JP2016087858A - Liquid injection device and maintenance method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid injection device capable of suppressing clogging of a flow passage causing a closed space including openings of nozzles of a liquid injection section to communicate with the atmosphere at the time of idle suction even when suction cleaning is repeatedly performed, and further to provide a maintenance method of the liquid injection device.SOLUTION: A liquid injection device comprises: a liquid injection section 22 having nozzles 21 injecting liquid; a cap 31 forming a closed space SC including openings of the nozzles 21; a suction section 32 suctioning fluid from the closed space SC; a suction flow passage 33 causing the closed space SC and the suction section 32 to communicate with each other and a connection flow passage 34( first connection flow passage 341 and second connection flow passage 342); and a switching section 40 provided in the connection flow passage 34. The switching section 40 switches between a communication state causing the first connection flow passage 341 to communicate with the atmosphere and a non-communication state causing the first connection flow passage 341 to communicate with the second connection flow passage 342 without causing it to communicate with the atmosphere.SELECTED DRAWING: Figure 5

Description

  The present invention relates to a liquid ejecting apparatus such as an ink jet printer and a maintenance method for the apparatus.

  2. Description of the Related Art Conventionally, as an example of a liquid ejecting apparatus, an ink jet printer that performs printing by ejecting ink as an example of a liquid onto a medium such as a sheet from a nozzle formed in a liquid ejecting unit is known. Some printers include a maintenance device that performs suction cleaning to discharge ink regardless of printing from nozzles formed in a liquid ejecting unit in order to maintain good ink ejection characteristics (for example, patents). Reference 1).

  Specifically, such a maintenance device includes a cap that forms a closed space including an opening of a nozzle of a liquid ejecting unit, a suction unit that sucks fluid from the closed space, an air release channel that is connected to the cap, and an air release flow. And an air release valve provided in the road.

  Then, the maintenance device includes ink or bubbles thickened from the nozzle of the liquid ejecting unit by performing the main suction for sucking the fluid from the closed space to the suction unit with the air release valve opened in the suction cleaning. Let the ink drain. Subsequently, the maintenance device discharges the ink accumulated in the closed space, the suction flow path, and the air release flow path by performing idle suction for sucking fluid from the closed space to the suction portion with the air release valve opened. Let

JP 2014-136372 A

  By the way, in the maintenance apparatus as described above, if suction cleaning is performed, ink that could not be discharged after empty suction may remain in the air release channel. Then, the ink remaining in the air release channel thickens or solidifies with time.

  For this reason, if suction cleaning is repeatedly performed, the ink that has been thickened or solidified in the air release channel gradually increases (accumulates), and clogging occurs in the air release channel. There is a risk that it will not be possible.

  In addition, not only the above-described ink jet printer but also a liquid ejecting apparatus that performs suction cleaning of a liquid ejecting unit that ejects a liquid, the situation is generally common.

  The present invention has been made in view of the above problems. The purpose of the liquid ejecting apparatus and the liquid that can suppress clogging of the flow path that communicates the closed space including the nozzle opening of the liquid ejecting unit to the atmosphere at the time of empty suction even when the suction cleaning is repeatedly performed. It is in providing the maintenance method of an injection device.

  A liquid ejecting apparatus that solves the above problems includes a liquid ejecting unit that includes a nozzle that ejects liquid onto a medium, a cap that forms a closed space including an opening of the nozzle, and a suction unit that sucks fluid from the closed space. And a suction channel that communicates the closed space and the suction unit, a connection channel that communicates the closed space and the suction unit, and a switching unit provided in the middle of the connection channel. Of the connection flow paths, a flow path portion between the closed space and the switching portion is defined as a first connection flow path, and a flow path portion between the switching portion and the suction portion is defined as a second flow path. When the connection flow path is used, the switching unit communicates the first connection flow path with the atmosphere and the second connection flow path without communicating the first connection flow path with the atmosphere. Switch between non-communication state to communicate.

  According to the above configuration, when performing suction cleaning, the closed space including the opening of the nozzle of the liquid ejecting unit is formed by the cap, and the main suction for driving the suction unit is performed with the switching unit in a non-communication state. Then, the fluid is sucked from the closed space through the suction channel and the connection channel (the first connection channel and the second connection channel), so that the liquid is discharged from the nozzle of the liquid ejecting unit. That is, the liquid discharged from the nozzle flows through the suction flow path and the connection flow path (the first connection flow path and the second connection flow path).

  Then, in order to exclude the liquid accumulated in the closed space or the like, idle suction is performed in which the suction unit is driven with the switching unit in a communication state. Then, the liquid accumulated in the first connection channel, the closed space, and the suction channel is sucked into the suction unit together with the air that sequentially flows through the first connection channel, the closed space, and the suction channel communicated with the atmosphere. Is done.

  Thus, in the above configuration, the first connection flow path functions as a flow path for sucking fluid from the closed space in the same manner as the suction flow path when the liquid is discharged from the nozzle of the liquid ejecting section (in the main suction). On the other hand, when the closed space is opened to the atmosphere (at the time of empty suction), it functions as an air release channel that allows air to flow from the atmosphere into the closed space. Therefore, even if liquid remains in the first connection channel after the empty suction of the current suction cleaning, the liquid discharged from the nozzles flows through the first connection channel during the main suction of the next suction cleaning. Therefore, it becomes difficult for the liquid to thicken or solidify in the first connection flow path. Therefore, even when the suction cleaning is repeatedly performed, clogging of the flow path (first connection flow path) that communicates the closed space with the atmosphere can be suppressed.

  In the liquid ejecting apparatus, the switching unit includes a valve chamber, a first communication hole that communicates the valve chamber and the first connection flow path, and the valve chamber and the second connection flow path. A state in which the second communication hole that communicates with each other, an air communication hole that communicates the valve chamber and the atmosphere, and a housing that is rotatably accommodated in the valve chamber and closes the air communication hole And a valve that rotates between a first position for communicating the first communication hole and the second communication hole and a second position for communicating the first communication hole and the atmospheric communication hole. It is desirable to have a body.

