JP2011245748A - Tube pump, and liquid ejection apparatus - Google Patents

Abstract

To provide a tube pump and a liquid ejecting apparatus capable of selectively executing a plurality of patterns of fluid suction and discharge through openings formed in the tube length direction with a simple configuration.
A base end opening 65a capable of sucking and discharging ink, a distal end opening 65b and an intermediate opening 65c that open an internal space to the atmosphere, and an elastic portion 62 having elasticity are provided in a longitudinal direction. The drive shaft is centered between the tube 65 having different positions, the frame 63 having the support surface 63d capable of supporting the elastic portion 62 along its length direction, and the clamping region B and the non-clamping region A. As a circularly movable pressing roller 77 and first and second atmospheric release valves 71 and 73, and the pressing roller 77 has a direction approaching the proximal end opening in the length direction of the tube 65 and a proximal end opening. The pressing roller can move circularly in one direction and move in the clamping area B and then move to the non-clamping area A.
[Selection] Figure 3

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.

JP 2004-137940 A

  By the way, in the case of the tube pump of Patent Document 1, ink is sucked from one end of the tube and ejected from the other end of the tube as the abutting member moves circularly in one direction. However, in such a tube pump, there are cases where it is desired to perform both suction and discharge of ink from one end side of the tube. However, in the case of the tube pump of Patent Document 1, in order to eject ink from one end side where ink has been sucked, the contact member must be circularly moved in the direction opposite to that at the time of sucking, and the configuration becomes complicated. There was a problem that.

  The present invention has been made in view of the above problems, and its purpose is to select and execute a plurality of patterns of fluid suction and discharge through a plurality of openings formed in the length direction of the tube with a simple configuration. An object of the present invention is to provide a tube pump and a liquid ejecting apparatus that can perform the above operation.

  In order to achieve the above object, a tube pump according to the present invention includes at least one first opening capable of sucking and discharging fluid, and at least one second opening opening an internal space to the atmosphere. A tube having elastic portions at different positions in the length direction, and a pump frame having a support surface having an arcuate cross section capable of supporting the elastic portion of the tube along the length direction; Centering on an axis that is the center of the arc of the support surface between a closed section that crushes the elastic portion and closes the inner space of the tube between the support surface and a non-closed section that is different from the closed section As a circularly movable pressing member, and an air release valve capable of closing the second opening, and the pressing member approaches the first opening in the length direction of the tube and the first opening 1 It is possible to make a circular motion in either one of the directions away from the opening, and the pressing member moves circularly in the one direction and moves in the closed section, and then further circularly moves in the one direction. Move to the non-blocking section.

  According to this configuration, by changing the valve opening state of the atmosphere release valve, the fluid suction and discharge patterns in the first opening and the second opening can be changed. That is, for example, the first opening portion, the elastic portion, and the second opening portion are formed in order from one end side in the length direction, and the first member is kept in a state where the pressing member is positioned in the closed section and the tube is crushed. Make a circular motion in one direction away from the opening. Then, in the internal space closer to the first opening than the crushed position in the tube, the volume increases and becomes negative pressure, so that fluid is sucked from the first opening. On the other hand, the volume of the internal space on the second opening side relative to the crushed position in the tube decreases. Therefore, when the air release valve is closed, the gas in the internal space is compressed, whereas when the air release valve is opened, the gas is discharged from the second opening. Thus, the interior space is maintained at atmospheric pressure. Therefore, when the pressing member is further moved in a direction closer to the second opening and displaced into the non-blocking section, the internal space on the second opening side is closed when the air release valve is closed. The fluid is pushed back to the first opening side by the pressure of the gas compressed inside and discharged. On the other hand, since the fluid is not discharged when the air release valve is open, the fluid is repeatedly sucked from the first opening by the circular movement of the pressing member repeatedly, and the second opening The gas is discharged from. Therefore, suction and discharge of a plurality of patterns of fluid through a plurality of openings formed in the length direction of the tube can be selected and executed with a simple configuration.

  In the tube pump of the present invention, the pump frame has a cutout portion in which a part of the support surface is cut out in a circumferential direction centering on the axis, and the non-blocking section includes the pressing member It is a section with respect to the notch, and the closed section is a section in which the pressing member presses the tube against the support surface to block the internal space of the tube.

  According to this configuration, by causing the pressing member to make a circular motion about the axis, the pressing member moves alternately between the non-blocking section with respect to the notch and the blocking section with respect to the support surface. Therefore, the suction and discharge of the liquid from the opening can be performed alternately by causing the pressing member to continuously perform the circular motion in one direction. That is, for example, even when a small tube pump is used, it is possible to easily supply a liquid having a single discharge amount or more.

The tube pump of the present invention further includes control means for controlling movement of the atmosphere release valve and the pressing member.
According to this configuration, the air release valve is opened and closed according to the control of the control means, and the pressing member moves, so that the patterns of suction and discharge of the fluid from the first opening and the second opening are changed. Can be easily changed.

