, and the pressing member moves, so that the suction and discharge of the liquid from the one end side opening can be easily changed.

  In the tube pump of the present invention, an intermediate opening that opens an internal space of the tube to the atmosphere between the intermediate portion in the length direction of the tube and the on-off valve, and the intermediate opening And an air release valve that can be closed by a valve closing operation based on the control of the control means.

  According to this configuration, it is possible to change the momentum of the ejected liquid when ejecting the liquid from the one end side opening. That is, for example, the air release valve is opened and the pressing member is displaced in a direction approaching the one end side opening. Then, since the volume decreases in the internal space closer to the one end side opening than the position pressed by the pressing member, gas is discharged from the intermediate opening. When the air release valve is closed and the pressing member is further displaced in the direction approaching the one end side opening, the volume of the internal space on the one end side opening side than the crushed position in the tube decreases. Thus, the gas in the internal space is compressed. That is, the pressure in the internal space at this time is smaller than when the air release valve is closed when the pressing member starts to be displaced. Therefore, for example, even when the pressing member is circularly moved by a certain amount, the moment when the liquid is discharged from the one end side opening can be easily changed by changing the timing of opening and closing the atmosphere release valve. Can do.

  The tube pump according to the present invention further includes detection means for detecting the presence or absence of liquid in the internal space of the tube between the on-off valve and the intermediate portion in the length direction of the tube, and the control means includes When the liquid is sucked into the internal space of the tube from the opening on the one end side and the detection means detects the liquid, the on-off valve is closed.

  According to this configuration, when the liquid is sucked into the internal space of the tube, and the detection means detects the liquid, the control means restricts the movement of the liquid by closing the on-off valve. Can do. That is, since the liquid moves closer to the opening on the one end side than the detection means, it is possible to reduce the possibility of the liquid leaking from the opening on the other end side.

  In the tube pump of the present invention, the tube further includes a plurality of branch portions that branch at a branch point between the detection means and the intermediate portion in the length direction thereof and communicate with the internal space, and the branch portions. Each has the one end side opening, the on-off valve, and the detection means.

  According to this configuration, the liquid can be sucked and discharged for each of the plurality of one-end openings by the displacement of one pressing member. That is, the internal space of each branch part is in communication, and an open / close valve is provided in each branch part. Therefore, for example, by opening one on-off valve in a state where the gas on the branch point side is compressed from the position where the pressing member is closed, it is selectively selected from one end-side opening corresponding to the opened on-off valve. Liquid can be discharged. In addition, by providing the detection means at each branch portion, it is possible to suppress the intrusion of the liquid to the branch point side than the detection means. Therefore, even if it is a case where a different kind of liquid is attracted | sucked from each one end side opening part, mixing of liquids can be suppressed.

  The liquid ejecting apparatus of the present invention includes a liquid ejecting head that ejects liquid to a target, and a liquid supply flow that supplies the liquid from an upstream side that is a liquid supply source side to a downstream side that is the liquid ejecting head side. A one-way valve provided at a first position in the liquid supply flow path and allowing the liquid to pass from the upstream side to the downstream side, and downstream from the first position in the liquid supply flow path. A tube pump configured as described above, wherein the liquid can be sucked and discharged from the second position by connecting the opening on the one end side to the second position on the side.

  According to this configuration, since the liquid can be ejected vigorously from the tube pump, for example, a mechanism for applying a negative pressure from the liquid ejecting head side becomes unnecessary, and the liquid ejecting apparatus can be downsized.

1 is a schematic diagram of a printer according to an embodiment. FIG. 2 is a schematic diagram of an ink supply system. The schematic diagram of the maintenance pump at the time of suction drive. The schematic diagram of the maintenance pump at the time of suction drive. The schematic diagram of the maintenance pump at the time of suction drive. The schematic diagram of the maintenance pump at the time of suction drive. The schematic diagram of the maintenance pump at the time of discharge drive. The schematic diagram of the maintenance pump at the time of discharge drive. Schematic diagram of maintenance pump during cleaning. Schematic diagram of maintenance pump during cleaning. Schematic diagram of maintenance pump during cleaning. The schematic diagram of the maintenance pump of 2nd Embodiment. Schematic diagram of maintenance pump during cleaning. Schematic diagram of maintenance pump during cleaning. Schematic diagram of maintenance pump during cleaning.

(First embodiment)
Hereinafter, a first embodiment in which a liquid ejecting apparatus of the invention is embodied in an ink jet printer will be described with reference to FIGS. In the following description, the terms “left-right direction” and “up-down direction” refer to the left-right direction indicated by arrows in FIG. Further, when referring to the “front-rear direction”, the direction orthogonal to the paper surface of FIG.

  As shown in FIG. 1, an ink jet printer (hereinafter referred to as “printer”) 11 as a liquid ejecting apparatus includes a transport unit 13 for transporting a sheet 12 as a target, and a printing for printing on the sheet 12. And a recording head unit 15.

  The transport unit 13 includes a rectangular plate-shaped platen 17 that is long in the left-right direction. A drive roller 18 extending in the front-rear direction is disposed on the right side of the platen 17 so as to be rotationally driven by a drive motor 19, while a driven roller 20 extending in the front-rear direction is disposed on the left side of the platen 17 so as to be rotatable. Further, a tension roller 21 extending in the front-rear direction is rotatably disposed below the platen 17.

  An endless transport belt 22 having a large number of through holes is wound around the drive roller 18, the driven roller 20, and the tension roller 21 so as to surround the platen 17. In this case, the tension roller 21 is urged downward by a spring member (not shown), and by applying tension to the conveyor belt 22, looseness of the conveyor belt 22 is suppressed.

  Then, when the driving roller 18 is rotationally driven in the clockwise direction when viewed from the front side, the conveying belt 22 is rotated in the clockwise direction when the outer side of the driving roller 18, the tension roller 21, and the driven roller 20 is viewed from the front side. It has become. Further, when the sheet 12 is at a position facing the upper surface of the platen 17, the sheet 12 is sucked to the platen 17 side through the conveying belt 22 by a suction unit (not shown), and is conveyed from the upstream left side to the downstream right side. It has come to be.