  According to the above configuration, when the valve body is rotated to the first position, the first communication hole communicating with the first connection flow path and the second connection flow path in a state where the air communication hole is closed. A second communication hole communicating with the second communication hole communicates with the valve chamber. That is, the first connection channel is not communicated with the second connection channel without communicating with the atmosphere.

  On the other hand, when the valve body is rotated to the second position, the first communication hole communicating with the first connection flow path and the air communication hole communicating with the atmosphere are communicated in the valve chamber. That is, it is set as the communication state which makes the 1st connection flow path connect with air | atmosphere. For this reason, the non-communication state and the communication state can be switched by an easy operation of rotating the valve body.

  In the liquid ejecting apparatus, when the valve body is disposed at the first position, the first internal flow path that communicates the first communication hole and the second communication hole; and When arranged at the second position, it is desirable to form a second internal flow path for communicating the first communication hole and the air communication hole.

  According to the above configuration, the first internal flow path and the second internal flow path formed in the valve body, and the first communication hole, the second communication hole, and the air communication hole formed in the housing portion. By switching the connection mode, it is possible to switch between a non-communication state and a communication state. In addition, since the first internal flow path and the second internal flow path are formed in the valve body, the flow path corresponding to these is formed on the valve chamber (accommodating portion) side as compared to the flow path. The degree of freedom of formation tends to be high.

In the liquid ejecting apparatus, it is preferable that the second internal flow path is included in the first internal flow path.
According to the above configuration, in the communication state (at the time of idle suction), the first connection flow path and the atmosphere are communicated via the second internal flow path, while in the non-communication state (at the time of main suction). The first connection flow path and the second connection flow path are communicated with each other through the first internal flow path including the second internal flow path. For this reason, the second internal channel functioning as an air release channel at the time of empty suction is the same as that of the second point in that the liquid discharged from the nozzle of the liquid ejecting unit flows during the main suction of the next suction cleaning. It becomes difficult for the liquid to thicken or solidify in the internal flow path. Therefore, clogging in the second internal channel can be suppressed.

In the liquid ejecting apparatus, the first internal flow path may communicate the first communication hole and the second communication hole even when the valve body is disposed at the second position. desirable.
According to the above configuration, in the state where the valve body is disposed at the second position, that is, in the communication state, the first communication hole, the second communication hole, and the atmosphere communication hole are all communicated with each other. The connection channel, the second connection channel, and the atmosphere are all in communication.

  For this reason, during idle suction, air flows not only through the first connection flow path but also through the second connection flow path. Therefore, even if liquid may remain in the second connection flow path during the main suction, the liquid remaining in the second connection flow path during the empty suction will be retained in the atmosphere communication hole and the first internal flow. The air is sucked into the suction section together with the air flowing in order through the path, the second communication hole, and the second connection flow path. That is, according to the above configuration, it is possible to prevent the liquid from remaining in the second connection channel after the suction cleaning is performed.

In the liquid ejecting apparatus, it is preferable that the suction unit is provided in common with respect to the suction channel and the connection channel.
According to the above configuration, the liquid ejecting unit can be suction cleaned with a simple configuration because there is no need to provide a plurality of suction units.

In the liquid ejecting apparatus, it is preferable that the suction unit is provided separately for the suction channel and the connection channel.
According to the said structure, a difference can be provided in the suction mode of the fluid in a suction flow path and a connection flow path by controlling the drive of a suction part separately. For this reason, for example, at the time of the main suction, the flow rate of the connection channel is made larger than the flow rate of the suction channel, that is, the liquid discharged from the nozzle flows in the connection channel more than the suction channel. The occurrence of clogging in the first connection channel can be further suppressed. In addition, since individual suction is possible with respect to the suction flow path and the connection flow path at the time of idle suction, it is possible to discharge the liquid more reliably in both flow paths.

In the liquid ejecting apparatus, it is preferable that the switching unit switches to the non-communication state when the liquid is ejected from the nozzle of the liquid ejecting unit to the medium.
According to the above configuration, when the liquid is ejected from the nozzle of the liquid ejecting unit to the medium, the first connection channel does not communicate with the atmosphere, so the liquid remains in the first connection channel. However, the liquid (the solvent component of the liquid) can be made difficult to evaporate.

  A maintenance method for a liquid ejecting apparatus that solves the above problem is a maintenance method for a liquid ejecting apparatus that includes a liquid ejecting unit having a nozzle that ejects a liquid onto a medium, and forms a closed space including an opening of the nozzle. A closed space forming step, a first suction step for sucking fluid from the closed space via a suction channel and a connection channel, and an atmosphere release step for communicating the closed space to the atmosphere via the connection channel; And a second suction step of sucking fluid from the closed space through the suction flow path in a state where the closed space is communicated with the atmosphere.

  According to the configuration described above, it is possible to obtain the operational effects achieved by the liquid ejecting apparatus described above.

FIG. 3 is a perspective view illustrating a schematic configuration of the liquid ejecting apparatus according to the first embodiment. The schematic diagram of the maintenance apparatus of 1st Embodiment. Sectional drawing which shows the switching part of 1st Embodiment typically. (A), (b) is a schematic diagram which shows the state of the maintenance apparatus at the time of this suction. (A), (b) is a schematic diagram which shows the state of the maintenance apparatus at the time of idle suction. Sectional drawing which shows typically a switching part when a valve body is arrange | positioned in another 2nd position. The schematic diagram of the maintenance apparatus of a modification. (A), (b) is sectional drawing which shows typically the switch part of a 1st modification. (A), (b) is sectional drawing which shows typically the switch part of a 2nd modification. (A), (b) is sectional drawing which shows typically the switching part of the 3rd modification. (A), (b) is sectional drawing which shows typically the switching part of the 4th modification. (A), (b) is sectional drawing which shows typically the switch part of the 5th modification.