  In the tube pump of the present invention, the second opening is formed at each position on both sides of the elastic portion in the length direction of the tube, and the atmosphere release valve is provided for each second opening. A plurality are provided to be able to close.

  According to this configuration, when the fluid is ejected from the first opening, the amount of fluid to be ejected and the pressure applied to the fluid can be changed. That is, for example, each air release valve is opened, and the pressing member is positioned in the closed section, and the tube is crushed in a direction away from the first opening while the tube is crushed. Then, in the internal space closer to the first opening than the position pressed by the pressing member, the volume increases and becomes negative pressure, so the second opening formed on the same side as the first opening Gas is sucked from the part. On the other hand, since the volume of the internal space on the side opposite to the first opening is reduced, gas is discharged from the second opening. Then, when each atmosphere release valve is closed and the pressing member is positioned in the closed section and the tube is crushed in a direction moving away from the first opening, the crushed position in the tube Also, the internal space on the first opening side is depressurized and fluid is sucked from the first opening. Moreover, in the internal space opposite to the first opening from the crushed position in the tube, the volume is reduced and the gas in the internal space is compressed. That is, the amount of fluid sucked at this time is smaller than that when the air release valve is closed when the pressing member is displaced from the non-closed section to the closed section, and the internal volume accompanying the compression of the gas. The pressure in the space is also getting smaller. Therefore, by changing the timing for opening and closing the atmosphere release valve, the amount of fluid sucked from the first opening and the momentum at the time of discharge can be changed.

  The tube pump according to the present invention further includes an on-off valve capable of closing the first opening, and the control means determines the opening time of the on-off valve in accordance with the amount of fluid discharged from the first opening. To change.

  According to this configuration, the fluid can be ejected vigorously regardless of the circular movement direction of the pressing member, and the amount of the ejected fluid can be changed. That is, for example, even when the pressing member is moved toward the first opening portion in a state where the pressing member is positioned in the closed section, the fluid can be obtained by moving the pressing member with the on-off valve closed. In the internal space where the movement of is restricted, the gas is compressed and the pressure is increased. Therefore, when the on-off valve is opened, the fluid is vigorously discharged from the first opening due to the pressure of the compressed gas, and at the same time, the on-off valve that is opened is closed. The amount of fluid discharged can be adjusted.

  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 first opening and the second opening, and the control means includes the first When the liquid is sucked into the internal space of the tube from one opening 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 first opening than the detection means, it is possible to reduce the possibility that the liquid leaks from the second opening.

  In the tube pump of the present invention, the volume of the internal space between the detection means and the opening / closing valve is larger than the volume of the internal space of the elastic portion that can be pressed by the pressing member.

  According to this configuration, since the liquid sucked from the first opening can be moved so that the liquid level is located between the on-off valve and the detection means, the on-off valve The movement of the liquid can be restricted by dividing. Therefore, it can suppress that gas enters into the 1st opening side rather than the on-off valve in a tube.

  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 elastic portion in the length direction thereof and communicate with the internal space, and the branch portions. Each has the first opening, the on-off valve, and the detection means.

  According to this configuration, the fluid can be sucked and discharged for each of the plurality of first openings by the circular motion 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 branching point side is compressed from the position where the pressing member is closed, it is selected from one first opening corresponding to the opened on-off valve Thus, the fluid 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 1st 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 first opening to a second position on the side;

  If the liquid ejecting apparatus is transported in a state where the liquid supply channel is filled with the liquid, the liquid may leak from the liquid ejecting head or the like. Therefore, in general, after the liquid ejecting apparatus is installed, a liquid is filled in the liquid supply channel and the liquid ejecting head by applying a negative pressure to the liquid supply channel from the liquid ejecting head side. For this reason, when the liquid is filled, a large amount of liquid has been discharged from the liquid ejecting head. In this respect, according to this configuration, the tube pump can suck the fluid from the first opening and discharge the gas from the second opening. The liquid can be aspirated. Furthermore, since the tube pump can also discharge liquid from the first opening, the liquid sucked up to the tube pump is pressurized and supplied to the liquid ejecting head side to suppress liquid consumption, The liquid can be filled in the liquid ejecting head.

1 is a schematic diagram of a printer according to a first embodiment. FIG. 2 is a schematic diagram of an ink supply system. The schematic diagram of the maintenance pump at the time of a suction drive start. 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. The schematic diagram of the maintenance pump at the time of discharge drive. 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. The schematic diagram of the maintenance pump of 3rd Embodiment. Schematic diagram of maintenance pump during cleaning. 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 4th Embodiment. Schematic diagram of the maintenance pump during initial filling. Schematic diagram of the maintenance pump during initial filling. Schematic diagram of the maintenance pump during initial filling. The schematic diagram of the maintenance pump of 5th 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 configuration of each branching portion 66 is the same, only the first branching portion 66a and the second branching portion 66b are shown in FIG. 3, and the first branching portion 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 (one end side in the length direction of the tube 65) of each branching portion 66 is a base end opening as a first opening capable of sucking and discharging ink. A portion 65 a 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) serves as a distal end opening portion 65b as a second opening portion that opens the internal space of the tube 65 to the atmosphere. ing. A first atmosphere release valve 71 capable of closing the tip opening 65b is provided at the tip support portion 63b of the frame 63.