  A pair of upper and lower paper feed rollers 23 for feeding a plurality of unprinted paper sheets 12 one by one onto the transport belt 22 one by one is provided on the upper left side of the driven roller 20. On the other hand, on the diagonally upper right side of the driving roller 18, a pair of upper and lower paper discharge rollers 24 for discharging the printed paper 12 one by one from the transport belt 22 are provided.

  As shown in FIGS. 1 and 2, the recording head unit 15 includes a plurality of (four in the present embodiment) recording heads 26 to 29 extending in the front-rear direction and spaced in the left-right direction. Is provided. In addition, on the nozzle formation surfaces 26a to 29a that are the lower surfaces of the recording heads 26 to 29, a large number of nozzles 30 are regularly formed at predetermined intervals in the front-rear direction so as to form nozzle rows along the front-rear direction. It is open. The nozzles 30 thus configured are supplied with the same type of ink (liquid) for each of the recording heads 26 to 29 and ejected from the nozzles 30.

  That is, as shown in FIG. 2, the first recording head 26 receives black ink from an ink cartridge 31 serving as a liquid supply source containing black ink via an ink flow path 32 serving as a liquid supply flow path. Is connected to the ink supply device 33. Similarly, the second to fourth recording heads 27 to 29 are connected to an ink supply device 33 that supplies ink from ink cartridges 31 containing inks of cyan, magenta, and yellow, respectively.

  However, since the configuration of the ink supply device 33 that supplies ink from each ink cartridge 31 to each recording head 26 to 29 is the same, FIG. 2 shows one ink supply device that supplies ink to the first recording head 26. Only 33 is shown together with the first recording head 26 and the ink cartridge 31. In the following description, the first recording head 26 and the ink supply device 33 that supplies ink to the first recording head 26 shown in FIG. 2 will be described as an example.

  As shown in FIG. 2, a reservoir 36 communicating with the downstream side of the ink flow path 32 is formed in the first recording head 26 so as to extend in the front-rear direction along the nozzle row. A plurality of branch flow paths 35 individually corresponding to the nozzles 30 are branched from a plurality of positions in the extending direction. The branch channel 35 includes a cavity 37 that communicates with the nozzle 30, and a communication channel 38 that communicates the cavity 37 and the reservoir 36. Further, a piezoelectric element (not shown) is disposed at a position adjacent to the cavity 37 in the first recording head 26. The piezoelectric element contracts and expands to change the volume of the cavity 37, so that ink is ejected from the nozzle 30.

  The ink cartridge 31 includes a flexible ink pack 46 that stores ink, and a case 47 that stores the ink pack 46. In addition, a pressure pump 49 is connected to the case 47 via an air flow path 48, and an upstream end of the ink flow path 32 is connected to the ink pack 46. The pressure pump 49 supplies air into the case 47 via the air flow path 48 so that the ink pack 46 is crushed and the ink in the ink pack 46 is supplied to the ink flow path 32. It has become.

  In addition, the pressure adjustment position PT as the first position in the ink flow path 32 allows the ink to pass from the upstream side to the downstream side as the downstream pressure decreases, and adjusts the pressure in the ink flow path 32. A one-way valve 51 is provided. In other words, the one-way valve 51 includes a storage chamber 52 that primarily stores ink pressurized and supplied from the ink cartridge 31, and a pressure chamber 53 that is positioned downstream of the storage chamber 52. The storage chamber 52 and the pressure chamber 53 are separated by a partition wall portion 54, and a valve hole 54 a is formed through the partition wall portion 54. A valve body 56 that is urged in the valve closing direction by the spring 55 and contacts the partition wall portion 54 from the storage chamber 52 side is disposed in the valve hole 54 a, and the valve body 56 resists the urging force of the spring 55. Accordingly, the storage chamber 52 and the pressure chamber 53 communicate with each other by moving in the valve opening direction.

  That is, when ink is ejected from the nozzle 30 and consumed, the pressure chamber 53 is depressurized, and the film 57 is bent and deformed toward the pressure chamber 53 based on the pressure difference between the pressure chamber 53 and the atmosphere. When the bending force becomes larger than the urging force of the spring 55, the valve body 56 moves to the valve opening position away from the partition wall 54, and the pressurized ink in the storage chamber 52 flows into the pressure chamber 53 side. . When ink flows into the pressure chamber 53 and the chamber pressure is increased, the urging force of the spring 55 is overcome and the valve body 56 is moved again to the valve closing position where it abuts against the partition wall portion 54.

  As described above, the one-way valve 51 is opened by the pressure reduction on the downstream side of the valve body 56, whereas when the upstream side is pressurized, the valve body 56 receives a force in the closing direction, so that the valve is opened. Keep valve closed without valve. Similarly, when the downstream side is pressurized, the film 57 bends and deforms in the direction of increasing the volume of the pressure chamber 53, so that the valve body 56 closes without receiving a force in the valve opening direction from the film 57. Maintain valve status. Furthermore, since the upstream ink is pressurized by the pressurizing pump 49, the upstream side of the valve body 56 is not depressurized. That is, the one-way valve 51 is a valve that opens only when the downstream side is depressurized.

  A part of the pressure chamber 53 is constituted by a film 57 made of a flexible material (for example, synthetic resin or rubber). For example, a cantilever metal piece (for example, comb teeth) that can be displaced together with the film 57 is used. A piece of metal piece) is arranged at the contact point of the valve body 56.

  A maintenance pump 61 as a tube pump capable of sucking and discharging ink by changing the pressure in the ink flow path 32 is provided at a transformation position PH as a second position downstream of the pressure adjustment position PT. It is connected.