Hereinafter, an embodiment in which a liquid ejecting apparatus is embodied in an ink jet printer (hereinafter also simply referred to as “printer”) will be described with reference to the drawings.
As shown in FIG. 1, the liquid ejecting apparatus 11 includes a main body case 12 having a substantially rectangular box shape. A support base 13 extends along the scanning direction X, which is the longitudinal direction, of the lower portion of the main body case 12. On the support base 13, the medium M is transported in the transport direction Y by a paper feed mechanism (not shown) based on driving of a transport motor 14 provided at the lower back of the main body case 12.

  A guide shaft 15 is laid along the scanning direction X above the support base 13 in the main body case 12. A carriage 16 is supported on the guide shaft 15 so as to be capable of reciprocating in the scanning direction X.

  A driving pulley 17a and a driven pulley 17b are rotatably supported at positions corresponding to both ends of the guide shaft 15 on the inner surface of the rear wall of the main body case 12. A carriage motor 18 serving as a drive source for reciprocating the carriage 16 is connected to the drive pulley 17a.

  An endless timing belt 19, which is partially connected to the carriage 16, is wound between the driving pulley 17 a and the driven pulley 17 b. Therefore, the carriage 16 is moved in the scanning direction X via the endless timing belt 19 while being guided by the guide shaft 15 by driving the carriage motor 18.

  A liquid ejecting section 22 in which a nozzle 21 (see FIG. 2) for ejecting liquid is formed is provided below the carriage 16. Further, a liquid storage portion 23 for supplying liquid to the liquid ejecting portion 22 is detachably attached vertically above the carriage 16. Then, the liquid is ejected from the nozzle 21 of the liquid ejecting section 22 that reciprocates in the scanning direction X onto the medium M that is intermittently transported in the transport direction Y. That is, in a printer as an example of a liquid ejecting apparatus, characters, images, and the like are printed on the medium M by ejecting ink as an example of a liquid.

  At the home position (on the lower right side in FIG. 1) in the scanning direction X with respect to the support base 13 in the main body case 12, a maintenance device 30 for performing maintenance such as suction cleaning on the liquid ejecting unit 22 is provided. Yes. During the maintenance of the liquid ejecting unit 22, the carriage 16 is moved to the home position.

Next, the maintenance device 30 will be described with reference to FIG.
As shown in FIG. 2, the maintenance device 30 includes a cap 31 that forms a closed space SC (see FIG. 4) including an opening of the nozzle 21, a suction unit 32 that sucks fluid from the closed space SC, and a closed space SC. A suction channel 33 and a connection channel 34 that communicate with the suction unit 32, and an atmosphere communication channel 35 that allows the connection channel 34 to communicate with the atmosphere.

  In addition, the maintenance device 30 is provided in the middle of the connection flow path 34, and the switching unit 40 that switches the connection state between the connection flow path 34 and the atmosphere communication path 35 (atmosphere), and the suction part 32 are sucked from the closed space SC. A waste liquid storage unit 36 that stores a liquid contained in the fluid (hereinafter also referred to as “waste liquid”), and a waste liquid channel 37 that communicates the suction unit 32 and the waste liquid storage unit 36.

  In the following description, a portion of the connection channel 34 between the cap 31 (closed space SC) and the switching unit 40 is referred to as a “first connection channel 341”, and the switching unit 40 and the suction channel are suctioned. A channel portion between the portion 32 and the portion 32 is referred to as a “second connection channel 342”.

  As shown in FIG. 2, the cap 31 has a bottomed box shape, and a plurality of communication holes 38 and 39 (two in the present embodiment) communicating with the inside and the outside of the cap 31 are formed through the bottom wall. . The suction channel 33 is connected to one communication hole 38, and the connection channel 34 (first connection channel 341) is connected to the other communication hole 39. In addition, the cap 31 moves between a “contact position” that forms a closed space SC by contacting the liquid ejecting unit 22 disposed at the home position, and a “retracted position” that is retracted from the liquid ejecting unit 22.

  A suction channel 33 and a connection channel 34 (second connection channel 342) are connected to the suction part 32. For this reason, when the suction part 32 is driven, fluid is sucked through the suction flow path 33 and the connection flow path 34. In this regard, in the present embodiment, the suction part 32 is provided in common for the suction flow path 33 and the connection flow path 34. The fluid sucked by the suction unit 32 includes liquid and air discharged from the nozzle 21 of the liquid ejecting unit 22. For this reason, as for the suction part 32, it is desirable that it is a suction pump which can attract | suck the fluid with which the liquid and gas were mixed.

  The suction flow path 33, the connection flow path 34, the atmosphere communication path 35, and the waste liquid flow path 37 are flow paths formed in a liquid supply tube such as rubber. The suction flow path 33, the connection flow path 34, the atmosphere communication path 35, and the waste liquid flow path 37 may be flow paths formed by a combination of resin flow path forming members.

Next, the switching unit 40 will be described with reference to FIG.
As shown in FIG. 3, the switching unit 40 includes a valve body 50 and a storage unit 60 having a valve chamber VC that rotatably stores the valve body 50. Here, the shapes of the valve body 50 and the valve chamber VC may be any shape as long as the valve body 50 can rotate while sliding on the wall surface of the valve chamber VC. For example, the valve body 50 may have a cylindrical shape or a spherical shape. Alternatively, an ellipsoidal shape may be used. That is, FIG. 3 illustrates a cross section that intersects (orthogonally) the rotational axis direction of the valve body 50 with respect to the accommodating portion 60 having the valve body 50 and the valve chamber VC.