  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 formed with an intermediate opening 65c as a second opening that opens the internal space of the tube 65 to the atmosphere, and the second atmosphere that can close the intermediate opening 65c. An open valve 73 is provided.

  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 rotates on a rotating plate 76 that can rotate around a drive shaft 75 as an axis that is the center of the arc of the support surface 63d, and on the tip of a tongue piece 76a that protrudes radially outward of the rotating plate 76. A pressing roller 77 serving as a pressing member is provided. 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.

  When the drive shaft 75 rotates as the pressing motor 81 (see FIG. 2) is driven, the pressing roller 77 moves circularly in the direction indicated by the white arrow in FIG. It is like that. 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 moves circularly from the suction end position P2 shown in FIG. 5 and is positioned in the non-clamping area A (see FIG. 3) as a non-blocking section with respect to the notch 63e as shown in FIG. The clamping state of the part 62 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. In the maintenance pump 61, the pressure motor 81 rotates the drive shaft 75 to displace the pressure roller 77 through the non-nipping region A and the sandwiching region B in sequence, thereby causing the ink chamber 79 and the gas chamber 80 to move. The volume is changed to drive the ejection and suction.

  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. The control of the maintenance pump 61 is, as shown in FIG. 4, the on / off valves 69 and the first and second atmospheric release valves 71 and 73 based on the detection results of the sensors 70 provided on the branch portions 66. Open / close control.

  Next, the operation of the printer 11 configured as described above will be described below. In the drawing, among the on-off valve 69 and the first and second atmospheric release valves 71 and 73, the valve in the open state 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 the first atmosphere release valve 71 and drives the pressing motor 81 with the second atmosphere release valve 73 closed. Then, since the pressing roller 77 moves circularly in a direction away from the proximal end opening 65a in the length direction of the tube 65 from the suction start position P1, the inside of the ink chamber 79 in which the volume increases increases via the proximal end opening 65a. Thus, 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 is displaced to the non-nipping region A (see FIG. 6), the ink chamber 79 and the gas chamber 80 communicate with each other. 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 second 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 is displaced to the non-clamping region A, ink is not ejected from the base end opening 65a, and the ink level is located in the vicinity of the sensor 70. .

  Now, as shown in FIG. 7, when ink is sucked up to the sensor 70, the control unit 82 causes the maintenance pump 61 to alternately perform ejection driving and suction driving. That is, the control unit 82 closes all the on-off valves 69 and the first atmospheric release valve 71 and drives the pressing motor 81 with the second atmospheric release valve 73 opened, thereby causing the pressing roller 77 to move. Circularly move in the direction indicated by the white arrow (counterclockwise direction).

  Then, air is sucked into the ink chamber 79 whose volume is increased from the intermediate opening 65c, whereas the stored air is compressed in the gas chamber 80 whose volume is decreased. Then, as shown in FIG. 8, when the pressing roller 77 is displaced to the suction end position P2, the control unit 82 closes the second atmospheric release valve 73 and opens each on-off valve 69. Then, the pressing motor 81 is further driven to displace the pressing roller 77 to the non-clamping area A.

  That is, as shown in FIG. 9, when the pressing roller 77 moves to the non-clamping region A, the pressure of the air compressed in the gas chamber 80 acts in the ink chamber 79 in the atmospheric pressure state. Therefore, ink (liquid and fluid) in the ink chamber 79 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.

  That is, as shown in FIG. 9, the control unit 82 opens the on-off valve 69, closes the first and second atmosphere release valves 71, 73, and further drives the pressing motor 81 to press the pressing roller. 77 is moved in the direction indicated by the white arrow. Then, since the volume of the ink chamber 79 is increased, ink is sucked from the ink flow path 32 through the base end opening 65a (suction drive).

  When the maintenance pump 61 is driven for suction, the negative pressure associated with the suction drive also acts on the ink flow path 32, so that the film 57 is displaced in the direction in which the volume of the pressure chamber 53 decreases and the one-way valve 51 is opened. Ink is supplied from the ink cartridge 31 side.

  When the ink is sucked up to the sensor 70, the controller 82 closes the open / close valve 69 and opens the second atmosphere release valve 73 (see FIG. 7). Therefore, even if the pressing roller 77 further moves circularly, the ink level is positioned in the vicinity of the sensor 70, and air is sucked from the intermediate opening 65c, so that the ink chamber 79 is brought into an atmospheric pressure state. On the other hand, since the volume of the gas chamber 80 decreases, the air in the gas chamber 80 is compressed.