  The maintenance pump 61 is a pump that can pressurize the ink in the recording head 26. That is, although the pressurizing pump 49 is provided separately from the maintenance pump 61, pressurization by the pressurizing pump 49 is blocked by the one-way valve 51, and the pressurizing force cannot be transmitted to the recording head 26. Therefore, in order to perform maintenance of the recording head 26, a maintenance pump 61 capable of pressurizing the ink in the recording head 26 is required in addition to the pressurizing pump 49.

  As shown in FIG. 3, the maintenance pump 61 is capable of pressing the elastic portion 62, a cylindrical elastic portion 62 having both ends opened in the length direction and having elasticity, a frame 63 that supports the elastic portion 62, and the elastic portion 62. And a pressing mechanism 64.

  The frame 63 has a base end support portion 63a, a tip support portion 63b, and an intermediate support portion 63c that support the base end portion 62a and the tip end portion 62b of the elastic portion 62, and the intermediate portion 62c in the length direction. Yes. The base end support portion 63 a in the frame 63 is formed in a cylindrical shape, and the base end side portion is connected to the ink flow path 32. The proximal end portion 62a of the elastic portion 62 is connected to the distal end side portion of the proximal end support portion 63a, and the tube 65 is configured by the elastic portion 62 and the proximal end support portion 63a that communicate with the internal space.

  In addition, the tip support portion 63b of the frame 63 is formed in a cylindrical shape so as to support the tip portion 62b of the elastic portion 62 in an inserted state. Furthermore, the intermediate support part 63c in the frame 63 is a plate-like body that connects the base end support part 63a and the front end support part 63b, and supports the elastic part 62 from the outer peripheral side in a curved state. Thus, the cross section is formed into an arc shape. That is, the intermediate support part 63c is cut out in a circumferential direction centered on the arc center of the support surface 63d, which is an inner surface of the intermediate support part 63c, with a part of the ring being cut out to form a C-shaped cross section. The cut portion is a notch 63e. And the intermediate part 62c of the elastic part 62 is supported along the length direction by the support surface 63d of the intermediate | middle support part 63c as a pump frame curved in the circular arc shape of the cross section.

  In addition, the base end support portion 63a of the frame 63 has a plurality of branch portions 66 branched from the branch point Pb. Note that the number of branching portions 66 is the same as the number of types of ink ejected in the printer 11 (four in this embodiment). However, since the structure of each branch part 66 is the same, only the 1st branch part 66a and the 2nd branch part 66b are illustrated in FIG. 3, and the 1st branch part is shown in FIGS. Only 66a is illustrated. In the present embodiment, the first branch portion 66a and the connection portion 67 are branched from the branch point Pb, and the second branch portion 66b and the third and fourth branch portions ( (Not shown) are connected. Therefore, the internal spaces communicate with each other through the connecting portion 67.

  As shown in FIG. 3, the base end side end portion (one end side in the length direction of the tube 65) of each branch portion 66 is a base end opening portion as one end side opening portion capable of sucking and discharging ink. 65a, which is connected to each ink flow path 32. In other words, the first branch portion 66 a has a proximal end opening 65 a connected to the first ink flow path 32 a connected to the first recording head 26. In addition, the second branch portion 66 b has a proximal end opening portion 65 a connected to the second ink flow path 32 b connected to the second recording head 27. Similarly, the third and fourth branch portions (not shown) are connected to third and fourth ink flow paths (not shown) connected to the third and fourth recording heads 28 and 29, respectively. Yes.

  Further, on each branching portion 66, a position close to the base end opening 65a is provided with an opening / closing valve 69 that can block the base end opening 65a and restrict the flow of ink. Further, a sensor as a detection means capable of detecting the presence or absence of ink sucked into the internal space of each branch portion 66 at a position closer to the tip side than the on-off valve 69 in each branch portion 66 (66a, 66b...). 70 is provided. Specifically, in the case of the first branch portion 66a, the tube 65 is positioned at a position between the branch point Pb and the on-off valve 69 in the length direction of the tube 65, and in the case of the second branch portion 66b, the tube Sensors 70 are provided at positions between the connection portion 67 and the on-off valve 69 in the length direction 65.

  In each branch portion 66, the volume of the internal space between the on-off valve 69 and the sensor 70 is larger than the volume of the internal space in the intermediate portion 62c of the elastic portion 62. However, the cross-sectional area (for example, 1 mm in diameter) of the portion where the on-off valve 69 is provided in each branching portion 66 is smaller than the cross-sectional area of the other portion in the length direction (for example, 3 mm in diameter).

  Further, the end portion on the distal end side of the elastic portion 62 (the other end side in the length direction of the tube 65) is a distal end opening portion 65b as the other end side opening portion that opens the internal space of the tube 65 to the atmosphere. ing.

  Further, in the length direction of the tube 65, a cylindrical portion 72 extending upward in the gravitational direction is provided at a position closer to the proximal end than the intermediate portion 62c of the elastic portion 62 and closer to the distal end than the sensor 70. Is formed. The cylindrical portion 72 is provided with an intermediate opening 65c that opens the internal space of the tube 65 to the atmosphere, and an atmospheric release valve 73 that can close the intermediate opening 65c.

  Note that the portion of the tube 65 from the proximal end opening 65a to the intermediate portion 62c of the elastic portion 62 is such that the proximal end opening 65a is positioned below the intermediate portion 62c in the direction of gravity. It is provided to extend obliquely upward from 65a. And in the tube 65, the front-end | tip opening part 65b is provided so that it may be located in a gravity position rather than the base end opening part 65a.

  As shown in FIGS. 3 and 4, a pressing mechanism is provided at the inner (inner peripheral side) position of the intermediate portion 62 c of the elastic portion 62 supported in an arcuate shape by the intermediate support portion 63 c of the frame 63. 64 is arranged. The pressing mechanism 64 is rotatably provided at a rotary plate 76 that can rotate around a drive shaft 75 that is the center of the arc of the support surface 63d, and a tip portion of a tongue piece 76a that protrudes radially outward of the rotary plate 76. And a pressing roller 77 as a pressing member. The pressing roller 77 is provided so as to be rotatable about a rotation shaft 78. And the press roller 77 is comprised so that the intermediate part 62c of the elastic part 62 may be pressed toward the intermediate support part 63c side of the frame 63 from the inner peripheral side at the time of the rotation. That is, the pressing roller 77 is disposed so as to squeeze and crush the elastic portion 62 with the support surface 63d of the intermediate support portion 63c.