  The valve body 50 is formed of a material such as elastically deformable rubber. In addition, the valve body 50 is provided with a first through flow path 51 and a second through flow path 52 that penetrate the valve body 50. The first through channel 51 and the second through channel 52 are orthogonal to each other on the outer peripheral surface of the valve body 50. For this reason, one flow path opening of the first through flow path 51 and the second through flow path 52 opens at the same position on the outer peripheral surface of the valve body 50, and the first through flow path 51 and the second through flow path The other flow passage opening of the through flow passage 52 is opened at a position facing the outer peripheral surface of the valve body 50.

  The accommodating portion 60 has a first communication hole 61 that communicates the valve chamber VC and the first connection flow path 341, and a second communication hole 62 that communicates the valve chamber VC and the second connection flow path 342. And an air communication hole 63 communicating the valve chamber VC and the air communication path 35 (atmosphere). In the accommodating part 60, the 1st communicating hole 61 and the 2nd communicating hole 62 are arrange | positioned so that it may oppose. Further, in the housing portion 60, the formation direction of the atmospheric communication hole 63 is orthogonal to the formation direction of the first communication hole 61 and the second communication hole 62.

  On the opposite side of the first communication hole 61, the second communication hole 62, and the atmosphere communication hole 63 from the valve chamber VC side, enlarged diameter portions 64, 65, 66 in which the diameters of the respective holes are enlarged are provided. ing. A first connection flow path 341 is connected to the enlarged diameter portion 64 of the first communication hole 61, and a second connection flow path 342 is connected to the enlarged diameter portion 65 of the second communication hole 62, so that air communication is possible. An air communication path 35 is connected to the enlarged diameter portion 66 of the hole 63.

  In the switching unit 40, the valve body 50 rotates, so that the first communication hole 61, the second communication hole 62, the atmosphere communication hole 63 of the housing unit 60, and the first through flow of the valve body 50. The connection mode with the channel 51 and the second through channel 52 is switched. Further, in the switching unit 40, the valve body 50 rotates, so that the blocking mode of the first communication hole 61, the second communication hole 62, and the atmosphere communication hole 63 of the housing unit 60 by the valve body 50 is switched.

  Next, the operation of the maintenance device 30 of the liquid ejecting apparatus 11 will be described with reference to FIGS. 4 and 5, the flow of fluid (mainly liquid) at the time of main suction is indicated by solid arrows, and the flow of fluid (mainly air) at the time of idle suction is indicated by broken arrows. Note that the meanings of the solid line arrow and the broken line arrow are the same in FIG.

  As shown in FIG. 4A, when the maintenance device 30 performs suction cleaning, after moving the carriage 16 to the home position, the cap 31 is moved to the contact position to open the nozzle 21 opening. A closed space SC is formed (closed space forming step). Subsequently, the state of the switching unit 40 is switched in order to discharge the liquid from the nozzle 21 of the liquid ejecting unit 22.

  That is, as shown in FIG. 4B, the first communication hole 61 in a state where the valve body 50 closes the atmosphere communication hole 63 of the storage unit 60 by rotating the valve body 50 of the switching unit 40. And the first through channel 51 are communicated with each other, and the second communication hole 62 and the second through channel 52 are communicated with each other. Then, the first connection channel 341 is switched to the “non-communication state” in which the first connection channel 341 is communicated with the second connection channel 342 without communicating with the atmosphere communication channel 35 (atmosphere).

Here, in the non-communication state, the first communication hole 61 and the second communication hole 62 of the housing portion 60 communicate with each other by the first through flow path 51 and the second through flow path 52 of the valve body 50. Is done.
In this respect, the arrangement of the valve body 50 shown in FIGS. 4A and 4B corresponds to the “first position”, and the first through flow channel 51 and the second through flow channel 52 are “first”. Corresponds to “internal flow path”.

  Subsequently, when switching to the non-communication state, the suction unit 32 is driven, and the main suction for sucking the fluid from the closed space SC is performed via the suction channel 33 and the connection channel 34 (first suction step). . When the main suction is performed, the inside of the closed space SC is gradually depressurized, and the inside of the closed space SC becomes a negative pressure, whereby the liquid is discharged from the nozzle 21 of the liquid ejecting unit 22. That is, the liquid including the bubbles or the thickened liquid is discharged inside the liquid ejecting unit 22 or the nozzle 21, thereby recovering the liquid ejection failure in the nozzle 21.

  At the time of the main suction, the flow path through which the liquid flows is the suction flow path 33, the connection flow path 34 (the first connection flow path 341 and the second connection flow path 342), and the first flow path in the switching unit 40. These are the through channel 51, the second through channel 52, and the waste liquid channel 37. In other words, when the main suction is finished, not only the liquid remains in the closed space SC as shown in FIG. 4A, but also the liquid may remain in these flow paths.

  When the main suction is completed, the first connection flow path 341 communicating with the closed space SC is communicated with the atmosphere in order to remove the liquid remaining in the closed space SC and the like (atmospheric release step). In addition, what is necessary is just to judge the timing which complete | finishes this attraction | suction by the elapsed time after starting the suction part 32, for example.

  That is, as shown in FIGS. 5A and 5B, the first communicating hole 61 and the atmospheric communicating hole 63 are connected to the second communicating body 61 by rotating the valve body 50 of the switching unit 40 half a turn (180 degrees). The second communication hole 62 and the atmosphere communication hole 63 are communicated with each other through the first through flow channel 51 while being communicated with each other through the through flow channel 52.

  Then, as shown in FIG. 5B, the first connection flow path 341 and the atmosphere communication path 35 (atmosphere) are switched to the “communication state”. In the present embodiment, the second connection flow path 342 and the atmosphere communication path 35 are also communicated in the communication state.

  Here, in the communication state, the first communication hole 61 of the housing portion 60 and the atmosphere communication hole 63 are communicated with each other by the second through passage 52 of the valve body 50. In this regard, the arrangement of the valve body 50 shown in FIGS. 5A and 5B corresponds to the “second position”, and the second through flow path 52 corresponds to the “second internal flow path”. .