  Thereafter, when the pressing roller 77 moves to the suction end position P2, the control unit 82 corresponds to the branching unit 66 corresponding to the recording head that performs cleaning (for example, the first branching unit 66a corresponding to the first recording head 26). The on-off valve 69 is opened, and the second atmosphere release valve 73 is closed. Then, the pressing motor 81 is further driven to position the pressing roller 77 in the non-clamping area A. Then, the ink chamber 79 and the gas chamber 80 communicate with each other, and the pressure of the air compressed in the gas chamber 80 acts on the ink chamber 79, and ink is ejected from the base end opening 65 a to the ink flow path 32 with a strong force. Is done.

  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 closes the opening / closing valve 69 when the valve opening time corresponding to the amount of ink to be ejected has elapsed after the pressing roller 77 has moved to the non-nip region A. 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.

According to the first embodiment, the following effects can be obtained.
(1) By changing the open state of the first and second atmosphere release valves 71 and 73, the ink and air suction and discharge patterns at the proximal end opening 65a and the distal end opening 65b can be changed. it can. That is, the pressing roller 77 is positioned in the clamping region B and is circularly moved in one direction away from the proximal end opening 65a while the tube is crushed. Then, since the volume of the ink chamber 79 on the proximal end opening 65a side of the pressing point 62d in the tube 65 is increased to a negative pressure, ink or air is sucked from the proximal end opening 65a. On the other hand, the volume of the gas chamber 80 on the distal end opening 65b side of the pressing point 62d in the tube 65 decreases. Therefore, when the first atmosphere release valve 71 is closed, the air in the gas chamber 80 is compressed, whereas when the first atmosphere release valve 71 is opened, Air is discharged from the tip opening 65b, and the gas chamber 80 is maintained in an atmospheric pressure state. Accordingly, when the pressing roller 77 further moves in the one direction approaching the tip opening 65b and is displaced to the non-clamping region A, the tip opening 65b is closed when the first atmosphere release valve 71 is closed. Ink is pushed back toward the base end opening 65a by the pressure of the air compressed in the gas chamber 80 on the side, and is ejected. On the other hand, since the ink is not ejected when the first atmosphere release valve 71 is open, the air is repeatedly sucked from the base end opening 65a by the circular movement of the pressing roller 77, Air is discharged from the tip opening 65b. Therefore, it is possible to select and execute suction and discharge of a plurality of patterns of ink and air through the proximal end opening 65a and the distal end opening 65b formed in the length direction of the tube 65 with a simple configuration.

  (2) By causing the pressing roller 77 to move circularly about the drive shaft 75, the pressing roller 77 alternately moves between the non-clamping area A for the notch 63e and the clamping area B for the support surface 63d. Therefore, by causing the pressing roller 77 to continuously perform a circular motion in one direction, ink suction and discharge from the proximal end opening 65a can be performed alternately. That is, for example, even when a small tube pump is used, it is possible to easily supply a liquid having a single discharge amount or more.

  (3) Since the first and second atmosphere release valves 71 and 73 are opened and closed according to the control of the control unit 82 and the pressing roller 77 moves, the ink from the base end opening 65a and the tip opening 65b In addition, the air suction and discharge patterns can be easily changed.

  (4) 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 opening / closing 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 risk of ink leaking from the front end opening 65b can be reduced.

  (5) Since the ink sucked from the base end opening 65 a can be moved so that the liquid level is located between the on-off valve 69 and the sensor 70, the on-off valve 69 is used for the ink in the ink chamber 79. The movement of the ink can be restricted by dividing. Therefore, it is possible to prevent air (gas) from entering the proximal end opening 65a side of the open / close valve 69 in the tube 65.

  (6) By the circular motion 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 pressure roller 77 compresses the gas on the branch point Pb side from the pressing point 62d, one base end opening corresponding to the opened on-off valve 69 is opened. Ink can be selectively ejected from the portion 65a. In addition, by providing a sensor in each branch portion 66, it is possible to suppress the intrusion of ink closer to the branch 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) If the printer 11 is transported while the ink flow path 32 is filled with ink, the ink may leak from the recording heads 26 to 29 and the like. Therefore, in general, after the printer 11 is installed, a negative pressure is applied to the ink flow path 32 from the recording heads 26 to 29 side, thereby filling the ink flow path 32 and the recording heads 26 to 29 with ink. Yes. Therefore, when ink is filled, a large amount of ink has been discharged from the recording heads 26 to 29. In this respect, the maintenance pump 61 can suck ink and air from the base end opening 65a and discharge air from the tip opening 65b, so that the ink is passed from the ink cartridge 31 side through the one-way valve 51. Can be aspirated. Further, since the maintenance pump 61 can also eject ink from the base end opening 65a, the ink sucked up to the maintenance pump 61 is supplied under pressure to the recording heads 26 to 29, thereby suppressing ink consumption and ink. The ink can be filled into the flow path 32 and the recording heads 26 to 29.