  Therefore, the tube 65 (specifically, the intermediate portion 62c of the elastic portion 62) has a proximal end opening at the pressing point 62d that is a position crushed by the pressing roller 77 and the intermediate support portion 63c of the frame 63. An inner space on the base end side that is the portion 65 a side is an ink chamber 79. Further, the inner space on the distal end side closer to the distal end opening 65b than the pressing point 62d is a gas chamber 80.

  Then, when the drive shaft 75 rotates forward in accordance with the forward rotation drive of the pressing motor 81 (see FIG. 2), the pressing roller 77 together with the rotating plate 76 in the direction indicated by the white arrow in FIG. 3 (counterclockwise direction). It is designed to make a circular motion. That is, if the pressing roller 77 moves circularly in a direction approaching the tip opening 65b while maintaining the state where the elastic portion 62 is crushed, the volume of the ink chamber 79 increases and the gas chamber is increased as shown in FIG. The pressing point 62d moves in the direction in which the volume of 80 decreases.

  Further, when the pressing roller 77 further circularly moves from the suction end position P2 shown in FIG. 5 and is positioned in a non-clamping area A (see FIG. 3) as a non-blocking section with respect to the notch 63e shown in FIG. Is released, and the ink chamber 79 and the gas chamber 80 communicate with each other. That is, the non-clamping region A is a position where the pressing roller 77 is not opposed to the intermediate support part 63c, and is a position where the intermediate part 62c of the elastic part 62 cannot be clamped between the intermediate support part 63c.

  When the pressing roller 77 further moves in a circular motion and moves to the clamping region B (see FIG. 3) as a closed section where the elastic portion 62 can be clamped together with the intermediate support portion 63c, the pressing roller 77 is moved as shown in FIG. The elastic part 62 is pressed against the intermediate support part 63c and sandwiched. That is, the clamping region B is a position where the pressing roller 77 is opposed to the intermediate support part 63c via the intermediate part 62c of the elastic part 62, and is a position where the intermediate part 62c can be pressed and pressed against the intermediate support part 63c side. is there.

  In this embodiment, one non-clamping area A and one clamping area B are positioned on the circular motion locus of the pressing roller 77, and the clamping area B is centered around the drive shaft 75 rather than the non-clamping area A. The region length in the circumferential direction is long.

  Further, as shown in FIG. 2, the printer 11 is provided with a control unit 82 as a control unit that performs overall control of the operating state of the printer 11. The control unit 82 drives and controls the piezoelectric elements (not shown), the pressure pump 49, the maintenance pump 61, and the pressing motor 81 provided in each of the recording heads 26 to 29, and performs initial ink filling, printing, and cleaning processing. Is supposed to do. As shown in FIG. 4, the control of the maintenance pump 61 is the open / close control of each open / close valve 69 and the atmosphere open valve 73 based on the detection result of the sensor 70 provided in each branch portion 66.

  Next, the operation of the printer 11 configured as described above will be described below. In the drawing, the open valve of the on-off valve 69 and the air release valve 73 is shown in white, and the valve in the closed state is shown in black.

  When the ink cartridge 31 is mounted on the printer 11 for the first time, the control unit 82 controls the drive of the maintenance pump 61 to perform the initial filling process. In the printer 11 before the initial filling, since the ink flow path 32 is not filled with ink, when the maintenance pump 61 is driven to suck, air (gas and fluid) is sucked. Further, it is assumed that the pressing roller 77 is located at the suction start position P1 (see FIG. 3).

  First, the control unit 82 opens the on-off valve 69 and drives the pressing motor 81 to rotate forward with the air release valve 73 closed. Then, since the pressing roller 77 moves circularly from the suction start position P1 in a direction approaching the distal end opening 65b in the length direction of the tube 65, the ink chamber 79 in which the volume increases is inserted through the proximal end opening 65a. Air is sucked from the ink flow path 32 (suction drive).

  On the other hand, the volume in the gas chamber 80 decreases, and the air (gas and fluid) in the gas chamber 80 is discharged from the tip opening 65b, whereby the gas chamber 80 is maintained in an atmospheric pressure state. Therefore, even if the pressure roller 77 further moves circularly from the suction end position P2 (see FIG. 5) and moves to the non-nipping region A (see FIG. 6), and the ink chamber 79 and the gas chamber 80 communicate with each other, the ink chamber Within 79, no pressure change occurs. Therefore, no air is discharged from the proximal end opening 65a.

  Further, when the pressing motor 81 is driven and the pressing roller 77 moves circularly (for example, twice), the inside of the ink flow path 32 becomes negative pressure. In the recording head 26 to which the ink flow path 32 is connected, the flow path resistance is large and the air sucked from the nozzles 30 is limited. Therefore, when negative pressure acts on the one-way valve 51 and the one-way valve 51 is opened, ink is sucked into the maintenance pump 61 from the ink cartridge 31 side.

  Then, as shown in FIG. 3, when the pressure roller 77 located at the suction start position P1 further moves circularly and moves to the position shown in FIG. 4, for example, when the sensor 70 detects ink, the controller 82 opens and closes. The valve 69 is closed and the atmosphere release valve 73 is opened.

  Therefore, as shown in FIG. 5, even if the pressing roller 77 further moves circularly, the on-off valve 69 is closed, so that the ink suction from the ink flow path 32 is restricted and the ink level is detected by the sensor. It is located near 70. Further, since air is sucked into the ink chamber 79 whose volume increases from the intermediate opening 65c, the space in the ink chamber 79 that is closer to the pressing point 62d than the ink surface is in an atmospheric pressure state. Therefore, as shown in FIG. 6, even when the pressing roller 77 moves to the non-clamping area A, ink is not ejected from the base end opening 65a, and the ink level is located in the vicinity of the sensor 70. .