  Further, in the communication state, that is, when the valve body 50 is disposed at the second position, the first communication hole of the housing portion 60 is formed by the first through flow channel 51 and the second through flow channel 52. 61 and the 2nd communicating hole 62 are connected. In this regard, even when the valve body 50 is disposed at the second position, the first through flow path 51 and the second through flow path 52 correspond to the “first internal flow path”.

  Further, in the present embodiment, the second through flow path 52 corresponds to the second internal flow path, while the first through flow path 51 and the second through flow path 52 correspond to the first internal flow path. Thus, it can be said that the second internal flow path is included in the first internal flow path.

  Subsequently, when the communication state is switched, the closed space SC is communicated with the atmosphere via the first connection flow path 341, so that the negative pressure in the closed space SC is eliminated. Incidentally, when switching to the communication state, the driving of the suction unit 32 may be temporarily stopped, or the driving of the suction unit 32 may be continued. Then, in order to exclude liquid accumulated in the closed space SC or the like, idle suction for sucking fluid from the closed space SC is performed in a state where the closed space SC is in communication with the atmosphere (second suction step).

  When the main suction is performed, as shown in FIGS. 5A and 5B, the first connection channel 341 communicates with the atmosphere, so the first connection channel via the atmosphere communication path 35. Air flows into 341. As a result, the liquid remaining in the first connection channel 341, the closed space SC, and the suction channel 33 is removed from the atmosphere communication channel 35, the atmosphere communication hole 63, the second through channel 52, the first communication hole 61, The air is sucked into the suction portion 32 together with the air flowing through the first connection flow path 341, the closed space SC, and the suction flow path 33 in order.

  In the present embodiment, since the second connection channel 342 is also communicated with the atmosphere, air also flows into the second connection channel 342 via the atmosphere communication channel 35. As a result, the liquid remaining in the second connection channel 342 passes through the atmosphere communication path 35, the atmosphere communication hole 63, the first through channel 51, the second communication hole 62, and the second connection channel 342 in order. The air is sucked into the suction part 32 together with the circulating air. Then, the liquid sucked into the suction part 32 flows through the waste liquid channel 37 and is stored in the waste liquid storage part 36.

  Thus, the first connection flow path 341 and the second connection flow path 342 function as a flow path for sucking fluid from the closed space SC in the same way as the suction flow path 33 during the main suction, In this case, it functions as a flow path for flowing air from the atmosphere into the closed space SC.

  For this reason, even if liquid may remain in the first connection channel 341 and the second connection channel 342 after idle suction, the first connection channel 341 and the second connection channel 341 at the time of the main suction of the next suction cleaning. The liquid discharged from the nozzle 21 circulates in the first connection flow path 342, so that it is difficult for the liquid to thicken or solidify in the first connection flow path 341 and the second connection flow path 342. Therefore, even when the suction cleaning is repeatedly performed, clogging of the flow paths (the first connection flow path 341 and the second connection flow path 342) that communicate the closed space SC with the atmosphere is suppressed.

  The same can be said for the flow path formed inside the switching unit 40. In other words, the first through flow path 51 and the second through flow path 52 (first internal flow path and second internal flow path) through which air flows during empty suction are discharged from the nozzle 21 during the main suction. It becomes a flow path through which liquid flows. Therefore, even if liquid may remain in the first through flow path 51 and the second through flow path 52 after the empty suction of the current suction cleaning, the first through flow path at the time of the main suction of the next suction cleaning. The liquid discharged from the nozzle 21 flows through 51 and the second through-flow channel 52, so that the liquid does not easily thicken or solidify in the first through-flow channel 51 and the second through-flow channel 52. Become.

  When the idle suction is completed, the cap 31 moves to the retracted position, and the carriage 16 moves from the home position to a printing area that can face the support base 13 so that liquid can be ejected from the liquid ejecting unit 22 onto the medium. Become. Here, when the liquid ejecting unit 22 ejects the liquid onto the medium, the switching unit 40 switches to the non-communication state. Then, since the first connection flow path 341 and the second connection flow path 342 are not in communication with the atmosphere, it is assumed that liquid remains in the first connection flow path 341 and the second connection flow path 342. However, the evaporation of the liquid (the solvent component of the liquid) is suppressed.

  When the liquid ejecting unit 22 does not eject liquid to the medium, such as when the liquid ejecting apparatus 11 is not used, the liquid ejecting unit 22 is moved to the home position and the cap 31 is moved to the contact position. The state of the connection channel 34 may be switched to a non-communication state. Then, the communication holes 38 and 39 formed in the bottom wall of the cap 31 do not communicate with the atmosphere via the opening of the cap 31, so that the first connection channel 341 and the second connection channel 342 described above The liquid evaporation is further suppressed.

According to the first embodiment described above, the following effects can be obtained.
(1) When the switching unit 40 switches between the non-communication state and the communication state, the first connection channel 341 is closed when the liquid is discharged from the nozzle 21 of the liquid ejecting unit 22 (at the time of main suction). Functions as a flow path for injecting air from the atmosphere to the closed space SC when the closed space SC is opened to the atmosphere (at the time of empty suction). Therefore, even if liquid remains in the first connection flow path 341 after the empty suction of the current suction cleaning, the liquid was discharged from the nozzle 21 to the first connection flow path 341 during the main suction of the next suction cleaning. Since the liquid circulates, it becomes difficult for the liquid to thicken or solidify in the first connection channel 341. Therefore, even when the suction cleaning is repeatedly performed, clogging of the flow path (first connection flow path 341) that communicates the closed space SC with the atmosphere can be suppressed.

  (2) While the valve body 50 is rotated to the first position, the non-communication state is achieved, and the valve body 50 is rotated to the second position, so that the communication state can be achieved. That is, the non-communication state and the communication state can be switched by an easy operation of rotating the valve body 50.