  (8) By moving the pressing roller 77 toward the tip opening 65b with the first and second atmosphere release valves 71 and 73 closed, ink suction and gas compression can be performed simultaneously. Accordingly, the recording heads 26 to 29 can be quickly cleaned.

(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. 10, the tube 65 of the maintenance pump 84 serving as a tube pump includes a proximal end support portion 63 a and an elastic portion 62 that are 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. 10, first, the control unit 82 maintains the open / close valve 69 in a closed state, opens the first and second atmospheric release valves 71 and 73, and drives the pressing motor 81. 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. 11, the controller 82 opens the on-off valve 69 and opens the first and second atmospheres while the pressing roller 77 moves from the suction start position P1 to the suction end position P2. The valves 71 and 73 are closed. Note that the timing for switching between opening and closing of the on-off valve 69 and the first and second atmosphere release valves 71 and 73 is changed according to the amount of ink to be ejected. The smaller the ink amount to be ejected, the more the pressing roller 77 is at the suction end position P2. Is switched at a timing closer to.

  Therefore, as shown in FIG. 12, ink is sucked from the ink flow path 32 into the ink chamber 79 that increases as the pressing roller 77 moves (suction drive) through the base end opening 65a. In the gas chamber 80 whose volume decreases, the stored air is compressed.

  As shown in FIG. 13, when the pressing roller 77 is moved to the non-clamping region A, the pressure of the air compressed in the gas chamber 80 acts on the ink via the air in the ink chamber 79. Therefore, the ink in the ink chamber 79 is discharged to the ink flow path 32, and the maintenance pump 61 is driven to discharge.

According to the said 2nd Embodiment, in addition to the effect of (1)-(9) in 1st Embodiment, the following effects can be acquired further.
(10) When ink is ejected from the base end opening 65a, the amount of ink to be ejected and the pressure applied to the ink can be changed. That is, the first and second air release valves 71 and 73 are opened, and the pressing roller 77 is positioned in the clamping region B and the intermediate portion 62c is crushed in a direction away from the proximal opening 65a. Make a circular motion. Then, in the ink chamber 70 closer to the base end opening 65a than the pressing point 62d, the volume increases to a negative pressure. Is sucked. On the other hand, since the volume of the gas chamber 80 on the side opposite to the base end opening 65a is reduced, air is discharged from the tip opening 65b. Then, the first and second air release valves 71 and 73 are closed, and the pressing roller 77 is positioned in the clamping region B and the intermediate portion 62c is crushed in a direction away from the proximal end opening 65a. When the circular movement occurs, the ink chamber 79 closer to the base end opening 65a than the pressing point 62d is decompressed, and ink is sucked from the base end opening 65a. Further, in the gas chamber 80 opposite to the base end opening 65a from the pressing point 62d, the volume thereof is reduced and the gas in the gas chamber 80 is compressed. That is, the amount of ink sucked at this time is compared with the case where the first and second atmosphere release valves 71 and 73 are closed when the pressing roller 77 is displaced from the non-clamping area A to the clamping area B. While decreasing, the pressure in the gas chamber 80 accompanying air compression is also reduced. Therefore, by changing the timing of opening and closing the first and second atmosphere release valves 71 and 73, the amount of ink sucked from the proximal end opening 65a and the momentum at the time of ejection can be changed. .

  (11) By simultaneously opening and closing the on-off valve 69 and opening and closing the first and second atmosphere release valves 71 and 73, the amount of ink sucked by the suction drive can be discharged by the discharge drive. Further, the amount of ink ejected can be easily controlled by the opening / closing timing of the opening / closing valve 69 and the first and second atmosphere opening valves 71, 73.

(Third embodiment)
Next, a third embodiment of the present invention will be described with reference to FIGS. The third embodiment is different from the second embodiment only in that the opening / closing control of the opening / closing valve 69 and the first and second atmosphere opening valves 71, 73 is changed. Are common. For this reason, the same components are denoted by the same reference numerals, and detailed description thereof is omitted.

  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. 14, first, the control unit 82 maintains the open / close valve 69 in the closed state, opens the first and second atmospheric release valves 71 and 73, and drives the pressing motor 81. . 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, the volume in the gas chamber 80 is reduced, and the air in the gas chamber 80 is discharged from the tip opening 65b, whereby the gas chamber 80 is maintained in an atmospheric pressure state.

  Further, as shown in FIG. 15, the control unit 82 closes the first atmosphere release valve 71 during the movement from the suction start position P1 to the suction end position P2. Note that the timing for switching the opening and closing of the first atmosphere release valve 71 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. . And if the press roller 77 moves further, the accommodated air is compressed in the gas chamber 80 whose volume decreases.

  Then, as shown in FIG. 16, when the pressing roller 77 moves to the suction end position P2, the controller 82 opens the on-off valve 69 and closes the second atmosphere release valve 73. Further, as shown in FIG. 17, when the pressing roller 77 is moved to the non-clamping region A, the pressure of the air compressed in the gas chamber 80 acts on the ink via the air in the ink chamber 79 and the ink chamber 79. The ink inside is ejected to the ink flow path 32 (ejection drive).