  When the ink is sucked up to the sensor 70, the control unit 82 causes the maintenance pump 61 to alternately perform discharge driving and suction driving. That is, as shown in FIG. 7, the control unit 82 drives the pressing motor 81 in the reverse direction with all the opening / closing valves 69 and the atmosphere opening valves 73 closed, and the direction indicated by the white arrows (clockwise). Make a circular motion in the rotation direction).

Then, in the ink chamber 79 whose volume decreases, the air in the ink chamber 79 is compressed, whereas in the gas chamber 80 whose volume increases, air is sucked from the tip opening 65b.
Then, as shown in FIG. 8, when the pressing roller 77 moves to the suction start position P1, the control unit 82 opens the on-off valve 69. Then, the ink (liquid and fluid) in the ink chamber 79 whose pressure has increased is discharged from the base end opening 65a to the ink flow path 32, and the maintenance pump 61 is driven to discharge.

  In the tube 65, the volume of the internal space between the on-off valve 69 and the sensor 70 is larger than the volume of the internal space of the portion that can be pressed by the pressing roller 77 of the intermediate portion 62c of the elastic portion 62. Therefore, the opening / closing valve 69 divides the ink in the internal space (ink chamber 79) of the tube 65, and the liquid level of the ink after being driven to discharge is more in the length direction of the tube 65 than the opening / closing valve 69. Located on the distal end side, air discharge from the proximal opening 65a is suppressed.

  By the way, in the ink flow path 32, the one-way valve 51 provided on the upstream side from the transformation position PH opens when the pressure is reduced from the downstream side, whereas when the pressure is applied from the downstream side. Keep the valve closed. For this reason, when ink is discharged from the maintenance pump 61, the one-way valve 51 is closed, so that the ink is vigorously supplied to the recording head 26 side, which is downstream of the pressure adjustment position PT. Therefore, ink is filled into the ink flow path 32 and the recording head 26 by repeating the suction drive and the discharge drive of the maintenance pump 61 (initial filling process).

  When printing is started in the printer 11 that has been subjected to the initial filling process as described above, the control unit 82 creates the ink ejection timing for each nozzle 30 based on the print data, and the ejection. The piezoelectric element is driven based on the timing, and ink is ejected from the nozzle 30. In other words, the ink ejected from each nozzle 30 adheres to the paper 12 supported by the transport belt 22 and transported, whereby the paper 12 is printed.

  When ink is ejected from the nozzle 30 and consumed, the reduced pressure accompanying the decrease in ink is transmitted to the one-way valve 51 via the reservoir 36 and the ink flow path 32. Then, the valve body 56 moves to the valve opening position against the urging force of the spring 55, and the ink in the storage chamber 52 flows into the pressure chamber 53 side. When ink flows into the pressure chamber 53 and the chamber pressure increases, the urging force of the spring 55 overcomes and the valve body 56 moves to the valve closing position again.

  Accordingly, since the one-way valve 51 allows ink to pass from the upstream side to the downstream side in accordance with the pressure reduction on the downstream side, the consumed ink is supplied from the ink cartridge 31 side.

  By the way, if the period during which ink is not ejected from the nozzles 30 without printing is increased, the ink may evaporate from the nozzles 30 to increase the viscosity of the ink, or the meniscus position may increase. The rise in the meniscus position may occur not only in the evaporation of ink but also in other situations such as when the printer 11 receives an impact or when the end of the paper 12 contacts the nozzle 30.

  Therefore, the control unit 82 executes the cleaning process when, for example, a cleaning process execution command is received from a user (not shown) from the user or when it is determined that a predetermined time has passed since the previous cleaning process. It is assumed that the maintenance pump 61 is driven to suck the ink to the sensor 70, and the pressing roller 77 is positioned at the suction end position P2.

  Now, as shown in FIG. 9, the controller 82 first closes the on-off valve 69, drives the pressure motor 81 in the reverse direction with the air release valve 73 opened, and presses the pressure roller 77 with a white arrow. Make a circular motion in the direction shown (clockwise). Then, in the ink chamber 79 in which the volume decreases, air is discharged from the intermediate opening 65c, whereas in the gas chamber 80 in which the volume increases, air is sucked from the tip opening 65b.

  Further, as shown in FIG. 10, the control unit 82 closes the air release valve 73 during the movement from the suction end position P2 to the suction start position P1. Note that the timing for switching the opening and closing of the atmosphere release valve 73 is changed according to the pressure applied when ink is ejected, and the timing is switched closer to the suction end position P2 as ink is ejected more vigorously. When the pressing roller 77 further moves, the stored air is compressed in the ink chamber 79 whose volume decreases.

  As shown in FIG. 11, when the pressing roller 77 moves to the suction start position P1, the control unit 82 corresponds to the branching unit 66 (for example, corresponding to the first recording head 26) corresponding to the recording head that performs cleaning. The on-off valve 69 of the first branch part 66a) is opened. Then, the ink in the ink chamber 79 whose pressure is increasing is ejected vigorously from the proximal end opening 65 a to the ink flow path 32.

  Note that when the maintenance pump 61 is driven to discharge, the one-way valve 51 maintains the closed state, so that the ink discharged from the maintenance pump 61 vigorously moves to the recording head 26 side downstream of the pressure adjustment position PT. Supplied.

  Therefore, when the maintenance pump 61 ejects ink, the ink having increased viscosity near the nozzle opening or the ink mixed with bubbles is discharged together with the ink supplied from the maintenance pump 61 side, and the recording head 26 is cleaned.