  (3) The first through channel 51 and the second through channel 52 (the first internal channel and the second internal channel) formed in the valve body 50 and the first through channel formed in the accommodating portion 60. By switching the connection mode between the first communication hole 61, the second communication hole 62, and the atmospheric communication hole 63, the non-communication state and the communication state can be switched. For this reason, compared with the case where the flow path corresponded to these is formed in the valve chamber VC (accommodating part 60) side, the formation freedom degree of a flow path can be made high.

  (4) In the communication state, the first connection channel 341 communicates with the atmosphere via the second through channel 52 (second internal channel), while in the non-communication state, the first The first connection channel 341 and the second connection channel 342 are communicated with each other through one through channel 51 and the second through channel 52 (first internal channel). For this reason, the second through-flow channel 52 functioning as a channel through which air flows into the closed space SC at the time of empty suction of the current suction cleaning is provided in the liquid discharged from the nozzle 21 at the time of the main suction of the next suction cleaning. In the second through-flow channel 52, it becomes difficult for the liquid to thicken or solidify. Therefore, clogging in the second through channel 52 can be suppressed.

  (5) Since the first connection flow path 341, the second connection flow path 342, and the atmosphere are all communicated in the communication state, not only the first connection flow path 341 but also the first connection flow path 341 The air also flows into the second connection channel 342. Therefore, even if liquid remains in the second connection channel 342 at the time of the main suction, the liquid remaining in the second connection channel 342 at the time of the idle suction is transferred to the atmosphere communication path 35 and the switching unit. 40 and the second connection flow path 342 are sucked into the suction portion 32 together with the air flowing in order. That is, it is possible to suppress the liquid from remaining in the second connection channel 342 after the suction cleaning is performed.

  (6) Since the suction flow path 33 and the connection flow path 34 are connected to the common suction section 32, it is not necessary to provide a plurality of suction sections 32, and suction cleaning of the liquid ejecting section 22 is performed with a simple configuration. Can do.

  (7) When the liquid is ejected from the nozzle 21 of the liquid ejecting unit 22 toward the medium, the first connection channel 341 does not communicate with the atmosphere, so that the liquid remains in the first connection channel 341. Even if it has, it can suppress that the liquid (solvent component of the same liquid) evaporates.

In addition, you may change the said embodiment as shown below.
As shown in FIG. 6, the first communication hole 61 and the atmospheric communication hole 63 are communicated with each other through the first through passage 51, and the second communication hole 62 is closed with the valve body 50. One communication channel 341 and the atmosphere communication path 35 may be in a “communication state”.

  Here, in the communication state, the first through-hole 61 of the housing portion 60 and the atmospheric communication hole 63 communicate with each other through the first through flow path 51 of the valve body 50. In this regard, the arrangement of the valve body 50 shown in FIG. 6 corresponds to a “second position”, and the first through flow path 51 corresponds to a “second internal flow path”.

And even if it is a case where idle suction is performed in the communicating state shown in Drawing 6, effects (1)-(4) of the above-mentioned embodiment can be acquired.
-As shown in FIG. 7, you may provide the suction part 32 with respect to the suction flow path 33 and the connection flow path 34 separately. In other words, the first suction part 321 may be provided in the suction flow path 33 and the second suction part 322 may be provided in the second connection flow path 342.

  According to this, the drive of the 1st suction part 321 and the 2nd suction part 322 can be controlled individually. For example, at the time of the main suction, the flow rate of the connection channel 34 is made larger than the flow rate of the suction channel 33, that is, the liquid discharged from the nozzle 21 flows more through the connection channel 34 than the suction channel 33. In this way, it is possible to further suppress the occurrence of clogging in the first connection channel 341 where the liquid tends to thicken or solidify.

  Further, at the time of idle suction, the first suction channel 321 has a short channel length with respect to the first connection channel 341, the closed space SC, and the suction channel 33 that have a long channel length and in which liquid tends to remain. Since the second connection channel 342 can be sucked by the second suction part 322, the liquid can be discharged more reliably in either channel. Note that the long flow path length means that the flow path length from the atmosphere communication path 35 to the first suction part 321 via the first connection flow path 341 is long, and that the flow path length is short. This means that the flow path length from the atmosphere communication path 35 to the second suction part 322 via the second connection flow path 342 is short.

  In addition, as shown in FIG. 5, when idle suction is performed in a communication state in which the first connection channel 341, the second connection channel 342, and the atmosphere communication channel 35 are communicated, switching from the atmosphere communication channel 35 is performed. Even if the first suction part 321 is driven stronger than the second suction part 322 so that the air flowing into the part 40 flows more in the first connection flow path 341 than in the second connection flow path 342. Good.

  -As shown to Fig.8 (a), (b), in the valve body 501 with which the switching part 401 is provided, the through-flow path 511 which penetrates the valve body 501 to a normal line direction (radial direction), and the through-flow path 511 A branch channel 521 communicating with the through channel 511 may be provided while intersecting (orthogonal) with.

  Then, as shown in FIG. 8A, in the “non-communication state” where the valve body 501 is disposed at the “first position”, the through-flow channel is closed with the air communication hole 63 closed by the valve body 501. The first connection channel 341 and the second connection channel 342 may be communicated with each other by communicating the first communication hole 61 and the second communication hole 62 via 511. That is, in this case, the through channel 511 corresponds to the “first internal channel”.

  On the other hand, as shown in FIG. 8B, in the “communication state” in which the valve body 501 is disposed at the “second position”, the first communication hole is provided via the through flow path 511 and the branch flow path 521. The first connection channel 341, the second connection channel 342, and the atmosphere communication channel 35 may be communicated by communicating the 61, the second communication hole 62, and the atmosphere communication hole 63. That is, in this case, the through flow path 511 corresponds to a “first internal flow path”, and a part of the through flow path 511 and the branch flow path 521 correspond to a “second internal flow path”.