  Thereafter, the controller 82 opens the first air release valve 71 in a state where the pressing roller 77 is positioned in the non-clamping region A. Then, since the ink chamber 79 and the gas chamber 80 communicate with each other, air is discharged from the tip opening 65b, and the internal space of the tube 65 is set to atmospheric pressure. In this state, as shown in FIG. 18, the control unit 82 causes the pressing roller 77 to perform a circular motion (suction drive), thereby sucking and stopping ink from the base end opening 65a.

According to the said 3rd Embodiment, in addition to the effect of (1)-(11) in 1st Embodiment and 2nd Embodiment, the following effects can be acquired further.
(12) By changing the timing at which the first atmosphere release valve 71 is closed, the pressure applied to the ink when the maintenance pump 84 is driven to discharge can be changed.

(Fourth embodiment)
Next, a fourth embodiment of the present invention will be described with reference to FIGS. The fourth embodiment is different from the second embodiment in that the configuration of the elastic portion is different and the circular motion direction of the pressing roller 77 is changed. And since the other structure is common, the same code | symbol is attached | subjected about the same structure part, and the detailed duplication description is abbreviate | omitted.

  That is, as shown in FIG. 19, the tube 86 of the maintenance pump 85 as a tube pump is comprised by the base end support part 63a and the elastic part 87 which were formed in the cylinder shape. The elastic portion 87 is supported by the proximal end support portion 63a on the proximal end side, whereas the distal end side is closed to form a distal end closed portion 86b. Further, an intermediate opening 86c serving as a second opening that opens the internal space of the tube 86 to the atmosphere is formed on the base end side of the elastic portion 87 with respect to the intermediate portion 87c.

  Further, the pressing roller 77 is positioned in the clamping region B (see FIG. 3) with the driving of the pressing motor 81, and the proximal end as the first opening of the tube 86 while pressing the elastic portion 87. Circular movement in one direction approaching the opening 86a (clockwise direction indicated by a white arrow).

Next, the operation when the printer 11 is initially filled using the maintenance pump 85 configured as described above will be described below.
Now, as shown in FIG. 19, the controller 82 closes the opening / closing valve 69 and opens the second atmosphere opening valve 73 to drive the pressing motor 81. Then, since the pressing roller 77 moves circularly from the discharge start position P3 in the direction indicated by the white arrow, in the ink chamber 79 where the volume decreases, the inside of the ink chamber 79 is discharged by discharging air from the intermediate opening 86c. Atmospheric pressure is maintained. On the other hand, the volume of the gas chamber 80 increases, and the inside of the gas chamber 80 is depressurized.

Then, as shown in FIG. 20, when the pressing roller 77 moves to the discharge end position P4, the controller 82 opens the on-off valve 69 and closes the second atmosphere release valve 73.
Furthermore, as shown in FIG. 21, when the pressure roller 77 moves to the non-clamping region A, the negative pressure in the gas chamber 80 is transmitted to the ink chamber 79, so that the ink (or air) in the ink flow path 32 is transferred. Is sucked from the proximal end opening 86a (suction drive). Therefore, by driving the maintenance pump 85 as described above, the maintenance pump 85 repeatedly performs suction driving.

  When the ink is sucked up to the sensor 70, the control unit 82 causes the maintenance pump 85 to repeatedly execute the ejection driving and the suction driving to fill the ink flow path 32 and the recording head 26 with ink. Similarly, when the recording head 26 is cleaned, the ejection drive and the suction drive are repeated.

  That is, from the state shown in FIG. 21, the control unit 82 closes the opening / closing valve 69 and drives the pressing motor 81 to cause the pressing roller 77 to move circularly. Then, as shown in FIG. 22, in the ink chamber 79 whose volume is reduced, the air in the ink chamber 79 is compressed. Moreover, the gas chamber 80 whose volume increases is decompressed. Therefore, when the opening / closing valve 69 is opened with the pressing roller 77 positioned at the discharge end position P4, the ink in the ink chamber 79 is discharged from the base end opening 86a to the ink flow path 32 (discharge drive). . Then, the control unit 82 closes the opening / closing valve 69 according to the amount of ink to be ejected.

Further, after the maintenance pump 85 is driven to discharge, the control unit 82 sucks ink to the sensor 70 by driving the maintenance pump 85 to suck.
According to the said 4th Embodiment, in addition to the effect of (1)-(12) in 1st Embodiment-3rd Embodiment, the following effects can be acquired further.

  (13) The liquid can be ejected vigorously regardless of the circular movement direction of the pressing roller 77, and the amount of ink ejected can be changed. That is, even when the pressing roller 77 is moved toward the proximal end opening 86a while being in the clamping region B, the pressing roller 77 is moved with the on-off valve 69 closed. Thus, in the ink chamber 79 where the movement of the ink is restricted, the air is compressed and the pressure is increased. Therefore, when the on-off valve 69 is opened, ink is ejected vigorously from the base end opening 86a by the pressure of the compressed air, and the open on-off valve 69 is closed to thereby close the base end opening. The amount of ink ejected from 86a can be adjusted.