  Further, the controller 82 opens the on-off valve 69 and closes the on-off valve 69 when the valve opening time corresponding to the amount of ink to be discharged has elapsed. That is, for example, when there are a large number of poorly ejected nozzles 30 and strong cleaning is performed, the amount of ink ejected is large. Therefore, the valve opening time becomes longer than when weak cleaning is performed with a small amount of ejected ink. In addition, since the cross-sectional area of the tube 65 in the vicinity of the opening / closing valve 69 is smaller than the cross-sectional area of other portions in the length direction, the flow rate when ink is ejected is limited, and the adjustment of the amount of ink ejected becomes easy. ing.

  When the on-off valve 69 is closed, the control unit 82 further drives the pressing motor 81 in the reverse direction to move the pressing roller 77 to the non-nipping region A. Then, the ink chamber 79 and the gas chamber 80 communicate with each other and are released to the atmosphere, and the pressurization in the ink chamber 79 is released. Thereafter, the control unit 82 maintains the closed state of the atmosphere release valve 73 and opens the on-off valve 69. Further, the control unit 82 drives the pressing motor 81 to rotate in the forward direction and causes the pressing roller 77 to circularly move toward the distal end side in the length direction of the tube 65, whereby ink is sucked again from the proximal end opening 65a. The

According to the first embodiment, the following effects can be obtained.
(1) While sucking ink from the base end opening 65a, the sucked ink can be ejected vigorously from the base end opening 65a. That is, for example, the on-off valve 69 is opened, and the pressing roller 77 moves circularly in a direction approaching the tip opening 65b in the length direction of the tube 65. Then, the volume of the ink chamber 79 in the tube 65 is increased to a negative pressure, so that the ink is sucked from the proximal end opening 65a. Also. When the opening / closing valve 69 is closed and the pressing roller 77 is moved circularly in the direction approaching the proximal end opening 65a, the volume of the ink chamber 79 in the tube 65 decreases and the air in the ink chamber 79 is compressed. . Therefore, when the on-off valve 69 is opened, ink is ejected vigorously from the base end opening 65a based on the pressure of the compressed gas. Therefore, the ink can be ejected vigorously from the base end opening 65a that has sucked the ink.

  (2) Since the clamping area B and the non-clamping area A are located on the circular motion locus of the pressing roller 77, the pressing roller 77 is positioned in the clamping area B and the non-clamping area A along with the circular motion. be able to. When the pressing roller 77 is positioned in the non-clamping area A, the block of the tube 65 is released and the internal space is released to the atmosphere. Therefore, the pressure in the internal space of the tube 65 can be easily adjusted by the amount of movement of the pressing roller 77 from the non-clamping region A.

  (3) The on-off valve 69 is opened and closed according to the control of the control unit 82, and the pressing motor 81 is driven to displace the pressing roller 77. Therefore, it is easy to suck and discharge ink from the base end opening 65a. Can be changed.

  (4) When ejecting ink from the base end opening 65a, the momentum of the ejected ink can be changed. That is, for example, the air release valve 73 is opened and the pressing roller 77 is displaced in a direction approaching the proximal end opening 65a. Then, since the volume of the ink chamber 79 decreases, air is discharged from the intermediate opening 65c. When the air release valve 73 is closed and the pressing roller 77 is further displaced in the direction approaching the proximal end opening 65a, the volume of the ink chamber 79 in the tube 65 decreases, and the air in the ink chamber 79 is reduced. Compressed. That is, the pressure in the ink chamber 79 at this time is smaller than that in the case where the air release valve 73 is closed when the pressing roller 77 starts to be displaced. Therefore, for example, even when the pressing roller 77 is circularly moved by a certain amount, the moment when ink is ejected from the base end opening 65a can be easily changed by changing the timing of opening and closing the air release valve 73. Can be changed.

  (5) When the ink is sucked into the ink chamber 79 of the tube 65 and the sensor 70 detects the ink, the control unit 82 closes the on-off valve 69 to restrict the movement of the ink. be able to. That is, since the ink moves closer to the base end opening 65a than the sensor 70, the possibility of ink leaking from the front end opening 65b and the intermediate opening 65c can be reduced.

  (6) By the displacement of one pressing roller 77, ink can be sucked and discharged for each of the plurality of base end openings 65a. That is, the internal space of each branch part 66 is in communication, and each branch part 66 is provided with an on-off valve 69. Therefore, for example, by opening one on-off valve 69 in a state where the air on the branch point Pb side is compressed from the position where the pressing roller 77 is closed, one base end opening corresponding to the opened on-off valve 69 is opened. Ink can be selectively ejected from the portion 65a. Further, by providing the sensor 70 at each branching portion 66, it is possible to suppress the infiltration of ink closer to the branching point Pb than the sensor 70. Therefore, even when different types of ink are sucked from the respective base end openings 65a, mixing of the inks can be suppressed.

  (7) Since the ink can be ejected vigorously from the maintenance pump 61, for example, a mechanism for applying a negative pressure from the recording head 26 side becomes unnecessary, and the printer 11 can be downsized.

(Second Embodiment)
Next, a second embodiment of the present invention will be described with reference to FIGS. The second embodiment is different in configuration from the first embodiment only in that the proximal end support portion 63a is not branched, and the other configurations are common, so the same components are the same. A detailed description thereof will be omitted by attaching a reference numeral.

  That is, as shown in FIG. 12, the tube 65 of the maintenance pump 84 as a tube pump is constituted by a base end support portion 63a and an elastic portion 62 formed in a cylindrical shape.

  Next, the operation when cleaning is performed by the maintenance pump 84 configured as described above will be described below. The printer 11 is initially filled in the same manner as in the first embodiment, the ink flow path 32 and the recording head 26 are filled with ink, and the maintenance pump 84 opens and closes by sucking ink to the sensor 70. It is assumed that the valve 69 is closed.