  According to the switching unit 401 shown in FIGS. 8A and 8B, the effects (1) to (3) and (5) of the above embodiment can be obtained. Note that, according to the switching unit 401 shown in FIGS. 8A and 8B, a communication state in which the first connection channel 341 is communicated with the atmosphere communication channel 35 without being connected to the second connection channel 342. You can also

  -As shown to Fig.9 (a), (b), the valve body 502 with which the switching part 402 is provided is provided with the 1st penetration flow path 512 and the 2nd penetration flow path 522 which penetrate the valve body 502. Also good. Here, the first through channel 512 has a channel length corresponding to the distance between the first communication hole 61 and the second communication hole 62, and the second through channel 522 has the first communication channel. The flow path length is set according to the distance between the hole 61 and the air communication hole 63.

  As shown in FIG. 9A, in the “non-communication state” where the valve body 502 is disposed at the “first position”, the first air communication hole 63 is closed with the valve body 502. The first connection channel 341 and the second connection channel 342 may be communicated by communicating the first communication hole 61 and the second communication hole 62 via the through channel 512. That is, in this case, the first through flow path 512 corresponds to the “first internal flow path”.

  On the other hand, as shown in FIG. 9B, in the “communication state” in which the valve body 502 is disposed at the “second position”, the first communication hole 61 and the first communication hole 61 are connected via the second through-flow channel 522. The first connection channel 341 and the atmosphere communication path 35 may be communicated with each other by communicating with the atmosphere communication hole 63. That is, in this case, the second through flow path 522 corresponds to a “second internal flow path”.

  According to the switching unit 402 shown in FIGS. 9A and 9B, the effects (1) to (3) of the above embodiment can be obtained. The first through flow path 512 is a flow path through which fluid (mainly liquid) flows only during the main suction, and the second through flow path 522 is a flow path through which fluid (air) flows only during the empty suction. be able to. That is, the use of the first through channel 512 and the second through channel 522 can be limited.

  As shown in FIGS. 10A and 10B, the valve body 503 provided in the switching unit 403 may have a half-moon shape in a cross-sectional view intersecting (orthogonal) with the rotation axis direction of the valve body 503. . That is, the valve body 503 in this case has a substantially semi-cylindrical shape or a substantially hemispherical shape.

  As shown in FIG. 10A, in the “non-communication state”, the first communication hole 61 and the second communication hole 62 are communicated with the atmospheric communication hole 63 closed by the valve body 503. Thus, the first connection flow path 341 and the second connection flow path 342 may be communicated with each other. On the other hand, as shown in FIG. 10 (b), in the “communication state”, the first communication channel 341 is communicated with the first communication hole 61, the second communication hole 62, and the atmospheric communication hole 63. The second connection flow path 342 and the atmosphere communication path 35 may be communicated with each other.

  According to the switching unit 403 shown in FIGS. 10A and 10B, the effects (1) and (2) of the above embodiment can be obtained. 10A and 10B, the angle of the valve body 503 is adjusted so that the first connection channel 341 is not connected to the second connection channel 342. A communication state in which the air communication path 35 is communicated can also be established.

  As shown in FIGS. 11A and 11B, the accommodating portion 604 provided in the switching portion 404 may form a second communication hole 62 at a position facing the air communication hole 63. In addition, the valve body 504 provided in the switching unit 404 may be provided with a groove 514 that is recessed along the circumferential direction and toward the rotation axis center of the valve body 504. Here, the formation angle of the concave groove 514 in the circumferential direction is approximately 90 degrees.

  11A, in the “non-communication state” in which the valve body 504 is disposed at the “first position”, the groove 514 is closed with the air communication hole 63 closed by the valve body 504. The first connection channel 341 and the second connection channel 342 may be communicated with each other by communicating the first communication hole 61 and the second communication hole 62 via. That is, in this case, the concave groove 514 corresponds to the “first internal flow path”.

  On the other hand, as shown in FIG. 11 (b), in the “communication state” where the valve body 504 is disposed at the “second position”, the first communication hole 61 and the air communication hole 63 are interposed via the concave groove 514. The first connection channel 341 and the atmosphere communication path 35 may be communicated with each other by communicating with each other. That is, in this case, the concave groove 514 corresponds to a “second internal flow path”.

According to the switching unit 404 shown in FIGS. 11A and 11B, the effects (1) to (4) of the above embodiment can be obtained.
As shown in FIGS. 12A and 12B, a first gate valve 71 is provided in the atmosphere communication path 35, and the suction channel 32 side is closer to the portion of the connection flow path 34 communicating with the atmosphere communication path 35. Two gate valves 72 may be provided. Here, the first gate valve 71 and the second gate valve 72 are two-way valves that allow the fluid to flow when the valve is opened while restricting the fluid from flowing when the valve is closed. is there.

  Then, as shown in FIG. 12A, in the “non-communication state”, the first connection valve is opened by closing the first gate valve 71 while opening the second gate valve 72. You may make 341 and the 2nd connection flow path 342 connect. On the other hand, as shown in FIG. 12B, in the “communication state”, the first connection flow path 341 and the second connection are connected by opening the first gate valve 71 and the second gate valve 72. The flow path 342 and the atmosphere communication path 35 may be communicated with each other.

  In this respect, in this case, the switching unit 405 is configured including the first gate valve 71 and the second gate valve 72. And according to the switching part 405 shown to Fig.12 (a), (b), the effect (1) of the said embodiment can be acquired. In addition, according to the switching part 405 shown to Fig.12 (a), (b), the 1st connection flow is made by opening the 1st gate valve 71 and closing the 2nd gate valve 72. A communication state in which the path 341 is communicated with the atmosphere communication path 35 without being connected to the second connection flow path 342 may be employed.