(Fifth embodiment)
Next, a fifth embodiment of the present invention will be described with reference to FIGS. The fifth embodiment is different from the second embodiment in that the on-off valve 69 is not provided, and in that the circular motion direction of the pressing roller 77 is changed. And since the other structure is common, the same code | symbol is attached | subjected about the same structure part, and the detailed duplication description is abbreviate | omitted.

  That is, in the maintenance pump 88 as a tube pump, the pressing roller 77 moves circularly in the clockwise direction indicated by the white arrow as the pressing motor 81 is driven as in the fourth embodiment. Further, it is assumed that the printer 11 is subjected to the initial filling process as in the fourth embodiment, and the ink is sucked up to the sensor 70.

  As shown in FIG. 23, when performing cleaning, the control unit 82 opens the first and second atmosphere release valves 71 and 73 and drives the pressing motor 81. Then, the pressing roller 77 located at the discharge start position P3 performs a circular motion in the direction indicated by the white arrow.

  Then, in the ink chamber 79 whose volume is reduced, air is discharged from the intermediate opening 65c, and the inside of the ink chamber 79 is maintained in an atmospheric pressure state. Therefore, the ejection of ink from the base end opening 65a is suppressed, and the ink remains in the vicinity of the sensor 70. Further, the gas chamber 80 whose volume is increased is kept in an atmospheric pressure state because air is sucked from the tip opening 65b.

  Then, as shown in FIG. 24, the controller 82 closes the first and second atmosphere release valves 71 and 73 while the pressing roller 77 moves from the discharge start position P3 to the discharge end position P4. The timing at which the first and second atmosphere release valves 71 and 73 are closed is changed according to the amount of ink to be ejected, and the timing at which the pressing roller 77 approaches the ejection end position P4 as the amount of ink to be ejected decreases. Can be switched.

  When the pressing roller 77 further moves circularly, as shown in FIG. 25, ink is ejected from the base end opening 65a in the ink chamber 79 where the volume decreases. On the other hand, the gas chamber 80 whose volume increases has a negative pressure.

  Therefore, as shown in FIG. 26, when the pressing roller 77 is moved to the non-clamping region A, the negative pressure in the gas chamber 80 acts on the ink chamber 79 and the ink is sucked from the ink flow path 32. Since the first and second atmosphere release valves 71 and 73 are closed at the same time, the amount of ink ejected from the base end opening 65a is sucked from the ink flow path 32, and the ink level is near the sensor 70. Located in.

According to the said 5th Embodiment, in addition to the effect of (1)-(13) in 1st Embodiment-4th Embodiment, the following effects can be acquired further.
(14) The ink discharge amount is adjusted by closing the first and second atmosphere release valves 71 and 73 while the pressing roller 77 moves between the discharge start position P3 and the discharge end position P4. be able to. That is, since the press roller 77 closes the first and second atmosphere release valves 71 and 73 at a position close to the discharge start position P3, more ink is discharged. The discharge amount can be easily adjusted as compared with the case of restricting the flow.

In addition, you may change the said embodiment as follows.
In each of the above embodiments, the first and second atmosphere release valves 71 and 73 may be opened and closed at different timings.

  In each of the above embodiments, the elastic portions 62 and 87 may be connected to the ink flow path 32, and the end portion on the proximal end side of the elastic portions 62 and 87 may be the first opening. Moreover, the edge part of the front end side of the elastic parts 62 and 87 may be connected to another member, and a 2nd opening part may be formed in this separate member.

  In each of the above embodiments, the proximal end openings 65a and 86a and the distal end opening 65b are closer to the distal end side or the proximal end side in the length direction of the tubes 65 and 86 than the intermediate portions 62c and 87c of the elastic portions 62 and 87. As long as each is formed, it may not be an end.

  In each of the above embodiments, the maintenance pumps 61, 84, 85, and 88 can continuously perform suction driving without performing discharge driving. Therefore, the pressurizing 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, 84, 85, 88.

  In the first embodiment, the maintenance pump 61 may be provided corresponding to each ink flow path 32 without forming the branch portion 66. Further, in the second to fifth embodiments, the branch portion 66 may be formed. However, when the branching portion 66 is formed in the second embodiment, it is preferable that the maintenance pump 61 is driven to be sucked from a state in which the ink level is positioned in the vicinity of the base end opening 65a.

  In each of the above embodiments, the volume of the internal space from the on-off valve 69 to the sensor 70 in the tubes 65 and 86 may be smaller than the volume of the intermediate portions 62c and 87c in the elastic portions 62 and 87. 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, 84, 85, 88 are driven for suction, when the sensor 70 detects ink, the control unit 82 opens the second atmospheric release valve 73 to open the ink The suction may be limited.