  As shown in FIG. 12, first, the control unit 82 closes the opening / closing valve 69 and drives the pressing motor 81 to rotate in the forward direction with the air release valve 73 opened. Then, since the pressing roller 77 moves circularly from the suction start position P1 in the direction indicated by the white arrow, the air is sucked from the intermediate opening 65c into the ink chamber 79 in which the volume increases, whereby the ink chamber 79 is filled. The inside is maintained at atmospheric pressure. On the other hand, in the gas chamber 80 whose volume decreases, the inside of the gas chamber 80 is maintained in an atmospheric pressure state by discharging air from the tip opening 65b.

  As shown in FIG. 13, the controller 82 opens the open / close valve 69 and closes the air release valve 73 while the pressing roller 77 moves from the suction start position P1 to the suction end position P2. . Note that the timing for switching between opening and closing of the opening / closing valve 69 and the atmosphere opening valve 73 is changed according to the pressure applied when ink is ejected, and is switched at a position closer to the suction start position P1 as ink is ejected more vigorously. It is done. Therefore, ink is sucked into the ink chamber 79 that increases with the movement of the pressing roller 77 from the ink flow path 32 through the proximal end opening 65a (suction drive).

  And as shown in FIG. 14, the control part 82 will close the on-off valve 69, if the press roller 77 is circularly moved to the suction completion position P2. Thereafter, the controller 82 drives the pressing motor 81 in the reverse direction to cause the pressing roller 77 positioned at the suction end position P2 to move in the direction indicated by the white arrow. Then, the accommodated air is compressed in the ink chamber 79 whose volume is reduced.

  That is, in the present embodiment, as shown in FIG. 14, after the ink is sucked from the base end opening 65a and the liquid level of the ink is moved to the front end side, the volume of the ink chamber 79 is shown in FIG. Decrease. Therefore, the volume in which the air is accommodated in the ink chamber 79 is compared with the case where the pressure roller 77 is moved from the suction end position P2 to the suction start position P1 while the ink liquid level is positioned in the vicinity of the sensor 70. Become smaller. Therefore, when the on-off valve 69 is opened with the pressing roller 77 positioned at the suction start position P1, the ink in the ink chamber 79 is ejected more vigorously from the base end opening 65a (ejection driving).

According to the said 2nd Embodiment, in addition to the effect of (1)-(7) in 1st Embodiment, the following effects can be acquired further.
(8) By sucking ink from the sensor 70 to the intermediate portion 62c side, the volume of air stored in the ink chamber 79 can be reduced. That is, for example, even when the volume of the intermediate portion 62c is reduced, the air can be sufficiently compressed and ink can be ejected vigorously.

In addition, you may change the said embodiment as follows.
In each of the above embodiments, the pressure applied to the ink may be adjusted also in the ejection drive during the initial filling process. Further, at the time of cleaning, the air release valve 73 may be closed before the pressing motor 81 is driven without adjusting the pressure applied to the ink.

  In each of the above embodiments, the intermediate opening 65c and the air release valve 73 may not be provided. Even in a configuration in which the intermediate opening 65c and the air release valve 73 are not provided, the pressure in the ink chamber 79 can be adjusted according to the amount of movement of the pressing roller 77 from the non-nipping region A.

  -In each said embodiment, it is good also as a structure which does not provide the non-clamping area | region A. FIG. In other words, the elastic portion 62 is provided in a state where it is rotated at least once, and the pressing roller 77 may close the intermediate portion 62c regardless of the position of the circular movement locus. In this case, the pressing roller 77 may be driven for suction or discharge by circularly moving the pressing roller 77 one or more times.

  In each of the above embodiments, the elastic portion 62 may be connected to the ink flow path 32, and the end portion on the proximal end side of the elastic portion 62 may be the one end side opening portion. Moreover, the edge part at the front end side of the elastic part 62 may be connected to another member, and the other end side opening part may be formed in this another member.

  In each of the above embodiments, if the proximal end opening portion 65a and the distal end opening portion 65b are formed on the distal end side or the proximal end side in the length direction of the tube 65 relative to the intermediate portion 62c of the elastic portion 62, It does not have to be a part.

  In each of the above embodiments, the maintenance pumps 61 and 84 can continuously perform the suction drive without performing the discharge drive. Therefore, the pressure pump 49 and the air flow path 48 may be omitted, and the ink may be sucked from the ink cartridge 31 by the maintenance pumps 61 and 84.

  In the first embodiment, the maintenance pump 61 may be provided corresponding to each ink flow path 32 without forming the branch portion 66. In the second embodiment, the branching portion 66 may be formed.

  In each of the above embodiments, the volume of the internal space from the on-off valve 69 to the sensor 70 in the tube 65 may be smaller than the volume of the intermediate portion 62 c in the elastic portion 62. In other words, the flow of ink can be restricted even when the opening / closing valve 69 closes the portion of the ink chamber 79 that contains air.

  In each of the above embodiments, when the maintenance pumps 61 and 84 are driven to suck, when the sensor 70 detects ink, the control unit 82 opens the air release valve 73 to limit ink suction. Also good.

  In each of the above embodiments, the sensor 70 is not provided, and for example, by restricting the movement range of the pressing roller 77, ink leakage from the tip opening 65b and the intermediate opening 65c may be suppressed. .

  In each of the above embodiments, the distal end opening 65b may be positioned below the base end opening 65a in the direction of gravity. That is, for example, the gas may be kept at the tip side depending on the thickness of the tube 65, the viscosity of the ink, and the surface tension.

  In each of the above embodiments, the maintenance pump 61 may be connected to the reservoir 36, and the ink in the reservoir 36 may be sucked and discharged. That is, when the maintenance pump 61 is connected to the reservoir 36, the reservoir 36 functions as a liquid supply channel that supplies ink to the nozzles 30.

  In each of the above embodiments, the pressing roller 77 is movable in the radial direction around the drive shaft 75, and is a closed section that can close the inner space of the tube 65, and is closer to the drive shaft 75 than the closed section. You may displace between non-occlusion sections.

  In each of the above embodiments, the control unit 82 may not be provided, and the user may manually perform drive control of the on-off valve 69, the air release valve 73, and the maintenance pumps 61 and 84.