  -Moreover, in the switching part 405 shown to Fig.12 (a), (b), it is not necessary to provide the 2nd gate valve 72. FIG. Also in this way, according to the open / closed state of the first gate valve 71, the connection channel 34 (first connection channel 341) communicates with the atmosphere and the connection channel 34 (first connection channel). 341) can be switched to a non-communication state that does not communicate with the atmosphere.

  The arrangement relationship of the first communication hole 61, the second communication hole 62, and the atmospheric communication hole 63 in the switching unit 40 may be arbitrarily changed. For example, in the cross-sectional view of the switching unit 40 shown in FIG. 3, the first communication hole 61, the second communication hole 62, and the atmospheric communication hole 63 may be formed in a range of 90 degrees in the circumferential direction. In this case, according to the arrangement of the first communication hole 61, the second communication hole 62, and the atmospheric communication hole 63, the formation positions of the first through flow path 51 and the second through flow path 52 with respect to the valve body 50 are determined. It is desirable to change. The same applies to the first to fifth modifications.

A plurality of suction channels 33 may be provided, or a plurality of connection channels 34 may be provided.
The switching unit 40 may switch to the communication state when the liquid is ejected from the nozzle 21 of the liquid ejecting unit 22.

The suction unit 32 may include a pressure chamber that accumulates negative pressure. And when a fluid is sucked from the closed space SC, the fluid may be sucked through the pressure chamber.
As long as the communication state and the non-communication state can be switched, the shape of the valve body 50 and the valve chamber VC may be a rectangular parallelepiped shape.

  The liquid ejecting apparatus 11 may be a line head printer including an elongated fixed liquid ejecting unit 22 corresponding to the entire width of the medium M. In this case, the liquid ejecting unit 22 may be arranged so that the printing range covers the entire width of the medium M by arranging a plurality of unit head units in which the nozzles 21 are formed in parallel, or a single long head. By arranging a large number of nozzles 21 so as to extend over the entire width of the medium M, the printing range may extend over the entire width of the medium M.

  The liquid ejected by the liquid ejecting unit 22 is not limited to ink, and may be, for example, a liquid material in which functional material particles are dispersed or mixed in the liquid. For example, recording is performed by ejecting a liquid material in which a material such as an electrode material or a color material (pixel material) used for manufacturing a liquid crystal display, an EL (electroluminescence) display, and a surface emitting display is dispersed or dissolved. It may be configured.

  The medium M is not limited to paper, and may be a plastic film or a thin plate material, or may be a fabric used in a printing apparatus or the like.

  DESCRIPTION OF SYMBOLS 11 ... Liquid injection apparatus, 21 ... Nozzle, 22 ... Liquid injection part, 30 ... Maintenance apparatus, 31 ... Cap, 32 ... Suction part, 321 ... 1st suction part (an example of a suction part), 322 ... 2nd suction Part (an example of a suction part), 33 ... suction channel, 34 ... connection channel, 341 ... first connection channel, 342 ... second connection channel, 35 ... atmospheric communication channel, 40, 401, 402, 403, 404, 405 ... switching unit, 50, 501, 502, 503, 504 ... valve body, 51, 511, 512 ... first through channel, 514 ... concave groove, 52, 522 ... second through channel 521 ... Branch channel, 60,604 ... accommodating part, 61 ... first communication hole, 62 ... second communication hole, 63 ... atmospheric communication hole, M ... medium, SC ... closed space, VC ... valve chamber.

Claims (9)

A liquid ejecting section having a nozzle for ejecting liquid onto the medium;
A cap that forms a closed space including an opening of the nozzle;
A suction part for sucking fluid from the closed space;
A suction flow path communicating the closed space and the suction portion;
A connection flow path communicating the closed space and the suction portion;
A switching unit provided in the middle of the connection flow path,
Of the connection flow paths, a flow path portion between the closed space and the switching unit is defined as a first connection flow path, and a flow path portion between the switching unit and the suction unit is defined as a second connection flow. When it is a road,
The switching unit includes a communication state in which the first connection channel is communicated with the atmosphere, and a non-communication state in which the first connection channel is communicated with the second connection channel without communicating with the atmosphere. Switching liquid ejector. The switching unit is
A first communication hole having a valve chamber and communicating the valve chamber and the first connection flow path; a second communication hole communicating the valve chamber and the second connection flow path; An accommodating portion in which an air communication hole communicating the valve chamber and the atmosphere is formed;
A first position that is rotatably accommodated in the valve chamber and communicates with the first communication hole and the second communication hole in a state in which the air communication hole is closed, the first communication hole, The liquid ejecting apparatus according to claim 1, further comprising: a valve body that rotates between a second position that communicates with the atmosphere communication hole. In the valve body,
A first internal flow path for communicating the first communication hole and the second communication hole when disposed at the first position;
3. The liquid ejecting apparatus according to claim 2, wherein a second internal flow path that connects the first communication hole and the air communication hole when formed at the second position is formed. The liquid ejecting apparatus according to claim 3, wherein the second internal flow path is included in the first internal flow path. 5. The first internal flow path allows the first communication hole and the second communication hole to communicate with each other even when the valve body is disposed at the second position. The liquid ejecting apparatus according to 1. The liquid ejecting apparatus according to claim 1, wherein the suction unit is provided in common for the suction flow path and the connection flow path. The liquid ejecting apparatus according to claim 1, wherein the suction unit is individually provided for the suction channel and the connection channel. The liquid ejecting apparatus according to claim 1, wherein the switching unit switches to the non-communication state when the liquid is ejected from the nozzle of the liquid ejecting unit to the medium. A maintenance method for a liquid ejecting apparatus including a liquid ejecting unit having a nozzle for ejecting liquid to a medium,
A closed space forming step for forming a closed space including the opening of the nozzle;
A first suction step for sucking fluid from the closed space via a suction channel and a connection channel;
An atmosphere release step for communicating the closed space with the atmosphere via the connection flow path;
A second suction step of sucking fluid from the closed space through the suction flow path in a state where the closed space is in communication with the atmosphere.