  In each of the above embodiments, the sensor 70 may not be provided. That is, for example, as in the fifth embodiment, by opening and closing the first and second atmosphere release valves 71 and 73 at the same timing, it is possible to suck the ejected amount of ink.

-In the said 1st-4th embodiment, it is good also as a structure which does not provide the on-off valve 69 like 5th Embodiment. In the fifth embodiment, an on-off valve 69 may be provided.
In the first to third embodiments, the intermediate opening 65c and the second atmosphere release valve 73 may not be provided. In this case, the pressure roller 77 is circularly moved toward the distal end side in the length direction of the tube 65 with the first air release valve 71 opened, thereby sucking ink from the proximal end opening 65a. be able to. Further, when the pressing roller 77 is circularly moved with the first air release valve 71 closed, the maintenance pump 61 alternately performs suction drive and discharge drive.

  In each of the above embodiments, the pressure roller 77 is positioned at the suction end position P2 and the discharge end position P4 during non-cleaning, and the pressure roller 77 is circled around the drive shaft 75 from the suction end position P2 and the discharge end position P4 during cleaning. You may exercise. That is, for example, the maintenance pumps 61, 84, 85, 88 may be in a state where the volume of the ink chamber 79 is increased and the volume of the gas chamber 80 is reduced and the gas is compressed. . Further, the pressing roller 77 may be stopped in the non-clamping area A.

  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 a closed section in which the inner space of the tubes 65 and 86 can be closed, and the drive shaft 75 side of the closed section. It may be displaced between the non-blocking sections.

  In each of the above embodiments, the control unit 82 is not provided, and the user performs drive control of the on-off valve 69, the first and second atmosphere release valves 71 and 73, and the maintenance pumps 61, 84, 85, and 88. It may be performed manually.

  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, 85, 88 ... Maintenance pump (tube pump), 62, 87 ... Elastic part (tube), 63a ... Base end support part (tube), 63c ... Intermediate support part (pump frame. ), 63d ... support surface, 63e ... notch, 65, 86 ... tube, 65a, 86a ... proximal end opening (first opening), 65b ... distal end opening (second opening), 65c, 86c ... Intermediate opening (second opening), 66 ... Branch, 69 ... Open / close valve, 70 ... Sensor (detection means), 71 ... First atmospheric release valve, 73 ... Second atmospheric release valve, 75 ... Drive shaft (axis), DESCRIPTION OF SYMBOLS 7 ... Pressure roller (pressing member), 79 ... Ink chamber (internal space), 80 ... Gas chamber (internal space), 81 ... Press motor (drive means), 82 ... Control part (control means), A ... Non-clamping area (Non-blocking section), B ... clamping area (blocking section), Pb ... branching point, PH ... transformation position (second position), PT ... pressure regulation position (first position).

Claims (9)

At least one first opening that can suck and discharge fluid, at least one second opening that opens the internal space to the atmosphere, and an elastic portion that has elasticity are different in the length direction. A tube in position;
A pump frame having an arcuate cross-sectional support surface capable of supporting the elastic part of the tube along its length direction;
Centering on an axis that is the center of the arc of the support surface between a closed section that crushes the elastic portion and closes the inner space of the tube between the support surface and a non-closed section that is different from the closed section As a circularly movable pressing member,
An atmosphere release valve capable of closing the second opening,
The pressing member is capable of circular motion in either one of a direction approaching the first opening and a direction away from the first opening in the length direction of the tube, and the pressing member is A tube pump characterized in that after moving circularly in the one direction and moving in the closed section, it further circularly moves in the one direction and moves to the non-closed section. 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.
The non-blocking section is a section where the pressing member is with respect to the notch,
The tube pump according to claim 1, wherein the closing section is a section that closes an internal space of the tube by the pressing member pressing the tube against the support surface. The tube pump according to claim 1 or 2, further comprising control means for controlling movement of the atmosphere release valve and the pressing member. The second openings are respectively formed at both side positions of the elastic portion in the length direction of the tube.
4. The tube pump according to claim 3, wherein a plurality of the air release valves are provided for each of the second openings so as to close the openings. 5. An on-off valve capable of closing the first opening;
The tube pump according to claim 3 or 4, wherein the control means changes a valve opening time of the on-off valve in accordance with an amount of fluid discharged from the first opening. A detecting means for detecting the presence or absence of liquid in the internal space of the tube between the first opening and the second opening;
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 1st opening part, and the said detection means detects the said liquid. Tube pump as described in. The tube pump according to claim 6, wherein the volume of the internal space between the detection means and the on-off valve is larger than the volume of the internal space of the elastic portion that can be pressed by the pressing member. . The tube further includes a plurality of branch portions that branch at a branch point between the detection means and the elastic portion in the length direction thereof and communicate with the internal space.
8. The tube pump according to claim 6, wherein the first opening, the on-off valve, and the detection unit are provided for each of the branch portions. 9. 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 first opening 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 8.

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