  In each of the above embodiments, the liquid ejecting apparatus is embodied in the ink jet printer 11, but a liquid ejecting apparatus that ejects or discharges liquid other than ink may be employed. The present invention can be used for various liquid ejecting apparatuses including a liquid ejecting head that ejects a minute amount of liquid droplets. In addition, a droplet means the state of the liquid discharged from the said liquid ejecting apparatus, and shall also include what pulls a tail in granular shape, tear shape, and thread shape. The liquid here may be any material that can be ejected by the liquid ejecting apparatus. For example, it may be in a state in which the substance is in a liquid phase, such as a liquid with high or low viscosity, sol, gel water, other inorganic solvents, organic solvents, solutions, liquid resins, liquid metals (metal melts ) And a liquid as one state of a substance, as well as a material in which particles of a functional material made of a solid such as a pigment or metal particles are dissolved, dispersed or mixed in a solvent. Further, representative examples of the liquid include ink and liquid crystal as described in the above embodiment. Here, the ink includes general water-based inks and oil-based inks, and various liquid compositions such as gel inks and hot melt inks. As a specific example of the liquid ejecting apparatus, for example, a liquid containing a material such as an electrode material or a color material used for manufacturing a liquid crystal display, an EL (electroluminescence) display, a surface emitting display, a color filter, or the like in a dispersed or dissolved state. It may be a liquid ejecting apparatus for ejecting, a liquid ejecting apparatus for ejecting a bio-organic material used for biochip manufacturing, a liquid ejecting apparatus for ejecting a liquid as a sample used as a precision pipette, a textile printing apparatus, a microdispenser, or the like. In addition, transparent resin liquids such as UV curable resin to form liquid injection devices that pinpoint lubricant oil onto precision machines such as watches and cameras, and micro hemispherical lenses (optical lenses) used in optical communication elements. A liquid ejecting apparatus that ejects a liquid onto the substrate or a liquid ejecting apparatus that ejects an etching solution such as an acid or an alkali to etch the substrate may be employed. The present invention can be applied to any one of these liquid ejecting apparatuses.

  DESCRIPTION OF SYMBOLS 11 ... Printer (liquid ejecting apparatus), 12 ... Paper (target), 26-29 ... Recording head (liquid ejecting head), 31 ... Ink cartridge (liquid supply source), 32 ... Ink flow path (liquid supply flow path), 51 ... One-way valve, 61, 84 ... Maintenance pump (tube pump), 62 ... Elastic part (tube), 62c ... Intermediate part, 63a ... Base end support part (tube), 63c ... Intermediate support part (pump frame), 63d: support surface, 63e: notch, 65 ... tube, 65a ... proximal end opening (one end side opening), 65b ... distal end opening (other end side opening), 65c ... intermediate opening, 66 ... branch , 69 ... Open / close valve, 70 ... Sensor (detection means), 73 ... Air release valve, 77 ... Press roller (press member), 79 ... Ink chamber (internal space), 80 ... Gas chamber (internal space), 81 ... Pressure motor (driving means), 82 ... control unit (control means), A ... non-clamping area (non-occlusion section), B ... clamping area (occlusion section), Pb ... branching point, PH ... transformation position (second position) ), PT ... pressure adjusting position (first position).

Claims (7)

One end side opening that enables suction and discharge of liquid is provided on one end side in the length direction, and the other end side opening that opens to the atmosphere is provided on the other end side in the length direction and is long. A tube having elasticity in at least an intermediate portion in the vertical direction;
A pump frame having an arcuate cross-sectional support surface capable of supporting the intermediate portion of the tube along its length;
A pressing member that is capable of circular movement about an axis that is an arc center of the support surface so as to close the internal space of the tube between the support surface and the support surface;
An on-off valve capable of closing the one end side opening,
The pressing member circularly moves in a direction approaching the other end side opening in the length direction of the tube while crushing the intermediate portion of the tube in a state where the opening / closing valve is opened, and then the opening / closing valve The tube is closed and circularly moves in a direction approaching the one end side opening in the length direction of the tube while crushing the intermediate portion of the tube, and then the on-off valve is opened. pump. The pump frame has a cutout portion in which a part of the support surface is cut out in a circumferential direction around the axis.
When the pressing member presses the tube against the support surface, a closed section in which the inner space of the tube is closed and a non-closed section in which the pressing member is not in the notch portion are on the circular motion locus of the pressing member. The tube pump according to claim 1, wherein the tube pump is located. The tube pump according to claim 1 or 2, further comprising control means for controlling movement of the on-off valve and the pressing member. Between the intermediate portion in the length direction of the tube and the on-off valve, an intermediate opening that opens the internal space of the tube to the atmosphere,
The tube pump according to claim 3, further comprising: an air release valve capable of closing the intermediate opening by closing the intermediate opening based on the control of the control unit. Further comprising detection means for detecting the presence or absence of liquid in the inner space of the tube between the on-off valve and the intermediate portion in the length direction of the tube;
The said control means closes the said on-off valve, when a liquid is attracted | sucked in the internal space of the said tube from the said one end side opening part, and the said detection means detects the said liquid. The tube pump according to claim 4. The tube further includes a plurality of branch portions that branch at a branch point between the detection means and the intermediate portion in the length direction thereof and communicate with the internal space.
6. The tube pump according to claim 5, wherein the one end side opening, the on-off valve, and the detection means are provided for each of the branch portions. A liquid ejecting head that ejects liquid onto a target;
A liquid supply channel for supplying the liquid from an upstream side which is a liquid supply source side toward a downstream side which is the liquid jet head side;
A one-way valve which is provided at a first position in the liquid supply flow path and allows passage of the liquid from the upstream side to the downstream side;
The liquid can be sucked and discharged from the second position by connecting the opening on the one end side to a second position downstream of the first position in the liquid supply channel. A liquid ejecting apparatus comprising: the tube pump according to any one of claims 1 to 6.

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